Publicaciones

 

MEDICINA Y CIENCIAS MÉDICAS

1).- PROYECTO DISFUNCIÓN MITOCONDRIAL COMO MEDIADOR DE MUERTE CELULAR INDUCIDA POR KETAMINA EN CÉLULAS NEURONALES: EFECTO SOBRE EL METABOLISMO DEL CALCIO MITOCONDRIAL.CAECIHS, SECRETARÍA DE INVESTIGACIÓN (UAI)
Director: Dra Juanita Bustamante mail juanita.bustamante@uai.edu.ar Inicio 2015 y renovación hasta actual.

    A).-Free radical production and antioxidant status in brain cortex non-synaptic mitochondria and synaptosomes at alcohol hangover onset
    Analía G. Karadayian, Gabriela Malanga, Analía Czerniczyniec, Paulina Lombardi, Juanita Bustamante, Silvia Lores-Arnaiz.
    Free Radical Biology and Medicine 108 (2017) 692–703

    Abstract
    Alcohol hangover (AH) is the pathophysiological state after a binge-like drinking. We have previously
    demonstrated that AH induced bioenergetics impairments in a total fresh mitochondrial fraction in brain cortex
    and cerebellum. The aim of this work was to determine free radical production and antioxidant systems in nonsynaptic
    mitochondria and synaptosomes in control and hangover animals. Superoxide production was not
    modified in non-synaptic mitochondria while a 17.5% increase was observed in synaptosomes. A similar
    response was observed for cardiolipin content as no changes were evidenced in non-synaptic mitochondria while
    a 55% decrease in cardiolipin content was found in synaptosomes. Hydrogen peroxide production was 3-fold
    increased in non-synaptic mitochondria and 4-fold increased in synaptosomes. In the presence of deprenyl,
    synaptosomal H2O2 production was 67% decreased in the AH condition. Hydrogen peroxide generation was not
    affected by deprenyl addition in non-synaptic mitochondria from AH mice. MAO activity was 57% increased in
    non-synaptic mitochondria and 3-fold increased in synaptosomes. Catalase activity was 40% and 50% decreased
    in non-synaptic mitochondria and synaptosomes, respectively. Superoxide dismutase was 60% decreased in nonsynaptic mitochondria and 80% increased in synaptosomal fractions. On the other hand, GSH (glutathione)
    content was 43% and 17% decreased in synaptosomes and cytosol. GSH-related enzymes were mostly affected in
    synaptosomes fractions by AH condition. Acetylcholinesterase activity in synaptosomes was 11% increased due
    to AH. The present work reveals that AH provokes an imbalance in the cellular redox homeostasis mainly affecting mitochondria present in synaptic terminals.

    B).- Alcohol hangover: impairments in behavior and bioenergetics in central nervous system
    Analia G. Karadayian, Juanita Bustamante, Silvia Lores-Arnaiz1
    BIOCELL  2016 40(1): 31-34

    Abstract:

    Alcohol hangover (AH) is defined as the temporary state after alcohol binge-like drinking, starting when EtOH is absent in plasma. Results from our laboratory have shown behavioral impairments and mitochon­drial dysfunction in an experimental model of AH in mice. Our model consisted in a single i.p. injection of EtOH (3.8 g/kg BW) or saline solution in male and female mice, sacrificing the animals 6 hours after injection. Motor and affective behavior together with mitochondrial function and free radical production were evaluated in brain cortex and cerebellum during AH. Results showed that hangover animals exhibited a significant reduction in neuromus­c-xular coordination, motor strength and locomotion together with a loss of gait stability and walking deficiencies. Moreover, an increment in anxiety-like behavior together with fear-related phenotype and depression signs were observed. In relation to bioenergetics metabolism, AH induced a reduction in oxygen uptake, inhibition of respira­tory complexes, changes in mitochondrial membrane permeability, decrease in transmembrane potential, increase in O2•- and H2O2 production and impairment in nitric oxide metabolism. All together our data suggest that the phys­iopathological state of AH involves behavioral impairments and mitochondrial dysfunction in mouse brain cortex and cerebellum showing the long lasting effects of acute EtOH exposure in CNS.
    Response to the Letter to the Editor: “Mitochondria isolated from the striatum of the brain exhibit a higher degree of oxidative phosphorylation coupling, which shows that they are not subject to energetic dysfunction upon acute paraquat administration”
    A. Czerniczyniec & AG. Karadayian1 & J. Bustamante & S. Lores-Arnaiz
    J Bioenerg Biomembr (2016) 48:553–555  DOI 10.1007/s10863-016-9680

    C).- Ketamine effect on intracellular and mitochondrial calcium mobilization
    Juanita Bustamente, Analía Czerniczyniec, Silvia  Lorez Arnaiz
    BIOCELL Año: 2016 vol. 40 p. 11 - 11

    Abstract:

    The suppressive effect of ketamine on intracellular calcium has been reported in a variety of cells although the mechanisms involved are not well understood. The aim of this work was to evaluate the effect of ketamine on mitochondrial Ca2+ accumulation and on cellular Ca2+ mobilization using FLUO4-AM and flow cytometry. The results showed that hipoccampal mitochondria from ketamine injected animals presented a lower ability to retain calcium at concentrations higher than 20 mM, as compared with controls (saline injected animals). In addition, ketamine produced a significant decrease in KCl-induced intracellular Ca2+ influx in Vero cell cultures. According to these data, ketamine produces a clear inhibitory effect on cytosolic Ca2+ transport mechanisms, independent of the Ca2+ channel associated NMDA receptor.

    D):_ Brain cortex mitochondrial bioenergetics in synaptosomes and non-synaptic mitochondria during aging.
    Lores-Arnaiz S, Lombardi P, Karadayian AG, Orgambide F, Cicerchia D, Bustamante J.
    Neurochem Res. 2016 Feb;41(1-2):353-63. doi: 10.1007/s11064-015-1817-5. Epub 2016 Jan 28.

    Abstract:

    Alterations in mitochondrial bioenergetics have been associated with brain aging. In order to evaluate the susceptibility of brain cortex synaptosomes and non-synaptic mitochondria to aging-dependent dysfunction, male Swiss mice of 3 or 17 months old were used. Mitochondrial function was evaluated by oxygen consumption, mitochondrial membrane potential and respiratory complexes activity, together with UCP-2 protein expression. Basal respiration and respiration driving proton leak were decreased by 26 and 33 % in synaptosomes from 17-months old mice, but spare respiratory capacity was not modified by aging. Succinate supported state 3 respiratory rate was decreased by 45 % in brain cortex non-synaptic mitochondria from 17-month-old mice, as compared with young animals, but respiratory control was not affected. Synaptosomal mitochondria would be susceptible to undergo calcium-induced depolarization in 17 months-old mice, while non-synaptic mitochondria would not be affected by calcium overload. UCP-2 was significantly up-regulated in both synaptosomal and submitochondrial membranes from 17-months old mice, compared to young animals. UCP-2 upregulation seems to be a possible mechanism by which mitochondria would be resistant to suffer oxidative damage during aging.

    E).- Impairment of striatal mitochondrial function by acute paraquat poisoning.
    Czerniczyniec A1, Lanza EM2, Karadayian AG2, Bustamante J3, Lores-Arnaiz S2.
J Bioenerg Biomembr. 2015 Oct;47(5):395-408. doi: 10.1007/s10863-015-9624-x. Epub 2015 Sep

Abstract:

Mitochondria are essential for survival. Their primary function is to support aerobic respiration and to provide energy for intracellular metabolic pathways. Paraquat is a redox cycling agent capable of generating reactive oxygen species. The aim of the present study was to evaluate changes in cortical and striatal mitochondrial function in an experimental model of acute paraquat toxicity and to compare if the brain areas and the molecular mechanisms involved were similar to those observed after chronic exposure. Sprague-Dawley rats received paraquat (25 mg/Kg i.p.) or saline and were sacrificed after 24 h. Paraquat treatment decreased complex I and IV activity by 37 and 21 % respectively in striatal mitochondria. Paraquat inhibited striatal state 4 and state 3 KCN-sensitive respiration by 80 % and 62 % respectively, indicating a direct effect on respiratory chain. An increase of 2.2 fold in state 4 and 2.3 fold in state 3 in KCN-insensitive respiration was observed in striatal mitochondria from paraquat animals, suggesting that paraquat redox cycling also consumed oxygen. Paraquat treatment increased hydrogen peroxide production (150 %), TBARS production (42 %) and cardiolipin oxidation/depletion (12 %) in striatal mitochondria. Also, changes in mitochondrial polarization was induced after paraquat treatment. However, no changes were observed in any of these parameters in cortical mitochondria from paraquat treated-animals. These results suggest that paraquat treatment induced a clear striatal mitochondrial dysfunction due to both paraquat redox cycling reactions and impairment of the mitochondrial electron transport, causing oxidative damage. As a consequence, mitochondrial dysfunction could probably lead to alterations in cellular bioenergetics.

     

    2).- PROYECTO SOBRE-EXPRESIÓN DE CICLOFILINAS EN EL PARÁSITO UNICELULAR TRYPANOSOMA CRUZI: DESARROLLO DE HERRAMIENTAS PARA EL ANÁLISIS DE LA FUNCIÓN DE PROTEÍNAS.
    Director: Dra Jacquelin Búa email jacbua@yahoo.com Inicio 2007 y renovación hasta actual.

    A).- Mitochondrial permeability transition in protozoan parasites: what we learned from Trypanosoma cruzi

PL Bustos, AE Perrone, NA Milduberger and J Bua
Cell Death and Disease (2017) 8, e3057; doi:10.1038/cddis.2017.431; published online 21 September 2017

Regulated cell death (RCD) involves a genetically encoded molecular machinery, which can be altered by means of pharmacologic and/or genetics interventions targeting the key components of such machinery. RCD often occurs in a delayed manner and is initiated in the context of adaptive responses that unsuccessfully attempt to restore cellular homeostasis. It is important to mention that the term RCD includes both physiological instances of death, referred to as ‘programmed cell death’, but also death processes that occur in pathological contexts. Our comprehension of cell death subroutines has progressed significantly, as the main molecular events underlying these mechanisms have been elucidated.

B).- A homologue of cyclophilin D is expressed in Trypanosoma cruzi and is involved in the oxidative stress-damage response
Patricia L. Bustos, Bibiana J. Volta, Alina E. Perrone, Natalia Milduberger y Jacqueline Bua.
Aceptado 2016

Abstract:
Mitochondria play an important role in energy production, homeostasis and cell death. The opening of the mitochondrial permeability transition pore (mPTP) is considered one of the key events in apoptosis
and necrosis, modulated by cyclophilin D (CyPD), considered a crucial component of this protein complex. In Trypanosoma cruzi, the protozoan parasite that causes Chagas disease, we have previously
described that mitochondrial permeability transition occurs after oxidative stress induction in a cyclosporin A-dependent manner, a well-known cyclophilin inhibitor. In the present work, a mitochondrial parasite cyclophilin, named TcCyP22, which is homologue to the mammalian CyPD was identified. TcCyP22-overexpressing parasites showed an enhanced loss of mitochondrial membrane  potential and loss of cell viability when exposed to a hydrogen peroxide stimulus compared to control  parasites. Our results describe for the first time in a protozoan parasite that this mitocondrial  cyclophilin, homologue to the CyPD involved in the formation of the permeability transition pore, is involved in regulated cell death induced by oxidative stress in T.cruzi

C).- Oxidative stress damage in the protozoan parasite Trypanosoma cruzi is inhibited by Cyclosporin A.
 Bustos PL, Perrone AE, Milduberger N, Postan M, Bua J.
Parasitology. 2015 Jul;142(8):1024-32. doi: 10.1017/S0031182015000232. Epub 2015 Mar 31.

Abstract:
Cyclosporin A (CsA) specifically inhibits the mitochondrial permeability transition pore (mPTP). Opening of the mPTP, which is triggered by high levels of matrix [Ca2+] and/or oxidative stress, leads to mitochondrial dysfunction and thus to cell death by either apoptosis or necrosis. In the present study, we analysed the response of Trypanosoma cruzi epimastigote parasites to oxidative stress with 5 mm H2O2, by studying several features related to programmed cell death and the effects of pre-incubation with 1 μ m of CsA. We evaluated TcPARP cleavage, DNA integrity, cytochrome c translocation, Annexin V/propidium iodide staining, reactive oxygen species production. CsA prevented parasite oxidative stress damage as it significantly inhibited DNA degradation, cytochrome c translocation to cytosol and TcPARP cleavage. The calcein-AM/CoCl2 assay, used as a selective indicator of mPTP opening in mammals, was also performed in T. cruzi parasites. H2O2 treatment decreased calcein fluorescence, but this decline was partially inhibited by pre-incubation with CsA. Our results encourage further studies to investigate if there is a mPTP-like pore and a mitochondrial cyclophilin involved in this protozoan parasite.

    D).- Improved Immuno-Detection of a Low-Abundance Cyclophilin Allows the Confirmation of its Expression in a Protozoan Parasite

Patricia L Bustos1*, Alina E Perrone1, Natalia A Milduberger1,2 and Jacqueline Bua1,2
Bustos et al., Immunochem Immunopathol: Open Access 2015, 1:1
http://dx.doi.org/10.4172/icoa.1000103

Abstract:
Protein samples can be challenging to analyze due to the presence of high-abundance proteins masking low-abundance proteins of interest, such as biomarkers and novel physiological mediators. Cyclophilins are chaperones involved in the cis/trans isomerization of peptidyl-prolyl bonds in peptides or proteins and have been found in every organism sequenced to date. Although considerable progress has been made in the characterization of some cyclophilins expressed in diverse parasites invading humans, the main aspects of low-abundance members of this family remain unknown. In the present work, we present that the combined strategy of using more specific antibodies and increasing the presence of subcellular proteins in the sample, allowed us to confirm the expression of a 21.1 kDa cyclophilin for the first time in Trypanosoma cruzi .

    E).- Oxidative stress damage in the protozoan parasite Trypanosoma cruzi is inhibited by Cyclosporin A
    Bustos PL, Perrone AE, Milduberger N, Postan M, Bua J
    Parasitology, Page 1 of 9. © Cambridge University Press 2015 doi:10.1017/S0031182015000232
    Cyclosporin A (CsA) specifically inhibits the mitochondrial permeability transition pore (mPTP).

Abstract
Opening of the mPTP, which is triggered by high levels of matrix [Ca2+] and/or oxidative stress, leads to mitochondrial dysfunction and thus to cell death by either apoptosis or necrosis. In the present study, we analysed the response of Trypanosoma cruzi epimastigote parasites to oxidative stress with 5 mM H2O2, by studying several features related to programmed cell death and the effects of pre-incubation with 1 μM of CsA. We evaluated TcPARP cleavage,DNAintegrity, cytochrome c translocation, Annexin V/propidium iodide staining, reactive oxygen species production. CsA prevented parasite oxidative stress damage as it significantly inhibited DNA degradation, cytochrome c translocation to cytosol and TcPARP cleavage. The calcein-AM/ CoCl2 assay, used as a selective indicator of mPTP opening in mammals, was also performed in T. cruzi parasites. H2O2 treatment decreased calcein fluorescence, but this decline was partially inhibited by pre-incubation with CsA. Our results encourage further studies to investigate if there is a mPTP-like pore and a mitochondrial cyclophilin involved in this protozoan parasite.

    F).- Diagnosis of congenital Trypanosoma cruzi infection: A serologic test using Shed Acute Phase Antigen (SAPA) in mother-child binomial samples.
    Volta BJ, Russomando G, Bustos PL, Scollo K, De Rissio AM, Sánchez Z, Cardoni RL, Bua J
    Acta Trop. 2015 Apr 3; 147:31-37. doi: 10.1016/j.actatropica.2015.03.026. [Epub ahead of print]

Abstract
Chagas congenital infection is an important health problem in endemic and non-endemic areas in which Trypanosoma cruzi-infected women can transmit the parasite to their offspring. In this study, we evaluated the antibody levels against the T. cruzi Shed Acute Phase Antigen (SAPA) in 91 binomial samples of seropositive pregnant women and their infected and non-infected children by ELISA. In 70 children without congenital T. cruzi transmission, the titers of anti-SAPA antibodies were lower than those of their seropositive mothers. In contrast, 90.5% of 21 congenitally infected children, at around 1 month of age, showed higher anti-SAPA antibody levels than their mothers. Subtracting the SAPA-ELISA mother OD value to the SAPA-ELISA child OD allowed efficient detection of most T. cruzi congenitally infected children immediately after birth, when total anti-parasite antibodies transferred during pregnancy are still present in all children born to seropositive women. A positive correlation was observed between parasitemia levels in mothers and infants evaluated by quantitative DNA amplification and anti-SAPA antibody titers by ELISA. As SAPA serology has proved to be very efficient to detect T. cruzi infection in mother-child binomial samples, it could be of extreme help for early diagnosis of newborns, in maternities and hospitals where DNA amplification is not available. This prompt diagnosis may prevent drop out of the long-term follow-up for future diagnosis and may ensure early trypanocidal treatment, which has proved to be efficient to cure infants with congenital Chagas disease.

    G).- Anti-Trypanosoma cruzi effects of cyclosporin A derivatives: possible role of a P-glycoprotein and parasite cyclophilins. 
    Búa J, Fichera LE, Fuchs AG, Potenza M, Dubin M, Wenger RO, Moretti G, Scabone CM, Ruiz AM Parasitology.2008 Feb;135(2):217-28. Epub 2007 Oct 9. 

    Abstract:
    Cyclophilins are target molecules for cyclosporin A (CsA), an immunosuppressive antimicrobial drug. We have previously reported the in vitro anti-Trypanosoma cruzi activity of H-7-94 and F-7-62 non-immunosuppressive CsA analogues. In this work, we continue the study of the parasiticidal effect of H-7-94 and F-7-62 CsA analogues in vitro and in vivo and we analyse 3 new CsA derivatives: MeIle-4-CsA (NIM 811), MeVal-4-CsA (MeVal-4) and D-MeAla-3-EtVal-4-CsA, (EtVal-4). The most efficient anti-T. cruzi effect was observed with H-7-94, F-7-62 and MeVal-4 CsA analogues evidenced as inhibition of epimastigote proliferation, trypomastigote penetration, intracellular amastigote development and in vivo T. cruzi infection. This trypanocidal activity could be due to inhibition of the peptidyl prolyl cis-trans isomerase activity on the T. cruzi recombinant cyclophilins tested. Furthermore, CsA and F-7-62 derivative inhibited the efflux of rhodamine 123 from T. cruzi epimastigotes, suggesting an interference with a P-glycoprotein activity. Moreover, H-7-94 and F-7-62 CsA analogues were not toxic as shown by cell viability and by aminopyrine-N-demethylase activity on mammalian cells. Our results show that H-7-94, F-7-62 and MeVal-4 CsA analogues expressed the highest inhibiting effects on T. cruzi, being promissory parasiticidal drugs worthy of further studies.

 

    3).- PROYECTO MARCADORES GENÉTICOS DE RIESGO VASCULAR DE LA CIUDAD DE BUENOS AIRES.
Director: Fridman Osvaldo mail: Osvaldo.fridman@uai.edu.ar Inicio 2006 y renovación hasta actual

    A).-  Paraoxonase 1 gene polymorphisms and enzyme activities in coronary artery disease and its relationship to serum lipids and glycemia.
    Fridman O1, Gariglio L2, Riviere S3, Porcile R2, Fuchs A3, Potenzoni M2.
    Arch Cardiol Mex. 2016 Sep 15. pii: S1405-9940(16)30075-1. doi: 10.1016/j.acmx.2016.08.001.

    Abstract

    OBJECTIVES:
    Oxidative stress and inflammation are important processes in development of atherosclerosis. Paraoxonase 1 (PON1) is a bioscavenger enzyme associated with inflammation and oxidative stress. We evaluate the association of two single nucleotide polymorphisms in PON1 gene, and enzyme activities with lipid profile and glycemia.
    METHODS:
    This case-control study consisted of 126 patients with coronary artery disease (CAD) and 203 healthy controls. PON Q192R and L55M polymorphisms were detected by real-time PCR. Paraoxonase and arylesterase activities were determined spectrophotometrically. Blood glucose, cholesterol, triglycerides, HDL, and LDL were measured.
    RESULTS:
    PON1 QR192 polymorphism had a major effect on paraoxonase but no effect on arylesterase serum activities. Paraoxonase activity was higher in RR genotype and lowest in QQ genotype. Paraoxonase and arylesterase activities were higher in LL and lower in MM genotypes of PON1 LM55 polymorphism. RQ and LM variants showed intermediate activities between respective homozygous. Elevated concentrations of triglycerides in cases correlate with QQ variant or the presence of M allele. Glucose levels were elevated in cases with QQ variant or with the presence of M allele. Cholesterol and LDL did not show variations in control and cases with any variant of both polymorphisms. HDL is lower in cases with respect to controls independently of genotypes. All differences were significant with p<0.05.
    CONCLUSIONS:
    Our results confirm the relationship between variations in PON1 activities and lipid metabolism, and showed that genetically programmed low PON1 activities would have certain responsibility in the increase in glycemia and concomitantly the aggravation of atherosclerotic disease.

    B).- Evolución clínica y evaluación hemodinámica de pacientes tratados con ivabradina durante la infusión de inotrópicos endovenosos
    Rafael Porcile1, Ricardo L. Levin2, Osvaldo Fridman3, Gabriel Perez Baztarrica4, Ruben Mayer2, Flavio Salvaggio5, Alejandro L. Botbol Insuf. card. [online]. 2015, vol.10, n.3, pp. 119-125. ISSN 1852-3862.
    Resumen
    Objetivo. Evaluar el efecto hemodinamico de la ivabradina utilizada para reducir la taquicardia sinusal durante el tratamiento de la insuficiencia cardiaca avanzada bajo terapia inotrópica.Material y métodos. Entre Enero de 2011 y Marzo de 2015 se trataron con ivabradina prospectivamente pacientesen ritmo sinusal con mas de 100 lpm de frecuencia cardiaca admitidos al area de cardiologia critica por insuficiencia cardiaca estadio D de etiologia isquemico necrotica refractaria al tratamiento oral y endovenoso convencional conindicacion de terapia inotropica endovenosa con, al menos, una sumatoria de 10 γ/Kg/minuto y, al menos, 2,2 litros/ m2 superficie corporal de indice cardiaco. Se excluyeron pacientes en shock o que requirieran asistencia respiratoriamecanica o asistencia circulatoria mecanica. Se realizaron mediciones con cateter de Swan Ganz antes y tres horasdespues de la administracion de 15 mg de ivabradina, via enteral.Resultados. El estudio incluyo a 61 pacientes (39 hombres y 22 mujeres) con edad promedio de 65,8 anos. La fracciónde eyeccion del ventriculo izquierdo fue del 31,8%. La dosis promedio de farmaco inotropico endovenoso fue de15,2 γ/Kg/minuto. Tres horas despues de la ivabradina la frecuencia cardiaca bajo de 121 ・} 6 a 98 ・} 7 (p=0,00002),leve aumento del volumen minuto cardiaco medido por termodilucion de 4597 ・} 550 mL/min a 4825 ・} 535 mL/min (p=0,041). El rendimiento cardiaco evaluado por el indice cardiaco aumento en el limite de la significacion estadisticade 2,21 ・} 0,3 a 2,33 ・} 0,3 L/m2 superficie corporal (p=0,052). El volumen sistolico promedio se incrementosignificativamente de 37,9 ・} 5 a 49,3 ・} 8 mL (p=0,00002). No se observaron diferencias significativas en los registrosde presiones de auricula derecha, ni en las presiones capilares pulmonares, asi como en los calculos de resistenciasvasculares sistemicas y pulmonares. No se observaron efectos adversos de las drogas hasta transcurridas cinco vidasmedias, luego de suspenderla. La mortalidad a 30 dias de este grupo de paciente fue del 8,1%.Conclusiones. La ivabradina es util para moderar la taquicardia sinusal en la insuficiencia cardiaca avanzada durantela terapia inotrópica.Insuf Card 2015;10 (3): 119-125

C).- Comparison of homocysteinemia and MTHFR 677CT polymorphism with Framingham Coronary Heart Risk Score
Luis Gariglio, Stephanie Riviere, Analía Morales, Rafael Porcile, Miguel Potenzoni, Osvaldo Fridman
Arch Cardiol Mex. 2014;84(2):71
OBJECTIVE,The Framingham Coronary Heart Disease Risk Score is an important clinical tool. The aim of this cross-sectional study was to compare plasma homocysteine levels and polymorphism 677CT MTHFR with this score to determine the utility of these new biomarkers in clinical practice.Methods: Plasma homocysteine levels determined by chemiluminescence and polymorphism 677CT MTHFR, detected by PCR-RFLP, were compared with Framingham coronary risk score in a cross-sectional survey on 68 men and 165 women. Results: Coronary heart disease risk augmented with an increase in the quartile of plasma homocysteine. In the 2nd, 3rd and 4th quartile of plasma homocysteine, men showed significantly (P < 0.001) higher risk than women. For the highest quartile of plasma homocysteine, OR of high-risk (10-year risk≥20%) compared with the lowest quartile was 17.45 (95% CI: 5.79---52.01). Frequencies of CT and TT genotype and T allele were not over-represented in the individuals with score≥10%. The higher plasma homocysteine concentrations in individuals with score≥10% with respect to those with low risk (P < 0.005 and P < 0.001) were not due to the presence of T allele. The T allele (CT + TT genotypes) of the MTHFR C677T polymorphism was not significantly associated with an increased risk of coronary disease (OR = 1.09, 95% CI = 0.50---2.39, P = 0.844). Conclusions: The present study demonstrated an association between plasma homocysteine levels and the severity of coronary heart disease estimated with the Framingham coronary risk score, and this association appeared to be independent on the genotype of MTHFR.We postulate that plasma homocysteine is effective enough, considered even in isolation.

D).- Polymorphism with Hypertension in Older Women in a Population of Buenos Aires City Clinical and Experimental
Osvaldo Fridman, Rafael Porcile, Analía V. Morales, Luis O. Gariglio, Miguel A. Potenzoni Paula C.
Turk Noceto Association of Methylenetetrahydrofolate Reductase Gene 677C>T
Hypertension, 2012; Early Online: 1–8 (proof)

Abstract:

 Numerous studies have identified hyperhomocysteinemia as an independent risk factor for coronary artery disease (CAD).Furthermore, influences of polymorphism of methylenetetrahydrofolate reductase (MTHFR) on homocysteine levels (tHcy)are documented. Nevertheless, in Argentina, there is little published work although CAD is extremely common. Our aim was to examine the relationship between the 677C>T polymorphism in the MTHFR gene and tHcy in normotensive (NT) and hypertensive (HT) patients as well as the influence of sex and age. We performed a cross-sectional study on subjects 15 recruited in three health centers located in Buenos Aires city. The diagnosis of hypertension was ascertained on the basis of a long-term antihypertensive treatment. Plasma levels of tHcy and MTHFR polymorphism were determined. The study group included 225 subjects (59 males and 166 females) aged between 18 and 87 years. Smoking habits, history ofvascular disease, diabetes, and tHcy were significantly associated with T allele as hypertension risk factors. The T allele was significantly related with the higher tHcy concentrations observed in (i) men with respect to women (P < .01), (ii) men 20 and women older than 47 years (median) versus younger (P < .05 and P < .001, respectively), (iii) HT women (P < .01), and (iv) older HT women versus NT (P < .01). Our study showed an association between the 677C>T MTHFR polymorphism and tHcy with hypertension that in women is manifested with age. In fact, the differences observed on sex and age could be the result of endocrine activity, as hormonal status may modify the phenotypic expression of this genetic variant.

    E).- Corticoadrenal activity in rat regulates betaine-homocysteine S-methyltransferase expression with opposite effects in liver and kidney.
    Fridman O, Morales AV, Bortoni LE, Turk-Noceto PC, Prieto EA J  Biosci. 2012 Mar;37(1):115-23.

    Abstract :
    Betaine-homocysteine S-methyltransferase (BHMT) is an enzyme that converts homocysteine (Hcy) to methionine using betaine as a methyl donor. Betaine also acts as osmolyte in kidney medulla, protecting cells from high extracellular osmolarity. Hepatic BHMT expression is regulated by salt intake. Hormones, particularly corticosteroids, also regulate BHMT expression in rat liver. We investigated to know whether the corticoadrenal activity plays a role in kidney BHMT expression. BHMT activity in rat kidneys is several orders of magnitude lower than in rat livers and only restricted to the renal cortex. This study confirms that corticosteroids stimulate BHMT activity in the liver and, for the first time in an animal model, also up-regulate the BHMT gene expression. Besides, unlike the liver, corticosteroids in rat kidney down-regulate BHMT expression and activity. Given that the classical effect of adrenocortical activity on the kidney is associated with sodium and water re-absorption by the distal tubule leading to volume expansion, by promoting lesser use of betaine as a methyl donor, corticosteroids would preserve betaine for its other role as osmoprotectant against changes in the extracellular osmotic conditions. We conclude that corticosteroids are, at least in part, responsible for the inhibition of BHMT expression and activity in rat kidneys.
    Marcadores genéticos de riesgo vascular. Polimorfismos de MTHFR y PON1 en una población de la Ciudad de Buenos Aires.

    F).- Association of Methylenetetrahydrofolate Reductase Gene 677C>T Polymorphism with Hypertension in Older Women in a Population of Buenos Aires City

Osvaldo Fridman, Rafael Porcile, Analía V. Morales, Luis O. Gariglio, Miguel A. Potenzoni, Paula C. Turk Noceto
Clinical and Experimental Hypertension, 2012; Early Online: 1–8 Copyright © Informa Healthcare USA, Inc. ISSN 1064-1963 print/1525-6006 online DOI: 10.3109/10641963.2012.690471
We examined the relationship between the 677C >T polymorphism in the MTHFR gene and tHcy in normotensive (NT) and hypertensive (HT) subjects and the influence of sex and age in a cross-sectional study. Smoking habits, history of vascular disease, diabetes, and tHcy were significantly associated with T allele as hypertension risk factors. The T allele was significantly related with higher tHcy in (i) men versus women (P < .01), (ii) men and women older than 47 years versus the younger ones (P < .05 and P < .001, respectively), (iii) HT women versus NT women (P < .01), and (iv) older HT women versus older NT women (P < .01). We found an association between the 677C>T MTHFR polymorphism and tHcy with hypertension that in women is manifested with age.

G).- Paraoxonase: its multiple functions and pharmacological regulation
Fridman O, Fuchs AG, Porcile R, Morales AV, Gariglio LO. Arch Cardiol Mex. 2011 Jul-Sep;81 (3):251-60.

Abstract:
Homocysteine, a non-protein amino acid, important risk factor for atherosclerosis and thrombosis, causes dysfunction of vascular endothelial cells traduced in inadequate vasodilatation mechanism, is pro-inflammatory and induces endoplasmic reticulum stress. The more reactive conformation is the homocysteine thiolactone (HcyT), product to the nonspecific action of methionyl-tRNA synthetase, which is incorporated into proteins by disulfide bonds (S-homocysteinilation) or amide bonds (N-homocysteinilation) affecting protein structure and function leading to cell toxicity, autoimmune responses and atherogenesis. The enzyme paraoxonase-1 (PON1), part of high density lipoprotein (HDL), had been studied only for its ability to hydrolyze organophosphate derivatives. But, more recently it has been attributed other important role. The enzyme activities are involving in protecting against the development of atherosclerosis, by preventing oxidation of lipoproteins and hydrolyze HcyT. There is growing evidence about the protective role of PON1 in vascular disease. Genetic factors (polymorphisms of the PON1), environmental and lifestyle influence their concentration and biological activity, but drugs used as cardioprotectives and lipid-lowering or others, such as antibiotics and steroids, are also important modulators. This review is an updated of the most prominent information on clinical and experimental studies for understanding the role of the PON-1 in the protection against development of atherosclerosis.

H).- Study on homocysteine levels and methylenetetrahydrofolate reductase gene variant (C677T) in a population of Buenos Aires City
 Fridman O, Porcile R, Vanasco V, Junco MN, Gariglio L, Potenzoni MA, Bañes I, Morales A.   Clin Exp Hypertens. 2008 Oct;30(7):574-84.

Abstract 
The substitution of cytosine (C) by thymine (T) at nucleotide 677 of the methylenetetrahydrofolate reductase (MTHFR) gene, which converts an alanine to a valine residue, is a frequent polymorphism with reduced specific activity, associated with moderate increase in plasma homocysteine levels (tHcy) and risk of vascular diseases.OBJECTIVES: This study was designed to investigate an association of this polymorphism with tHcy and vascular risk factors.METHODS: We used a cross-sectional study on subjects affiliated to three health centers from Buenos Aires city. The diagnosis of hypertension was ascertained by patients' clinical history. Only subjects under long-term antihypertensive treatment were included.RESULTS: Samples from 138 physically active individuals (44 men and 94 women) randomly selected were included. The mean tHcy was significantly higher amongst hypertensives (HT) than normotensives (NT). The risk of hypertension was compared in subjects with CC genotype and the combined number of subjects with at least one T allele (CT/TT). There was no significant difference regarding the risk of hypertension between NT and HT groups in the overall sample. However, as obesity is considered a risk factor for hypertension development, when only HT (n = 29) and NT (n = 66) subjects with body mass index below 30 kg/m(2) (BMI<30) were compared, subjects bearing CT/TT presented a significantly higher risk of hypertension than those bearing the CC genotype and significantly higher concentration of tHcy.CONCLUSIONS: Our results indicate an association of hyper-tHcy and MTHFR C677T mutation with hypertension. MTHFR C677T mutation may contribute to hypertension or affect the development of hypertension through hyperhomocysteinemia.

 

    4).- PROYECTO DESARROLLO DE UN ENSAYO COMETA DE REPARACIÓN DEL ADN APLICABE A ESTUDIOS DE GENOTOXICIDAD
    Director: Dr. Antonio Prieto Gonzalez, mail elio.prietto@uai.edu.ar Inicio 2005 y renovaion hasta actual.

    A).- Optimization of Alkaline Single Cell Gel Electropohoresis (Comet Assay) Protocol for Cells from Oral Cavity
    Elio. A. Prieto González, Vanesa. V. Miana and Ana. M. Palermo
    Journal of Advances in Medicine and Medical Research 26(4): 1-14, 2018; Article no.JAMMR.38227 ISSN: 2456-8899

    Abstract
    Comet assays or single cell gel electrophoresis for detection of DNA damage is a test that has been widely utilized to assess the effects of expositions to environmental genotoxicants. The test is also used to evaluate DNA damage related to chronic inflammation or preneoplastic and neoplastic conditions. The cells more frequently assessed in comet assay in humans are the peripheral blood lymphocytes, but there are other cell types that have been considered for that purpose. Among those, buccal cells have received attention for its suitability for comet assay, but there have been relatively few studies on comet assay in buccal epithelial cells. However, there are technical difficulties related to comet assay in buccal epithelial cells that justifies the attempts to develop or optimize protocols that could contribute to standardize the test allowing more widespread use of buccal cells in biomonitoring or clinical trials. In the present work, we compared three protocols: the standard technique of alkaline comet from Tice et al. 1999 and the protocols developed specifically for oral cavity cells from Valverde et al. 1997 and Szeto et al. 2005. We introduced modifications in the protocols related to, a device utilized to scrape the cells from the mucosa, the place and volume of sample enzymatic digestion, trypsin concentration, and also, the times for lysis incubation and unwinding. This modified protocol is a contribution to the optimization of comet assay for buccal cells and contributes to its utilization in biomonitoring human DNA damage.

    B).- DNA Repair Kinetic of Hydrogen Peroxide and UVA/B Induced Lesions in Peripheral Blood Leucocytes from Xeroderma Pigmentosum Patients and Healthy Subjects
    Elio A. Prieto Gonzále, Marta D. Mudry,& Ana M. Palermo
    Journal of Environmental Pathology, Toxicology and Oncology, 33(4):279-293 (2014)
    The objective of the present work was to study the fine kinetics of DNA repair in xeroderma pig­mentosum (XP) syndrome, a complex disorder linked to a deficiency in repair that increases cancer susceptibility. The repair process was evaluated by the comet assay (CA) in cells from 2 XP patients and 9 controls exposed to UVA/B (UVA 366/UVB 280 nm) and H2O2 (150 μM) at temperatures of 4, 15, and 37°C. Samples were taken at 2-min intervals during the first 10 min to analyze the “fine kinetics” repair during the initial phase of the curve, and then at 15, 20, 25, 30, 45, 60, and 120 min. CA evaluation of DNA repair activity points to BER/NER ini­tiation in the first 30 min with both inductors at 37°C and 15°C, but final comet length showed differences ac­cording to treatment. Repair kinetics during 120 min showed a good correlation with clinical features in both XP patients. Differences in final comet length were less pronounced in XP cells treated with H2O2 than with UVA/B, probably because the peroxide produces mainly base oxidation but less bulky lesions; UVA/B generates a mix­ture of both. These findings reinforce the value of CA in testing in DNA repair ability or exposure monitoring.

    C).- Differences in DNA repair kinetics of lesions induced by hydrogen peroxide in lymphocytes from premenopausal breast cancer patients and healthy Women resident in Great Buenos Aires 
    Prieto González EA*, Ortega Soler M, Fuchs A G, Brito R, Palermo AM, Martínez M, Fuentes E.  Journal of Medicine and Medical Science Vol. 2(8) pp. 1036-1046, August 2011

    Abstract
    Nontraditional risk factors in breast cancer have been intensely focused on in recent years. In addition, emphasis has been placed on the gradual variation in preventive paradigms, where identification of susceptible groups of population is of interest. We have evaluated the differences in the repair of oxidative induced DNA damage between pre-menopausal breast tumors patients, and healthy women. Comet assay was chosen as a feasible technique to evaluate DNA repair. Peripheral blood lymphocytes (PBL) were exposed to 100 μM hydrogen peroxide for 5 minutes in ice and then allowed to recover at 37oC for 120 minutes. Results showed that basal DNA damage in patients was not higher than in controls. However, there were significant differences in the amount of DNA repaired at 120 minutes (p <0, 05). The amount of DNA repaired at 120 minutes was 84.5% in the control population versus 63.2% in the premenopausal patient population. Rate of DNA repair was determined in two zones of the curve: from 0 to 30 minutes between the recognition and incision of the lesion when DNA migration reached its maximum and 31 minutes when the comet tail began to shorten until minute 120. The slope of DNA increase in the comet tail during the first ten minutes was significantly lower in patients (mcontrol=10.99 vs mpatients=4, 34), Student t test (p< 0.05), while no differences were found during rejoining. We conclude that comet assay is able to discriminate DNA repair efficiency between breast cancer patients and healthy women. Available online@ http://www.interesjournals.org/JMMS

    D),. Coelomocyte biomarkers in the earthworm Eisenia fetida exposed to 2,4,6-trinitrotoluene (TNT).
     Fuchs J, Piola L, González EP, Oneto ML, Basack S, Kesten E, Casabé N.  Environ Monit Assess. 2011 Apr;175(1-4):127-37. Epub 2010 May 30.

    Abstract
     Contamination by 2,4,6-trinitrotoluene (TNT) is a global environmental problem at sites of former explosive production, handling, or storage, and could have deleterious consequences for human and ecological health. We investigated its sublethal effects to Eisenia fetida, using two nonspecific biomarkers. In coelomocytes of earthworms exposed 24, 48, or 72 h, we evaluated DNA damage (comet assay) and neutral red retention time (NRRT), using the filter paper contact test. Both percentage of damage (D%) and calculated damage index showed significant DNA damage at almost all concentrations, at all time points assayed. Along exposure time, two different patterns were observed. At the lower TNT concentrations (0.25-0.5 μg/cm2) an increased DNA migration at 48 h, with a decrease close to initial levels after 72 h exposure, was observed. This decrease could be attributed to activation of the DNA repair system. At higher concentrations (1.0-2.0 μg/cm2), the high DNA damage observed remained constant during the 72 h exposure, suggesting that the rate of DNA repair was not enough to compensate such damage. Analysis of NRRT results showed a significant interaction between time and treatment. After 48 h, a significant decrease was observed at 4.0 μg/cm2. After 72 h, NRRT presented a concentration-dependent decrease, significantly different with respect to control at 0.5, 1.0, 2.0, and 4.0 μg/cm2. The two assayed methods, performed on the same sample, showed clear responses to sublethal TNT exposure in E. fetida, providing sensitive unspecific biomarkers of cell injury and DNA damage.

    E).- Aminofostine (WR2721) confers DNA protection ti in vivo cisplatin-trated murine peripheral bloodleukocytes 
    Prieto González and A. G. Fuchs, González S. Sánchez  Dose-Response7:234–246, 2009

    Abstract
     Amifostine [S-2-3-aminopropil amino ethyl phosphorotioic acid], a modulator agent for antineoplastic drugs involved in free radicals generation has given controversial results in cisplatin treated leukocytes in vitro. We have evaluated the amifostine protection over leukocytes in vivo, using comet assay. Groups of five OF1 male mice were given one of three doses of amifostine (56, 105 and 200 mg/Kg) after a cisplatin single injection (10 mg/Kg). Serum malonyldialdehide levels, catalase and superoxide dismutase activity were also evaluated. Amifostine showed significant DNA protection (p< 0.01) at the two lower doses evaluated. Malonyldildehide decreased in all amifostine treatments with respect to cisplatin while antioxidant enzyme activities remained unchanged. However, DNA migration increased with the highest amifostine dose; in fact highest dose of amifostine did no protect damage caused by cisplatin this result have implications on amifostine treatment schedules in clinical practice. Free PMC Article.

    F).- Indicadores de estrés oxidativo sistémico y niveles de ozono troposférico en trabajadores agrícolas de dos localidades de la V Región de Chile.

María Eliana Hidalgo L.1, Paola Olivares V.2, Reinaldo Cornejo D.2, Ernesto Fernández B.2, Marcelo Corral F.3, Enrique Cabrera1 Enzo Faccilongo 4 y Elio Antonio Prieto González.*5
Publicacion año 2009
Introducción En la Quinta región de Chile, la contaminación atmosférica por ozono es un tema relevante a partir de la instalación de las Centrales Termoeléctricas en la ciudad de Quillota en 1997. Esta situación que ha propiciado el aumento de la formación de ozono (O3) y otros agentes oxidantes. A lo anterior se agrega la presencia en la desembocadura del río Aconcagua de la Refinería de Petróleos de Con-Con (RPC), la que genera contaminantes oxidantes que son llevados por el viento valle arriba. . Actualmente se cuenta con monitoreo continuo de NOx, O3 y otros contaminantes, principalmente dióxido de azufre (SO2), monóxido de carbono (CO) y compuestos orgánicos volátiles (COV) Los datos reportados por estas redes de monitoreo indican niveles de contaminación de ozono que alcanzan el 80% de la norma vigente de calidad del aire (128 mg/m3N como promedio horario), habiendo registrado valores que podrían indicar una zona latente en la localidad de Hijuelas, mientras que en san Pedro los niveles de ozono se mantuvieron dentro de los límites aceptados.

G).- Deterioro genómico y manipulación genética. Desequilibrio en la prioridad de las agendas públicas 
Elio A. Prieto González   Acta Bioethica; Vol. 13/2 2007 p. 223-231 ISSN 1726-5697

Resumen Se analiza el desequilibrio en el tratamiento de dos temas que atañen a la conservación de la integridad del genoma humano: las tecnologías de manipulación genética y el deterioro genómico provocado por la contaminación ambiental. Las carencias educativas, la falta de información asentada en los hechos y un manejo sensacionalista en los medios, entre otros factores, desajustan las agendas mediáticas con las necesidades públicas, lo que desemboca en una falta de conciencia ciudadana acerca de las verdaderas amenazas a las que está expuesto el material genético y los riesgos de salud que ello implica. http://www.revistas.uchile.cl/index.php/AB/article/viewArticle/16558

 

5).- PROYECTO CULTIVO DE PROTOESCOLESES Y APLICACIÓN DE DIFERENTES DROGAS ANTIPARASITARIAS.        Directora: Dra Alicia G Fuchs, mail Alicia.Fuchs@uai.edu.ar Inicio septimbre 2006 y renovacion hasta  actual.

A) .- Morphological and biological characterization of cell line developed from bovine Echinococcus granulosus.Echeverría CI, Isolabella DM, Prieto Gonzalez EA, Leonardelli A, Prada L, Perrone A, FuchsAG         
In Vitro Cell Dev Biol Anim.2010 Oct;46(9):781-92. Epub 2010 Sep 16.

Abstract
 
The taeniid tapeworm Echinococcus granulosus is the causative agent of echinococcal disease, a major zoonosis with worldwide distribution. Several efforts to establish an in vitro model of E. granulosus have been undertaken; however, many of them have been designed for Echinococcus multilocularis. In the present study, we have described and characterized a stable cell line obtained from E. granulosus bovine protoscoleces maintained 3 yr in vitro. Growth characterization, morphology by light, fluorescent and electronic microscopy, and karyotyping were carried out. Cell culture origin was confirmed by immunofluorescent detection of AgB4 antigen and by PCR for the mitochondrial cytochrome c-oxidase subunit 1 (DCO1) gene. Cells seeded in agarose biphasic culture resembled a cystic structure, similar to the one formed in secondary hosts. This cell line could be a useful tool to research equinococcal behavior, allowing additional physiological and pharmacological studies, such as the effect of growth factors, nutrients, and antiparasitic drugs on cell viability and growth and on cyst formation.

B).- Propiedad Intelectual: INPI P-090102320 “Línea cellular de Protoescólices de Echinococcus SPP. Procedimiento para lo obtener estructuras quísticas y método para evaluar la actividad de drogas antiparasitarias” aprobado en primera instancia 2011.
Obtenido el subsidio PARA ACTIVIDADES DE COOPERACIÓN INTERNACIONAL

C).- CONICET Convenio  Marco : DFG - ALEMANIA título: “Establecimiento y optimización de modelos in vivo in vitro de Echinococcus granulosus y E. multilocularis  para el estudio comparativo de moléculas de secreción y de membrana como posibles blancos de terapia y diagnóstico de la hidatidosis quística y alveolar” Investigadores (Argentina) Dra Rosenzvit, Mara Cecilia, Dr DENEGRI, Guillermo María y Fuchs, Alicia Graciela (Alemania):Dr Brehm, Klaus   (Associate Professor for Medical Parasitology; Molecular Helminthology Research group leader at the University of Wuerzburg; Chairman of the informal WHO working group "Echinococcus basic biology”) año 2008.

D).- CONVENIO DE COOPERACION con Laboratorios Gador SA Proyecto Efectos de los bifosfonatos sobre el Echinococcus granulosus en su forma de metacestode.  Inicio 2009  y continua Subproyecto Caracterización bioquímica y genética de las células obtenidas a partir del protoescólices del Echinococcus granulosus, inicio año 2011

E).- Proline modulates the effect of bisphosphonate on calcium levels and adenosine triphosphate production in cell lines derived from bovine Echinococcus granulosus protoscoleces.
Fuchs AG, Echeverría CI, Pérez Rojo FG, Prieto González EA, Roldán EJ.J Helminthol. Journal of Helminthology (2014) vol. 88, pag.459-467

Source
Centro de Altos Estudios en Ciencias Humanas y de la Salud (CAECIHS), Universidad Abierta Interamericana (UAI), Avenida Montes de Oca 745, (C127OAAH), Buenos Aires, Argentina.
Abstract
Bisphosphonates have been proposed as pharmacological agents against parasite and cancer cell growth. The effect of these compounds on helminthic cell viability and acellular compartment morphology, however, has not yet been studied. The effects of different types of bisphosphonates, namely etidronate (EHDP), pamidronate (APD), alendronate (ABP), ibandronate (IB) and olpadronate (OPD), and their interaction with amiloride, 1,25-dihydroxycholecalciferol (D3) and proline were evaluated on a cell line derived from bovine Echinococcus granulousus protoscoleces (EGPE) that forms cystic colonies in agarose. The EGPE cell line allowed testing the effect of bisphosphonates alone and in association with other compounds that could modulate calcium apposition/deposition, and were useful in measuring the impact of these compounds on cell growth, cystic colony formation and calcium storage. Decreased cell growth and cystic colony formation were found with EHDP, IB and OPD, and increased calcium storage with EHDP only. Calcium storage in EGPE cells appeared to be sensitive to the effect of amiloride, D3 and proline. Proline decreased calcium storage and increased colony formation. Changes in calcium storage may be associated with degenerative changes of the cysts, as shown in the in vitro colony model and linked to an adenosine triphosphate (ATP) decrease. In conclusion, bisphosphonates could be suitable tempering drugs to treat cestode infections.

F).- Solanesyl diphosphate synthase, an enzyme of the ubiquinone synthetic pathway, is required throughout the life cycle of Trypanosoma brucei.
Lai DH, Poropat E, Pravia C, Landoni M, Couto AS, Pérez Rojo FG, Fuchs AG, Dubin M, Elingold I, Rodríguez JB, Ferella M, Esteva MI, Bontempi EJ, Lukes J.

Abstract
Ubiquinone 9 (UQ9), the expected product of the long-chain solanesyl diphosphate synthase (TbSPPS), has a central role in reoxidation of reducing equivalents in the mitochondrion of Trypanosoma brucei. The ablation of TbSPPS gene expression by RNAi increased the generation of reactive oxygen species and reduced cell growth and oxygen consumption. The addition of glycerol to the culture medium exacerbated the phenotype by blocking the endogenous generation and excretion of UQ9. The participation of TbSPPS in UQ synthesis was further confirmed by growth rescue using UQ with 10 isoprenyl subunits (UQ10). Furthermore, the survival of infected mice was prolonged upon the down-regulation of TbSPPS and/or the addition of glycerol to drinking water. TbSPPS is inhibited by 1-[(n-oct-1-ylamino)ethyl] 1,1-bisphosphonic acid, and treatment with this compound was lethal for the cells. The findings that both UQ9 and ATP pools were severely depleted by the drug, and that exogenous UQ10 was able to fully rescue growth of the inhibited parasites, strongly suggest that TbSPPS and UQ synthesis were the main targets of the drug. These two strategies highlight the importance of TbSPPS for T. brucei, justifying further efforts to validate it as a new drug target.
Eukaryot Cell. 2013 Dec 27. 

G).- ANR 800 - convenio Plena Salud SA 2014 Prueba de diagnostico rápido (PDR) de infecciones crónicas parasitarias. Caso de Hidatidosiscistica causada por metacestodes (larva) de Echinococus granulosus.

 

6).- PROYECTO FACTORES PARÁCRINOS INVOLUCRADOS EN LAS ALTERACIONES CELULARES DEL INTESTINO DIABÉTICO. ESTUDIO IN VITRO.
Directores: Dra. Sanchez Sara S. (UNT) y Dra. Fuchs Alicia G.

A).- Extracellular matrix remodeling and TGF-β1/Smad signaling in diabetic colon mucosa.
D'Arpino MCFuchs AGSánchez SSHonoré SM
Cell Biol Int. 2017 Dec 11. doi: 10.1002/cbin.10916. [Epub ahead of print]

Abstract:
Diabetes is associated with metabolic and functional alterations in the gut. Using an experimental model of streptozotocin (STZ)-induced diabetes in rodents, we analyzed the extracellular matrix (ECM) and TGF-β/Smad signaling in the colon mucosa. Male rats were divided into normal control, diabetic and insulin treated diabetic groups during 4 and 9 weeks. Sirius red staining showed marked increase in the extracellular matrix deposition in diabetic mucosa. High levels of fibrillar collagen (I and III) and fibronectin mRNAs were also detected with an imbalance between MMPs/TIMPs activities. Moreover, an increased mesenchymal cell proliferation together with an enhanced expression of myofibroblasts markers vimentin and α-SMA were observed. TGF-β/Smad signaling-related genes were determined using RT-PCR, western blotting, and immunohistochemistry. Diabetic rats showed a significant up-regulation of TGF-β1, TGF-β receptors and the effectors p-Smad2/3 in the mucosa compared with control rats. Insulin treatment attenuated the stimulating effect of diabetes on colon ECM deposition and TGF-β/Smad signaling. In conclusion, the overall results showed a deregulation of the TGFβ1 pathway associated with the appearance of myofibroblasts and the accumulation of ECM in the mucosa of diabetic colon. These data provide the first in vivo evidence that TGF-β1/Smad is a key component of intestinal tissue remodeling in diabetes.

 

7).- PROYECTO ASPECTO FIBROGÉNICO DE LAS CÉLULAS MESENQUIMÁTICAS PERIFÉRICAS EN PACIENTES CON ÚLCERA VENOSA CRÓNICA
Directora: Crocco Melisa y Fuchs Alicia 01/04/2013 - 30/09/2014

A).- Can Venous Ulcer Size be Associated with the Healing Potential of Serum? Pilot Study

Melisa C Crocco1*, Diana M Kelmansky2, Roberto H Mengarelli 3,4, Roberto Cherjovsky 3,4, Alicia G Fuchs1
ARC Journal of Dermatology Volume 2 Issue 2, 2017, PP 9-15 ISSN No. (Online) 2456-0022 DOI: http://dx.doi.org/10.20431/2456-0022.0202003 www.arcjournals.org
Abstract:
Ulcer size may be associated to slow healing. If this association is true, it could help with diagnosis and subsequent treatment of chronic venous ulcer (CVU). The aim of this work was to study the relationship of ulcer size of CVU patients with the healing potential contained in their serum. This potential was measured directly on patients’ sera through a cytometric technique for the content of Vascular Endothelial Growth Factor (VEGF) and Fibroblast Growth Factor (FGF). These factors are responsible for revascularization, fibroblast proliferation and collagen deposition. Further, the effect of serum on proliferation and collagen deposition was evaluated in vitro cultures.
The results of the in vitro experiment highlighted the isolated effects of homolateral venous serum factors on Vero cells line not undergoing any inflammation. Ulcer size did not influence the characteristics of sera from CVU patients. In the discussion our results are evaluated in the context of recent research regarding ulcer sizes.

 

8).- PROYECTO: PAPEL DE LAS POLIAMINAS EN LA INFECCIÓN POR TRYPANOSOMA CRUZI. PROINFLAMATORIAS P ANTIINFLAMATORIAS?
Directora Martha Schwarcz  Inicio 2004 y finalización 2015

A) Urban Chagas disease in children and women in primary care centres in Buenos Aires, Argentina
Mem Inst Oswaldo Cruz, Rio de Janeiro: 1-5, 2015
Guillermo Moscatelli1/+, Ada Berenstein2, Ana Tarlovsky3, Susana Siniawski2, Miguel Biancardi1,
Griselda Ballering1, Samanta Moroni1, Marta Schwarcz4, Susana Hernández4,
Facundo García-Bournissen1, Andrés Espejo Cozzi4, Héctor Freilij1, Jaime Altcheh1

Abstract:
The primary objective of this study was to estimate the prevalence of this disease in women of childbearing age and children treated at health centres in underserviced areas of the city of Buenos Aires. Demographic and Chagas disease status data were collected. Samples for Chagas disease serology were obtained on filter paper and the reactive results were confirmed with conventional samples. A total of 1,786 subjects were screened and 73 positive screening results were obtained: 17 were from children and 56 were from women. The Trypanosoma cruzi infection risk was greater in those individuals who had relatives with Chagas disease, who remember seeing kissing bugs, who were of Bolivian nationality or were born in the Argentine province of Santiago del Estero. The overall prevalence of Chagas disease was 4.08%. Due to migration, Chagas disease is currently predominantly urban. The observed prevalence requires health programme activities that are aimed at urban children and their mothers. Most children were infected congenitally, which reinforces the need for Chagas disease screening of all pregnant women and their babies in Argentina. The active search for new cases is important because the appropriate treatment in children has a high cure rate.

B).- Hexachlorobenzene-induced early changes in ornithine decarboxylase and protein tyrosine kinase activities, polyamines and c-Myc, c-Fos and c-Jun proto-oncogenes in rat liver
Hernandez SM, Kolliker-Frers RA, Sanchez MS, Razzitte G, Britos RD, Fuentes ME, Schwarcz de Tarlovsky MNx. Acta Trop. 2009 Mar;109(3):219-25. Epub 2008 Nov 25.

Abstract
 Serum from asymptomatic or symptomatic (with cardiovascular manifestations) chagasic patients depleted of the complement system displayed an antiproliferative effect on Trypanosoma cruzi epimastigotes, RA strain, when added to the growth medium. This effect was also observed when patient's serum was depleted of specific antibodies. The antiproliferative effect was both time and concentration dependent. It was confined to the non-dialyzable, high molecular weight, fraction of the serum. This effect was abrogated by allopurinol and catalase, and enhanced by N-ethylmaleimide. Xanthine oxidoreductase and xanthine oxidase activities were increased in the chagasic sera, while catalase activity remained unchanged. Parasites exposed to chagasic sera showed a decrease in Fe/superoxide dismutase activity as well as an increase in membrane lipoperoxidation. Our data provides evidence to support the idea that the antiproliferative activity observed in sera from chagasic patients may be due, at least partially, to a direct effect of hydrogen peroxide on the epimastigotes of T. cruzi. The increase of hydrogen peroxide to antiproliferative levels might result from an increase in xanthine oxidase activity in the serum of patients infected with the parasite.

C).- Subsidio PICTO CRUP Convocatoria PICTO 2005 CRUP Proyectos financiados - Resolución Directorio de la ANPCyT Nº 054/2007 31428 Cs. Médicas ENFERMEDAD DE CHAGAS. ESTUDIO DE LA PREVALENCIA DE LA ENFERMEDAD EN LA VILLA 20 Y CARACTERIZACION DEL EFECTO LITICO DE LOS SUEROS DE LOS PACIENTES CHAGASICOS PARA SU APLICACION DIAGNOSTICA Y PRONOSTICA Schwarcz, Martha Norma Universidad Abierta Interamericana

D).- Hexachlorobenzene-induced early changes in ornithine decarboxylase and protein tyrosine kinase activities, polyamines and c-Myc, c-Fos and c-Jun proto-oncogenes in rat liver
Randi AS, Hernandez S, Alvarez L, Sanchez M, Schwarcz M, Kleiman d Pisarev DL .  Toxicol Sci. 2003 Dec;76(2):291-8. Epub 2003 Nov 4. 

Abstract
Hexachlorobenzene (HCB) is a lipophilic chemical compound that is widely distributed in the environment. HCB is known to cause liver tumors in experimental animals. In the present study the in vivo effect of HCB treatment on ornithine decarboxylase (ODC) and protein tyrosine kinase (PTK) activities, free polyamine content, and c-Myc, c-Fos, and c-Jun protein levels in rat liver were investigated. HCB (1000 mg/kg body weight) increased hepatic immunodetectable c-Myc, c-Fos, and c-Jun levels after 6 h, and ODC activity and spermine and putrescine content after 18 and 24 h, while maximum stimulation of PTK activity occurred at 12 h. PTK and ODC activities varied in a dose-dependent manner. The time-course of c-Myc, c-Fos, and c-Jun protein levels was different for each proto-oncogene. They were all elevated at the second day of treatment, while only c-Fos and c-Jun remained elevated after 10 days of HCB exposure. These data jointly suggest that the increase in ODC activity may be the consequence of proto-oncogene induction. The alterations in PTK activity suggest that the growth factor signal transduction pathway may be involved in the regulation of the proto-oncogene levels or/and ODC activity. The decrease in PTK activity after the first day, even in the presence of alpha-D-Difluoromethylornithine (DFMO), an inhibitor of ODC activity, suggests that it is not regulated by polyamines. These results may be relevant to the early molecular events involved in HCB tumor promoter activity in rat liver.

 

9).- PROYECTO: EVALUACIÓN DE LA SUSCEPTIBILIDAD A DROGAS ANTICHÁGASICAS EN RATONES C3H/HEN INFECTADOS CON LA CEPA T. CRUZI NICARAGUA DE RECIENTE AISLAMIENTO DE ZONA ENDÉMICA.
Directora: Dra Laura E Fichera  mail: lfichera@yahoo.com Inicio 2007 y finalización 2014.

A).- Combined treatment with benznidazole and allopurinol in mice infected with a virulent Trypanosoma cruzi isolate from Nicaragua.

Grosso NL, Alarcon ML, Bua J, Laucella SA, Riarte A, Fichera LE.(Instituto Nacional de Parasitología Dr M. Fatala Chaben, ANLIS Malbran, en convenio con el Caecihs de la Universidad Abierta interamericana)    Published online: Parasitology. 2013 Mar 18:1-9. https://doi.org/10.1017/S0031182013000176

Abstract
SUMMARY We evaluated the effect of chemotherapy with a sequential combined treatment of a low dose of benznidazole and allopurinol, in different schedules of administration, in experimental models of acute and chronic Trypanosoma cruzi infection. Mice were infected with Nicaragua T. cruzi isolate, a virulent parasite from an endemic area of Nicaragua, genotyped as TcI (Grosso et al. 2010). We assessed survival rate, IgG levels, histopathological studies and quantified parasitaemia. A 15% survival rate was recorded in untreated mice during the acute phase of T. cruzi infection. Allopurinol administered immediately after benznidazole treatment was able to reduce parasitaemia and attenuate tissue damage by reducing inflammation. Trypanosoma cruzi-specific antibodies also decreased in 40-50% of the treated mice. The addition of allopurinol during the chronic phase showed the highest beneficial effect, not only by reducing parasitaemia but also by lowering the degree of inflammation and fibrosis.

B).- Trypanosoma cruzi: Biological characterization of a isolate from an endemic area and its susceptibility to conventional drugs 
Noelia L. Grosso, Jacqueline Bua , Alina E. Perrone, Mariela N. Gonzalez, Patricia L. Bustos, Miriam Postan, Laura E. Fichera  Parasitology. 2008 Feb;135(2):217-28. Epub 2007 Oct 9.

Abstract
We describe some biological and molecular characteristics of a Trypanosoma cruzi isolate derived from aTriatomine captured in Nicaragua. PCR based typification showed that this isolate, named Nicaragua, belonged to the lineage Tc I. Nicaragua infected culture cells were treated with allopurinol, showing different behavior according to the cellular compartment, being cardiomyocyte primary cultures more resistant to this drug. The course of the infection in a mice experimental model and its susceptibility to benznidazole and allopurinol was analyzed. In benznidazole treatment, mice reverted the high lethal effect of parasites during the acute infection, however, a few parasites were detected in the heart of 88% of mice 1 year post-infection. Since T. cruzi is a heterogeneous species population it is important to study and characterize different parasites actually circulating in humans in endemic areas. In this work we show that T. cruzi Nicaragua isolate, is sensitive to early benznidazole treatment.

 

10).- PROYECTO :RECEPTORES HORMONALES  EN TUMORES HIPOFISARIOS
Director: Dr Jose Burdman mail:Jose.Burdman@uai.edu.ar  inicio 2006 finalización 2009.

A).- T3 receptors in human pituitary tumors
Machiavelli GA, Pauni M, Heredia Sereno GM, Szijan I, Basso A, Burdman JA..Neurol Res. 2009 Nov;31(9):928-30. Epub 2009 Jan 9.

OBJECTIVE: The purpose of this work was to investigate the synthesis of T3 receptors in human tumors of the anterior pituitary gland, its relationship with the hormone synthesized and/or secreted by the tumor and the post-surgical evolution of the patient. METHODS: Patients were evaluated clinically and by magnetic nuclear resonance to classify the adenoma according to their size. Hormonal concentrations in sera were determined by radioimmunoassay. Immunohistochemistry of the pituitary hormones was performed in the tumors. Tumors were obtained at surgery and immediately frozen in ice, transported to the laboratory and stored at -70 degrees C. Reverse transcription was performed with purified RNA from the tumors. RESULTSOut of 33 pituitary tumors, 29 had RNA for T3 receptors synthesis (88%). They were present in different histological specimens, the tumors were grades 1-4 according to their size, and there was no relationship between the size of the tumor and the presence of T3 receptor RNAs. The post-surgical evolution of the patient was mostly dependent on the size and not on the presence of T3 receptors.DISCUSSION:The presence of thyroid hormone receptors in pituitary tumors is in line with two important characteristics of these tumors: they are histologically benign and well differentiated.

B).- Estrogen receptors in human pituitary tumors 
Burdman JA, Pauni M, Heredia Sereno GM, Bordón AE. Horm Metab Res. 2008 Aug;40(8):524-7. Epub 2008 Apr 9.

Abstract
 
The relationship between the presence of estrogen receptors in pituitary adenomas and the post surgical evolution of the patients in order to find another prognostic parameter for these tumors have been studied to improve the treatment selection. Estrogen receptors were studied by immunocytochemistry in histological sections of paraffin embedded 42 pituitary adenomas. Only 19% of these tumors were positive for estrogen receptors. As expected, the higher concentration (60%) was found in prolactin secreting adenomas, although we found estrogen receptors in one somatotroph and in one nonsecreting. The most aggressive tumors were those negative for estrogen receptors within the prolactinomas and the positive somatotrophinoma. The results of this work suggest that the determination of estrogen receptors in pituitary tumors might help as a prognostic factor in these adenomas.

C).- Telomerase activity in fine needle aspiration biopsy samples: application to diagnosis of human thyroid carcinoma
 Guerra LN, Miler EA, Moiguer S, Karner M, Orlandi AM, Fideleff H, Burdman JA.. Clin Chim Acta. 2006 Aug;370(1-2):180-4. Epub 2006 Mar 6. Erratum in Clin Chim Acta. 2007 Sep;384(1-2):188.
BACKGROUND: 
The diagnosis of thyroid follicular carcinoma by fine needle aspiration biopsy is a well known problem in thyroid pathology. METHODS: We evaluated telomerase activity (TA) in 85 fine needle aspiration biopsy (FNAB) samples from patients with thyroid nodules. Surgery samples from patients with tumor or follicular adenomas were also analyzed.RESULTS: Twenty of the FNAB samples corresponded to carcinomas and were positive to telomerase assay (TA >10 Units). Among them, 4 follicular carcinomas and 1 papillary carcinoma were labeled as indeterminate by FNAB cytological examination. Four percent false positive cases and no false negative cases for TA in FNABs were reported. FNAB samples from follicular adenomas were diagnosed as indeterminate by cytological examination, but they showed no detectable TA. Tumor tissues from patients with follicular or papillary thyroid carcinomas presented TA >10 Units, whereas follicular adenoma tissues (benign nodules) showed no TA.CONCLUSION: Our results showed a good correlation between TA in FNAB samples and tumor/nodule thyroid tissue. This suggested that use of TA as a biological marker of malignancy might be a useful tool in the diagnosis of follicular thyroid carcinomas or follicular thyroid adenomas using FNAB sample

D).- Antioxidants and methimazole in the treatment of Graves' disease: effect on urinary malondialdehyde levelsGuerra LN, Ríos de Molina Mdel C, Miler EA, Moiguer S, Karner M, Burdman JA . Clin Chim Acta. 2005 Feb;352(1-2):115-20.
BACKGROUNDWe have postulated that metabolic oxidation could be the source of signs and symptoms of hyperthyroidism. The present study was designed to evaluate urinary malondialdehyde levels in Graves' disease and compare this oxidative stress biomarker with the clinical evolution of patients suffering this illness. METHODS:  We evaluated the concentration of urinary and serum malondialdehyde (MDA) in 36 patients with Graves' disease. Patients were treated with the antithyroid drug methimazole (MMI; Group A) or antioxidant mixture (200 mg vitamin E, 3 mg beta-carotene, 250 mg vitamin C, 1 mg Cu, 7.5 mg Zn, 1.5 mg Mn, and 15 microg Se; Group B). RESULTS: MDA concentrations were higher in hyperthyroid patients compared to euthyroid controls, and a positive correlation was observed between serum and urinary MDA levels. Group A decreased urinary MDA to control values. There was a positive correlation between the clinical score and the heart rate of patients with urinary MDA before and during the treatment with MMI (Group A). Similar results were observed after treatment with the antioxidant mixture.CONCLUSIONS: Urinary MDA might be a good parameter in the follow-up of patients during MMI treatment. We proposed that oxidative stress correlates with signs and symptoms of hyperthyroidism.

 

11).- PUBLICACIÓN FUERA DE PROYECTO

A).- Ensayo cometa en células de la mucosa bucal para la evaluación del daño al ADN asociado a lesiones inflamatorias o a la exposición a genotóxicos
Miana, Vanesa & Gonzalez, Elio A.
Revista Argentina de Cancerologia. I. 44-47. (09-2017).

Abstract
El ensayo del cometa alcalino o electroforesis en gel de células individuales (SCG), en células de la mucosa oral ha sido propuesto como una variante al uso de los tradicionales linfocitos de sangre venosa o capilar periférica, pero es además una forma de evaluar directamente el daño genético en las células epiteliales. Se aplicó un protocolo en el que se realizaron digestiones sucesivas de las células con tripsina y proteinasa K. Se ajustaron los tiempos y velocidades de centrifugación. La digestión de la suspensión celular permitió obtener cometas con los contornos más nítidos y en consecuencia más fácilmente evaluables. Optimizando esta herramienta para la evaluación de células bucales se puede obtener información directa de los niveles de daño y reparación del ADN en las células de la mucosa oral lo que aportará unas mejores oportunidades de clasificación de las lesiones bucales que pueden preceder la aparición de cáncer y en consecuencia puede operar como un biomarcador de susceptibilidad para la categorización de los pacientes atendiendo al nivel de daños en el material genético de las células epiteliales de la mucosa oral.

 

B).- B cells inhibit the antitumor immunity against an established murine fibrosarcoma.
Maglioco A;Machuca DG, Badano MN,Nannini P, Camerano GV, Costa H,  Meiss  R, , Ruggiero R,, Giordano M, Dran G
Oncol Lett. 2017 May;13(5):3225-3232. doi: 10.3892/ol.2017.5810. Epub 2017 Mar 6.

Abstract:

Despite the classic role of B cells in favoring the immune response, an inhibitory action of B lymphocytes in tumor immunity has emerged in certain studies. In methylcolanthrene-induced murine fibrosarcoma (MCC), the loss of immunogenicity and the establishment of tolerance are paralleled by systemic immune suppression and the appearance of B+IL-10+ cells in tumor-draining lymph nodes. The present study aimed to assess the role of the B+IL-10+ cell population in the immune evasion and tolerance induced by MCC through the depletion of B cells in mice at various times of tumor progression: Prior to or subsequent to tumor implantation. Tumor growth and immunological parameters were evaluated. B cell depletion prior to tumor inoculum enhanced tumor growth, initiating the onset of the tumor-induced systemic immune response; however, an increase in the T regulatory cells (Tregs) at the tumor-draining lymph node could account for tumor exacerbation. B cell depletion once the tumor was established resulted in decreased tumor growth and a delayed onset of tolerance. Additionally, B cell absence exacerbated T cell dependent-tumor rejection, reduced Tregs and increased cytotoxic CD8+ T cells. In vitro analysis showed a direct effect of B cells upon T cell proliferation. In conclusion, B cell depletion exerts opposite effects when performed prior to or subsequent to tumor implantation. In this initially immunogenic tumor, B cell absence would delay the establishment of immunological tolerance probably by unmasking a pre-existing antitumor response. The present findings elucidate the convenience of modulating B cells in the development of future and more effective immunotherapies against cancer.

 

C).- Student Research Work and Modeled Situations in Order to Bridge the Gap between Basic Science Concepts and Those from Preventive and Clinical Practice. Meaningful Learning and Informed beneficience
Elio A. Prieto González   Email:  Elio.Prietto@vaneduc.edu.ar , ambiengrup@yahoo.com
CE journal Vol.7 No.7, May 2016  DOI: 10.4236/ce.2016.77099

Abstract
Meaningful learning of basic science concepts is a difficult goal to reach among students from different health related university careers. We present an integrative approach based in different educational strategies like problem based, and situated learning as well as the use of models and organizers. Three cases from Medicine, Nursing and Nutrition show the difficulties in the comprehension and integration of basic and applied knowledge as well as the educational approaches adopted and the evolution of students. There is a discussion on the ethical relevance of deep basic and applied knowledge in the right solution of problems posed in class that attempt to model real life scenarios. There is a term introduced in this paper: informed beneficence. This concept   express the assumption  that the professional fulfillment of the ethical principle of beneficence is linked  to knowledge and skills to propose appropriate  solutions to individual or collective health problems.

 

D).- Treatment and post-treatment with lonidamine in human colon carcinoma HT-29 cell line.
 Fuchs AG.Medicina (B Aires). 2008;68(1):13-22. 

Abstract:
Lonidamine (1-[2,4-dichlorophenyl methyl]-1H indazole-3-carboxylic acid), Ind, is an antitumoral drug acting on mitochondria and glucose metabolism. Cell growth and metabolic effects of Ind and drug post-treatment effect were investigated in undifferentiated HT-29 human colonic carcinoma cell line which requires high glucose medium concentration for growth. 0.2 mM Ind significantly decreased cell spreading and growth in monolayer or agar cell culture. After drug treatment cell growth was reestablished to control value within 24 h. Ind modified glycoconjugates and mannose-receptor distribution (analyzed by confocal microscopy), while glucose-glycogen and protein synthesis were not affected, these being the possible reasons for the fast reversible effect.  [PubMed - indexed for MEDLINE]

 

E).-  A New Quantitative Method to Determine the Uptake of SPIONs in Animal Tissue and Its Application to Determine the Quantity of Nanoparticles in the Liver and Lung of Balb-c Mice Exposed to the SPIONs
R. D. Zysler1_ ∗, E. Lima, Jr1, M. Vasquez Mansilla1, H. E. Troiani1, M. L. Mojica Pisciotti1, P. Gurman2, A. Lamagna2, and L. Colombo
Centro Atómico Bariloche and Instituto Balseiro/CONICET, (8400) S. C. de Bariloche, RN, Argentina 2Departamento de Micro y Nanotecnología, Centro Atómico Constituyentes, Av. Gral. Paz 1499, (1650) San Martín, BA, Argentina 3Instituto de Oncología A.H. Roffo, UBA/CONICET/CAECIHS (UAI), Av. San Martín 5481, (1417) CABA, Argentina Journal of Biomedical Nanotechnology Vol. 9, 142–145, 2013 
We propose a new method for determining the quantity of superparamagnetic iron oxide nanoparticles (Fe3O4, SPIONs) embedded in animal tissue using magnetization measurements. With this method, the smallest detectable quantity of magnetite nanoparticles in a tissue sample is ∼1 _g. We showed that this method has proved being efficient. In this study, we focused in determining the quantity of SPION confined in lung and liver tissue of mice injected with ∼13 nm magnetite superparamagnetic nanoparticles. Furthermore, the method allowed us to detect the magnetite nanoparticles present in animal tissues without letting the natural iron ions present in the tissue or blood interfere with the measurements.

 

F).-  Boron Neutron Capture Therapy (BNCT) for liver metastasis in an experimental model: dose-response at 5 weeks follow-up based on retrospective dose assessment in individual rats

Emiliano CC Pozzi, Lic. Biology Veronica A Trivillin, PhD, Lucas L Colombo, MD, PhD, Andrea Monti Hughes, Silvia I Thorp, Lic. Physics, Jorge E Cardoso, Marcela A Garabalino, Ana J Molinari, Elisa M Heber, Paula Curotto, Marcelo Miller, Maria E Itoiz, Romina F Aromando, David W Nigg, Amanda Elena Schwint.
Boron Neutron Capture Therapy (BNCT) was proposed for untreatable colorectal liver metastases. Employing an experimental model of liver metastases in rats we recently demonstrated that BNCT mediated by boronophenylalanine (BPA-BNCT) at 13 Gy prescribed to tumor is therapeutically useful at three weeks follow-up. The aim of the present study was to evaluate dose-response at five weeks follow-up, based on retrospective dose assessment in individual rats. BDIX rats were inoculated with syngeneic colon cancer cells DHD/K12/TRb. Tumor-bearing animals were divided intothree groups, BPA-BNCT (n=19), Beam only (n=8), and Sham (n=7) (matchedmanipulation, no treatment). 
For each rat, neutron flux was measured in situ and boron content was measured in a pre-irradiation blood sample for retrospective individual dose assessment. For statistical analysis (ANOVA), individual data for the BPA-BNCT group were pooled according to absorbed tumor dose, BPA-BNCT I: 4.5 to 8.9 Gy and BPA-BNCT II: 9.2 to 16 Gy. At five weeks post-irradiation, the tumor surface area posttreatment/ pre-treatment ratio was 12.2 ± 6.6 for Sham, 7.8 ± 4.1 for Beam only, 4.4 ± 5.6 for BPA-BNCT I, and 0.45 ± 0.20 for BPA-BNCT II; tumor nodule weight was 750 ±
480 mg for Sham, 960 ± 620 mg for Beam only, 380 ± 720 mg for BPA-BNCT I and 7.3 ± 5.9 mg for BPA-BNCT II. The BPA-BNCT II group exhibited statistically significant tumor control with no contributory liver toxicity. Potential threshold doses for tumor response and significant tumor control were established at 6.1 Gy and 9.2 Gy respectively.
Radiation and Environmental Biophysics 2013 en prensa

 

PSICOLOGIA Y RELACIONES HUMANAS

    1).- PROYECTO MOVILIDAD SUSTENTABLE: PREFERENCIAS IMPLÍCITAS Y EXPLÍCITAS POR DIFERENTES MODOS DE TRANSPORTE
    Directora: Dra Alba Mustaca. Mail albamustaca@gmail.com (inicio 2013, finalización 2015)


A) Percepción de los beneficios individuales del uso de la bicicleta compartida como modo de transporte
Adriana Jakovcevica,∗, Paul Francoa, Marcela Visona Dalla Pozzaay Rubén Ledesma
Resumen
El uso de la bicicleta como modo de transporte se asocia con numerosos beneficios ambien-tales y sociales, no obstante, se desconoce cuáles son los más valorados por los ciclistas.El objetivo de este estudio fue conocer en qué medida el Sistema de Transporte Público deBicicletas (STPB) de la ciudad de Buenos Aires produjo impactos positivos sobre los aspectosque las personas valoran en el momento de viajar, analizando si estas evaluaciones varíanen función de la intensidad de uso del STPB. Para ello, se dise˜nó un cuestionario basado enun estudio sobre la calidad de vida residencial que fue aplicado a 161 usuarios del STPB.Los resultados indicaron que los aspectos del viajar: rapidez, control del horario de llegada,ahorro de dinero y en menor medida la salud, fueron muy importantes para los usuarios yfueron los que más mejoraron a partir del uso del STPB. Asimismo, las personas que usan elsistema con mayor intensidad son las que perciben más beneficios sobre los aspectos no ins-trumentales del viajar como el entretenimiento y la comodidad. Estos resultados sugierenque para lograr que las personas realicen un cambio sustentable en sus comportamientosde movilidad es necesario mantener las ventajas instrumentales que ofrece el servicio debicicletas compartidas sobre los otros medios de transporte.© 2015 Fundación Universitaria Konrad Lorenz. Publicado por Elsevier España, S.L.U. Estees un artículo Open Access bajo la licencia CC BY-NC-ND

Abstract: Cycling as a mode of transport is associated with numerous social and environmental bene-fits. However, the benefits that are most valued by cyclists are unknown. This study soughtto find out to what extent the Public Bike Sharing System (PBSS) of the city of Buenos Airesproduced positive impacts on aspects that users value most when traveling, and analysingwhether these evaluations vary according to the intensity of use of the PBSS. To achieve this∗xxxaim, a questionnaire was designed based on a study on residential quality of life, whichwas administered to 161 PBSS users. Results indicated that travel aspects such as rapidity,control of arrival time, saving money and –to a lesser extent– health were very importantto users, and these aspects had the greatest improvement since they started to use thePBSS. Similarly, those who used the system with greater intensity perceived greater non-instrumental benefits, such as entertainment and comfort. These results suggest that, inorder to achieve a sustainable change in mobility behaviours, it is necessary to maintain theinstrumental advantages of bike sharing over other modes of transport.© 2015 Fundación Universitaria Konrad Lorenz. Published by Elsevier España, S.L.U.This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

B) Determinantes Psicológicos de las Conductas de Movilidad: Un Estudio de Revisión
Adriana Jakovcevic, Paul Franco, Romina Caballero, Rubén Ledesma
Resumen
Una alternativa para reducir las consecuencias nocivas del uso del automóvil es la elección del transporte público (TP). Ello requiere cambios en la infraestructura y en el comportamiento de las  personas. Por este motivo, es necesario conocer qué motivaciones determinan la elección de cada medio de transporte. El objetivo de este estudio fue analizar qué factores psicológicos explican la elección del automóvil y del TP. Se efectuó una revisión sistemática de la literatura de los últimos 11 años, obteniendo 21 artículos. Los resultados indicaron que los procesos intencionales, serían los que mejor explican la conducta de usar el automóvil y el TP. Aunque en ocasiones su poder explicativo se incrementa al incluir en el modelo a los procesos automáticos y normativos. No obstante, el hábito sería más importante en la elección del automóvil que en la del TP. Se discuten los resultados hallados y se ofrecen lineamientos para investigaciones futuras.
An alternative to reduce the harmful consequences of car use is the choice of public transport (PT). This requires infrastructural as well as behavioural changes. For this reason, it is necessary to know which motivations determine the choice of each transport mode. The aim of this study was to analyze which are the psychological factors that better explain car use and PT use. A systematic review of the literature of the past 11 years was performed, obtaining 21 datasets. Results indicated that intentional processes are the more suitable to explain the choice of car and PT. Although its explanatory power usually increases when automatic and normative processes are included in the model. However, the automatic processes would be more important for car use than for PT use. Results are discussed and guidelines for future research are offered.

C) Charges for plastic bags: Motivational and behavioral effects
Adriana Jakovcevic, Linda Steg , Nadia Mazzeo , Romina Caballero , Paul Franco , Natalia Putrino  & Jesica Favar
Journal of Environmental Psychology DOI: 10.1016/j.jenvp.2014.09.004Accepted Date: 20 September 2014
Two field studies tested the effects of a charge for single-use plastic bags recently implemented in Buenos Aires City, Argentina. Study 1 showed a greater increase in consumers’ own bag use after the charge was introduced in supermarkets where the policy was introduced, in comparison to control supermarkets where the charge was not
introduced, or was introduced later in time. The effects were even stronger two months later. Study 2 analyzed factors underlying policy support and own bag use six month after the charge was introduced. Policy supporters highlighted environmental benefits of the charge, while opponents stressed the financial costs. Moreover, most consumers indicated that they carried their own bags to protect the environment, suggesting that intrinsic rather than extrinsic motivations caused behavioral changes. The theoretical and practical implications of the findings are discussed.

D) Uso de la Bicicleta como Medio de Transporte: Influencia de los Factores Psicológicos. Una Revision de la Literatura
Romina Caballero, Paul Franco, Alba Mustaca, Adriana Jakovcevic
Psico  v. 45, n. 3, pp. 316-324, jul.-set. 2014
El uso masivo de transportes sustentables como la bicicleta, no sólo requieren cambios en la infraestructura de las ciudades sino un cambio en el comportamiento. En función de ello, resulta necesario conocer cuáles son las motivaciones que determinan la elección de este medio de transporte. El objetivo del trabajo fue analizar cuáles son las variables psicológicas que mejor predicen el uso de la bicicleta como modo de transporte, mediante una revisión sistemática de la literatura de los últimos 10 años. Los resultados de nuestro análisis indicaron que la elección de la bicicleta como medio de transporte se encuentra determinada por procesos intencionales. La intención de usar este medio principalmente se asocia a la percepción de apoyo social así como a la percepción de las propias habilidades para ejecutar la conducta (autoeficacia) y en menor medida, a una actitud positiva hacia la misma. No obstante, una vez que trasladarse en bicicleta se ha convertido en una conducta habitual, la influencia de los procesos racionales se debilita. Esto sugiere que en el diseño de políticas destinadas a incrementar la movilidad sustentable se deben contemplar estrategias diferenciadas de acuerdo a la frecuencia de uso de este modo de transporte.

 

2).- PROYECTO: ASPECTOS COMPORTAMENTALES Y GENÉTICOS DE LA FRUSTRACIÓN.
Director Giselle Kamentzky mail: yoselevich@yahoo.com.ar

A) Efecto del Haloperidol sobre el Contraste Sucesivo Positivo Consumatorio en Ratas Adultas con Aislamiento Adolescente
Lucas Cuenya, Matías Serafini, Alba Mustaca, Giselle Kamenetzky
Resumen
Las ratas expuestas a aislamiento adolescente (AA) muestran alteraciones neurológicas y conductuales en la adultez, muchas de ellas relacionadas con cambios en la respuesta ante reforzadores apetitivos. En estudios previos las ratas con AA mostraron un incremento del Contraste Sucesivo Positivo consumatorio (CSPc, i.e, mayor consumo de una solución azucarada al 32%, 24 hs después de tener acceso a una solución al 4%), respecto de animales sin AA. El objetivo de este estudio fue evaluar si este efecto está asociado a la hiperactividad dopaminérgica. Se administró haloperidol a animales con AA (0.1 mg/kg, i.p.) antes de los ensayos de incremento del refuerzo y salina a un grupo control. No se halló CSPc en los animales que recibieron haloperidol, mientras que en los sujetos con salina se observó en un ensayo. Si bien los resultados apoyan la hipótesis propuesta, es necesario realizar futuros experimentos para determinar con mayor precisión el correlato neuroquímico del incremento de CSPc en animales con AA.
Rats exposed to adolescent isolation (AA) show neurological and behavioral disorders into adulthood, many of them related to changes in response to appetitive reinforcers. Previous studies showed an increase of consummatory Successive Positive Contrast (cSPC, i.e., increased consumption of 32% sugar solution, 24 hours after having access to 4% solution) in rats exposed to AA, in comparison to animals without AA. This study aim at evaluating whether this effect is associated with dopaminergic hyperactivity. Haloperidol (0.1 mg / kg, i.p.) was administered before animals with AA were exposed to the presentation of the increased solution (4% to 32%), while saline was administered to the control group. cSPC effect was not observed in animals receiving haloperidol, while a one trial positive contrast was expressed in animals receiving saline. These results confirm the proposed hypothesis. Although the results are promising, further experiments are needed to determine more precisely the neurochemical correlate of increased cSPC in animals with AA.

B) Change in the hedonic value of an aversive stimulus in the presence of a pre-exposed odor.
Kamenetzky GV1, Suárez AB2, Pautassi RM3, Mustaca AE2, Nizhnikov ME4.
Physiol Behav. 2015 Sep 1;148:51-7. doi: 10.1016/j.physbeh.2014.12.041. Epub 2014 Dec 24.

Abstract
Rats exhibit a sensitive period from the time of birth until postnatal day 10 during which they develop preferences for odors even if those odors are paired with a moderately aversive stimulus. It is still unknown whether pre-exposure to an odor produces alterations on intake responses of basic tastants, and on other patterns that indicate a change in the hedonic value of reward, such as nipple grasping behavior. The current study assessed the effect of pre-exposure to an odor immediately after birth on intake responses of appetitive and aversive tastants. The objectives were to assess if 3-hour-old rats adjust their behaviors to obtain different values of appetitive and aversive rewards in the presence of a familiar odor. Specifically we wanted to determine whether the intake of saccharin or quinine, administered through the artificial nipple, increases in the presence of the familiar odor. Results showed that 3-hour-old rats differentially respond to two different concentrations of saccharin and two concentrations of quinine. In the presence of the pre-exposed odor newborn rats increased intake and grasp responses to the artificial nipple containing quinine. This effect disappeared with a higher concentration of quinine. These results suggest that the pre-exposed odor generated a change in the hedonic value of the aversive reward.

C) Early Experiences and Incentive Relativity
International Journal of Comparative Psychology, 27(3) 2014
Cuenya, Lucas, Kamenetzky, Giselle, Mustaca, Alba Elisabeth,

Abstract:
Human and animal studies have shown the long-lasting impact of early life experiences on the development of individual differences in stress responsiveness in later life. Despite the numerous works that evaluate the effect of early experiences on different behavioral paradigms, which for the most part are related to aversive situations, there are few studies that assess the effects on the unexpected downshift or omission of positive rewards. The purpose of this article is to present several independent lines of research into how frustration responses during adulthood may be influenced by early experiences. Very few works have been found on the subject, and in most cases the results were negative or controversial. However, more recent investigations suggest that the responses in adults to frustration or euphoria may be modulated by early experiences.

D) Postweaning isolation affects responses to incentive contrast in adulthood
Lucas Cuenya, Alba Mustaca & Giselle Kamenetzky
Developmental Psychobiology (2014)
Adolescence is a time involving a series of changes in the use of appetitive reinforcers like food, as well as neuroendocrine changes like those taking place in the mesolimbic dopamine function. Social isolation from postnatal day 21 to 36 in rats leads to behavioral and neurophysiological alterations such as increased consumption of appetitive  reinforcers. The work is focused on studying how exposure to chronic stress induced by social isolation during adolescence can have a long-lasting effect on responses reinforcement shifts in adulthood. Two experiments were performed in rats in order to analyze the effect of adolescent isolation on the responses to unanticipated shifts in
reinforcement during adulthood, in reinforcement devaluation (32% to 4% of sucrose solution), increase (4% to 32% of sucrose solution) and extinction (32% to 0% of sucrose solution) procedures. Adolescent isolation intensified the intake response resulting from a  reinforcement increase (i.e., greater positive contrast), but had no effect on the response to  reinforcement devaluation and omission. The implications of this procedure are discussed, along with the underlying behavioral and neurochemical mechanisms.

E) Ontogeny of Consummatory Successive Negative Contrast in Rats
Andrea B. Suarez,  Alba E. Mustaca,  Ricardo M. Pautassi2, Giselle V. Kamenetzky
Developmental Psychobiology, DOI 10.1002/dev.21178 _ _ 2013 Wiley Periodicals, Inc.
Consummatory successive negative contrast (cSNC) occurs when organisms repeatedly exposed to a high-magnitude reward are suddenly given a low-magnitude reward. This results in a significant reduction in the consumption of the devalued reinforcer, at a level even below that of a group which had been always exposed to the low-magnitude reinforcer. A scarcity of animal studies assessed the expression of this phenomenon during early development. Three experiments assessed age of cSNC onset in preweanling rats. Percent body weight gained (%BWG) and taste reactions associated with reinforcement devaluation were measured. A reduction in %BWG and a significant increase in emission of aversive hedonic behaviors, indicative of cSNC, occurred on postnatal day 18 (PD 18; Experiments 1 and 2), but not on PD 14 or PD 17 (Experiments 3a and 3b). The neurobiological mechanisms underlying these effects and theoretical implications are discussed. _ 2013 Wiley Periodicals, Inc. Dev Psychobiol

F) Change in the hedonic value of an aversive stimulus in the presence of a
pre-exposed odor
Giselle V. Kamenetzky , Andrea B. Suárez , Ricardo M. Pautassi , Alba E. Mustaca , Michael E. Nizhnikov
Physiology & Behavior xxx (2014) xxx–xxx
Rats exhibit a sensitive period from the time of birth until postnatal day 10 during which they develop preferences for odors even if those odors are paired with a moderately aversive stimulus. It is still unknown whether pre-exposure to an odor produces alterations on intake responses of basic tastants, and on other patterns that indicate a change in the hedonic value of reward, such as nipple grasping behavior. The current study assessed the effect of pre-exposure to an odor immediately after birth on intake responses of appetitive and aversive tastants. The objectiveswere to assess if 3-hour-old rats adjust their behaviors to obtain different values of appetitive and aversive rewards in the presence of a familiar odor. Specifically we wanted to determine whether the intake of saccharin or quinine, administered through the artificial nipple, increases in the presence of the familiar odor. Results showed that 3-hour-old rats differentially respond to two different concentrations of saccharin and two concentrations of quinine. In the presence of the pre-exposed odor newborn rats increased intake and grasp responses to the artificial nipple containing quinine. This effect disappearedwith a higher concentration of quinine. These results suggest that the pre-exposed odor generated a change in the hedonic value of the aversive reward.

 

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