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En este trabajo se presentan los resultados de los estudios realizados sobre un tramo de cadena, compuesto por dos segmentos, de cuatro y tres eslabones respectivamente, unidos por un grillete en forma de U, que se cierra por intermedio de un perno transversal. Los eslabones, a juzgar por las marcas observadas, tenían originalmente contretes en su parte media; sin embargo no todos lo conservan. El tramo, hallado fuera de contexto, fue entregado para su estudio por el Director de Cultura de San Pedro a Mariano Ramos en abril de 2012. El objetivo planteado fue precisar el origen de la cadena y su probable relación con los acontecimientos de la batalla de Vuelta de Obligado. Para ello se analizaron fuentes documentales y se recurrió a métodos de caracterización de materiales que incluyeron estudio dimensional, radiografía y metalografía.

Introduction: people with clinical characteristics of MODY benefit with a correct genetic diagnosis and are often only studied if having family history. In this work there were studied four people selected per their clinical characteristics of genitourinary abnormalities and MODY Diabetes, using the worldwide inclusion criteria for MODY5 except for a family history of diabetes or kidney disease. Methods: gene mutation screening in four people with clinical characteristics of MODY5 in search for alterations in the HNF1B gene with Sanger or NGS sequencing, and bioinformatic tools to analyze the results of the sequences. Results: from four people studied we found three mutations in the HNF1B gene, including a missense mutation previously described and two de novo whole gene deletions. The other person did not present any alteration in that gene even having clinical characteristics. Conclusions: people with clinical characteristics of MODY and having pancreatic, renal, kidney or genital located abnormalities are candidates for genetic screening of HNF1B. Yet, genetic screening of HNF1B should not only be restricted to such people but should also be considered in people without diabetes but having those other characteristics. We suggest also, the study of people even in the absence of family history, given that the possibility of occurrence of de novo mutations is underestimated.

Background: Given the increasing evidence supporting the association between telomere shortening and diabetes, the aim of the present work was to establish whether MODY patients suffer a reduction in telomere lenght (TL) due to oxidative stress produced by chronic hyperglycemia, despite not presenting insulin resistance or inflammation. Methods: We analysed clinical and biochemical parameters in 35 MODY2 and 12 MODY3 patients compared with 48 control subjects. The absolute telomere length (aTL) of peripheral blood leukocytes was measured using the quantitative polymerase chain reaction (qPCR). Results: A significant negative correlation was observed between aTL and age in the whole population, among MODY patients and in each subtype studied, MODY2 and MODY3, which allowed us to validate the method. We found, for the first time, that MODY patients have shorter aTL with respect to non-diabetic controls (6.49 ± 3.31 kbp vs 11.13 ± 7.82 kbp, p =.006). However, no differences were found between MODY2 and MODY3. In addition, aTL showed a negative correlation with duration of the disease and fasting plasma glucose (FPG) levels in MODY patients in general and also with HbA1c in MODY2 patients in particular. Conclusions: Both MODY2 and MODY3 types present telomere shortening, which, at least partly, responds to HbA1c and FPG levels. These findings suggest comparable mechanisms underlying the attrition of TL. Taken together, our results on aTL in MODY patients may provide a parameter relatively easy and inexpensive to quantify in order to measure the impact of high glucose levels and potentially carry out antidiabetic treatment with stricter targets. Fil: Millán, Andrea Liliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Genética y Biología Molecular; Argentina Fil: Trobo, Sofía I.. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Genética y Biología Molecular; Argentina Fil: de Dios, Alejandro. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentina Fil: Cerrato García, Martina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Genética y Biología Molecular; Argentina Fil: Pérez, María S.. No especifíca; Fil: Cerrone, Gloria Edith. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Genética y Biología Molecular; Argentina Fil: Frechtel, Gustavo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Genética y Biología Molecular; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentina Fil: Lopez, Ariel Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Inmunología, Genética y Metabolismo. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Inmunología, Genética y Metabolismo; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Departamento de Microbiología, Inmunología y Biotecnología. Cátedra de Genética y Biología Molecular; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Hospital de Clínicas General San Martín; Argentina

Introducción: la hiperglucemia es uno de los más importantes factores que determinan la producción de estrés oxidativo e inflamación, procesos que pueden acelerar el acortamiento de los telómeros.Objetivos: analizar la longitud telomérica absoluta (LTa) en individuos con niveles de glucosa en ayunas alterada (GAA) en comparación con individuos que presentan niveles normales de glucosa (GAN). Estudiar a partir de un estudio prospectivo controlado, la variación en la LTa en pacientes con DM2 descompensada antes y después del tratamiento.Materiales y métodos: se estudió una población de 246 individuos de ambos sexos, conformada por individuos con obesidad, individuos con DM2 o MODY e individuos controles sanos. Se dividieron en individuos con niveles de glucemia =110 mg/dl y 50Y). Se estudió un subgrupo de 30 pacientes con DM2 de reciente diagnóstico, al inicio (T0) y a los 6 meses (T6) de un tratamiento farmacológico y medidas higiénico-dietéticas, con el objetivo de lograr la compensación metabólica. En ambos estudios se determinaron las variables bioquímico-clínicas de todos los individuos y la LTa por PCR cuantitativa en tiempo real. Los análisis estadísticos se realizaron utilizando el software GraphPad Prism y SPSS.

The Metabolic Syndrome (MetS) is a cluster of cardiometabolic risk factors, usually accompanied by the presence of insulin resistance (IR) and a systemic subclinical inflammation state. Metabolically healthy obese (MHO) individuals seem to be protected against cardiometabolic complications. The aim of this work was to characterize phenotypically the low-grade inflammation and the IR in MHO individuals in comparison to obese individuals with MetS and control non obese. We studied two different populations: 940 individuals from the general population of Buenos Aires and 518 individuals from the general population of Venado Tuerto; grouped in three groups: metabolically healthy non-obese individuals (MHNO), MHO and obese individuals with MetS (MSO). Inflammation was measured by the levels of hs-CRP (high-sensitivity C reactive protein), and we found that MHO presented an increase in inflammation when compared with MHNO (Buenos Aires: p

Background Maturity-onset diabetes of the young 2 (MODY2) is a form of diabetes that is clinically characterized by early age at onset and mild hyperglycemia, and has a low risk of late complications. It is often underdiagnosed due to its mild symptoms. To date, over 600 different GCK /MODY2 mutations have been reported. Despite only a few de novo mutations having been described, recent studies have reported the detection of a higher frequency of this kind of mutation. Therefore, de novo mutations could be more frequent than previously described. Even though common recommendations regarding the diagnosis of monogenic diabetes include the existence of a strong family history of diabetes, here we describe the study of mutations in two families with a symptomatic individual with clear clinical features of MODY2 but without any family history of diabetes. Methods Genetic diagnosis in a group of participants with MODY2 characteristics was carried out by direct sequencing of coding regions of the GCK gene and analysis of mutations found using bioinformatics tools. Results We found two de novo mutations, one of them novel, constituting 14.29% of all the participants who were phenotyped as MODY2. Conclusions The number of mutations in GCK /MODY2 or even other MODY-related genes is undoubtedly underestimated, as accepted criteria for performing genetic tests include family history of the pathology. These cases illustrate the value of analyzing the GCK gene in patients with clinical features of MODY2, even in the absence of family history of the condition as it is essential for establishing the correct treatment.

Introduction There are at least six subtypes of Maturity Onset Diabetes of the Young (MODY) with distinctive genetic causes. MODY 3 is caused by mutations in HNF1A gene, an insulin transcription factor, so mutations in this gene are associated with impaired insulin secretion. MODY 3 prevalence differs according to the population analyzed, but it is one of the most frequent subtypes. Therefore, our aims in this work were to find mutations present in the HNF1A gene and provide information on their prevalence. Material and methods Mutations screening was done in a group of 80 unrelated patients (average age 17.1 years) selected by clinical characterization of MODY, by SSCP electrophoresis followed by sequenciation. Results We found eight mutations, of which six were novel and four sequence variants, which were all novel. Therefore the prevalence of MODY 3 in this group was 10%. Compared clinical data between the non-MODY 3 patients and the MODY 3 diagnosed patients did not show any significant difference. Discussion Eight patients were diagnosed as MODY 3 and new data about the prevalence of that subtype is provided. Our results contribute to reveal novel mutations, providing new data about the prevalence of that subtype.

INTRODUCTION: Mutations in the glucokinase gene (GCK) produce a subtype of Maturity onset diabetes in the young (MODY), named MODY 2. To date over than 190 different mutations have been identified, distributed over the coding regions and the exon-intron boundaries of the gene. The aim of this work was to study the nature and frequency of mutations in the GCK gene, in a MODY clinically characterized Argentinean population. MATERIAL AND METHODS: Seventy unrelated individuals were selected based on MODY clinical features. The study methodology consisted in PCR amplification of the coding regions of the GCK gene, SSCP electrophoresis analysis of the amplified fragments and direct sequencing of the fragments with abnormal electrophoresis pattern. RESULTS: We identified a total of six patients with mutations in the GCK gene. This included two novel mutations: g.1831C>A, g.3792T>A, one already reported by our group, g.168fsdelC (same mutation in two non-related patients) and two already reported: p.Gln138Pro and p.Gly261Glu. With that data, we could establish the prevalence of MODY 2 among the patients in study reaching to 8.6%. DISCUSSION: The main contribution of this study is to inform about two novel mutations not described to date and to make an approach to the establishment of the prevalence of MODY 2 in the population under study. These findings contribute to confirm the allelic heterogeneity of GCK gene mutations and may provide an insight into the structure-function relationship of the GCK.

Autoimmune diabetes is an organ specific and multifactorial disorder with a classical onset as insulin dependent diabetes mellitus (IDDM) and with another form of onset as latent autoimmune diabetes in adults (LADA), which has a slower onset and a later progress to insulin dependency as a result of the beta cells destruction. The cytotoxic T lymphocyte-antigen 4 (CTLA4) has been identified as a susceptible marker of the disease; it is considered a down regulator of T cell function, playing a key role in autoimmunity. We analyzed CTLA4 codon 49 A/G polymorphism in 123 IDDM patients, 63 LADA patients and 168 healthy non-diabetic control individuals. The frequency of the heterozygous A/G genotype in LADA patients was significantly increased compared to IDDM patients (55.6 vs. 39.8%, p = 0.0415). There was no statistical significant difference in the distribution of the A/G dimorphism between autoimmune diabetes patients (LADA or IDDM) and non-diabetic control individuals. HLA DQ region is responsible for the genetic susceptibility to autoimmune diabetes in IDDM patients in about 50% and it has a lower effect in genetic susceptibility in LADA patients. Several other genetic loci are needed to develop autoimmune diabetes in adult patients. Therefore, LADA may be the result of a combined minor risk loci effect in a major risk haplotype.

Background: The different clinical presentations of latent autoimmune diabetes in adults (LADA) and type 1 diabetes mellitus may be the result of susceptibility genes in determining the mode of onset. We analyzed the 5′ polymorphisms of the insulin mini-satellite region (INS), a variable number of tandem repeats (VNTR) [repeat units; RU]. We evaluated the association of the different INS-VNTR alleles in patient susceptibility to LADA autoimmune diabetes. To our knowledge, this constitutes the first study of this kind performed in a Caucasian population. Methods: From an group of 160 Argentinean patients previously characterized as having LADA, we selected 44 patients who presented with humoral autoimmunity for genotyping and compared them to 88 patients with type 1 diabetes and 138 healthy individuals. The INS-VNTR allele classes were determined by Southern blotting (class I: 21–44RU; class III: 138–159RU). Subjects with class I alleles were further studied using PCR amplification to determine the exact length of the alleles (short 1S: 22–37RU; medium 1M: 38–41RU; large 1L: 42–43RU). Allelic and genotype frequencies were estimated by χ2 tests for independence with 2 × 2 contingency tables and the relative risks (RR) were determined using GraphPad InStat software. Results: We observed differential associations among the class I alleles when comparing patients with LADA (80.6%) and type 1 diabetes (81.3%) with the controls (70%; p < 0.005). This increase was largely due to the high frequency of the 1S/S genotype (63.6% LADA vs 37% controls, with a p-value of 0.0019 [p1]; 53.4% type 1 diabetes vs 37% controls, with a p-value of 0.0149 [p2]). Remarkably, all LADA patients genotyped as class I homozygous had the shorter (S) class I allele (100%). Differences in the overall 1S distribution were observed: in LADA the 94.4% of the alleles were equal to or smaller than 35RU, while in patients with type 1 diabetes it was 78.3% and in controls 74.1%. Moreover, the relative risks associated with the 1S/S genotype for patients with LADA showed a substantial increase with respect to those with type 1 diabetes (52%) when we compare them to the controls (1S/S LADA/control, 2.282 [RR1] vs type 1 diabetes/control, 1.497 [RR2]). Conclusion: The presence of the 1S allele could be considered a risk factor in LADA patients, as previously reported for type 1 diabetes. The class I INS-VNTR allele in LADA increases genetic susceptibility to disease development., Centro de Endocrinología Experimental y Aplicada

Maturity onset diabetes of the young (MODY) is caused by mutations in at least six different genes, including the glucokinase gene (MODY 2) and genes encoding the tissue-specific transcription factors (MODY 1 and MODY 3-6). To determine the presence of mutations in MODY 2 in four members of a family who have the clinical characteristics of MODY, we performed polymerase chain reaction and single strand conformation polymorphism screening, followed by DNA sequencing. We found a novel mutation which consisted of the deletion of a cytosine in the position 2 of the exon 5 codon 168. This mutation produced a frame shift which determines a stop codon at position 203 in exon 6. The identification of a mutation in glucokinase gene and transcription factor genes in patients with early-onset diabetes confirms the diagnosis of MODY and has important implications for clinical management.

El término MODY (Maturity Onset Diabetes in Youngs) proviene de la antigua clasificación de la DM que la subdividía en aquellas que comenzaban en la juventud de las que lo hacían en la edad adulta. En la actualidad, se las encuadra dentro de aquellos cuadros caracterizados por “defectos genéticos en la función de la célula beta”. Es una forma monogénica de la enfermedad cuyo denominador común es la hiposecreción de insulina como factor desencadenante primario. Actualmente se han identificado 13 subtipos de MODY. Si bien MODY representa aproximadamente el 1-2% de los pacientes con DM, se estima que un gran porcentaje de los casos se encuentra sin diagnosticar. En cuanto a la frecuencia relativa, MODY 2 y MODY 3 representan alrededor del 60-80% de los casos, y MODY 1 el 10% de los mismos. En general, los pacientes con MODY se caracterizan por tener: 1) DM de comienzo en la edad joven, en general menores de 25 años; 2) fuerte influencia familiar; 3) sin estigmas de insulinorresistencia; 4) insulinoindependencia; 5) ausencia de autoanticuerpos relacionados con DM autoinmune. El diagnóstico de MODY trae aparejada implicancias pronósticas, terapéuticas y sobre consejo genético. Aquellos pacientes con mutación en glucoquinasa (MODY 2) habitualmente no desarrollan complicaciones crónicas tanto micro como macrovasculares y en general no requieren tratamiento farmacológico, mientras que aquellos con mutaciones en HNF-1α (MODY 3) tienen tendencia a complicaciones microvasculares y poseen la característica de presentar hiperrespuesta a dosis bajas de sulfonilureas, incluso en algunas ocasiones presentan hipoglucemias severas.