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Oligosaccharides are gaining importance because of their beneficial properties in human health. They normally appear in natural and synthetic products as complex mixtures of different monomeric units, glycosidic linkages and degrees of polymerization, being disaccharides and trisaccharides usually the most abundant ones. Although liquid chromatography-mass spectrometry is a useful technique for oligosaccharides analysis, the similarity of their structures makes difficult their characterization. Moreover, there is still scarce information about the relationship between carbohydrate chemical structure, mass spectra and chromatographic data. Then, in this work, chromatographic parameters for 23 disaccharides with different linkages and monomeric units (glucose, galactose, mannose and fructose) were determined using porous graphitized and hydrophilic interaction liquid chromatography columns. Moreover, diagnostic ions of these disaccharides obtained by tandem mass spectra (MS2) were established by stepwise linear discriminant analysis. The relationship between carbohydrate chemical structure and their chromatographic retention data and characteristic ions obtained by multiple-stage mass spectrometry (MSn) was successful in establishing some specific criteria that allowed the characterization of trisaccharides with different structural features.

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Myotonic dystrophy type 1 is caused by expansion of a CTG trinucleotide repeat situated in the DMPK gene. Worldwide genetic studies suggest a single or limited number of mutational events cause the disease. However, distribution of CTG alleles and disease incidence varies among ethnicities. Due to the great ethnic diversity of the Mexican population, the present study was aimed at analyzing the impact of different lineages in shaping the CTG-repeat allelic distribution in the contemporary Mexican-Mestizo population as well as to shed light on the DM1 ancestral origin. Distribution of CTG-repeat alleles was similar among Mestizo and Amerindian subpopulations with (CTG)11-13 being the most frequent alleles in both groups, which implies that Mexican-Mestizo allelic distribution has been modeled by Amerindian ancestry. We diagnosed a relatively high number of cases, consistent with the high frequency of large-normal alleles found in Mexican subpopulations. Haplotype analysis using various polymorphic-markers in proximity to DMPK gene indicates that a single founder mutation originates myotonic dystrophy type 1 in Mexico; however, Y-STR haplogroups data and the presence of pre-mutated and large normal alleles in Amerindians support the hypothesis that both European and Amerindian ancestral chromosomes might have introduced the disease to the Mexican population, which was further disseminated through mestizaje.

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Chrysactinia mexicana A. Gray (Asteraceae) and Turnera diffusa Willd (Turneraceae) are employed in traditional medicine as aphrodisiacs; however, there is no scientific evidence supporting the prosexual properties of C. mexicana. The aim of this study was to determine whether an aqueous extract of C. mexicana (Cm) stimulates rat male sexual behavior in the sexual exhaustion paradigm. Sexually exhausted (SExh) male rats were treated with Cm (80, 160, and 320 mg/kg), an aqueous extract of T. diffusa (Td), or yohimbine. The sexual exhaustion state in the control group was characterized by a low percentage of males exhibiting mounts, intromissions, and ejaculations and no males demonstrating mating behavior after ejaculation. Cm (320 mg/kg), Td, or yohimbine significantly increased the proportion of SExh rats that ejaculated and resumed copulation after ejaculation. In males that exhibited reversal of sexual exhaustion, Cm (320 mg/kg) improved sexual performance by reducing the number of intromissions and shrinking ejaculation latency. The effects of treatments on sexual behavior were not related with alterations in general locomotion. In conclusion, the prosexual effects of Cm, as well as those of Td, are established at a central level, which supports the traditional use of C. mexicana for stimulating sexual activity.

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Los perfiles profesionales de los egresados en área de la salud, y en particular de enfermería, requieren ajustarse a la compleja interacción que demandan las necesidades sociales y las exigencias del mercado laboral. Esto crea la necesidad de identificar fortalezas y debilidades durante su formación profesional a través de la sistematización de estudios de egresados, los cuales orientan a la mejora continua de los programas educativos, para facilitar la incorporación y desarrollo de los(as) egresados(as) en el ámbito laboral. Objetivo Describir la opinión de los egresados de enfermería de la Universidad Autónoma de Tlaxcala sobre la congruencia de los contenidos curriculares y requerimientos laborales al ofrecer el cuidado profesional. Material y métodos Estudio descriptivo, transversal. Incluyó 84 egresados de 3 generaciones, seleccionados por muestreo simple aleatorio. Se empleó un cuestionario adecuado y estructurado con base en la propuesta de la Asociación Nacional de Universidades e Instituciones de Educación Superior de 1998, organizado en 6 apartados. Resultados El 87% opinan que los contenidos curriculares son congruentes con las actividades que realizan al ofrecer el cuidado, el 86% perciben satisfacción de sus conocimientos, el 85% se consideran bien aceptados laboralmente, el 95% aprecian relevante su desempeño laboral, el 66% son contratados en 2.° y 3.er nivel de atención en el sector salud. Conclusiones Los egresados consideran que existe congruencia entre los contenidos curriculares con el desempeño profesional; se ubican mayormente en áreas asistenciales del 2.° y 3.er nivel de atención, y perciben satisfacción de los conocimientos adquiridos y aceptación laboral.

Professional profiles of graduates from the health areas, and particularly those from nursing, require adjustments in order to meet the complex interactions which social needs and labor market characteristics demand. This situation creates the need to identify strengths and weaknesses in the formation of these graduates. By systematizing and continuously improving their studies, a successful incorporation and development into the complex labor markets is more likely to be achieved. Objective To describe the opinion which the nursing graduates from the Tlaxcala Autonomous University have on the congruency of the curricular contents and the working requirements while providing professional care. Materials and methods Descriptive and transversal study which included 84 graduates from 3 generations who were selected by random simple sampling, and which used a structured and convenient questionnaire following the 1998 ANUIES proposal organized in 6 dominions. Results 87% of the participants opined the curricular contents are congruent with the activities they do while providing care; 86% perceive satisfaction with their knowledge; 85% consider they are well fit regarding labor; 95% consider their working performance relevant; 66% are hired into the Health Sector's 2nd and 3rd levels of attention. Conclusions There is congruency between the curricular contents and their professional performance; the graduates are mainly located within the assisting areas of the 2nd and 3rd levels of attention; they feel satisfied with their knowledge and perceive labor acceptance.

Os perfis profissionais dos egressos da área de saúde, e no particular da enfermagem, requerem se ajustar à complexa interação que demandam as necessidades sociais e as exigências do mercado de trabalho, isto cria a necessidade de identificar fortalezas e as fraquezas durante sua formação profissional, a través da sistematização de estudos de egressos, os quais dirigem a melhora contínua dos programas educativos, para facilitar a incorporação e desenvolvimento dos egressos no contexto de trabalho. Objetivo Descrever a opinião dos egressos de Enfermagem da Universidade Autônoma de Tlaxcala sobre a congruência dos conteúdos curriculares e requerimentos de trabalho ao oferecer o cuidado profissional. Material e métodos Estudo descritivo, transversal, incluiu 84 egressos de 3 gerações, escolhidos pela amostra simples aleatória, empregando um questionário adequado e estruturado com base na proposta da ANUIES de 1998 em 6 secções. Resultados 87% acharam que os conteúdos curriculares são congruentes com as atividades que realizam ao oferecer o cuidado, 86% percebe satisfação de seus conhecimentos, 85% se considera bem aceito no trabalho, 95% percebe relevante seu desempenho no trabalho, 66% são contratados em segundo e terceiro nível de atenção no setor de saúde. Conclusões Existe congruência entre os conteúdos curriculares com o desempenho profissional; os egressos situam-se principalmente nas áreas assistenciais do segundo e terceiro nível de atenção, percebem satisfação dos conhecimentos adquiridos e aceitação no trabalho.

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Spinocerebellar ataxia type 7 (SCA7) is an inherited neurodegenerative disorder characterized by progressive cerebellar ataxia associated with macular degeneration. We recently described one of the largest series of patients with SCA7 that originated from a founder effect in a Mexican population, which allowed us to perform herein the first comprehensive clinical, neurophysiological, and genetic characterization of Mexican patients with SCA7. In this study, 50 patients, categorized into adult or early phenotype, were clinically assessed using standard neurological exams and genotyped using fluorescent PCR and capillary electrophoresis. Patients with SCA7 exhibited the classical phenotype of the disease characterized by cerebellar ataxia and visual loss; however, we reported, for the first time, frontal-executive disorders and altered sensory-motor peripheral neuropathy in these patients. Semiquantitative analysis of ataxia-associated symptoms was performed using Scale for the Assessment and Rating of Ataxia (SARA) and the Brief Ataxia Rating Scale (BARS) scores, while extracerebellar features were measured employing the Inventory of Non-ataxia Symptoms (INAS) scale. Ataxia rating scales confirmed the critical role size of cytosine-adenine-guanine (CAG) repeat size on age at onset and disease severity, while analysis of CAG repeat instability showed that paternal rather than maternal transmission led to greater instability.

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Myotonic dystrophy type 1 (DM1) is a multisystem genetic disorder caused by a triplet nucleotide repeat expansion in the 3' untranslated region of the Dystrophia Myotonica-Protein Kinase (DMPK) gene. DMPK gene transcripts containing CUG expanded repeats accumulate in nuclear foci and ultimately cause altered splicing/gene expression of numerous secondary genes. The study of primary cell cultures derived from patients with DM1 has allowed the identification and further characterization of molecular mechanisms underlying the pathology in the natural context of the disease. In this study we show for the first time impaired nuclear structure in fibroblasts of DM1 patients. DM1-derived fibroblasts exhibited altered localization of the nuclear envelope (NE) proteins emerin and lamins A/C and B1 with concomitant increased size and altered shape of nuclei. Abnormal NE organization is more common in DM1 fibroblasts containing abundant nuclear foci, implying expression of the expanded RNA as determinant of nuclear defects. That transient expression of the DMPK 3' UTR containing 960 CTG but not with the 3' UTR lacking CTG repeats is sufficient to generate NE disruption in normal fibroblasts confirms the direct impact of mutant RNA on NE architecture. We also evidence nucleoli distortion in DM1 fibroblasts by immunostaining of the nucleolar protein fibrillarin, implying a broader effect of the mutant RNA on nuclear structure. In summary, these findings reveal that NE disruption, a hallmark of laminopathy disorders, is a novel characteristic of DM1.

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Even though the Duchenne muscular dystrophy (DMD) gene product Dystrophin Dp71d is involved in various key cellular processes through its role as a scaffold for structural and signalling proteins at the plasma membrane as well as the nuclear envelope, its subcellular trafficking is poorly understood. Here we map the nuclear import and export signals of Dp71d by truncation and point mutant analysis, showing for the first time that Dp71d shuttles between the nucleus and cytoplasm mediated by the conventional nuclear transporters, importin (IMP) α/ß and the exportin CRM1. Binding was confirmed in cells using pull-downs, while in vitro binding assays showed direct, high affinity (apparent dissociation coefficient of c. 0.25nM) binding of Dp71d to IMPα/ß. Interestingly, treatment of cells with the microtubule depolymerizing reagent nocodazole or the dynein inhibitor EHNA both decreased Dp71d nuclear localization, implying that Dp71d nuclear import may be facilitated by microtubules and the motor protein dynein. The role of Dp71d in the nucleus appears to relate in part to interaction with the nuclear envelope protein emerin, and maintenance of the integrity of the nuclear architecture. The clear implication is that Dp71d's previously unrecognised nuclear transport properties likely contribute to various, important physiological roles.

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Spinocerebellar ataxias (SCA) are a heterogeneous group of neurodegenerative disorders. CAG (cytosine-adenine-guanine) trinucleotide repeat expansions in the causative genes have been identified as the cause of different SCA. In this study, we simultaneously genotyped SCA1, SCA2, SCA3, SCA6, and SCA7 applying a fluorescent multiplex polymerase chain reaction assay. We analyzed 10 families with SCA (64 patients) from five different communities of Veracruz, a Mexican southeastern state, and identified 55 patients for SCA7 and 9 for SCA2, but none for SCA1, SCA3, or SCA6. To our knowledge, this sample represents one of the largest series of SCA7 cases reported worldwide. Genotyping of 300 healthy individuals from Mexican population and compiled data from different ethnicities showed discordant results concerning the hypothesis that SCA disease alleles arise by expansion of large normal alleles.

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Spinocerebellar ataxia type 7 (SCA7) is a neurodegenerative disorder characterized by progressive cerebellar ataxia associated with macular degeneration that leads, in the majority of patients, to loss of autonomy and blindness. The cause of the disease has been identified as (CAG) n repeat expansion in the coding sequence of the ATXN7 gene on chromosome 3p21.1. SCA7 is one of the least common genetically verified autosomal dominant cerebellar ataxias found worldwide; however, we previously identified the Mexican population showing high prevalence of SCA7, suggesting the occurrence of a common founder effect. In this study, haplotype analysis using four SCA7 gene-linked markers revealed that all 72 SCA7 carriers studied share a common haplotype, A-254-82-98, for the intragenic marker 3145G/A and centromeric markers D3S1287, D3S1228, and D3S3635, respectively. This multiloci combination is uncommon in healthy relatives and Mexican general population, suggesting that a single ancestral mutation is responsible for all SCA7 cases in this population. Furthermore, genotyping using 17 short tandem repeat markers from the non-recombining region of the Y chromosome and further phylogenetic relationship analysis revealed that Mexican patients possess the Western European ancestry, which might trace the SCA7 ancestral mutation to that world region.

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The Acquired Immunodeficiency Syndrome (AIDS) constitutes the main infectious cause of death in adults worldwide. Epidemiological data suggest the existence of differences in viral load and CD4(+) T lymphocytes cell counts related to gender. Women have more favorable clinical and viro-immunological patterns than men in early infection, although once established the infection these patterns are reversed. Increasing evidence shows that estradiol (E) and progesterone (P) participate in the regulation of several infections, such as that produced by human immunodeficiency virus (HIV). Several functions of these hormones involve the interaction with their intracellular receptors (ER and PR, respectively). During infection, E and P not only exert their action upon the immune system, but also directly act on the virus. Effects of E and P depend on their concentration or the phase of HIV infection but in general terms, they could exert a protective role against HIV infection.

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Resistance to gastrointestinal conditions is a requirement for bacteria to be considered probiotics. In this work, we tested the resistance of six different Lactobacillus strains and the effect of carbon source to four different gastrointestinal conditions: presence of α-amylase, pancreatin, bile extract and low pH. Novel galactooligosaccharides synthesized from lactulose (GOS-Lu) as well as commercial galactooligosaccharides synthesized from lactose (GOS-La) and lactulose were used as carbon sources and compared with glucose. In general, all strains grew in all carbon sources, although after 24 h of fermentation the population of all Lactobacillus strains was higher for both types of GOS than for glucose and lactulose. No differences were found among GOS-Lu and GOS-La. α-amylase and pancreatin resistance was retained at all times for all strains. However, a dependence on carbon source and Lactobacillus strain was observed for bile extract and low pH resistance. High hydrophobicity was found for all strains with GOS-Lu when compared with other carbon sources. However, concentrations of lactic and acetic acids were higher in glucose and lactulose than GOS-Lu and GOS-La. These results show that the resistance to gastrointestinal conditions and hydrophobicity is directly related with the carbon source and Lactobacillus strains. In this sense, the use of prebiotics as GOS and lactulose could be an excellent alternative to monosaccharides to support growth of probiotic Lactobacillus strains and improve their survival through the gastrointestinal tract.

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Three different stationary phases (sulfoalkylbetaine zwitterionic, polyhydroxyethyl aspartamide and ethylene bridge hybrid (BEH) with trifunctionally bonded amide), operating at hydrophilic interaction liquid chromatographic (HILIC) mode, have been assayed and compared for the analysis of complex mixtures of galactooligosaccharides (GOS). Chromatographic methods have been optimized to obtain the best separation between two consecutive galactose containing standards and maltodextrins, measured on the basis of resolution. Influence of several factors such as chemical modifiers (formic acid, ammonium acetate and ammonium hydroxide), organic solvent and gradients of the mobile phases in the separation of oligosaccharides have been studied. The best results were achieved on the BEH amide stationary phase, using acetonitrile:water with 0.1% ammonium hydroxide as mobile phase, where the most of oligosaccharides were successfully resolved. Characteristic MS(2) fragmentation profiles of disaccharides containing galactose, glucose and/or fructose units with different linkages were evaluated and used for the characterization of di-, tri- and tetrasaccharides of three commercial prebiotic GOS mixtures (GOS-1, GOS-2 and GOS-3) by HILIC-MS(n). Similar qualitative and quantitative composition was observed for GOS-1 and GOS-3, whereas different linkages and abundances were detected for GOS-2. In general, (1→4) and (1→6) glycosidic linkages were the main structures found in GOS, although (1→2) and (1→3) linkages were also identified. Regarding molecular weight, up to pentasaccharides were detected in these samples, disaccharides being the most abundant carbohydrates.

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GC and GC-MS are excellent techniques for the analysis of carbohydrates; nevertheless the preparation of adequate derivatives is necessary. The different functional groups that can be found and the diversity of samples require specific methods. This review aims to collect the most important methodologies currently used, either published as new procedures or as new applications, for the analysis of carbohydrates. A high diversity of compounds with diverse functionalities has been selected: neutral carbohydrates (saccharides and polyalcohols), sugar acids, amino and iminosugars, polysaccharides, glycosides, glycoconjugates, anhydrosugars, difructose anhydrides and products resulting of Maillard reaction (osuloses, Amadori compounds). Chiral analysis has also been considered, describing the use of diastereomers and derivatives to be eluted on chiral stationary phases.

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La esporotricosis es la micosis subcutánea más frecuente en México, cuyo agente causal es Sporothrix schenckii y se considera en algunos casos como una zoonosis. Se presente el caso de una paciente femenina de 43 años, con nódulos ulcerados en el antebrazo después de haber sido arañada por su gato, quien igualmente tenía lesiones en su cuerpo. La paciente se diagnosticó clínica y micológicamente como una esporotricosis linfangítica. Recibió itraconazol 200 mg/día por 3 meses con resolución de las lesiones (AU)

Sporotrichosis is the most common subcutaneous mycosis in Mexico which is caused by Sporothrix schenckii and in some cases it has been consideredas a zoonosis. A 43-year-old women who developed ulcerated nodules in her forearm after a scratch of her cat which also has lesions in his body, isreported. The patient had a clinic and mycological diagnosis of lymphocutaneous sporothrichosis. Itraconazol 200 mg/daily during 3 months was given with complete remission (AU)

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In his thesis inspired on Favre's works, Phylactos (in 1922) synthetized the knowledges prevailing then on the disease which was characterized in 1913 by Durand, Nicolas, and Favre. He distinguished this disease from tuberculosis, Hodgkin's disease, pestis, syphilis, and chancroid, thus establishing the basic elements of the clinical diagnosis of lymphogranuloma venereum. In 1924, Gamma described the intracellular inclusions, thus giving rise to the biological diagnosis. In 1925, Frei proved that the heated pus filtrate obtained from buboes induced a specific intradermal reaction. In 1927, Gay Prieto described the elementary corpuscles.

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