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There are few studies in Mexico aimed at evaluating the genetic variability of Sechium spp. Despite certain biological variants are reported with very high potential to develop antineoplastic supplements to treat public health conditions. Using the Amplified Fragment Length Polymorphism (AFLP) technique, the genetic variability of a sample of 95 accessions of three species of Sechium (S. edule, S. chinantlense, S. compositum) was evaluated, with leaf DNA from the Banco Nacional de Germoplasma de Sechium edule en Mexico. Four combinations of AFPL were applied (EcoRI + ACC/MseI + CAC, EcoRI + ACC/MseI + CAT, EcoRI + ACC/MseI + CGC, and EcoRI + ACC/MseI + CGG). DNA samples were classified into three groups based on the flavour of the fruit (sweet, neutral, bitter). An average of 47.91% polymorphism, 0.16 heterozygosity, 32.83 number of polymorphic bands, and a zero Wright fixation index (Fst) was obtained. The evidence showed that the domesticated accessions (sweet, neutral) were separated from the bitter-taste genotypes. A monophyletic tree was generated with the genetic distance matrix and the neighbour-joining methodology. Analyses showed S. edule as the root taxon, deriving S. compositum and S. chinantlense as subgroups, and suggesting that there is not enough differentiation to treat them as separate species. The evaluated sample showed that there is no apparent reproductive barrier for genetic cross breeding. Genotypes behaved as a complex with evolutive dynamism; that genetic complexity would allow the design of new variants. [ABSTRACT FROM AUTHOR]

Using tropical and highland pre-commercial hybrids available from Masagro collaborative team, the objectives of this study were (1) to evaluate the influence of genotype and environmental adaptation on grain and tortilla quality properties; (2) to investigate relationships between agronomic traits, grain properties, and tortilla quality properties; and (3) to identify the most stable and best hybrids in terms of grain quality to be recommended to the masa-tortilla and nixtamalized flour industries. Kernels from highland adapted hybrids were softer (flotation index (FI) = 68%) than kernels from tropical adapted hybrids (FI = 15%). Highland adapted hybrids yield more tortillas (1.45 kg kg−1maize), which were softer (197 gf) and lighter (92% reflectance) than the ones obtained from tropical adapted hybrids (1.38 kg kg−1maize; 271.5 gf, and 88% reflectance, respectively). Correlations between grain yield and all grain and quality parameters were low, suggesting that it is possible to breed simultaneously to increase grain yield and ensure excellent nixtamalized quality parameters. [ABSTRACT FROM PUBLISHER]

Introduction: Hepatitis C virus is the main cause of posttransfusional hepatitis. Because it is considered as a public health problem, its transcendental to estimate the frequency and distribution of hepatitis C genotype in our country, in order to obtain a better epidemiological profile for each genotype in Mexican population. Methods: 403 samples were analyzed from hepatitis C patients of Unidad de Patología Clínica. The genotype was obtained by means of LiPA, viral load was estimated with COBAS AMPLICOR test and the statistical analysis with EBM calculator program. Results: 60% of patients were women and 39.7% men. The genotype frequencies were: 58.3% type 1, 30.5% type 2, 8.7% type 3, 1% type 4, 1.5% mix types. The frequencies of subtypes were: 1b 26.8%, 1a 21.3%, 2a/2c 12.4%, 2b 9.2%, 3a 8.4%. The distribution of genotype by region of the country was: North n = 43 1b 46%, 1a 18.6%, 2a/2c 9.3%, 2b 7%; West and Central n = 345 1b 24.1%, 1a 20.9 %, 2a/2c 13.3%, 2a 9.6%, 3a 9.6%; South n = 15 1a 40%, 1b 33%, 1a/1b 20%, 2b 7%. In 289 patients the viral load was: 69% within linear range (average 314,375 UI/mL) and the 31% greater than the upper limit, with viral load > 700,000 UI/mL. Conclusion: The 1b genotype was the most frequent. This study showed different VHC genotype frequencies within the country, besides against other populations, which the predominant genotypes are mainly 2a/2c. [ABSTRACT FROM AUTHOR]

Antecedentes: El cáncer de laringe representa el 21.7% de las neoplasias malignas de vías aerodigestivas superiores. La prevalencia del virus del papiloma humano (VPH) en el cáncer de laringe oscila entre el 0 y el 80%., Método: Se incluyeron 112 muestras de tejido laríngeo de pacientes con cáncer de laringe. Se amplificó el ADN y se analizó la presencia y el genotipo del VPH mediante hibridación reversa (INNO-LiPA ® ). Se realizaron pruebas de ji cuadrada, Fisher y t de Student no pareada., Resultados: Se incluyeron muestras de 107 hombres (95.5%) y 5 mujeres (4.5%), con una edad de 65.3 ± 10.1 años, con antecedente de tabaquismo 108 (96.4%), alcoholismo 9 (8.0%) y carcinoma epidermoide moderadamente diferenciado queratinizante 96 (85.7%). Se identificó VPH en 60 (53.5%), VPH-11 en 51 (45.5%), VPH-52 en 27 (24.1%), VPH-16 en 9 (8.0%), VPH-45 en 3 (2.6%) y coinfección por más de un genotipo en 31 (27.6%). No hubo diferencia entre pacientes con y sin infección por VPH en cuanto a edad, sexo, localización, diagnóstico histopatológico, tabaquismo ni alcoholismo (p > 0.05)., Conclusiones: La prevalencia de infección por VPH en el cáncer de laringe fue del 53.5%, con coinfección por más de un genotipo en el 27.6%. El genotipo más frecuente fue el VPH-11, tipo de bajo riesgo, seguido por el VPH-52, de alto riesgo oncogénico., Background: Laryngeal cancer represents 21.7% of malignancies of the upper aerodigestive tract. The prevalence of the Human Papillomavirus (HPV) in laryngeal cancer ranges 0 to 80%., Methods: We included 112 laryngeal tissue samples obtained from patients with laryngeal cancer. DNA was extracted and amplified by PCR. HPV presence and genotype were analyzed by the reverse hybridization INNO-LiPA ® assay. Chi-square, Fisher’s and unpaired Student t tests were used., Results: Samples from 107 male (95.5%) and 5 female patients (4.5%) were evaluated, aged 65.3±10.1 years, 108 with smoking history (96.4%), 9 with alcoholism history (8.0%), and in 96 the histological diagnosis was moderately differentiated keratinizing squamous cell carcinoma (85.7%). HPV was detected in 60 samples (53.5%), HPV-11 in 51 (45.5%), HPV-52 in 27 (24.1%), HPV-16 in 9 (8.0%), HPV-45 in 3 (2.6%), and coinfection by more than one genotype in 31 (27.6%). There was no difference between patients with and without HPV infection with respect to age, sex, tumor location and histology, smoking and alcoholism history (p>0.05)., Conclusions: The prevalence of HPV infection in laryngeal cancer was 53.5% with coinfection with more than one genotype in 27.6%. The most frequent genotype was HPV-11, an oncogenic low-risk genotype, followed by HPV-52, a high-risk genotype., (Copyright: © 2018 Permanyer.)

Background: Childhood acute leukemia cytological features are unknown in Chiapas, Mexico. Defining these features is important because this is a relatively isolated population with high consanguinity index, and these aspects could determine differences in responses to treatment and outcome., Methods: Eighty-one childhood acute leukemia cases treated at the Hospital de Especialidades Pediátricas in Chiapas were characterized by morphology, immunophenotype, genotype, initial risk assignment and status at the time of the study., Results: The proportion of leukemic cell types found in this study was B cell, 75.3%; myeloid, 16%; T cell, 3.7% and NK 1.2%. In B cell leukemia, genetic alterations were present in 40.6% of cases and had a specific outcome regardless of initial risk assessment. Cases with MLL gene alteration died within a month from diagnosis. Translocations were present in 17.5% B cases; t(1;19) was present in those with a favorable outcome. The t(12;21) translocation was related to initial remission and midterm relapse and dead. Hyperdiploidy was present in 20% of B cell cases with good outcome. In 38.5%of myeloid cases were translocations and karyotypic abnormalities. Short-term outcome in this group has been poor; 69% have died or abandoned treatment in relapse from 15 days to 37 months after diagnosis., Conclusions: Relative frequency of different types of acute leukemia in patients treated at a tertiary level pediatric hospital in Chiapas, Mexico, was similar to the one found in other parts of the country. Patients' outcome, under a standardized treatment, differs according to the group, the subgroup and the presence and type of genetic alterations., (Copyright © 2017 Hospital Infantil de México Federico Gómez. Publicado por Masson Doyma México S.A. All rights reserved.)