Because Candida species have innately highly variable antifungal susceptibilities, the availability of a fast and reliable species identification test is very important so that suitable and effective therapeutic measures may be taken. Using three oligonucleotide primers, we established a randomly amplified polymorphic DNA (RAPD) analysis method that enabled direct identification of the most common opportunistic pathogenic Candida species. RAPD analysis revealed a characteristic molecular fingerprint for each Candida species. Differences between the profiles for Candida albicans and C. dubliniensis were evident. RAPD analysis is a relatively easy, reproducible, and reliable technique that can be useful in providing genetic fingerprints for the identification of strains. In addition, a collection of different C. albicans strains was identified by a specific PCR based on multiple secreted aspartic proteinase ( SAP ) genes and the dipeptidyl aminopeptidase ( DAP2 ) gene. Our findings demonstrate that PCR based upon the SAP and DAP2 sequences is a simple, rapid, clear, and direct technique for the identification and differentiation of C. albicans and C. dubliniensis .

The genetic diversity of 47 clinical and reference strains of Candida glabrata from several geographical origins and diverse clinical disorders, with different antifungal susceptibilities, as well as their genetic relationships were studied through multilocus enzyme electrophoresis (MLEE) and randomly amplified polymorphic DNA (RAPD) techniques. The genetic diversity estimated for 11 MLEE loci measured as average heterozygosity ( h ) was 0.055. A high level of genetic relatedness among isolates was established by cluster analysis. Forty-nine RAPD markers were analyzed, and the average genetic diversity among isolates, estimated by Shannon's index ( H _o ), was 0.372. The Φ _ST values estimated through an analysis of molecular variance to assess genetic differentiation among isolates revealed no genetic differentiation among them. Our results revealed very low genetic diversity among isolates, a lack of differentiation, and no association with their geographic origin and the clinical characteristics.

HNF1A gene regulates liver‐specific genes, and genes that have a role in glucose metabolism, transport, and secretion of insulin. HNF1A gene mutations are frequently associated with type 2 diabetes. HNF1A protein has three domains: the dimerization domain, the DNA‐binding domain, and the trans‐activation domain. Some mutations in the dimerization or DNA‐binding domains have no influence on the normal allele, while others have dominant negative effects. The I27L, A98V, and S487N polymorphisms are common variants of the HNF1A gene; they have been found in T2D and non‐diabetic subjects. We searched for mutations in the first three exons of the HNF1A gen in an Amerindian population of 71 diabetic patients. DNA sequencing revealed the previously reported I27L polymorphism (c.79A>C) in 53% of diabetic patients and in 67% of the control group. Thus, the I27L/L27L polymorphism might be a marker of Amerindians. In addition, we found the c.422_423InsT mutation in the HNF1A gene of one patient, which had not been previously reported. This mutation resulted in a frame shift of the open reading frame and a new translation stop in codon 187, leading to a truncated polypeptide of 186 amino acids (Q141Hfs*47). This novel mutation affects the DNA‐binding capacity of the mutant HNF1A protein by EMSA; its intracellular localization by fluorescence and confocal microscopy, and a dominant‐negative effect affecting the DNA‐binding capacity of the normal HNF1A by EMSA. We also studied the homology modeling structure to understand the effect of this mutation on its DNA‐binding capacity and its dominant negative effect. The HNF1A Q141Hfs*47 mutant polypeptide has no DNA‐binding capacity and exerts a dominant negative effect on the HNF1A protein. Therefore, it might produce severe phenotypic effects on the expression levels of a set of β‐cell genes. Consequently, its screening should be included in the genetic analysis of diabetic patients after more functional studies are performed.

To describe the geographical distribution of dengue fever cases in flooded areas of Villahermosa, Tabasco, in 2010. Cross-sectional, descriptive study. Universe: Colonies with antecedents of flooding during the inundation of the State, located in Villahermosa, Tabasco: Gaviotas Norte, Gaviotas Sur, La Manga 1th Section, La Manga 2nd Section and La Manga 3th Section. Convenience sample without randomization. location, dengue fever case. descriptive statistic. Software: SPSS version 11.0. 540 individuals were included. The distribution was: Gaviotas Norte, 36.1%; Gaviotas Sur, 24.8%; La Manga 1th Section, 13.8%; La Manga 2nd Section, 13.2%; and La Manga 3th Section, 12.1%. We found three cases with positive serology of IgG (0.6%) and five cases of positive IgM (0.9%). The geographical distribution was associated with the proximity to two water bodies: Rio Grijalva and Laguna El Encanto. It is necessary to reinforce preventive interventions in the proximity of bodies of fresh water.

Objetivo. Evaluar la calidad higiénico-sanitaria, fisicoquímica y microbiológica de leche cruda bovina destinada a la venta, producida en un establo familiar y en tres mercados públicos del estado de Tabasco. Materiales y métodos. La calidad higiénico-sanitaria se determinó de acuerdo con la información general del predio, instalaciones, proceso de ordeño, limpieza y desinfección. La calidad fisicoquímica se determinó evaluando proteínas totales, caseína, grasa butírica, lactosa, sólidos no grasos y densidad. La calidad microbiológica fue determinada mediante la acidez titulable, prueba de alcohol, contenido de células somáticas, potencial de óxido-reducción, materia extraña, inhibidores bacterianos y bacterias mesofílicas aerobias. Resultados. La leche producida en el establo familiar, fue evaluada con la máxima calidad fisicoquímica y microbiológica en referencia a los estándares que evalúa la normatividad oficial mexicana establecidas en México por el Consejo para el fomento de la calidad de la leche y sus derivados, A. C. En cambio, la leche en los tres mercados públicos se consideró de rechazo, indicando posible contaminación durante los procesos de ordeña, así como en el manejo y transporte hacia los mercados públicos. Conclusiones. Las muestras de leche provenientes de los mercados públicos se consideraron no aptas para consumo humano ni para elaboración de subproductos.

The present study assessed the effectiveness of phytoremediation and natural attenuation in removing total petroleum hydrocarbons (TPH) from clayey soils in the Mexican humid tropics for 12 months under mini-greenhouse conditions. The experiment was performed using a 4 × 2 × 2 factorial design with four crude oil concentrations, two technologies (phytoremediation with Leersia hexandra Swartz and natural attenuation with native microorganisms), and two exposure times (6 and 12 months). The results showed soil microbial respiration increased due to crude oil concentration and exposure time effects; however, crude oil induced population inhibition of Pseudomonas spp. After 12 months of exposure, the rhizosphere of L. hexandra achieved a total of 62.9%, 40.2%, and 33.1% crude oil removal from soils initially containing 30, 60, and 90 g kg^-1, whereas natural attenuation achieved 74.8%, 43.7%, and 35.2% removal, respectively. The maximum removal capacity was 30.7 ± 1.3 g kg^-1 crude oil for both technologies at 90 g kg^-1 crude oil. P. aeruginosa, P. taiwanensis, P. entomophila, P. mosselii, and P. agglomerans were identified in soils with crude oil. These findings highlights the need to integrate biotic and abiotic interactions in the development of bioremediation strategies for tropical soils contaminated with light crude oil.