Asociación entre presencia del virus del papiloma humano y hallazgos anatomo-patológicos / Association between the presence of human papilloma virus and pathological findings

OBJETIVO: Determinar por reacción en cadena de la polimerasa la presencia del virus del papiloma humano en pacientes femeninas, quienes acudieron a un tamizaje de lesiones en cuello uterino en la red ambulatoria del Municipio Francisco Linares Alcántara (Edo. Aragua) y asociar la presencia de virus del papiloma humano con hallazgos anatomo-patológicos. MÉTODOS: Luego de obtener el consentimiento informado se tomó una muestra de hisopado vaginal a 301 pacientes, a quienes se les realizó citología y colposcopia. Se aisló ADN para la genotipificación mediante ensayos de reacción en cadena de la polimerasa acoplados a digestión con enzimas de restricción. Se efectuaron pruebas estadísticas para analizar la relación entre la presencia de virus del papiloma humano y las variables: edad, inicio de relaciones sexuales, número de parejas sexuales y hallazgos citológicos y colposcópicos. RESULTADOS: Se obtuvieron 43 muestras positivas para virus del papiloma humano 17 fueron 16 (39,53.%), 3 virus del papiloma humano 18 (6,98 %), 1 virus del papiloma humano 33 (2,33 %), 14 muestras presentaron coinfección (32,56 %) y en 8 muestras (18,60 %) no ocurrió digestión con las enzimas utilizadas. Existen relaciones estadísticas significativas entre la presencia de virus del papiloma humano y las variables analizadas. CONCLUSIÓN: La presencia de genotipos de alto riesgo en el 48,84 % de las pacientes con virus del papiloma humano, es una situación preocupante, dada la vinculación de dichos genotipos al desarrollo de cáncer de cuello uterino

OBJECTIVE: To determine by Polymerase Chain Reaction the presence of the human papillomavirus in female patients attending a screening for lesions of uterine neck in the outpatient network of Francisco Linares Alcantara Municipality and to relate the results to anatomopathological findings. METHODS: After obtaining informed consent from patients, samples of vaginal swabs were taken from 301 women that were used for cytology and colposcopy studies. Also, DNAs were isolated and they were used for Polymerase Chain Reaction test coupled to restriction enzyme digestion. Statistical tests were performed to analyze the relationship between the human papillomavirus positivity and the variables: stratus age, the onset of sexual activity, number of sexual couple, cytology and colposcopy findings. RESULTS: Out of 43 human papillomavirus positive samples, 17 (39.53 %) were genotype 16, 3 (6.98 %) genotype 18 and 1 (12.33.%) genotype 33; 14 (32.56 %) samples showed coinfection and 8 (18.60 %), samples were not digested with the restriction enzymes used. The relationship between the presence of human papillomavirus and the others studied variables (stratus age, the onset of sexual activity, number of sexual couple and cytological results) was statistically significant. CONCLUSIONS: The presence of human papillomavirus genotypes, of so-called high risk in the 48.84 % of the women with a positive HPV test is a particular concern, because they are associated with the development of cervical cancer.

Análisis filogenético de cepas Venezolanas del virus de la encefalitis equina del este / Phylogenetic Analysis of Venezuelan Strains of the Eastern Equine Encephalitis Virus

Se realizó un estudio molecular de cinco cepas de virus de encefalitis equina del este (VEEE) mediante secuenciación de productos obtenidos en el ensayo de transcriptasa reversa acoplada a la reacción en cadena de la polimerasa (RT-PCR, por sus siglas en inglés). Secuencias de ~ 500 pb de la región 3’ no traducible del genoma se compararon con secuencias homólogas variantes Sur Americana (SA) y Norte Americana (NA) del complejo VEEE. La cepa EE VE02 EL PAO, con la cual se desarrolló una vacuna inactivada oleosa tuvo más similitud con la cepa EE VE76 EL DELIRIO, seguida por EE VE75 CATATUMBO,  EE VE96 MLLANO y EE VE84 TUCACAS respectivamente. La alineación de secuencias entre las cepas típicas reveló diferencias de 2,82 a 8,48 %. En tanto que, la cepa EE VE02 EL PAO difirió en un 8,86 % de la de Perú (EE PE-0,0155 del linaje III) y en un 38,08 % de la de EEUU (EE-PE-6 del linaje I, usada en vacunas comerciales). Los resultados indican que las cepas autóctonas tuvieron más similitud con la cepa SA, que con la NA. Se han identificado cuatro principales linajes en el complejo de VEEE (I-IV). El árbol filogenético evidenció dos clado: uno que agrupa los linajes I-III y el otro, el linaje IV. La mayoría de las secuencias están contenidas en el primer clado que, a su vez, se separa en dos grupos que contienen secuencias del linaje I y secuencias de los linajes  II-III y, debido al valor bootstrap alto (99%), los grupos se consideran completamente distintos. Sin embargo, éste no es el caso del grupo que contiene a los linajes II-III porque éstos se separan sólo el 53% de las veces, pero se asume que las cepas venezolanas pertenecen al linaje III dividido en dos subclados: IIIA y IIIB.

A molecular study of five strains of the eastern equine encephalitis virus (EEEV) was conducted by sequencing of products generated using the reverse transcriptase assay, coupled to the polymerase chain reaction (RT-PCR). Sequences of approximately 500 pair of bases from the non-translated 3’ region of the genome were compared with homologous sequences of the South American (SA) and North American (NA) variants of the EEEV complex. The EE VE02 EL PAO strain, used to develop an inactivated oil vaccine had most resemblance with the EE VE76 EL DELIRIO strain, followed by the EE VE75 CATATUMBO, the EE VE96 MLLANO and the EE VE84 TUCACAS strains, respectively. The alignment of sequences among typical strains revealed differences of 2.82 and 8.48%, respectively, while the EE VE02 EL PAO strain differed in 8.86% from the Perú strain (EE PE-0.0155, from lineage III) and in 38.08% from the NA strain (EE-PE-6, from lineage I, used in commercial vaccines). The results of the present investigation indicate that the autochthonous strains have more similarly with the SA strain than with the NA strain. Four major lineages (I-IV) in the EEEV complex have been identified. The phylogenetic tree evidenced two clades, one which groups lineages I-III and another, lineage IV. Most of the sequences are contained in the first clade, which at the same time, separates into two groups containing sequences of lineage I and lineages II-III; and, due to the high bootstrap value (99%) the groups are considered completely different. However, this was not the case of the group which enclosed the lineages II and III; because these only separate 53% of the time, but it is assumed that the Venezuelan strains belong to linage III, which diverges into two subclades: IIIA and IIIB.

Similarity between the association factor of ribosomal subunits and the protein Stm1p from Saccharomyces cerevisiae

A ribosome association factor (AF) was isolated from the yeast Sacchharomyces cerevisiae. Partial amino acid sequence of AF was determined from its fragment of 25 kDa isolated by treating AF with 2-(2-nitrophenylsulfenyl)-3-methyl-3'-Bromoindolenine (BNPS-skatole). This sequence has a 86 percent identity to the product of the single-copy S. cerevisiae STM1 gene that is apparently involved in several events like binding to quadruplex and triplex nucleic acids and participating in apoptosis, stability of telomere structures, cell cycle, and ribosomal function. Here we show that AF and Stm1p share some characteristics: both bind to quadruplex and Pu triplex DNA, associates ribosomal subunits, and are thermostable. These observations suggest that these polypeptides belong to a family of proteins that may have roles in the translation process.

An in vitro system from Plasmodium falciparum active in endogenous mRNA translation

An in vitro translation system has been prepared from Plasmodium falciparum by saponin lysis of infected-erythrocytes to free parasites which were homogeneized with glass beads, centrifuged to obtain a S-30 fraction followed by Sephadex G-25 gel filtration. This treatment produced a system with very low contamination of host proteins (<1). The system, optimized for Mg2+ and K+, translates endogenous mRNA and is active for 80 min which suggests that their protein factors and mRNA are quite stable.