Autophagy analysis in oral carcinogenesis.

OBJECTIVE: The aim of this study was to evaluate the levels of autophagy in oral leukoplakia and squamous cell carcinoma and to correlate with clinical pathological features, as well as, the evolution of these lesions. METHODOLOGY: 7 Normal oral mucosa, 51 oral leukoplakias, and 120 oral squamous cell carcinomas (OSCC) were included in the study. Histological sections of the mucosa and leukoplakias were evaluated throughout their length, while the carcinomas were evaluated using Tissue Microarray. After the immunohistochemical technique, LC3-II positive cells were quantified in the different epithelial layers of the mucosa and leukoplakias and in the microarrays of the squamous cell carcinomas. The correlation between positive cells with the different clinical-pathological variables and with the evolution of the lesions was tested using the t test, ANOVA, and Kaplan-Meier survival analysis. RESULTS: We observed increased levels of autophagy in the oral squamous cell carcinomas (p<0.001) in relation to the other groups, but without any association with poorer evolution or survival of these patients. Among the leukoplakias, we observed a higher percentage of positive cells in the intermediate layer of the dysplastic leukoplakias (p=0.0319) and in the basal layer of lesions with poorer evolution (p=0.0133). CONCLUSION: The levels of autophagy increased during the process of oral carcinogenesis and are correlated with poorer behavior of the leukoplakias.

Selo SINASC 2009: Certificado da qualidade das informações sobre Nascidos Vivos na cidade de São Paulo

Traz estudo sobre o Selo SINASC, lançado em dezembro de 2008. Uma iniciativa de melhoria da qualidade da coleta, preenchimento e digitação das informações da DN que, em São Paulo, são processadas pelos estabelecimentos que realizam partos

Selo SINASC 2009: Certificado da qualidade das informações sobre Nascidos Vivos na cidade de São Paulo / Seal SINASC 2009: Certificate of quality of information on live births in São Paulo

Traz estudo sobre o Selo SINASC, lançado em dezembro de 2008. Uma iniciativa de melhoria da qualidade da coleta, preenchimento e digitação das informações da DN que, em São Paulo, são processadas pelos estabelecimentos que realizam partos

Dengue virus-induced regulation of the host cell translational machinery

Dengue virus (DV)-induced changes in the host cell protein synthesis machinery are not well understood. We investigated the transcriptional changes related to initiation of protein synthesis. The human hepatoma cell line, HepG2, was infected with DV serotype 2 for 1 h at a multiplicity of infection of one. RNA was extracted after 6, 24 and 48 h. Microarray results showed that 36.5 percent of the translation factors related to initiation of protein synthesis had significant differential expression (Z-score ≥ ±2.0). Confirmation was obtained by quantitative real-time reverse transcription-PCR. Of the genes involved in the activation of mRNA for cap-dependent translation (eIF4 factors), eIF4A, eIF4G1 and eIF4B were up-regulated while the negative regulator of translation eIF4E-BP3 was down-regulated. This activation was transient since at 24 h post-infection levels were not significantly different from control cells. However, at 48 h post-infection, eIF4A, eIF4E, eIF4G1, eIF4G3, eIF4B, and eIF4E-BP3 were down-regulated, suggesting that cap-dependent translation could be inhibited during the progression of infection. To test this hypothesis, phosphorylation of p70S6K and 4E-BP1, which induce cap-dependent protein synthesis, was assayed. Both proteins remained phosphorylated when assayed at 6 h after infection, while infection induced dephosphorylation of p70S6K and 4E-BP1 at 24 and 48 h of infection, respectively. Taken together, these results provide biological evidence suggesting that in HepG2 cells DV sustains activation of the cap-dependent machinery at early stages of infection, but progression of infection switches protein synthesis to a cap-independent process.

Dengue virus-induced regulation of the host cell translational machinery.

Dengue virus (DV)-induced changes in the host cell protein synthesis machinery are not well understood. We investigated the transcriptional changes related to initiation of protein synthesis. The human hepatoma cell line, HepG2, was infected with DV serotype 2 for 1 h at a multiplicity of infection of one. RNA was extracted after 6, 24 and 48 h. Microarray results showed that 36.5% of the translation factors related to initiation of protein synthesis had significant differential expression (Z-score >or= +/-2.0). Confirmation was obtained by quantitative real-time reverse transcription-PCR. Of the genes involved in the activation of mRNA for cap-dependent translation (eIF4 factors), eIF4A, eIF4G1 and eIF4B were up-regulated while the negative regulator of translation eIF4E-BP3 was down-regulated. This activation was transient since at 24 h post-infection levels were not significantly different from control cells. However, at 48 h post-infection, eIF4A, eIF4E, eIF4G1, eIF4G3, eIF4B, and eIF4E-BP3 were down-regulated, suggesting that cap-dependent translation could be inhibited during the progression of infection. To test this hypothesis, phosphorylation of p70S6K and 4E-BP1, which induce cap-dependent protein synthesis, was assayed. Both proteins remained phosphorylated when assayed at 6 h after infection, while infection induced dephosphorylation of p70S6K and 4E-BP1 at 24 and 48 h of infection, respectively. Taken together, these results provide biological evidence suggesting that in HepG2 cells DV sustains activation of the cap-dependent machinery at early stages of infection, but progression of infection switches protein synthesis to a cap-independent process.

CYP3A5 genotype has no impact on plasma trough concentrations of lopinavir and ritonavir in HIV-infected subjects.

CYP3A5 genotype has no impact on the trough plasma concentrations of lopinavir and ritonavir in human immunodeficiency virus (HIV)-infected individuals on stable highly active antiretroviral therapy (HAART). This is ascribed to a drug interaction, such that ritonavir by inhibiting CYP3A activity, may occlude the pharmacokinetic consequences of functional polymorphisms in the CYP3A5 gene. In the clinical setting, where lopinavir and ritonavir are always combined, CYP3A5 genotype is of no consequence on the trough plasma concentrations of these drugs.

Human serine racemase: moleular cloning, genomic organization and functional analysis.

High levels of D-serine are found in mammalian brain, where it is an endogenous agonist of the strichinine-insensitive site of N-methyl D-aspartate type of glutamate receptors. D-serine is enriched in protoplasmic astrocytes that occur in gray matter areas of the brain and was shown to be synthesized from L-serine. We now report cloning and expression of human serine racemase, an enzyme that catalyses the synthesis of D-serine from L-serine. The enzyme displays a high homology to the murine serine racemase. It contains a pyridoxal 5'-phosphate attachment sequence similar to bacterial biosynthetic threonine dehydratase. Northern-blot analysis show high levels of human serine racemase in areas known to contain large amounts of endogenous D-serine, such as hippocampus and corpus callosum. Robust synthesis of D-serine was detected in cells transfected with human serine racemase, demonstrating the conservation of D-amino acid metabolism in humans. Serine racemase may be a therapeutic target in psychiatric diseases as supplementation of D-serine greatly improves schizophrenia symptoms. We identify the human serine racemase genomic structure and show that the gene encompasses seven exons and localizes to chromosome 17q13.3. Identification of the intron-exon boundaries of the human serine racemase gene will be useful to search for mutations in neuropsychiatric disorders.

Trypanosoma cruzi: parasite detection and strain discrimination in chronic chagasic patients from northeastern Brazil using PCR amplification of kinetoplast DNA and nonradioactive hybridization.

Blood samples from 172 individuals from northeastern Brazil were subjected to PCR amplification of Trypanosoma cruzi-specific kDNA sequences. This method enabled us to detect parasite DNA in 21 of 47 patients that were serologically positive. In addition, 1 patient that gave doubtful results with chagasic serology was confirmed as positive by PCR. We applied the same PCR detection method to the feces of wild triatomines captured in the same region, obtaining three positive results that were confirmed by microscopic examination. The 25 amplified products obtained in this study were then reamplified with primers that gave a final amplicon containing sequences from the most variable region of kDNA minicircles. These were used as probes in hybridization experiments aimed at defining the degree of relatedness between the strains infecting humans and insects based on kDNA homologies. We found that the amplification products from the three triatomines were related and showed no cross-hybridization with those obtained from human infections. Eight amplified products from human infections showed no cross-hybridization and did not hybridize with products from other patients. This indicates that the strains of T. cruzi circulating in the region present a high level of genetic heterogeneity. Finally, a number of amplified products hybridized with amplicons that did not hybridize with each other, indicating that infections with a parasite population presenting a mixed kDNA content (either due to different strains of T. cruzi or to a hybrid parasite) are a more frequent event than previously thought.

Polymerase chain reaction detection of Trypanosoma cruzi in human blood samples as a tool for diagnosis and treatment evaluation.

Trypanosoma cruzi specific sequences were amplified by the polymerase chain reaction from total blood of human chagasic patients and normal individuals. A 330 bp fragment originating from kinetoplast DNA was specifically detected in most chagasic individuals. We tested the sensitivity and specificity of this method in normal and affected individuals attending the Evandro Chagas Hospital, Rio de Janeiro. The results of these tests were compared with serological diagnosis performed using standard techniques, and in some cases with xenodiagnosis. We found that none of the serologically negative individuals gave any specific amplification product, whereas 55 out of 61 patients previously serodiagnosed as chagasic were positive using the PCR method (sensitivity: 90%). Xenodiagnosis, which is currently considered to be the most sensitive parasitological technique for Chagas' disease diagnosis, detected only 12 out of 28 serologically positive patients (sensitivity: 43%). The usefulness of the PCR method was further investigated with chagasic patients who had received anti-parasite treatment with benznidazole. It has always been difficult to evaluate the incidence of cure in such cases by serology, since a humoral response against T. cruzi antigens may remain for years even in the absence of the parasite. We observed a positive amplification result in only 9 out of 32 treated patients who remained reactive when tested using classical serology. These observations suggest that PCR is the most sensitive technique available for direct detection of T. cruzi in chagasic patients and that it can be a very useful instrument for the follow-up of patients after specific treatment.

Foliculitis pustubulosa eosinofila: presentación de dos casos y revisión bibliográfica / Eosinophilic pustular follicullitis: report of 2 cases and bibliographic review

Se presentan dos casos de FPE, un hombre de 46 años y una mujer de 23 años, con lesiones pápulopustulosas sobre placas eritematosas, pruriginosas, localizadas en distintas áreas del cuerpo, de evolución cíclica con escasa respuesta a las terapéuticas instituidas (DAPS, corticoides). Se comparan los hallazgos de estas dos observaciones con otros casos publicados

Fibroma de la vaina tendinosa / Fibroma of the tendon sheath

Se presenta una paciente de 36 años con fibroma de la vaina tendinosa ubicado en el dedo índice de la mano derecha, de 2 x 1 x 1,5 cm. La paciente consultaba por dificultad a la flexión y tenía una evolución de 10 años. Se efectúa tratamiento quirúrgico y se obtiene un tumor duroelástico, blanquecino, multilobulado. La histopatología mostró una formación bien circunscripta, parcialmente encapsulada y constituída por lóbulos fibrohialinos donde destacan hendiduras vasculares rodeadas por colágeno denso hipocelular y con fibroblastos fusiformes cortos. No se observó recaída después de 24 meses del tratamiento quirúrgico

Foliculitis pustubulosa eosinofila: presentación de dos casos y revisión bibliográfica / Eosinophilic pustular follicullitis: report of 2 cases and bibliographic review

Se presentan dos casos de FPE, un hombre de 46 años y una mujer de 23 años, con lesiones pápulopustulosas sobre placas eritematosas, pruriginosas, localizadas en distintas áreas del cuerpo, de evolución cíclica con escasa respuesta a las terapéuticas instituidas (DAPS, corticoides). Se comparan los hallazgos de estas dos observaciones con otros casos publicados (AU)

Fibroma de la vaina tendinosa / Fibroma of the tendon sheath

Se presenta una paciente de 36 años con fibroma de la vaina tendinosa ubicado en el dedo índice de la mano derecha, de 2 x 1 x 1,5 cm. La paciente consultaba por dificultad a la flexión y tenía una evolución de 10 años. Se efectúa tratamiento quirúrgico y se obtiene un tumor duroelástico, blanquecino, multilobulado. La histopatología mostró una formación bien circunscripta, parcialmente encapsulada y constituída por lóbulos fibrohialinos donde destacan hendiduras vasculares rodeadas por colágeno denso hipocelular y con fibroblastos fusiformes cortos. No se observó recaída después de 24 meses del tratamiento quirúrgico (AU)