The influence of human papillomavirus type and HIV status on the lymphomononuclear cell profile in patients with cervical intraepithelial lesions of different severity

Abstract Background Immunological alterations are implicated in the increased prevalence of high-grade squamous intraepithelial lesions (HG-SIL) and persistent human papillomavirus (HPV) infection. This study evaluated the expression of CD4, CD8, CD25 (IL-2Rα) and CD28 antigens from SIL biopsies, stratified by HIV status and HPV-type. Biopsies specimens from 82 (35 HIV+) women with a normal cervix, low-grade (LG-SIL) or high-grade lesions (HG-SIL) were studied. CD molecule expression was evaluated by immunohistochemistry and HPV detection/typing performed using PCR techniques. Results CD4 stromal staining was increased in patients with HPV18. Women with HPV16 infection showed decreased: a) CD8 and CD25 stromal staining, b) CD25 staining in LG-SIL epithelium and in HG-SIL stroma. In HIV- women samples, CD28 epithelial staining and CD8 stromal staining surrounding metaplastic epithelium were less intense and even absent, as compared to HIV+ women. Both epithelial and stromal CD8 staining was more intense in the HG-SIL/HIV+ group than in the HG-SIL/HIV- group. Positive correlations were observed between CD4/CD25, CD4/CD28 and CD25/CD28 in the stroma and CD25/CD28 in the epithelium. Conclusion HIV status and HPV-type may influence the lymphomononuclear cell profile present in the spectrum of cervical lesions. The knowledge of the infiltrating cell profile in cervical tumours may help the development of specific anti-tumoural strategies.

Complete ¹H and 13C NMR structural assignments for a group of four goyazensolide-type furanoheliangolides

Four goyazensolide-type sesquiterpene lactones - lychnofolide, centratherin, goyazensolide and goyazensolide acetate - were thoroughly studied by NMR experimental techniques. ¹H NMR, 13C NMR {¹H}, COSY, HMQC, HMBC, J-res. and NOE experiments were performed to provide the needed structural information. Complete and unequivocal assignment, including the determination of all multiplicities, was obtained for each structure and the data collections are presented in tables.

Worldwide spread of Dengue virus type 1

BACKGROUND: DENV-1 is one of the four viral serotypes that causes Dengue, the most common mosquito-borne viral disease of humans. The prevalence of these viruses has grown in recent decades and is now present in more than 100 countries. Limited studies document the spread of DENV-1 over the world despite its importance for human health. METHODOLOGY/PRINCIPAL FINDINGS: We used representative DENV-1 envelope gene sequences to unravel the dynamics of viral diffusion under a Bayesian phylogeographic approach. Data included strains from 45 distinct geographic locations isolated from 1944 to 2009. The estimated mean rate of nucleotide substitution was 6.56 × 10⁻⁴ substitutions/site/year. The larger genotypes (I, IV and V) had a distinctive phylogenetic structure and since 1990 they experienced effective population size oscillations. Thailand and Indonesia represented the main sources of strains for neighboring countries. Besides, Asia broadcast lineages into the Americas and the Pacific region that diverged in isolation. Also, a transmission network analysis revealed the pivotal role of Indochina in the global diffusion of DENV-1 and of the Caribbean in the diffusion over the Americas. CONCLUSIONS/SIGNIFICANCE: The study summarizes the spatiotemporal DENV-1 worldwide spread that may help disease control.

Genomic mosaicism in two strains of Dengue virus type 3

Recombination is a significant factor driving genomic evolution, but it is not well understood in Dengue virus. We used phylogenetic methods to search for recombination in 636 Dengue virus type 3 (DENV-3) genomes and unveiled complex recombination patterns in two strains, which appear to be the outcome of recombination between genotype II and genotype I parental DENV-3 lineages. Our findings of genomic mosaic structures suggest that strand switching during RNA synthesis may be involved in the generation of genetic diversity in dengue viruses.