HIV type 1 sequence diversity and dual infections in Kenya

As vertical transmission of HIV-1 is an ongoing problem in East Africa, we analyzed HIV-1 strains of infected mothers, from Kisumu, Kenya. We sequenced the gag and gp120 regions from peripheral blood mononuclear cells (PBMC) of 15 HIV-infected mothers attending an antenatal clinic. PCR, cloning, bootscanning, using the program Simplot, and phylogenetic analyses were conducted to assign subtypes and identify recombinants. Our analyses showed two dual infections from patients who had infections with pure subtypes and recombinants subtype D. In addition, we also noted the presence of subsubtype A1 and A2, as well as unique recombinants in this area. These results imply that the HIV epidemic in western Kenya is a dynamic one and is continually evolving. Therefore, continued monitoring of the epidemic in this region is necessary if a vaccine for the area is to be developed.     

Effect of vitamin D administration during pregnancy on neonatal growth in the rat

Groups of rats on commercial diet were injected 3,000 IU (group 2) and 7,500 IU (group 3) of vitamin D3 on the 10th day of pregnancy. Compared to control pups (group 1), the pups in group 2 and 3 weighed significantly more on the 10th, 20th and 28th day of age. At 28th day of age, study of the gastrocnemius muscle revealed significantly greater organ weight, protein, DNA and RNA contents, protein/DNA and RNA/DNA ratios in group 2 and 3 pups than in controls. In the liver, whereas all these indices were significantly increased in group 3 pups, only protein/DNA and RNA/DNA ratios were significantly increased in group 2 pups. Brain weight, its RNA content and RNA/DNA ratio were significantly greater in group 2 and 3 pups than in controls. The results suggest that vitamin D administration in pregnancy promotes soft tissue growth in the pups by enhancing cellular proliferation and hypertrophy.     

Comparative Evaluation of PCR and Imprint Smear Microscopy Analyses of Skin Biopsy Specimens in Diagnosis of Macular,Papular, and Mixed Papulo-Nodular Lesions of Post-Kala-Azar Dermal Leishmaniasis

Diagnosis of post-kala-azar dermal leishmaniasis (PKDL), particularly the macular form, is difficult when based on microscopy. This study compared the results of nested PCR (91.9% positive samples) with imprint smear microscopy (70.9% positive samples) for 62 PKDL samples. We found that nested PCR, which indicated 87.5% positivity for the macular lesions, compared to 41.6% positivity by imprint smear microscopy, is an efficient method for early diagnosis of PKDL.     

Role of carbonic anhydrase IX, α-methylacyl coenzyme a racemase,cytokeratin 7, and galectin-3 in the evaluation of renal neoplasms: a tissue microarray immunohistochemical study

Kidney tumors of various types may behave differently and have different prognosis. Because of some overlapping morphological features and immunohistochemical staining pattern, they may pose diagnostic challenge. Therefore, it is necessary to explore additional immunohistochemical stains to help classifying these epithelial neoplasms. Tissue microarrays of 20 cases each of renal cell carcinomas of clear cell, chromophobe, and papillary variants and oncocytoma were constructed and used to test a panel of immunohistochemical markers including carbonic anhydrase IX, galectin-3, cytokeratin 7 (CK7), and α-methylacyl coenzyme a racemase. Carbonic anhydrase IX was highly sensitive for clear cell renal cell carcinoma (90% positivity) and was negative in all other renal epithelial tumors except for 1 chromophobe renal cell carcinoma (chRCC). Expression of galectin-3 was found mostly in renal tumors with oncocytic features, including oncocytomas (100%) and chRCCs (89%). α-Methylacyl coenzyme a racemase was positive in papillary renal cell carcinoma (100%). CK7 was positive in papillary renal cell carcinoma (90%), chRCC (89%), and oncocytoma (90%). Although both chRCC and oncocytoma were positive for CK7, but with a different patterns, CK7 staining in chRCC was diffuse, whereas it was sporadic in oncocytoma. Panel of carbonic anhydrase IX, galectin-3, CK7, and α-methylacyl coenzyme a racemase is sensitive and specific for the differential diagnosis of the renal epithelial tumors.     

Identification of potential inhibitors of Zika virus NS5 RNA-dependent RNA polymerase through virtual screening and molecular dynamic simulations

Zika virus (ZIKV) is one of the mosquito borne flavivirus with several outbreaks in past few years in tropical and subtropical regions. The non-structural proteins of flaviviruses are suitable active targets for inhibitory drugs due to their role in pathogenicity. In ZIKV, the non-structural protein 5 (NS5) RNA-Dependent RNA polymerase replicates its genome. Here we have performed virtual screening to identify suitable ligands that can potentially halt the ZIKV NS5 RNA dependent RNA polymerase (RdRp). During this process, we searched and screened a library of ligands against ZIKV NS5 RdRp. The selected ligands with significant binding energy and ligand-receptor interactions were further processed. Among the selected docked conformations, top five was further optimized at atomic level using molecular dynamic simulations followed by binding free energy calculations. The interactions of ligands with the target structure of ZIKV RdRp revealed that they form strong bonds within the active sites of the receptor molecule. The efficacy of these drugs against ZIKV can be further analyzed through in-vitro and in-vivo studies.     

Evidence for clonal propagation in natural isolates of Plasmodium falciparum from Venezuela

We have analyzed 75 isolates of Plasmodium falciparum, collected in Venezuela during both the dry (November) and rainy (May-July) seasons, with a range of genetic markers including antigen genes and 14 random amplified polymorphic DNA (RAPD) primers. Thirteen P. falciparum stocks from Kenya and four other Plasmodium species are included in the analysis for comparison. Cross-hybridization shows that the 14 RAPD primers reveal 14 separate regions of the parasite's genome. The P. falciparum isolates are a monophyletic clade, significantly different from the other Plasmodium species. We identify three RAPD characters that could be useful as "tags" for rapid species identification. The Venezuelan genotypes fall into two discrete genetic subdivisions associated with either the dry or the rainy season; the isolates collected in the rainy season exhibit greater genetic diversity. There is significant linkage disequilibrium in each seasonal subsample and in the full sample. In contrast, no linkage disequilibrium is detected in the African sample. These results support the hypothesis that the population structure of P. falciparum in Venezuela, but not in Africa, is predominantly clonal. However, the impact of genetic recombination on Venezuelan P. falciparum seems higher than in parasitic species with long-term clonal evolution like Trypanosoma cruzi, the agent of Chagas' disease. The genetic structure of the Venezuelan samples is similar to that of Escherichia coli, a bacterium that propagates clonally, with occasional genetic recombination.     

Breeding ecology of visceral leishmaniasis vector sandfly in Bihar state of India

Soil samples weighing 255.3 kg, collected from 50 villages of 5 visceral leishmaniasis (VL) endemic districts of Bihar state were examined for sandfly breeding, using the soil incubation method. Breeding of sandflies was detected in 46% of the villages and 7.3% of the soil samples examined. Intra-domestic soil was found to be infested with 2 species of sandflies, Phlebotomus argentipes Annandale and Brunetti and Phlebotomus papatasi (Scopoli). In comparison with human houses, P. argentipes was found to show greater propensity to breed in cattle sheds; breeding prevalences in villages and soil samples, for the species, were significantly higher in cattle sheds than in human houses. The preference for breeding sites by the sandflies appeared to be associated with the pH of the soil. P. argentipes thus preferred to breed in the alkaline soil of cattle shed, and P. papatasi in the soil with neutral pH, of human houses. The emergence of adult P. argentipes from soil samples was mainly observed from April to October.