Conventional renal cell carcinoma with renal capsular leiomyoma: A diagnostic dilemma.

Primary renal leiomyomas are very rare benign tumors of the kidney, arising from smooth muscle cells of the renal capsule, pelvis or blood vessels. Simultaneous occurrence of a leiomyoma with conventional renal cell carcinoma (RCC) in the same kidney is an extremely rare incidence. Herein we describe a case, which to the best of our knowledge is the second reported case in the English literature. This 70-year-old female presented in surgical out-patient department with the complaints of hematuria and abdominal pain. Subsequently, on computed tomography a multifocal mass was noted in the right kidney, measuring 4.5 cm × 3 cm × 2 cm and 1 cm × 0.5 cm × 0.5 cm respectively. A radical nephrectomy was performed with the clinical diagnosis of a multifocal RCC. Histopathological examination revealed a conventional RCC in the larger nodule, whereas the smaller nodule showed a sub capsular leiomyoma, which was immune-positive for smooth muscle actin and HMB45. In the index case, radiology could not differentiate between the RCC and leiomyoma. Apart from being a radiological diagnostic dilemma, rare HMB45 immunostain positivity in capsular leiomyoma may create diagnostic dilemma for histopathologists too. Sole HMB45 positivity should not distract one to diagnose this lesion as an angiomyolipoma, unless the other components are seen.

Study of water supply & sanitation practices in India using geographic information systems: Some design & other considerations in a village setting.

Background & objectives: Availability of clean water and adequate sanitation facilities are of prime importance for limiting diarrhoeal diseases. We examined the water and sanitation facilities of a village in southern India using geographic information system (GIS) tools. Methods: Places of residence, water storage and distribution, sewage and places where people in the village defaecated were mapped and drinking water sources were tested for microbial contamination in Nelvoy village, Vellore district, Tamil Nadu. Results: Water in the village was found to be microbiologically unfit for consumption. Analysis using direct observations supplemented by GIS maps revealed poor planning, poor engineering design and lack of policing of the water distribution system causing possible contamination of drinking water from sewage at multiple sites. Interpretation & conclusions: Until appropriate engineering designs for water supply and sewage disposal to suit individual village needs are made available, point-of-use water disinfection methods could serve as an interim solution.

Three-dimensional structure of heat shock protein 90 from Plasmodium falciparum: molecular modelling approach to rational drug design against malaria.

We have recently implicated heat shock protein 90 from Plasmodium falciparum (PfHsp90) as a potential drug target against malaria. Using inhibitors specific to the nucleotide binding domain of Hsp90, we have shown potent growth inhibitory effects on development of malarial parasite in human erythrocytes. To gain better understanding of the vital role played by PfHsp90 in parasite growth,we have modeled its three dimensional structure using recently described full length structure of yeast Hsp90.S equence similarity found between PfHsp90 and yeast Hsp90 allowed us to model the core structure with high confidence. The superimposition of the predicted structure with that of the template yeast Hsp90 structure reveals an RMSD of 3.31 Angstrom. The N-terminal and middle domains showed the least RMSD (1.76 Angstrom) while the more divergent C-terminus showed a greater RMSD (2.84 Angstrom) with respect to the template. The structure shows overall conservation of domains involved in nucleotide binding, ATPase activity, co-chaperone binding as well as inter-subunit interactions. Important co-chaperones known to modulate Hsp90 function in other eukaryotes are conserved in malarial parasite as well. An acidic stretch of amino acids found in the linker region, which is uniquely extended in PfHsp90 could not be modeled in this structure suggesting a flexible conformation. Our results provide a basis to compare the overall structure and functional pathways dependent on PfHsp90 in malarial parasite. Further analysis of differences found between human and parasite Hsp90 may make it possible to design inhibitors targeted specifically against malaria.