Cytomegalovirus Disease in Renal Transplant Recipients: A Single-Center Experience

Cytomegalovirus (CMV) is the most common viral infection following kidney transplant, has been recognized as a major factor for graft loss and increased incidence of acute rejection. Different studies have reported a variable incidence of CMV disease with the use of Mycophenolate mofetil (MMF). We retrospectively analyzed our renal transplant recipients to review the results of CMV disease and to compare CMV disease in patient on Azathioprine and MMF for this purpose we retrospectively reviewed 521 live related kidney transplant recipients at our institute. 74 (14.2 %) live related allograft recipients developed CMV disease after a median interval of 7.18 ± 4.35 months from transplantation. The mean age was 36.15 ± 10.7 years. 63 of the patients were male. Malaise, fever and diarrhea were among most common symptoms. 20 (27.02 %) of the 74 recipients developed transaminitis, 13 (17.2 %) developed CMV gastritis, 5 (9.13 %) recipients developed pneumonia, and 3 (4.05 %) patient developed colitis. 59 (80 %) patients had leucopenia and 41 (56.5 %) developed thrombocytopenia. Mean serum creatinine level was 1.5 ± 0.4 (0.9–2.4) mg/dl before the disease, 1.9 ± 0.6 (1.3–3.6) mg/dl at the time of the diagnosis, and 1.7 ± 0.06 (0.8–4.2) mg/dl at the end of the treatment. CMV disease developed in 9 (36 %) of recipients who received basiliximab as induction therapy and 13 (30.24 %) of recipients who received ATG (p > 0.05). The incidence of CMV disease was similar in cyclosporine based regimen (13.2 %) and Tacrolimus based regimen 27 (16.16 %) (p = 0.137) and was also similar in Azathioprine 41 (9.5 %) and MMF group 33 (14.3 %) (p = 0.163). There was no significant difference in severity of CMV disease in both groups, except a higher incidence of leucopenia in Azathioprine group (86 vs. 74 %, p < 0.05) as compared to MMF group. 51 (68.91 %) patient developed graft dysfunction during CMV disease. In conclusion we report a low incidence (14.2 %) and milder form of cytomegalovirus disease at our center. Use of universal cytomegalovirus prophylaxis was associated with a low incidence and milder form of the disease. Incidence of CMV disease was similar between Azathioprine and MMF groups.     

Comparative structural analysis of two proteins belonging to quorum sensing system in Vibrio cholerae

Vibrio cholerae uses quorum sensing communication system to interact with other bacteria and for gauzing environmental parameters. This organism dwells equally well in both human host and aquatic environments. Quorum sensing regulates multitude of activities and is one of the lucrative targets presently pursued for drug design in bacteria to encounter virulence. Histidine phosphotransfer protein LuxU and response regulator LuxO of V. cholerae are known to play important roles in biofilms and virulence machinery. In the present study, we used computational methods to model LuxU and LuxO and simulated the interactions of LuxO and LuxU. Since no structural details of the proteins were available, we employed homology modeling to construct the three-dimensional structures and then performed molecular dynamics simulations to study dynamic behavior of the LuxO and LuxU from V. cholerae. The modeled proteins were validated and subjected to molecular docking analyses. This allowed us to predict the binding modes of the proteins to elucidate probable sites of interference.     

Rare de novo germline copy-number variation in testicular cancer

Although heritable factors are an important determinant of risk of early-onset cancer, the majority of these malignancies appear to occur sporadically without identifiable risk factors. Germline de novo copy-number variations (CNVs) have been observed in sporadic neurocognitive and cardiovascular disorders. We explored this mechanism in 382 genomes of 116 early-onset cancer case-parent trios and unaffected siblings. Unique de novo germline CNVs were not observed in 107 breast or colon cancer trios or controls but were indeed found in 7% of 43 testicular germ cell tumor trios; this percentage exceeds background CNV rates and suggests a rare de novo genetic paradigm for susceptibility to some human malignancies.     

GANGLIOSIDE PATTERNS AND PHENOTYPIC CHARACTERISTICS IN A NORMAL VARIANT AND A TRANSFORMED BACK VARIANT OF A SIMIAN VIRUS 40-INDUCED HAMSTER TUMOR CELL LINE

Ganglioside patterns of a cloned Simian virus 40- (SV40) induced hamster tumor cell (Cl₂TSV₅-S), its normal variant (Cl₂TSV₅-R) which are Cl₂TSV₅-S gradually adapted to grow in the presence of 2 µg/ml actinomycin D and exhibit certain normal phenotypic characteristics, and its back variant (Cl₂TSV₅-RR), which are Cl₂TSV₅-R cells grown in the absence of actinomycin D for more than 60 passages and which exhibit greater phenotypic similarity to Cl₂TSV₅-S cells, have been analyzed. All three cell lines contain N(acetylneuraminyl) galactosylglycosyl ceramide (hematoside, GM₃), N-acetylgalactosaminyl (N-acetylneuraminyl) galactosylglucosyl ceramide (GM₂), and a higher ganglioside tentatively identified as disialohematoside. However, Cl₂TSV₅-R have more GM₂ than Cl₂TSV₅-S whereas Cl₂TSV₅-RR contain an intermediate amount of GM₂. The amount of GM₂ is correlative with the activity of UDP-N-acetylgalactosamine: hematoside N-acetylgalactosaminyl transferase in the extract of the three cell lines and with their agglutination by wheat germ agglutinin.     

Empirical model and in vivo characterization of the bacterial response to synthetic gene expression show that ribosome allocation limits growth rate

Synthetic biology uses modeling to facilitate the design of new genetic constructions. In particular, it is of utmost importance to model the reaction of the cellular chassis when expressing heterologous systems. We constructed a mathematical model for the response of a bacterial cell chassis under heterologous expression. For this, we relied on previous characterization of the growth-rate dependence on cellular resource availability (in this case, DNA and RNA polymerases and ribosomes). Accordingly, we estimated the maximum capacities of the cell for heterologous expression to be 46% of the total RNA and the 33% of the total protein. To experimentally validate our model, we engineered two genetic constructions that involved the constitutive expression of a fluorescent reporter in a vector with a tunable origin of replication. We performed fluorescent measurements using population and single-cell fluorescent measurements. Our model predicted cell growth for several heterologous constructions under five different culture conditions and various plasmid copy numbers with significant accuracy, and confirmed that ribosomes act as the limiting resource. Our study also confirmed that the bacterial response to synthetic gene expression could be understood in terms of the requirement for cellular resources and could be predicted from relevant cellular parameters.     

Tissue-Specific Enrichment of Lymphoma Risk Loci in Regulatory Elements

Though numerous polymorphisms have been associated with risk of developing lymphoma, how these variants function to promote tumorigenesis is poorly understood. Here, we report that lymphoma risk SNPs, especially in the non-Hodgkin’s lymphoma subtype chronic lymphocytic leukemia, are significantly enriched for co-localization with epigenetic marks of active gene regulation. These enrichments were seen in a lymphoid-specific manner for numerous ENCODE datasets, including DNase-hypersensitivity as well as multiple segmentation-defined enhancer regions. Furthermore, we identify putatively functional SNPs that are both in regulatory elements in lymphocytes and are associated with gene expression changes in blood. We developed an algorithm, UES, that uses a Monte Carlo simulation approach to calculate the enrichment of previously identified risk SNPs in various functional elements. This multiscale approach integrating multiple datasets helps disentangle the underlying biology of lymphoma, and more broadly, is generally applicable to GWAS results from other diseases as well.     

The Chromone Alkaloid,Rohitukine, Affords Anti-Cancer Activity via Modulating Apoptosis Pathways in A549 Cell Line and Yeast Mitogen Activated Protein Kinase (MAPK) Pathway

The field of cancer research and treatment has made significant progress, yet we are far from having completely safe, efficient and specific therapies that target cancer cells and spare the healthy tissues. Natural compounds may reduce the problems related to cancer treatment. Currently, many plant products are being used to treat cancer. In this study, Rohitukine, a natural occurring chromone alkaloid extracted from Dysoxylum binectariferum, was investigated for cytotoxic properties against budding yeast as well as against lung cancer (A549) cells. We endeavored to specifically study Rohitukine in S. cerevisiae in the context of MAPK pathways as yeast probably represents the experimental model where the organization and regulation of MAPK pathways are best understood. MAPK are evolutionarily conserved protein kinases that transfer extracellular signals to the machinery controlling essential cellular processes like growth, migration, differentiation, cell division and apoptosis. We aimed at carrying out hypothesis driven studies towards targeting the important network of cellular communication, a critical process that gets awry in cancer. Employing mutant strains of genetic model system Saccharomyces cerevisiae. S. cerevisiae encodes five MAPKs involved in control of distinct cellular responses such as growth, differentiation, migration and apoptosis. Our study involves gene knockouts of Slt2 and Hog1 which are functional homologs of human ERK5 and mammalian p38 MAPK, respectively. We performed cytotoxicity assay to evaluate the effect of Rohitukine on cell viability and also determined the effects of drug on generation of reactive oxygen species, induction of apoptosis and expression of Slt2 and Hog1 gene at mRNA level in the presence of drug. The results of this study show a differential effect in the activity of drug between the WT, Slt2 and Hog1 gene deletion strain indicating involvement of MAPK pathway. Further, we investigated Rohitukine induced cytotoxic effects in lung cancer cells and stimulated the productions of ROS after exposure for 24 hrs. Results from western blotting suggest that Rohitukine triggered apoptosis in A549 cell line through upregulation of p53, caspase9 and down regulation of Bcl-2 protein. The scope of this study is to understand the mechanism of anticancer activity of Rohitukine to increase the repertoire of anticancer drugs, so that problem created by emergence of resistance towards standard anticancer compounds can be alleviated.     

Synthesis of Some New Fluorine Containing 2-(N-Arylamino)/2-methyl-4-aryl Thiazoles and Their Bactericidal Activity

Sixteen fluorine containing 2-(N-arylamino)/2-methyl-4-aryl thiazoles have been synthesised and characterized by spectral (IR and NMR) studies. Some representative compounds have also been screened for their bactericidal activity.