Irreversible EGFR Inhibitor EKB-569 Targets Low-LET γ-Radiation-Triggered Rel Orchestration and Potentiates Cell Death in Squamous Cell Carcinoma

EKB-569 (Pelitinib), an irreversible EGFR tyrosine kinase inhibitor has shown potential therapeutic efficiency in solid tumors. However, cell-killing potential in combination with radiotherapy and its underlying molecular orchestration remain to be explored. The objective of this study was to determine the effect of EKB-569 on ionizing radiation (IR)-associated NFκB-dependent cell death. SCC-4 and SCC-9 cells exposed to IR (2Gy) with and without EKB-569 treatment were analyzed for transactivation of 88 NFκB pathway molecules, NFκB DNA-binding activity, translation of the NFκB downstream mediators, Birc1, 2 and 5, cell viability, metabolic activity and apoptosis. Selective targeting of IR-induced NFκB by EKB-569 and its influence on cell-fate were assessed by overexpressing (p50/p65) and silencing (ΔIκBα) NFκB. QPCR profiling after IR exposure revealed a significant induction of 74 NFκB signal transduction molecules. Of those, 72 were suppressed with EKB-569. EMSA revealed a dose dependent inhibition of NFκB by EKB-569. More importantly, EKB-569 inhibited IR-induced NFκB in a dose-dependent manner, and this inhibition was sustained up to at least 72 h. Immunoblotting revealed a significant suppression of IR-induced Birc1, 2 and 5 by EKB-569. We observed a dose-dependent inhibition of cell viability, metabolic activity and apoptosis with EKB-569. EKB-569 significantly enhanced IR-induced cell death and apoptosis. Blocking NFκB improved IR-induced cell death. Conversely, NFκB overexpression negates EKB-569 -induced cell-killing. Together, these pre-clinical data suggest that EKB-569 is a radiosensitizer of squamous cell carcinoma and may mechanistically involve selective targeting of IR-induced NFκB-dependent survival signaling. Further pre-clinical in-vivo studies are warranted

Estuarine Clam Resources of Dakshina Kannada District

The estuarine clam resources of Netravathi-Gurupur, Mulki, Udayavara and Coondapur estuaries were estimated based on a study on the distributin of clams in space and time. T he three commercially important species were Meretrix meretrix, M. casta, and Katelysia opima

Development of novel techniques to maintain Chlorella spp. stock culture in artificial seawater

Chlorella spp. are used as feed to culture almost all species of zooplankton. Besides they form the important feed in the finfish/shell fish culture systems. Culture media such as Miquel's medium and Convey medium are conventionally used to maintain the stock culture of Chlorella spp. For the outdoor mass culture, water is enriched with groundnut oilcake, urea and super phosphate

A power-efficient thermocycler based on induction heating for DNA amplification by polymerase chain reaction

We have built a thermocycler based on the principles of induction heating for polymerase chain reaction (PCR) of target sequences in DNA samples of interest. The cycler has an average heating rate of ~0.8°C/s and a cooling rate of ~0.5°C/s, and typically takes ~4 h to complete a 40-cycle PCR protocol. It is power-efficient (~6 W per reaction tube), micro-processor controlled, and can be adapted for battery operation. Using this instrument, we have successfully amplified a 350 bp segment from a plasmid and SRY, the human sex determining gene, which occurs as a single-copy sequence in genomic DNA of human males. The PCR products from this thermocycler are comparable to those obtained by the use of commercially available machines. Its easy front-end operation, low-power design, portability and low cost makes it suitable for diagnostic field applications of PCR

Transcriptional Profiling and Deriving a Seven-Gene Signature That Discriminates Active and Latent Tuberculosis: An Integrative Bioinformatics Approach

Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (M.tb.). Our integrative analysis aims to identify the transcriptional profiling and gene expression signature that distinguish individuals with active TB (ATB) disease, and those with latent tuberculosis infection (LTBI). In the present study, we reanalyzed a microarray dataset (GSE37250) from GEO database and explored the data for differential gene expression analysis between those with ATB and LTBI derived from Malawi and South African cohorts. We used BRB array tool to distinguish DEGs (differentially expressed genes) between ATB and LTBI. Pathway enrichment analysis of DEGs was performed using DAVID bioinformatics tool. The protein–protein interaction (PPI) network of most upregulated genes was constructed using STRING analysis. We have identified 375 upregulated genes and 152 downregulated genes differentially expressed between ATB and LTBI samples commonly shared among Malawi and South African cohorts. The constructed PPI network was significantly enriched with 76 nodes connected to 151 edges. The enriched GO term/pathways were mainly related to expression of IFN stimulated genes, interleukin-1 production, and NOD-like receptor signaling pathway. Downregulated genes were significantly enriched in the Wnt signaling, B cell development, and B cell receptor signaling pathways. The short-listed DEGs were validated in a microarray data from an independent cohort (GSE19491). ROC curve analysis was done to assess the diagnostic accuracy of the gene signature in discrimination of active and latent tuberculosis. Thus, we have derived a seven-gene signature, which included five upregulated genes FCGR1B, ANKRD22, CARD17, IFITM3, TNFAIP6 and two downregulated genes FCGBP and KLF12, as a biomarker for discrimination of active and latent tuberculosis. The identified genes have a sensitivity of 80–100% and specificity of 80–95%. Area under the curve (AUC) value of the genes ranged from 0.84 to 1. This seven-gene signature has a high diagnostic accuracy in discrimination of active and latent tuberculosis

Plasma chemokines are biomarkers of disease severity, higher bacterial burden and delayed sputum culture conversion in pulmonary tuberculosis

Plasma cytokines are biomarkers of disease extent and mycobacterial burden in pulmonary tuberculosis (PTB). Whether chemokines can perform the same role in PTB is not known. We examined the plasma levels of chemokines in individuals with PTB, latent TB (LTB) or healthy controls (HC) and their association with disease severity and mycobacterial burdens in PTB. We also examined the chemokines in PTB individuals at the end of anti-tuberculous chemotherapy (ATT). PTB individuals exhibited significantly higher levels of CCL1, CCL3, CXCL1, CXCL2, CXCL9 and CXCL10 in comparison to LTB and/or HC individuals. PTB individuals with bilateral or cavitary disease displayed significantly elevated levels of CCL1, CCL3, CXCL1, CXCL10 and CXCL11 compared to those with unilateral or non-cavitary disease and also exhibited a significant positive relationship with bacterial burdens. In addition, PTB individuals with slower culture conversion displayed significantly elevated levels of CCL1, CCL3, CXCL1 and CXCL9 at the time of PTB diagnosis and prior to ATT. Finally, the chemokines were significantly reduced following successful ATT. Our data demonstrate that PTB is associated with elevated levels of chemokines, which are partially reversed followed chemotherapy. Our data demonstrate that chemokines are markers of disease severity, predicting increased bacterial burden and delayed culture conversion in PTB

(E)-1,1,4,4-Tetra­phenyl­but-2-yne-1,4-diol

The mol­ecule of the title compound, C28H22O2, is centrosymmetric with the inversion centre located at the mid-point of the C C bond [1.178 (5) Å]. The hydroxyl groups therefore lie on either side of the mol­ecule. The crystal structure is stabilized by O—H⋯O hydrogen bonds, leading to the formation of a linear supra­molecular chain along the b axis

Identification and Characterization of Genetic Determinants of Isoniazid and Rifampicin Resistance in Mycobacterium tuberculosis in Southern India

Abstract: Drug-resistant tuberculosis (TB), one of the leading causes of death worldwide, arises mainly from spontaneous mutations in the genome of Mycobacterium tuberculosis. There is an urgent need to understand the mechanisms by which the mutations confer resistance in order to identify new drug targets and to design new drugs. Previous studies have reported numerous mutations that confer resistance to anti-TB drugs, but there has been little systematic analysis to understand their genetic background and the potential impacts on the drug target stability and/or interactions. Here, we report the analysis of whole-genome sequence data for 98 clinical M. tuberculosis isolates from a city in southern India. The collection was screened for phenotypic resistance and sequenced to mine the genetic mutations conferring resistance to isoniazid and rifampicin. The most frequent mutation among isoniazid and rifampicin isolates was S315T in katG and S450L in rpoB respectively. The impacts of mutations on protein stability, protein-protein interactions and protein-ligand interactions were analysed using both statistical and machine-learning approaches. Drug-resistant mutations were predicted not only to target active sites in an orthosteric manner, but also to act through allosteric mechanisms arising from distant sites, sometimes at the protein-protein interface