Gut Microbiota-Produced Tryptamine Activates an Epithelial G-Protein-Coupled Receptor to Increase Colonic Secretion

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Molecular profiling of mucosal tissue associated microbiota in patients manifesting acute exacerbations and remission stage of ulcerative colitis

Dysbiosis of intestinal microflora has been postulated in ulcerative colitis (UC), which is characterized by imbalance of mucosal tissue associated bacterial communities. However, the specific changes in mucosal microflora during different stages of UC are still unknown. The aim of the current study was to investigate the changes in mucosal tissue associated microbiota during acute exacerbations and remission stages of UC. The mucosal microbiota associated with colon biopsy of 12 patients suffering from UC (exacerbated stage) and the follow-up samples from the same patients (remission stage) as well as non-IBD subjects was studied using 16S rRNA gene-based sequencing and quantitative PCR. The total bacterial count in patients suffering from exacerbated phase of UC was observed to be two fold lower compared to that of the non-IBD subjects (p?=?0.0049, Wilcox on matched-pairs signed rank tests). Bacterial genera including Stenotrophomonas, Parabacteroides, Elizabethkingia, Pseudomonas, Micrococcus, Ochrobactrum and Achromobacter were significantly higher in abundance during exacerbated phase of UC as compared to remission phase. The alterations in bacterial diversity with an increase in the abnormal microbial communities signify the extent of dysbiosis in mucosal microbiota in patients suffering from UC. Our study helps in identifying the specific genera dominating the microbiota during the disease and thus lays a basis for further investigation of the possible role of these bacteria in pathogenesis of UC.     

Synthesis of aminopyrazole analogs and their evaluation as CDK inhibitors for cancer therapy

We synthesized a library of aminopyrazole analogs to systematically explore the hydrophobic pocket adjacent to the hinge region and the solvent exposed region of cyclin dependent kinases. Structure-activity relationship studies identified an optimal substitution for the hydrophobic pocket and analog 24 as a potent and selective CDK2/5 inhibitor.     

Synthesis of enamino-2-oxindoles via conjugate addition between α-azido ketones and 3-alkenyl oxindoles: Cytotoxicity evaluation and apoptosis inducing studies

A facile method for the construction of double bond between 3-ylidene oxindoles and α-azido ketones has been successfully accomplished with a mild base. This method features azido reduction with concomitant double bond formation to provide the new class of bioactive enamino-2-oxindoles. These new compounds were screened for their in vitro cytotoxic potential on selected human cancer cell lines such as colon, lung, breast, and cervical cancer cells. Among them, representative compounds 3a, 3h, 3k, 3p, 3w and 3x showed notable cytotoxicity profile with IC₅₀ values ranging from 1.40?±?0.10 to 28.7?±?0.36?µM. Compound 3k displayed most potent cytotoxicity against lung cancer (NCI-H460) cells with an IC₅₀ value of 1.40?±?0.10?µM. 3k also arrested the G2/M phase of the cell cycle and induced distinctive apoptotic features on lung cancer cells. The apoptosis induction is supported by various cellular assays such as AO/EB, DAPI, and DCFDA staining studies including clonogenic assay. Extent of apoptosis was also analyzed by Annexin binding and JC-1 staining. Moreover, this method is amenable for the generation of a library of new class of stable bioactive enamino-2-oxindoles.     

Mossambicus tilapia (<Emphasis Type="Italic">Oreochromis mossambicus</Emphasis>) collected from water bodies impacted by urban waste carries extended-spectrum beta-lactamases and integron-bearing gut bacteria

Oreochromis mossambicus (Peters 1852) (Tilapia) is one of the most consumed fish globally. Tilapia thrives well in environments polluted by urban waste, which invariably contain antibiotic-resistant bacteria and antibiotic resistance genes (ARGs). Thus, Tilapia surviving in such polluted environments may serve as a potential source for dissemination of ARGs. To investigate this, we isolated bacterial strains from gut of Tilapia found in polluted rivers and lakes near Pune, India, and studied the prevalence of resistance genes by molecular methods. A total of 91 bacterial strains were obtained, which include fish pathogens and human pathogens such as Aeromonas hydrophila, Klebsiella pneumoniae, E. coli, Serratia marcescens, Enterobacter spp. and Shigella spp. Overall the prevalence of class 1 integrons, class 2 integrons, extended-spectrum beta-lactamases (ESBLs) bla _CTX-M, bla _SHV and aac(6')-Ib-cr gene was 38%, 24%, 38%, 31% and 31% respectively. Forty-two percent of the Enterobacteriaceae strains carried bla _CTX-M gene, which is a common ESBL gene in clinics. The study demonstrates that tilapia found in the polluted waters can serve as reservoirs and an alternative route for human exposure to clinically important ARG-carrying bacteria. The consumption and handling of these fish may pose a potential health risk.     

Molecular interaction of selected phytochemicals under the charged environment of Plasmodium falciparum chloroquine resistance transporter (PfCRT) model

Phytochemicals of Catharanthus roseus Linn. and Tylophora indica have been known for their inhibition of malarial parasite, Plasmodium falciparum in cell culture. Resistance to chloroquine (CQ), a widely used antimalarial drug, is due to the CQ resistance transporter (CRT) system. The present study deals with computational modeling of Plasmodium falciparum chloroquine resistance transporter (PfCRT) protein and development of charged environment to mimic a condition of resistance. The model of PfCRT was developed using Protein homology/analogy engine (PHYRE ver 0.2) and was validated based on the results obtained using PSI-PRED. Subsequently, molecular interactions of selected phytochemicals extracted from C. roseus Linn. and T. indica were studied using multiple-iterated genetic algorithm-based docking protocol in order to investigate the translocation of these legends across the PfCRT protein. Further, molecular dynamics studies exhibiting interaction energy estimates of these compounds within the active site of the protein showed that compounds are more selective toward PfCRT. Clusters of conformations with the free energy of binding were estimated which clearly demonstrated the potential channel and by this means the translocation across the PfCRT is anticipated.     

Continuing to Confront COPD International Patient Survey: Economic Impact of COPD in 12 Countries

BackgroundThe Continuing to Confront COPD International Patient Survey estimated the prevalence and burden of COPD across 12 countries. Using data from this survey we evaluated the economic impact of COPD.MethodsThis cross-sectional, population-based survey questioned 4,343 subjects aged 40 years and older, fulfilling a case definition of COPD based on self-reported physician diagnosis or symptomatology. Direct cost measures were based on exacerbations of COPD (treated and those requiring emergency department visits and/or hospitalisation), contacts with healthcare professionals, and COPD medications. Indirect costs were calculated from work loss values using the Work Productivity and Activity Impairment scale. Combined direct and indirect costs estimated the total societal costs per patient.ResultsThe annual direct costs of COPD ranged from $504 (South Korea) to $9,981 (USA), with inpatient hospitalisations (5 countries) and home oxygen therapy (3 countries) being the key drivers of direct costs. The proportion of patients completely prevented from working due to their COPD ranged from 6% (Italy) to 52% (USA and UK) with 8 countries reporting this to be ≥20%. Total societal costs per patient varied widely from $1,721 (Russia) to $30,826 (USA) but a consistent pattern across countries showed greater costs among those with increased burden of COPD (symptoms, health status and more severe disease) and a greater number of comorbidities.ConclusionsThe economic burden of COPD is considerable across countries, and requires targeted resources to optimise COPD management encompassing the control of symptoms, prevention of exacerbations and effective treatment of comorbidities. Strategies to allow COPD patients to remain in work are important for addressing the substantial wider societal costs.     

Further Optimization of Detritylation in Solid-Phase Oligodeoxyribonucleotide Synthesis

Various conditions for optimum detritylation (i.e., the removal of 5′-O-trityl protecting groups) during solid-phase synthesis of oligodeoxyribonucleotides were investigated. Di- and tri-chloroacetic acids of variable concentrations were used to study the removal of the 4,4′-dimethoxytrityl (DMTr) group. It was found that the DMTr group could be completely removed under much milder acidic conditions than what are currently used for automated solid-phase synthesis. The 2,7-dimethylpixyl (DMPx) is proposed as an alternative and more readily removable group for the protection of the 5′-OH functions both in solid- and solution-phase synthesis. The improved detritylation conditions are expected to minimize the waste and offer a protocol for incorporation of acid sensitive building-blocks in oligonucleotides.