Digoxin Suppresses Pyruvate Kinase M2-Promoted HIF-1α Transactivation in Steatohepatitis

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Biological and computational studies provide insights into Caesalphinia digyna Rottler stems

Caesalpinia digyna (Rottl.) (Family: Fabaceae) is an essential medicinal plant for it's conventional uses against a kind of human disorders. This research aims to investigate the antidiarrheal, antibacterial and antifungal properties of the methanol extract of the stems extracts of the C. digyna (MECD). The in vivo antidiarrheal activity of the stem extracts were evaluated by using castor oil-induced diarrhea, castor oil-induced enteropooling and charcoal induced intestinal transit in mice model. Besides, in vitro antimicrobial potentiality of MECD was investigated by the disc diffusion method. In silico activity of the isolated compounds were performed by Schrödinger-Maestro (Version 11.1) software. In addition, The ADME/T analysis and PASS prediction were implemented by using pass online tools. In the antidiarrheal investigation, the MECD exhibited a notable inhibition rate in all test approaches which were statistically significant (p < 0.05, p < 0.1, p < 0.01). MECD 400 mg/kg showed the maximum antidiarrheal potency in all the test methods. In vitro antimicrobial analysis unveiled that, MECD revealed higher potentiality against almost all pathogens and indicates dose-dependent activity against almost all the bacteria and fungi. In the case of in silico evaluation of anti-diarrheal, anti-bacterial and anti-fungal activity, all three isolated compounds met the pre-conditions of Lipinski's five rules for drug discovery. Pass predicted study also employed for all compounds. However, The chemical constituents of the C. digyna can be a potent source of anti-diarrheal, anti-bacterial and anti-fungal medicine and further modification and simulation studies are required to establish the effectiveness of bioactive compounds.     

Antimicrobial Resistance,Virulence Factors and Genetic Diversity of Escherichia coli Isolates from Household Water Supply in Dhaka,Bangladesh

Background

Unsafe water supplies continue to raise public health concerns, especially in urban areas in low resource countries. To understand the extent of public health risk attributed to supply water in Dhaka city, Bangladesh, Escherichia coli isolated from tap water samples collected from different locations of the city were characterized for their antibiotic resistance, pathogenic properties and genetic diversity.

Methodology/Principal Findings

A total of 233 E. coli isolates obtained from 175 tap water samples were analysed for susceptibility to 16 different antibiotics and for the presence of genes associated with virulence and antibiotic resistance. Nearly 36% (n = 84) of the isolates were multi-drug(≥3 classes of antibiotics) resistant (MDR) and 26% (n = 22) of these were positive for extended spectrum β-lactamase (ESBL). Of the 22 ESBL-producers, 20 were positive for bla _CTX-M-15, 7 for bla _OXA-1-group (all had bla _OXA-47) and 2 for bla _CMY-2. Quinolone resistance genes, qnrS and qnrB were detected in 6 and 2 isolates, respectively. Around 7% (n = 16) of the isolates carried virulence gene(s) characteristic of pathogenic E. coli; 11 of these contained lt and/or st and thus belonged to enterotoxigenic E. coli and 5 contained bfp and eae and thus belonged to enteropathogenic E. coli. All MDR isolates carried multiple plasmids (2 to 8) of varying sizes ranging from 1.2 to >120 MDa. Ampicillin and ceftriaxone resistance were co-transferred in conjugative plasmids of 70 to 100 MDa in size, while ampicillin, trimethoprim-sulfamethoxazole and tetracycline resistance were co-transferred in conjugative plasmids of 50 to 90 MDa. Pulsed-field gel electrophoresis analysis revealed diverse genetic fingerprints of pathogenic isolates.

Significance

Multi-drug resistant E. coli are wide spread in public water supply in Dhaka city, Bangladesh. Transmission of resistant bacteria and plasmids through supply water pose serious threats to public health in urban areas.     

Computerized image analysis of Ki-67 in ductal breast carcinoma in situ.

OBJECTIVE: To develop and determine the staining protocols and computerized image analysis methods that are the most effective combination for performing quantitative analysis of Ki-67. STUDY DESIGN: We compared conventional bright-field light microscopy and refractive optical enhancement methods in combination with various immunodetection and filter enhancement methods, including immunogold in combination with epipolarization refractive optics and enzymatic conversion of chromogenic substrates in combination with optical filter enhancement. Initial Ki-67 tests were performed on lymph node tissues and cultured human breast cells and then applied to 200 ductal carcinoma in situ (DCIS) samples. DCIS acini were digitally acquired, and a region of interest was manually outlined in each one with a digital stylus to include only the cellular component; then the Ki-67 staining index was quantified by segmentation analysis. RESULTS: Although combining epipolarization analysis with immunohistogold staining was the most sensitive detection method, nonspecific binding was too high. The streptavidin-horseradish-peroxidase enzymatic conversion of 3,3'-diaminobenzidine (DAB) in combination with optical enhancement filters was the most effective method tested. Ki-67 stain was associated with dense fibrillar structures of the nucleoli in the less intensely staining nuclei and was most intense in paired nuclei. CONCLUSION: The method of measuring Ki-67 expression by DAB staining combined with optical enhancement filters and quantification via computer-assisted image analysis techniques produced objective and reproducible results. As such, this method can offer (1) less intraobserver and interobserver variability, (2) a digital archival record, and (3) a baseline for digital exchange of information between studies.     

Exogenous proline mitigates the detrimental effects of salt stress more than exogenous betaine by increasing antioxidant enzyme activities

Proline and betaine accumulate in plant cells under environmental stresses including salt stress. Here, we investigated effects of proline and betaine on the growth and activities of antioxidant enzymes in tobacco Bright Yellow-2 (BY-2) culture cells in suspension under salt stress. Both proline and betaine mitigated the inhibition of growth of BY-2 cells under salt stress and the mitigating effect of proline was more than that of betaine. Salt stress significantly decreased the activities of superoxide dismutase (SOD), catalase and peroxidase in BY-2 cells. Exogenous application of proline or betaine alleviated the reduction in catalase and peroxidase activities but not SOD activity under salt stress. In addition, proline was found to be effective in alleviating the inhibition of salt stress-induced catalase and peroxidase activities in BY-2 cells. Neither proline nor betaine directly scavenged superoxide (O(2)(-)) or hydrogen peroxide (H(2)O(2)). It is concluded that exogenous proline mitigates the detrimental effects of salt stress more than exogenous betaine because of its superior ability to increase the activities of antioxidant enzymes.     

Exogenous proline and glycinebetaine increase NaCl-induced ascorbate-glutathione cycle enzyme activities, and proline improves salt tolerance more than glycinebetaine in tobacco Bright Yellow-2 suspension-cultured cells

Up-regulation of the antioxidant system provides protection against NaCl-induced oxidative damage in plants. Antioxidants and activity of enzymes involved in the ascorbate-glutathione (ASC-GSH) cycle in tobacco Bright Yellow-2 (BY-2) were investigated to assess the antioxidant protection offered by exogenous proline and glycinebetaine (betaine from now on) against salt stress using cells grown in suspension culture. Reduced ascorbate (ASC) was detected in BY-2 cells but dehydroascorbate (DHA) was not. Large quantities of a reduced form of glutathione (GSH) and smaller quantities of an oxidized form of glutathione (GSSG) were detected in BY-2 cells. Salt stress significantly reduced the contents of ASC and GSH as well as activities of ASC-GSH cycle enzymes such as ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), and glutathione reductase (GR). Exogenous proline or betaine increased the activities of all enzymes except MDHAR involved in NaCl-induced ASC-GSH cycle. Levels of ASC and GSH in BY-2 cells under salt stress were lower in the presence of proline or betaine than in the absence of proline or betaine whereas there was no difference in redox status. Proline proved more effective than betaine in maintaining the activity of enzymes involved in NaCl-induced ASC-GSH cycle. Neither proline nor betaine had any direct protective effect on NaCl-induced enzyme activity involved in the antioxidant system; however, both improved salt tolerance by increasing enzyme activity. The present study, together with our earlier findings [Hoque MA, Okuma E, Banu MNA, Nakamura Y, Shimoishi Y, Murata Y. Exogenous proline mitigates the detrimental effects of salt stress more than exogenous betaine by increasing antioxidant enzyme activities. J Plant Physiol 2006;164:553-61.], suggests that proline offered greater protection against salt stress than betaine did because proline was more effective in increasing the activity of enzymes involved in the antioxidant system.     

Tissue-specific regulation of sodium/proton exchanger isoform 3 activity in Na(+)/H(+) exchanger regulatory factor 1 (NHERF1) null mice. cAMP inhibition is differentially dependent on NHERF1 and exchange protein directly activated by cAMP in ileum versus proximal tubule

The multi-PDZ domain containing protein Na(+)/H(+) Exchanger Regulatory Factor 1 (NHERF1) binds to Na(+)/H(+) exchanger 3 (NHE3) and is associated with the brush border (BB) membrane of murine kidney and small intestine. Although studies in BB isolated from kidney cortex of wild type and NHERF1(-/-) mice have shown that NHERF1 is necessary for cAMP inhibition of NHE3 activity, a role of NHERF1 in NHE3 regulation in small intestine and in intact kidney has not been established. Here a method using multi-photon microscopy with the pH-sensitive dye SNARF-4F (carboxyseminaphthorhodafluors-4F) to measure BB NHE3 activity in intact murine tissue and use it to examine the role of NHERF1 in regulation of NHE3 activity. NHE3 activity in wild type and NHERF1(-/-) ileum and wild type kidney cortex were inhibited by cAMP, whereas the cAMP effect was abolished in kidney cortex of NHERF1(-/-) mice. cAMP inhibition of NHE3 activity in these two tissues is mediated by different mechanisms. In ileum, a protein kinase A (PKA)-dependent mechanism accounts for all cAMP inhibition of NHE3 activity since the PKA antagonist H-89 abolished the inhibitory effect of cAMP. In kidney, both PKA-dependent and non-PKA-dependent mechanisms were involved, with the latter reproduced by the effect on an EPAC (exchange protein directly activated by cAMP) agonist (8-(4-chlorophenylthio)-2'O-Me-cAMP). In contrast, the EPAC agonist had no effect in proximal tubules in NHERF1(-/-) mice. These data suggest that in proximal tubule, NHERF1 is required for all cAMP inhibition of NHE3, which occurs through both EPAC-dependent and PKA-dependent mechanisms; in contrast, cAMP inhibits ileal NHE3 only by a PKA-dependent pathway, which is independent of NHERF1 and EPAC.     

Blocking neddylation elicits antiviral effect against hepatitis B virus replication

Molecular Biology Reports - Hepatitis B Virus (HBV) is the most common cause of chronic liver disease worldwide. The mechanisms that regulate HBV viral replication remain poorly defined. Here, we...     

Development and calibration of bio-kinetic model for surfactant biodegradation with combined respirometric and titrimetric measurements

Substrate removal mechanism in aerobic activated sludge processes was lately modeled using the simultaneous storage and growth (SSAG) phenomenon. The SSAG model was further refined with titrimetric components and successfully calibrated using both respirometric and titrimetric measurements for common substrate acetate. However, the improved SSAG model calibration was not verified with other organic substrates. Furthermore, very few studies are available in the literature on surfactant bio-kinetics, which generally use off-line experimental measurements with limited model-based interpretation. Therefore, the aim of this paper is to demonstrate its applicability for surfactant biodegradation using on-line measurements. Batch experiments were conducted using sodium dodecyl sulfate (SDS) as a test surfactant. Model calibration was done successfully for three different SDS concentrations using respirometric, titrimetric and combined respirometric-titrimetric measurement approaches. The parameter estimation results from all three stated combinations were statistically evaluated and found to be very close validating the model.     

Genome-wide analysis of genetic alterations in testicular primary seminoma using high resolution single nucleotide polymorphism arrays

Testicular germ cell tumors (TGCT) represent the most common malignancy among young males. To our knowledge no comprehensive Copy Number Variation (CNVs) studies of TGCT using high-resolution Single Nucleotide Polymorphism (SNP) array have been performed. By a genome-wide analysis of CNV and loss of heterozygosity (LOH) in 25 primary seminomas, we confirmed several previously reported genomic alterations and discovered eight novel genomic alterations including amplifications and homozygous deletions. Moreover, a comparison of genomic alterations of early and late stage seminoma identified CNVs that correlate with progression, which included deletions in chromosomes 4q, 5p, 9q, 13q and 20p and amplifications in chromosomes 9q and 13q. We compared previously perform Affymetrix expression analysis in a subset of samples and found robust correlation between expression and genomic alterations. Furthermore, high correlations (40-75%) were observed between CNV by SNP analysis and quantitative PCR. Our findings may lead to better understanding of TGTC's pathogenesis.