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1.
A thiol compound, glutathione, is essential for healthy cell defence against xenobiotics and oxidative stress. Glutathione reductase (GR) and glutathione S-transferase (GST) are two glutathione-related enzymes that function in the antioxidant and the detoxification systems. In this study, potential inhibitory effects of methyl 4-aminobenzoate derivatives on GR and GST were examined in vitro. GR and GST were isolated from human erythrocytes with 7.63 EU/mg protein and 5.66 EU/mg protein specific activity, respectively. It was found that compound 1 (methyl 4-amino-3-bromo-5-fluorobenzoate with Ki value of 0.325±0.012 μM) and compound 5 (methyl 4-amino-2-nitrobenzoate with Ki value of 92.41±22.26 μM) inhibited GR and GST stronger than other derivatives. Furthermore, a computer-aided method was used to predict the binding affinities of derivatives, ADME characteristics, and toxicities. Derivatives 4 (methyl 4-amino-2-bromobenzoate) and 6 (methyl 4-amino-2-chlorobenzoate) were estimated to have the lowest binding energies into GR and GST receptors, respectively according to results of in silico studies.  相似文献   
2.
The fifth phage resistance factor from the prototype phage-insensitive strain Lactococcus lactis subsp. lactis ME2 has been characterized and sequenced. The genetic determinant for Prf (phage resistance five) was subcloned from the conjugative plasmid pTN20, which also encodes a restriction and modification system. Typical of other abortive resistance mechanisms, Prf reduces the efficiency of plaquing to 10(-2) to 10(-3) and decreases the plaque size and burst size of the small isometric-headed phage p2 in L. lactis subsp. lactis LM0230. However, normal-size plaques occurred at a frequency of 10(-4) and contained mutant phages that were resistant to Prf, even after repeated propagation through a sensitive host. Prf does not prevent phage adsorption or promote restriction and modification activities, but 90% of Prf+ cells infected with phage p2 die. Thus, phage infections in Prf+ cells are aborted. Prf is effective in both L. lactis subsp. lactis and L. lactis subsp. cremoris strains against several small isometric-headed phages but not against prolate-headed phages. The Prf determinant was localized by Tn5 mutagenesis and subcloning. DNA sequencing identified a 1,056-nucleotide structural gene designated abiC. Prf+ expression was obtained when abiC was subcloned into the lactococcal expression vector pMG36e. abiC is distinct from two other lactococcal abortive phage resistance genes, abiA (Hsp+, from L. lactis subsp. lactis ME2) and abi416 (Abi+, from L. lactis subsp. lactis IL416). Unlike abiA, the action of abiC does not appear to affect DNA replication. Thus, abiC represents a second abortive system found in ME2 that acts at a different point of the phage lytic cycle.  相似文献   
3.

The arthroconidial yeasts Magnusiomyces capitatus and M. clavatus are emerging opportunistic pulmonary pathogens. They are closely related and difficult to distinguish based on morphological and physiological traits. We applied an SYBR® green-based quantitative PCR (qPCR) assay to identify the species. We analyzed 30 reference strains originating from clinical and environmental sources by targeting the Rpb2 gene encoding the second largest subunit of RNA polymerase II. The qPCR assays were tested by direct identification of M. capitatus and M. clavatus in spiked sputum and household dishwasher swabs, respectively, as models for clinical and environmental samples. The assays were proved to be reliable for species-level identification of both species, with 100% sensitivity and 100% specificity, lowest inter-assay deviations (RSDr?≤?1.65%, R2 values >0.99), detection limit of 10 theoretical copy number of target DNA, and detection cell limit of ≥5000 yeast cells from spiked sputum samples. The developed qPCR assay is a practical molecular approach for the detection of M. capitatus and M. clavatus that can be used as a stand-alone assay or in conjunction with culture-dependent approaches.

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4.

Osteoarthritis (OA) is a common condition that impacts many people worldwide and involves weight-bearing joints, resulting in chronic pain. In this study, we aimed to compare the effectiveness of inpatient and outpatient physical therapy modalities and spa combination treatments on pain and functional status in patients with knee osteoarthritis. Seventy-four patients diagnosed with primary knee osteoarthritis were included in this study. The patients were randomized into two groups, inpatient (n?=?37) and outpatient (n?=?37) physical therapy. All patients received a physical therapy program (superficial heater + deep heater + transcutaneous electrical nerve stimulation) for 2 weeks and spa therapy. All cases were evaluated clinically, laboratory, and radiographically. In order to evaluate pain and functional status, the Visual Analogue Scale (VAS), Western Ontario and McMaster Universities osteoarthritis index (WOMAC), and Timed Up and Go (TUG) test were used before and after treatment. There was no significant difference between the two groups in the TUG test and WOMAC scores (p?>?0.05). However, a significant difference was found in VAS scores in favor of the outpatient group (p?<?0.05). As a result, although there was a significant improvement in pain scores in the outpatient group, multicenter studies with larger patient groups may provide more evidence.

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5.
BackgroundCoronary ischemia can lead to myocardial damage and necrosis. The pathogenesis of cardiovascular diseases often includes increased oxidative stress and decreased antioxidant defense. The study aimed to assess levels of ischemia modified albumin (IMA), malondialdehyde acid (MDA), superoxide dismutase (SOD), and catalase in individuals diagnosed with ST elevated myocardial infarction (STEMI) and non-STEMI.MethodsThe present study prospectively included 50 STEMI patients, 55 NSTEMI patients, and 55 healthy subjects. Only patients who were recently diagnosed with STEMI or NSTEMI were included in this study. IMA, MDA, SOD, and catalase activities were measured spectrophotometrically. Significant coronary artery lesions were determined by angiography.ResultsPatients with ACS had significantly greater IMA and MDA values than the healthy controls (p<0.001). Besides, patients with STEMI had IMA levels that were significantly greater than those of the patients with NSTEMI (p<0.001), while the reverse was true for MDA levels (p<0.001). The healthy controls had the highest levels of SOD and catalase levels, followed by patients with STEMI and patients with NSTEMI, respectively (p<0.001). There was a significant negative correlation among MDA and SOD with catalase levels (r = -0.771 p<0.001 MDA vs catalase; r = -0.821 p<0.001 SOD vs catalase).ConclusionsData obtained in this study reveals that compared to healthy controls, STEMI and NSTEMI patients had increased levels of MDA and IMA and decreased levels of SOD and catalase.  相似文献   
6.

Purpose

Although chronic hepatitis C virus (HCV) infection has been treated with the combination of interferon alpha (IFN-α) and ribavirin (RBV) for over a decade, the mechanism of antiviral synergy is not well understood. We aimed to determine the synergistic antiviral mechanisms of IFN-α and RBV combination treatment using HCV cell culture.

Methods

The antiviral efficacy of IFN-α, RBV alone and in combination was quantitatively measured using HCV infected and replicon cell culture. Direct antiviral activity of these two drugs at the level of HCV internal ribosome entry site (IRES) mediated translation in Huh-7 cell culture was investigated. The synergistic antiviral effect of IFN-α and RBV combination treatment was verified using both the CalcuSyn Software and MacSynergy Software.

Results

RBV combination with IFN-α efficiently inhibits HCV replication cell culture. Our results demonstrate that IFN-α, interferon lambda (IFN-λ) and RBV each inhibit the expression of HCV IRES-GFP and that they have a minimal effect on the expression of GFP in which the translation is not IRES dependent. The combination treatments of RBV along with IFN-α or IFN-λ were highly synergistic with combination indexes <1. We show that IFN-α treatment induce levels of PKR and eIF2α phosphorylation that prevented ribosome loading of the HCV IRES-GFP mRNA. Silencing of PKR expression in Huh-7 cells prevented the inhibitory effect of IFN-α on HCV IRES-GFP expression. RBV also blocked polyribosome loading of HCV-IRES mRNA through the inhibition of cellular IMPDH activity, and induced PKR and eIF2α phosphorylation. Knockdown of PKR or IMPDH prevented RBV induced HCV IRES-GFP translation.

Conclusions

We demonstrated both IFN-α and RBV inhibit HCV IRES through prevention of polyribosome formation. The combination of IFN-α and RBV treatment synergistically inhibits HCV IRES translation via using two different mechanisms involving PKR activation and depletion of intracellular guanosine pool through inhibition of IMPDH.  相似文献   
7.
An in vitro hair perforation test is used to differentiate isolates of Trichophyton mentagrophytes and Trichophyton rubrum complexes because morphological criteria are insufficient. Here, we performed in vitro hair perforation tests using blond prepubertal hair and albino adult hair to determine whether they differentiate between fungal species. We tested 43 well-characterized dermatophyte strains, Arthroderma spp. [n = 4], Epidermophyton floccosum [n = 1], Microsporum spp. [n = 8], and Trichophyton spp. [n = 30], and examined hair perforation at 3–30 days postinoculation (p.i.). The perforation times were not significantly different between the two hair types (P > 0.05). The T. mentagrophytes complex strains perforated hair 4–5 days p.i., whereas T. rubrum complex strains perforated hair 13–30 days p.i., except for Trichophyton violaceum, which perforated hair after 6–7 days. Thus, the hair perforation test is highly sensitive (100 %) and specific (100 %) for differentiating T. mentagrophytes from T. rubrum complexes 5 days p.i. At 14 and 30 days, the sensitivity and negative predictive value of the test remained unchanged (100 %), but the specificity was reduced (64.3 and 14.3 %, respectively). Consistent with previous reports, we observed “perforating organs” of zoophilic Microsporum canis and geophilic Microsporum gypseum at 4 and 3 days, respectively. This paper offers a “low-cost” and “low-tech” alternative to differentiating dermatophyte species where standard morphological techniques fail and/or where molecular techniques are not a viable option.  相似文献   
8.
Our aim in this study was to investigate the effect of moderate acute alcohol administration on cysteine protease mediated neuronal apoptosis and nitric oxide production in the traumatic brain injury. A total of 29 adult Sprague–Dawley male rats weighing 250–300 g were used. The rats were allocated into four groups. The first group was the control (sham-operated) group in which only a craniotomy was performed, the others were alcohol, trauma and trauma + alcohol groups. Caspase-3 enzyme activity in the trauma group increased significantly in comparison with the control group. The alcohol given group showed a decreased caspase-3 enzyme activity compared to the trauma group. The level of caspase-3 enzyme activity in the alcohol + trauma group decreased in comparison to the trauma group. SF/FEL ratio of cathepsin-L enzyme activity in the trauma group was significantly higher than in the control group. Our results indicate that moderate alcohol consumption may have protective effects on apoptotic cell death after traumatic brain injury. Protective effects of moderate ethanol consumption might be related to inhibition of lysosomal protease release and nitric oxide production.  相似文献   
9.
4-Amino-N-(4-sulfamoylphenyl)benzamide was synthesized by reduction of 4-nitro-N-(4-sulfamoylphenyl)benzamide and used to synthesize novel acridine sulfonamide compounds, by a coupling reaction with cyclic-1,3-diketones and aromatic aldehydes. The new compounds were investigated as inhibitors of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1), and more precisely the cytosolic isoforms hCA I, II and VII. hCA I was inhibited in the micromolar range by the new compounds (KIs of 0.16–9.64 μM) whereas hCA II and VII showed higher affinity for these compounds, with KIs in the range of 15–96 nM for hCA II, and of 4–498 nM for hCA VII. The structure–activity relationships for the inhibition of these isoforms with the acridine–sulfonamides reported here were also elucidated.  相似文献   
10.
Plant-based foods have become attractive for scientists and food producers. Beneficial effects related to their consumption as dietary supplements are due to the presence of natural occurring secondary metabolites. In this context, studies on these products are important for natural and safely food ingredients evaluation. The aim of this study was to evaluate root extract of eight Asphodeline species as antioxidants, enzyme inhibitors and phytochemical content. Spectrophotometric antioxidant and enzyme inhibitory assays were performed. Total phenolic and flavonoids contents as well as the chemical free-anthraquinones profiles were determined using routinely procedure (HPLC-PDA). Data show that Asphodeline roots can be considered as a new source of natural compounds and can be used as a valuable dietary supplement. Some differences related to biological activities can be inferred to other phytochemicals that can be considered in the future for their synergic or competitive activities.  相似文献   
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