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1.
Single-step synthesis of novel 4-hydrazinothiazole derivatives 6a–e was achieved under mild conditions using the sequential four-components method involving isothiocyanate, aminoguanidine, carbonyl adduct, and α-haloketone derivatives. Deprotection of these hydrazinothiazoles was influenced by acylation, providing a novel group of diacylated molecular structures with a broader scope for the design of thiazolyl-containing drugs 7a and 7b . FTIR, 1H/13C NMR, LC–MS spectroscopy, and CHN elemental analyses were used to study the compound chemical structures. Using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay on human periodontal ligament fibroblast (HPDLF) cells, the 4-hydrazinothiazole derivatives were screened for cytotoxicity in an in vitro cytotoxicity investigation. The 4-hydrazinothiazole compound 6b bearing an isopropylidene-hydrazino group demonstrated strongly potent cytotoxicity against CAKI1 (IC50 = 1.65 ± 0.24 μM) and A498 (IC50 of 0.85 ± 0.24 μM). Furthermore, the chloroacetyl-containing thiazole compound 7a displayed efficient inhibition of growth against the test cell lines CAKI1 and A498 at low micromolar concentrations, IC50 0.78 and 0.74 μM, respectively.  相似文献   
2.
Moxifloxacin and ofloxacin are two broad-spectrum quinolone antibiotics. They are among the most widely used antibiotics, at this time, applied to control the COVID-19 pandemic. Hydroxychloroquine is an FDA-approved drug for the treatment of COVID-19. This work describes a simple, green, selective, and sensitive spectrofluorimetric method for the assay of moxifloxacin and ofloxacin in the presence of hydroxychloroquine, two co-administered mixtures used in the treatment of hospital-acquired pneumonia in patients with COVID-19. Simultaneous assay of hydroxychloroquine and moxifloxacin was carried out in methanol using a direct spectrofluorimetric method (method I) at 375 and 550 nm, respectively, after excitation at 300 nm. The direct spectrofluorimetric assay was rectilinear over concentration ranges 50.0–400.0 and 300.0–2500.0 ng/ml for hydroxychloroquine and moxifloxacin, respectively, with limits of detection (LOD) of 6.4 and 33.64 ng/ml and limits of quantitation (LOQ) of 19.4 and 102.6 ng/ml, respectively, for the two drugs. The assay for hydroxychloroquine and ofloxacin was carried out by measuring the first derivative synchronous amplitude for hydroxychloroquine at the zero crossing point of ofloxacin and vice versa at Δλ = 140 nm (method II). Hydroxychloroquine was measured at 266 nm, while ofloxacin was measured at 340 nm over the concentration range 4–40 ng/ml for hydroxychloroquine and 200–2000 ng/ml for ofloxacin with LOD of 0.467 and 25.3 ng/ml and LOQ of 1.42 and 76.6 ng/ml, respectively, for the two drugs. The two methods were validated following International Conference on Harmonization guidelines and were applied to the analysis of the two drugs in plasma with good percentage recoveries (109.73–93.17%).  相似文献   
3.
Journal of Plant Research - The current study examined the phylogenetic pattern of medicinal species of the family Apiaceae based on flavonoid groups production, as well as the overall mechanism of...  相似文献   
4.
Behçet''s disease (BD) is a chronic inflammatory disease. Immunological defects have been shown to play a significant role in the progression of BD. The serum levels of two long non-coding RNAs (lncRNAs), NEAT1 and MALAT1, were examined in patients with BD to identify their role in the disease pathogenesis. Both lncRNAs were mentioned as essential regulators of innate immune responses and have a crucial role in inflammatory diseases. Fifty patients with BD and a similar number of control individuals were involved in our study. At enrollment, data was collected from patients and controls, and the disease severity in active cases was determined using the Behçet''s Disease Current Activity Form (BDCAF). Levels of the two studied biomarkers in the serum, NEAT1 and MALAT1, were investigated by quantitative RT-PCR (qRT-PCR). NEAT1 levels were significantly turned down in BD patients (fold changes = 0.77, p = 0.0001) and correlated negatively with the BDCAF (r = −0.41; p = 0.003). On the other hand, the MALAT1 levels were significantly up-regulated in BD patients (fold changes = 2.65, p = 0.003). Serum levels of NEAT1 were significantly decreased in patients with active states than in stationary cases (0.387 versus 1.99, respectively; p = 0.01) and compared with controls (p = 0.001). Also, NEAT1 levels were significantly increased in patients with stationary states compared to controls (p = 0.03). There was a positive association between NEAT1 and MALAT1 levels among BD patients (r = 0.29, p = 0.04). Our findings demonstrate a possible role of NEAT1 and MALAT1 in the pathogenesis of BD.  相似文献   
5.
The tissue inhibitors of metalloproteinases (TIMPs) are endogenous inhibitors of the matrix metalloproteinases (MMPs). Since unregulated MMP activities are linked to arthritis, cancer, and atherosclerosis, TIMP variants that are selective inhibitors of disease-related MMPs have potential therapeutic value. The structures of TIMP/MMP complexes reveal that most interactions with the MMP involve the N-terminal pentapeptide of TIMP and the C-D beta-strand connector which occupy the primed and unprimed regions of the active site. The loop between beta-strands A and B forms a secondary interaction site for some MMPs, ranging from multiple contacts in the TIMP-2/membrane type-1 (MT1)-MMP complex to none in the TIMP-1/MMP-1 complex. TIMP-1 and its inhibitory domain, N-TIMP-1, are weak inhibitors of MT1-MMP; inhibition is not improved by grafting the longer AB loop from TIMP-2 into N-TIMP-1, but this change impairs binding to MMP-3 and MMP-7. Mutational studies with N-TIMP-1 suggest that its weak inhibition of MT1-MMP, as compared to other N-TIMPs, arises from multiple (>3) sequence differences in the interaction site. Substitutions for Thr2 of N-TIMP-1 strongly influence MMP selectivity; Arg and Gly, that generally reduce MMP affinity, have less effect on binding to MMP-9. When the Arg mutation is added to the N-TIMP-1(AB2) mutant, it produces a gelatinase-specific inhibitor with Ki values of 2.8 and 0.4 nM for MMP-2 and -9, respectively. Interestingly, the Gly mutant has a Ki of 2.1 nM for MMP-9 and >40 muM for MMP-2, indicating that engineered TIMPs can discriminate between MMPs in the same subfamily.  相似文献   
6.
Uropathogens develop biofilms on urinary catheters, resulting in persistent and chronic infections that are associated with resistance to antimicrobial therapy. Therefore, the current study was performed to control biofilm-associated urinary tract infections through assaying the anti-biofilm ability of lactic acid bacteria (LAB) against multidrug-resistant (MDR) uropathogens. Twenty LAB were obtained from pickles and fermented dairy products, and screened for their anti-biofilm and antimicrobial effects against MDR Escherichia coli U12 (ECU12). Lactobacillus plantarum Y3 (LPY3) (MT498405), showed the highest inhibitory effect and biofilm production. Pre-coating of a microtitre plate with LPY3 culture was more potent than co-incubation. Pre-coating with LPY3 culture generated a higher anti-biofilm effect with an adherence of 14.5% than cell free supernatant (CFS) (31.2%). Anti-biofilm effect of CFS was heat stable up to 100 °C with higher effect at pH 4–6. Pre-coating urinary catheter with LPY3 culture reduced the CFU/cm2 of ECU12 attached to the catheter for up to seven days. Meanwhile, CFS reduced the ECU12 CFU/cm2 for up to four days. Scanning electron microscope confirmed the reduction of ECU12 adherence to catheters after treatment with CFS. Therefore, Lactobacillus plantarum can be applied in medical devices as prophylactic agent and as a natural biointervention to treat urinary tract infections.  相似文献   
7.
Experimental and Applied Acarology - This study examined the acaricidal, histopathological and genotoxic effects of the entomopathogenic fungus Beauveria bassiana on engorged females of the fowl...  相似文献   
8.
Despite increased social awareness, marketing restraints, tobacco taxation, and available smoking cessation rehab programs, active and passive smoking remain a worldwide challenging epidemic and a key risk factor for cardiovascular diseases development. Although cardiovascular (CV) protection is more pronounced in women than in men due to estrogenic effects, tobacco cigarette smoking exposure seems to alter this protection by modulating estrogen actions via undefined mechanisms. Premenopausal cigarette smoking women are at higher risk of adverse CV effects than non-smokers. In this study, we investigated the impact of cigarette smoking on early CV injury after myocardial infarction (MI) in non-menopausal female mice. Aortic arch calcification, fibrosis, reactive oxygen species, and gene expression of inflammatory and calcification genes were exaggerated in mice exposed to cigarette smoke (CS). These findings suggest that aortic injury following MI, characterized by vascular smooth muscle cells transdifferentiation, calcification, inflammation, and collagen deposition but not cardiac dysfunction is exacerbated with CS exposure. The novel findings of this study highlight the importance of aortic injury on short and long-term prognosis in CS-exposed MI females. Linking those findings to estrogen alteration is probable and entails investigation.  相似文献   
9.
10.
Bone marrow-derived stromal cells (BMSC) are avidly recruited by experimental vascularizing tumors, which implies that they must respond to tumor-derived growth factor cues. In fact, BMSC chemotaxis and cell survival are regulated, in part, by the membrane type-1 matrix metalloproteinase (MT1-MMP), an MMP also involved in pro-MMP-2 activation and in degradation of the extracellular matrix (ECM). Given that impaired chemotaxis was recently observed in bone marrow cells isolated from a glucose 6-phosphate transporter-deficient (G6PT-/-) mouse model, we sought to investigate the potential MT1-MMP/G6PT signaling axis in BMSC. We show that MT1-MMP-mediated activation of pro-MMP-2 by concanavalin A (ConA) correlated with an increase in the sub-G1 cell cycle phase as well as with cell necrosis, indicative of a decrease in BMSC survival. BMSC isolated from Egr-1-/- mouse or MT1-MMP gene silencing in BMSC with small interfering RNA (siMT1-MMP) antagonized both the ConA-mediated activation of pro-MMP-2 and the induction of cell necrosis. Overexpression of recombinant full-length MT1-MMP triggered necrosis and this was signaled through the cytoplasmic domain of MT1-MMP. ConA inhibited both the gene and protein expression of G6PT, while overexpression of recombinant G6PT inhibited MT1-MMP-mediated pro-MMP-2 activation but could not rescue BMSC from ConA-induced cell necrosis. Cell chemotaxis in response to the tumorigenic growth factor sphingosine 1-phosphate was significantly abrogated in siMT1-MMP BMSC and in chlorogenic acid-treated BMSC. Altogether, we provide evidence for an MT1-MMP/G6PT signaling axis that regulates BMSC survival, ECM degradation, and mobilization. This may lead to optimized clinical applications that use BMSC as a platform for the systemic delivery of therapeutic or anti-cancer recombinant proteins in vivo.  相似文献   
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