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221.
Excessive neutrophil infiltration is a major component in septic lung injury, although the signaling mechanisms behind pulmonary recruitment of neutrophils in polymicrobial sepsis remain elusive. Herein, we hypothesized that Rho-kinase activity may play a significant role in pulmonary neutrophil recruitment and tissue damage in abdominal sepsis. Male C57BL/6 mice were treated with the Rho-kinase inhibitor Y-27632 (0.5 or 5 mg/kg) before cecal ligation and puncture (CLP). Bronchoalveolar lavage fluid and lung tissue were harvested for analysis of neutrophil infiltration, as well as edema and CXC chemokine formation. Blood was collected for analysis of Mac-1 on neutrophils and CD40L on platelets as well as soluble CD40L and matrix metalloproteinase 9 (MMP-9) in plasma. Cecal ligation and puncture triggered significant pulmonary damage characterized by neutrophil infiltration, increased levels of CXC chemokines, and edema formation in the lung. Furthermore, CLP upregulated Mac-1 expression on neutrophils, decreased CD40L on platelets, and increased soluble CD40L and MMP-9 in the circulation. Interestingly, inhibition of Rho-kinase dose-dependently decreased CLP-induced neutrophil expression of Mac-1, formation of CXC chemokines and edema, as well as neutrophil infiltration and tissue damage in the lung. Moreover, Rho-kinase inhibition significantly reduced sepsis-provoked gene expression of CXC chemokines in alveolar macrophages. In contrast, Rho-kinase inhibition had no effect on platelet shedding of CD40L or plasma levels of MMP-9 in septic mice. In conclusion, these data demonstrate that the Rho-kinase signaling pathway plays a key role in regulating pulmonary infiltration of neutrophils and tissue injury via regulation of CXC chemokine production in the lung and Mac-1 expression on neutrophils in abdominal sepsis.  相似文献   
222.
Biotin carboxylase (AccC) protein plays an essential role in cell wall biosynthesis in majority of bacterial genera. Inhibition of cell wall biosynthesis might be an ideal way to control the bacterial multiplication in the host system. AccC is one of the promising targets for the antibacterial drugs production. The benzimidazole derivatives are hopeful biotin carboxylase inhibitors, which sensitizes to the Escherichia coli (E. coli) and many other bacterial species too. In steam of developing better benzimidazole derivatives, we describe a quantitative pharmacophore model of benzimidazole derivatives using Phase module of Schr?dinger LLC. This model suggested that the following features are essential for ligand binding, i.e., two aromatic rings, two hydrogen bond donors, one hydrogen bond acceptor, and one hydrophobic group. Further, atom-based 3D-QSAR model was constructed using training set of 37 inhibitors. The constructed QSAR model has cross validated co-efficient value of (Q 2) 0.736 and regression co-efficient value of (R 2) 0.937. The external validation indicated that our QSAR model possessed high predicted powers with $ r_{o}^{2} $ value of 0.933, $ r_{\text m}^{2} $ value of 0.876. The best active and least active compounds were docked into the active site of receptor using Glide and hotspots of the active site were analyzed. The QSAR elucidated here for benzimidazole derivatives combined with their binding information will provide an opportunity to explore the chemical space to promote the potency of AccC inhibitors.  相似文献   
223.
Thymoquinone (TQ) is a bioactive component derived from the medicinal plant Nigella sativa. Recent studies reported that TQ exhibited cytotoxic effects in several cancer cell lines. Currently, no information in the literature is found concerning its mechanisms and cytotoxicity on neuroblastoma cells. In this study, the cytotoxicity of TQ in mouse neuroblastoma cells (Neuro-2a) was investigated. Our results showed that TQ significantly reduced viability of Neuro-2a cells than normal neuronal cells. Apoptosis induction by TQ was confirmed by DAPI and AO/PI staining. TQ triggered the apoptotic pathway, which was characterized by increased Bax/Bcl-2 ratio. TQ significantly increased the expression of pro-apoptotic protein Bax, whereas decreased the expression of anti-apoptotic protein Bcl-2, which leads to the release of cytochrome c from mitochondria into the cytoplasm. Moreover, TQ treatment directs the activation of caspase-3 followed by the cleavage of poly(ADP-ribose) polymerase (PARP). Interestingly, we also observed that TQ down-regulated caspase inhibitor X-linked inhibitor of apoptosis protein (XIAP). These results indicate that TQ induces apoptosis via caspase-3 activation with down-regulation of XIAP in Neuro-2a cells.  相似文献   
224.
Antithrombotic activity of a protease purified from a medicinal mushroom, Ganoderma lucidum, has been evaluated platelet aggregation in vitro and pulmonary thrombosis in vivo. The purified protease exhibited concentration dependent inhibitory effects on platelet aggregation induced by ADP (adenosine diphosphate), with an IC(50) value of 2.4 mg/mL. The purified protease protected mice against thrombotic death or paralysis induced by collagen and epinephrine in a dose dependent manner when administered orally. It produced a significant inhibition of thrombotic death or paralysis at 60 μg/kg body weight, while aspirin produced a significant inhibition of thrombosis at 10-20 mg/kg body weight. The purified protease also has showed fibrinolytic activity and alters coagulation parameters such as activated partial thromboplastin time (APTT), and thrombin time (TT) in rat platelet. These results suggested that the antithrombotic activity of Ganoderma lucidum protease might be due to antiplatelet activity rather than anticoagulation activity.  相似文献   
225.
During the synthesis of the bulk drug Raloxifene hydrochloride, eight impurities were observed, four of which were found to be new. All of the impurities were detected using the gradient high performance liquid chromatographic (HPLC) method, whose area percentages ranged from 0.05 to 0.1%. LCMS was performed to identify the mass number of these impurities, and a systematic study was carried out to characterize them. These impurities were synthesized and characterized by spectral data, subjected to co-injection in HPLC, and were found to be matching with the impurities present in the sample. Based on their spectral data (IR, NMR, and Mass), these impurities were characterized as Raloxifene-N-Oxide [Impurity: 1]; EP impurity A [Impurity: 2]; EP impurity B [Impurity: 3]; Raloxifene Dimer [Impurity: 4]; HABT (6-Acetoxy-2-[4-hydroxyphenyl]-1-benzothiophene or 6-Hydroxy-2-[4-acetoxyphenyl]-1-benzothiophene) [Impurity: 5]; PEBE (Methyl[4-[2-(piperidin-1-yl)ethoxy]]benzoate) [Impurity: 6]; HHBA (1-[6-hydroxy-2-(4-hydroxyphenyl)-1-benzothiophen-3-yl]ethanone) [Impurity: 7]; 7-MARLF (7-Acetyl-[6-hydroxy-2-(4-hydroxyphenyl)-1-benzothiophen-3-yl][4-[2-(piperidin-1-yl)ethoxy]phenyl methanone) [Impurity: 8]; of which impurities 5–8 are reported for the first time.  相似文献   
226.
Possible gallbladder rupture should be considered in any patient with blunt abdominal trauma and vague symptoms who has been inebriated. Peritoneal lavage and endoscopic or percutaneous cholangiography, if feasible, are the preferred diagnostic methods during the initial period after the gallbladder rupture. Later, when encapsulation occurs, ultrasonic examination of the mass together with guided aspiration of the bilious pseudocyst may provide the most useful diagnostic information.  相似文献   
227.
Purpose: To report a case of Kabuki make-up syndrome (KMS) or Niikawa-Kuroki syndrome with Coats-type retinal telangiectasia, which has not been previously reported. Methods: Observational case report. Conclusions: There have been only two reports of retinal pigmentation abnormalities and a single case of bilateral macular deposits in KMS, but this is the first report of a Coats type retinal telangiectasia. This case highlights the importance of thorough posterior segment examination in cases of KMS.  相似文献   
228.
Soil contamination, such as heavy metals and benzene compounds, is a widespread problem on military installations. It is important to be able to determine the effects of soil contamination before any adverse effects appear in organisms in surrounding areas. We examined gene expression in Arabidopsis thaliana grown in soil from three sites at the Radford Army Ammunition Plant in Radford, Virginia, USA, using DNA microarrays. We analyzed soil, germination, and growth rate to compare with the microarray data. Soil contamination affected both external phenotype and gene expression. Plants grown in soil with high levels of contaminants were chloritic and were smaller than control plants grown in potting soil. Plants grown in soil with the highest copper concentration had the lowest growth rates and had genes up-regulated across several functional groups. Plants grown in soils with elevated lead had many genes down-regulated that were related to photosystem II, metabolism, cellular transport, and protein synthesis. Genes consistently up-regulated across most microarrays were genes related to photosystem I, genes related to water deprivation and oxidative stress response, heat shock proteins, and toxin catabolism genes such as glutathiones. DNA microarrays, in concert with a model genetic organism such as A. thaliana, were an effective assessment tool to determine the presence of toxic substances in soil at a site used for the production of military explosives.  相似文献   
229.
Atypical presentations of cutaneous tuberculosis are not so uncommon and are frequently overlooked in clinical practice, leading to late diagnosis and increased morbidity. We report three cases of lupus vulgaris with atypical presentations. The cases mimicked other chronic skin lesions like actinomycosis, mycetoma, and so on. Strong clinical suspicion, histopathology, and response to antituberculous treatment led to the diagnosis and all three had excellent response to treatment. Today, when tuberculosis threatens to burst into pandemics again, early diagnosis and treatment are more important than ever for control and prevention of morbidity.  相似文献   
230.
Aspergillus peritonitis is a rare, potentially fatal complication of continuous ambulatory peritoneal dialysis (CAPD). We report a case of CAPD peritonitis caused by Aspergillus terreus in a 55-year-old female patient.  相似文献   
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