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排序方式: 共有4230条查询结果,搜索用时 15 毫秒
101.
Kalaimaran Francina Cecilia Ramalingam Ravindhran Munusamy Rajiv Gandhi Appadurai Daniel Reegan Kedike Balakrishna Savarimuthu Ignacimuthu 《Parasitology research》2014,113(9):3477-3484
The mosquitocidal activity of different fractions and isolated compounds from the ethyl acetate extract of Ecbolium viride root was assessed on larvae and pupae of Culex quinquefasciatus Say (Diptera: Culicidae). The larvae and pupae were exposed to concentrations of 6.125, 12.5, 25 and 50 ppm for fractions and 1, 2.5, 5 and 10 ppm for compound. Among the 12 fractions screened, fraction 6 from the ethyl acetate extract of E. viride was recorded to have the highest larvicidal and pupicidal activities against C. quinquefasciatus. The lethal concentration (LC50 and LC90) values of fraction 6 were 4.26 and 9.0 ppm against C. quinquefasciatus larvae and 6.55 and 12.19 ppm against C. quinquefasciatus pupae, respectively, in 24 h. Fraction 7 was recorded to have moderate activity with LC50 and LC90 values of 11.25 and 25.02 ppm against C. quinquefasciatus larvae and 13.33 and 31.15 ppm against C. quinquefasciatus pupae, respectively, in 24 h. Ecbolin A and ecbolin B were identified from fractions 7 and 6, respectively. The structure of the isolated compounds was identified on the basis of spectral data (1H NMR and 13C NMR) and compared with literature spectral data. Further, the isolated compound, ecbolin B, from fraction 6 was recorded to have strong larvicidal and pupicidal activities than ecbolin A. The LC50 and LC90 values of ecbolin B on C. quinquefasciatus larvae were 1.36 and 2.76 ppm, and on pupae, these were 1.54 and 3.51 ppm, respectively. The present results suggest that ecbolin B could be used as a mosquitocidal agent against C. quinquefasciatus. 相似文献
102.
George P. Christophi Tiffany Caza Christopher Curtiss Divya Gumber Paul T. Massa Steve K. Landas 《Experimental and molecular pathology》2014
Sarcoidosis is an immune-mediated multisystem disease characterized by the formation of non-caseating granulomas. The pathogenesis of sarcoidosis is unclear, with proposed infectious or environmental antigens triggering an aberrant immune response in susceptible hosts. Multiple pro-inflammatory signaling pathways have been implicated in mediating macrophage activation and granuloma formation in sarcoidosis, including IFN-γ/STAT-1, IL-6/STAT-3, and NF-κB. It is difficult to distinguish sarcoidosis from other granulomatous diseases or assess disease severity and treatment response with histopathology alone. Therefore, development of improved diagnostic tools is imperative. Herein, we describe an efficient and reliable technique to classify granulomatous disease through selected gene expression and identify novel genes and cytokine pathways contributing to the pathogenesis of sarcoidosis. We quantified the expression of twenty selected mRNAs extracted from formalin-fixed paraffin embedded (FFPE) tissue (n = 38) of normal lung, suture granulomas, sarcoid granulomas, and fungal granulomas. Utilizing quantitative real-time RT-PCR we analyzed the expression of several genes, including IL-6, COX-2, MCP-1, IFN-γ, T-bet, IRF-1, Nox2, IL-33, and eotaxin-1 and revealed differential regulation between suture, sarcoidosis, and fungal granulomas. This is the first study demonstrating that quantification of target gene expression in FFPE tissue biopsies is a potentially effective diagnostic and research tool in sarcoidosis. 相似文献
103.
Ma X Helgason E Phung QT Quan CL Iyer RS Lee MW Bowman KK Starovasnik MA Dueber EC 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(24):9378-9383
Tank-binding kinase (TBK)1 plays a central role in innate immunity: it serves as an integrator of multiple signals induced by receptor-mediated pathogen detection and as a modulator of IFN levels. Efforts to better understand the biology of this key immunological factor have intensified recently as growing evidence implicates aberrant TBK1 activity in a variety of autoimmune diseases and cancers. Nevertheless, key molecular details of TBK1 regulation and substrate selection remain unanswered. Here, structures of phosphorylated and unphosphorylated human TBK1 kinase and ubiquitin-like domains, combined with biochemical studies, indicate a molecular mechanism of activation via transautophosphorylation. These TBK1 structures are consistent with the tripartite architecture observed recently for the related kinase IKKβ, but domain contributions toward target recognition appear to differ for the two enzymes. In particular, both TBK1 autoactivation and substrate specificity are likely driven by signal-dependent colocalization events. 相似文献
104.
Doi H Iyer TK Carpenter E Li H Chang KM Vonderheide RH Kaplan DE 《Hepatology (Baltimore, Md.)》2012,55(3):709-719
Chronic hepatitis C virus (HCV) infection is a leading cause of cirrhosis and hepatocellular carcinoma (HCC). Both advanced solid tumors and HCV have previously been associated with memory B-cell dysfunction. In this study, we sought to dissect the effect of viral infection, cirrhosis, and liver cancer on memory B-cell frequency and function in the spectrum of HCV disease. Peripheral blood from healthy donors, HCV-infected patients with F1-F2 liver fibrosis, HCV-infected patients with cirrhosis, patients with HCV-related HCC, and non-HCV-infected cirrhotics were assessed for B-cell phenotype by flow cytometry. Isolated B cells were stimulated with anti-cluster of differentiation (CD)40 antibodies and Toll-like receptor (TLR)9 agonist for assessment of costimulation marker expression, cytokine production, immunoglobulin (Ig) production, and CD4(+) T-cell allostimulatory capacity. CD27(+) memory B cells and, more specifically, CD27(+) IgM(+) B cells were markedly less frequent in cirrhotic patients independent of HCV infection. Circulating B cells in cirrhotics were hyporesponsive to CD40/TLR9 activation, as characterized by CD70 up-regulation, tumor necrosis factor beta secretion, IgG production, and T-cell allostimulation. Last, blockade of TLR4 and TLR9 signaling abrogated the activation of healthy donor B cells by cirrhotic plasma, suggesting a role for bacterial translocation in driving B-cell changes in cirrhosis. CONCLUSION: Profound abnormalities in B-cell phenotype and function occur in cirrhosis independent of HCV infection. These B-cell defects may explain, in part, the vaccine hyporesponsiveness and susceptibility to bacterial infection in this population. 相似文献
105.
106.
Ashish D Diwan Anthony Leong Richard Appleyard Divya Bhargav Zhi Ming Fang Aiqun Wei 《Indian Journal of Orthopaedics》2013,47(6):540-546
Background:
Osteoporosis is characterized by low bone mass, bone fragility and increased susceptibility to fracture. Fracture healing in osteoporosis is delayed and rates of implant failure are high with few biological treatment options available. This study aimed to determine whether a single dose of bone morphogenetic protein-7 (BMP-7) in a collagen/carboxy-methyl cellulose (CMC) composite enhanced fracture healing in an osteoporotic rat model.Materials and Methods:
An open femoral midshaft osteotomy was performed in female rats 3 months post-ovarectomy. Rats were randomized to receive either BMP-7 composite (n = 30) or composite alone (n = 30) at the fracture site during surgery. Thereafter calluses were collected on days 12, 20 and 31. Callus cross-sectional area, bone mineral density, biomechanical stiffness and maximum torque, radiographic bony union and histological callus maturity were evaluated at each time point.Results:
There were statistically significant increases in bone mineral density and callus cross-section area at all time points in the BMP-7 group as compared to controls and biomechanical readings showed stronger bones at day 31 in the BMP-7 group. Histological and radiographic evaluation indicated significant acceleration of bony union in the BMP-7 group as compared to controls.Conclusion:
This study demonstrated that BMP-7 accelerates fracture healing in an oestrogen-deficient environment in a rat femoral fracture healing model to scientific relevance level I. The use of BMP-7 composite could offer orthopedic surgeons an advantage over oestrogen therapy, enhancing osteoporotic fracture healing with a single, locally applied dose at the time of surgery, potentially overcoming delays in healing caused by the osteoporotic state. 相似文献107.
The STOP‐BANG questionnaire screens for obstructive sleep apnoea. We retrospectively analysed the independent association of pre‐operative variables with postoperative critical care admission using multivariable logistic regression for patients undergoing elective surgery from January to December 2011. Of 5432 patients, 338 (6.2%) were admitted postoperatively to the critical care unit. In multivariate analysis, the odds ratios (95% CI) for critical care admission were: 2.2 (1.1–4.6), p = 0.037; 3.2 (1.2–8.1), p = 0.017; and 5.1 (1.8–14.9), p = 0.002, for STOP‐BANG scores of 4, 5 and ≥ 6, respectively. The odds ratio was also independently increased for: each year of age, 1.015 (1.004–1.026), p = 0.019; asthma, 1.6 (1.1–2.4), p = 0.016; obstructive sleep apnoea, 3.2 (1.9–5.6), p < 0.001; and for ASA physical status 2, 3 and ≥ 4, 2.1 (1.4–3.3), 6.5 (3.9–11.0), 6.3 (2.9–13.8), respectively, p < 0.001 for all. 相似文献
108.
109.
Trask PC Mitra D Iyer S Candrilli SD Kaye JA 《International journal of hematology》2012,95(5):535-544
We conducted a review of patient medical records to assess treatment response patterns and prognostic indicators of response among chronic myeloid leukemia (CML) patients in the United States, the United Kingdom, Germany, and Japan. All 1,063 patients selected met the following inclusion criteria: aged 18 or older and in chronic phase at the time of diagnosis, Philadelphia chromosome and/or BCR-ABL positive, received first-line treatment with imatinib, and not enrolled in a randomized clinical trial during the period of retrospective review. Multivariable logistic regression models were used to evaluate prognostic indicators of complete hematological response (CHR), complete cytogenetic response (CCyR), and complete or major molecular response (C/MMR). Among patients treated with first-line imatinib, CHR at three months, CCyR at 12 months, and C/MMR at 18 months were observed in 53, 53.1, and 57.8 % of patients, respectively. Among patients treated with second-line dasatinib or nilotinib, CHR was achieved at three months in 49 and 42 %, CCyR at 12 months in 32 and 23 %, and MMR at 18 months in 30.5 and 26.1 % of patients, respectively. Prognostic indicators of first-line response included age, race, and Sokal score. For second-line treatment, duration of first-line hematological response and choice of drug used were also significant. 相似文献
110.
Mukundan H Price DN Goertz M Parthasarathi R Montaño GA Kumar S Scholfield MR Anderson AS Gnanakaran S Iyer S Schmidt J Swanson BI 《Tuberculosis (Edinburgh, Scotland)》2012,92(1):38-47
Lipoarabinomannan (LAM) is a critical virulence factor in the pathogenesis of Mycobacterium tuberculosis, the causative agent of tuberculosis. LAM is secreted in urine and serum from infected patients and is being studied as a potential diagnostic indicator for the disease. Herein, we present a novel ultra-sensitive and specific detection strategy for monomeric LAM based on its amphiphilic nature and consequent interaction with supported lipid bilayers. Our strategy involves the capture of LAM on waveguides functionalized with membrane mimetic architectures, followed by detection with a fluorescently labeled polyclonal antibody. This approach offers ultra-sensitive detection of lipoarabinomannan (10?fM, within 15?min) and may be extended to other amphiphilic markers. We also show that chemical deacylation of LAM completely abrogates its association with the supported lipid bilayers. The loss of signal using the waveguide assay for deacylated LAM, as well as atomic force microscopy (AFM) images that show no change in height upon addition of deacylated LAM support this hypothesis. Mass spectrometry of chemically deacylated LAM indicates the presence of LAM-specific carbohydrate chains, which maintain antigenicity in immunoassays. Further, we have developed the first three-dimensional structural model of mannose-capped LAM that provides insights into the orientation of LAM on supported lipid bilayers. 相似文献