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91.
Comparison of broth microdilution,E Test,and agar dilution methods for antibiotic susceptibility testing of Campylobacter jejuni and Campylobacter coli 下载免费PDF全文
A standardized broth microdilution method was compared to the E test and an agar dilution method for the antimicrobial susceptibility testing of Campylobacter jejuni and C. coli isolates. A group of 47 human clinical isolates, 37 isolates from retail poultry, and 29 isolates from living turkeys (total, 113 isolates) was included in the study. These encompassed 92 C. jejuni and 21 C. coli strains. The MICs of six antimicrobial agents were determined by the broth microdilution and E test methods, and the strains of human origin were additionally tested by the agar dilution method. In general, broth microdilution MICs agreed within 1 log(2) MIC increment with 90.0% of E test results and 78.7% of agar dilution test results. The agar dilution method gave much lower gentamicin MICs than the broth microdilution method, but the data were significantly (P < 0.01) correlated and there was 100% agreement in the sensitivities and specificities in the comparison of the tests. The broth microdilution method had the highest sensitivity for analysis of the susceptibilities of Campylobacter to nalidixic acid and trimethoprim-sulfamethoxazole. The MICs of ciprofloxacin and erythromycin complied numerically by all three methods. The classification of the results and the correlation of the data demonstrated a high degree of agreement. All methods were equally suitable for the testing of the sensitivity of Campylobacter to tetracycline. Thus, the broth microdilution method appears to be an easy and reliable method for determination of the MICs of antibiotics for C. jejuni and C. coli, and it may offer an interesting alternative to MIC determination by the agar dilution technique or the E test. 相似文献
92.
Comparison of LightCycler-based PCR,COBAS amplicor CMV monitor,and pp65 antigenemia assays for quantitative measurement of cytomegalovirus viral load in peripheral blood specimens from patients after solid organ transplantation 总被引:2,自引:0,他引:2 下载免费PDF全文
Pang XL Chui L Fenton J LeBlanc B Preiksaitis JK 《Journal of clinical microbiology》2003,41(7):3167-3174
In order to evaluate the LightCycler-based PCR (LC-PCR) as a diagnostic assay technique, a classical pp65 antigenemia assay and the commercially available COBAS Amplicor CMV Monitor (CACM) assay were compared to the LC-PCR assay for the detection and quantitation of cytomegalovirus (CMV) load in 404 parallel specimens of peripheral blood from 66 patients after solid organ transplantation. A good correlation existed among these three assays (r congruent with 0.6, P < 0.0001). The LC-PCR assay was the most sensitive (54% of specimens positive) compared to the CACM (48.6%) and the pp65 antigenemia (26%) assays. The LC-PCR assay detected all samples found positive by using both the CMV pp65 antigenemia assay and the CACM assay. The LC-PCR also had the widest dynamic range (from 250 to 10(7) DNA copies/ml of plasma). No cross-reactions were found among CMV and Epstein-Barr virus, varicella-zoster virus, or herpes simplex virus in the LC-PCR by using amplification with specifically designed primer pairs. Precision, expressed as the coefficient of variation, was <3% with standard DNA from cell cultures and between 6.55 and 14.1% with clinical specimens in repeat LC-PCR runs. One run of the LC-PCR took half of the time required for the semiautomated CACM procedure. Because of its sensitivity, specificity, cost-effectiveness, and simplicity, the LC-PCR assay could replace the pp65 antigenemia and the CACM assays as the preferred technique for the surveillance, diagnosis, and monitoring of response of CMV diseases in high-risk populations. 相似文献
93.
Doris Mayr Sibylle Heim Kerstin Weyrauch Evelyn Zeindl‐Eberhart Anne Kunz Jutta Engel Thomas Kirchner 《Histopathology》2009,55(6):716-723
Aims: Her‐2/neu testing is used as a marker for Herceptin® therapy. The aim was to investigate new dual‐colour chromogenic in situ hybridization (CISH), in a large number of breast carcinomas (n = 205) with DNA‐specific dual‐colour probes (ZytoVision, Bremerhaven, Germany) and to compare the results with immunohistochemistry (n = 205) and fluorescence in situ hybridization (FISH) (n = 129). Methods and results: Paraffin‐embedded tissue of 205 patients was used. After immunohistochemistry with a focus on immunohistochemically uncertain cases, Her‐2/neu amplification using dual‐colour CISH (ZytoVision®) was analysed. Validation by FISH was performed. The results were: immunohistochemistry, 27.8% with strong expression, 53.7% with uncertain overexpression and 18.5% with no expression; FISH, 25.6% amplified and 74.4% negative; CISH, 35.6% amplified, 62.9% negative and 1.5% not evaluable. Comparison of immunohistochemistry with CISH: CISH negative in 100% with immunohistochemistry 0/1+, amplified in 82.5% with immunohistochemistry 3+; 5.9% contradictory results: 4.4% immunohistochemistry 3+ and negative by CISH, 1.5% negative in immunohistochemistry but amplified by CISH; FISH (129 cases), 8.5% contradictory results to immunohistochemistry, 6.2% immunohistochemistry 3+ and negative by FISH, 2.3% negative by immunohistochemistry and amplified by FISH; comparison of CISH and FISH, 94.6% same results, 3.9% different ones, 1.6% CISH not analysable. Conclusions: CISH, using dual‐colour probes (ZytoVision®) is as good as FISH for Her‐2/neu analysis. The few discrepant results are likely to be caused by polysomy or tumour heterogeneity. 相似文献
94.
The Gene Polymorphism of the Angiotensin I-Converting Enzyme Correlates with Tumor Size and Patient Survival in Colorectal Cancer Patients 下载免费PDF全文
95.
The Joint Standards Task Force of A.S.P.E.N. American Dietetic Association Dietitians in Nutrition Support Dietetic Practice Group Mary Russell MS RD Co-chair Marsha Stieber MSA RD Co-chair Susan Brantley MS RD Amy M. Freeman RD Jennifer Lefton MS RD Ainsley M. Malone MS RD Susan Roberts MS RD Janet Skates MS RD FADA Lorraine S. Young MS RD A.S.P.E.N. Board of Directors ADA Quality Management Committee 《Journal of the American Dietetic Association》2007,107(10):1815
The Standards of Practice for Registered Dietitians in Nutrition Support and the Standards of Professional Performance for the Registered Dietitian in Nutrition Support are key resources for RDs at all knowledge and performance levels. These standards can and should be used by RDs in daily practice to consistently improve and appropriately demonstrate competency and value as providers of safe and effective nutrition support therapy. The standards development and evaluation process is dynamic—these standards will be reviewed at least every 5 years for applicability to practice. Current and future initiatives of A.S.P.E.N. and ADA will provide information that will be used in these updates and in further clarifying and documenting the specific roles and responsibilities of practitioners at each level. As a quality initiative of A.S.P.E.N., its Dietetics Practice Section, ADA, and their DNS DPG, the standards themselves are an application of continuous quality improvement concepts and represent another very important collaborative endeavor. 相似文献
96.
OPG is regulated by beta-catenin and mediates resistance to TRAIL-induced apoptosis in colon cancer 总被引:1,自引:0,他引:1
Enrico N De Toni Susanne E Thieme Andreas Herbst Andrea Behrens Petra Stieber Andreas Jung Helmut Blum Burkhard G?ke Frank T Kolligs 《Clinical cancer research》2008,14(15):4713-4718
PURPOSE: Resistance to apoptosis is a hallmark of cancer and correlates with aggressiveness of tumors and poor prognosis. The Wnt/beta-catenin pathway plays a pivotal role in the genesis of colorectal cancer by mechanisms not fully elucidated yet. Previous studies have linked regulation of osteoprotegerin (OPG) in bone to Wnt/beta-catenin signaling. As OPG also serves as a decoy receptor for tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), we hypothesized that OPG might play a role in mediating resistance to apoptosis in colorectal cancer cells. EXPERIMENTAL DESIGN: Expression analysis and functional studies in human colorectal cancer cell lines and determination of expression in primary tumors and sera from patients with colorectal cancer. RESULTS: We found production of OPG in colorectal cancer cells to be regulated by beta-catenin/Tcf-4. Addition of exogenous OPG to colorectal cancer cells caused resistance to TRAIL. Similarly, accumulation of OPG in medium of cultivated cells caused resistance to TRAIL, and this could be reverted by removal of OPG. Furthermore, OPG levels were significantly increased in serum of patients with advanced disease. CONCLUSIONS: We conclude that the Wnt/beta-catenin pathway contributes to carcinogenesis and cancer cell survival by driving expression of OPG. Expression of the survival factor OPG might provide colorectal cancer cells with an essential growth advantage and contribute to cell invasion and metastasis. Inhibition of OPG expression might offer a new therapeutic approach for the treatment of patients with colorectal tumors overexpressing OPG and make these tumors sensitive to TRAIL-induced apoptosis. 相似文献
97.
Hans Krappweis Jutta Krappweis Wilhelm Kirch 《Zeitschrift fur Gesundheitswissenschaften》2000,8(1):4-13
The main purpose of Public health is improvement of the health state of the population. Thereby necessary coasts have to be considered. Public Health research is directly practice-related because of the development and implementation of health policy strategies. Important aims of the public health research are the realization of interventions in practice and their reevaluation. Health economy is an essential point of Public health. The public health research aims at analyzing the medical care and control systems. Further aims of the health economy are the individual processes of decisions of participating persons (e.g. physicians, patients)are object of research. Pharmacoeconomic aspects belong to an optimal therapy, that means the quality assurance and improvement with regard to circumstances. Quality assurance is not possible without the consideration of the state of knowledge. Only on the basis of actual data from the medical care system specific interventions on the political and individual level may be established. Subsequently these programs can be evaluated according to quality and cost outcomes. Drug information services and pharmacotherapy circles (Peer review groups)can contribute to an optimization in medical treatment. As a result these interventions are of consequence for health economy and medical care. 相似文献
98.
Dieter Riemann Jutta Kammerer Heidemarie Löw Martin H. Schmidt 《Journal of child psychology and psychiatry, and allied disciplines》1995,36(2):313-326
Abstract— The present study aimed at investigating the question whether abnormalities of sleep, especially disinhibition of rapid eye movement (REM) sleep, are already present in adolescents with primary major depressive disorder (MDD). Ten healthy controls assessed at home, 10 inpatients with MDD and 10 inpatients with schizophrenia (age range: 13–19 years) were investigated polysomnographically. REM latency was significantly shortened in MDD compared with the two other groups. Adolescents with MDD did not display disturbances of sleep continuity as typically observed in adults with major depression. The most pronounced impairment of sleep continuity was noted in schizophrenic patients. The results stress that shortened REM latency may already occur in adolescent depression. 相似文献
99.
Heike Peterziel Zoran Culig Jutta Stober Alfred Hobisch Christian Radmayr Georg Bartsch Helmut Klocker Andrew C. B. Cato 《International journal of cancer. Journal international du cancer》1995,63(4):544-550
Mutant androgen receptors are thought to contribute to hormone resistance in prostate carcinoma. The part they play in this process, however, is ill-defined. Here we report on transactivation by 2 mutant androgen receptors from prostatic tumors with single amino-acid exchanges in their hormone-binding domains. These exchanges enhance the transactivation property of the receptors, particularly to androsterone and androstanediol, 2 metabolized derivatives of testosterone present in the prostate. Additionally, they enhance the transactivation potential of the mutant receptors to hydroxyflutamide, an anti-androgen frequently used in hormone ablation therapy. The increased transactivation by the mutant receptors did not result from altered affinity of the receptors to the inducing ligands nor from measurable changes in conformation of the liganded receptors. Thus the single amino-acid exchanges identify differences in amino-acid-sequence requirements for transactivation and ligand binding in the hormone-binding domain of the androgen receptor. These results provide new insights into ligand-dependent transactivation, and form a framework for the search for effective antagonists to be used in prostate-cancer therapy. 相似文献
100.
Effects of antihistamines on leukotriene and cytokine release from dispersed nasal polyp cells 总被引:4,自引:0,他引:4
Küsters S Schuligoi R Hüttenbrink KB Rudert J Wachs A Szelenyi I Peskar BA 《Arzneimittel-Forschung》2002,52(2):97-102
In this study the effects of antihistamines on the release of eicosanoids and the pro-inflammatory cytokine tumor necrosis factor alpha (TNF alpha) were compared. Enzymatically dispersed cells from human nasal polyps served as an in vitro model of chronic respiratory mucosal inflammation. Nasal polyp cells (2 x 10(5)/ml) were sensitized with human IgE pre-incubated azelastine (CAS 58581-89-8), terfenadine (CAS 50679-08-8), levocabastine (CAS 79516-68-0) or cetirizine (CAS 83881-51-0), and stimulated with anti-human immunoglobulin E (IgE). Thromboxane B2 (TBX2) and leukotriene C4 (LTC4) were measured by radioimmunoassay (RIA), TNF alpha by enzyme-linked immunosorbent assay (ELISA). Data represent mean values of % inhibition estimated from the untreated positive control or mean IC50 (n = 5). Azelastine and terfenadine inhibited TNF alpha release with IC50 values of 6.2 mumol/l and 4.3 mumol/l, respectively. Terfenadine reduced TXB2 release by 37 +/- 15%, and LTC4 release was decreased by azelastine and terfenadine very potently by 86% and 100%, respectively. Azelastine shows anti-inflammatory properties in therapeutically relevant concentrations as assessed by its ability to reduce TNF alpha release as well as its ability to inhibit LTC4 production in allergically stimulated human nasal polyp cells. 相似文献