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31.
Mycobacterium haemophilum: microbiology and expanding clinical and geographic spectra of disease in humans. 总被引:3,自引:0,他引:3 下载免费PDF全文
M A Saubolle T E Kiehn M H White M F Rudinsky D Armstrong 《Clinical microbiology reviews》1996,9(4):435-447
Reports of the association of Mycobacterium haemophilum with disease in humans have greatly increased. At least 64 cases have now been reported, with symptoms ranging from focal lesions to widespread, systemic disease. The organism is now known to cause primarily cutaneous and subcutaneous infection, septic arthritis, osteomyelitis, and pneumonitis in patients who are immunologically compromised and lymphadenitis in apparently immunocompetent children. Underlying conditions in the compromised patients have included AIDS; renal, bone marrow, and cardiac transplantation; lymphoma; rheumatoid arthritis; marrow hypoplasia; and Crohn's disease. Reports have originated from diverse geographic areas worldwide. The epidemiology of M. haemophilum remains poorly defined; there appears to be a genetic diversity between strains isolated from different regions. The organism is probably present in the environment, but recovery by sampling has not been successful. M. haemophilum has several unique traits, including predilection for lower temperatures (30 to 32 degrees C) and requirement for iron supplementation (ferric ammonium citrate or hemin). These may in the past have compromised recovery in the laboratory. Therapy has not been well elucidated, and the outcome appears to be influenced by the patient's underlying immunosuppression. The organisms are most susceptible to ciprofloxacin, clarithromycin, rifabutin, and rifampin. Timely diagnosis and therapy require communication between clinician and the laboratory. 相似文献
32.
Detection and identification of fungi from fungus balls of the maxillary sinus by molecular techniques 下载免费PDF全文
Willinger B Obradovic A Selitsch B Beck-Mannagetta J Buzina W Braun H Apfalter P Hirschl AM Makristathis A Rotter M 《Journal of clinical microbiology》2003,41(2):581-585
The aim of this study was to find a reliable method for the detection and identification of fungi in fungus balls of the maxillary sinus and to evaluate the spectrum of fungi in these samples. One hundred twelve samples were obtained from patients with histologically proven fungal infections; 81 samples were paraffin-embedded tissue sections of the maxillary sinus. In 31 cases, sinus contents without paraffin embedding were sent for investigation. PCR amplification with universal fungal primers for 28S ribosomal DNA and amplicon identification by hybridization with species-specific probes for Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Aspergillus terreus, Aspergillus glaucus, Pseudallescheria boydii, Candida albicans, and Candida glabrata were performed for all samples. Furthermore, PCR products were sequenced. Fresh samples were also cultivated. Fungal DNA was detected in all of the fresh samples but only in 71 paraffin-embedded tissue samples (87.7%). Sequence analysis was the most sensitive technique, as results could be obtained for 28 (90.3%) fresh samples by this method in comparison to 24 (77.4%) samples by hybridization and 16 (51.6%) samples by culture. However, sequence analysis delivered a result for only 36 (50.7%) of the paraffin-embedded specimens. Hybridization showed reliable results for A. fumigatus, which proved to be the most common agent in fungus balls of the maxillary sinus. Other Aspergillus species and other genera were rarely found. 相似文献
33.
Monoclonal antibodies (MAbs) were generated against vaccinia virus, cowpox virus KR2 Brighton, monkeypox virus Copenhagen, or ectromelia virus. Pairwise epitope specificity studies by competition ELISAs identified 23 distinct antigenic sites in 19 different orthopox virus strains. Six epitopes were completely independent of each other, and 17 closely related antigenic sites formed three separate epitope complexes. As shown by immunogold electron microscopy (ELMI), all MAbs reacted with epitopes in the envelope of intracellular naked virus, 16 MAbs recognized proteins of 32, 30, 16 or 14 kDa in Western blotting (WB), and 9 MAbs neutralized virus infectivity. In rabbitpox virus (RPV) 18 epitopes were detected. A λgt11 expression library of RPV DNA was screened with the corresponding 18 MAbs. Fourteen recombinant bacteriophage clones (ph) were isolated. Cross-hybridizations of phage and RPV DNA demonstrated a reaction with the HindIII A, HindIII D, or HindIII H fragments, respectively. DNA of ph3D was related to the A25L gene, which corresponds to the A-type inclusion body gene of cowpox virus. Two phage clones contained sequences of the 14-kDa fusion protein gene (A27L gene). Ph1A contained nearly the entire 14-kDa gene encoding 4 neutralizing (neutr) and 2 nonneutr epitopes. Ph5, expressing only half of this gene product, encoded 1 nonneutr epitope. The fusion protein of vaccinia virus MVA was isolated by immune-affinity chromatography with a neutr. catching MAb. The protein formed hollow rods (ELMI) and the 6 antigenic sites that were present were identical to those expressed by Escherichia coli infected with ph1A. WB detection with a polyclonal hyperimmune serum detected protein bands of 54, 32, 30, 16, and 14 kDa. The catching MAb bound only to a 16-kDa band. The purified fusion protein induced neutralizing antibodies in mice and rabbits. 相似文献
34.
Hübner Joachim Mattutat Johann Katalinic Alexander 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2021,64(11):1463-1472
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Verlorene Lebensjahre (Years of Life Lost, YLL) sind ein aussagekräftiger, in Deutschland jedoch wenig verwendeter Indikator... 相似文献
35.
Isabel M. A. Brüggenwirth Maureen J. M. Werner René Adam Wojciech G. Polak Vincent Karam Michael A. Heneghan Arianeb Mehrabi Jürgen L. Klempnauer Andreas Paul Darius F. Mirza Johann Pratschke Mauro Salizzoni Daniel Cherqui Michael Allison Olivier Soubrane Steven J. Staffa David Zurakowski Robert J. Porte Vincent E. de Meijer all the other contributing centers the European Liver Intestine Transplant Association 《Transplant international》2021,34(10):1928-1937
High-risk combinations of recipient and graft characteristics are poorly defined for liver retransplantation (reLT) in the current era. We aimed to develop a risk model for survival after reLT using data from the European Liver Transplantation Registry, followed by internal and external validation. From 2006 to 2016, 85 067 liver transplants were recorded, including 5581 reLTs (6.6%). The final model included seven predictors of graft survival: recipient age, model for end-stage liver disease score, indication for reLT, recipient hospitalization, time between primary liver transplantation and reLT, donor age, and cold ischemia time. By assigning points to each variable in proportion to their hazard ratio, a simplified risk score was created ranging 0–10. Low-risk (0–3), medium-risk (4–5), and high-risk (6–10) groups were identified with significantly different 5-year survival rates ranging 56.9% (95% CI 52.8–60.7%), 46.3% (95% CI 41.1–51.4%), and 32.1% (95% CI 23.5–41.0%), respectively (P < 0.001). External validation showed that the expected survival rates were closely aligned with the observed mortality probabilities. The Retransplantation Risk Score identifies high-risk combinations of recipient- and graft-related factors prognostic for long-term graft survival after reLT. This tool may serve as a guidance for clinical decision-making on liver acceptance for reLT. 相似文献
36.
Michael Indermaur Daniele Casari Tatiana Kochetkova Cinzia Peruzzi Elizabeth Zimmermann Frank Rauch Bettina Willie Johann Michler Jakob Schwiedrzik Philippe Zysset 《Journal of bone and mineral research》2021,36(7):1364-1375
Osteogenesis imperfecta (OI) is an inheritable, genetic, and collagen-related disorder leading to an increase in bone fragility, but the origin of its “brittle behavior” is unclear. Because of its complex hierarchical structure, bone behaves differently at various length scales. This study aims to compare mechanical properties of human OI bone with healthy control bone at the extracellular matrix (ECM) level and to quantify the influence of the degree of mineralization. Degree of mineralization and mechanical properties were analyzed under dry conditions in 12 fixed and embedded transiliac crest biopsies (control n = 6, OI type I n = 3, OI type IV n = 2, and OI type III n = 1). Mean degree of mineralization was measured by microcomputed tomography at the biopsy level and the mineral-to-matrix ratio was assessed by Raman spectroscopy at the ECM level. Both methods revealed that the degree of mineralization is higher for OI bone compared with healthy control. Micropillar compression is a novel technique for quantifying post-yield properties of bone at the ECM level. Micropillars (d = 5 μm, h = 10 μm) were fabricated using focused ion beam milling and quasi-statically compressed to capture key post-yield properties such as ultimate strength. The qualitative inspection of the stress–strain curves showed that both OI and healthy control bone have a ductile response at the ECM level. The quantitative results showed that compressive strength is not reduced in OI bone and is increasing with OI severity. Nanoindentation measurements revealed that OI bone tends to have a higher Young's modulus, hardness, and dissipated energy compared with healthy bone. Micropillar strength and indentation modulus increased linearly and significantly (p < .0001) with mineral-to-matrix ratio. In conclusion, this study indicates that compressive mechanical properties of dry OI bone at the iliac crest are not inferior to healthy control at the ECM level and increase with mineralization. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). 相似文献
37.
Susanne Danhauser-Riedl Edith Hausmann Hans-D. Schick Rita Bender Hermann Dietzfelbinger Johann Rastetter Axel-R. Hanauske 《Investigational new drugs》1993,11(2-3):187-195
Coupling of anthracyclines to high-molecular-weight carriers may alter drug disposition and improve antitumor effects. We have performed a clinical phase I trial of doxorubicin coupled to dextran (70000 m.w.). The drug was administered as single dose i.v. every 21–28 days. Thirteen patients have received a total of 24 courses (median 2; range 1–3). At the starting dose of 40 mg/m2 doxorubicin equivalent (DOXeq), WHO grade IV thrombocytopenia was noted in 2/2 patients. WHO grade IV hepatotoxicity and WHO grade III cardiotoxicity were noted in a patient with preexisting heart disease. Five patients were treated with 12.5 mg/m2 DOXeq. Maximal toxicity at this dose level was WHO grade III thrombocytopenia and local phlebitis (WHO grade II) in 1/5 patients, elevation of alkaline phosphatase (WHO grade III) and WHO grade III vomiting in another patient. Subsequently, five patients received 20 mg/m2 DOXeq. Hepatotoxicity was noted in 5/5 patients (1 × WHO grade IV, 1 × WHO grade III). Thrombocytopenia was noted in 3/5 patients (1 × WHO grade IV, 2 × WHO grade III). At 12.5 mg/m2 DOXeq, a patient diagnosed with a malignant fibrous histiocytoma had stable disease for 4 months. Pharmacokinetic analyses of total and free doxorubicin were performed in plasma and urine. The maximum peak plasma concentration (ppc) for total DOX was 12.3 g/ml at 40 mg/m2 DOXeq. The area under the plasma concentration time curve (AUC) ranged from 28.83–80.21 g/ml*h with dose-dependent elimination half lives (t1/2: 0.02–0.87 h;1/2: 2.69–11.58 h;1/2: 41.44–136.58 h). We conclude that the maximal tolerated dose (MTD) of AD-70 using this schedule is 40 mg/m2 DOXeq. The recommended dose for clinical phase II studies is 12.5 mg/m2 DOXeq.Abbreviations ALT
Alanine Aminotransferase
- AST
Aspartate Aminotransferase
- DOX
Doxorubicin
- DOXeq
Doxorubicin Equivalent
- ECG
Electrocardiogram
- HPLC
High Pressure Liquid Chromatography
- LD10
Lethal Dose for 10% of individuals
- MTD
Maximal Tolerated Dose
- ppc
Peak Plasma Concentration
- WHO
World Health Organisation 相似文献
38.
David L O'Riordan Kevin B Lunde Johann Urschitz Karen Glanz 《Cancer epidemiology, biomarkers & prevention》2005,14(3):722-726
OBJECTIVES: To study whether a noninvasive swabbing technique can detect sunscreen use for up to 6 hours, and whether the technique can detect reapplication of sunscreen. METHODS: Thirty volunteer office workers were randomly assigned to have one of a variety of sunscreens applied using recommended application techniques, and half were randomly assigned to have sunscreen reapplied after 3 hours. Alcohol-based swabs were used to obtain a sample from participants' arm at 20 minutes, and hourly from 1 to 6 hours post-application. Absorption readings were analyzed using an UV-visible spectrophotometer. RESULTS: The swabbing technique was consistently able to distinguish the sunscreen from control swabs for up to 6 hours. The absorption readings between 20 minutes and 6 hours were significantly higher than control swabs. There were no differences between the group that had sunscreen reapplied and the group that did not. CONCLUSION: The sunscreen swabbing technique is an effective noninvasive method for detecting a variety of sunscreen products in adults over a 6-hour period. No differences in absorption readings were found with sunscreen reapplication. This procedure will be a useful adjunct to other objective measures of sun protection and UV radiation exposure, resulting in a more accurate picture of the sun protection habits of individuals. 相似文献
39.
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