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1.
Update on Pneumocystis carinii f. sp. hominis Typing Based on Nucleotide Sequence Variations in Internal Transcribed Spacer Regions of rRNA Genes 总被引:6,自引:0,他引:6 下载免费PDF全文
Chao-Hung Lee Jannik Helweg-Larsen Xing Tang Shaoling Jin Baozheng Li Marilyn S. Bartlett Jang-Jih Lu Bettina Lundgren Jens D. Lundgren Mats Olsson Sebastian B. Lucas Patricia Roux Antonietta Cargnel Chiara Atzori Olga Matos James W. Smith 《Journal of clinical microbiology》1998,36(3):734-741
Pneumocystis carinii f. sp. hominis isolates from 207 clinical specimens from nine countries were typed based on nucleotide sequence variations in the internal transcribed spacer regions I and II (ITS1 and ITS2, respectively) of rRNA genes. The number of ITS1 nucleotides has been revised from the previously reported 157 bp to 161 bp. Likewise, the number of ITS2 nucleotides has been changed from 177 to 192 bp. The number of ITS1 sequence types has increased from 2 to 15, and that of ITS2 has increased from 3 to 14. The 15 ITS1 sequence types are designated types A through O, and the 14 ITS2 types are named types a through n. A total of 59 types of P. carinii f. sp. hominis were found in this study. 相似文献
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Cassandra R. OLenick Amir Baniassadi Ryan Michael Andrew Monaghan Jennifer Boehnert Xiao Yu Mary H. Hayden Christine Wiedinmyer Kai Zhang Peter J. Crank Jannik Heusinger Paige Hoel David J. Sailor Olga V. Wilhelmi 《Environmental health perspectives》2020,128(12)
Background: Despite the substantial role indoor exposure has played in heat wave–related mortality, few epidemiological studies have examined the health effects of exposure to indoor heat. As a result, knowledge gaps regarding indoor heat–health thresholds, vulnerability, and adaptive capacity persist.Objective: We evaluated the role of indoor heat exposure on mortality and morbidity among the elderly ( of age) in Houston, Texas.Methods: Mortality and emergency hospital admission data were obtained through the Texas Department of State Health Services. Summer indoor heat exposure was modeled at the U.S. Census block group (CBG) level using building energy models, outdoor weather data, and building characteristic data. Indoor heat–health associations were examined using time-stratified case-crossover models, controlling for temporal trends and meteorology, and matching on CBG of residence, year, month, and weekday of the adverse health event. Separate models were fitted for three indoor exposure metrics, for individual lag days 0–6, and for 3-d moving averages (lag 0–2). Effect measure modification was explored via stratification on individual- and area-level vulnerability factors.Results: We estimated positive associations between short-term changes in indoor heat exposure and cause-specific mortality and morbidity [e.g., circulatory deaths, (95% CI: 1.03, 1.30)]. Associations were generally positive for earlier lag periods and weaker across later lag periods. Stratified analyses suggest stronger associations between indoor heat and emergency hospital admissions among African Americans compared with Whites.Discussion: Findings suggest excess mortality among certain elderly populations in Houston who are likely exposed to high indoor heat. We developed a novel methodology to estimate indoor heat exposure that can be adapted to other U.S. locations. In locations with high air conditioning prevalence, simplified modeling approaches may adequately account for indoor heat exposure in vulnerable neighborhoods. Accounting for indoor heat exposure may improve the estimation of the total impact of heat on health. https://doi.org/10.1289/EHP6340 相似文献
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Severely elevated C‐reactive protein accompanied by prolonged high fever and leukocytosis in a healthy peripheral blood stem cell donor: an atypical granulocyte–colony‐stimulating factor reaction? 下载免费PDF全文
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Ulrike Rottensteiner Bapi Sarker Dominik Heusinger Diana Dafinova Subha N. Rath Justus P. Beier Ulrich Kneser Raymund E. Horch Rainer Detsch Aldo R. Boccaccini Andreas Arkudas 《Materials》2014,7(3):1957-1974
In addition to good mechanical properties needed for three-dimensional tissue engineering, the combination of alginate dialdehyde, gelatin and nano-scaled bioactive glass (45S5) is supposed to combine excellent cellular adhesion, proliferation and differentiation properties, good biocompatibility and predictable degradation rates. The goal of this study was to evaluate thein vitro and in vivo biocompatibility as a first step on the way to its use as a scaffold in bone tissue engineering. In vitro evaluation showed good cell adherence and proliferation of bone marrow derived mesenchymal stem cells seeded on covalently crosslinked alginate dialdehyde-gelatin (ADA-GEL) hydrogel films with and without 0.1% nano-Bioglass®(nBG). Lactate dehydrogenase (LDH)- and mitochondrial activity significantly increased in both ADA-GEL and ADA-GEL-nBG groups compared to alginate. However, addition of 0.1% nBG seemed to have slight cytotoxic effect compared to ADA-GEL. In vivo implantation did not produce a significant inflammatory reaction, and ongoing degradation could be seen after four weeks. Ongoing vascularization was detected after four weeks. The good biocompatibility encourages future studies using ADA-GEL and nBG for bone tissue engineering application. 相似文献
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Lena M. Biehl Paul G. Higgins Jannik Stemler Meyke Gilles Silke Peter Daniela Drfel Wichard Vogel Winfried V. Kern Hanna Glz Hartmut Bertz Holger Rohde Eva-Maria Klupp Philippe Schafhausen Jon Salmanton-García Melanie Stecher Julia Wille Blasius Liss Kyriaki Xanthopoulou Janine Zweigner Harald Seifert Maria J.G.T. Vehreschild 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(2)
BackgroundEvidence supporting the effectiveness of single-room contact precautions (SCP) in preventing in-hospital acquisition of vancomycin-resistant enterococci (haVRE) is limited.AimWe assessed the impact of SCP on haVRE and their transmission.MethodsWe conducted a prospective, multicentre cohort study in German haematological/oncological departments during 2016. Two sites performed SCP for VRE patients and two did not (NCP). We defined a 5% haVRE-risk difference as non-inferiority margin, screened patients for VRE, and characterised isolates by whole genome sequencing and core genome MLST (cgMLST). Potential confounders were assessed by competing risk regression analysis.ResultsWe included 1,397 patients at NCP and 1,531 patients at SCP sites. Not performing SCP was associated with a significantly higher proportion of haVRE; 12.2% (170/1,397) patients at NCP and 7.4% (113/1,531) patients at SCP sites (relative risk (RR) 1.74; 95% confidence interval (CI): 1.35–2.23). The difference (4.8%) was below the non-inferiority margin. Competing risk regression analysis indicated a stronger impact of antimicrobial exposure (subdistribution hazard ratio (SHR) 7.46; 95% CI: 4.59–12.12) and underlying disease (SHR for acute leukaemia 2.34; 95% CI: 1.46–3.75) on haVRE than NCP (SHR 1.60; 95% CI: 1.14–2.25). Based on cgMLST and patient movement data, we observed 131 patient-to-patient VRE transmissions at NCP and 85 at SCP sites (RR 1.76; 95% CI: 1.33–2.34).ConclusionsWe show a positive impact of SCP on haVRE in a high-risk population, although the observed difference was below the pre-specified non-inferiority margin. Importantly, other factors including antimicrobial exposure seem to be more influential. 相似文献
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Julian Klein Laura Kampermann Sascha Saddeler Jannik Korte Oliver Kowollik Tim Smola Stephan Schulz Gerd Bacher 《RSC advances》2021,11(54):33905
In this work the photoluminescence (PL) of CoxFe3−xO4 spinel oxide nanoparticles under pulsed UV laser irradiation (λexc = 270 nm) is investigated for varying Co/Fe ratios (x = 0.4⋯2.5). A broad emission in the green spectral range is observed, exhibiting two maxima at around 506 nm, which is dominant for Fe-rich nanoparticles (x = 0.4, 0.9), and at around 530 nm, that is more pronounced for Co-rich nanoparticles (x > 1.6). As examinations in different atmospheres show that the observed emission reacts sensitively to the presence of water, it is proposed that the emission is mainly caused by OH groups with terminal or bridging metal–O bonds on the CoxFe3−xO4 surface. Raman spectroscopy supports that the emission maximum at 506 nm corresponds to terminal OH groups bound to metal cations on tetrahedral sites (i.e., Fe3+), while the maximum around 530 nm corresponds to terminal OH groups bound to metal cations on octahedral sites (i.e., Co3+). Photoinduced dehydroxylation shows that OH groups can be removed on Fe-rich nanoparticles more easily, leading to a conversion process and the formation of new OH groups with different bonds to the surface. As such behavior is not observed for CoxFe3−xO4 with x > 1.6, we conclude that the OH groups are more stable against dehydroxylation on Co-rich nanoparticles. The higher OH stability is expected to lead to a higher catalytic activity of Co-rich cobalt ferrites in the electrochemical generation of oxygen.CoxFe3−xO4 (0.4 < x < 2.5) nanoparticles show a broad green emission induced by surface OH-groups with a lower stability regarding UV-photoinduced dehydroxylation on Fe-rich (x ≤ 1.6) nanoparticles. 相似文献
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The objective of this paper was to assess the available clinical data on the efficacy and safety of ointments containing either a bacterial culture suspension (BCS) from Escherichia coli or a combination of BCS with hydrocortisone (CAS 50-23-7) (BCS: Posterisan, and BCS + HC: Posterisan forte). The BCS is assumed to act by immunomodulation in hemorrhoidal disease and perianal eczema. Six randomized, double-blind trials are reported: three of them using BCS ointment and one using BCS + HC, against ointment base, and two trials using BCS + HC against hydrocortisone ointment alone. Patients with hemorrhoids and/or perianal eczema were included and treated over 2 weeks with weekly assessments. Efficacy parameters included score changes for burning, itching, redness and soiling as well as the investigators' overall efficacy rating. Safety was assessed from adverse drug reactions and an overall safety rating. Out of 1,070 patients (mean age 50 years), 273 received BCS and 229 BCS + HC; 568 patients were given the various controls. In the overall efficacy rating, BCS ointment was significantly superior to the ointment base in all three studies (p = 0.028, p = 0.016, and p = 0.045). Moreover, BCS + HC was superior to the ointment base (p < 0.001) and to hydrocortisone alone (p = 0.156 and p = 0.021), confirming the distinct effect of the E. coli suspension. Satisfactory results were achieved in 83% of patients after the BCS + HC combination, 77% after BCS-containing ointment, 75% after hydrocortisone ointment and 52% after ointment base. Symptom scores decreased consistently more after administration of BCS than after the ointment base (p = 0.095, p = 0.006, and p = 0.029), and likewise, the combination of BCS + HC was significantly superior to the ointment base (p < 0.001) and to hydrocortisone alone (p = 0.036 and p = 0.019). Adverse events were less frequent for BCS and BCS + HC than for the ointment base. It can therefore be concluded that ointments containing either only E. coli BCS or a combination of BCS and hydrocortisone provide significant relief in perianal eczema as well as in early stages of hemorrhoidal disease. 相似文献
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Larsen N Godt J Grunkin M Lund-Andersen H Larsen M 《Investigative ophthalmology & visual science》2003,44(2):767-771
PURPOSE: To evaluate the performance of an automated fundus photographic image-analysis algorithm in high-sensitivity and/or high-specificity segregation of patients with diabetes with untreated diabetic retinopathy from those without retinopathy. METHODS: This was a retrospective cross-sectional study of 260 consecutive nonphotocoagulated eyes in 137 diabetic patients attending routine photographic retinopathy screening. Mydriatic 60 degrees fundus photography on 35-mm color transparency film was used, with a single fovea-centered field. Routine grading was based on visual examination of slide-mounted transparencies. Reference grading was performed with specific emphasis on achieving high sensitivity. Computer-assisted automated red lesion detection was performed on digitized transparencies. RESULTS: When applied in a screening population comprising patients with diabetes with untreated diabetic retinopathy in any eye and patients with diabetes without retinopathy, the automated lesion detection correctly identified 90.1% of patients with retinopathy and 81.3% of patients without retinopathy. A per-eye analysis for methodological purposes demonstrated that the automated lesion detection could be adapted to simulate various visual evaluation strategies. When adapted at high sensitivity, the automated system demonstrated sensitivity at 93.1% and specificity at 71.6%. When adapted at high specificity the automated system demonstrated sensitivity at 76.4% and specificity at 96.6%, closely matching routine visual grading at sensitivity 76.4% and specificity 98.3%. CONCLUSIONS: Automated detection of untreated diabetic retinopathy in fundus photographs from a screening population of patients with diabetes can be made with adjustable priority settings, emphasizing high-sensitivity identification of diabetic retinopathy or high-specificity identification of absence of retinopathy, covering opposing extremes of visual evaluation strategies demonstrated by human observers. 相似文献