207 research outputs found
Monitoring of rotavirus infection in a paediatric hospital by RNA electrophoresis
During the spring of 1987 and the autumn of 1988, stool specimens were collected from infants and young children in the paediatric unit at H. F. Verwoerd Hospital, Pretoria, and examined for the presence of rotaviruses to assess the potential for hospital-acquired infection in the paediatric wards. Stool samples were also collected from children admitted to the hospital for causes unrelated to gastro-enteritis to investigate the possible asymptomatic carriage of rotavirus in this population. Hospital-acquired rotavirus infection was detennined in only 9% of cases. Very little asymptomatic carriage of the virus was identified. Electrophoretic analysis of the rotavirus strains showed that the majority of the infections (20 of 42) were associated with a particular strain with a long RNA profile, while 7 minor strains co-circulated (5 with a long electrophoretype and 2 with a short one). An apparent small outbreak of nosocomial infection with a single strain was observed to occur in one of the paediatric wards during the spring and early summer
The Reconstruction of a Buried Maas River Landscape near Lomm, (Limburg, The Netherlands) Using a Multi-Disciplinary Approach; Human Adaption to Landscape Changes
Ancient Yersinia pestis genomes provide no evidence for the origins or spread of the Justinianic Plague.
A seventeenth-centuryMycobacterium tuberculosisgenome supports a Neolithic emergence of theMycobacterium tuberculosiscomplex
BACKGROUND: Although tuberculosis accounts for the highest mortality from a bacterial infection on a global scale, questions persist regarding its origin. One hypothesis based on modern Mycobacterium tuberculosis complex (MTBC) genomes suggests their most recent common ancestor followed human migrations out of Africa approximately 70,000 years before present. However, studies using ancient genomes as calibration points have yielded much younger dates of less than 6000 years. Here, we aim to address this discrepancy through the analysis of the highest-coverage and highest-quality ancient MTBC genome available to date, reconstructed from a calcified lung nodule of Bishop Peder Winstrup of Lund (b. 1605-d. 1679). RESULTS: A metagenomic approach for taxonomic classification of whole DNA content permitted the identification of abundant DNA belonging to the human host and the MTBC, with few non-TB bacterial taxa comprising the background. Genomic enrichment enabled the reconstruction of a 141-fold coverage M. tuberculosis genome. In utilizing this high-quality, high-coverage seventeenth-century genome as a calibration point for dating the MTBC, we employed multiple Bayesian tree models, including birth-death models, which allowed us to model pathogen population dynamics and data sampling strategies more realistically than those based on the coalescent. CONCLUSIONS: The results of our metagenomic analysis demonstrate the unique preservation environment calcified nodules provide for DNA. Importantly, we estimate a most recent common ancestor date for the MTBC of between 2190 and 4501 before present and for Lineage 4 of between 929 and 2084 before present using multiple models, confirming a Neolithic emergence for the MTBC
Bioelectrical Impedance Analysis Overestimates Fat-Free Mass in Breast Cancer Patients Undergoing Treatment
Background: Bioelectrical impedance analysis (BIA) is commonly used to assess fat-free mass (FFM) and fat mass (FM) in breast cancer patients. However, because of the prevalence of overweight, obesity and variable hydration status in these patients, assumptions for existing prediction equations developed in healthy adults may be violated, resulting in inaccurate body composition assessment. Methods:We measured whole-body FFM using single-frequency BIA (50 kHz) and dual-energy x-ray absorptiometry (DXA) in 48 patients undergoing treatment for breast cancer.We applied raw BIA data to 18 previously published FFM prediction
equations (FFMBIA) and compared these estimates to DXA (FFMDXA; reference method). Results: On average, patients were 52 ± 10 (mean ± SD) years of age and overweight (body mass index: 27.5 ± 5.5 kg/m2; body fat by DXA: 40.1% ± 6.6%). Relative to DXA, BIA overestimated FFM by 4.1 ± 3.4 kg (FFMDXA: 42.0 ± 5.9 kg; FFMBIA: 46.1 ± 3.4 kg). Individual equation-generated predictions of FFMBIA ranged from 39.6 ± 6.7 to 52.2 ± 5.6 kg, with 16 equations overestimating and 2 equations underestimating FFMBIA compared with FFMDXA. Based on equivalence testing, no equation-generated estimates were equivalent
to DXA. Conclusion: Compared with DXA, BIA overestimated FFM in breast cancer patients during treatment. Although several equations performed better than others, none produced values that aligned closely with DXA. Caution should be used when interpreting BIA measurements in this clinical population, and future studies should develop prediction equations specific to breast cancer patients. (Nutr Clin Pract. 2019;00:1–12)Financial disclosure: This work was funded by a Canadian Institutes of Health Research grant, an Ontario Ministry of Research and Innovation Early Researcher Award, and the Canadian Foundation for Innovation (all to M. Mourtzakis)
Cerebral Autoregulation Assessment Using the Near Infrared Spectroscopy 'NIRS-Only' High Frequency Methodology in Critically Ill Patients:A Prospective Cross-Sectional Study
Impairments in cerebral autoregulation (CA) are related to poor clinical outcome. Near infrared spectroscopy (NIRS) is a non-invasive technique applied to estimate CA. Our general purpose was to study the clinical feasibility of a previously published 'NIRS-only' CA methodology in a critically ill intensive care unit (ICU) population and determine its relationship with clinical outcome. Bilateral NIRS measurements were performed for 1-2 h. Data segments of ten-minutes were used to calculate transfer function analyses (TFA) CA estimates between high frequency oxyhemoglobin (oxyHb) and deoxyhemoglobin (deoxyHb) signals. The phase shift was corrected for serial time shifts. Criteria were defined to select TFA phase plot segments (segments) with 'high-pass filter' characteristics. In 54 patients, 490 out of 729 segments were automatically selected (67%). In 34 primary neurology patients the median (q1-q3) low frequency (LF) phase shift was higher in 19 survivors compared to 15 non-survivors (13° (6.3-35) versus 0.83° (-2.8-13), p = 0.0167). CA estimation using the NIRS-only methodology seems feasible in an ICU population using segment selection for more robust and consistent CA estimations. The 'NIRS-only' methodology needs further validation, but has the advantage of being non-invasive without the need for arterial blood pressure monitoring
Analysis of 3800-year-old Yersinia pestis genomes suggests Bronze Age origin for bubonic plague
该论文通过对青铜器时代的两个鼠疫杆菌分离株进行测序,深入剖析了鼠疫杆菌的历史。德国、俄罗斯、中国和瑞士等多国研究员共同参与了研究。这篇论文的第一作者是德国马克斯-普朗克研究所的考古遗传学专家Maria Spyrou。她和同事从俄罗斯墓穴中埋葬的九名古代人的牙齿样本入手,发现有两人感染鼠疫杆菌。之后,他们从这些个体中分离出距今约3800年的病原菌。在这项新研究中,研究人员利用液相捕获和Illumina鸟枪法测序技术,对青铜器时代的一名男子(RT5)的鼠疫杆菌和人类宿主序列进行测序,其中鼠疫杆菌基因组的平均覆盖度达到32倍。同时,他们还对另一名感染个体(RT6)的分离株进行测序,平均覆盖度为1.9倍。系统发育分析表明,RT5和RT6分离株是共同谱系的一部分,这个谱系的祖先是史上三次瘟疫大流行的罪魁祸首。除了众所周知的中世纪欧洲瘟疫大流行,鼠疫杆菌还曾造成公元6世纪的查士丁尼瘟疫和19世纪的中国大规模鼠疫。
马克斯-普朗克人类历史科学研究所的古病理学专家Kirsten Bos表示,这些结果表明“具有传播潜力的瘟疫存在的时间比我们想象得更久。”Bos是这篇论文的通讯作者之一。【Abstract】The origin of Yersinia pestis and the early stages of its evolution are fundamental subjects of investigation given its high virulence and mortality that resulted from past pandemics. Although the earliest evidence of Y. pestis infections in humans has been identified in Late Neolithic/Bronze Age Eurasia (LNBA 5000–3500y BP), these strains lack key genetic components required for flea adaptation, thus making their mode of transmission and disease presentation in humans unclear. Here, we reconstruct ancient Y. pestis genomes from individuals associated with the Late Bronze Age period (~3800 BP) in the Samara region of modern-day Russia. We show clear distinctions between our new strains and the LNBA lineage, and suggest that the full ability for flea-mediated transmission causing bubonic plague evolved more than 1000 years earlier than previously suggested. Finally, we propose that several Y. pestis lineages were established during the Bronze Age, some of which persist to the present day.We thank Cosimo Posth, Marcel Keller, Michal Feldman and Wolfgang Haak for useful insights to the manuscript, as well as Alexander Immel and Stephen Clayton for computational support. In addition, we are thankful to Guido Brandt, Antje Wissgott and Cäcilia Freund for laboratory support. M.A.S., A.H., K.I.B. and J.K. were supported by the ERC starting grant APGREID, and by the Max Planck Society. C.C.W. was supported by the Max Planck Society and the Nanqiang Outstanding Young Talents Program of Xiamen University. D.K. was supported by a Marie Heim-Vögtlin grant from the Swiss National Science Foundation
Efficacy and immunogenicity of two or three dose rotavirus-vaccine regimen in South African children over two consecutive rotavirus-seasons : a randomized, double-blind, placebo-controlled trail
BACKGROUND: Human rotavirus vaccine (HRV; i.e., Rotarix) reduced the incidence of severe rotavirus gastroenteritis (RVGE) by 77% (95% Conficence interval: 56% to 88%) during the first year of life in South Africa. Persistence of HRV-derived protection against RVGE during subsequent rotavirus seasons, although evident in industrialized settings, remains to be established in African settings. This study reports on the efficacy of HRV against server RGVE over two consecutive rotavirus seasons in South African children. METHODS: A prospective, double-blind, placebo controlled multi-centered trail in South Afria and Malawi randomly assigned infants in a 1:1:1 ration to receive either two (10 and 14 weeks; HRV_2D) or three (6, 10 and 14 weeks; HRV_3D) doses of HRV or placebo. The primary analysis involved pooling of HRV_2D and HRV_3D arms. Episodes of gastroenteritis caused by wild-type rotavirus were identified through active follow-up surveillance and graded by the Vesikari scale. RESULTS: 1,339 infants (447 in the HRV_2D group, 447 in the HRV_3D group and 445 in the placebo group) were enrolled in Year 2 of the study, including 1,035 (77.3%) who were followed up over two consecutive rotavirus seasons (i.e., Cohort 2 subjects). Rotarix was associated with ongoing protection against severe RVGE, preventing 2.5 episodes per 100 vaccinated children over two consecutive rotavirus seasons; vaccine efficacy: 59% (95% Confidence interval: 1 to 83). An exploratory analysis indicated better immunogenicity (among Cohort 1 subjects) and a higher point-efficacy estimate over two seasons in the HRV_3D compared to HRV_2D arms of the study in Cohort 2 subjects. CONCLUSION: Rotarix is associated with significant reductions in servere gastroenteritis episodes through 2 years of life among South African children. Further research is needed to determine the optimal dosing schedule of Rotarix in providing long-term protection against rotavirus illness in African children.GAVI Alliance and GlaxoSmithKline (GSK) Biologicals, Rixensart,
Belgium.http://www.elsevier.com/locate/vaccin
SWITCH : A randomised, sequential, open-label study to evaluate the efficacy and safety of Sorafenib-sunitinib versus Sunitinib-sorafenib in the treatment of metastatic renal cell cancer
Background
Understanding how to sequence targeted therapies for metastatic renal
cell carcinoma (mRCC) is important for maximisation of clinical benefit.
Objectives
To prospectively evaluate sequential use of the multikinase inhibitors sorafenib followed by sunitinib (So-Su) versus sunitinib followed by sorafenib (Su-So) in patients with mRCC.
Design, setting, and participants
The multicentre, randomised, open-label, phase 3 SWITCH study assessed So-Su versus Su-So in patients with mRCC without prior systemic therapy, and stratified by Memorial Sloan Kettering Cancer Center risk score (favourable or intermediate).
Intervention
Patients were randomised to sorafenib 400 mg twice daily followed, on progression or intolerable toxicity, by sunitinib 50 mg once daily (4 wk on, 2 wk off) (So-Su), or vice versa (Su-So).
Outcome measurements and statistical analysis
The primary endpoint was improvement in progression-free survival (PFS) with So-Su versus Su-So, assessed from randomisation to progression or death during second-line therapy. Secondary endpoints included overall survival (OS) and safety.
Results and limitations
In total, 365 patients were randomised (So-Su, n = 182; Su-So, n = 183). There was no significant difference in total PFS between So-Su and Su-So (median 12.5 vs 14.9 mo; hazard ratio [HR] 1.01; 90% confidence interval [CI] 0.81–1.27; p = 0.5 for superiority). OS was similar for So-Su and Su-So (median 31.5 and 30.2 mo; HR 1.00, 90% CI 0.77–1.30; p = 0.5 for superiority). More So-Su patients than Su-So patients reached protocol-defined second-line therapy (57% vs 42%). Overall, adverse event rates were generally similar between the treatment arms. The most frequent any-grade treatment-emergent first-line adverse events were diarrhoea (54%) and hand-foot skin reaction (39%) for sorafenib; and diarrhoea (40%) and fatigue (40%) for sunitinib.
Conclusions
Total PFS was not superior with So-Su versus Su-So. These results demonstrate that sorafenib followed by sunitinib and vice versa provide similar clinical benefit in mRCC
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