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21.
Shafaque Rahman Mark Davids Patricia H. P. van Hamersveld Olaf Welting Hakim Rahaoui Frank Schuren Sybren L. Meijer Ren M. van den Wijngaard Theodorus B. M. Hakvoort Wouter J. de Jonge Sigrid E. M. Heinsbroek 《Nutrients》2021,13(4)
β-glucan consumption is known for its beneficial health effects, but the mode of action is unclear. While humans and mice lack the required enzymes to digest β-glucans, certain intestinal microbes can digest β-glucans, triggering gut microbial changes. Curdlan, a particulate β-glucan isolated from Alcaligenes faecalis, is used as a food additive. In this study we determined the effect of curdlan intake in mice on the intestinal microbiota and dextran sodium sulfate (DSS)-induced intestinal inflammation. The effect of curdlan on the human intestinal microbiota was assessed using i-screen, an assay for studying anaerobic microbial interactions. Mice received oral gavage with vehicle or curdlan for 14 days followed by DSS for 7 days. The curdlan-fed group showed reduced weight loss and colonic inflammation compared to the vehicle-fed group. Curdlan intake did not induce general microbiota community changes, although a specific Bifidobacterium, closely related to Bifidobacterium choerinum, was observed to be 10- to 100-fold more prevalent in the curdlan-fed group under control and colitis conditions, respectively. When tested in i-screen, curdlan induced a global change in the microbial composition of the healthy intestinal microbiota from a human. Overall, these results suggest that dietary curdlan induces microbiota changes that could reduce intestinal inflammation. 相似文献
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Richard Leman Francisco Alvarado-Ramy Sean Pocock Neil Barg Molly Kellum Sigrid McAllister James Cheek Matthew Kuehnert 《Infection control and hospital epidemiology》2004,25(2):121-125
BACKGROUND AND OBJECTIVE: Although reports of methicillin-resistant Staphylococcus aureus (MRSA) infections without healthcare exposure are increasing, population-based data regarding nasal colonization are lacking. We assessed the prevalence of and risk factors for community-associated MRSA nasal carriage in patients of a rural outpatient clinic. DESIGN: A cross-sectional population survey was conducted through random sample and stratification by community of residence. Recent healthcare exposure (ie, hospitalization, dialysis, or healthcare occupation) and other risk factors for MRSA carriage were assessed. Cultures of the nares were performed. Community-associated MRSA was defined as MRSA carriage without healthcare exposure. SETTING: A predominantly American Indian community in Washington. PATIENTS: Those receiving healthcare from an Indian Health Service clinic. RESULTS: Of 1,311 individuals identified for study, 475 (36%) participated. Unsatisfactory culture specimens resulted in exclusion of 6 participants. In all, 128 (27.3%) of 469 participants had S. aureus. Nine (1.9%) of 469 had MRSA carriage; of these, 5 had community-associated MRSA (5 of 469; overall community-associated MRSA carriage rate, 1.1%). MRSA carriage was associated with antimicrobial use in the previous year (risk ratio [RR], 7.2; P = .04) and residence in a household of more than 7 individuals (RR, 4.5; P = .03). Pulsed-field gel electrophoresis indicated that 5 (55%) of 9 MRSA carriage isolates were closely related, including 3 (60%) of 5 that were community associated. CONCLUSIONS: Prevalence of community-associated MRSA colonization was approximately 1% in this rural, American Indian population. Community-associated MRSA colonization was associated with recent antimicrobial use and larger household. 相似文献
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Epidemiologic data suggest that an underlying genetic disposition can be detected in up to 10% of all colorectal cancer patients and autosomal dominantly inherited hereditary non-polyposis colorectal cancer (HNPCC) is the entity most frequently identified. It was described first by A. Warthin in 1895 in "Family G" and is characterized by a predisposition to an early onset of colorectal cancer and other intestinal or genitourinary tumors. We report the case of a 61-year-old woman with five different cancers. Although the strict Amsterdam Criteria were not fulfilled, molecular analysis revealed HNPCC; further genetic testing in the family confirmed that the 36-year-old and so far healthy son had inherited the germline mutation of his affected mother. Genetic testing in clinically suspected HNPCC cases is recommended for patients with colorectal cancer meeting the Amsterdam Criteria. In patients meeting one of Bethesda Criteria 2-7 without meeting the Amsterdam Criteria, germline mutation analysis is recommended only in MSI-positive tumors. 相似文献
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Tim Laussmann Ireneus Grzesiak Alexander Krest Kathrin Stirnat Sigrid Meier‐Giebing Uwe Ruschewitz Axel Klein 《Drug testing and analysis》2015,7(1):56-64
The chemical composition of a black powder confiscated by German customs was elucidated. Black powders are occasionally used as a ‘transporter’ for cocaine and are obviously especially designed to cloak the presence of the drug. The material consisting of cocaine, copper, iron, thiocyanate, and graphite was approached by analytical tools and chemical modelling. Graphite is added to the material probably with the intention of masking the typical infrared (IR) fingerprints of cocaine and can be clearly detected by powder X‐ray diffraction (XRD) and Raman spectroscopy. Cu2+ and NCS? ions, when carefully reacted with cocaine hydrochloride, form the novel compound (CocH)2[Cu(NCS)4] (CocH+ = protonated cocaine), which has been characterised by single crystal XRD, IR, NMR, UV/Vis absorption and EPR spectroscopy. Based on some further experiments the assumed composition of the original black powder is discussed. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Sigrid Carlsson Fredrik Sandin Katja Fall Mats Lambe Jan Adolfsson Pär Stattin Anna Bill-Axelson 《European journal of cancer (Oxford, England : 1990)》2013,49(7):1588-1599
PurposeRisk of suicide is increased among men with prostate cancer. We investigated this association among men with low-risk cancer, usually detected by prostate specific antigen (PSA)-testing.Patients and MethodsRelative risk (RR) of suicide was calculated by use of Poisson regression analysis within the Prostate Cancer data Base Sweden (PCBaSe) 2.0, a nation-wide, population-based database, comparing 105,736 men diagnosed with prostate cancer between 1997–2009 to 528,658 matched prostate cancer-free men.ResultsDuring the first 6 months after diagnosis, there were 38 suicides among men with prostate cancer; incidence rate 0.73 per 1000 person-years (PY) and 30 suicides in the comparison cohort; 0.11 per 1000 PY, corresponding to a RR of suicide of 6.5 (95% confidence interval (CI) 4.0–10). Risk was highest among men with distant metastases, incidence rate 1.25 per 1000 PY, RR 10 (95% CI 5.1–21) but risk was also increased for men with low-risk tumours, incidence rate difference 0.45 per 1000 PY and RR 5.2 (95% CI 2.3–12) and across categories of socioeconomic status and comorbidity. Eighteen months after diagnosis, risk of suicide had decreased to 0.27 per 1000 PY, RR 1.0 (95% CI 0.68–1.5) for low-risk prostate cancer but remained increased among men with metastases, 0.57 per 1000 PY, RR 1.8 (95% CI 1.1–2.9).ConclusionAlthough the increase in absolute risk of suicide was modest, our findings reflect the severe psychological stress that prostate cancer patients may experience after diagnosis. The increased risk of suicide observed in men with prostate cancer, including low-risk, calls for increased awareness. 相似文献
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Background
Curcumin (diferuloylmethane), the yellow pigment in the Asian spice turmeric, is a hydrophobic polyphenol from the rhizome of Curcuma longa. Because of its chemopreventive and chemotherapeutic potential with no discernable side effects, it has become one of the major natural agents being developed for cancer therapy. Accumulating evidence suggests that curcumin induces cell death through activation of apoptotic pathways and inhibition of cell growth and proliferation. The mitotic checkpoint, or spindle assembly checkpoint (SAC), is the major cell cycle control mechanism to delay the onset of anaphase during mitosis. One of the key regulators of the SAC is the anaphase promoting complex/cyclosome (APC/C) which ubiquitinates cyclin B and securin and targets them for proteolysis. Because APC/C not only ensures cell cycle arrest upon spindle disruption but also promotes cell death in response to prolonged mitotic arrest, it has become an attractive drug target in cancer therapy. 相似文献30.
Franz Pfeiffer Julia Herzen Marian Willner Michael Chabior Sigrid Auweter Maximilian Reiser Fabian Bamberg 《Zeitschrift für medizinische Physik》2013,23(3):176-185
In this review article we describe the development of grating-based X-ray phase-contrast imaging, with particular emphasis on potential biomedical applications of the technology. We review the basics of image formation in grating-based phase-contrast and dark-field radiography and present some exemplary multimodal radiography results obtained with laboratory X-ray sources. Furthermore, we discuss the theoretical concepts to extend grating-based multimodal radiography to quantitative transmission, phase-contrast, and dark-field scattering computed tomography. 相似文献