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A prospective study of 62 chemotherapy-induced neutropenic episodes in patients with acute leukaemia was conducted to determine the incidence and causes of abdominal infections, and to assess the diagnostic value of the combined use of ultrasonography (US) and microbiology. Each patient underwent US of liver, gallbladder and complete bowel before chemotherapy, on days 2-4 after the end of chemotherapy and in cases of fever, diarrhoea or abdominal pain. US was combined with a standardized clinical examination and a broad spectrum of microbiological investigations. From January to August 2001, 243 US examinations were performed. The overall incidence of abdominal infectious diseases was 17.7% (11 out of 62, 95% confidence interval (CI): 9-29%). Four patients (6.5%) developed neutropenic enterocolitis; two of them died, two survived. Bowel wall thickening (BWT) > 4 mm in these four patients ranged from 5.8 to 23.6 mm and was detected only in one patient with mucositis. In three other patients (4.8%) Clostridium difficile, and in one patient (1.6%) Campylobacter jejuni, caused enterocolitis without BWT. Cholecystitis was diagnosed in three patients (4.8%) and hepatic candidiasis was strongly suspected in one patient. Abdominal infections caused by gastroenteritis viruses, cytomegalovirus (CMV) or Cryptosporidium were not observed. We conclude that in neutropenic patients with acute leukaemia receiving chemotherapy: (i) BWT is not a feature of chemotherapy-induced mucositis and should therefore be considered as sign of infectious enterocolitis; (ii) viruses, classic bacterial enteric pathogens (Salmonella, Shigella, Yersinia, Campylobacter, Aeromonas, Vibrio subsp., enterohaemorrhagic Escherichia coli) and Cryptosporidium have a very low incidence; and (iii) abdominal infections may be underestimated when US is not used in every patient with abdominal pain.  相似文献   
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OBJECTIVES: The aim of this study was to investigate whether myocardial inflammation (MC) and endothelial activation are associated with clinically detectable endothelial dysfunction. BACKGROUND: In patients with MC, immunohistologic evaluation of myocardial biopsies demonstrates a cellular infiltrate of lymphocytes in the myocardium and endothelial activation, as indicated by enhanced expression of human leukocyte antigen (HLA)-1, HLA-DR and intercellular adhesion molecule (ICAM)-1. This chronic inflammatory process may be associated with endothelial dysfunction. METHODS: In 65 patients with suspected MC, endothelial function of the radial artery was noninvasively assessed. By means of high-resolution ultrasound, diameter changes in response to reactive hyperemia (endothelium-dependent), as compared with glyceroltrinitrate (endothelium-independent), were analyzed. In the myocardial biopsies, MC was confirmed by immunohistology in 53 patients; 12 patients with normal myocardial biopsies served as controls. Endothelial expression of HLA-1, HLA-DR and ICAM-1 was semiquantitatively evaluated by immunohistology. To minimize other factors influencing endothelial function, patients with coronary artery disease, diabetes, severely impaired left ventricular function or more than one arteriosclerotic risk factor were excluded from this study. RESULTS: Endothelial function, as determined by flow-mediated vasodilation (FMD), in patients with MC was impaired (FMD(MC) 4.28%), as compared with controls (FMD(Co) 10.10%). The severity of endothelial dysfunction in patients with MC correlated significantly with the extent of endothelial expression of HLA-1, HLA-DR and ICAM-1 in myocardial biopsies. Endothelium-independent vasodilation was not affected by MC or endothelial activation. CONCLUSIONS: Myocardial inflammation is associated with endothelial dysfunction of peripheral arteries. The severity of endothelial dysfunction correlates with the extent of endothelial activation.  相似文献   
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International Journal of Clinical Pharmacy - Background A frequent problem in ageing patients, and thus in nursing home residents, is dysphagia, affecting the ability to swallow solid dosage forms....  相似文献   
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This article comprises the development and validation of a protocol for the qualitative analysis of 61 phase I synthetic cannabinoid metabolites in urine originating from 29 synthetic cannabinoids, combining solid‐phase extraction (SPE) utilizing a reversed phase silica‐based sorbent (phenyl) with liquid chromatography–tandem mass spectrometry (LC?MS/MS). Validation was performed according to the guidelines of the German Society of Toxicological and Forensic Chemistry. Sufficient chromatographic separation was achieved within a total runtime of 12.3 minutes. Validation included specificity and selectivity, limit of detection (LOD), recovery and matrix effects, as well as auto‐sampler stability of processed urine samples. LOD ranged between 0.025 ng/mL and 0.5 ng/mL in urine. Recovery ranged between 43% and 97%, with only two analytes exhibiting recoveries below 50%. However, for those two analytes, the LODs were 0.05 ng/mL in urine. In addition, matrix effects between 81% and 185% were determined, whereby matrix effects over 125% were observed for 10 non‐first‐generation synthetic cannabinoid metabolites. The developed method enables the rapid and sensitive detection of synthetic cannabinoid metabolites in urine, complementing the spectrum of existing analytical tools in forensic case work. Finally, application to 61 urine samples from both routine and autopsy case work yielded one urine sample that tested positive for ADB‐PINACA N‐pentanoic acid.  相似文献   
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Cx43, a major cardiac connexin, forms precursor hemichannels that accrue at the intercalated disc to assemble as gap junctions. While gap junctions are crucial for electrical conduction in the heart, little is known about the potential roles of hemichannels. Recent evidence suggests that inhibiting Cx43 hemichannel opening with Gap19 has antiarrhythmic effects. Here, we used multiple electrophysiology, imaging, and super-resolution techniques to understand and define the conditions underlying Cx43 hemichannel activation in ventricular cardiomyocytes, their contribution to diastolic Ca2+ release from the sarcoplasmic reticulum, and their impact on electrical stability. We showed that Cx43 hemichannels were activated during diastolic Ca2+ release in single ventricular cardiomyocytes and cardiomyocyte cell pairs from mice and pigs. This activation involved Cx43 hemichannel Ca2+ entry and coupling to Ca2+ release microdomains at the intercalated disc, resulting in enhanced Ca2+ dynamics. Hemichannel opening furthermore contributed to delayed afterdepolarizations and triggered action potentials. In single cardiomyocytes, cardiomyocyte cell pairs, and arterially perfused tissue wedges from failing human hearts, increased hemichannel activity contributed to electrical instability compared with nonfailing rejected donor hearts. We conclude that microdomain coupling between Cx43 hemichannels and Ca2+ release is a potentially novel, targetable mechanism of cardiac arrhythmogenesis in heart failure.  相似文献   
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ERCC1-XPF is a multifunctional endonuclease involved in nucleotide excision repair (NER), interstrand cross-link (ICL) repair, and DNA double-strand break (DSB) repair. Only two patients with bi-allelic ERCC1 mutations have been reported, both of whom had features of Cockayne syndrome and died in infancy. Here, we describe two siblings with bi-allelic ERCC1 mutations in their teenage years. Genomic sequencing identified a deletion and a missense variant (R156W) within ERCC1 that disrupts a salt bridge below the XPA-binding pocket. Patient-derived fibroblasts and knock-in epithelial cells carrying the R156W substitution show dramatically reduced protein levels of ERCC1 and XPF. Moreover, mutant ERCC1 weakly interacts with NER and ICL repair proteins, resulting in diminished recruitment to DNA damage. Consequently, patient cells show strongly reduced NER activity and increased chromosome breakage induced by DNA cross-linkers, while DSB repair was relatively normal. We report a new case of ERCC1 deficiency that severely affects NER and considerably impacts ICL repair, which together result in a unique phenotype combining short stature, photosensitivity, and progressive liver and kidney dysfunction.  相似文献   
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