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1.
Patients on maintenance haemodialysis represent a high-risk group for parenterally transmitted viral infections, such as hepatitis B, C and G. In addition to hepatitis G virus (HGV) (GBV-C) RNA, analysed in previous studies, we characterized the seroprevalence rates of antibodies to the putative E2 protein (anti-E2) of HGV in a German cohort of patients on maintenance dialysis ( n = 72) in comparison to healthy blood donors ( n = 100). The presence of anti-E2 and/or HGV RNA as indicators of present or past HGV infection could be demonstrated in 34.7% of patients and in 16% of the blood donors ( P < 0.01). The infection rates with HGV seem to increase only during the first 6 years of haemodialysis. The simultaneous presence of viraemia and anti-E2 was found very rarely in patients and controls. Therefore, the emergence of anti-E2 indicates clearance of HGV viraemia. In conclusion, patients on haemodialysis are at high risk of acquiring HGV infection, but a chronic carrier state with viraemia is rare. The risk of infection is not strictly correlated with the duration of dialysis.  相似文献   
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Journal of Neurology - The detection of antibodies to myelin oligodendrocyte glycoprotein (MOG) is fundamental for the identification of MOG antibody-associated disorders (MOGAD), and the...  相似文献   
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BACKGROUND: Molecular mechanisms involved in the pathogenesis of severe malaria caused by Plasmodium falciparum are not fully understood. Matrix metalloproteinases (MMPs) are enzymes that proteolytically degrade both the extracellular matrix and nonmatrix substances with various functions in the modulation of immune response. The key inhibitors of MMPs are the tissue inhibitors of metalloproteinases (TIMPs). METHODS: We studied levels of MMP-8, MMP-9, TIMP-1, and TIMP-2 on admission and after 24 h, using an enzyme-linked immunosorbent assay, in serum specimens from 50 Gabonese children with severe malaria, 43 children with uncomplicated malaria, and 27 healthy control children. RESULTS: Serum MMP-8 and TIMP-1 levels were significantly higher in the severe malaria and uncomplicated malaria groups, compared with those in the control group (P < .001). TIMP-1 levels were significantly higher in patients with severe malaria, compared with those in patients with uncomplicated malaria (P < .001). High TIMP-1 levels were significantly correlated with malaria severity, as determined by the simplified multiorgan dysfunction score (Spearman rank-correlation coefficient, 0.55; P < .001). CONCLUSIONS: TIMP-1 is associated with signs and symptoms of severe malaria. MMP-8 levels are elevated in patients with severe or uncomplicated P. falciparum malaria. MMPs and TIMPs may be relevant in the pathogenesis of severe malaria, either as proteolytic enzymes that degrade the extracellular matrix or as effectors and regulators of the immune response.  相似文献   
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BACKGROUND: In dilative cardiomyopathy several factors influence dyspnoea.Patients with chronic heart failure may demonstrate impairmentof breathing pattern, ventilatory drive and respiratory musclestrength, as well as reduction of ventilatory efficiency. Thepurpose of this study was to evaluate whether dilative cardiomyopathyis accompanied by changes in breathing pattern, respiratorymuscle weakness and ventilatory neural drive. METHODS: We investigated 47 patients (36 men, mean age=47·8±11·2years) with chronic heart failure due to dilative cardiomyopathy,and 30 healthy subjects (10 men, mean age=35·4±11·7years) served as controls. Patients and controls underwent evaluationof left ventricular ejection fraction by 2D echocardiography,spirometry, body plethysmography, mouth occlusion pressure andrespiratory muscle strength, as well as by submaximal treadmillexercise testing with gas exchange measurements. The patients'results were compared to controls and predicted standard normalvalues, and evaluated for differences according to the degreeof severity of functional impairment. RESULTS: Patients with dilative cardiomyopathy demonstrated a slightreduction in lung volumes (15% of the patients with obstructiveand 15% with restrictive lung function pattern) and diffusioncapacity (20·4±6·8 vs 15·4±6·7ml. min–1 . kPa–1; P<0·01). In neuraldrive, as assessed by mouth occlusion pressure, there was nosignificant difference between patients and controls. Therewas a slight but significant reduction in respiratory musclestrength, as assessed by measuring maximal inspiratory pressurein patients with dilative cardiomyopathy (6·7±2·4kPavs 8·6±3·5kPa; P<0·01). The observedchanges were more pronounced in the severe chronic heart failurepatients (with a reduction in ventilatory efficiency) whereasno relationship among indices of cardiac or respiratory functionwas found. CONCLUSION: Patients with chronic heart failure due to dilative cardiomyopathydevelop respiratory muscle weakness without changes in neuralventilatory drive, and slight changes in breathing pattern relatedto the severity of the disease.  相似文献   
5.
Granulocyte‐monocyte apheresis (GMA) is an emerging therapeutic option in active course of ulcerative colitis (UC). Appropriate GMA dose, including total number, frequency, and duration of the individual GMA session, is a matter of debate. It was the aim of the present study to evaluate the efficacy of a dose‐intensified GMA regimen in patients with moderately to severely active UC. A prospective open‐label, single‐center study was performed in 10 patients with active UC (Rachmilewitz Clinical Activity Index [CAI] ≥ 8 points; Rachmilewitz Endoscopic Index ≥ 7 points). Patients had failed to improve after treatment with steroids and/or immunomodulators. GMA was performed twice weekly for 2 h to a maximum of 10 sessions. In each GMA session, the adsorber was changed after 1 h of treatment time. Four patients achieved remission with a CAI ≤ 4 points. Three patients had a response with an improvement of CAI of ≥3 points. Three patients showed no benefit from GMA. The quality of life score determined by the inflammatory bowel disease questionnaire‐Deutschland increased by 26 points in median. First and second filters had similar efficiency in granulocyte and monocyte adsorption. No major adverse effects were observed. Dose‐intensified GMA as reported in this study provided an encouraging short‐term response rate of 70% in patients with moderately to severely active UC not responding to standard steroid or immunomodulator therapy. Although all patients relapsed not later than 16 weeks, GMA might be useful to reduce steroid and immunomodulator usage, or to delay surgery in this patient group.  相似文献   
6.
N-Chlorotaurine (NCT), a well-tolerated endogenous long-lived oxidant that can be applied topically as an antiseptic, was tested on its fungicidal activity against Scedosporium and Lomentospora, opportunistic fungi that cause severe infections with limited treatment options, mainly in immunocompromised patients. In quantitative killing assays, both hyphae and conidia of Scedosporium apiospermum, Scedosporium boydii, and Lomentospora prolificans (formerly Scedosporium prolificans) were killed by 55 mM (1.0%) NCT at pH 7.1 and 37°C, with a 1- to 4-log10 reduction in CFU after 4 h and a 4- to >6-log10 reduction after 24 h. The addition of ammonium chloride to NCT markedly increased this activity. LIVE/DEAD staining of conidia treated with 1.0% NCT for 0.5 to 3 h increased the permeability of the cell wall and membrane. Preincubation of the test fungi in 1.0% NCT for 10 to 60 min delayed the time to germination of conidia by 2 h to >12 h and reduced their germination rate by 10.0 to 100.0%. Larvae of Galleria mellonella infected with 1.0 × 107 conidia of S. apiospermum and S. boydii died at a rate of 90.0 to 100% after 8 to 12 days. The mortality rate was reduced to 20 to 50.0% if conidia were preincubated in 1.0% NCT for 0.5 h or if heat-inactivated conidia were used. Our study demonstrates the fungicidal activity of NCT against different Scedosporium and Lomentospora species. A postantifungal effect connected with a loss of virulence occurs after sublethal incubation times. The augmenting effect of ammonium chloride can be explained by the formation of monochloramine.  相似文献   
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Carotid body (CB) chemoreceptors are the main sensors detecting systemic hypoxia. Studies in animals revealed that dopamine and histamine may serve as transmitters between the chemoreceptor cells and the afferent nerve. To gain insight whether histamine and dopamine could play a role in the human CB and thus be important for the understanding of breathing disorders, we have investigated the chemosensory traits in human CBs from nine subjects of different ages obtained at autopsy. Immunohistochemistry revealed expression of histidine decarboxylase, vesicular monoamine transporter 2, histamine receptors 1 and 3 in virtually all chemosensory cells within the glomeruli of different ages. By contrast, catecholaminergic traits (tyrosine hydroxylase and vesicular monoamine transporter 1) were only detected in a subset of CB chemosensory cells at each age group while dopamine D2 receptors were expressed in the great majority of them. Our data suggest that histamine along with catecholamines may serve as transmitters between chemoreceptor cells and the afferent nerve in humans as well.  相似文献   
10.
OBJECTIVE: The apolipoprotein E (APOE) polymorphism is known to impact on various neurologic disorders and has differential effects on the immune system and on CNS repair. Previous findings concerning a possible modulation of the clinical course of MS have been inconsistent, however. METHODS: In a cross-sectional study, the authors investigated 374 patients with clinically definite MS and a disease duration of at least 3 years and related their clinical and demographic findings to the allelic polymorphism of the APOE gene. The genotype distribution of patients with MS was compared with a cohort of 389 asymptomatic, randomly selected elderly volunteers. RESULTS: The authors found no significant differences in the distribution of genotypes between patients with MS and controls. However, patients with MS with the epsilon4 allele (n = 85) had a significantly higher progression index of disability (0.46 +/- 0.4 versus 0.33 +/- 0.26; p < 0.004) and a worse ranked MS severity score (5.1 +/- 1.9 versus 5.7 +/- 1.7; p = 0.05) than their non-epsilon4 counterparts, despite significantly more frequent long-term immunotherapy in epsilon4 carriers (74% versus 58%; p < 0.007). The annual relapse rate in epsilon4 carriers (0.87 +/- 0.56) was significantly higher than in patients with MS without an epsilon4 allele (0.71 +/- 0.47; p = 0.03). CONCLUSIONS: These results suggest no effect of the APOE genotype on susceptibility to MS, but indicate an association of the APOE epsilon4 allele with a more severe course of the disease.  相似文献   
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