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1.
Renal fibrosis is a hallmark of progressive kidney disease and is characterized by an accumulation of extracellular-matrix-synthesizing cells in the glomerulus and tubulointerstitium. This population of myofibroblast-like cells (MFLC) is heterogeneous. It has been experimentally shown, for example, that tubular epithelial cells could change their phenotype into MFLC under certain circumstances, a process called epithelial-mesenchymal transdifferentiation. However, MFLC may also originate from other sources. Therefore, we examined whether endothelial cells (EDC) are able to transdifferentiate into MFLC in vitro. We compared potential differences between syngeneic tubular epithelial cells (EPC) and EDC during transdifferentiation into MFLC using bovine and porcine EDC isolated from pulmonary arteries, and glomerular capillaries. Renal tubular EPC were prepared from bovine renal cortical tissue by collagenase digestion and isolation from homogeneous cell monolayers. Bovine renal tubular EPC stained positive for cytokeratin. Furthermore, tubular EPC selectively incorporated labeled bovine serum albumin, a typical property of differentiated renal tubular cells. EDC were characterized by the absence of epithelial markers (e.g. cytokeratin), but stained positive for vWF. The transdifferentiation of EDC into MFLC occurs sequentially in two steps: First, by a rapid reversible transformation in postconfluent or clonal cultures without the need of cytokine stimulation and second, by a prolonged secondary step in the presence of the transformation-accelerating cytokines and the absence of adherently growing EDC. Thus, EDC that are able to sprout can also irreversibly transdifferentiate into MFLC. On the other hand, prolonged incubation of EPC in the presence of cytokines such as transforming growth factor-beta1 and tumor necrosis factor-alpha leads only to a very small number of MFLC without the ability to further proliferate. Our in vitro data suggest that EDC can more easily transdifferentiate into MFLC than syngeneic renal tubular EPC. 相似文献
2.
Terreehorst I Duivenvoorden HJ Tempels-Pavlica Z Oosting AJ de Monchy JG Bruijnzeel-Koomen CA Post MW Gerth van Wijk R 《Allergy》2002,57(10):919-925
BACKGROUND: Allergic rhinitis, asthma or the atopic eczema/dermatitis syndrome (AEDS) may independently impair quality of life in patients. However, although many allergic patients may suffer from more than one disorder, the effect of concomitant disease -- in particular, the impact of AEDS -- is largely unknown. As part of a large multicenter clinical trial on the efficacy of mattress casings in house-dust mite (HDM) allergy, generic quality of life in a mixed population of 224 subjects with rhinitis (n = 198) and/or asthma (n = 111) and/or AEDS (n = 64) was studied. The study aimed to estimate quality of life impairment in these atopic patients and to address the question/issue of whether one atopic disorder goes beyond other existing allergic diseases, thereby causing further impairment to quality of life. METHODS: Generic quality of life was assessed by SF-36. Quality of life in the atopic group was compared with a Dutch norm population. Multiple linear regression was used to determine the effects of disease (i.e. the presence of allergic rhinitis, asthma or AEDS) or disease severity, as assessed by visual analog scores (VAS) for asthma, rhinitis, VAS sleeplessness and VAS itching being considered as major symptoms in AEDS on SF-36 domains. RESULTS: Compared to the norm group, atopic patients were impaired in: physical functioning; role physical functioning; general health; vitality; and social functioning. The diagnosis of asthma was negatively associated with the SF-36 subscales for physical functioning (P = 0.02), and general health (P < 0.01). In line with these findings, asthma severity (VAS asthma) was negatively associated with physical functioning (P < 0.01), role physical functioning (P < 0.01), general health (P < 0.0.1), social functioning (P = 0.01), emotional functioning (P = 0.01), and vitality (P = 0.01). VAS sleeplessness had significant negative effect on role physical functioning (P < 0.01), bodily pain (P < 0.01), General health (P = 0.01), mental health (P < 0.01), social functioning (P < 0.01), and vitality (P < 0.01). In contrast, neither the diagnosis of allergic rhinitis or AEDS, nor VAS itching as an outcome parameter of AEDS, exerted additional effects on the SF-36 domains. CONCLUSIONS: Patients with atopic disease based on HDM allergy may have impaired quality of life. The majority of these patients have allergic rhinitis. The (co)existence of asthma, expressed in terms of diagnostic criteria or symptom severity, or the presence of sleep disorders as a consequence of AEDS, may further impair quality of life. 相似文献
3.
Terreehorst I Duivenvoorden HJ Tempels-Pavlica Z Oosting AJ de Monchy JG Bruijnzeel-Koomen CA van Wijk RG 《Allergy》2005,60(7):888-893
BACKGROUND: Environmental control has been put forward as an integral part of the management of house dust mite (HDM) allergy in sensitized patients. To validate this statement allergic disorders involved in HDM allergy--allergic asthma, rhinitis and atopic eczema/dermatitis syndrome (AEDS)--should be taken together and studied in terms of the efficacy of environmental control. Because a generic quality of life questionnaire exceeds the border of disease, this may be used as major outcome parameter. RESEARCH OBJECTIVE: To study the effects of bedding encasings in HDM allergic patients with asthma, rhinitis and AEDS. MATERIAL AND METHODS: A total of 224 adult HDM allergic patients with rhinitis and/or asthma and/or dermatitis were randomly allocated impermeable or nonimpermeable encasings for mattress, pillow and duvet. Short form 36 (SF-36) was filled in at baseline and after 12 months. Results: Lower physical (P = 0.01) and emotional (P < 0.001) sumscores were seen in females. Also, the presence of asthma resulted in lower physical sumscore (P = 0.01). However, no effect was seen of encasings on either sumscore. CONCLUSION: Bedding encasings do not improve quality of life in a mixed population of subjects with combinations with rhinitis, asthma and atopic dermatitis and sensitized to HDMs. 相似文献
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Direct detection of influenza virus antigen in nasopharyngeal specimens by direct enzyme immunoassay in comparison with quantitating virus shedding. 总被引:2,自引:0,他引:2 下载免费PDF全文
We developed a direct enzyme immunoassay [EIA; Enzygnost Influenza A(Ag) and Enzygnost Influenza B(Ag)] for the direct detection of influenza A and B virus antigens in nasopharyngeal secretion specimens (NPS). The test is performed without sonification of specimens, and results are obtained within 4 h. A direct comparison between direct EIA and quantitation of virus shedding for influenza A and B virus antigen detection was carried out. A total of 210 NPS and 98 nasopharyngeal wash specimens (NPW) were investigated. We isolated influenza A viruses from 79 (37.6%) of 210 NPS; of these 79 cell-culture-positive NPS, 70 (88.6%) were also positive by direct EIA. Of 29 (13.8%) NPS from which influenza B virus was isolated, 24 (82.8%) NPS were positive by direct EIA. Virus shedding was determined quantitatively in 48 NPS from patients with influenza A and in 24 NPS from patients with influenza B. Only a crude correlation between optical density values and virus concentrations was observed. Detection of influenza virus antigens in NPS by direct EIA showed sensitivities of 89.7% for influenza A virus and 87.9% for influenza B virus and specificities of 99.3% for influenza A virus and 100% for influenza B virus. With direct EIA, all NPW were negative for influenza A virus, although virus was isolated from 21 (21.4%) NPW. Of 15 NPW from which influenza B virus was isolated, 7 showed positive results in direct EIA. In addition, direct EIA is suitable for detecting influenza A and B viruses in cell cultures before the appearance of any cytopathic effects and can be used as a cell culture confirmation test. 相似文献
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7.
Cerebrospinal anandamide levels are elevated in acute schizophrenia and are inversely correlated with psychotic symptoms. 总被引:7,自引:0,他引:7
Andrea Giuffrida F Markus Leweke Christoph W Gerth Daniela Schreiber Dagmar Koethe Johannes Faulhaber Joachim Klosterk?tter Daniele Piomelli 《Neuropsychopharmacology》2004,29(11):2108-2114
The endocannabinoids are a family of bioactive lipids that activate CB1 cannabinoid receptors in the brain and exert intense emotional and cognitive effects. Here, we have examined the role of endocannabinoid signaling in psychotic states by measuring levels of the endocannabinoid anandamide in cerebrospinal fluid (CSF) of acute paranoid-type schizophrenic patients. We found that CSF anandamide levels are eight-fold higher in antipsychotic-naive first-episode paranoid schizophrenics (n = 47) than healthy controls (n = 84), dementia patients (n = 13) or affective disorder patients (n = 22). Such an alteration is absent in schizophrenics treated with 'typical' antipsychotics (n = 37), which antagonize dopamine D2-like receptors, but not in those treated with 'atypical' antipsychotics (n = 34), which preferentially antagonize 5HT(2A) receptors. Furthermore, we found that, in nonmedicated acute schizophrenics, CSF anandamide is negatively correlated with psychotic symptoms (rS = -0.452, P = 0.001). The results suggest that anandamide elevation in acute paranoid schizophrenia may reflect a compensatory adaptation to the disease state. 相似文献
8.
C. L. de Mol R. Gerth van Wijk P. M. van Hagen P. L. A. van Daele 《Hematology (Amsterdam, Netherlands)》2017,22(9):544-547
Objectives: Systemic mastocytosis (SM) is a myeloproliferative disease characterized by the accumulation of aberrant mast cells. Since advanced subtypes of SM can lead to organ dysfunction and shortened survival, timely recognition of progressive disease is important for the adequate treatment of SM patients.Methods: Here, we report the results of our cohort study on the value of routine abdominal ultrasonography for the detection of progression of indolent systemic mastocytosis (ISM).Results: We included 88 patients with ISM, of whom 9 developed new hepatosplenomegaly during follow-up. In this group, the median serum tryptase level increased by 11.60?μg/l, compared with a decrease of ?0.20?μg/l in the 79 patients with unchanged ultrasonography results (p?=?0.016). A change in liver and/or spleen size never led to a change in clinical classification, nor management.Discussion: Based on the finding that a change in ultrasonography findings did not correlate to disease progression in general, it appears that isolated hepatosplenomegaly does not have prognostic implications in patients with ISM.Conclusions: Routine abdominal ultrasonography is redundant in the follow-up of patients with ISM. A combination of physical examination with serum tryptase levels can be used to screen for hepatosplenomegaly. 相似文献
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10.
Antihypertensive persistence and drug class 总被引:2,自引:0,他引:2