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81.
cDNA arrays are a powerful tool for the identification of differentially expressed genes in malignant tumors. We used this technique to study the gene expression profiles of anaplastic large cell lymphoma (ALCL) and Hodgkin's disease (HD). Gene expression of 11 lymphoma cell lines was analyzed covering 1176 cDNA sequences. Comparing these data to the expression profiles of B- and T-lymphocytes, we identified 27 genes that were deregulated in all cell lines or in a particular entity. For the establishment of gene expression profiles the 27 genes were assigned to four groups composed of genes deregulated in (i) all lymphoma cell lines, (ii) ALCL and HD, (iii) only HD, and (iv) ALCL exclusively. Our results indicate that ALCL and HD share the differential expression of at least five genes. In addition, both entities are characterized by the differentially deregulated expression of four genes in HD and seven genes in ALCL. Because the expression profiling was performed on cell lines, further studies are needed to clarify the biological significance of the differentially expressed genes.  相似文献   
82.
To assess the role of soluble fecal substances in the elevation of fecal Candida counts in patients with antibiotic-associated diarrhea (AAD), we investigated the growth of Candida albicans in vitro in serially diluted stool fluids from patients with AAD and healthy subjects. There were significantly higher Candida albicans counts in stool fluids diluted 1:10 from AAD patients than in healthy subjects and the phosphate-buffered saline growth control, which may be due to reduced soluble Candida inhibitors and increased availability of growth factors and nutrients.  相似文献   
83.
Summary Experiments were designed to determine whether leakage of substances across the tubular epithelium, which are impermeant in the normal kidney, falsifies the measurement of glomerular filtration rate in acute renal failure. Permeability to those substances most commonly used for filtration rate determination, polyfructosan, inulin and ferrocyanide, was estimated by measuring their recoveries following perfusion through various nephron segments in haeme pigment, ischaemic and nephrotoxic models of actue renal failure. Late proximal recovery of14C ferrocyanide was only marginally decreased compared to controls, by a maximum of 6%. Distal recovery of polyfructosan,14C and3H inulin were depressed somewhat more, by a maximum of 11%. Urinary recovery of14C inulin was reduced by only 15% in kidneys showing severely restricted renal function. It is concluded that tubular leakage is not a feature of significance in the early phase of moderate acute renal failure, that ferrocyanide and inulin are reliable markers for the determination of nephron filtration rate and water reabsorption, and that the reduction in whole kidney inulin or polyfructosan clearance reflects primarily a reduction in glomerular filtration rate.  相似文献   
84.
We have previously shown that the ubiquitously expressed lysosomal cysteine protease, cathepsin L (CTSL), is essential for skin and hair follicle homeostasis. Here we examine the effect of CTSL deficiency on hair follicle development and cycling in ctsl(-/-) mice by light and electron microscopy, Ki67/terminal dUTP nick-end labeling, and trichohyalin immunofluorescence. Hair follicle morphogenesis in ctsl(-/-) mice was associated with several abnormalities. Defective terminal differentiation of keratinocytes occurred during the formation of the hair canal, resulting in disruption of hair shaft outgrowth. Both proliferation and apoptosis levels in keratinocytes and melanocytes were higher in ctsl(-/-) than in ctsl(+/+) hair follicles. The development of the hair follicle pigmentary unit was disrupted by vacuolation of differentiating melanocytes. Hair cycling was also abnormal in ctsl(-/-) mice. Final stages of hair follicle morphogenesis and the induction of hair follicle cycling were retarded. Thereafter, these follicles exhibited a truncated resting phase (telogen) and a premature entry into the first growth phase. Further abnormalities of telogen development included the defective anchoring of club hairs in the skin, which resulted in their abnormal shedding. Melanocyte vacuolation was again apparent during the hair cycle-associated reconstruction of the hair pigmentary unit. A hallmark of these ctsl(-/-) mice was the severe disruption in the exiting of hair shafts to the skin surface. This was mostly because of a failure of the inner root sheath (keratinocyte layer next to the hair shaft) to fully desquamate. These changes resulted in a massive dilation of the hair canal and the abnormal routing of sebaceous gland products to the skin surface. In summary, this study suggests novel roles for cathepsin proteases in skin, hair, and pigment biology. Principal target tissues that may contain protein substrate(s) for this cysteine protease include the developing hair cone, inner root sheath, anchoring apparatus of the telogen club, and organelles of lysosomal origin (eg, melanosomes).  相似文献   
85.
86.
We report a case involving a young female patient with Chlamydia pneumoniae myocarditis who required assist device therapy for acute heart failure. Early diagnosis was provided by endomyocardial biopsy, and tailored antibiotic therapy facilitated quick recovery of myocardial function. This is the first case to report detecting C pneumoniae as the pathogen responsible for fulminant myocarditis while the patient was still alive and to report long-term follow-up data.  相似文献   
87.
A multitude of antigens has been recently identified by screening of cDNA expression libraries derived from human tumors with autologous sera. Using a phage autoantibody assay and small panels of sera derived from cancer patients or controls it has been shown that some of these antigens display cancer-associated autoantibody responses. The diagnostic and prognostic significance of these potentially cancer-related autoantibodies remains unclear until large-scale assays are developed and serological data are available for hundreds of cancer patients and controls. The major bottleneck for the development of large-scale assays are the cloning, expression and the purification of each of the respective antigens. Due to these limitations and despite the potential clinical relevance large-scale autoantibody tests are established for only a few of these tumor antigens. Here we describe an enzyme-linked immunosorbent assay, Crude lysate ELISA (CrELISA), suitable for antigens identified by expression screening based on crude lysates of antigen-expressing bacteria. This assay permits sensitive and specific autoantibody seroscreening without the need of laborious and time-consuming cloning, expression and purification of recombinant proteins. CrELISA is robust and provides a versatile high throughput procedure for the rapid evaluation of multiple antigens in large-scale serology.  相似文献   
88.
Recently, we identified increased cathepsin X expression in H. pylori-infected gastric mucosa. Here, we describe further up-regulation in gastric cancer and report on the role of inflammatory cytokines required for cathepsin X up-regulation in H. pylori-infected gastric mucosa, as well as on consequences for cellular invasion. Biopsy specimens were taken from the antrum, corpus and cardia of H. pylori-infected and non-infected patients. Gastric cancer samples were obtained from patients undergoing gastric surgery. Cathepsin X was detected in gastric mucosa by quantitative real-time RT-PCR, western blotting and immunohistochemistry. Induction of cathepsin X expression in epithelial and inflammatory cells caused by H. pylori infection was tested in in vitro contact and non-contact co-cultures of AGS cells and monocytic cells. Patients with H. pylori gastritis showed significantly higher cathepsin X mRNA (2.5-fold) and protein (1.6-fold) expression than H. pylori-negative patients. Cathepsin X was also up-regulated in gastric cancer (3-12-fold) compared to non-neoplastic mucosa. Cathepsin X was predominantly expressed by macrophages in the mucosal stroma and in glands of the antral mucosa. In addition, tumour cells stained for cathepsin X in 26 (68%) patients with gastric carcinoma. In general, staining was significantly more common (20 vs. 6 patients) and more intense (3.55 vs. 0.83) in intestinal type gastric cancer than in the diffuse type. In vitro cell culture experiments revealed that intercellular signalling between pathogenicity island (PAI)-positive H. pylori-infected epithelial cells and macrophages via soluble factors in the culture medium seems to be responsible for increased expression of cathepsin X in monocytes. Using antisense oligonucleotides, cathepsin X up-regulation was directly associated with higher invasiveness in vitro. Although no correlation of cathepsin X expression and TNM stage was found, our study demonstrates that cathepsin X plays a role not only in the chronic inflammation of gastric mucosa but also in the tumourigenesis of gastric cancer.  相似文献   
89.
BACKGROUND: The development of occupational asthma and allergic skin reactions caused by natural rubber latex (NRL) allergy are risks for health care workers. There are few published studies to suggest that intervention programs to reduce exposure will lead to primary prevention of sensitization. OBJECTIVE: This study assesses the effects of intervention to reduce the incidence of NRL allergy in personnel working in health care facilities insured by the German statutory accident insurance company for health care workers, Berufsgenossenschaft für Gesundheitsdienst und Wohlfahrtspflege, with approximately 3 million insured employees, by switching to powder-free NRL gloves. METHODS: The timing of introduction of intervention strategies, such as education of both physicians and administrators, together with regulations demanding that health care facilities only purchase low-protein, powder-free NRL gloves are reported. We reviewed the annual numbers of reported suspected cases of NRL-caused occupational allergies and the amount and type of gloves used in German acute-care hospitals since 1986. RESULTS: The purchase of powder-free NRL examination gloves exceeded that of powdered gloves for the first time in 1998. This only became true for powder-free NRL sterile gloves 2 years later in 2000. The incidence of suspected occupational NRL allergy cases rose until 1998 and has declined steadily since. There was a 2-year lag between the beginning of the decline in the purchase of powdered NRL examination gloves and the beginning of a decline in suspected NRL-caused occupational asthma cases. CONCLUSIONS: Despite the effect of increased recognition of NRL allergies, education about NRL allergies in health care facilities combined with the introduction of powder-free gloves with reduced protein levels has been associated with a decline in the number of suspected cases of occupational allergies caused by NRL in Germany on a nationwide scale. These results clearly indicate that primary prevention of occupational NRL allergies can be achieved if these straightforward and practical interventions are properly carried out and maintained.  相似文献   
90.
Mannitol salt agar was evaluated for detection of oxacillin resistance in 136 Staphylococcus aureus isolates. All mecA-positive isolates (n = 54) were correctly categorized as oxacillin resistant by the disk diffusion test (1-μg disk; zone diameter, <16 mm); the specificity was 97.6%. Agar screening (2 μg of oxacillin per ml) revealed a sensitivity of 98.1% and a specificity of 95.1%.  相似文献   
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