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51.
The receptor for urokinase plasminogen activator (uPA-R, CD87) is a glycosylphosphatidylinositol (GPI)-anchored 50 to 65 kD glycoprotein that, by regulating membrane-associated plasmin activity, may facilitate the invasion of inflammatory and malignant cells. Certain other GPI-anchored glycoproteins are shed from the cell membrane and exist as soluble products in vitro and in vivo. To determine if uPA-R undergoes a similar phenomenon, we have developed a sensitive enzyme- linked immunoabsorbent assay (ELISA) (using a rabbit antiserum as both capture and detection reagents) to measure the quantity of soluble uPA- R (suPA-R) in tissue culture supernatants and biologic fluids. Using this ELISA, we have detected suPA-R in the culture supernatants of U- 937 cells and human monocytes stimulated in vitro by certain soluble inflammatory mediators (Sitrin et al, Blood 84:1268, 1994; Mizukami et al., Clin Res 42:115A, 1994). To determine if suPA-R exists in vivo, we have screened the plasma of 20 normal volunteers (mean +/- SD, 3 +/- 3 ng/mL; median, 2 ng/mL; range, 1 to 11 ng/mL [serum values slightly higher]); the plasma of 13 ICU patients with clinical sepsis syndrome (mean +/- SD, 30 +/- 11 ng/mL; median, 11 ng/mL; range, 4 to 221 ng/mL); and the extravascular fluids (pleural, pericardial, and peritoneal) of 84 individuals with presumed inflammatory or malignant conditions (mean +/- SD, 21 +/- 39 ng/mL; median, 10 ng/mL; range, 2 to 253 ng/mL). Among the latter specimens, most were inflammatory exudates (only six were malignant by positive cytology) with the highest quantities of suPA-R associated with neutrophilic exudates. The solubility of suPA-R contained within these fluids was confirmed by reanalysis after ultracentrifugation to remove particulate material. When tested in a uPA ligand capture ELISA, representative specimens of extravascular body fluids and sepsis plasma contained suPA-R capable of binding uPA ligand (generally representing a small fraction of the immunoreactive material). We conclude from these data that suPA-R is immunologically detectable in vitro and in vivo with high concentrations of receptor found under conditions of inflammatory stimulation. The possibility of suPA-R's biologic activity is suggested by its partial retention of ligand binding capacity.  相似文献   
52.
Bodine  DM; Seidel  NE; Orlic  D 《Blood》1996,88(1):89-97
We have examined the repopulating ability of bone marrow and peripheral blood cells collected immediately and at intervals after treatment of donor mice with the combination of granulocyte colony-stimulating factor (G-CSF) and stem cell factor (SCF). Using a competitive repopulation assay we showed that the repopulating ability of peripheral blood cells was highest immediately after cytokine treatment and declined to normal levels within 6 weeks of the termination of treatment with G-CSF and SCF. In contrast the repopulating ability of bone marrow cells was low immediately after cytokine treatment and increased to levels that were 10-fold or more greater than marrow from untreated mice by 14 days after termination of treatment with G-CSF and SCF. This high level of repopulating activity declined to normal levels by 6 weeks after termination of treatment with G-CSF and SCF. The high level of repopulating ability was confirmed by injecting cells from G- CSF- and SCF-treated donors into unconditioned recipients. Peripheral blood cells collected immediately after treatment with G-CSF and SCF engrafted into unconditioned mice sevenfold better than an equivalent number of bone marrow cells from untreated mice. Likewise, bone marrow cells collected 14 days after treatment of the donor animal with G-CSF and SCF engrafted at 10-fold higher levels than an equivalent number of bone marrow cells from untreated mice. We conclude that the treatment of donor mice with G-CSF and SCF causes a transient increase in the repopulating ability of peripheral blood and later of bone marrow. These observations may have applications to clinical hematopoietic stem cell transplantation.  相似文献   
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54.
It is essential for youth with chronic health conditions like spina bifida (SB) to develop self‐management skills to combat vulnerability, achieve self‐sufficiency, and transition to adulthood. The purpose of this qualitative study was to describe the experience of self‐management in 31 adolescent women with SB. Three themes emerged from this study: (1) opportunities to engage in self‐management activities—knowledge, skills, and aspirations; (2) dance of individuation—parental impact on self‐management; and (3) advocacy within self‐management—confronting discrimination and stigma. The findings indicate that assessment and interventions to enhance self‐management in adolescent women with SB are critical for supporting the range of condition‐related and life skills needed for a transition to adulthood and independent living.  相似文献   
55.
BACKGROUND: The cytokine observed most often in atopic dermatitis (AD) is IL-4, but a role for IL-5 and IFN-gamma in the late and delayed phase reactions has been suggested. In AD with head, neck and shoulder distribution, hypersensitivity to saprophytic yeasts is an important pathogenetic factor. The yeast allergens include both the mannan polysaccharides and the proteins. Mannans are major cross-reacting allergens likely to be involved in the pathogenesis of AD. OBJECTIVE: To characterize the humoral, lymphoproliferative and cytokine (IL-2, 4, 5 and IFN-gamma) responses of peripheral blood mononuclear cells (PBMCs) induced by Candida albicans mannan and protein antigens in AD. METHODS: Fifteen AD patients and seven healthy controls were included. Ficoll-isolated PBMCs were stimulated by PHA and laboratory-generated mannan and protein extracts of C. albicans. Lymphocyte proliferation was measured and cytokine production was studied by ELISA. The antigen-specific IgG and IgE antibodies were analysed by ELISA and nitrocellulose RAST. RESULTS: In AD mannan (P < 0.005) and protein (P < 0.002), specific IgE levels were higher than in healthy controls. Both mannan and protein-specific lymphoproliferations (both: P < 0.02) were higher in AD than in healthy controls. Mannan, but not protein, induced long lasting IL-2 and IL-4 productions from 24 h lasting up to 66-96 h and IL-5 and IFN-gamma productions with elevated levels at 66 and 96 h. The mannan-induced IL-2 (P = 0.015) and IFN-gamma (P < 0.005) were increased in AD as compared with healthy controls. Significant correlations were seen between the protein-induced proliferation responses and both serum total IgE (r = 0.59, P < 0.01) and protein-specific IgE (r = 0.65, P < 0.005). The mannan-induced IL-2 responses correlated with the specific IgE (r = 0.62, P < 0.01) and proliferation (r = 0.51, P < 0.02) and S-IgE level (r = 0.71, P < 0. 002). Mannan-induced IL-4 and IFN-gamma productions also correlated (r = 0.43, P < 0.05). CONCLUSIONS: C. albicans mannan induced elevated IL-2 and IFN-gamma responses in AD patients. The correlations of the cytokine responses with mannan-induced IgE and proliferation responses suggest that C. albicans mannan induced TH1 type cytokine responses are involved in AD.  相似文献   
56.
57.

Background

Heroin is a synthetic opioid with an extensive illicit market leading to large numbers of people becoming addicted. Heroin users often present to community treatment services requesting detoxification and in the UK various agents are used to control symptoms of withdrawal. Dissatisfaction with methadone detoxification [8] has lead to the use of clonidine, lofexidine, buprenorphine and dihydrocodeine; however, there remains limited evaluative research. In Leeds, a city of 700,000 people in the North of England, dihydrocodeine is the detoxification agent of choice. Sublingual buprenorphine, however, is being introduced. The comparative value of these two drugs for helping people successfully and comfortably withdraw from heroin has never been compared in a randomised trial. Additionally, there is a paucity of research evaluating interventions among drug users in the primary care setting. This study seeks to address this by randomising drug users presenting in primary care to receive either dihydrocodeine or buprenorphine.

Methods/design

The Leeds Evaluation of Efficacy of Detoxification Study (LEEDS) project is a pragmatic randomised trial which will compare the open use of buprenorphine with dihydrocodeine for illicit opiate detoxification, in the UK primary care setting. The LEEDS project will involve consenting adults and will be run in specialist general practice surgeries throughout Leeds. The primary outcome will be the results of a urine opiate screening at the end of the detoxification regimen. Adverse effects and limited data to three and six months will be acquired.
  相似文献   
58.
目的:研究父母的母语为非英语的婴儿比父母的母语为英语的婴儿是否更不易接受推荐的预防性医疗行为。研究设计:笔者对1999年1月1日至2000年9月30日期间在华盛顿州出生的所有38793例参加医疗救助的1岁婴儿进行回顾性组群研究。主要因素为自己报告的父母的母语。笔者使用多参数回  相似文献   
59.
Recent studies of trisomy 21 have shown that altered levels of recombination are associated with maternal non-disjunction occurring at both meiosis I (MI) and meiosis II (MII). To comprehend better the association of recombination with nondisjunction, an understanding of the pattern of meiotic exchange, i.e. the exchange of genetic material at the four-strand stage during prophase, is required. We examined this underlying exchange pattern to determine if specific meiotic configurations are associated with a higher risk of non-disjunction than others. We examined the crossover frequencies of chromosome 21 for three populations: (i) normal female meiotic events; (ii) meiotic events leading to MI non-disjunction; and (iii) those leading to MII non-disjunction. From these crossover frequencies, we estimated the array of meiotic tetrads that produced the observed crossovers. Using this approach, we found that nearly one-half of MI errors were estimated to be achiasmate. The majority of the remaining MI bivalents had exchanges that clustered at the telomere. In contrast, exchanges occurring among MII cases clustered at the pericentromeric region of the chromosome. Unlike the single exchange distributions, double exchanges from the non-disjoined populations seemed to approximate the distribution in the normal population. These data suggest that the location of certain exchanges makes a tetrad susceptible to non- disjunction. Specifically, this susceptibility is associated with the distance between the centromere and closest exchange. This result challenges the widely held concept that events occurring at MII are largely independent of events occurring at MI, and suggests that all non-disjunction events may be initiated during MI and simply resolved at either of the two meiotic stages.   相似文献   
60.
Background: Metastatic uveal melanoma has a poor prognosis andlimited therapeutic options. Proteoglycans are involved in tumorcell invasion and metastatic behavior. The mAbB5 stains a chondroitinsulphate proteoglycan (CSPG) on cutaneous melanoma cells. Here,we compare the B5-staining of CSPG in primaries and metastasesof uveal melanoma. Material and methods: Immunohistopathological staining was performedin 15 cutaneous and 39 uveal melanoma samples. A score for intracellularand surface staining was established. B5 staining was comparedin primaries and metastases of uveal melanoma using Student'st-test. Results: Eight of 11 (73%) uveal melanoma metastases were positivefor B5-staining whereas only 5 of 28 (18%) primary uveal melanomasamples were B5-positive (P < 0.001). Nine of 15 cutaneousmelanoma samples (60%) were B5-positive without significantdifference between primary and metastatic lesions. Surface stainingwas found both on uveal melanoma metastases and cutaneous melanomas. Conclusions: CSPG was expressed significantly more often inmetastases than in primaries of uveal melanoma. It potentiallymay be one factor associated with metastatic spread. Furtherstudies are needed to determine its use as prognostic factor.The mAbB5 may also be a promising tool for immunotherapy dueto its strong staining of CSPG on the surface of cutaneous andmetastatic uveal melanoma cells. Key words: uveal melanoma, ocular melanoma, chondroitin sulphate proteoglycan, immunotherapy, immunohistochemistry  相似文献   
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