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71.
A precolumn derivatization method was optimized for rapid and specific analysis of total urinary hydroxyproline by HPLC. After an overnight hydrolysis, urine samples dried and reconstituted with the internal standard cysteic acid (in sodium hydrogen carbonate, pH 9.3) were derivatized with N,N-diethyl-2,4-dinitro-5-fluoroaniline (FDNDEA) at 100 degrees C for 20 min. The DNDEA-hydroxyproline adduct was separated on an Ultrasphere ODS column with a mobile phase of acetate buffer (containing triethylamine, 6 mL/L, pH 4.3) and acetonitrile (80/20, by vol), and was detected at 360 nm. A single run took 18 min with a hydroxyproline retention time of 7.3 min. The assay showed a linear response to hydroxyproline concentrations from 5 to 100 mg/L with a detection limit of 0.8 ng injected, corresponding to 2 mg/L in urine. Mean (SD) analytical recovery was 94.2 (13)% and 104 (9)% at 10 and 50 mg/L, respectively. Within-run and between-run CVs (n = 10) were 3.74% and 4.33%, respectively, for 25 mg/L. Results for samples (n = 50) analyzed by HPLC (y) vs ion-exchange chromatography with postcolumn ninhydrin reaction (x) correlated well: y = 0.98x + 1.02 (r = 0.985, Sxy = 3.13). In another comparison, involving 173 samples, a colorimetric procedure (Hypronosticon, x) gave slightly higher values than the HPLC method (y): y = 0.83x + 2.21 (r = 0.937, Sxy = 4.6).  相似文献   
72.
73.
Beta-2 microglobulin in patients on peritoneal dialysis and hemodialysis   总被引:1,自引:0,他引:1  
Serum beta 2 microglobulin (beta 2 mu) levels were determined in 62 patients on chronic dialysis, divided according to the type of dialysis--cuprophane hemodialysis, chronic ambulatory peritoneal dialysis (CAPD), or CAPD started after 76 +/- 47 months on cuprophane hemodialysis--and to residual urine output greater than 400 mL/day or less than 10 mL/day. In addition, for patients on CAPD, peritoneal excretion, peritoneal clearance, and urinary excretion of the protein were determined. In anuric patients serum beta 2 mu levels were significantly higher in HD than in CAPD. In patients with residual urine output, serum concentrations of the microprotein were similar in HD and in CAPD. Significant differences were observed in beta 2 mu serum levels and peritoneal clearances in patients switched to CAPD from hemodialysis as compared to those starting with CAPD. Peritoneal clearances of the microprotein was slightly and non-significantly greater in patients with urine output than in anuric patients.  相似文献   
74.
Fractalkine (FKN, CX3CL1) is a membrane-bound CX3C chemokine induced by primary proinflammatory signals in vascular endothelial cells (ECs). Here we examined the role of FKN in polarized Th1 or Th2 responses. Proinflammatory signals, including LPS, IL-1, TNF, and CD40 ligand, induced FKN, as did IFN-gamma, which had synergistic activity with TNF. IL-4 and IL-13 did not stimulate the expression of FKN and markedly reduced induction by TNF and IFN-gamma. TNF alone or combined with IFN-gamma also induced release of soluble FKN, which was inhibited by IL-4 and IL-13. In light of this differential regulation of FKN by the master cytokines that control polarized responses, we analyzed the interaction of FKN with natural killer (NK) cells and polarized T-cell populations. NK cells expressed high levels of the FKN receptor CX3CR1 and responded to FKN. CX3CR1 was preferentially expressed in Th1 compared with Th2 cells. Th1 but not Th2 cells responded to FKN. By immunohistochemistry, FKN was expressed on ECs in psoriasis, a Th1-dominated skin disorder, but not in Th2-driven atopic dermatitis. Similarly, ECs in Mycobacterium tuberculosis granulomatous lymphadenitis, but not those in reactive lymph node hyperplasia or in Castelman's disease, showed immunoreactive FKN. These results indicate that regulated expression of FKN in ECs participates in an amplification circuit of polarized type I responses.  相似文献   
75.
Aging and everyday memory: the beneficial effect of memory training   总被引:5,自引:0,他引:5  
The authors investigated elderly people's ability to benefit from specific memory training. Empirical evidence of cognitive aging shows a deterioration in working memory ability but also suggests that elderly people maintain the ability to acquire new information and strategies. The aim of the present study was to investigate the effects of two different mnemonic strategies (Loci mnemonic vs. Strategic training) in young and older adults and to evaluate the ability of the older groups to improve performance. Participants received extensive practice in the use of a specific strategy. Three groups of participants (20 adult, 20 younger elderly, and 20 older elderly) were tested in the laboratory, as well as in ecological conditions using a battery of cognitive tests. Questionnaires were also administrated to explore cognitive, metacognitive and emotive motivational aspects of working memory performance. The results show the efficacy of both trainings in improving performances in different tasks, particularly the ecological. The elderly benefit from strategies as much as younger people; nevertheless, the memory performances of the latter are higher. Differences between the two trainings are found only in the task evaluating ability to re-use learnt strategies in other unfamiliar situations. Improvement in performance was more pronounced for the strategic training.  相似文献   
76.
BACKGROUND: Chronic obstructive pulmonary disease (COPD) severity is usually graded upon the FEV(1) reduction and FEV(1) has been considered the most important mortality predictor with age in COPD. Recent studies suggest other factors as more powerfully related to mortality than FEV(1) in COPD patients. AIM: To assess the impact of inspiratory capacity (IC) on mortality and morbidity in COPD patients during a 5-year follow-up period. METHODS: We recruited 222 patients with mild-to-moderate COPD from January 1995 to December 2001 with an average follow-up period of 60 months (range 30-114 months). Among different respiratory parameters measured in stable conditions FEV(1), FEV(1)/FVC%, IC and PaO(2), PaCO(2) and BMI were chosen and their relationships with all-cause and respiratory mortality and with morbidity were assessed. RESULTS: All these variables were associated with mortality at the univariate analysis. However, in a multivariate regression analysis (Cox proportional hazards model) for all-cause mortality age (year), IC (%pred.) and PaO(2) (mmHg) remained the only significant, independent predictors (HR=1.056, 95%CI: 1.023-1.091; HR=0.981, 95%CI: 0.965-0.998; HR=0.948, 95%CI: 0.919-0.979, respectively). According to the same analysis, IC (%pred.) and PaO(2) (mmHg) were significant independent predictors for respiratory mortality (HR=0.967, 95%CI: 0.938-0.997; HR=0.919, 95%CI: 0.873-0.969) together with FEV(1)/FVC% and BMI (kg/m(2)) (HR=0.967, 95%CI: 0.933-1.022; HR=0.891, 95%CI: 0.807-0.985, respectively). IC (%pred.), FEV(1)/FVC%, and PaO(2) (mmHg) were also significantly related to morbidity, as independent predictors of hospital admissions because of exacerbations (OR=0.980, 95%CI: 0.974-0.992; OR=0.943, 95%CI: 0.922-0.987; OR=0.971, 95%CI: 0.954-0.996, respectively). CONCLUSION: IC (%pred.) is a powerful functional predictor of all-cause and respiratory mortality and of exacerbation-related hospital admissions in COPD patients.  相似文献   
77.
The creative arts can be used to support stakeholders of mental health services to communicate and share their lived experience. Digital storytelling is one method that has been used to capture people's lived experience. In this scoping review, we were interested in mapping how digital storytelling has been used in mental health, and to identify gaps in the literature. Nine databases were searched to identify peer reviewed literature published between January 2000 and August 2015; 15 articles were included in the review. The articles were categorized across four broad areas: educational interventions, learning skills, learning about other people's lived experience, and learning about personal lived experience. We identify that while digital storytelling has potential as a participatory process to promote mutual understanding of and empathy towards lived experiences in mental health, there is a dearth of research in this area. More research is needed on the use of digital storytelling in mental health to determine its effectiveness in progressing a recovery orientation in service provision that is built on solidarity and a social justice agenda.  相似文献   
78.
OBJECTIVES: To compare different mef(A) elements of Streptococcus pyogenes for a possible chimeric genetic nature, i.e. a transposon inserted into a prophage. METHODS: Eleven S. pyogenes isolates with efflux-mediated erythromycin resistance were used. The isolates were typed using several genotypic approaches. Gene detection was performed by PCR using specific primer pairs. The mef(A) elements of the test strains were induced with mitomycin C and phage DNA was extracted. Induction was monitored by PCR using primers targeting mef(A). RESULTS: Six tetracycline-susceptible isolates had PCR evidence of all of the eight open reading frames (ORFs) of the Tn1207.1 element; their mef(A) element was consistent with the Tn1207.3 element in four isolates and with the 58.8 kb chimeric element in two. Five tetracycline-resistant isolates had no PCR evidence of orf1 and orf2 and showed variable patterns as to orf3, orf7, and orf8. Three ORFs placed along the conserved region downstream of Tn1207.1 in the 58.8 kb mef(A) chimeric element were detected in the six tetracycline-susceptible, but not in the five tetracycline-resistant isolates. Induction assays with mitomycin C demonstrated that the mef(A) elements of all strains tested were present in culture supernatants in a DNAse-resistant form, such as a phage capsid. CONCLUSIONS: All recognized mef(A) elements of S. pyogenes appear to be prophage-associated. Whereas the two elements detected in tetracycline-susceptible isolates (Tn1207.3 and the 58.8 kb one) were apparently inserted into the same prophage, the tet(O)-mef(A) element was inserted into a different prophage. Phage transfer is likely to play a critical role in the dissemination of erythromycin resistance in S. pyogenes populations.  相似文献   
79.
Chronic liver disease is known to be associated with several vascular alterations including portal hypertension and hepato-pulmonary insufficiency. We report a case of esophageal vascular lesions resembling spider naevi in a patient with nonalcoholic cirrhosis who underwent an upper gastrointestinal (GI) endoscopy. We observed the presence of multiple white round elevations, 5–6 mm in size, with radiating thin-walled vessels, in the middle and distal esophagus. The histological examination documented the presence of multiple dilated blood vessels in the mucosal layer of the esophagus, with striking thickening of the endothelium wall. There was no evidence of esophagogastric varices, but only of a moderate congestive antral gastropathy. To our knowledge, these endoscopic esophageal findings have not yet been described in cirrhosis.  相似文献   
80.
Fetal loss in animals and humans is frequently associated with inflammatory conditions. D6 is a promiscuous chemokine receptor with decoy function, expressed in lymphatic endothelium, that recognizes and targets to degradation most inflammatory CC chemokines. Here, we report that D6 is expressed in placenta on invading extravillous trophoblasts and on the apical side of syncytiotrophoblast cells, at the very interface between maternal blood and fetus. Exposure of D6-/- pregnant mice to LPS or antiphospholipid autoantibodies results in higher levels of inflammatory CC chemokines and increased leukocyte infiltrate in placenta, causing an increased rate of fetal loss, which is prevented by blocking inflammatory chemokines. Thus, the promiscuous decoy receptor for inflammatory CC chemokines D6 plays a nonredundant role in the protection against fetal loss caused by systemic inflammation and antiphospholipid antibodies.  相似文献   
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