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101.
102.
Gene probe analysis of the MEN 2A locus on chromosome 10 hasbeen undertaken using the markers TB10.163, RBP 3 and TB14.34in a large kindred with familial medullary thyroid carcinomas,with or without phaeochromocytomas or primary hyperparathyroidism.A maximum LOD score of 2.97 gave strong evidence of close linkagewith zero recombination. For 12 members of the family so far not known to be affectedby any form of the disease the estimated risk of carrying thegene has been considerably decreased in all but one, whose riskhas been greatly increased.  相似文献   
103.
Capsular contracture is one of the major complications of augmentation mammaplasty. A review of 638 augmented breasts in 319 consecutive patients who underwent primary augmentation, with an average follow-up of 17.2 months and without a single case of capsular contracture of any degree to date, is presented, along with a discussion of the surgical technique and complications, and an analysis of measures used to prevent capsular contraction. Each patient received a pair of smooth saline-filled implants (Mentor, USA) placed in the submuscular space through an inframammary incision. In all operated breasts, many of the known measures commonly used for capsular contracture prevention were implemented. As well, a dependent drain was used as the final hemostatic step to prevent blood accumulation in the pocket. Leaving a dependent drain in the dissected pocket overnight, as one of the sequence of measures aimed at eliminating blood accumulation, is believed to be a contributing factor in capsular contracture prevention.  相似文献   
104.
 Besides 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), [4-(methylnitrosamino)-1-(3-pyridyl)but-1-yl]-β-O-d-glucosiduronic acid (NNAL-Glu) is another important metabolite of the tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) which has been detected in the urine of tobacco users and non-smokers heavily exposed to sidestream cigarette smoke. In order to evaluate the toxicological significance of NNAL-Glu formation and excretion, the metabolism of [5-3H]-NNAL-Glu was studied in rats. Five male F344 rats were administered 3.7 mg/kg [5-3H]-NNAL-Glu by i.v. injection and the metabolites in urine analysed by HPLC. More than 90% of the radioactivity was excreted in urine within the first 24 h. Unchanged NNAL-Glu accounted for 81.2±3.1% of the total radioactivity; the remaining part of the dose appears to be deconjugated resulting in the urinary excretion of NNAL (3.6±1.7%) and its α-hydroxylation (11.5±2.2%) and N-oxidation (3.6±1.6%) products. The presence of α-hydroxylation products of NNAL-Glu in urine suggests that this NNK metabolite may be activated in vivo to carcinogenic intermediates. Received: 25 April 1994 / Accepted: 29 June 1994  相似文献   
105.
106.
BACKGROUND: Chlamydia pneumoniae is known to cause acute respiratory infection and more recently it has been studied as a pathogen causing inflammatory changes in chronic diseases such as atherosclerosis. This study addresses the antichlamydial effect of levofloxacin and its role in modulation of a proinflammatory cytokine IL-6 production by uninfected and infected HEp-2 cells. METHODS: HEp-2 cell monolayers were infected with previously prepared and frozen aliquots of C.pneumoniae [1 x 10(3) inclusion-forming units (IFU)/ml] by centrifugation for 30 min and incubation at 37 degrees C for 1 h. Infected monolayers were treated with levofloxacin (3 or 8 microg/ml) immediately after infection (0 h) or 24 h after infection. Monolayers were examined daily for 96 h after infection by counting inclusions with fluorescently labeled antichlamydial monoclonal antibody. Aliquots of disrupted monolayers were titrated to determine the numbers of viable C. pneumoniae IFU/ml. IL-6 concentrations in cell supernatants were determined by ELISA assays. RESULTS: Infected HEp-2 cells produced IL-6. Noninfected HEp-2 cells demonstrated modulation of IL-6 production by levofloxacin. No viable C. Pneumoniae were detected in infected HEp-2 cells when the monolayer was treated with levofloxacin immediately after infection (0 h). In contrast, when cells were treated 24 h after infection, a gradual decline in the number of viable C. pneumoniae occurred; by 96 h into the assay >or=98% of C. pneumoniae were killed. IL-6 concentrations were similar in the supernatants of levofloxacin-treated and nontreated HEp-2 cells. CONCLUSIONS: (1). Levofloxacin is effective in eliminating C. pneumoniae from infected HEp-2 cells; (2). although levofloxacin modulates the production of IL-6 in untreated HEp-2 cells, no evidence for such modulation was observed in HEp-2 cells infected with C. pneumoniae. (3). Presence of viable C. pneumoniae may not be necessary for IL-6 production by infected and treated HEp-2 cells.  相似文献   
107.
This study evaluates the effects of cytokines, used singly and in combination, on the microbicidal activity of human monocyte-derived macrophages (MDM) against intracellular Candida albicans in the presence and absence of fluconazole. In the absence of fluconazole, the addition of tumor necrosis factor alpha (TNF-alpha), interleukin-1beta (IL-1beta), gamma interferon (IFN-gamma), or IL-4 had no effect on the growth of C. albicans. In contrast, the addition of granulocyte-macrophage colony-stimulating factor (GM-CSF) resulted in decreased growth (P < 0.05), while the addition of IL-10 resulted in increased growth (P < 0.01). In the presence of fluconazole, only the addition of IFN-gamma resulted in an increase in the growth of C. albicans. In the presence or absence of fluconazole, all cytokine combinations except IFN-gamma plus GM-CSF caused significant decreases in growth (P < 0.01). IL-10 and IL-4 did not influence the activity of TNF-alpha or IL-1beta. In the absence or presence of C. albicans the addition of fluconazole, all of the cytokines studied, and combinations of fluconazole and selected cytokines caused increases in nitric oxide (NO) production (P < 0.01). Similar observations were made for superoxide (O(2)(-)) only in the presence of C. albicans. The greatest concentrations of NO and O(2)(-) were produced when C. albicans alone was present in the assays. Our results demonstrate that in the presence of low concentrations of fluconazole (0.1 times the MIC), selected cytokines and their combinations significantly increase the microbicidal activity of MDM against intracellular C. albicans.  相似文献   
108.
A BamHI 3.7-kilobase (kb) fragment detected by an HLA-DQ beta-chain complementary DNA (cDNA) probe and negatively associated with insulin-dependent diabetes mellitus (IDDM) was cloned and sequenced to localize the polymorphism to BamHI sites in intervening sequences of an HLA-DQ beta-chain gene. A probe of the first intervening sequence (IVS 1) showed the BamHI 3.7-kb fragment in 6 of 17 HLA-DR3/4 controls but in 0 of 13 DR-identical IDDM patients. All IDDM patients (13 of 13) had BamHI fragments of 12 and 4 kb, detected in 9 of 17 controls (P less than 0.02). The simple restriction fragment length polymorphism pattern of the IVS 1 probe was exploited by comparing 113 IDDM patients with 177 healthy controls to show increased prevalences in IDDM of the 12-kb (P less than 0.0001) and 4-kb (P less than 0.0001) fragments. In IDDM patients younger than 20 yr at onset, 98% were 12- and/or 4-kb positive, compared with 63% of controls (P less than 0.0001), giving a relative risk of 91.8 for individuals with both fragments. The 12-kb fragment was linked to HLA-DR4, and the 4-kb fragment to HLA-DR3. Both serologic markers were split and a non-DR3/non-DR4 IDDM patient was 4-kb positive. HLA-DQ seems therefore closer, than HLA-DR, to an IDDM susceptibility gene.  相似文献   
109.

Background

Plasma levels of angiopoietin-2 (ANGPT2) and angiopoietin-like 4 protein (ANGPTL4) reflect different pathophysiological aspects of cardiovascular disease. We evaluated their association with outcome in a hospitalized Norwegian patient cohort (n = 871) with suspected acute coronary syndrome (ACS) and validated our results in a similar Argentinean cohort (n = 982).

Methods

A cox regression model, adjusting for traditional cardiovascular risk factors, was fitted for ANGPT2 and ANGPTL4, respectively, with all-cause mortality and cardiac death within 24 months and all-cause mortality within 60 months as the dependent variables.

Results

At 24 months follow-up, 138 (15.8%) of the Norwegian and 119 (12.1%) of the Argentinian cohort had died, of which 86 and 66 deaths, respectively, were classified as cardiac. At 60 months, a total of 259 (29.7%) and 173 (17.6%) patients, respectively, had died. ANGPT2 was independently associated with all-cause mortality in both cohorts at 24 months [hazard ratio (HR) 1.27 (95% confidence interval (CI), 1.08–1.50) for Norway, and HR 1.57 (95% CI, 1.27–1.95) for Argentina], with similar results at 60 months [HR 1.19 (95% CI, 1.05–1.35) (Norway), and HR 1.56 (95% CI, 1.30–1.88) (Argentina)], and was also significantly associated with cardiac death [HR 1.51 (95% CI, 1.14–2.00)], in the Argentinean population. ANGPTL4 was significantly associated with all-cause mortality in the Argentinean cohort at 24 months [HR 1.39 (95% CI, 1.15–1.68)] and at 60 months [HR 1.43 (95% CI, 1.23–1.67)], enforcing trends in the Norwegian population.

Conclusions

ANGPT2 and ANGPTL4 were significantly associated with outcome in similar ACS patient cohorts recruited on two continents.

Clinical Trial Registration

ClinicalTrials.gov Identifier: NCT00521976. ClinicalTrials.gov Identifier: NCT01377402.
  相似文献   
110.
To elucidate the causes of the diminished incretin effect in type 2 diabetes mellitus we investigated the secretion of the incretin hormones, glucagon-like peptide-1 and glucose- dependent insulinotropic polypeptide and measured nonesterified fatty acids, and plasma concentrations of insulin, C peptide, pancreatic polypeptide, and glucose during a 4-h mixed meal test in 54 heterogeneous type 2 diabetic patients, 33 matched control subjects with normal glucose tolerance, and 15 unmatched subjects with impaired glucose tolerance. The glucagon-like peptide-1 response in terms of area under the curve from 0-240 min after the start of the meal was significantly decreased in the patients (2482 +/- 145 compared with 3101 +/- 198 pmol/liter.240 min; P = 0.024). In addition, the area under the curve for glucose-dependent insulinotropic polypeptide was slightly decreased. In a multiple regression analysis, a model with diabetes, body mass index, male sex, insulin area under the curve (negative influence), glucose-dependent insulinotropic polypeptide area under the curve (negative influence), and glucagon area under the curve (positive influence) explained 42% of the variability of the glucagon-like peptide-1 response. The impaired glucose tolerance subjects were hyperinsulinemic and generally showed the same abnormalities as the diabetic patients, but to a lesser degree. We conclude that the meal-related glucagon-like peptide-1 response in type 2 diabetes is decreased, which may contribute to the decreased incretin effect in type 2 diabetes.  相似文献   
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