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101.
Mangaloglu L Cheung RC Van Iderstine SC Taghibiglou C Pontrelli L Adeli K 《Metabolism: clinical and experimental》2002,51(4):409-418
A novel animal model of insulin resistance, the fructose-fed Syrian golden hamster has been previously documented to exhibit considerable hepatic very-low-density lipoprotein (VLDL) overproduction concomitant with the development of whole body insulin resistance. Here, we investigated whether hepatic lipoprotein overproduction can be ameliorated by treatment with a hydroxymethyl glutaryl conenzyme A (HMG-CoA) reductase inhibitor, atorvastatin, using a series of ex vivo experiments. Hamsters were fed a fructose-enriched diet for 14 days to induce a state of insulin resistance, and then continued on a fructose-enriched diet supplemented with or without 40 mg/kg atorvastatin per day for 14 days. Fructose feeding in the first 2 weeks caused a significant increase in plasma total cholesterol and triglyceride levels. There was a significant decline in plasma triglyceride levels following supplementation with the inhibitor (50% to 59%; P <.05). Experiments with primary hepatocytes revealed a decreased VLDL-apolipoprotein B (apoB) production (37.4% +/- 10.4%; P <.05) in hamsters treated with atorvastatin. Interestingly, atorvastatin treatment partially attenuated (by 23%) the elevated hepatic level of microsomal triglyceride transfer protein (MTP) induced by fructose feeding. There was molecular evidence of improved hepatic insulin sensitivity with atorvastatin treatment based on assessment of the phosphorylation status of the insulin receptor and the expression of protein tyrosine phosphatase-1B. The improvement in insulin signaling was not mediated by a change in hepatic triglyceride accumulation as no significant difference was observed in liver triglyceride levels. Taken together, these data suggest that statins can ameliorate the VLDL-apoB overproduction state observed in a fructose-fed, insulin-resistant hamster model, and may potentially contribute to an enhanced hepatic insulin sensitivity. 相似文献
102.
Adenosine bronchial provocation with computerized wheeze detection in young infants with prolonged cough: correlation with long-term follow-up 总被引:1,自引:0,他引:1
BACKGROUND: Chronic cough in babies is often associated with bronchial hyperreactivity (BHR). The objective documentation of BHR in babies is difficult, and acoustic methods have been described (provocative concentration of a substance causing wheeze) for conducting bronchial provocation tests (BPTs). We conducted a study to evaluate automatic computerized wheeze detection (CWD) in determining BHR in young infants with prolonged cough, and its correlation with the subsequent development of wheezing. METHODS: Infants aged < 24 months with prolonged cough (ie, > 2 months) underwent acoustic BPTs with the response determined by CWD and auscultation by a physician. Telephone interviews with parents were conducted after 1 month and yearly for the next 3 years. RESULTS: A total of 28 infants who were 4 to 24 months old with prolonged cough were included in the study. Twenty of these infants (71.4%) had BHR as determined by a positive acoustic BPT result. In 11 of these 20 tests, the CWD occurred earlier, and in 9 tests it occurred at the same step as auscultation by a physician. Rhonchi or whistles often preceded wheezes. Seventeen of the 20 patients with BHR completed 3 years of follow-up. Of these, 14 had recurrent episodes of wheezing and shortness of breath, and 3 were well. Six of the eight adenosine-negative patients completed 3 years of follow-up and had no symptoms of BHR. CONCLUSIONS: Acoustic BPT is a technically feasible test for the detection of BHR in young infants. CWD provides an earlier detection of wheeze than stethoscope auscultation. In our group of infants, a positive acoustic BPT result had high correlation with symptoms compatible with BHR over the next 3 years. 相似文献
103.
The association of differing measures of overweight and obesity with prevalent atherosclerosis: the Dallas Heart Study. 总被引:1,自引:0,他引:1
Raphael See Shuaib M Abdullah Darren K McGuire Amit Khera Mahesh J Patel Jason B Lindsey Scott M Grundy James A de Lemos 《Journal of the American College of Cardiology》2007,50(8):752-759
OBJECTIVES: This study sought to evaluate the associations between different measures of obesity and prevalent atherosclerosis in a large population-based cohort. BACKGROUND: Although obesity is associated with cardiovascular mortality, it is unclear whether this relationship is mediated by increased atherosclerotic burden. METHODS: Using data from the Dallas Heart Study, we assessed the association between gender-specific obesity measures (i.e., body mass index [BMI]; waist circumference [WC]; waist-to-hip ratio [WHR]) and prevalent atherosclerosis defined as coronary artery calcium (CAC) score >10 Agatston units measured by electron-beam computed tomography and detectable aortic plaque measured by magnetic resonance imaging. RESULTS: In univariable analyses (n = 2,744), CAC prevalence was significantly greater only in the fifth versus first quintile of BMI, whereas it increased stepwise across quintiles of WC and WHR (p trend <0.001 for each). After multivariable adjustment for standard risk factors, prevalent CAC was more frequent in the fifth versus first quintile of WHR (odds ratio 1.91, 95% confidence interval 1.30 to 2.80), whereas no independent positive association was observed for BMI or WC. Similar results were observed for aortic plaque in both univariable and multivariable-adjusted analyses. The c-statistic for discrimination of prevalent CAC was greater for WHR compared with BMI and WC in women and men (p < 0.001 vs. BMI; p < 0.01 vs. WC). CONCLUSIONS: We discovered that WHR was independently associated with prevalent atherosclerosis and provided better discrimination than either BMI or WC. The associations between obesity measurements and atherosclerosis mirror those observed between obesity and cardiovascular mortality, suggesting that obesity contributes to cardiovascular mortality via increased atherosclerotic burden. 相似文献
104.
再发骨质疏松性椎体压缩骨折保守治疗患者出院后生存质量 总被引:1,自引:0,他引:1
目的:对比初次和再发骨质疏松性椎体压缩骨折(osteoporotic vertebral compression fractures,OVCFs)患者保
守治疗的生存质量,了解再次骨折对此类患者生存质量各方面的影响。方法:回顾性观察治疗OVCFs后出现再骨折
的患者30名(再骨折组)和同时期行保守治疗OVCFs后未发生再骨折的基本条件相似的患者30例(对照组),比较两组出
院后3个月时SF-36简明健康健康状况调查表的调查结果。结果:再骨折组治疗后的8个维度均不同程度较对照组变差
(均P<0.01)。结论:再骨折组患者的生存质量明显低于对照组,并且会进一步影响患者的心理预期、情绪和社会活动
的各个方面。 相似文献
105.
106.
107.
D M Knowles G A Chamulak M Subar J S Burke M Dugan J Wernz C Slywotzky G Pelicci R Dalla-Favera B Raphael 《Annals of internal medicine》1988,108(5):744-753
We identified 105 patients with lymphoid neoplasia associated with the acquired immunodeficiency syndrome (AIDS) at the New York University Medical Center from 1981 through 1986: 89 had non-Hodgkin lymphoma; 13, Hodgkin disease; and 3, chronic lymphocytic leukemia. Immunophenotypic and antigen receptor gene rearrangement analysis showed the B-cell origin of all non-Hodgkin lymphomas studied and the clonal suppressor-cytotoxic T-cell subset origin of the chronic lymphocytic leukemias. We classified 69% of the non-Hodgkin lymphomas as high grade (small, noncleaved and large cell, immunoblastic-plasmacytoid) and 31% as intermediate grade (diffuse large cell). Each histopathologic category was correlated with distinct clinical features, including a statistically significant difference in median survival. Patients with Hodgkin disease had an atypical, aggressive clinical course, whereas patients with T-cell chronic lymphocytic leukemia had an indolent clinical course. These studies show the clinical, morphologic, and immunophenotypic spectrum of AIDS-associated lymphoid neoplasia, that the natural history of Hodgkin disease is altered in patients with AIDS, and support the Centers For Disease Control's recent revision in diagnostic criteria for AIDS to include intermediate-grade diffuse, aggressive non-Hodgkin lymphomas occurring in patients seropositive for human immunodeficiency virus. 相似文献
108.
Host defense and inflammatory gene polymorphisms are associated with outcomes after HLA-identical sibling bone marrow transplantation 总被引:3,自引:4,他引:3 下载免费PDF全文
Rocha V Franco RF Porcher R Bittencourt H Silva WA Latouche A Devergie A Esperou H Ribaud P Socie G Zago MA Gluckman E 《Blood》2002,100(12):3908-3918
We made the hypothesis that donor and recipient gene polymorphisms that drive the host response to microorganisms could be associated with infections after bone marrow transplantation (BMT). HLA-identical BMT was performed for patients with acute (n = 39) or chronic leukemia (n = 68). Genotyping was performed in 107 D/R DNA pairs for gene polymorphisms of cytokines (tumor necrosis factor-alpha [TNF-alpha] and TNF-beta, interleukin-1 receptor antagonist [IL-1Ra], IL-6, and IL-10), adhesion molecules (CD31 and CD54), Fcgammareceptors (FcgammaRIIa, IIIa, IIIb), mannose-binding lectin (MBL), and myeloperoxidase (MPO). First infection (overall) and first episodes of bacterial, viral, or invasive fungal infection were studied retrospectively for 180 days after BMT. Univariate and multivariate analyses, using death as a competing event, were performed to study risk factors. In multivariate analysis, first overall infections were increased in patients with the FcgammaRIIa R-131 genotype (hazard ratio [HR] = 1.92; P =.04), and severe bacterial infections were increased when the MPO donor genotype was AG or AA (HR = 2.16; P =.03). Viral and invasive fungal infections were not influenced by any genetic factor studied. Interestingly, we also found that (1) time to neutrophil recovery was shorter when donors were FcgammaRIIIb HNA-1a/HNA-1b (HR = 1.77; P =.002); (2) donor IL-1Ra (absence of IL-1RN*2) increased the risk for acute graft-versus-host disease (GVHD) (II-IV) (HR = 2.17; P =.017); and (3) recipient IL-10 (GG) and IL-1Ra genotypes increased the risk for chronic GVHD (P =.03 and P =.03, respectively). Finally, 180-day transplantation-related mortality rates were increased when donors were FcgammaRIIIb HNA-1a/HNA-1a or HNA-1b/HNA-1b (HR = 2.57; P =.05) and donor MPO genotype was AA (HR = 5.14; P =.004). In conclusion, donor and recipient gene polymorphisms are informative genetic risk factors for selecting donor/recipient pairs and could help in the understanding of mechanisms involved in host defenses of BM transplant recipients. 相似文献
109.
Feller-Kopman D Lukanich JM Shapira G Kolodny U Schori B Edenfield H Temelkuran B Ernst A Schindel Y Fink Y Fox J Bueno R 《Chest》2008,133(4):892-896
BACKGROUND: Thermal ablation is one of the most commonly used modalities to treat central airway obstruction. Both laser and argon plasma coagulation (APC) have been reported to cause gas emboli and cardiac arrest. We sought to determine whether bronchoscopic ablation therapy can result in systemic gas emboli, correlate their presence with the rate of gas flow, and establish whether a zero-flow (ZF) modality would result in the significant reduction or elimination of emboli. METHODS: CO(2) laser delivered through a photonic bandgap fiber (PBF) and APC were applied in the trachea and mainstem bronchi of six anesthetized sheep at varying dosages and gas flow rates. Direct epicardial echocardiography was used to obtain a four-chamber view and detect gas emboli. RESULTS: The presence of gas flow accompanying APC and the CO(2) laser with forward flow correlated significantly with the appearance of gas bubbles in the atria. A definite dose response was observed between the gas flow rate and the number of bubbles seen. When the CO(2) laser was delivered through a PBF with ZF to the trachea or bronchi, no bubbles were observed. CONCLUSION: Bronchoscopic thermal ablation therapy using gas flow is associated with gas emboli in a dose-dependent fashion. The use of the flexible PBF with ZF is not associated with the development of gas emboli. Further study is required to determine whether a clinically safe threshold of gas emboli exists, and the relationships among the pathologic depth of tissue destruction, gas flow, pulse duration, and the development of gas emboli. 相似文献
110.
Regina Böll Katrin Romanek Sabrina Schmoll Raphael Stich Armin Ott Jochen Stenzel 《Clinical toxicology (Philadelphia, Pa.)》2018,56(7):664-666
Objective: To independently validate the predictive value of the intensive care requirement score (IRS) in unselected poisoned patients.Design: Retrospective chart review.Patients and methods: Five hundred and seventeen out of 585 admissions for acute intoxications could be analyzed. Eleven were excluded for a condition already requiring intensive care unit (ICU) support at admission (e.g., preclinical intubation). A further 57 admissions were excluded due to missing data. The IRS was calculated using a point-scoring system including age, Glasgow Coma Scale, heart rate, type of intoxication, and preexisting conditions. It was then compared to a composite endpoint indicating an ICU requirement (death in hospital, vasopressors, need for ventilation). The endpoint and the point-scoring system were identical to the original publication of the score.Results and conclusion: Twenty-three out of 517 patients had a complicated clinical course as defined by meeting the endpoint definition. Twenty-one out of 23 complicated courses had a positive IRS (defined as greater or equal 6 points), as compared to 255/494 patients with an uncomplicated clinical course (p?.001, Fisher’s exact test). One patient (with a positive IRS) died. The negative predictive value of the IRS was 0.99 (95% CI: 0.97–1), the sensitivity was 0.91 and the specificity 0.48. In conclusion, the IRS is significantly linked to outcome. While a negative IRS virtually excludes the need for ICU care, a positive IRS has a positive predictive value too low to be used for risk stratification. The IRS could also be applied to unselected admissions of poisoned patients. 相似文献