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71.
Hurst JR  Hagan G  Wedzicha JA 《Chest》2007,132(4):1409; author reply 1409-1409; author reply 1410
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BACKGROUND: We sought to describe the prevalence of metabolic abnormalities and of metabolic syndrome (MS) and its relationship to target-organ damage in children with primary hypertension (PH). METHODS: Patients included 113 children with untreated PH at a mean age of 14.6 years (range, 5 to 18 years). The control group consisted of 134 healthy children at a mean age of 13.5 years (range, 5 to 20 years). We performed a cross-sectional assessment of anthropometric and biochemical cardiovascular risk factors, homeostatic metabolic assessment (HOMA-IR), the insulin sensitivity index (ISI[0,120]), and adiponectin. RESULTS: Metabolic syndrome, as defined by classic criteria, was present in 4 of 134 (3%) of controls versus 23 of 113 (20.4%) patients (P=.0001), but when PH was not taken as a criterion of MS, MS was diagnosed in 6.2% of patients (no significance). Left-ventricular hypertrophy (LVH) was found in 46 of 113 patients (40.7%), and severe LVH was found in 14 of 113 patients (12.5%). Patients with LVH had a greater body mass index, greater waist-to-hip-ratio, and greater number of parameters of metabolic syndrome (overall P<.05). Carotid (cIMT) and femoral superficial artery intima-media thicknesses correlated positively with HOMA-IR and negatively with ISI[0.120] and serum adiponectin (P<.05). The main predictor for cIMT was adiponectin (R2=0.178, beta=-0.466, P=.002). Left-ventricular hypertrophy was predicted (R2=0.332) by body mass index-standard deviation score (beta=0.551, P=.005) and HOMA-IR (beta=0.380, P=.04). CONCLUSIONS: Metabolic syndrome, as defined by classic criteria, was diagnosed in 20% of children with PH, but when PH was not a criterion, MS was present in 6.2% of patients. Irrespective of the definition of MS, the applied markers of MS and insulin resistance were the main predictors of target-organ damage.  相似文献   
74.
Bronchodilators, including long-acting beta(2)-adrenoceptor agonists and anticholinergic bronchodilators, are effective in the treatment of chronic obstructive pulmonary disease. Evidence suggests that the addition of a long-acting beta(2)-agonist to an inhaled corticosteroid is associated with a reduced rate of exacerbations compared with either treatment alone or placebo. However, it is not known whether a long-acting beta(2)-agonist/inhaled corticosteroid combination is more effective than an anticholinergic bronchodilator alone in reducing exacerbations. The Investigating New Standards for Prophylaxis In Reduction of Exacerbations (INSPIRE) trial will study salmeterol (a long-acting beta(2)-agonist) in combination with fluticasone propionate (an inhaled corticosteroid) compared with tiotropium bromide (an anticholinergic bronchodilator) in patients with moderate-to-severe chronic obstructive pulmonary disease. The INSPIRE study is a multicentre, randomised, double-blind, double dummy, parallel group study conducted over 104 weeks. This is the first study to use two parallel definitions of an exacerbation; an event-based exacerbation is defined as one that requires use of healthcare resources, including additional treatment and hospitalization, whereas a symptom-based exacerbation is defined as one that satisfies the 1987 Anthonisen criteria. It is also the first study to compare the long-term effects of salmeterol/fluticasone propionate with tiotropium bromide on the rate of event-based exacerbations. Endpoints include rate of exacerbations (primary endpoint), time to first exacerbation, and duration of exacerbations. Health outcomes will be assessed via the St George's Respiratory Questionnaire. If the innovative methodology of utilizing 2 definitions of exacerbation proves successful, it will set the benchmark for future studies in chronic obstructive pulmonary disease.  相似文献   
75.
Previous reports have shown that the human immunodeficiency virus (HIV) regulatory protein Tat has both pro-oxidant and pro-inflammatory properties, suggesting that Tat might contribute to the neurological complications of HIV. However, the intracellular mechanisms whereby Tat triggers free radical production and inflammation, and the relationship between Tat-induced free radicals and inflammatory reactions, are still subject to debate. The present study was undertaken to evaluate the specific effects of Tat on NADPH oxidase in microglia and macrophages, and to determine the specific role of NADPH oxidase in Tat-induced cytokine/chemokine release and neurotoxicity. Application of Tat to microglia or macrophages caused dose- and time-dependent increases in superoxide formation that were prevented by both pharmacologic NADPH oxidase inhibitors and by specific decoy peptides (gp91ds). Furthermore, inhibition of NADPH oxidase attenuated Tat-induced release of interleukin-6 (IL-6), tumor necrosis factor alpha (TNF), and monocyte chemoattractant protein 1 (MCP-1), and decreased microglial-mediated neurotoxicity. Finally, macrophages derived from NADPH oxidase-deficient mice displayed reduced superoxide production, released lower levels of cytokines/chemokines, and induced less neurotoxicity in response to Tat compared to wild-type macrophages. Together, these data describe a specific and biologically significant signaling component of the macrophage/microglial response to Tat, and suggest the neuropathology associated with HIV infection might originate in part with Tat-induced activation of NADPH oxidase.  相似文献   
76.
People vulnerable to depression are at increased risk of relapse if they live in highly critical family environments. To explore this link, we used neuroimaging methods to examine cortico-limbic responding to personal criticisms in healthy participants and participants with known vulnerability to major depression. Healthy controls and fully recovered participants with a past history of major depression were scanned while they heard praising, critical, and neutral comments from their own mothers. Prior to scanning, the formerly depressed and the control participants were indistinguishable with respect to self-reported positive, negative, or anxious mood. They also reported similar mood changes after being praised or criticized. However, formerly depressed participants responded to criticism with greater activation in the amygdala and less activation in the dorsolateral prefrontal cortex (DLPFC) and anterior cingulate cortex (ACC) than did controls. During praise and neutral commentary, amygdala activation was comparable in both groups, although lower levels of activation in the DLPFC and ACC still characterized formerly depressed participants. Vulnerability to depression may be associated with abnormalities in cortico-limbic activation that are independent of mood state and that remain even after full recovery. Criticism may be a risk factor for relapse because it activates the amygdala and perturbs the affective circuitry that underlies depression.  相似文献   
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Hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis and elevated cortisol (CORT) levels are characteristics of the pathophysiology of major depressive disorder.The aim of this study was to determine whether increased plasma CORT levels appear in patients with major depression and if effective antidepressant treatment by clomipramine (CLO) leads to regulation of CORT level. Plasma CORT levels were measured using high performance liquid chromatography (HPLC) methods in patients with major depression at time zero (before therapy) and after 3 h, 24 h, 4, 6 and 8 weeks of CLO administration. The study included 17 patients (12 women, 5 men; mean age 54.5 years, SD = 12.3) and 21 healthy comparison subjects. The patients had a mean score on the 21-item Hamilton Depression Rating Scale (HDRS) of 26.8 (range 22–35). Eight of the patients with major depression recruited for the study showed a 46% increase in CORT concentration compared to the established standard. In 13 patients treated with CLO, serum CLO levels reached a therapeutic range. In recovered depressed patients, antidepressant treatment significantly reduced HDRS scores from the 6th week of treatment. Adrop in plasma CORT levels in recovered depressed subjects occurred 0 to 6 weeks after CLO treatment (n = 5, p < 0.046). However, neither subject group exhibited any definitive markers of CORT secretion. In the population studied, patients had distinct profiles of HPA axis dysregulation. Finding a linear correlation between lower CORT secretion and therapeutic plasma CLO levels is the first aim of monitored therapy and may be important for understanding the pathophysiology of major depressive disorder.  相似文献   
79.
Cladribine (2-chlorodeoxyadenosine, 2-CdA) treatment-associated infections may shorten potentially long-term survival in hairy cell leukemia (HCL). In search of the optimal mode of 2-CdA administration, 132 patients with untreated HCL were randomized to receive either standard 5-day 2-CdA protocol or a novel schedule of 6 weekly 2-CdA infusions suggested to be less toxic. Analysis of treatment response confirmed similar complete remission rates, overall response rates, progression-free survival, and overall survival in both 2-CdA protocols. However, we did not observe lower toxicity in the weekly schedule. Of special interest, no significant differences were found in the rate of grade 3/4 infections (18% for daily and 26% for weekly protocol, difference –8.2%; 95% confidence interval [CI] –23.2% to 6.9%; P = .28) and the rate of septic deaths (3% for daily and 2% for weekly protocol, difference 1.4%; 95% CI –4.3% to 7.0%; P = .64). In conclusion, HCL treatment with weekly 2-CdA infusions is equally effective but no safer than the standard 5-day 2-CdA protocol.   相似文献   
80.
OBJECTIVE: Elastase is a key proteolytic enzyme released during polymorphonuclear leukocyte degranulation. There are abundant data of elastase involvement in the development of injury in experimental models of glomerulonephritis (GN), but scant direct evidence of its involvement in human primary GN. The aims of this study were to determine the immunolocalization of elastase deposits in kidney biopsy specimens from patients with primary idiopathic GN, to attempt to correlate the distribution and intensity of deposits with urinary elastase excretion, and to determine clinical markers of renal injury in several types of primary idiopathic GN. MATERIAL AND METHODS: The immunohistochemical localization and intensity of elastase deposits in kidney biopsies, the urinary excretion of leukocyte elastase, and proteinuria and serum creatinine levels were evaluated in 23 patients with primary GN and the associations between these factors were sought. RESULTS: Patients with crescentic proliferative GN had the highest intensity of elastase deposits. In this group of patients, elastase was present in the glomerular endothelium, as well as in the tubular epithelium and interstitium. Patients with a high intensity of elastase deposits within the glomerular endothelium and Bowman's capsule had significantly higher urinary excretion of elastase. Patients with interstitial, mesangial and perivascular elastase deposits had significantly higher serum creatinine than those without. Patients with elastase deposits in the glomerular endothelium and in the interstitium had insignificantly higher proteinuria than those without. CONCLUSION: Our data provide morphological evidence of leukocyte elastase involvement in renal injury occurring in the course of primary idiopathic GN, in particular in the proliferative types.  相似文献   
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