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11.
PURPOSE: Interleukin (IL)-1alpha and IL-6 levels in the cornea are greatly elevated during the early stages after an alkali burn in mice. The authors investigated the effect of synthetic inhibitor of matrix metalloproteinase (SIMP) on the expression of inflammatory cytokines in alkali-burned murine corneas and evaluated the clinical appearance of the eyes. METHODS: After 0.5N NaOH-alkali burns to 400 corneas of ICR mice, 200 received 400 microg/ml of SIMP topically 4 times a day while 200 corneas were similarly treated with vehicle only. At days 4, 7 and 14 after injury, each cornea was assigned a clinical score for corneal opacity, corneal epithelial defect, hyphema and cataract. Extracts of injured corneas in each group were then assayed for cytokine production using ELISA systems for IL-1alpha, IL-1beta, IL-6 and tumor necrosis factor-alpha (TNF-alpha). RESULTS: The levels of IL-1alpha, IL-1beta and IL-6 were significantly lower in the SIMP-treated group than in the vehicle-treated group 7 days after the burn. However, levels of these cytokines were similar in the SIMP and non-SIMP groups at days 4 and 14. Levels of TNF-alpha did not differ between both groups at any postinjury time. In the SIMP-treated corneas, there was less opacification and hyphema formation and epithelial regeneration was faster. CONCLUSIONS: Topical application of SIMP in alkali-burned murine corneas reduced the expression of IL-1alpha, IL-1beta, and IL-6 and lessened the severity of the injury.  相似文献   
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13.
The prevalence of Brugada's electrocardiographic (ECG) pattern in 7,022 male adolescents in the seventh grade was determined, and the same subjects were reexamined 3 years later, while in tenth grade. Two subjects (0.03%) and 7 subjects (0.10%) showed Brugada's ECG pattern by the conventional criterion (J point or ST-segment >/=0.1 mV in leads V(1) to V(3)), and no subjects (0%) and 2 subjects (0.03%) fulfilled the recent criterion (J point or ST-segment >/=0.2 mV) in the seventh and tenth grades, respectively, indicating that Brugada's ECG pattern begins to appear during junior high school and increases until late adulthood.  相似文献   
14.
OBJECTIVE: Insulin-like growth factor-I (IGF-I) deficiency may be involved in cognitive deficits seen with aging and in neurodegenerative diseases such as Alzheimer's disease (AD). This study was aimed at investigating whether non-responder to donepezil could be predicted using decreased serum levels of IGF-I in AD patients. DESIGN: This study involved 106 elderly subjects: 50 patients with AD and 56 age-matched controls without dementia. In patients with AD, donepezil was given orally 3 mg/day for 4 weeks and 5 mg/day for another 12 weeks. AD patients were divided into responders and non-responders based on the changes in mini-mental state examination (MMSE) scores before and 16 weeks after treatment with donepezil. Serum levels of IGF-I and atherogenic biomarkers were determined. RESULTS: Before treatment with donepezil, there was a significant positive correlation between serum IGF-I levels and the MMSE scores in all subjects. Serum IGF-I levels and the MMSE scores were significantly lower in AD patients than in non-demented controls and were the lowest in non-responders to donepezil. Atherogenic biomarkers (LDL cholesterol, triglycerides, lipoprotein(a), lipid peroxide, apolipoprotein E, and glucose levels) did not differ significantly among these groups. On multiple logistic regression, non-responders to donepezil showed decreased serum IGF-I levels <110 ng/ml and MMSE scores <15 points before treatment. CONCLUSIONS: These findings suggest that decreased levels of serum IGF-I combined with MMSE scores before treatment could predict non-responders to donepezil among AD patients, which may be a simple and practical method for selecting patients expected to show a response to treatment.  相似文献   
15.
Serum uric acid (UA) levels reflect circulating xanthine oxidase activity and oxidative stress production. Hyperuricemia has been identified in patients who have congestive heart failure and is a marker of poor prognosis in such patients. We investigated the relation between serum UA levels and Killip's classification suggestive of the severity of heart failure and whether hyperuricemia influences mortality of patients who have acute myocardial infarction (AMI). Using the Japanese Acute Coronary Syndrome Study database, we evaluated 1,124 consecutive patients who were hospitalized within 48 hours of onset of symptoms of AMI from January to December 2002. There was a close relation between serum UA concentration and Killip's classification. Patients who developed short-term adverse events had high UA concentrations. Serum UA levels, Killip's class, age, and peak creatine phosphokinase level were significant predictors of long-term mortality. The hazard ratio for patients in the highest quartile of UA was 3.7 compared with those in the lowest quartile for death after AMI after adjustment for independent factors that were related to mortality. The combination of the best UA cutoff (447 micromol/L) for predicting survival based on receiver-operating characteristics analysis and Killip's class significantly predicted the prognosis of acute and long-term AMI-related complications. In conclusion, our results suggest that hyperuricemia after AMI is associated with the development of heart failure. Serum UA level is a suitable marker for predicting AMI-related future adverse events, and the combination of Killip's class and serum UA level after AMI is a good predictor of mortality in patients who have AMI.  相似文献   
16.
Although advancement of succeeding atrial activation by a ventricular extrastimulus (VES) on His refractoriness during supraventricular tachycardia (SVT) has been used as evidence of an accessory pathway (AP), the sensitivity of this method is suboptimal. This study was designed to compare the His-His (H-H) and atrial-atrial (A-A) intervals of the first entrained cycle during ventricular overdrive pacing (VOD) for the diagnosis of AP, in comparison to the conventional VES method. In 55 patients with SVT, a VES was elicited on His refractoriness during SVT. VOD was subsequently performed at cycle lengths 30 to 40 ms shorter than SVT cycle lengths. When the A-A interval became equal to the pacing cycle length after some beats of VOD, the cycle was considered the first entrained cycle and the H-H interval preceding the A-A interval was measured. VES advanced the next atrial activation in 16 patients (52%) with an AP, but in no patient without an AP. The H-H interval of the first entrained cycle was longer than the pacing cycle length by > or =15 ms in all patients with an AP, but was equal to the pacing cycle length in all patients without an AP. The criterion of H-H greater than A-A by > or =15 ms for the first entrained cycle provided higher diagnostic yield for AP compared with the VES method(100% vs 52%, p <0.001). In conclusion, this new criterion reliably diagnoses the presence of an AP in patients with SVT, with higher sensitivity compared with the VES method.  相似文献   
17.
The relation between functional response to brief nitroglycerin infusions and extent of myocardial damage was studied sequentially in closed-chest dogs with acute occlusion of the left anterior descending coronary artery. Two-dimensional echocardiography was used to derive segmental left ventricular (LV) function (systolic fractional area change and systolic wall thickening), and this function was compared with the extent of necrosis measured 5 hours after occlusion in equivalent segments of corresponding pathologic slabs. Two-dimensional echocardiographic study before the dogs were killed indicated that remote nonnecrotic segments always responded to nitroglycerin by significant augmentation of segmental LV function. Segments in which necrosis was less than 40% showed a significant nitroglycerin-induced potentiation in segmental LV function. In contrast, segments in which necrosis was greater than 60% had no potentiation with nitroglycerin. In those segments in which eventual necrosis was 60 to 80%, significant nitroglycerin-induced augmentation in segmental LV function was observed only before and 30 minutes after the coronary occlusion. When the degree of necrosis was greater than 80%, no significant potentiation of segmental LV function was observed even as early as 30 minutes after occlusion. Thus, the degree of nitroglycerin-induced potentiation of segmental cardiac function is closely associated with the extent of myocardial necrosis in the particular ventricular segment. Two-dimensional echocardiography coupled with a nitroglycerin potentiation test might be useful for assessment of the viability of ischemic myocardium.  相似文献   
18.
Few data have been published on the reproducibility of baseline subtracted peak intensity obtained from intravenous intermittent triggered myocardial contrast echocardiography. We investigated the reproducibility of the peak intensity measured from intravenous intermittent triggered myocardial contrast echocardiography in 10 young healthy males. The contrast echocardiography was obtained using the second harmonic mode with an intravenous bolus injection of Levovist (first study). The same myocardial contrast echocardiography was repeated after the first study (second study). The myocardial opacification and peak intensity in the 12 segments of the apical 4 and 2 chamber views were assessed visually and quantitatively. The differences in the peak intensity between the initial and repeated measurements in the first study (intraobserver reproducibility) and between the initial measurements in the first and second studies (interinjection reproducibility) were assessed using the Bland and Altman method. The degree of opacification was good or intermediate in 207/228 (91%) of the segments. The agreement of myocardial opacification between the first and second studies was 87/114 (76%). However, significantly higher peak intensity was obtained in apical septal (8200 +/- 6300 au2) and mid septal (8500 +/- 6000 au2) segments in the 4 chamber view and in the mid inferior (12400 +/- 9300 au2) and apical inferior (10700 +/- 6300 au2) segments in the 2 chamber view compared with other segments. The mean differences of the peak intensities according to the Bland and Altman analysis was -1600 +/- 5000 au2 in the intraobserver reproducibility study, and -1100 +/- 5300 au2 in the interinjection reproducibility study. Thus, the measurement error was determined to range from 8400 au2 to 9500 au2 in both studies. We conclude that the peak intensity obtained from intravenous intermittent triggered myocardial contrast echocardiography using Levovist varies significantly among segments in the left ventricular myocardium. Large intraobserver and interinjection variability exists in the measurement of peak intensity, suggesting that the reproducibility of this technique is limited for quantitative assessment of myocardial perfusion.  相似文献   
19.
BACKGROUND: The association between myocardial infarction (MI) and the R353Q polymorphism of the Factor VII (FVII) gene, which reportedly influences FVII concentrations, activated Factor VII (FVIIa), or FVII antigen (FVIIag), remains controversial. METHODS AND RESULTS: The present case - control study in 127 Japanese men with their first MI at or before 45 years of age and 150 matched healthy controls was designed to clarify this association in premature MI. R353Q polymorphism was determined by polymerase chain reaction, and plasma concentrations of FVIIa and FVIIag were assayed. The distribution of the RR, RQ, and QQ genotypes with respect to R353Q polymorphism was 117, 10, and 0 in the patients, and 131, 17, and 2 in the controls. The Q allele was negatively associated with premature MI (odds ratio =0.41, p=0.038). The plasma concentration of FVIIa was slightly higher in patients (55.1+/-40.9 U/L) than in controls (44.8+/-20.2 U/L), but not significantly (p=0.078); the plasma concentration of FVIIag did not differ between patients (88.7+/-15.7%) and controls (87.0+/-9.0%) (p=0.557). Plasma FVIIa concentrations were influenced by R353Q polymorphism (p<0.001). CONCLUSIONS: The Q allele may be protective against premature MI.  相似文献   
20.
BACKGROUND: A rapid 30-minute assay of circulating smooth-muscle myosin heavy-chain protein has been developed as a biochemical diagnostic tool for aortic dissection. OBJECTIVE: To determine the sensitivity and specificity of this assay. DESIGN: Cross-sectional study. SETTING: 8 major cardiovascular centers in Japan. PATIENTS: 95 patients with acute aortic dissection, 48 patients with acute myocardial infarction, and 131 healthy volunteers. MEASUREMENTS: Levels of circulating smooth-muscle myosin heavy-chain protein. RESULTS: Patients with acute aortic dissection who presented within 3 hours after onset had elevated levels of circulating smooth-muscle myosin heavy-chain protein. In these patients, the assay had a sensitivity of 90.9%, a specificity of 98% compared with healthy volunteers, and a specificity of 83% compared with patients who had acute myocardial infarction; the clinical decision limit was 2.5 microgram/L. All patients with proximal lesions had elevated levels of smooth-muscle myosin heavy-chain protein, and only patients with distal lesions had decreased levels (<2.5 microgram/L). CONCLUSIONS: Levels of smooth-muscle myosin heavy-chain protein can be used to diagnose aortic dissection soon after symptom onset. The assay had the greatest diagnostic value in patients with proximal lesions.  相似文献   
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