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41.

Much concern was directed towards the crucial role of recombinant tissue plasminogen activator (rt-PA) in improving neuroplasticity in patients with acute ischemic stroke. The aim of the work to investigate the effect of treating patients with acute ischemic stroke with rt-PA, on the level of brain derived neurotrophic factor (BDNF) as a marker of neuroplasticity. This study was conducted on 47 patients presenting with acute ischemic stroke (during the first 4.5 h from stroke onset); 26 patients of them eligible for receiving rt-PA (patient group) and 21 patients having contraindications for treatment with rt-PA (control group). Neurological, radiological and laboratory assessment (including BDNF serum level) were done for both groups at stroke onset (before receiving rt-PA) and at day 7. There was a statistically significant increase in BDNF serum level from day 1 to day 7 in rt-PA treated patients in comparison to control group (P-value? 0.001). Serum level of BDNF is significantly higher at the onset of stroke in female patients and non-smokers than males or smokers (P-value?=?0.011, 0.01 respectively). There was no effect of either age, body mass index, hypertension, diabetes, drug abuse, past or family history of stroke, valvular heart diseases, atrial fibrillation, cardiomyopathy, ejection fraction, carotid atherosclerotic changes, lipid profile or uric acid, on BDNF serum level measured at the onset of stroke. Treatment of patients with acute ischemic stroke with rt-PA causes significant improvement in neuroplasticity through increasing BDNF serum level.

  相似文献   
42.
Depletion of total antioxidant capacity in type 2 diabetes   总被引:4,自引:0,他引:4  
The purpose of the study was to examine the relationship between antioxidant depletion, glycemic control, and development of chronic complications in a controlled population of type 2 diabetic patients. Fifty age-matched type 2 diabetic patients receiving sulfonylureas but not insulin treatment were screened and assigned to two groups based on the presence or absence of proteinuria. A third group of normal subjects without diabetes were also enrolled in the study. All subjects in the three groups were Egyptians who were matched for body weight, and the two diabetic groups were also age-matched. Plasma glucose and fructosamine levels were higher in the two groups of diabetic patients versus the control group, but lipid peroxide levels were higher only in the patients with proteinuria. Compared with the control group, the total antioxidant capacity was depleted in the two diabetic groups, but the depletion was more severe in patients with proteinuria. Thus, the mean Trolox equivalent antioxidant capacity (TEAC) of the control group was 2.7+/-0.45, versus 1.7+/-0.5 (P < .001) in the patients without proteinuria. Furthermore, the TEAC measured in patients with proteinuria, who also had more diabetic complications, was lower (1.4+/-0.5, P < .001) than the TEAC in patients without urinary protein. In conclusion, a depletion of the total antioxidant capacity is associated with a higher incidence of diabetic complications.  相似文献   
43.
Increased susceptibility to mucosal damage is a prominent feature of portal hypertensive gastropathy. Since the portal hypertensive gastric mucosa has extensive microvascular changes, we postulated that the increased sensitivity to mucosal damage could have an ischemic basis. We measured distribution of gastric serosal and mucosal oxygenation in a group of portal hypertensive and sham-operated rats, and then studied the effects of intragastric aspirin. In the basal state, gastric mucosa of portal hypertensive rats had significantly reduced oxygenation compared to controls (24±5 vs 45±7 mm Hg PO 2,P < 0.02), while serosal oxygenation was similar between the two groups. Intragastric aspirin produced significantly greater mucosal damage to portal hypertensive rats and mucosal oxygenation was almost one third that of sham-operated controls. Systemic arterial pressures and oxygenation were similar between the two groups. We conclude that there is impairment of gastric mucosal oxygenation and increased mucosal damage by aspirin in portal hypertensive rats compared with sham-operated controls. These results support our hypothesis that the increased sensitivity of the portal hypertensive mucosa to damage is a consequence of impaired mucosal oxygenation.This study was supported by the Veterans Administration Research Service.This work was presented, in part, at the Plenary Session of the American Association for the Study of Liver Diseases, May 1988, New Orleans, Louisiana.  相似文献   
44.
Circulating leptin, insulin, insulin-like growth factor-I (IGF-I), cortisol, and albumin concentrations and the growth hormone (GH) response to provocation were measured in 30 children with severe protein-energy malnutrition (PEM), 20 with marasmus and 10 with kwashiorkor, as well as 10 age-matched normal children (body mass index [BMI] >50th and <90th percentile for age and sex) and 10 prepubertal obese children (BMI >95th percentile for age and sex). Patients with PEM had a significantly lower BMI, midarm circumference (MAC), and skinfold thickness (SFT) compared with the age-matched control group. Basal cortisol and GH concentrations were significantly higher in the malnourished groups versus controls. Leptin and IGF-I were significantly lower in the marasmic and kwashiorkor groups versus normal children. Fasting insulin levels were significantly decreased in the kwashiorkor group compared with marasmic and normal children. The BMI correlated significantly with leptin (r = .77, P < .001), basal insulin (r = .61, P < .001), and IGF-I (r = .77, P < .001) and negatively with basal GH (r = -.52, P < .001). These findings suggest that during prolonged nutritional deprivation, the decreased energy intake, diminished subcutaneous fat mass, and declining insulin (and possibly IGF-I) concentration suppress leptin production. In support of this view, serum leptin levels were positively correlated with triceps, scapular, and abdominal SFT (r = .763, .75, and .744, respectively, P < .0001) in all of the children. Moreover, basal insulin and circulating IGF-I were correlated significantly with leptin concentrations (r = .47 and .62, respectively, P < .001). Basal levels of cortisol and GH were significantly elevated in the 2 groups with severe PEM. It is suggested that low leptin levels can stimulate the hypothalamic-pituitary-adrenal (HPA) axis and possibly the hypothalamic-pituitary-GH axis to maintain the high cortisol and GH levels necessary for effective lipolysis to ensure a fuel (fatty acids) supply for the metabolism of brain and peripheral tissue during nutritional deprivation. In summary, during prolonged PEM, the decreased synthesis of IGF-I and the low level of insulin and/or its diminished effect due to an insulin-resistant status in the presence of high circulating GH and cortisol levels ensure substrate diversion away from growth toward metabolic homeostasis. Leptin appears to be an important signal in the process of metabolic/endocrine adaptation to prolonged nutritional deprivation.  相似文献   
45.
The clinical value of the estimation of systolic pulmonary artery pressure, based on Doppler assessment of peak tricuspid regurgitant velocity using transoesophageal echocardiography, is unclear. We studied 109 patients to evaluate the feasibility of obtaining adequate Doppler recordings, and compared Doppler estimates with values measured using a pulmonary artery catheter in a subset of 33 patients. Tricuspid regurgitation was evaluated at the mid‐oesophageal level at 0–120° using Doppler echocardiography. A Doppler signal was defined as adequate if there was a ≤ 20° alignment and a full envelope. Doppler estimates of systolic pulmonary artery pressure within 10 mmHg and 15% of the value recorded with the pulmonary artery catheter were considered to be in sufficient agreement. Adequate Doppler signals were obtained in 64/109 (59%) patients before and 54/103 (52%) after surgery. Doppler estimates by transoesophageal echocardiography were within 10 mmHg and 15% of values recorded with the pulmonary artery catheter in 28/33 (75%) patients and 22/31 (55%) patients, respectively. In 7 (21%) patients, the echocardiographic Doppler measurement exceeded the measured systolic pulmonary artery pressure by more than 30%. Our study indicates that estimation of the systolic pulmonary artery pressure using transoesophageal Doppler echocardiography is not a reliable and clinically useful method in anaesthetised patients undergoing mechanical ventilation.  相似文献   
46.
While belatacept has shown favorable short‐ and midterm results in kidney transplant recipients, only projections exist regarding its potential impact on long‐term outcome. Therefore, we performed a retrospective case‐match analysis of the 14 belatacept patients originally enrolled in the phase II multicenter trial at our center. Fifty six cyclosporine (CyA)‐treated patients were matched according to age at transplantation, first/retransplant, and donor type. Ten years after kidney transplantation, kidney function remained superior in belatacept‐treated patients compared with the CyA control group. Moreover, none of the belatacept‐treated patients had donor‐specific antibodies ≥10 years post‐transplantation compared with 38.5% of tested CyA‐treated subject (0/10 vs. 5/13; P = 0.045). Notably, however, patient and graft survival was virtually identical in both groups (71.4% vs. 71.3%; P = 0.976). In the present single‐center study population, patients treated with belatacept demonstrated a patient and graft survival at 10 years post‐transplant which was comparable to that of similarly selected CNI‐treated patients. Larger studies with sufficient statistical power are necessary to definitively determine long‐term graft survival with belatacept.  相似文献   
47.

Objective

Increasing evidence doubts the benign nature of metabolically healthy obesity (MHO). An investigation of the association of MHO and other obesity phenotypes with electrocardiographic left ventricular hypertrophy (ECG-LVH), a risk factor for cardiovascular disease (CVD), can give insight into the pathophysiological basis for increased risk of CVD linked to these phenotypes.

Methods

This analysis included 3997 participants (58.7?±?13.6?years; 51.8% women) without CVD from the NHANES-III. Metabolic syndrome was defined according to the Adult Treatment Panel III. Obesity was defined as body mass index ≥30?kg/m2. Multivariable logistic regression was used to examine the cross-sectional association between 4 obesity phenotypes (metabolically healthy non-obese (MHNO) (reference), metabolically unhealthy non-obese (MUNO), MHO and metabolically unhealthy obese (MUO) with Cornell voltage ECG-LVH.

Results

There was an incremental increase in the prevalence of ECG-LVH across obesity phenotypes with the highest prevalence in the MUO followed by MHO, MUNO and then MHNO (ECG-LVH?=?6.45%, 5%, 4.71%, and 1.69%, respectively, trend p-value?<?0.001). Also, there was incremental increase in the strength of associations with ECG-LVH across obesity phenotypes with higher odds of ECG-LVH in the MUO (OR (95% CI): 4.12 (2.30–7.39) followed by MUNO (OR (95% CI): 2.62 (1.45–4.73) then MHO (OR (95% CI): 2.45 (1.11–5.43) compared to MHNO. The MHO association with ECG-LVH was stronger in men than women (OR (95% CI): 5.55 (1.49–20.70) vs. 1.94 (0.71–5.24) respectively; interaction p-value?=?0.04).

Conclusions

Obesity phenotypes including MHO are associated with ECG-LVH, thus further questioning the concept of benign obesity.  相似文献   
48.
ObjectivesThis study aimed to validate a dedicated software for quantitative videodensitometric angiographic assessment of mitral regurgitation (QMR).BackgroundQuantitative videodensitometric aortography of aortic regurgitation using the time-density principle is a well-documented technique, but the angiographic assessment of mitral regurgitation (MR) remains at best semi-quantitative and operator dependent.MethodsFourteen sheep underwent surgical mitral valve replacement using 2 different prostheses. Pre-sacrifice left ventriculograms were used to assess MR fraction (MRF) using QMR and MR volume (MRV). In an independent core lab, the CAAS QMR 0.1 was used for QMR analysis. In vitro MRF and MRV were assessed in a mock circulation at a comparable cardiac output to the in vivo one by thermodilution. The correlations and agreements of in vitro and in vivo MRF, MRV, and interobserver reproducibility for QMR analysis were assessed using the averaged cardiac cycles (CCs).ResultsIn vivo derived MRF by QMR strongly correlated with in vitro derived MRF, regardless of the number of the CCs analyzed (best correlation: 3 CCs y = 0.446 + 0.994x; R = 0.784; p =0.002). The mean absolute difference between in vitro derived MRF and in vivo derived MRF from 3 CCs was 0.01 ± 4.2% on Bland-Altman analysis. In vitro MRV and in vivo MRV from 3 CCs were very strongly correlated (y = 0.196 + 1.255x; R = 0.839; p < 0.001). The mean absolute difference between in vitro MRV and in vivo MRV from 3 CCs was –1.4 ± 1.9 ml. There were very strong correlations of in vivo MRF between 2 independent analysts, regardless of the number of the CCs.ConclusionsIn vivo MRF using the novel software is feasible, accurate, and highly reproducible. These promising results have led us to initiate the first human feasibility study comprising patients undergoing percutaneous mitral valve edge-to-edge repair.  相似文献   
49.

Background

Patch electrocardiographic (ECG) monitors permit extended noninvasive ambulatory monitoring. To guide use of these devices, information is needed about their performance. We sought to determine in a large general population sample the acceptability of patch ECG monitors, the yield of arrhythmia detection, and the consistency of findings in participants monitored twice.

Methods

In the Multi-Ethnic Study of Atherosclerosis, 1122 participants completed one or two monitoring episodes using the Zio Patch XT, a single-channel ECG patch monitor capable of recording for 14?days. Recordings were analyzed for atrial fibrillation (AF), atrial flutter, atrioventricular block, pauses, and supraventricular and ventricular ectopy.

Results

The mean(SD) age at the time of monitoring was 75(8) years, 52% were men, and 15% had a prior history of clinically-recognized AF/flutter. The median monitoring duration was 13.8?days. Among 804 participants with no prior clinical history of AF/flutter and at least 12?days of monitoring on a single device, AF/flutter was detected in 32 (4.0%); in 38% of these, AF/flutter was first detected during days 3 through 12 of monitoring. In participants monitored twice, findings from the two devices showed excellent agreement for supraventricular and ventricular ectopic beats per hour, but only fair agreement for high-grade atrioventricular block and pauses of >3?s duration.

Conclusions

In a general population of older individuals, new diagnoses of AF/flutter were made in 4.0% of participants without a prior history. A single monitoring episode accurately estimated rates of supraventricular and ventricular ectopy.  相似文献   
50.
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