483 resultados para Weeks, Harrison
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PURPOSE: To compare mechanical and ethanol epithelial removal with respect to myofibroblast development and haze formation after photorefractive keratectomy (PRK). METHODS: Seventeen rabbits underwent mechanical or ethanol debridement, and the opposite eye of each rabbit served as an unwounded control. In both groups, the epithelium was removed with a spatula and discarded. A -9.00-diopter PRK was performed in each eye. The level of haze in each cornea at 4 weeks was graded at the slit-lamp microscope according to the Fantes scale. Myofibroblast generation was detected with immunocytochemistry for alpha-smooth muscle actin (alpha-SMA) and cells were quantitatively analyzed. RESULTS: No difference was noted between the two groups in alpha-SMA + myofibroblasts 4 weeks after surgery (43.6 +/- 2.0/400X field and 45.7 +/- 4.8/400X field in ethanol and mechanical groups, respectively) (P=.10). A slight difference was noted but did not reach statistical significance with regard to stromal haze between ethanol and mechanical groups (2.0 +/- 0.5 and 2.3 +/- 0.4, respectively, P=.063). The ethanol and mechanical groups were statistically different when compared to controls regarding stromal haze and alpha-SMA+ cells (P <.0001 for all comparisons). CONCLUSIONS:No difference was noted in clinical haze or myofibroblast generation between corneas that had PRK with mechanical,or ethanol epithelial debridement. [J Refract Surg., 2008;24:923-927.]
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BACKGROUND Spontaneously hypertensive rats (SHRs) show increased cardiac sympathetic activity, which could stimulate cardiomyocyte hypertrophy, cardiac damage, and apoptosis. Norepinephrine (NE)induced cardiac oxidative stress seems to be involved in SHR cardiac hypertrophy development. Because exercise training (ET) decreases sympathetic activation and oxidative stress, it may alter cardiac hypertrophy in SHR. The aim of this study was to determine, in vivo, whether ET alters cardiac sympathetic modulation on cardiovascular system and whether a correlation exists between cardiac oxidative stress and hypertrophy. METHODS Male SHRs (15-weeks old) were divided into sedentary hypertensive (SHR, n = 7) and exercise-trained hypertensive rats (SHR-T, n = 7). Moderate ET was performed on a treadmill (5 days/week, 60 min, 10 weeks). After ET, cardiopulmonary reflex responses were assessed by bolus injections of 5-HT. Autoregressive spectral estimation was performed for systolic arterial pressure (SAP) with oscillatory components quantified as low (LF: 0.2-0.75 Hz) and high (HF:0.75-4.0 Hz) frequency ranges. Cardiac NE concentration, lipid peroxidation, antioxidant enzymes activities, and total nitrates/nitrites were determined. RESULTS ET reduced mean arterial pressure, SAP variability (SAP var), LIF of SAP, and cardiac hypertrophy and increased cardiopulmonary reflex responses. Cardiac lipid peroxidation was decreased in trained SHRs and positively correlated with NE concentrations (r= 0.89, P < 0.01) and heart weight/body weight ratio (r= 0.72, P < 0.01), and inversely correlated with total nitrates/nitrites (r= -0.79, P < 0.01). Moreover, in trained SHR, cardiac total nitrates/nitrites were inversely correlated with NE concentrations (r= -0.82, P < 0.01). CONCLUSIONS ET attenuates cardiac sympathetic modulation and cardiac hypertrophy, which were associated with reduced oxidative stress and increased nitric oxide (NO) bioavailability. Am J Hypertens 2008;21:1138-1193 (C) 2008 American Journal of Hypertension, Ltd.
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Background: Patients with diabetes mellitus who undergo coronary stenting are at increased risk of restenosis. It is known that inflammation plays a crucial role in restenosis. Objective: We assessed the inflammatory response to elective coronary stent implantation (CSI) in stable diabetic and nondiabetic patients. Methods: C-reactive protein (CRP), soluble (s) P-selectin, and soluble intercellular adhesion molecule (sICAM)-1 plasma levels were determined in diabetic (n = 51) and nondiabetic (n = 56) patients before and 48 hours and 4 weeks after bare metal stenting (BMS). Results: Diabetic patients presented significantly higher inflammatory marker levels before and after CSI. Nonetheless, diabetic and nondiabetic patients had postintervention peak of markers attained within 48 hours. At baseline, diabetic and nondiabetic patients presented CRP levels of 5.0 +/- 20.1 (P <= 0.04) and 3.8 +/- 9.4 mu g/ml and, at 48 hours postintervention, 22.0 +/- 20.2 (P = 0.001; P = 0.002) and 12.6 +/- 11.3 (P <= 0.0001) mu g/ml. Regarding sP-selectin, diabetic and nondiabetic patients obtained levels of, at baseline, 182 +/- 118 (P <= 0.04) and 105 +/- 48 ng/ml and, at 48 hours, 455 +/- 290 (P = 0.001; P <= 0.01) and 215 +/- 120 (P <= 0.04) ng/ml. For diabetic and nondiabetic patients, sICAM-1 levels were, at baseline, 248 +/- 98 (P <= 0.04) and 199 +/- 94 ng/ml and, at 48 hours, 601 +/- 201 (P = 0.001; P <= 0.01) and 283 +/- 220 (P = 0.001) ng/ml. At 4 weeks, for all patients, markers returned to preprocedural levels: versus before PCI: *P = 0.001, P <= 0.0001; versus nondiabetic patients: #P <= 0.04, P = 0.002, UpsilonP <= 0.01. Conclusions: Diabetic and nondiabetic patients exhibited a temporal inflammatory response after an elective BMS. However, diabetic patients present higher preprocedural levels of CRP, sP-selectin, and sICAM-1 and reveal a further exacerbated inflammatory response after intervention. The differences in inflammatory response may have implications in restenosis within these two sets of patients.
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Objectives To report the feasibility of early fetal cystoscopy for the prenatal diagnosis and therapy of severe first-trimester megacystis. Methods Between January 2008 and February 2010, early fetal cystoscopy at 16 weeks of gestation was offered to 15 patients whose fetuses presented with severe first-trimester megacystis. All infants were followed up for 6-12 months after birth. Autopsy was always performed whenever fetal or neonatal deaths occurred. Results Seven patients decided to undergo fetal therapy, and eight elected to continue with expectant observation. One fetus died before early fetal cystoscopy was performed. Therefore, six fetuses underwent early fetal cystoscopy. Urethral atresia was diagnosed in three fetuses during fetal cystoscopy and confirmed at autopsy following termination of pregnancy at 19-20 weeks in all cases. Posterior urethral valves were diagnosed and successfully fulgurated by laser during early cystoscopy in three fetuses, two of which survived with normal renal and bladder function after birth; the remaining fetus had a postnatal diagnosis of megacystis-microcolon intestinal hypoperistalsis syndrome and died neonatally. In the expectantly managed group, no survivals were observed, even among cases with `isolated` posterior urethral valves. Conclusions Percutaneous early fetal cystoscopy is feasible for prenatal diagnosis and therapy of severe megacystis. Copyright (C) 2011 ISUOG. Published by John Wiley & Sons, Ltd.
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Background: Cadherins and integrins are important for maintenance of tissue integrity and in signal transduction during skin development. Distribution of these molecules in human skin development was investigated and associated with markers of differentiation, cytokeratins (CK) and involucrin (INV). Methods: Using immunohistochemistry expression of E- and P-cadherins, integrins beta-1 and -4, CK10, CK14 and INV was assessed in skin fragments of 10 human fetuses (gestational weeks ranged from 4 to 24, all weighing up to 500 g). Results: At initial phases of development, integrins beta-1 and -4 and E- and P-cadherins were present on epithelial cell membranes in all layers. CK14 and CK10 were expressed in all epithelial layers and INV weakly detected in the superficial layer. In more advanced stages, integrins were detected in all layers, but a marked polarized expression was seen in basal layer. E-cadherin was detected in all layers, but the cornified stratum and P-cadherin were observed in the lower layers. CK14 was expressed in basal layer, CK10 in suprabasal stratum and INV was observed in cornified layer. Conclusions: Cadherins and integrins are essential for skin development, being spatially and temporally regulated. Their expression is related with the expression of maturation markers of the epidermis.
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Chronic urticaria (daily or almost daily symptoms lasting for more than six weeks) is characterized by wheals and erythema, with or without itching. A few case reports have shown chronic autoimmune urticaria at the beginning of systemic lupus erythematosus (SLE), particularly in adults. However, the prevalence of this manifestation in a lupus paediatric population was not studied. During 27 consecutive years, 5419 patients were followed up at our University Hospital and 271 (5%) had juvenile SLE (American College of Rheumatology criteria). Two of them (0.7%) had chronic and painless autoimmune urticaria as the first manifestation of juvenile SLE, and were reported herein. One case was a five-year old female with continuous widespread urticaria (duration 120 days), antinuclear antibodies (ANA) 1:640 (dense fine speckled pattern) and elevated complement levels. The juvenile SLE diagnosis was established after one year. The other case was a 13-year old female who had chronic widespread urticaria (lasting 45 days), ANA 1:160 (fine speckled pattern) and normal complement levels. The juvenile SLE diagnosis was established after three years. In conclusion, chronic autoimmune urticaria is very rare and may be the first lupus manifestation, particularly associated with the presence of autoantibodies. This study reinforces the importance of a rigorous follow-up in children and adolescents suffering from autoimmune urticaria due to the possibility of connective tissue disorders, such as paediatric lupus. Lupus (2011) 20, 763-766.
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Background: Sustained beta-adrenoreceptor activation promotes cardiac hypertrophy and cellular injury. Aims: To evaluate the cardioprotective effect of exercise on damage induced by beta-adrenergic hyperactivity. Methods: Male Wistar rats were randomised into four groups (n=8 per group): sedentary non-treated control (C), sedentary treated with isoproterenol 0.3 mg/kg/day administered subcutaneously for 8 days (1), exercised non-treated (E) and exercised plus isoproterenol administered during the last eight days of exercise (IE). Exercised animals ran on a treadmill for 1 h daily 6 times a week for 13 weeks. Results: Isoproterenol caused increases in left ventricle (LV) wet and dry weight/body weight ratio, LV water content and cardiomyocyte transverse diameter. Additionally, isoproterenol induced severe cellular lesions, necrosis, and apoptosis, increased collagen content and reduced capillary and fibre fractional areas. Notably, all of these abnormalities were completely prevented by exercise. Conclusion: Our data have demonstrated that complete cardioprotection is possible through exercise training; by preventing p-adrenergic hyperactivity-induced cardiac hypertrophy and structural injury. (c) 2008 European Society of Cardiology. Published by Elsevier B.V. All rights reserved.
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Purpose. To build nomograms of fetal thyroid circumference (FTC), fetal thyroid area (FTA), and fetal thyroid transverse diameter (FTTD) throughout gestational age (GA). Method. Between January 2006 and July 2006, FTC, FTA, and FTTD were measured once in 196 normal fetuses examined at a GA of 22-35 weeks. Inclusion criteria were a healthy mother with normal maternal thyrotropin level during pregnancy, a singleton pregnancy with normal fetal morphology on sonography, and GA confirmed via first-trimester sonographic examination. Results. Mean FTC, FTA, and FTTD ranged from 3.21 cm, 0.58 cm(2), and 1.19 cm at 22 weeks to 5.11 cm, 1.69 cm(2), and 1.89 cm at 35 weeks, respectively. Linear regression analysis yielded the following formulas for FTC, FTA, and FTTD according to GA: FTC (cm) = 0.146 X GA (weeks); FTA (cm(2)) = -1.289 + 0.085 X GA (weeks); FTTD (cm) = 0.054 X GA (weeks). The following logarithmic formulas were obtained for the expected fetal thyroid measurements according to estimated fetal weight (FW): FTC (cm) = -4.791 + 1.265 X logN FW; FTA (cm(2)) = -1.676 + 0.455 X logN FW; and FTTD (cm) = 0.399 + 0.001 X logN FW. Conclusion. We describe new nomograms of fetal thyroid measurements throughout gestation that may be useful in case of thyroid dysfunction. (C) 2008 Wiley Periodicals, Inc.
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This article aims at investigating in vivo evaluation of lyophilization procedure on the biocompatibility of bovine pericardium treated with glutaraldehyde (GA). The bovine pericardium was fixed with 0.5% glutaraldehyde during 10 days and preserved in 4% formaldehyde (FA). Two groups of samples were prepared from treated membranes: Group 1, nonlyophilized samples and Group 2, lyophilized samples. Male Sprague-Dawley rats (4 weeks after birth) were anesthetized (pentobarbital sodium 25 mg/kg of body weight) and in each one were implanted subcutaneously in the dorsal region a sample from Group 1 and another from Group 2. These samples were explanted after 30 days for histological analysis. No intercurrences took place after the surgery. No differences (P > 0.05) in the calcification, granulomatous reaction, mononuclear infiltration, and granulation tissue development was observed between both groups. The implanted lyophilized samples presented a trend for a reduced inflammatory reaction. Lyophilization of the bovine pericardium does not seem to increase the above listed tissue reaction.
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Twenty-nine HCV-infected patients were treated with pegylated interferon alpha. Diagnosis was based on serum HCV RNA-PCR positive results and liver biopsy. All patients had elevated serum levels of alanine aminotransferase at the time of the study, but liver disease was compensated. Patients were evaluated at baseline treatment and after 4 and 12 weeks of antiviral treatment with the Medical Outcomes Study 36-item Short-Form Health Survey. The Mini-International Neuropsychiatric Interview was used to exclude previous or current psychiatric diagnoses. Both patients and psychiatrists were blind to the HCV RNA status, and serum HCV RNA test results only became available after the visit at week 12. After antiviral treatment, 16 patients (55.2%) were classified as nonresponders and 13 (44.8%) were classified as responders. When compared to nonresponders, responders had a greater improvement in the HRQOL scores for the mental health domain (P<.019). Differences in other domains were not significant. The present study confirms that active viral infection is one possible reason for the poor Health-Related Quality of Life in this population.
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Objective - We hypothesized that reactive oxygen species ( ROS) contribute to progression of aortic valve ( AV) calcification/ stenosis. Methods and Results - We investigated ROS production and effects of antioxidants tempol and lipoic acid ( LA) in calcification progression in rabbits given 0.5% cholesterol diet +10(4) IU/d Vit.D-2 for 12 weeks. Superoxide and H2O2 microfluorotopography and 3-nitrotyrosine immunoreactivity showed increased signals not only in macrophages but preferentially around calcifying foci, in cells expressing osteoblast/ osteoclast, but not macrophage markers. Such cells also showed increased expression of NAD(P) H oxidase subunits Nox2, p22phox, and protein disulfide isomerase. Nox4, but not Nox1 mRNA, was increased. Tempol augmented whereas LA decreased H2O2 signals. Importantly, AV calcification, assessed by echocardiography and histomorphometry, decreased 43% to 70% with LA, but increased with tempol (P <= 0.05). Tempol further enhanced apoptosis and Nox4 expression. In human sclerotic or stenotic AV, we found analogous increases in ROS production and NAD(P) H oxidase expression around calcifying foci. An in vitro vascular smooth muscle cell (VSMC) calcification model also exhibited increased, catalase-inhibitable, calcium deposit with tempol, but not with LA. Conclusions - Our data provide evidence that ROS, particularly hydrogen peroxide, potentiate AV calcification progression. However, tempol exhibited a paradoxical effect, exacerbating AV/vascular calcification, likely because of its induced increase in peroxide generation.
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Objective To investigate whether the cox-2 inhibitor celecoxib has antidepressant effects in bipolar disorder (BD) patients during depressive or mixed phases. Methods We studied 28 DSM-IV BD patients who were experiencing a depressive or mixed episode and were on a stable dose of a mood stabilizer or atypical antipsychotic medication. Subjects were randomized to receive 6 weeks of double-blind placebo or celecoxib (400 mg/day) treatment. Current mood stabilizer or antipsychotic medication remained at the same doses during the trial. Results Intention-to-treat analysis showed that the patients receiving celecoxib had lower Hamilton Depression Rating Scale (HamD) scores after 1 week of treatment compared to the patients receiving placebo, but this difference was not statistically significant (p=0.09). The improvement in the first week of treatment was statistically significant when the analysis included only the subjects who completed the full 6-week trial (p=0.03). The two groups did not differ significantly on depressive or manic symptoms from the second week until the end of the trial. Celecoxib was well tolerated with the exception of two subjects who dropped out of the study due to rash. Conclusions Our findings suggest that adjunctive treatment with celecoxib may produce a rapid-onset antidepressant effect in BD patients experiencing depressive or mixed episodes. Copyright (C) 2008 John Wiley & Sons, Ltd.
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Objectives (1) Study the effectiveness of intravariceal injection of n-butyl-2-cyanoacrylate to treat acute gastric variceal (GV) bleeding and (2) study the impact of the type of GV and hepatic function on endoscopic hemostasis and mortality outcomes. Methods Fourty-eight patients with acute GV bleeding underwent intravariceal injection of n-butyl-2-cyanoacrylate and were followed until death or study conclusion (12-52 months). Results Primary hemostasis (no re-bleeding within 48 h) was accomplished in 42 patients (87.5%). Appearance of the bleeding site at the time of initial endoscopy, grade of cirrhosis and location of GV were not significant predictors of immediate hemostasis. Early re-bleeding (48 h to 6 weeks) occurred in 20.5% of patients and late re-bleeding (beyond 6 weeks) in 20.5% of patients. While the Child-Pugh score was predictive of re-bleeding and mortality, the type of GV and stigmata at initial endoscopy were not significant predictors of re-bleeding and mortality. Over a mean follow-up of 18 months, mortality rates were 43.9% and bleeding was the commonest cause of death. Conclusion Endoscopic injection of n-butyl-2-cyanoacrylate is effective and safe for treating bleeding GV. Patients with poor hepatic function are at higher risk of re-bleeding and death after acute gastric variceal bleed.
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Recent studies have investigated whether low level laser therapy (LLLT) can optimize human muscle performance in physical exercise. This study tested the effect of LLLT on muscle performance in physical strength training in humans compared with strength training only. The study involved 36 men (20.8 +/- 2.2 years old), clinically healthy, with a beginner and/or moderate physical activity training pattern. The subjects were randomly distributed into three groups: TLG (training with LLLT), TG (training only) and CG (control). The training for TG and TLG subjects involved the leg-press exercise with a load equal to 80% of one repetition maximum (1RM) in the leg-press test over 12 consecutive weeks. The LLLT was applied to the quadriceps muscle of both lower limbs of the TLG subjects immediately after the end of each training session. Using an infrared laser device (808 nm) with six diodes of 60 mW each a total energy of 50.4 J of LLLT was administered over 140 s. Muscle strength was assessed using the 1RM leg-press test and the isokinetic dynamometer test. The muscle volume of the thigh of the dominant limb was assessed by thigh perimetry. The TLG subjects showed an increase of 55% in the 1RM leg-press test, which was significantly higher than the increases in the TG subjects (26%, P = 0.033) and in the CG subjects (0.27%, P < 0.001). The TLG was the only group to show an increase in muscle performance in the isokinetic dynamometry test compared with baseline. The increases in thigh perimeter in the TLG subjects and TG subjects were not significantly different (4.52% and 2.75%, respectively; P = 0.775). Strength training associated with LLLT can increase muscle performance compared with strength training only.
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We focused on the effect of mild hyperhomocysteinemia (HHcy) on the development of atherosclerosis, using apolipoprotein E-deficient (apoE(-/-)) and normal mice. Mice received diets enriched in methionine with low or high levels of folate, B(12) and B(6) (diets B and C, respectively), and diet only with low levels of folate, B(12) and B(6) (diets D), to induce mild HHcy. Normal mice fed on diets B, C and D presented mild HHcy, but they did not develop atherosclerotic lesions after 24 weeks of diet. In addition, increased endoplasmic reticulum stress was present in normal mice fed on diet B, compared to others groups. ApoE(-/-) mice fed on diet B for 20 weeks presented the greatest atherosclerotic lesion area at the aortic sinus than other groups. These results suggest that the methionine may have a toxic effect on endothelium, and the B-vitamins addition on diet may have a protective effect in the long term, despite the increase on homocysteine levels. Mild HHcy accelerated the development of atherosclerosis in apoE(-/-) mice, and supplementation with B-vitamins is important for prevention of vascular disease, principally in the long term. (C) 2010 Elsevier Inc. All rights reserved.