965 resultados para BASAL GANGLIA
Resumo:
We have compared the effects of two types of physical training on the cardiac autonomic control in ovariectomized and sham-operated rats according to different approaches: double autonomic blockade (DAB) with methylatropine and propranolol; baroreflex sensibility (BRS) and spectral analysis of heart rate variability (HRV). Wistar female rats (+/- 250 g) were divided into two groups: sham-operated and ovariectomized. Each group was subdivided into three subgroups: sedentary rats, rats submitted to aerobic trained and rats submitted to resistance training. Ovariectomy did not change arterial pressure, basal heart rate (HR), DAB and BRS responses, but interfered with HRV by reducing the low-frequency oscillations (LF = 0.20-0.75 Hz) in relation to sedentary sham-operated rats. The DAB showed that both types of training promoted an increase in the predominance of vagal tonus in sham-operated rats, but HR variations due to methylatropine were decreased in the resistance trained rats compared to sedentary rats. Evaluation of BRS showed that resistance training for sham-operated and ovariectomized rats reduced the tachycardic responses in relation to aerobic training. Evaluation of HRV in trained rats showed that aerobic training reduced LF oscillations in sham-operated rats, whereas resistance training had a contrary effect. In the ovariectomized rats, aerobic training increased high frequency oscillations (HF = 0.75-2.5 Hz), whereas resistance training produced no effect. In sham-operated rats, both types of training increased the vagal autonomic tonus, but resistance training reduced HF oscillations and BRS as well. In turn, both types of training had similar results in ovariectomized rats, except for HRV, as aerobic training promoted an increase in HF oscillations. (C) 2011 Elsevier B.V. All rights reserved.
Resumo:
This study was conducted in one kidney, one clip (1K1C) Goldblatt hypertensive rats to evaluate vascular and cardiac autonomic control using different approaches: 1) evaluation of the autonomic modulation of heart rate (HR) and systolic arterial pressure (SAP) by means of autoregressive power spectral analysis 2) assessment of the cardiac baroreflex sensitivity; and 3) double blockade with methylatropine and propranolol. The 1K1C group developed hypertension and tachycardia. The 1K1C group also presented reduction in variance as well as in LF (0.23 +/- 0.1 vs. 1.32 +/- 0.2 ms(2)) and HF (6.6 +/- 0.49 vs. 15.1 +/- 0.61 ms(2)) oscillations of pulse interval. Autoregressive spectral analysis of SAP showed that 1K1C rats had an increase in variance and LF band (13.3 +/- 2.7 vs. 7.4 +/- 1.01 mmHg(2)) in comparison with the sham group. The baroreflex gain was attenuated in the hypertensive 1K1C (- 1.83 +/- 0.05 bpm/mmHg) rats in comparison with normotensive sham (-3.23 +/- 0.06 bpm/MmHg) rats. The autonomic blockade caused an increase in the intrinsic HR and sympathetic predominance on the basal HR of 1K1C rats. Overall, these data indicate that the tachycardia observed in the 1K1C group may be attributed to intrinsic cardiac mechanisms (increased intrinsic heart rate) and to a shift in the sympathovagal balance towards cardiac sympathetic over-activity and vagal suppression associated to depressed baroreflex sensitivity. Finally, the increase in the LF components of SAP also suggests an increase in sympathetic activity to peripheral vessels. (c) 2008 Elsevier B.V. All rights reserved.
Resumo:
Objective: To evaluate the effect of peritoneal fluid (PF) from women without and with minimal/mild endometriosis on progesterone (P) release by cultured human granulosa-lutein cells obtained from infertile patients without endometriosis submitted to ovarian hyperstimulation for in vitro fertilization (IVF). Study design: A pilot study was performed. Human granulosa-lutein cells, obtained from 11 infertile patients without endometriosis (tubal or male factors of infertility) submitted to ovarian hyperstimulation for IVF, were cultured without PF (basal production) and with increasing volumes of steroid-extracted PF samples from 11 patients with endometriosis and 11 patients without endometriosis. Progesterone (P) levels in the media after 72 h culture were measured by chemoluminescence assay. The non-parametric Mann-Whitney-test was used for statistical analysis. Results: PF from patients without endometriosis stimulated P release in a dose-dependent manner up to the dose of 100 mu l/ml (10% concentration) when compared with basal production (without adding PF). P release was similar in cultures stimulated with PF from patients with or without endometriosis at 1% (10 mu l/ml) and 5% (50 ml/ml) concentrations. At 10% concentration, there was a non-statistically significant reduction in progesterone release by granulosa cells stimulated with PF from patients with endometriosis. PF from patients with endometriosis significantly reduced P release at 30% concentration (300 mu l/ml). Conclusions: PF stimulates P release by human granulosa-lutein cells in a dose-dependent manner. However, higher concentrations of PF from patients with minimal/mild endometriosis reduce P release, suggesting it contains factors that may compromise ovarian steroidogenesis. (c) 2007 Elsevier Ireland Ltd. All rights reserved.
Resumo:
The study of lingual surfaces and the surface of interface epithelium-connective tissue of the tongue of Bradypus torquatus was performed by employing the light and scanning electron microscopy (SEM) techniques. The results revealed that the rostral part of the tongue presents a round apex and covered by filiform and fungiform lingual papillae and a ventral smooth surface. It was observed that the epithelial layer of the dorsal surface possesses the basal, spinosum, granular and cornified epithelial cells. The lamina propria is characterized by a dense connective tissue forming the long, short and round papillae. Numerous typical filiform papillae are located especially in the rostral part intermingled for few fungiform papillae, which were revealed in three-dimensional SEM images. Usually, the fungiform papillae are located in the border of rostral apex of the tongue exhibiting the rounded form. They are covered by keratinized epithelial cells. In the fungiform papillae, several taste pores were observed on the surface. The vallate papillae presented numerous taste buds in the wall of epithelial cells, being that the major number of taste buds is located on the superior half of vallate papilla. The taste pores are surrounded by several laminae of keratinized epithelial cells. The samples treated with NaOH solution and examined by SEM revealed, after removal of the epithelial layer, the dense connective core in original disposition, presenting different sizes and shapes. The specimens stained with Picrosirius and examined by polarized light microscopy revealed the connective tissue, indicating the collagen fibres type I and type III.
Resumo:
Objective-To evaluate the efficacy of cryosurgery for treatment of skin and subcutaneous tumors in dogs and cats. Study Design-Prospective study. Animals-Dogs (n = 20), cats (10). Methods-Cutaneous or subcutaneous tumors were treated by liquid nitrogen cryosurgical spray (1 cm from target tissue at 90 degrees until a 5-mm halo of frozen tissue was achieved) for 15-60 seconds. Malignant lesions had 3 freeze-thaw cycles benign tumors, 2 cycles. The second or third freeze cycle was performed after complete thaw of the preceding freeze. Wounds healed by second intention. Follow-up was weekly for 1 month and then twice monthly until wounds healed, and final outcome was determined by telephone interview of owners. Results-Tumor size ranged from 0.3 to 11 cm, diameter with 28 (60%) being 0.3-1 cm; 8 (17%) 1.1-3cm, and 11 (23%) >3.4cm. Complications included edema, erythema and for extremity lesions, pain and lameness. Treated lesions (n = 47) had an overall remission of 98% (mean follow-up.. 345 +/- 172.02 days [range, 150-750 days]). One malignant peripheral nerve sheath tumor recurred 7 months after cryosurgical treatment. Conclusion-Cryo surgery is an efficient method for treatment of skin and subcutaneous tumors in dogs and cats. Clinical Relevance-Cryosurgical ablation is an effective means of treating small cutaneous or subcutaneous tumors in dogs and cats, especially in older animals where wound closure or cosmetic outcome might limit surgical excision alone. (C) Copyright 2008 by The American College of Veterinary Surgeons.