7 resultados para Selective breeding program


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To further understand the pharmacological properties of N-oleoylethanolamine (OEA), a naturally occurring lipid that activates peroxisome proliferator-activated receptor alpha (PPARα), we designed sulfamoyl analogs based on its structure. Among the compounds tested, N-octadecyl-N'-propylsulfamide (CC7) was selected for functional comparison with OEA. The performed studies include the following computational and biological approaches: 1) molecular docking analyses; 2) molecular biology studies with PPARα; 3) pharmacological studies on feeding behavior and visceral analgesia. For the docking studies, we compared OEA and CC7 data with crystallization data obtained with the reference PPARα agonist GW409544. OEA and CC7 interacted with the ligand-binding domain of PPARα in a similar manner to GW409544. Both compounds produced similar transcriptional activation by in vitro assays, including the GST pull-down assay and reporter gene analysis. In addition, CC7 and OEA induced the mRNA expression of CPT1a in HpeG2 cells through PPARα and the induction was avoided with PPARα-specific siRNA. In vivo studies in rats showed that OEA and CC7 had anorectic and antiobesity activity and induced both lipopenia and decreases in hepatic fat content. However, different effects were observed when measuring visceral pain; OEA produced visceral analgesia whereas CC7 showed no effects. These results suggest that OEA activity on the PPARα receptor (e.g., lipid metabolism and feeding behavior) may be dissociated from other actions at alternative targets (e.g., pain) because other non cannabimimetic ligands that interact with PPARα, such as CC7, do not reproduce the full spectrum of the pharmacological activity of OEA. These results provide new opportunities for the development of specific PPARα-activating drugs focused on sulfamide derivatives with a long alkyl chain for the treatment of metabolic dysfunction.

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In recent years it has been shown that emotional stress induced by immobilization may change the balance between pro-oxidant and antioxidant factors inducing oxidative damage. On the other hand, contradictory views exist concerning the role of physical activity on redox metabolism. Consequently, the present work was designed to assess the influence of an 8-week moderate swimming training program in emotionally stressed rats. Sixty 1-month-old male albino Wistar rats weighing 125-135 g were used in this experimental study. They were divided into three groups, as Control (lot A; n=20), Stressed (lot B; n=20) and Stressed & Exercised (lot C; n=20). Rats were stressed by placing the animals in a 25 x 7 cm plastic bottle 1 h/day, 5 days a week for 8 weeks. Protein carbonyl content values in liver homogenates were significantly increased in stressed animals (0.58+/-0.02 vs 0.86+/-0.03; p=0.018) which clearly indicated that emotional stress was associated with oxidative stress. Ultrastructural alterations, predominantly mitochondrial swelling and the decrease of cristae number observed by electron microscopy represented direct evidence of membrane injury. The most striking feature of our study was that we also found differences between stressed rats and stressed rats that performed our 8 week training program. Consequently our results highlight the potential benefit of a moderate training program to reduce oxidative damage induced by emotional stress since it attenuated protein oxidation and mitochondrial alterations.

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In autoimmune type 1 diabetes mellitus, proinflammatory cytokine-mediated apoptosis of beta-cells has been considered to be the first event directly responsible for beta-cell mass reduction. In the Bio-Breeding (BB) rat, an in vivo model used in the study of autoimmune diabetes, beta-cell apoptosis is observed from 9 wk of age and takes place after an insulitis period that begins at an earlier age. Previous studies by our group have shown an antiproliferative effect of proinflammatory cytokines on cultured beta-cells in Wistar rats, an effect that was partially reversed by Exendin-4, an analogue of glucagon-like peptide-1. In the current study, the changes in beta-cell apoptosis and proliferation during insulitis stage were also determined in pancreatic tissue sections in normal and thymectomized BB rats, as well as in Wistar rats of 5, 7, 9, and 11 wk of age. Although stable beta-cell proliferation in Wistar and thymectomized BB rats was observed along the course of the study, a decrease in beta-cell proliferation and beta-cell mass from the age of 5 wk, and prior to the commencement of apoptosis, was noted in BB rats. Exendin-4, in combination with anti-interferon-gamma antibody, induced a near-total recovery of beta-cell proliferation during the initial stages of insulitis. This highlights the importance of early intervention and, as well, the possibilities of new therapeutic approaches in preventing autoimmune diabetes by acting, initially, in the insulitis stage and, subsequently, on beta-cell regeneration and on beta-cell apoptosis.

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BACKGROUND In cervical postoperative radiotherapy, the target volume is usually the same as the extension of the previous dissection. We evaluated a protocol of selective irradiation according to the risk estimated for each dissected lymph node level. METHODS Eighty patients with oral/oropharyngeal cancer were included in this prospective clinical study between 2005 and 2008. Patients underwent surgery of the primary tumor and cervical dissection, with identification of positive nodal levels, followed by selective postoperative radiotherapy. Three types of selective nodal clinical target volume (CTV) were defined: CTV0, CTV1, and CTV2, with a subclinical disease risk of <10%, 10-25%, and 25% and a prescribed radiation dose of <35 Gy, 50 Gy, and 66-70 Gy, respectively. The localization of node failure was categorized as field, marginal, or outside the irradiated field. RESULTS A consistent pattern of cervical infiltration was observed in 97% of positive dissections. Lymph node failure occurred within a high-risk irradiated area (CTV1-CTV2) in 12 patients, marginal area (CTV1/CTVO) in 1 patient, and non-irradiated low-risk area (CTV0) in 2 patients. The volume of selective lymph node irradiation was below the standard radiation volume in 33 patients (mean of 118.6 cc per patient). This decrease in irradiated volume was associated with greater treatment compliance and reduced secondary toxicity. The three-year actuarial nodal control rate was 80%. CONCLUSION This selective postoperative neck irradiation protocol was associated with a similar failure pattern to that observed after standard neck irradiation and achieved a significant reduction in target volume and secondary toxicity.

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OBJECTIVE: To evaluate nutritional status and dietary habits after implementation of a nutritional education program in professional handball players. RESEARCH METHODS AND PROCEDURES: Longitudinal study of 14 handball players evaluated with 72-h recall, a questionnaire on food consumption and anthropometric measures during 4 months. The intervention consisted of a nutrition education program. RESULTS: Energy intake was consistently below the recommended allowances. Macronutrient intakes as a percentage of total energy intake were below the recommended allowances for carbohydrates, and above recommended allowances for fats. Nutritional education was followed by a significant increase (p < 0.01) in total energy and macronutrient intakes, with no significant changes in macronutrient or micronutrient intakes after adjustment for energy intake. DISCUSSION: The imbalance in nutrient intake in handball players suggests that detailed re-analysis is needed to determine specific recommendations for this population. Nutritional education with continuous follow-up to monitor athletes' dietary habits may lead them to adopt appropriate nutritional habits to optimize dietary intakes. The lack of specific recommendations for micronutrient intakes in athletes leads to confusion regarding appropriate intakes; biochemical tests that yield normal values (albeit approaching cut-off values for deficiency) may disguise deficient status for some nutrients when strenuous exercise is involved. CONCLUSION: In-depth studies with nutrition education programs that include long-term follow-up are advisable to avoid deficiencies that can lead to irreversible damage in competitive athletes.

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Oleoylethanolamide (OEA) is an agonist of the peroxisome proliferator-activated receptor α (PPARα) and has been described to exhibit neuroprotective properties when administered locally in animal models of several neurological disorder models, including stroke and Parkinson's disease. However, there is little information regarding the effectiveness of systemic administration of OEA on Parkinson's disease. In the present study, OEA-mediated neuroprotection has been tested on in vivo and in vitro models of 6-hydroxydopamine (6-OH-DA)-induced degeneration. The in vivo model was based on the intrastriatal infusion of the neurotoxin 6-OH-DA, which generates Parkinsonian symptoms. Rats were treated 2 h before and after the 6-OH-DA treatment with systemic OEA (0.5, 1, and 5 mg/kg). The Parkinsonian symptoms were evaluated at 1 and 4 wk after the development of lesions. The functional status of the nigrostriatal system was studied through tyrosine-hydroxylase (TH) and hemeoxygenase-1 (HO-1, oxidation marker) immunostaining as well as by monitoring the synaptophysin content. In vitro cell cultures were also treated with OEA and 6-OH-DA. As expected, our results revealed 6-OH-DA induced neurotoxicity and behavioural deficits; however, these alterations were less severe in the animals treated with the highest dose of OEA (5 mg/kg). 6-OH-DA administration significantly reduced the striatal TH-immunoreactivity (ir) density, synaptophysin expression, and the number of nigral TH-ir neurons. Moreover, 6-OH-DA enhanced striatal HO-1 content, which was blocked by OEA (5 mg/kg). In vitro, 0.5 and 1 μM of OEA exerted significant neuroprotection on cultured nigral neurons. These effects were abolished after blocking PPARα with the selective antagonist GW6471. In conclusion, systemic OEA protects the nigrostriatal circuit from 6-OH-DA-induced neurotoxicity through a PPARα-dependent mechanism.

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BACKGROUND The high prevalence of women that do not reach the recommended level of physical activity is worrisome. A sedentary lifestyle has negative consequences on health status and increases health care costs. The main objective of this project is to assess the cost-effectiveness of a primary care-based exercise intervention in perimenopausal women. METHODS/DESIGN The present study is a Randomized Controlled Trial. A total of 150 eligible women will be recruited and randomly assigned to either a 16-week exercise intervention (3 sessions/week), or to usual care (control) group. The primary outcome measure is the incremental cost-effectiveness ratio. The secondary outcome measures are: i) socio-demographic and clinical information; ii) body composition; iii) dietary patterns; iv) glycaemic and lipid profile; v) physical fitness; vi) physical activity and sedentary behaviour; vii) sleep quality; viii) quality of life, mental health and positive health; ix) menopause symptoms. All outcomes will be assessed at baseline and post intervention. The data will be analysed on an intention-to-treat basis and per protocol. In addition, we will conduct a cost effectiveness analysis from a health system perspective. DISCUSSION The intervention designed is feasible and if it proves to be clinically and cost effective, it can be easily transferred to other similar contexts. Consequently, the findings of this project might help the Health Systems to identify strategies for primary prevention and health promotion as well as to reduce health care requirements and costs. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT02358109 . Date of registration: 05/02/2015.