952 resultados para SYNAPTIC HOMEOSTASIS


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Objective: To elucidate the potential mechanisms involved in the physiopathology of endometriosis. We analyzed the differential gene expression profiles of eutopic and ectopic tissues from women with endometriosis. Design: Prospective laboratory study. Setting: University hospital. Patient(s): Seventeen patients in whom endometriosis was diagnosed and 11 healthy fertile women. Intervention(s): Endometrial biopsy specimens from the endometrium of healthy women without endometriosis and from the eutopic and ectopic endometrium tissues of patients with endometriosis were obtained in the early proliferative phase of the menstrual cycle. Main Outcome Measure(s): Six paired samples of eutopic and ectopic tissue were analyzed by subtractive hybridization. To evaluate the expression of genes found by rapid subtraction hybridization methods, we measured CTGF, SPARC, MYC, MMP and IGFBP1 genes by real-time polymerase chain reaction in all samples. Result(s): This study identified 291 deregulated genes in the endometriotic lesions. Significant expression differences were obtained for SPARC, MYC, and IGFBP1 in the peritoneal lesions and for MMP3 in the ovarian endometriomas. Additionally, significant differences were obtained for SPARC and IGFBP1 between the peritoneal and ovarian lesions. No significant differences were found for the studied genes between the control and the eutopic endometrium. Conclusion(s): This study identified 291 genes with differential expression in endometriotic lesions. The deregulation of the SPARC, MYC, MMP3, and IGFBP1 genes may be responsible for the loss of cellular homeostasis in endometriotic lesions. (Fertil Steril(R) 2010;93:1750-73. (C) 2010 by American Society for Reproductive Medicine.)

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Endometriosis is a gynecologic disease characterized by the presence of endometrial tissue outside the uterine cavity. Although 15% of the female population in reproductive age is affected by endometriosis, its pathogenesis remains unclear. According to the most accepted pathogenesis hypothesis, endometrial fragments from the menstrual phase are transported through the uterine tubes to the peritoneal cavity, where they undergo implantation and growth, invading adjacent tissues. However, the establishment of the disease requires that endometrial cells present molecular characteristics favoring the onset and progression of ectopic implantation. In this investigation, we analyzed the differential gene expression profiles of peritoneal and ovarian endometriotic lesions compared to the endometrial tissue of nonaffected women using rapid subtraction hybridization (RaSH). In our study, this method was applied to samples of endometriotic lesions from affected women and to biopsies of endometrium of healthy women without endometriosis, where we could identify 126 deregulated genes. To evaluate the expression of genes found by RaSH method, we measured LOXL1, HTRA1, and SPARC genes by real-time polymerase chain reaction. Significant different expression was obtained for HTRA1 and LOXL1, upregulated in the ectopic endometrium, suggesting that these genes are involved in the physiopathology of endometriosis and may favor the viability of endometrial cells at ectopic sites.

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Objective: To characterize the pattern of cell proliferation and apoptosis of eutopic and ectopic endometrium in rabbits after endometrium implantation for the experimental induction of endometriosis. Design: Animal experimental study. Setting: Sector of experimental surgery. Animal(s): Twenty-female New Zealand rabbits. Intervention(s): All animals underwent laparotomy for endometriosis induction by resection of one uterine horn, isolation of the endometrium, and fixation of tissue segment to the pelvic peritoneum. Two groups of 10 animals were sacrificed 4 and 8 weeks after endometriosis induction. The lesion was excised together with the opposite uterine horn for endometrial gland and stroma determination. Main Outcome Measure(s): Cell proliferation and apoptosis were determined in the eutopic and ectopic endometrium, and the cell proliferation index (CPI) and apoptotic index (AI) were calculated as the number of labeled cells per 1,000 cells. The tissue homeostasis index was the CPI/AI ratio. Glands and stroma were analyzed separately. Result(s): The CPI for ectopic tissue was increased compared with eutopic tissue, but there was no difference in the ectopic lesions between 4 and 8 weeks of induction. Considering only the AI, eutopic and ectopic endometrium did not differ after 4 weeks, but differed significantly in glandular tissue after 8 weeks. The tissue homeostasis index revealed cell proliferation in these tissues, with a CPI/AI more than 1. Conclusion(s): Ectopic lesions seem to have a higher CPI than eutopic endometrium, with uncontrolled tissue growth occurring in induced endometriotic lesions. (Fertil Steril (R) 2010;93:1637-42. (C)2010 by American Society for Reproductive Medicine.)

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Objective: To analyze the expression of the glycodelin gene to better understand the molecular environment of endometriotic lesions and to elucidate the potential mechanisms that underlie the complex physiopathology of endometriosis. Design: Prospective laboratory study. Setting: University hospital. Patient(s): Eleven healthy fertile women and 17 patients with endometriosis in the early proliferative phase of the menstrual cycle. Intervention(s): Endometrial biopsy specimens were obtained from the endometrium of healthy women without endometriosis (controls) and from eutopic and ectopic endometrium tissues (pelvic and ovarian endometriotic implants) of endometriosis patients. Main Outcome Measure(s): The glycodelin relative expression level by real-time polymerase chain reaction (PCR) analysis. Result(s): The glycodelin down-regulation found in the endometriotic lesions was 332.26 and 123.17-fold lower, respectively, when compared with the eutopic tissue and the control endometrium. Conclusion(s): Glycodelin may be one of the molecules that contributes to the loss of cellular homeostasis in endometriotic lesions. (Fertil Steril (R) 2009;91:1676-80. (C)2009 by American Society for Reproductive Medicine.)

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Introduction: Zinc is an essential element for human homeostasis being clearly related to almost all metabolic pathways. It is found in some neural circuitries, probably acting as a modulator of glutamatergic excitatory synapsis. In the auditory system its presence has been demonstrated within the cochlea and cochlear nuclei. Tinnitus symptoms are correlated to zinc physiology, and it has been postulated that the oligoelement could be used as an alternative treatment for this clinical situation. Aim: This study has evaluated the brainstem responses (ABR) in patients who suffer from chronic idiophatic tinnitus, before and after being treated with zinc. Neural transmissions in the brainstem auditory structures were also compared in both conditions. Materials and Methods: Forty-one patients (22 with tinnitus and 19 controls, groups I and II, respectively) were included in the study and submitted to anamnesis, otorhinolaryngologic examinations, biochemical evaluation and audiological tests. Group I patients received an specific zinc formulation for 90 days. ABR tests were performed at the beginning of the study and at the end of the zinc treatment. Results: First ABR tests showed no differences between the groups, but on the second evaluation there was a significant prolongation of the wave V latency and an enlargement of wave V amplitude shown in group I. Conclusion: Treatment with systemic zinc could change some aspects of auditory neurotransmission in the brainstem.

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Context The association between large for gestational age (LGA) phenotype, postnatal growth and cardiometabolic risk (CMR) in adult life remains unclear. The role of IGF1 genotype on LGA-related outcomes in adult life is unknown. Aim To assess the postnatal growth, IGF-I levels, CMR and the influence of the 737.738 IGF1 in adults born LGA. Subjects Case-control study (n = 515) nested in a population-based prospective cohort (n = 2063); 117 LGA and 398 gender-matched controls appropriate for gestational age (AGA) subjects. Methods Anthropometry was evaluated at birth, at 9-10 and at 23-25 years old. At the age of 23-25 years, blood pressure (BP), glycaemia, insulinaemia, homeostasis model assessment - insulin resistance, lipids, fibrinogen, and plasma IGF-I and 737.738 IGF1 polymorphism were assessed. Results Large for gestational age subjects remained heavier and taller than AGA at 9-10 and 23-25 years (P < 0.05); at 23-25 years, LGA had greater waist circumference (WC; P < 0.05) and higher BP (P < 0.05) than controls. Body proportionality at birth did not predict metabolic outcome. LGA subjects presenting catch-down of weight in childhood had lower body mass index (BMI; P = 0.001), lower WC (P < 0.05) and lower BP (P < 0.05) at 2325 years. 737.738 IGF-I genotype differed between groups (P < 0.001). Homozygosis for polymorphic alleles was associated with increased odds of LGA (OR: 3.2; 95% CI: 1.5-6.9), higher IGF-I (56.9 +/- 16.4 vs 37.7 +/- 16.0 nm; P < 0.01) and lower BP (114/68 vs 121/73 mmHg; P < 0.05). Conclusions Young adults born LGA presented higher BMI, WC and BP and appear to be at higher CMR risk than AGA subjects. The 737.738 IGF1 polymorphism appears to play a role on birth size and LGA-related metabolic outcomes.

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Objective: To assess whether the -11391G > A polymorphism in the regulatory region of the adiponectin gene (ADIPOQ) is associated with birth size, postnatal growth, adiponectinemia, and cardiometabolic risk in adult life. Design: Case-control study nested within a prospective cohort of 2063 community subjects born in 1978/1979 and followed since birth to date. Methods: ADIPOQ -11391G > A genotype-phenotype associations were evaluated in 116 subjects born large for gestational age (LGA) and 392 gender-matched controls at birth (birth size), at 8-10 years (catch-down growth), and at 23-25 years of age (cardiometabolic profile). Results: The -11391A variant allele frequency was higher in LGA subjects (P=0.04). AA genotype was associated with augmented probability of being born LGA (odds ratio=4.14; 95% confidence interval: 1.16-16.7; P=0.03). This polymorphism was associated neither with body composition nor with postnatal growth pattern. At the age of 23-25 years, the -11391A variant allele was associated with higher serum adiponectin levels (GG: 10.7 +/- 6.2 versus GA: 12.2 +/- 6.5 versus AA: 14.2 +/- 6.8 mu g/ml; P < 0.01). Subjects born LGA presented higher body mass index (BMI; P=0.01), abdominal circumference (P=0.04), blood pressure (P=0.04), and homeostasis assessment model for insulin resistance (P=0.01) than adequate for gestational age. Symmetry at birth did not influence these variables. The occurrence of catch-down of weight was associated with lower BMI and abdominal circumference (P < 0.001) at 23-25 years. Conclusions: The -11391A ADIPOQ gene variant was associated with increased chance of being born LGA and with higher adiponectin levels in early adult life.

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Background Little progress has been made to identify the central neuroendocrine pathway involved in the energy intake control in nonalcoholic fatty liver disease (NAFLD) patients. Objective To assess the influence of orexigenic neuropeptides in the nutritional aspects of NAFLD obese adolescents submitted to a long-term interdisciplinary approach. Methods Fifty adolescents aged 15-19 years, with body mass index at least 95th percentile, consisting of 25 patients without NAFLD and 25 with NAFLD. The NAFLD diagnosis was determined by ultrasonography. Blood samples were collected to analyze glycemia, hepatic transaminases, and lipid profile. Insulin resistance was estimated by Homeostasis Model Assessment Insulin Resistance Index. Neuropeptide Y (NPY) and agouti related protein concentrations were measured by enzyme-linked immunosorbent assay. Analyses of food intake were made by 3 days recordatory inquiry. Results At baseline conditions, the patients with NAFLD had significantly higher values of body mass, body mass index, visceral fat, triglycerides, VLDL-C, and hepatic transaminases. After the long-term intervention, they presented a significant reduction in these parameters. In both the groups, it was observed a significant decrease in energy intake, macronutrients and dietetic cholesterol. Only the patients with NAFLD presented a positive correlation between the saturated fatty acids intake and the orexigenic neuropeptides NPY and agouti related protein, and carbohydrate with NPY. Indeed, it was observed a positive correlation between energy intake, lipid (%) and saturated fatty acids with visceral fat accumulation. Conclusion Our findings showed an important influence of diet composition in the orexigenic system, being essential consider that the excessive saturated fatty acids intake could be a determinant factor to increase nonalcoholic fatty liver disease. Eur J Gastroenterol Hepatol 22:557-563 (C) 2010 Wolters Kluwer Health | Lippincott Williams & Wilkins.

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Muscle degenerative diseases such as Duchenne Muscular Dystrophy are incurable and treatment options are still restrained. Understanding the mechanisms and factors responsible for muscle degeneration and regeneration will facilitate the development of novel therapeutics. Several recent studies have demonstrated that Galectin-1 (Gal-1), a carbohydrate-binding protein, induces myoblast differentiation and fusion in vitro, suggesting a potential role for this mammalian lectin in muscle regenerative processes in vivo. However, the expression and localization of Gal-1 in vivo during muscle injury and repair are unclear. We report the expression and localization of Gal-1 during degenerative-regenerative processes in vivo using two models of muscular dystrophy and muscle injury. Gal-1 expression increased significantly during muscle degeneration in the murine mdx and in the canine Golden Retriever Muscular Dystrophy animal models. Compulsory exercise of mdx mouse, which intensifies degeneration, also resulted in sustained Gal-1 levels. Furthermore, muscle injury of wild-type C57BL/6 mice, induced by BaCl(2) treatment, also resulted in a marked increase in Gal-1 levels. Increased Gal-1 levels appeared to localize both inside and outside the muscle fibers with significant extracellular Gal-1 colocalized with infiltrating CD45(+) leukocytes. By contrast, regenerating muscle tissue showed a marked decrease in Gal-1 to baseline levels. These results demonstrate significant regulation of Gal-1 expression in vivo and suggest a potential role for Gal-1 in muscle homeostasis and repair.

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Background: Metabolic syndrome (MS) prevalence between different populations in obese adolescents is scanty to date. Objective: To compare the MS prevalence and related risk factors in Brazilian and Italian obese adolescents. Methods: A total of 509 adolescents (110 Brazilian, 399 Italian), aged 15-19 years. Anthropometric characteristics, triglycerides (TG), total, low-density lipoprotein (LDL)-, high-density lipoprotein (HDL)-cholesterol, fasting plasma glucose (FPG), insulin, homeostasis model assessment of insulin resistance (HOMA-IR) and blood pressure were measured. Results: Age, body mass index (BMI) and BMI z-score were not significantly different between the two subgroups. BMI z-score, TG, FPG, HOMA-IR and systolic blood pressure (SBP) were significantly higher in boys than in girls both in Brazilian and Italian adolescents, while HDL-cholesterol levels were lower in boys than in girls. No significant differences were observed in BMI, LDL and total-cholesterol and DBP in two genders and groups. Insulin, FPG, HOMA-IR and TG were significantly higher, while LDL-cholesterol and SBP were significantly lower in Brazilian than in Italian subjects, both in males and females. HDL and total-cholesterol and diastolic blood pressure (DBP) were not significantly different between the two subgroups and genders. MS prevalence was higher in Brazilian than in Italian obese boys (34.8 vs. 23.6%, p < 0.001) and girls (15.6 vs. 12.5%, p < 0.01). The most frequently altered parameter was HOMA-IR both in subjects with MS (100% in Brazilian and 81.8% in Italian) and without MS (42.9% and 11.7%). Conclusion: Metabolic syndrome represents a worldwide emerging health problem in different ethnical populations, the alterations of the risk factors related to MS (different in their prevalence between different subgroups) being strictly linked to the degree of obesity.

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Background: Obestatin is a recently identified ghrelin gene product that was reported to inhibit appetite and gastric motility in contrast to ghrelin. We investigated fasting obestatin and ghrelin levels in patients with obesity and anorexia nervosa. Methods: Fasting plasma obestatin, acyl-ghrelin, desacyl-ghrelin, leptin, glucose serum adiponectin, and insulin were measured in 10 obese subjects, 11 restricting-type anorexics, and 11 control subjects. Results: Obese group had significantly lower levels of obestatin (p < .01), while anorexic group had significantly higher levels (p < .01). Obestatin was negatively correlated with body mass index (BMI) (r = -.74), glucose (r = -.56), insulin (r = -.55), leptin (r = -.66), and also with the homeostasis model assessment of insulin resistance (HOMA-R) (r = -.49) and was positively correlated with acyl-ghrelin (r = .65) and desacyl-ghrelin (r = .60). No correlation was seen between obestatin and adiponectin, but the latter was negatively correlated with both acyl-ghrelin and desacyl-ghrelin. Desacyl-ghrelin to acyl-ghrelin ratio was significantly different between anorexic and control groups (p < .05), while no difference was seen between obese and control groups. Conclusions: Both obestatin and ghrelin are increased in anorexic and decreased in obesity. We suggest that obestatin is a nutritional marker reflecting body adiposity and insulin resistance.

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Purpose: To evaluate the clinical and hippocampal histological features of patients with mesial temporal lobe epilepsy (MTLE) in both familial (FMTLE) and sporadic (SMTLE) forms. Methods: Patients with FMTLE (n = 20) and SMTLE (n = 39) who underwent surgical treatment for refractory seizures were studied at the University of Sao Paulo School of Medicine at Ribeirao Preto. FMTLE was defined when at least two individuals in a family had clinical diagnosis of MTLE. Hippocampi from all patients were processed for Nissl/HE and Timm`s stainings. Both groups were compared for clinical variables, hippocampal cell densities, and intensity of supragranular mossy fiber staining. Results: There were no significant differences between FMTLE and SMTLE groups in the following: age at the surgery, age of first usual epileptic seizure, history of initial precipitating injury (IPI), age of IPI, latent period, ictal and interictal video-EEG patterns, presence of hippocampal atrophy and signal changes at MRI, and postoperative outcome. In addition, no differences were found in cell densities in hippocampal cornu ammonis subfields (CA1, CA2, CA3, CA4), fascia dentata, polymorphic region, subiculum, prosubiculum, and presubiculum. However, patients with SMTLE had greater intensity of mossy fiber Timm`s staining in the fascia dentata-inner molecular layer (p < 0.05). Discussion: Patients with intractable FMTLE present a clinical profile and most histological findings comparable to patients with SMTLE. Interestingly, mossy fiber sprouting was less pronounced in patients with FMTLE, suggesting that, when compared to SMTLE, patients with FMTLE respond differently to plastic changes plausibly induced by cell loss, neuronal deafferentation, or epileptic seizures.

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The superior cervical ganglion (SCG) in mammals varies in structure according to developmental age, body size, gender, lateral asymmetry, the size and nuclear content of neurons and the complexity and synaptic coverage of their dendritic trees. In small and medium-sized mammals, neuron number and size increase from birth to adulthood and, in phylogenetic studies, vary with body size. However, recent studies on larger animals suggest that body weight does not, in general, accurately predict neuron number. We have applied design-based stereological tools at the light-microscopic level to assess the volumetric composition of ganglia and to estimate the numbers and sizes of neurons in SCGs from rats, capybaras and horses. Using transmission electron microscopy, we have obtained design-based estimates of the surface coverage of dendrites by postsynaptic apposition zones and model-based estimates of the numbers and sizes of synaptophysin-labelled axo-dendritic synaptic disks. Linear regression analysis of log-transformed data has been undertaken in order to establish the nature of the relationships between numbers and SCG volume (V(scg)). For SCGs (five per species), the allometric relationship for neuron number (N) is N=35,067xV (scg) (0.781) and that for synapses is N=20,095,000xV (scg) (1.328) , the former being a good predictor and the latter a poor predictor of synapse number. Our findings thus reveal the nature of SCG growth in terms of its main ingredients (neurons, neuropil, blood vessels) and show that larger mammals have SCG neurons exhibiting more complex arborizations and greater numbers of axo-dendritic synapses.

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In this study the main question investigated was the number and size of both binucleate and mononucleate superior cervical ganglion (SCG) neurons and, whether post-natal development would affect these parameters. Twenty left SCGs from 20 male pacas were used. Four different ages were investigated, that is newborn (4 days), young (45 days), adult (2 years), and aged animals (7 years). By using design-based stereo-logical methods, that is the Cavalieri principle and a physical disector combined with serial sectioning, the total volume of ganglion and total number of mononucleate and binucleate neurons were estimated. Furthermore, the mean perikaryal (somal) volume of mononucleate and binucleate neurons was estimated using the vertical nucleator. The main findings of this study were a 154% increase in the SCG volume, a 95% increase in the total number of mononucleate SCG neurons and a 50% increase in the total volume of SCG neurons. In conclusion, apart from neuron number, different adaptive mechanisms may coexist in the autonomic nervous system to guarantee a functional homeostasis during ageing, which is not always associated with neuron losses. Anat Rec, 292:966-975, 2009. (C) 2009 Wiley-Liss, Inc.

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The nerve terminals of intrinsic muscular fibers of the tongue of adult wistar rats was studied by using silver impregnation techniques, transmission electron microscopy (TEM), and high resolution scanning electron microscopy (HRSEM) to observe the nerve fibers and their terminals. Silver impregnation was done according to Winkelman and Schmit, 1957. For TEM, small blocks were fixed in modified Karnovsky solution, postfixed in 1% buffered osmium tetroxide solution, and embedded in Spurr resin. For HRSEM, the parts were fixed in 2% osmium tetroxide solution with 1/15 M sodium phosphate buffer (pH 7.4) at 4 degrees C for 2 h, according to the technique described by Tanaka, 1989. Thick myelinated nerve bundles were histologically observed among the muscular fibers. The intrafusal nerve fiber presented a tortuous pathway with punctiform terminal axons in clusters contacting the surface of sarcolemma. Several myelinated nerve fibers involved by collagen fibers of the endoneurium were observed in HRSEM in three-dimensional aspects. The concentric lamellae of the myelin sheath and the axoplasm containing neurofilaments interspersed among the mitochondria were also noted. In TEM, myofibrils, mitochondria, rough endoplasmic reticulum, Golgi`s apparatus, and glycogen granules were observed in sarcoplasm. It is also noted that the sarcomeres constituted by myofilaments with their A, I, and H bands and the electron dense Z lines. In areas adjacent to muscular fibers, there were myelinated and unmyelinated nerve fibers involved by endoneurium and perineurium. In the region of the neuromuscular junction, the contact with the sarcolemma of the muscular cell occurs forming several terminal buttons and showing numerous evaginations of the cell membrane. In the terminal button, mitochondria and numerous synaptic vesicles were observed. Microsc. Res. Tech. 72:464-470, 2009. (C) 2009 Wiley-Liss. Inc.