57 resultados para Pituitary Gland, Anterior

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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Although snake infralabial glands are generally constituted of mucous cells, among dipsadines, they are much more developed and predominantly serous in nature, possibly due to the peculiar feeding habits of some species of this group, the ""goo-eaters"", which feed on soft and viscous invertebrates. We compared the morphology and histochemistry of the infralabial glands of three goo-eater species of Southeast Brazil, Atractus reticulatus, Dipsas indica and Sibynomorphus mikanii. In A. reticulatus the glands are formed by mixed acini composed of mucous and seromucous cells and in D. indica, they are composed of mucous tubules and seromucous acini. In S. mikanii the glands are organized in seromucous acini; mucous cells are restricted to the gland anterior region and to the duct lining epithelium. Ultrastructurally, secretory granule electron density varies from low to moderate, depending on their mucous or seromucous nature. The results indicate a large morphological and histochemical variation in the infralabial glands, probably reflecting differences in the secretion chemical composition and in feeding specialization among the three species. The protein content in the secretory cells can be related with the presence of toxins that can be used in chemical prey immobilization or detaching of snails from their shells. (c) 2007 Elsevier Ltd. All rights reserved.

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Sexual differentiation in the brain takes place from late gestation to the early postnatal days. This is dependent on the conversion of circulating testosterone into estradiol by the enzyme aromatase. The glyphosate was shown to alter aromatase activity and decrease serum testosterone concentrations. Thus, the aim of this study was to investigate the effect of gestational maternal glyphosate exposure (50 mg/kg, NOAEL for reproductive toxicity) on the reproductive development of male offspring. Sixty-day-old male rat offspring were evaluated for sexual behavior and partner preference; serum testosterone concentrations, estradiol, FSH and LH; the mRNA and protein content of LH and FSH; sperm production and the morphology of the seminiferous epithelium; and the weight of the testes, epididymis and seminal vesicles. The growth, the weight and age at puberty of the animals were also recorded to evaluate the effect of the treatment. The most important findings were increases in sexual partner preference scores and the latency time to the first mount; testosterone and estradiol serum concentrations; the mRNA expression and protein content in the pituitary gland and the serum concentration of LH; sperm production and reserves; and the height of the germinal epithelium of seminiferous tubules. We also observed an early onset of puberty but no effect on the body growth in these animals. These results suggest that maternal exposure to glyphosate disturbed the masculinization process and promoted behavioral changes and histological and endocrine problems in reproductive parameters. These changes associated with the hypersecretion of androgens increased gonadal activity and sperm production.

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Lymphocytic hypophysitis (LH) has been described previously in systemic lupus erythematosus (1.3%), Sjogren's syndrome (0.8%). Lymphocytic hypo physitis (LH) is rarely associated with rheumatic diseases, although three cases of pituitary disease associated with antiphospholipid syndrome (APS) have been described. Here, we report a possible association between APS and LH for the first time. A 34-yr-old woman with primary APS presented with polyuria, polydipsia, hypernatremia and impaired vision. Her hormone profile was compatible with panhypopituitarism, and sellar magnetic resonance imaging (MRI) depicted a normal pituitary gland with a thickened and displaced stalk and infundibulum portion. Hormone replacement was started, and the patient experienced a good clinical evolution.

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Objectives: To report a case of multifocal fibrosclerosis with a nine-year follow up, and to discuss this disease's radiological appearance and management. The disease is a rare systemic disorder of unknown cause characterised by fibrous proliferation involving multiple anatomical sites. Case report: A 50-year-old woman presented with histological findings characterised by similar inflammatory processes involving the meninges, pituitary gland, peritoneum, retroperitoneum and orbits, prompting a search for a common pathophysiology. A diagnosis of multifocal fibrosclerosis was postulated. Symptom improvement was noted after treatment with prednisone and azathioprine. Conclusion: This is the first documented case of involvement of the cochleovestibular nerve in a patient with multifocal fibrosclerosis. The rare association between fibrotic diseases and masses showing various clinical patterns should be kept in mind by otolaryngologists, and imaging performed to investigate for multifocal fibrosclerosis. However, diagnosis can only be confirmed with tissue biopsy and histopathological examination.

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OBJETIVOS: Caracterizar as pacientes com valores indeterminados de hiperprolactinemia (teste de PEG para identificação de macroprolactinemias com recuperação entre 30 e 65%) (PRLi) ou macroprolactinemia (PRLm), quanto às características clínicas, como intensidade e variação dos sintomas e presença ou não de tumores no sistema nervoso central. MÉTODOS: Estudo transversal, retrospectivo, de levantamento de prontuários, no qual foram incluídas 24 pacientes com diagnóstico de hiperprolactinemia (PRL>25 ng/dL), em idade reprodutiva, em seguimento em ambulatório de ginecologia endócrina. Foram incluídas 11 pacientes com PRLm e 13 com PRLi. Dos dois grupos (PRLm e PRLi), foram considerados para a análise registros dos dados relativos à idade, à paridade, ao índice de massa corporal, à presença de galactorreia, à infertilidade e ao tumor do sistema nervoso central. Os dados antropométricos foram expressos em média e desvio padrão e, para a comparação entre os grupos quanto à presença de tumor no sistema nervoso central, galactorreia e infertilidade, utilizou-se o teste t de Student. RESULTADOS: A galactorreia foi mais prevalente nas pacientes com PRLi (p=0,01). Setenta por cento das mulheres com PRLi apresentaram microprolactinoma de hipófise, enquanto que este achado foi evidente em 17% das mulheres com PRLm (p=0,04). Dentre as pacientes com PRLm e PRLi, nove não foram investigadas com imagem do sistema nervoso central por apresentarem níveis pouco elevados de prolactina (cinco portadoras de PRLm e quatro de PRLi). Não houve diferença significativa quanto à ocorrência de infertilidade ou de ciclos menstruais irregulares. CONCLUSÕES: Mulheres com hiperprolactinemia intermediária apresentam mais sintomas de galactorreia e maior incidência de tumores do sistema nervoso central do que aquelas com macroprolactinemia.

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The extent to which the hypothalamic-pituitary-adrenal axis is activated by short-term and long-term consequences of stress is still open to investigation. This study aimed to determine (i) the correlation between plasma corticosterone and exploratory behavior exhibited by rats subjected to the elevated plus maze (EPM) following different periods of social isolation, (ii) the effects of the corticosterone synthesis blocker, metyrapone, on the behavioral consequences of isolation, and (iii) whether corticosterone produces its effects through an action on the anterior cingulate cortex, area 1 (Cg1). Rats were subjected to 30-min, 2-h, 24-h, or 7-day isolation periods before EPM exposure and plasma corticosterone assessments. Isolation for longer periods of time produced greater anxiogenic-like effects on the EPM. However, stretched attend posture (SAP) and plasma corticosterone concentrations were increased significantly after 30 min of isolation. Among all of the behavioral categories measured in the EPM, only SAP positively correlated with plasma corticosterone. Metyrapone injected prior to the 24 h isolation period reversed the anxiogenic effects of isolation. Moreover, corticosterone injected into the Cg1 produced a selective increase in SAP. These findings indicate that risk assessment behavior induced by the action of corticosterone on Cg1 neurons initiates a cascade of defensive responses during exposure to stressors.

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The tumorigenesis of pituitary adenomas is poorly understood. Mutations of the PIK3CA proto-oncogene, which encodes the p110-α catalytic subunit of PI3K, have been reported in various types of human cancers regarding the role of the gene in cell proliferation and survival through activation of the PI3K/Akt signaling pathway. Only one Chinese study described somatic mutations and amplification of the PIK3CA gene in a large series of pituitary adenomas. The aim of the present study was to determine genetic alterations of PIK3CA in a second series that consisted of 33 pituitary adenomas of different subtypes diagnosed by immunohistochemistry: 6 adrenocorticotropic hormone-secreting microadenomas, 5 growth hormone-secreting macroadenomas, 7 prolactin-secreting macroadenomas, and 15 nonfunctioning macroadenomas. Direct sequencing of exons 9 and 20 assessed by qPCR was employed to investigate the presence of mutations and genomic amplification defined as a copy number ≥4. Previously identified PIK3CA mutations (exon 20) were detected in four cases (12.1%). Interestingly, the Chinese study reported mutations only in invasive tumors, while we found a PIK3CA mutation in one noninvasive corticotroph microadenoma. PIK3CA amplification was observed in 21.2% (7/33) of the cases. This study demonstrates the presence of somatic mutations and amplifications of the PIK3CA gene in a second series of pituitary adenomas, corroborating the previously described involvement of the PI3K/Akt signaling pathway in the tumorigenic process of this gland.

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Proteases from the midgut gland of the Farfantepenaeus paulensis juveniles were assessed. Enzyme activity was determined using protease substrates and inhibitors. The effect of pH, temperature and calcium on proteolytic activity was assayed. Caseinolytic activity was analysed in substrate-sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Trypsin, chymotrypsin and leucine aminopeptidase activity was detected. Proteolytic activity was strongly inhibited by the specific trypsin inhibitors. Tosyl-phenylalanine chloromethyl ketone inhibited 59.3% of chymotrypsin activity. The greatest trypsin-like activity occurred at pH 8.0 and 45 degrees C. Chymotrypsin-like activity reached maximal values at alkaline pH (7.2-9.0) and 55 degrees C. CaCl(2) did not increase trypsin-like activity, but rather inhibited it at concentrations of 30 (20%), 50 (30%) and 100 mM (50%). The substrate-SDS-PAGE zymogram revealed eight proteinase bands. Two possibly thermal-resistant (85 degrees C, 30 min) chymotrypsin isoforms were found, which were inhibited by phenyl-methyl-sulphonyl-fluoride. Aminopeptidase activity of enzyme extracts (Arg, Leu, Lys, Phe and Val) and the recommended concentrations of these essential amino acids in penaeid shrimp diets were positively correlated (P < 0.05). Beause protein digestion involves the combined action of different enzymes, adequate knowledge of shrimp digestion and enzyme characteristics is required for the assessment of the digestive potential of different feed sources and development of in vitro digestibility protocols.

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Objective-Blood-sucking arthropods' salivary glands contain a remarkable diversity of antihemostatics. The aim of the present study was to identify the unique salivary anticoagulant of the sand fly Lutzomyia longipalpis, which remained elusive for decades. Methods and Results-Several L. longipalpis salivary proteins were expressed in human embryonic kidney 293 cells and screened for inhibition of blood coagulation. A novel 32.4-kDa molecule, named Lufaxin, was identified as a slow, tight, noncompetitive, and reversible inhibitor of factor Xa (FXa). Notably, Lufaxin's primary sequence does not share similarity to any physiological or salivary inhibitors of coagulation reported to date. Lufaxin is specific for FXa and does not interact with FX, Dansyl-Glu-Gly-Arg-FXa, or 15 other enzymes. In addition, Lufaxin blocks prothrombinase and increases both prothrombin time and activated partial thromboplastin time. Surface plasmon resonance experiments revealed that FXa binds Lufaxin with an equilibrium constant approximate to 3 nM, and isothermal titration calorimetry determined a stoichiometry of 1:1. Lufaxin also prevents protease-activated receptor 2 activation by FXa in the MDA-MB-231 cell line and abrogates edema formation triggered by injection of FXa in the paw of mice. Moreover, Lufaxin prevents FeCl3-induced carotid artery thrombus formation and prolongs activated partial thromboplastin time ex vivo, implying that it works as an anticoagulant in vivo. Finally, salivary gland of sand flies was found to inhibit FXa and to interact with the enzyme. Conclusion-Lufaxin belongs to a novel family of slow-tight FXa inhibitors, which display antithrombotic and anti-inflammatory activities. It is a useful tool to understand FXa structural features and its role in prohemostatic and proinflammatory events. (Arterioscler Thromb Vasc Biol. 2012;32:2185-2196.)

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Trypanosoma rangeli is the trypanosomatid that colonizes the salivary gland of its insect vector, with a profound impact on the feeding capacity of the insect. In this study we investigated the role of the phosphotyrosine (P-Tyr) ecto-phosphatase activity of T. rangeli in its interaction with Rhodnius prolixus salivary glands. Long but not short epimastigotes adhered to the gland cells and the strength of interaction correlated with the enzyme activity levels in different strains. Differential interference contrast microscopy demonstrated that clusters of parasites are formed in most cases, suggesting cooperative interaction in the adhesion process. The tightness of the correlation was evidenced by modulating the P-Tyr ecto-phosphatase activity with various concentrations of inhibitors. Sodium orthovanadate, ammonium molybdate and zinc chloride decreased the interaction between T. rangeli and R. prolixus salivary glands in parallel. Levamisole, an inhibitor of alkaline phosphatases, affected neither process. EDTA strongly inhibited adhesion and P-Tyr ecto-phosphatase activity to the same extent, an effect that was no longer seen if the parasites were pre-incubated with the chelator and then washed. When the P-Tyr ecto-phosphatase of living T. ranged epimastigotes was irreversibly inactivated with sodium orthovanadate and the parasite cells were then injected into the insect thorax, colonization of the salivary glands was greatly depressed for several days after blood feeding. Addition of P-Tyr ecto-phosphatase substrates such as p-nitrophenyl phosphate (pNPP) and P-Tyr inhibited the adhesion of T. rangeli to salivary glands, but P-Ser, P-Thr and beta-glycerophosphate were completely ineffective. Immunoassays using anti-P-Tyr-residues revealed a large number of P-Tyr-proteins in extracts of R. prolixus salivary glands, which could be potentially targeted by T. rangeli during adhesion. These results indicate that dephosphorylation of structural P-Tyr residues on the gland cell surfaces, mediated by a P-Tyr ecto-phosphatase of the parasite, is a key event in the interaction between T. rangeli and R. prolixus salivary glands. (C) 2012 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

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OBJECTIVE To determine the incidence of type IV prostatitis in patients with kidney transplantation receiving an immunosuppression regimen and to compare it with that of a nonimmunosuppressed control group. METHODS We retrospectively reviewed 216 electronic charts of patients who had undergone surgical treatment for benign prostatic hyperplasia from August 2000 to January 2006. Of the 216 patients, 183 did not receive immunosuppressive therapy and were included in the control group (group 1). The other 33 patients had undergone kidney transplantation and were included in the study group (group 2). The patient data were accessed for age at surgery, International Prostate Symptom Score, prostate volume, preoperative serum prostate-specific antigen level, history of acute urinary retention, and surgical approach (open vs transurethral resection of prostate). Histologic findings from the surgical specimens were also recorded. RESULTS The mean age at surgery, mean serum prostate-specific antigen level, mean prostate volume, and mean International Prostate Symptom Score were not significantly different between both groups. However, histologic evidence of chronic prostatitis was obtained in 145 surgical specimens (78%) from group 1 and in just 3 specimens from group 2 (9%; P < .001). Moreover, nonimmunosuppressed patients had a 38.2 times greater risk of presenting with prostatitis than did the immunosuppressed patients. CONCLUSION Imunnosuppresion therapy in kidney transplantation has a protective factor in the prostatitis incidence. UROLOGY 79: 662-664, 2012. (C) 2012 Elsevier Inc.

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Introduction: The aim of this prospective clinical study was to investigate the cephalometric changes produced by bonded spurs associated with high-pull chincup therapy in children with Angle Class I malocclusion and anterior open bite. Methods: Thirty patients with an initial mean age of 8.14 years and a mean anterior open bite of -3.93 mm were treated with bonded spurs associated with chincup therapy for 12 months. An untreated control group of 30 subjects with an initial mean age of 8.36 years and a mean anterior open bite of -3.93 mm and the same malocclusion was followed for 12 months for comparison. Student t tests were used for intergroup comparisons. Results: The treated group demonstrated a significantly greater decrease of the gonial angle, and increase in overbite, palatal tipping of the maxillary incisors, and vertical dentoalveolar development of the maxillary and mandibular incisors compared with the control group. Conclusions: The association of bonded spurs with high-pull chincup therapy was efficient for the correction of the open bite in 86.7% of the patients, with a 5.23-mm (SD, +/- 1.69) overbite increase. (Am J Orthod Dentofacial Orthop 2012;142:487-93)

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Aim: This study examines if injection of cobalt chloride (CoCl2) or antagonists of muscarinic cholinergic (atropine), mu(1)-opioid (naloxonazine) or 5-HT1 serotonergic (methiothepin) receptors into the dorsal or ventral portions of the anterior pretectal nucleus (APtN) alters the antinociceptive effects of stimulating the retrosplenial cortex (RSC) in rats. Main method: Changes in the nociceptive threshold were evaluated using the tail flick or incision pain tests in rats that were electrically stimulated at the RSC after the injection of saline, CoCl2 (1 mM, 0.10 mu L) or antagonists into the dorsal or ventral APtN. Key findings: The injection of CoCl2, naloxonazine (5 mu g/0.10 mu L) or methiothepin (3 mu g/0.10 mu L) into the dorsal APtN reduced the stimulation-produced antinociception from the RSC in the rat tail flick test. Reduction of incision pain was observed following stimulation of the RSC after the injection of the same substances into the ventral APtN. The injection of atropine (10 ng/0.10 mu L) or ketanserine (5 mu g/0.10 mu L) into the dorsal or ventral APtN was ineffective against the antinociception resulting from RSC stimulation. Significance: mu(1)-opioid- and 5-HT1-expressing neurons and cell processes in dorsal and ventral APtN are both implicated in the mediation of stimulation-produced antinociception from the RSC in the rat tail flick and incision pain tests, respectively. (c) 2012 Elsevier Inc. All rights reserved.

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The purpose of this study was to correlate the trochlear shape and patellar tilt angle and lateral patellar displacement at rest and maximal voluntary isometric contraction (MVIC) exercises during open (OKC) and closed kinetic chain (CKC) in subjects with and without anterior knee pain. Subjects were all women, 20 who were clinically healthy and 19 diagnosed with anterior knee pain. All subjects were evaluated and subjected to magnetic resonance exams during OKC and CKC exercise with the knee placed at 15, 30, and 45 degrees of flexion. The parameters evaluated were sulcus angle, patellar tilt angle and patellar displacement using bisect offset. Pearson's r coefficient was used, with p < .05. Our results revealed in knee pain group during CKC and OKC at 15 degrees that the increase in the sulcus angle is associated with a tilt increase and patellar lateral displacement. Comparing sulcus angle, patellar tilt angle and bisect offset values between MVIC in OKC and CKC in the knee pain group, it was observed that patellar tilt angle increased in OKC only with the knee flexed at 30 degrees. Based on our results, we conclude that reduced trochlear depth is correlated with increased lateral patellar tilt and displacement during OKC and CKC at 15 degrees of flexion in people with anterior knee pain. By contrast, 30 degrees of knee flexion in CKC is more recommended in rehabilitation protocols because the patella was more stable than in other positions.

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The main purposes of this manuscript are to provide an overview of various modalities of surgical correction of anterior plagiocephaly and to emphasize their differences with the classic open frontal-orbital advancement. Advancement of technology provides development of many other ways to achieve the same results. The authors describe the classic open frontal-orbital advancement and compare with other proposed techniques for correction of frontal plagiocephaly. The main limitation of the use of new forms of treatment of the anterior plagiocephaly is the age of the patient. There is still no consensus on criteria for quantitative evaluation of surgical results, and new forms of treatment do not present results with long follow-up. Frontal-orbital advancement is the preferred procedure to correct unicoronal synostosis due to its universal indication regardless of the age and degree of deformation of the anterior plagiocephaly.