982 resultados para Endocrine Glands


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This review stresses the importance of studies that will provide a basic understanding of the pathology of parasite-infected vector insects. This knowledge should be a vital component of the very focussed initiatives currently being funded in the areas of vector control. Vector fecundity reduction is discussed as an example of such pathology. Underlying mechanisms are being investigated in a model system, Hymenolepis diminuta-infected Tenebrio molitor and in Onchocerca-infected blackflies and Plasmodium-infected Anopheles stephensi. In all cases, host vitellogenesis is disrupted by the parasite and, in the tapeworm/beetle model, interaction between the parasite and the endocrine control of the insect's reproductive physiology has been demonstrated.

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CONTEXT: The high diagnostic performance of plasma-free metanephrines (metanephrine and normetanephrine) (MN) for pheochromocytoma (PHEO) results from the tumoral expression of catechol-O-methyltransferase (COMT), the enzyme involved in O-methylation of catecholamines (CAT). Intriguingly, metanephrine, in contrast to epinephrine, is not remarkably secreted during a stress in hypertensive or normotensive subjects, whereas in PHEO patients CAT and MN are both raised to high levels. Because epinephrine and metanephrine are almost exclusively produced by the adrenal medulla, this suggests distinct CAT metabolism in chromaffin cells and pheochromocytes. OBJECTIVE: The objective of the study was to compare CAT metabolism between adrenal medulla and PHEO tissue regarding related enzyme expression including monoamine oxidases (MAO) and COMT. DESIGN: A multicenter comparative study was conducted. STUDY PARTICIPANTS: The study included 21 patients with a histologically confirmed PHEO and eight adrenal glands as control. MAIN OUTCOME MEASURES: CAT, dihydroxyphenol-glycol, 3,4-dihydroxyphenylacetic acid, and MN were measured in adrenal medulla and PHEO tissue. Western blot, quantitative RT-PCR and immunofluorescence studies for MAOA, MAOB, tyrosine hydroxylase, dopamine β-hydroxylase, L-amino acid decarboxylase, and COMT were applied on tissue homogenates and cell preparations. RESULTS: At both the protein and mRNA levels, MAOA and COMT are detected less often in PHEO compared with adrenal medulla, conversely to tyrosine hydroxylase, L-amino acid decarboxylase, and dopamine β-hydroxylase, much more expressed in tumor tissue. MAOB protein is detected less often in tumor but not differently expressed at the mRNA level. Dihydroxyphenol-glycol is virtually absent from tumor, whereas MN, produced by COMT, rises to 4.6-fold compared with adrenal medulla tissue. MAOA down-regulation was observed in 100% of tumors studied, irrespectively of genetic alteration identified; on the other hand, MAOA was strongly expressed in all adrenal medulla collected independently of age, gender, or late sympathetic activation of the deceased donor. CONCLUSION: High concentrations of MN in tumor do not only arise from CAT overproduction but also from low MAOA expression, resulting in higher substrate availability for COMT.

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The 2009 International Society of Urological Pathology Consensus Conference in Boston, made recommendations regarding the standardization of pathology reporting of radical prostatectomy specimens. Issues relating to surgical margin assessment were coordinated by working group 5. Pathologists agreed that tumor extending close to the 'capsular' margin, yet not to it, should be reported as a negative margin, and that locations of positive margins should be indicated as either posterior, posterolateral, lateral, anterior at the prostatic apex, mid-prostate or base. Other items of consensus included specifying the extent of any positive margin as millimeters of involvement; tumor in skeletal muscle at the apical perpendicular margin section, in the absence of accompanying benign glands, to be considered organ confined; and that proximal and distal margins be uniformly referred to as bladder neck and prostatic apex, respectively. Grading of tumor at positive margins was to be left to the discretion of the reporting pathologists. There was no consensus as to how the surgical margin should be regarded when tumor is present at the inked edge of the tissue, in the absence of transected benign glands at the apical margin. Pathologists also did not achieve agreement on the reporting approach to benign prostatic glands at an inked surgical margin in which no carcinoma is present.

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OBJECTIVE: To assess the feasibility and efficacy of subcutaneous amifostine therapy in patients with head and neck cancer treated with curative accelerated radiotherapy (RT). DESIGN: Retrospective study. SETTING: University of Lausanne, Lausanne, Switzerland. PATIENTS: Thirty-three consecutive patients (male-female ratio, 4.5; median age, 54 years [age range, 39-76 years]). INTERVENTIONS: Between November 2000 and January 2003, the 33 patients were treated with curative definitive (n = 19) or postoperative (n = 14) RT with (n = 26) or without (n = 7) chemotherapy. All patients received conformal RT. Fractionation schedule consisted of concomitant-boost (Friday afternoon session) accelerated RT using 70 Gy (2 Gy per fraction) in 6 weeks in patients treated with definitive RT and 66 Gy (2 Gy per fraction) in 5 weeks and 3 days in the postoperative setting. Parotid glands received at least 50 Gy in all patients. Amifostine was administered to a total dose of 500 mg subcutaneously, 15 to 30 minutes before morning RT sessions. RESULTS: All patients received their planned treatment (including chemotherapy). Ten patients received the full schedule of amifostine (at least 25 injections), 9 received 20 to 24 doses, 4 received 10 to 19 doses, 5 received 5 to 9 doses, and 5 received fewer than 5 doses. Fifteen patients (45%) did not show any intolerance related to amifostine use. Amifostine therapy was discontinued because of nausea in 11 patients (33%) and hypotension in 6 patients (18%), and 1 patient refused treatment. No grade 3, amifostine-related, cutaneous toxic effects were observed. Radiotherapy-induced grade 3 acute toxic effects included mucositis in 14 patients (42%), erythema in 14 patients (42%), and dysphagia in 13 patients (39%). Late toxic effects included grade 2 or more xerostomia in 17 patients (51%) and fibrosis in 3 patients (9%). Grade 2 or more xerostomia was observed in 8 (42%) of 19 patients receiving 20 injections or more vs 9 (64%) of 14 patients receiving fewer than 20 injections (P = .15). CONCLUSIONS: Subcutaneous amifostine administration in combination with accelerated concomitant-boost RT with or without chemotherapy is feasible. The major adverse effect of subcutaneous administration was nausea despite prophylactic antiemetic medication, and hypotension was observed in only 6 patients (18%).

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Notocotylus breviserialis has been collected from Anas bahamenis L. and Amazonetta brasiliensis (Gmelin), in Maricá, state of Rio de Janeiro, Brazil. It is the first time that this digenean is collected as adult in its natural hosts, and this is its first record for the neotropical region. The prevalence of N. breviserialis was 5.56% and 18.18% in A. bahamensis and in A. brasiliensis, respectively. New morphological data about the location of the vitelline glands and previtellinic space measurements are presented.

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La síndrome metabòlica s’associa amb un risc elevat de desenvolupar diabetis tipus 2 i malaltia cardiovascular. La síndrome metabòlica es defineix com un clúster d’anormalitats metabòliques i, d’entre totes, l’obesitat abdominal constitueix el factor de risc més prevalent i crític en el desenvolupament de la síndrome metabòlica, el risc cardiovascular augmentat i la resistència a la insulina. La prevalença augmentada de l’obesitat en la població a nivell mundial ha portat el teixit adipós al primer pla dels estudis epidemiològics. Anteriorment es considerava el reservori energètic de l’organisme, actualment es parla del teixit adipós com un òrgan endocrí, metabòlicament molt actiu, implicat en diferents vies i processos metabòlics. L’etiologia de l’obesitat és complexa i multifactorial, però es fa evident en la disfuncionalitat del teixit adipós. Un teixit adipós disfuncional veu superada la seva capacitat d’emmagatzemar lípid i respon amb la hipersecreció de diferents molècules (adipoquines, citoquines i mediadors inflamatoris) a favor de la resistència a la insulina, proinflamatòries i proaterogèniques. La fatty acid-binding protein 4 (FABP4) i la retinol-binding protein 4 (RBP4) són dues adipoquines que en circulació, es desconeix la funció exacta que duen a terme. Estudis recents han suggerit la FABP4 com a marcador d’adipositat, síndrome metabòlica i diabetis tipus 2. I, RBP4, malgrat que les dades de diferents estudis en humans desperten certa controvèrsia, s’ha associat amb la resistència a la insulina i el desenvolupament de la diabetis tipus 2. En aquesta memòria es recullen els treballs en què es va estudiar el paper d’aquestes adipoquines en relació a malalties de base metabòlica amb afectació del teixit adipós com són la síndrome metabòlica, la diabetis tipus 2, la hiperlipèmia familiar combinada i la, lipodistrofia associada a tractament combinat antiretroviral de la infecció pel virus de la immunodeficiència humana (VIH).