994 resultados para D-endocrine System


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The development of normal and abnormal glandular structures in the prostate is controlled at the endocrine and paracrine levels by reciprocal interactions between epithelium and stroma. To study these processes it is useful to have an efficient method of tissue acquisition for reproducible isolation of cells from defined histologies. Here we assessed the utility of a standardized system for acquisition and growth of prostatic cells from different regions of the prostate with different pathologies, and we compared the abilities of stromal cells from normal peripheral zone (PZ-S), benign prostatic hyperplasia (BPH-S), and cancer (CA-S) to induce the growth of a human prostatic epithelial cell line (BPH-1) in vivo. Using the tissue recombination method, we showed that grafting stromal cells (from any histology) alone, or BPH-1 epithelial cells alone produced no visible grafts. Recombining PZ-S with BPH-1 cells also produced no visible grafts (n = 15). Recombining BPH-S with BPH-1 cells generated small, well-organized and sharply demarcated grafts approximately 3-4 mm in diameter (n = 9), demonstrating a moderate inductive ability of BPH-S. Recombining CA-S with BPH-1 cells generated highly disorganized grafts that completely surrounded the host kidney and invaded into adjacent renal tissue, demonstrating induction of an aggressive phenotype. We conclude that acquisition of tissue from toluidine blue dye stained specimens is an efficient method to generate high quality epithelial and/or stromal cultures. Stromal cells derived by this method from areas of BPH and cancer induce epithelial cell growth in vivo which mimics the natural history of these diseases.

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The urocortin (UCN)-like immunoreactivity and UCN mRNA distribution in various regions of the nonprimate mammalian brain have been reported. However, the Edinger-Westphal nucleus (EW) appears to be the only brain site where UCN expression is conserved across species. Although UCN peptides are present throughout vertebrate phylogeny, the functional roles of both UCN and EW remain poorly understood. Therefore, a study focused on UCN system organization in the primate brain is warranted. By using immunohistochemistry (single and double labeling) and in situ hybridization, we have characterized the organization of UCN-expressing cells and fibers in the central nervous system and pituitary of the capuchin monkey (Cebus apella). In addition, the sequence of the prepro-UCN was determined to establish the level of structural conservation relative to the human sequence. To understand the relationship of acetylcholine cells in the EW, a colocalization study comparing choline acetyltransferase (ChAT) and UCN was also performed. The cloned monkey prepro-UCN is 95% identical to the human preprohormone across the matched sequences. By using an antiserum raised against rat UCN and a probe generated from human cDNA, we found that the EW is the dominant site for UCN expression, although UCN mRNA is also expressed in spinal cord lamina IX. Labeled axons and terminals were distributed diffusely throughout many brain regions and along the length of the spinal cord. of particular interest were UCN-immunoreactive inputs to the medial preoptic area, the paraventricular nucleus of the hypothalamus, the oral part of the spinal trigeminal nucleus, the flocculus of the cerebellum, and the spinal cord laminae VII and X. We found no UCN hybridization signal in the pituitary. In addition, we observed no colocalization between ChAT and UCN in EW neurons. Our results support the hypothesis that the UCN system might participate in the control of autonomic, endocrine, and sensorimotor functions in primates.

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In the network reconfiguration context, the challenge nowadays is to improve the system in order to get intelligent systems that are able to monitor the network and produce refined information to support the operator decisions in real time, this because the network is wide, ramified and in some places difficult to access. The objective of this paper is to present the first results of the network reconfiguration algorithm that has been developed to CEMIG-D. The algorithm's main idea is to provide a new network configuration, after an event (fault or study case), based on an initial condition and aiming to minimize the affected load, considering the restrictions of load flow equations, maximum capacity of the lines as well as equipments and substations, voltage limits and system radial operation. Initial tests were made considering real data from the system, provided by CEMIG-D and it reveals very promising results. © 2013 IEEE.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Compared with other mature engineering disciplines, fracture mechanics of concrete is still a developing field and very important for structures like bridges subject to dynamic loading. An historical point of view of what done in the field is provided and then the project is presented. The project presents an application of the Digital Image Correlation (DIC) technique for the detection of cracks at the surface of concrete prisms (500mmx100mmx100mm) subject to flexural loading conditions (Four Point Bending test). The technique provide displacement measurements of the region of interest and from this displacement field information about crack mouth opening (CMOD) are obtained and related to the applied load. The evolution of the fracture process is shown through graphs and graphical maps of the displacement at some step of the loading process. The study shows that it is possible with the DIC system to detect the appearance and evolution of cracks, even before the cracks become visually detectable.

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Endocrine disruption, in particular disruption by estrogen-active compounds, has been identified as an important ecotoxicological hazard in the aquatic environment. Research on the impact of endocrine disrupting compounds (EDCs) on wildlife has focused on disturbances of the reproductive system. However, there is increasing evidence that EDCs affect a variety of physiological systems other than the reproductive system. Here, we discuss if EDCs may be able to affect the immune system of fish, as this would have direct implications for individual fitness and population growth. Evidence suggesting an immunomodulatory role of estrogens in fish comes from the following findings: (a) estrogen receptors are expressed in piscine immune organs, (b) immune gene expression is modulated by estrogen exposure, and (c) pathogen susceptibility of fish increases under estrogen exposure.

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Criteria for the staging and grading of neuroendocrine tumors (NETs) of midgut and hindgut origin were established at the second Consensus Conference in Frascati (Rome) organized by the European Neuroendocrine Tumor Society (ENETS). The proposed tumor-node-metastasis (TNM) classifications are based on the recently published ENETS Guidelines for the Diagnosis and Treatment of gastroenteropancreatic NETs and follow our previous proposal for foregut tumors. The new TNM classifications for NETs of the ileum, appendix, colon, and rectum, and the grading system were designed, discussed, and consensually approved by all conference participants. These proposals need to be validated and are meant to help clinicians in the stratification, treatment and follow-up of patients.

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PURPOSE: To evaluate the expression and presence of surfactant protein (SP) A and SP-D in the lacrimal apparatus, at the ocular surface, and in tears in healthy and pathologic states. METHODS: Expression of mRNA for SP-A and SP-D was analyzed by RT-PCR in healthy lacrimal gland, conjunctiva, cornea, and nasolacrimal ducts as well as in a spontaneously immortalized conjunctival epithelial cell line (HCjE; IOBA-NHC) and a SV40-transfected cornea epithelial cell line (HCE). Deposition of SP-A and SP-D was determined by Western blot, dot blot, and immunohistochemistry in healthy tissues, in tears, aqueous humor, and in sections of different corneal abnormalities (keratoconus, herpetic keratitis, and Staphylococcus aureus-based ulceration). Cell lines were stimulated with different cytokines and bacterial components and were analyzed for the production of SP-A and SP-D by immunohistochemistry. RESULTS: The presence of SP-A and SP-D on mRNA and protein levels was evidenced in healthy lacrimal gland, conjunctiva, cornea, and nasolacrimal duct samples. Moreover, both proteins were present in tears but were absent in aqueous humor. Immunohistochemistry revealed the production of both peptides by acinar epithelial cells of the lacrimal gland and epithelial cells of the conjunctiva and nasolacrimal ducts, whereas goblet cells revealed no reactivity. Healthy cornea revealed weak reactivity on epithelial surface cells only. In contrast, SP-A and SP-D revealed strong reactivity in patients with herpetic keratitis and corneal ulceration surrounding lesions and in several immigrated defense cells. Reactivity in corneal epithelium and endothelium was also seen in patients with keratoconus. Cell culture experiments revealed that SP-A and SP-D are produced by both epithelial cell lines without and after stimulation with cytokines and bacterial components. CONCLUSIONS: These results show that SP-A, in addition to SP-D, is a peptide of the tear film. Based on the known direct and indirect antimicrobial effects of collectins, the surfactant-associated proteins A and D seem to be involved in several ocular surface diseases.

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CONTEXT: The success of pancreatic islet transplantation depends largely on the capacity of the islet graft to survive the initial phase immediately after transplantation until revascularization is completed. Endothelin-1 (ET-1) is a strong vasoconstrictor which has been involved in solid organ graft failure but is also known to be a potent mitogenic/anti-apoptotic factor which could also potentially enhance the survival of the transplanted islets. OBJECTIVE: Characterization of the endothelin system with regard to a potential endothelin agonist/antagonist treatment. DESIGN: Regulated expression of the endothelin system in human and rat pancreatic islets and beta-cell lines was assessed by means of immunohistochemistry, competition binding studies, western blot, RT-PCR, real-time PCR and transplant studies. RESULTS: ET-1, ETA- and ETB-receptor immunoreactivity was identified in the endocrine cells of human and rat pancreatic islets. The corresponding mRNA was detectable in rat beta-cell lines and isolated rat and human pancreatic islets. Competition binding studies on rat islets revealed binding sites for both receptor types. ET-1 stimulated the phosphorylation of mitogen-activated protein kinase, which was prevented by ETA- and ETB-receptor antagonists. After exposure to hypoxia equal to post-transplant environment oxygen tension, mRNA levels of ET-1 and ETB-receptor of human islets were robustly induced whereas ETA-receptor mRNA did not show significant changes. Immunostaining signals for ET-1 and ETA-receptor of transplanted rat islets were markedly decreased when compared to native pancreatic sections. CONCLUSIONS: In pancreatic islets, ET-1 and its receptors are differentially expressed by hypoxia and after transplantation. Our results provide the biological basis for the study of the potential use of endothelin agonists/antagonists to improve islet transplantation outcome.

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This paper presents a system for 3-D reconstruction of a patient-specific surface model from calibrated X-ray images. Our system requires two X-ray images of a patient with one acquired from the anterior-posterior direction and the other from the axial direction. A custom-designed cage is utilized in our system to calibrate both images. Starting from bone contours that are interactively identified from the X-ray images, our system constructs a patient-specific surface model of the proximal femur based on a statistical model based 2D/3D reconstruction algorithm. In this paper, we present the design and validation of the system with 25 bones. An average reconstruction error of 0.95 mm was observed.