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81.
Sensory and inflammatory colonic changes induced by vincristine in distinct rat models of colitis 下载免费PDF全文
M. T. B. Silva A. A. Peixoto‐Junior L. S. Marinho N. S. Matias P. M. G. Soares A. A. Santos G. A. C. Brito F. H. Rola F. de A. A. Gondim 《Autonomic & autacoid pharmacology》2015,34(3-4):27-34
Preclinical and clinical studies show that gastrointestinal (GI) inflammation can evoke sensory changes occasionally far from the original inflammatory site. Animal models of colitis with either trinitrobenzenesulphonic acid (TNBS) or mustard oil (MO) produce distinct patterns of somatic and visceral sensory changes. We evaluated the effects of four doses of i.v. vincristine 150 μg kg?1 (total of 600 μg kg?1) treatment on the somatic (thermal nociceptive threshold) and colonic (morphological) changes induced by TNBS or MO in rats. TNBS and MO groups were further submitted to vincristine or saline pretreatments. TNBS induced somatic hypersensitivity, while MO induced somatic hyposensitivity (P < 0.05) when compared to the saline and ethanol control groups. Vincristine per se induced somatic hypersensitivity (P < 0.05). This effect was enhanced by TNBS and reversed by MO treatments. Although vincristine increased the colitis area (colonic weight length?1 ratio) and the Morris' score in TNBS‐treated rats, it did not alter the colitis area and even lowered the Morris' score in MO‐treated rats. Compared to the saline (control) group, vincristine did not alter the colonic microscopic pattern. However, such lesions scores are higher (P < 0.05) in colitis groups induced by TNBS and MO, pretreated or not with vincristine. In conclusion, the somatic changes induced by different models of experimental colitis are diverse and modulated differently by vincristine. 相似文献
82.
Soares Rogerio N. Ramirez-Perez Francisco I. Cabral-Amador Francisco J. Morales-Quinones Mariana Foote Christopher A. Ghiarone Thaysa Sharma Neekun Power Gavin Smith James A. Rector R. Scott Martinez-Lemus Luis A. Padilla Jaume Manrique-Acevedo Camila 《Age (Dordrecht, Netherlands)》2022,44(3):1657-1675
GeroScience - Aging of the vasculature is characterized by endothelial dysfunction and arterial stiffening, two key events in the pathogenesis of cardiovascular disease (CVD). Treatment with sodium... 相似文献
83.
Luduvico Karina Pereira Spohr Luiza de Aguiar Mayara Sandrielly Soares Teixeira Fernanda Cardoso Bona Natália Pontes de Mello Julia Eisenhardt Spanevello Roselia Maria Stefanello Francieli Moro 《Metabolic brain disease》2022,37(6):2133-2140
Metabolic Brain Disease - Acetylcholine is an excitatory neurotransmitter that modulates synaptic plasticity and communication, and it is essential for learning and memory processes. This... 相似文献
84.
Emy Hiura Aline del Carmen Garcia Lopes Jeanne Saraiva da Paz Maylla Garschagen Gava Mayra Cunha Flecher Manuela Colares Filippe Elias de Freitas Soares Leandro Abreu da Fonseca Tracy Lacerda Jackson Victor de Araújo Fabio Ribeiro Braga 《Parasitology research》2015,114(9):3301-3308
The objective of this study was to evaluate the infectivity of Toxocara canis eggs after interacting with isolated nematophagous fungi of the species Duddingtonia flagrans (AC001) and Pochonia chlamydosporia (VC4), and test the predatory activity of the isolated AC001 on T. canis second stage larvae after 7 days of interaction. In assay A, 5000 embryonated T. canis eggs previously in contact with the AC001 and VC4 isolated for 10 days were inoculated into domestic chickens (Gallus gallus domesticus), and then these animals were necropsied to collect material (digested liver, intestine, muscles and lungs) at 3-, 7-, 14-, and 21-day intervals after inoculation. In assay A, the results demonstrated that the prior interaction of the eggs with isolated AC001 and VC4 decreases the amount of larvae found in the collected organs. Difference (p?<?0.01) was observed in the medium larvae counts recovered from liver, lung, intestine, and muscle of animals in the treated groups when compared to the animals in the control group. At the end of assay A, a percentage reduction of 87.1 % (AC001) and 84.5 % (VC4) respectively was recorded. In the result of assay B, the isolated AC001 showed differences (p?<?0.01) compared to the control group, with a reduction of 53.4 % in the recovery of L2. Through these results, it is justified to mention that prior interaction of embryonated T. canis eggs with the tested fungal isolates were efficient in reducing the development and migration of this parasite, in addition to the first report of proven predatory activity on L2. 相似文献
85.
Mathematical Modeling of Crystallization Elution Fractionation of Ethylene/1‐Octene Copolymers 下载免费PDF全文
Nuttawat Chokputtanawuttilerd Siripon Anantawaraskul Nantiya Inwong João B. P. Soares 《Macromolecular chemistry and physics.》2015,216(6):621-635
Crystallization elution fractionation (CEF) is a relatively new polyolefin characterization technique used to estimate the chemical composition distribution (CCD) of semicrystalline copolymers. CEF is developed to enhance the resolution and reduce the analysis time of temperature rising elution fractionation (TREF) by separating polymer samples in both the crystallization and elution steps. A model based on the concept of population balance, crystallization/dissolution kinetics, and dispersion model is developed to understand the CEF fractionation mechanisms. The proposed CEF model is found to describe well the experimental CEF profiles of a series of ethylene/1‐octene copolymers with different comonomer contents.
86.
Dr. António E. Pinto M.D. Paula Chaves M.D. Paulo Fidalgo M.D. António G. Oliveira M.D. Ph.D. Carlos N. LeitÃo M.D. Ph.D. Jorge Soares M.D. Ph.D. 《Diseases of the colon and rectum》1997,40(4):411-419
BACKGROUND: The clinical behavior of colorectal carcinoma is highly variable without reliable predictive biomarkers. Previous reports have shown that flow cytometric DNA analysis may provide valuable prognostic information in these tumors. PURPOSE AND METHODS: This study evaluates the DNA ploidy and the S-phase fraction (SPF) on frozen samples obtained from 61 patients with colorectal carcinoma by using flow cytometry, and it correlates the data with histopathologic features known to affect disease prognosis. Tumors were classified using the World Health Organization's histologic criteria and were staged according the American Joint Committee on Cancer's classification system. Grade of the neoplasm, vascular invasion, and perineural tumor spread were evaluated in every case. RESULTS: Fifty-nine percent of tumors were aneuploid and showed statistically significant higher S-phase values than diploid tumors (22.5 vs. 11.2 percent; P < 0.00001). Mean SPF of the whole series was 17.9 (range, 4.2–44.2) percent. A statistically significant association was found between SPF values and histologic grade (P < 0.0016), nodal status (P <0.0007), distant metastasis(P < 0.0001), tumor stage (P <0.0001), venous invasion (P < 0.0002), and lymphatic permeation (P < 0.01) but not with perineural growth and infiltration of the neoplasm through the bowel wall (T). DNA ploidy correlated positively with tumor stage (P <0.03), and the association between aneuploidy and advanced stages of the disease was statistically significant. CONCLUSIONS: These findings showed that flow cytometric DNA ploidy and SPF, evaluated in fresh samples, are potentially useful parameters to estimate colorectal carcinoma biopathology. Aneuploidy and high replicative neoplastic activity correlated with histopathologic features that are commonly associated with the prognosis of colorectal carcinoma, being SPF-related to disease dissemination and, therefore, an indicator of clinical relevance. 相似文献
87.
The male mongoose is a seasonal breeder and displays a distinct seasonal pattern in serum androgen levels. In this series of experiments testicular responsiveness to luteinizing hormone (LH) was evaluated during the breeding (active) and inactive seasons. The responsiveness of testes to LH was assessed by measuring [125I]hCG (human chorionic gonadotropin) binding to dispersed interstitial cells and by measuring in vitro LH-stimulated androgen release by dispersed interstitial cells. The binding data indicated that there was a significantly greater concentration of binding sites/Leydig cell during the active season than during the inactive season. In contrast, dispersed interstitial cells prepared from animals trapped during the active and inactive seasons were equally responsive to small doses (“physiological”) of ovine LH (oLH); however, higher doses of oLH produced a significant depression in the interstitial cell output of androgen during the inactive season but not during the active season. These results indicate that there are seasonal differences in the responses of the testis to LH. Whether the seasonal pattern of serum androgen levels in the male mongoose is directed by seasonal changes in serum gonadotropin levels or changes in testicular responsiveness to LH is discussed. 相似文献
88.
89.
Raquel Costa‐Almeida Raquel Soares Pedro L. Granja 《Journal of tissue engineering and regenerative medicine》2018,12(1):240-251
Fibroblasts constitute a dynamic and versatile population of cells of mesenchymal origin, implicated in both regenerative strategies and pathological conditions. Despite being frequently associated to disease development, particularly through the establishment of fibrotic tissue, fibroblasts hold great potential for tissue engineering and regenerative medicine applications. They are responsible for synthesizing and depositing extracellular matrix components, allowing other cells to settle and migrate along a three‐dimensional support and thereby generating an organ‐specific architecture. Additionally, they produce bioactive molecules that are involved in several physiological processes, including angiogenesis and tissue repair. Although there seems to be much still to unveil about these fascinating cells they have been attracting increasing interest and are now being intensively explored as a cell source to develop bioengineered tissue constructs or to improve stem cell‐based technologies. This review intends to highlight the potential of fibroblasts in orchestrating tissue regeneration, as well as to contribute to uncover uncharted prospective applications of these cells. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
90.
Indiara Soares Oliveira Leonardo Oliveira Pena Costa Alessandra Narciso Garcia Gisela Cristiane Miyamoto Cristina Maria Nunes Cabral Lucíola da Cunha Menezes Costa 《Revista brasileira de fisioterapia (S?o Carlos (S?o Paulo, Brazil))》2018,22(4):328-335