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排序方式: 共有2047条查询结果,搜索用时 31 毫秒
41.
42.
Rebecca E. Conway Camilo Rojas Jesse Alt Zora Nováková Spencer M. Richardson Tori C. Rodrick Julio L. Fuentes Noah H. Richardson Jonathan Attalla Samantha Stewart Beshoy Fahmy Cyril Barinka Mallika Ghosh Linda H. Shapiro Barbara S. Slusher 《Angiogenesis》2016,19(4):487-500
Prostate-specific membrane antigen (PSMA) is a membrane-bound glutamate carboxypeptidase expressed in a number of tissues. PSMA participates in various biological functions depending on the substrate available in the particular tissue; in the brain, PSMA cleaves the abundant neuropeptide N-acetyl-aspartyl-glutamate to regulate release of key neurotransmitters, while intestinal PSMA cleaves polyglutamated peptides to supply dietary folate. PSMA expression is also progressively upregulated in prostate cancer where it correlates with tumor progression as well as in tumor vasculature, where it regulates angiogenesis. The previous research determined that PSMA cleavage of small peptides generated via matrix metalloprotease-mediated proteolysis of the extracellular matrix protein laminin potently activated endothelial cells, integrin signaling and angiogenesis, although the specific peptide substrates were not identified. Herein, using enzymatic analyses and LC/MS, we unequivocally demonstrate that several laminin-derived peptides containing carboxy-terminal glutamate moieties (LQE, IEE, LNE) are bona fide substrates for PSMA. Subsequently, the peptide products were tested for their effects on angiogenesis in various models. We report that LQ, the dipeptide product of PSMA cleavage of LQE, efficiently activates endothelial cells in vitro and enhances angiogenesis in vivo. Importantly, LQE is not cleaved by an inactive PSMA enzyme containing an active site mutation (E424S). Endothelial cell activation by LQ was dependent on integrin beta-1-induced activation of focal adhesion kinase. These results characterize a novel PSMA substrate, provide a functional rationale for the upregulation of PSMA in cancer cells and tumor vasculature and suggest that inhibition of PSMA could lead to the development of new angiogenic therapies. 相似文献
43.
Martínez-Borra J López-Larrea C González S Fuentes D Dieguez A Deschamps EM Pérez-Pariente JM López-Vázquez A de Francisco R Rodrigo L 《The American journal of gastroenterology》2002,97(9):2350-2356
OBJECTIVES: Infliximab, a chimeric monoclonal antibody directed against tumor necrosis factor-alpha (anti-TNF-alpha), has been effective in the treatment of patients with active Crohn's disease and with fistulas. We investigated the effect of infliximab on circulating cytokines and acute phase proteins in patients with fistulas to determine the clinical response to anti-TNF-alpha. METHODS: A total of 36 patients with fistulizing Crohn's disease were selected for study. Serum from patients was drawn before the infusion on day 0 and at wk 2, 4, 6, 8, and 10 after completion of treatment. Circulating concentrations of TNF-alpha, interleukin-1beta (IL-1beta), and IL-6 were measured by ELISA. The functional activity of circulating TNF-alpha was assessed by the WEHI 164 TNF-alpha bioassay. Acute phase proteins were also determined. RESULTS: Elevated TNF-alpha, IL-1beta, IL-6, and acute phase proteins were observed in patients with Crohn's disease. Of the patients with fistulas, 22 (61.1%) responded to treatment. Before receiving infliximab, higher levels of serum TNF-alpha were found in patients who did not respond to infliximab compared with those who did (median interquartile range 26, 0-245 pg/ml; n = 14 vs 0, 0-22 pg/ml, n = 22). Patients showed no change in circulating levels of TNF-alpha during the course of the study. CONCLUSIONS: This treatment produces a clinical improvement in about two-thirds of CD patients with fistulas. The circulating levels of TNF-alpha are associated with the response to infliximab and could help to identify patients who would benefit from anti-TNF-alpha treatment. 相似文献
44.
A Buendía Hernández J Vázquez J Fuentes F Attié J Ovseyevitz 《Archivos del Instituto de Cardiología de México》1987,57(3):207-211
Due to the frequent association of congenital heart disease and urinary tract malformations we studied 434 patients undergoing angiocardiograms for diagnosis of their congenital heart disease. In every patient a plain abdominal X-ray film was made in order to observe urinary elimination of the contrast material. We found 70 patients with urinary tract malformations, the most frequent of which was pyelo-chaliceal dilatation, accounting for 47.1% of all the malformations found. A double pyelo-chaliceal system was found in 25.7%, kidney hypoplasia in 10% and in lower frequencies double urethers, kidney agenesia, pelvic kidneys, horseshoe-shaped kidney and others. Patients were usually urologically asymptomatic. In view of the frequent association of congenital heart disease and urinary tract malformations a plain abdominal X-ray film should always be performed postangiographically. In some cases a contrast urography is recommended. 相似文献
45.
Maria Isabel Hombrados‐Mendieta Luis Gomez‐Jacinto Juan Manuel Dominguez‐Fuentes Patricia Garcia‐Leiva 《Journal of community psychology》2013,41(5):601-614
The aim of this study was to analyze the influence of the sense of community (SOC) on satisfaction with life (SWL) in native and immigrant populations in Spain. The main hypothesis was that SOC would moderate the negative effects associated with the immigrant adaptation process. It was further hypothesized that there would be no differences in SWL between immigrants with a high SOC and the native population. The study included 1,646 participants living in Malaga (Spain), comprising 946 natives and 700 immigrants. Data were collected using random route sampling and survey methodology. The results showed that people with higher SOC had significantly greater SWL. It was also found that SWL was greater in natives than in immigrants when the level of SOC was low or medium. However, when SOC was high there were no significant differences between the groups in SWL. The data support the hypothesis that SOC acts as a moderating variable that buffers the effect of the adaptation process experienced by immigrants. 相似文献
46.
Crutel Véronique Lambert Estelle Penelaud Pierre-François Albarrán Severo Cristina Fuentes Joaquin Rosier Antoine Hervás Amaia Marret Stéphane Oliveira Guiomar Parellada Mara Kyaga Simon Gouttefangeas Sylvie Bertrand Marianne Ravel Denis Falissard Bruno 《Journal of autism and developmental disorders》2021,51(8):2973-2973
Journal of Autism and Developmental Disorders - The author of the article would like to add a video abstract as a supplementary material for a published article. The supplementary file is published... 相似文献
47.
B. Fuentes S. Amaro M. Alonso de Leciñana J.F. Arenillas O. Ayo-Martín M. Castellanos M. Freijo A. García-Pastor M. Gomis M. Gómez Choco E. López-Cancio P. Martínez Sánchez A. Morales E.J. Palacio-Portilla M. Rodríguez-Yáñez J. Roquer T. Segura J. Serena J. Vivancos-Mora 《Neurología (Barcelona, Spain)》2021,36(4):305-323
ObjectiveTo update the Spanish Society of Neurology's guidelines for stroke prevention in patients with type 2 diabetes or prediabetes, analysing the available evidence on the effect of metabolic control and the potential benefit of antidiabetic drugs with known vascular benefits in addition to conventional antidiabetic treatments in stroke prevention.DevelopmentPICO-type questions (Patient, Intervention, Comparison, Outcome) were developed to identify practical issues in the management of stroke patients and to establish specific recommendations for each of them. Subsequently, we conducted systematic reviews of the PubMed database and selected those randomised clinical trials evaluating stroke as an independent variable (primary or secondary). Finally, for each of the PICO questions we developed a meta-analysis to support the final recommendations.ConclusionsWhile there is no evidence that metabolic control reduces the risk of stroke, some families of antidiabetic drugs with vascular benefits have been shown to reduce these effects when added to conventional treatments, both in the field of primary prevention in patients presenting type 2 diabetes and high vascular risk or established atherosclerosis (GLP-1 agonists) and in secondary stroke prevention in patients with type 2 diabetes or prediabetes (pioglitazone). 相似文献
48.
José Fernando Val-Bernal Ainara Azueta Luis Antonio Ortiz-Rivas Javier Fuentes Roberto Ballestero 《Pathology, research and practice》2013
Hibernomas are uncommon benign lipomatous tumors which show differentiation toward brown fat. To our knowledge, only one case of adrenal hibernoma has been previously reported. We describe a 55-year-old woman showing an incidental, 1.7 cm-hibernoma associated with a 2.6 cm-cortical adenoma producing primary hyperaldosteronism (Conn's syndrome), both in the left adrenal gland. The hibernoma was composed predominantly of univacuolated mature fat cells admixed with small vessels. Scattered areas composed of large multivacuolated pale cells with central or paracentral nuclei, mimicking lipoblasts, accounting for less than 30% of the tumor, were found. These cells lacked nuclear hyperchromasia or marked atypia, were S100-positive, and showed numerous mitochondria reactive with the anti-mitochondrial antibody. A diagnosis of lipoma-like hibernoma was made. Pathologists should be aware of this variant of hibernoma to avoid misdiagnosis and excessive treatment. 相似文献
49.
Eric Parmentier Erica Marucco Fuentes Morgane Millot Xavier Raick Marc Thiry 《Journal of anatomy》2021,238(4):956-969
The ability to produce sounds has been reported in various Ostraciidae but not deeply studied. In some Ostracion species, two different sound-producing muscles allow these boxfishes to produce two different kinds of sounds in a sequence. This study investigates sound production in another Indo-Pacific species, the longhorn cowfish Lactoria cornuta that also possesses two pairs of sonic muscles associated with the swim bladder: extrinsic sonic muscles (ESMs) and intrinsic sonic muscles (ISMs). The cowfish produces two kinds of sounds called hums and clicks. Hums are made of trains of low amplitude pulses that last for long periods of time, suggesting that they are produced by fatigue-resistant muscles, whereas clicks correspond to shorter sounds with greater amplitude than the hums, suggesting that they result from more powerful contractions. Ultra-structural differences are found between extrinsic and intrinsic sonic muscles. According to features such as long sarcomeres, long I-bands, a high number of mitochondria, and a proliferation of sarcoplasmic reticulum (SR), ESMs would be able to produce fast, strong, and short contractions corresponding to clicks (the shortest sounds with the greatest amplitude). ISMs have the thinnest cells, the smallest number of myofilaments that have long I-bands, the highest volume of mitochondria, and well-developed SR supporting these muscles; these features should generate fast and prolonged contractions that could correspond to the hums that can be produced over long periods of time. A concluding figure shows clear comparisons of the different fibers that were studied in L. cornuta. This study also compared the call features of each sound with the cowfish's hearing ability and supports L. cornuta was more sensitive to frequencies ranging between at least 100 and 400 Hz with thresholds of 128–143 dB re 1 µPa over this range, meaning that they are sensitive to the frequencies produced by conspecifics. 相似文献
50.
Devon L. Drey Eric C. O'Quinn Tamilarasan Subramani Kristina Lilova Gianguido Baldinozzi Igor M. Gussev Antonio F. Fuentes Joerg C. Neuefeind Michelle Everett David Sprouster Alexandra Navrotsky Rodney C. Ewing Maik Lang 《RSC advances》2020,10(57):34632
Pyrochlore (A2B2O7) is an important, isometric structure-type because of its large variety of compositions and structural derivatives that are generally related to different disordering mechanisms at various spatial scales. The disordering is key to understanding variations in properties, such as magnetic behavior or ionic conduction. Neutron and X-ray total scattering methods were used to investigate the degree of structural disorder in the Ho2Ti2−xZrxO7 (x = 0.0–2.0, Δx = 0.25) solid solution series as a function of the Zr-content, x. Ordered pyrochlores (Fdm) disorder to defect fluorite (Fmm) via cation and anion disordering. Total scattering experiments with sensitivity to the cation and anion sublattices provide unique insight into the underlying atomic processes. Using simultaneous Rietveld refinement (long-range structure) and small-box refinement PDF analysis (short-range structure), we show that the series undergoes a rapid transformation from pyrochlore to defect fluorite at x ≈ 1.2, while the short-range structure exhibits a linear increase in a local weberite-type phase, C2221, over the entire composition range. Enthalpies of formation from the oxides determined using high temperature oxide melt solution calorimetry support the structural data and provide insight into the effect of local ordering on the energetics of disorder. The measured enthalpies of mixing are negative and are fit by a regular solution parameter of W = −31.8 ± 3.7 kJ mol−1. However, the extensive short-range ordering determined from the structural analysis strongly suggests that the entropies of mixing must be far less positive than implied by the random mixing of a regular solution. We propose a local disordering scheme involving the pyrochlore 48f to 8a site oxygen Frenkel defect that creates 7-coordinated Zr sites contained within local weberite-type coherent nanodomains. Thus, the solid solution is best described as a mixture of two phases, with the weberite-type nanodomains triggering the long-range structural transformation to defect fluorite after accumulation above a critical concentration (50% Ti replaced by Zr).Combined neutron and X-ray total scattering with calorimetric measurements of the solid solution series Ho2Ti2−xZrxO7 reveals a complex order–disorder transition across short, intermediate, and long length scales induced by chemical substitution. 相似文献