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81.
Currently, glaucoma is recognised as an optic neuropathy. Selective death of retinal ganglion cells (RGC) is the hallmark of glaucoma, which is also associated with structural changes in the optic nerve head. The process of RGC death is thought to be biphasic: a primary injury responsible for initiation of damage that is followed by a slower secondary degeneration related to noxious environment surrounding the degenerating cells. For example, retinal ishaemia may establish a cascade of changes that ultimately result in cell death: hypoxia leads to excitotoxic levels of glutamate, which cause a rise in intra-cellular calcium, which in turn, leads to neuronal death due to apoptosis or necrosis. Neuroprotection is a process that attempts to preserve the cells that were spared during the initial insult, but are still vulnerable to damage. Although not yet available, a neuroprotective agent would be of great use in arresting the progression of glaucoma. There is evidence that neuroprotection can be achieved both pharmacologically and immunologically. Pharmacological intervention aims at neutralising some of the effects of the nerve-derived toxic factors, thereby increasing the ability of the spared neurons to cope with stressful conditions. On the other hand, immunological interventions boost the body's own repair mechanisms for counteracting the toxic effects of various chemicals generated during the cascade. This review, based on a literature search using MEDLINE, focuses on diverse cellular events associated with glaucomatous neurodegeneration, and discusses some pharmacological agents believed to have a neuroprotective role in glaucoma. 相似文献
82.
Ram K Lam GN Chien B 《Journal of chromatography. B, Biomedical sciences and applications》2001,751(1):49-59
A method for determining concentration levels of ganaxolone in rat, monkey, dog and human plasma was validated in the range of 5-1500 ng/ml using a 200-microl plasma sample volume. This validation report describes the linearity, specificity. sensitivity, reproducibility, accuracy, recovery and stability of the analytical method. The inter-day C.V. ranged from 0.5 to 9.2%, intra-day C.V. from 0.7 to 8.8% and intra-day accuracy (mean absolute percentage difference) ranged from 0.0 to 14.0% for rat, monkey, dog and human plasma. The method was used for the routine analysis of ganaxolone in rat, monkey, dog and human plasma and summary of the pharmacokinetic data are presented. 相似文献
83.
Apoptosis in breast carcinoma 总被引:1,自引:0,他引:1
González-Cámpora R Galera Ruiz MR Vázquez Ramírez F Ríos Martín JJ Fernández Santos JM Ramos Martos MM Gómez Pascual A 《Pathology, research and practice》2000,196(3):167-174
Apoptosis may play a major role in determining tumor growth and aggressiveness. The aim of this study was to examine the relationship between apoptosis, expression of bcl-2 and p53 proteins, proliferation index, and other clinicopathological features of breast carcinoma. Sixty-five formalin-fixed paraffin-embedded tissue sections from invasive ductal breast carcinomas were studied for the presence of apoptosis by the terminaldeoxynucleotidyl-transferase-mediated dUTP-FITC nick end-labeling (TUNEL) method. Immunohistochemical methods were also used to determine the expression of estrogen receptor, Ki67, bcl-2 and p53 proteins. The number of apoptotic cells ranged from 2.0 to 236.0/10HPF (mean 36.26, median 28.0). The observation of 30 apoptotic cells/10HPF was more common in tumors > 3 cm, of histological grade III, with a high mitotic index, Ki67 index > or = 300, and p53 positivity; however, statistical significance was found only for the histological grade. Grade I and III tumors displayed an inverse association between the apoptotic index and bcl-2 and p53 protein expressions; grade I tumors frequently expressed bcl-2 (19/28), lacked p53 (20/28), and presented a low number of apoptotic cells (18/28), whereas grade III tumors tended to express p53 (12/17), lacked bcl-2 (13/17), and displayed a high number of apoptotic cells/10HPF (12/17). Multivariate analysis for survival revealed that estrogen receptors and apoptosis were independent variables. These data suggest that apoptosis, rather than proliferation index or expression of bcl-2 or p53 proteins, is an independent factor for the prognosis of survival. 相似文献
84.
N Le Berre D Heresbach M Kerbaol S Caulet J F Bretagne J Chaperon M Gosselin M P Ramée 《Journal of clinical pathology》1995,48(8):749-753
AIMS--To assess the value of histology in diagnosing inflammatory bowel disease (IBD) in colorectal biopsy specimens. METHODS--Retrospective, double blind evaluation of colorectal biopsy specimens from 41 patients with colitis (28 with ischaemic colitis and 13 with acute self-limited colitis) and 84 patients with IBD (42 with Crohn''s disease and 42 with ulcerative colitis). RESULTS--The features distinguishing IBD from other forms of colitis included distorted architecture, lymphocyte and plasma cell infiltrate, excess of polymorphonuclear leucocytes, polymorphonuclear cryptitis, crypt abscesses, and basal lymphoid aggregates. The features discriminating between Crohn''s disease and ulcerative colitis included an irregular or villous surface, distorted architecture, decrease in mucus content, and polymorphonuclear cryptitis. Using multivariate analysis, 90% of patients with Crohn''s disease and 71% of those with ulcerative colitis were correctly classified, the former being strongly defined by epithelioid granulomas, microgranulomas and isolated giant cells, and the latter best defined by an irregular or villous surface, decrease in mucus content and crypt atrophy. CONCLUSIONS--Examination of colorectal biopsy specimens is a reliable method for diagnosing IBD. In the absence of epithelioid granulomas, microgranulomas and isolated giant cells a diagnosis of Crohn''s disease is based on the absence of histological criteria favouring ulcerative colitis. The histological spectrum of indeterminate colitis remains to be clarified. 相似文献
85.
Immunohistochemical characterization of fibroblast subpopulations in normal peritoneal tissue and in peritoneal dialysis-induced fibrosis 总被引:7,自引:0,他引:7
Jiménez-Heffernan JA Aguilera A Aroeira LS Lara-Pezzi E Bajo MA del Peso G Ramírez M Gamallo C Sánchez-Tomero JA Alvarez V López-Cabrera M Selgas R 《Virchows Archiv : an international journal of pathology》2004,444(3):247-256
Peritoneal fibrosis is one of the most common morphological changes observed in continuous ambulatory peritoneal dialysis (CAPD) patients. Both resident fibroblasts and new fibroblast-like cells derived from the mesothelium by epithelial-to-mesenchymal transition are the main cells involved fibrogenesis. In order to establish markers of peritoneal impairment and pathogenic clues to explain the fibrogenic process, we conducted an immunohistochemical study focused on peritoneal fibroblasts. Parietal peritoneal biopsies were collected from four patient groups: normal controls (n=15), non-CAPD uremic patients (n=17), uremic patients on CAPD (n=27) and non-renal patients with inguinal hernia (n=12). To study myofibroblastic conversion of mesothelial cells, -smooth muscle actin (SMA), desmin, cytokeratins and E-cadherin were analyzed. The expression of CD34 by fibroblasts was also analyzed. Fibroblasts from controls and non-CAPD uremic patients showed expression of CD34, but no myofibroblastic or mesothelial markers. The opposite pattern was present during CAPD-related fibrosis. Expression of cytokeratins and E-cadherin by fibroblast-like cells and -SMA by mesothelial and stromal cells supports that mesothelial-to-myofibroblast transition occurs during CAPD. Loss of CD34 expression correlated with the degree of peritoneal fibrosis. The immunophenotype of fibroblasts varies during the progression of fibrosis. Myofibroblasts seem to derive from both activation of resident fibroblasts and local conversion of mesothelial cells.Manuel López-Cabrera and Rafael Selgas contributed equally to the article. 相似文献
86.
Frank H. DeLand Arthur Lieber Madhira D. Ram David M. Goldenberg 《European journal of nuclear medicine and molecular imaging》1986,12(9):429-435
In 12 consecutive patients with suspected metastatic carcinoma of the liver, we evaluated the sensitivity of radiolabeled antibodies to tumor antigens, magnetic resonance imaging, and X-ray computed tomography imaging in the detection of hepatic malignancies. Studies were performed with 131I labeled antibodies to CEA and/or CSAp; polyclonal, monoclonal and F(ab)2 antibodies were used. Nontarget radioactivity was diminished by administration of 99mTc reagents simulating nontumor distribution and use of a computer substraction method. In nine patients with confirmed liver neoplasms, radioimunodetection disclosed the foci of hepatic malignancies. In three patients with suspected liver neoplasms, the antibody studies were positive, but at this time have not been confirmed. X-ray computed tomography each disclosed mass lesions in five patients and magnetic resonance in three. These findings suggest that radioimmunodetection provides greater accuracy in the detection and localization of cancer than other diagnostic modalities currently used.This research was supported in part by NIH Grants CA37408, CA37409, CA37412, and CA39841 相似文献
87.
Mohammad Abumayyaleh Iván J. Núñez Gil Ibrahim El-Battrawy Vicente Estrada Víctor Manuel Becerra-Muñoz Alvaro Aparisi Inmaculada Fernández-Rozas Gisela Feltes Ramón Arroyo-Espliguero Daniela Trabattoni Javier López-País Martino Pepe Rodolfo Romero Diego Raúl Villavicencio García Carloalberto Biole Thamar Capel Astrua Charbel Maroun Eid Emilio Alfonso Ibrahim Akin 《Obesity research & clinical practice》2021,15(3):275-280
BackgroundObesity has been described as a protective factor in cardiovascular and other diseases being expressed as ‘obesity paradox’. However, the impact of obesity on clinical outcomes including mortality in COVID-19 has been poorly systematically investigated until now. We aimed to compare clinical outcomes among COVID-19 patients divided into three groups according to the body mass index (BMI).MethodsWe retrospectively collected data up to May 31st, 2020. 3635 patients were divided into three groups of BMI (<25 kg/m2; n = 1110, 25?30 kg/m2; n = 1464, and >30 kg/m2; n = 1061). Demographic, in-hospital complications, and predictors for mortality, respiratory insufficiency, and sepsis were analyzed.ResultsThe rate of respiratory insufficiency was more recorded in BMI 25?30 kg/m2 as compared to BMI < 25 kg/m2 (22.8% vs. 41.8%; p < 0.001), and in BMI > 30 kg/m2 than BMI < 25 kg/m2, respectively (22.8% vs. 35.4%; p < 0.001). Sepsis was more observed in BMI 25?30 kg/m2 and BMI > 30 kg/m2 as compared to BMI < 25 kg/m2, respectively (25.1% vs. 42.5%; p = 0.02) and (25.1% vs. 32.5%; p = 0.006). The mortality rate was higher in BMI 25?30 kg/m2 and BMI > 30 kg/m2 as compared to BMI < 25 kg/m2, respectively (27.2% vs. 39.2%; p = 0.31) (27.2% vs. 33.5%; p = 0.004). In the Cox multivariate analysis for mortality, BMI < 25 kg/m2 and BMI > 30 kg/m2 did not impact the mortality rate (HR 1.15, 95% CI: 0.889?1.508; p = 0.27) (HR 1.15, 95% CI: 0.893?1.479; p = 0.27). In multivariate logistic regression analyses for respiratory insufficiency and sepsis, BMI < 25 kg/m2 is determined as an independent predictor for reduction of respiratory insufficiency (OR 0.73, 95% CI: 0.538?1.004; p = 0.05).ConclusionsHOPE COVID-19-Registry revealed no evidence of obesity paradox in patients with COVID-19. However, Obesity was associated with a higher rate of respiratory insufficiency and sepsis but was not determined as an independent predictor for a high mortality. 相似文献
88.
César Cuevas-Lara Mikel Izquierdo Mikel L. Sáez de Asteasu Robinson Ramírez-Vélez Fabiola Zambom-Ferraresi Fabricio Zambom-Ferraresi Nicolás Martínez-Velilla 《Journal of the American Medical Directors Association》2021,22(2):364-371.e1
ObjectivesTo examine the effectiveness of game-based interventions compared with usual care on health-related outcomes for acutely hospitalized older patients.DesignSystematic review of randomized controlled trials (RCT) and nonrandomized trials.Setting and ParticipantsAdults aged 65 years or older admitted to an Acute Care for Elderly unit were selected.MeasuresHealth-related outcomes (eg, functional capacity, quality of life, adherence to treatment).ResultsFour RCTs were included in the review. The interventions were based on the implementation of serious-game programs using Nintendo Wii in acute medical patients. Across the included studies, no significant differences were observed between groups on functional capacity and health-related quality of life. Significant differences were found between groups on the adherence to treatment (in favor of the control group), but no differences were obtained in other outcomes such as enjoyment and motivation.Conclusions and ImplicationsIn general, there is very limited evidence for the efficacy to reach conclusions about the effects of game-based interventions on health-related outcomes in acutely hospitalized older patients. Future studies are needed to improve our knowledge in the field; however, we consider that these strategies should be considered in the future complementary to usual care. 相似文献
89.
Layland Eric K. Caldwell Linda L. Ram Nilam Smith Edward A. Wegner Lisa Jacobs Joachim J. 《Prevention science》2022,23(7):1251-1263
Prevention Science - An earlier trial of a school-based, preventative intervention, HealthWise South Africa, demonstrated some efficacy in preventing adolescent drinking and smoking in the Western... 相似文献
90.
P. Gayarre Abril J. Subirá Ríos L. Muñiz Suárez C. Murillo Pérez M. Ramírez Fabián J.I. Hijazo Conejos P. Medrano Llorente J. García-Magariño Alonso F.X. Elizalde Benito G. Aleson Hornos L. Pérez Abad J. Rioja Zuazu C. García Artal B. Blasco Beltrán P. Carrera Lasfuentes C. Marín Zaldivar 《Actas urologicas espa?olas》2021,45(4):247-256