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81.
Human vascular endothelial cells with extended life spans: in vitro cell response,protein expression,and angiogenesis 总被引:4,自引:0,他引:4
Gagnon E Cattaruzzi P Griffith M Muzakare L LeFlao K Faure R Béliveau R Hussain SN Koutsilieris M Doillon CJ 《Angiogenesis》2002,5(1-2):21-33
An in vitro angiogenesis system was designed for screening angiogenic agonists and antagonists. In order to obtain large quantities of cells and reproducibility, human endothelial cells with extended life spans were developed by retroviral transfection. The resulting cells grown in a serum-free medium containing endothelial cell growth supplement (ECGS) have a telomerase activity, extended life spans of at least 21 passages, and an endothelial cell phenotype (diI-acetylated-LDL upake, factor VIII-related antigen, VEGFR-1 and R-2, and tissue-type plasminogen activator (tPA)) that resembled that of unaltered primary endothelial cells. Exceptions were (i) a higher expression of tPA, and (ii) a non-significant growth response to FGF-2 or VEGF stimulation. Within three-dimensional fibrin gels, specific cell clones rapidly formed tubular structures in a more reproducible manner than those observed with low-passage primary cells. Tube formation by primary endothelial cells and those with extended life spans was dependent upon FGF-2 and ECGS, respectively. Both cell types produced FGF-2 and VEGF cytokines. Increasing doses of suramin significantly decreased the size of microvessels formed by both cell lines. These functional results indicate that a vascular matrix system containing human cells with extended life spans can be successfully utilized as an in vitro assay for antiangiogenic compounds. 相似文献
82.
Dimitar Divchev Edith Katharina Podewski Michael Mengel Gerd Peter Meyer Helmut Drexler Arnd Schaefer 《European journal of echocardiography》2007,8(4):298-302
We are presenting a case of floating left and right atrial formations on an atrial septal defect occluder system (23mm StarFLEX)-Occluder) initially supposed to be thrombotic appositions in a 57-year-old man. The closure was performed on the background of left hemispheric stroke and atrial septal aneurysm (ASA) with patent foramen ovale (PFO). The suspect structures were detected in the 6-month follow-up by transesophageal echocardiography (TEE). The patient underwent a successful surgical explantation of the closure device and closure of the patent foramen ovale (PFO) using a pericardial patch. The pathological evaluation of the biatrial device associated appositions revealed hytrophic heart muscle tissue with perifocal scarring and purulent abscess-forming, granulating and foam-cell including inflammatory foreign body reaction instead of the expected thrombus formation. 相似文献
83.
84.
Longer Time Interval Between Completion of Neoadjuvant Chemoradiation and Surgical Resection Does Not Improve Downstaging of Rectal Carcinoma 总被引:4,自引:2,他引:4
Stein DE Mahmoud NN Anné PR Rose DG Isenberg GA Goldstein SD Mitchell E Fry RD 《Diseases of the colon and rectum》2003,46(4):448-453
PURPOSE: An interval of six to eight weeks between completion of preoperative chemoradiation therapy and surgical resection of advanced rectal cancer has been described. Our purpose was to determine whether a longer time interval between completion of therapy and resection increases tumor downstaging and affects perioperative morbidity. METHODS: Forty patients with advanced adenocarcinoma of the rectum underwent preoperative chemoradiation on a prospective trial with irinotecan (50 mg/m2), 5-fluorouracil (225 mg/m2), and concomitant external-beam radiation (45-54 Gy) followed by complete surgical resection of the tumor with total mesorectal excision. The time interval between completion of chemoradiation and surgical resection ranged from 28 to 97 days. The patients were divided into two groups with 33 eligible patients: Group A (4-week to 8-week time interval; 28-56 days) and Group B (10-week to 14-week interval; 67-97 days). Tumor downstaging was compared between these two groups. The number of patients downstaged by at least one T stage, those downstaged by at least one N stage, those with pathologic complete responses, and those with only residual microscopic tumor foci were compared. Postoperative length of stay, estimated blood loss, perioperative morbidity, and sphincter-sparing procedures were also compared. Chi-squared tests and Student's t-test were calculated. RESULTS: Group A had 19 patients, and Group B had 14 patients. Patient demographics were comparable. Mean age was 52 years, and 70 percent of patients were male. There were no deaths. There were no statistical differences in perioperative morbidity, with three anastomotic leaks in Group A. Tumors were downstaged in 58 percent of patients in Group A and 43 percent of those in Group B (P = 0.61). Nodal downstaging occurred in 78 percent of Group A and 67 percent of Group B (P = 0.9). The pathologic complete response rate was 21 percent in Group A and 14 percent in Group B (P = 0.97), and a residual microfocus of tumor was found in 33 percent of patients in Group A and 42 percent of those in Group B (P = 0.90). These differences were not statistically significant. CONCLUSIONS: Perioperative morbidity is not affected by longer intervals. A longer interval between completion of neoadjuvant chemoradiation and surgical resection may not increase the tumor response rate of advanced rectal cancer in this cohort. 相似文献
85.
Brain Gray and White Matter Volume Loss Accelerates with Aging in Chronic Alcoholics: A Quantitative MRI Study 总被引:15,自引:0,他引:15
Adolf Pfefferbaum Kelvin O. Lim Robert B. Zipursky Daniel H. Mathalon Margaret J. Rosenbloom Barton Lane Chung Nim Ha Edith V. Sullivan 《Alcoholism, clinical and experimental research》1992,16(6):1078-1089
Magnetic resonance imaging (MRI) was used to study in vivo the brains of 49 patients with chronic alcoholism, 3 to 4 weeks post-withdrawal, and 43 normal healthy controls, all right-handed male veterans between the ages of 23 and 70 years. MRI scans were analyzed using a semi-automated procedure, which allowed the subcortical regions to be segmented into cerebrospinal fluid (CSF) and brain tissue and the cortical regions to be segmented into CSF, gray matter, and white matter. An age regression model was used to examine the effects of alcohol on brain structure, over and above that expected from the normal aging process. The alcoholics exhibited decreased tissue and increased CSF after correcting for aging. In the cortex, there was significant loss of both gray matter and white matter volume. In this sample of alcoholics, no particular cortical region was preferentially affected or spared. Furthermore, brain tissue volume loss increased with advanced age in the alcoholics. In this group of alcoholics there was no relationship between length of illness and age, i.e., the younger alcoholics had as heavy alcohol use histories as did the older alcoholics. Thus, the increased brain tissue loss with advanced age is interpreted as evidence for age-related increase in brain vulnerability to chronic alcohol abuse. 相似文献
86.
Pyogenic liver abscess with a focus on Klebsiella pneumoniae as a primary pathogen: an emerging disease with unique clinical characteristics 总被引:5,自引:0,他引:5
OBJECTIVES: Pyogenic liver abscess is a common intraabdominal infection. Historically, Escherichia coli (E. coli) has been the predominant causative agent. Klebsiella liver abscess (KLA) was first reported in Taiwan and has surpassed E. coli as the number one isolate from patients with hepatic abscesses in that country and reports from other countries, including the United States, have increased. We examined the microbiologic trends of pyogenic liver abscess at our institution to determine if a similar shift in etiologic agents was occurring. METHODS: We examined all cases of liver abscess at our institution from 1999 to 2003 via a retrospective chart review of inpatient records and reviewed the English literature via a MEDLINE search for all U.S. cases of KLA. RESULTS: Since 1966, only 12 cases of KLA have been reported in the United States. We report six cases of KLA at our institution alone; 2 patients were not Asian, and 4 were not diabetic. Klebsiella pneumoniae (K. pneumoniae) was the most common cause of pyogenic hepatic abscess at our institution over the last 5-yr period. When comparing Klebsiella versus other causes of pyogenic liver abscess, there were no significant differences in demographics or laboratory findings; however, most of our Klebsiella cases occurred among Filipinos. Review of the 18 cases of K. pneumoniae liver abscess in the United States showed that Klebsiella cases occurred predominantly among middle-aged men; 83% had concurrent bacteremia and 28% had metastatic complications. An increasing number of cases were reported from the United States since the mid-1990s. CONCLUSIONS: These data suggest that KLA may represent an emerging disease in Western countries, such as the United States. The diagnosis of K. pneumoniae should be considered in all cases of liver abscess, and appropriate antibiotic therapy and a diagnostic work-up for metastatic complications should be employed. 相似文献
87.
Elizabeth W. Sorensen Abigail L. Sedlacek Joanne Y. H. Lim Denise Skrombolas John G. Frelinger Edith M. Lord 《Immunology》2013,138(3):280-292
The tumour microenvironment is complex containing not only neoplastic cells but also a variety of host cells. The heterogeneous infiltrating immune cells include subsets of cells with opposing functions, whose activities are mediated either directly or through the cytokines they produce. Systemic delivery of cytokines such as interleukin‐2 ( IL‐2) has been used clinically to enhance anti‐tumour responses, but these molecules are generally thought to have evolved to act locally in a paracrine fashion. In this study we examined the effect of local production of IL‐2 on the growth and the immune response to B16 melanoma cells. We found that the local production of IL‐2 enhances the number of interferon‐γ‐expressing CD8 T and natural killer cells in the tumour, as well as inducing expression of vascular cell adhesion molecule 1 on tumour vessels. These responses were largely absent in interferon‐γ knockout mice. The expression of IL‐2 in the tumour microenvironment decreases tumour growth despite also enhancing Foxp3+ CD4+ regulatory T cells and anti‐inflammatory cytokines such as IL‐10. Higher levels of IL‐2 in the tumour microenvironment eliminated the progressive growth of the B16 cells in vivo, and this inhibition was dependent on the presence of either T cells or, to a lesser extent, natural killer cells. Surprisingly however, the B16 tumours were not completely eliminated but instead were controlled for an extended period of time, suggesting that a form of tumour dormancy was established. 相似文献
88.
Jesús K. Yamamoto-Furusho Jorge L. De-León-Rendón Monica García de la Torre Edith Alvarez-León Gilberto Vargas-Alarcón 《Immunology letters》2013,149(1-2):50-53
Interleukin (IL)-20 belongs to the IL-10 family and is a potent immunomodulatory cytokine with implications for pathogenesis in the inflammatory bowel disease (IBD). The interleukin 20 gene is located within a 200 kb region of q31-32 locus of chromosome 1. No previous studies have reported this novel association between ulcerative colitis (UC) and IL-20 polymorphisms. In the present work, we evaluated the role of IL-20 gene polymorphisms as susceptibility markers for UC. Three polymorphisms of IL-20 gene (rs2981573, rs2232360, rs1518108) were genotyped by 5′ exonuclease TaqMan genotyping assays on an ABI Prism 7900 HT Fast Real-Time PCR system in a group of 198 Mexican Mestizo patients with UC and 698 ethnically matched healthy unrelated individuals with no family history of UC. We found significant decreased frequencies of two IL-20 genotypes: GG (rs2981573) [10.6% vs. 17.6%, p = 0.017, OR = 0.55, 95% CI: 0.33–0.93] and GG (rs2232360) [10.6% vs. 17.6%, p = 0.017, OR = 0.55, 95% CI: 0.33–0.93] in UC patients as compared to healthy controls. No significant differences of gene frequencies were found between UC patients and healthy controls in the rs1518108 polymorphism. In the subgroup analysis, no differences were found between the IL-20 genotypes and the clinical characteristics of UC. The results suggest that the GG genotypes of the IL-20 polymorphisms (rs2981573 and rs2232360) might have an important role in the development of UC in the Mexican population. 相似文献
89.
Annemiek J. Linn Julia C.M. van Weert Edith G. Smit Kate Perry Liset van Dijk 《Patient education and counseling》2013
Objective
To describe the development of a theoretical and evidence-based tailored multimedia intervention to improve medication intake behavior in patients with inflammatory bowel disease (IBD). The intervention integrates interpersonal and technology-mediated strategies with the expectation that this will work synergistically.Methods
The development followed the Medical Research Council's framework. Three literature reviews and three pre-tests among 84 IBD patients and eight nurses were conducted to guide the development of the intervention. A feasibility study was carried out among four nurses and 29 patients.Results
The components include: (1) an online preparatory assessment (OPA); (2) tailored interpersonal communication; and (3) tailored text messaging. To support the development, the feasibility was tested. Results indicated that the OPA was comprehensive and could be a helpful tool for both patients and nurses to prepare for the consultation. The training was evaluated as being instructive and applicable with a mean mark of 8.5. Of the developed messages, 65.6% received positive evaluations and were used in the intervention.Conclusion
By applying the framework, we were able to describe the logic behind the development of a tailored multimedia intervention to improve medication intake behavior.Practice implications
This study could serve as a guide for the development of other health interventions. 相似文献90.
Thorsten Mikoteit Serge Brand Johannes Beck Sonja Perren Agnes Von Wyl Kai Von Klitzing Edith Holsboer‐Trachsler Martin Hatzinger 《Journal of sleep research》2013,22(2):129-136
Sleep electroencephalogram spindles are associated with efficient cortical–subcortical connectivity, and intellectual and learning abilities. In the present study, we assessed healthy preschoolers with a twofold aim: (i) to explore associations of non‐rapid eye movement S2 spindles with emotional/behavioural characteristics cross‐sectionally; and (ii) longitudinally. A total of 43 children who were 5 years old underwent objective sleep electroencephalogram monitoring in their homes. Emotional and behavioural dimensions were assessed by parents and teachers with the Strengths & Difficulties Questionnaire at baseline and at follow‐up 1 year later. Non‐rapid eye movement S2 spindles were visually scored and compared with Strengths & Difficulties Questionnaire dimensions. High non‐rapid eye movement S2 spindle density was associated with less internalizing behaviour, more prosocial behaviour and a low total problem score. In girls, high non‐rapid eye movement S2 spindle density was related to low hyperactivity, while in boys it was associated with less internalizing behaviour, more externalizing behaviour and more hyperactivity. Longitudinally, a higher number of non‐rapid eye movement S2 spindles at 5 years old predicted fewer peer problems 12 months later. In kindergarten children, high non‐rapid eye movement S2 spindle density is associated with observable current and future favourable emotional/behavioural patterns. However, gender differences were also found, as should be taken into account in future studies. 相似文献