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Monocyte chemotactic protein expression during schistosome egg granuloma formation. Sequence of production, localization, contribution, and regulation. 总被引:11,自引:6,他引:5
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S. W. Chensue K. S. Warmington N. W. Lukacs P. M. Lincoln M. D. Burdick R. M. Strieter S. L. Kunkel 《The American journal of pathology》1995,146(1):130-138
The present study explored the role of murine monocyte chemotactic protein (MCP) in the T cell-mediated hypersensitive granulomatous response to Schistosoma mansoni eggs. The study examined the time course of local production, contribution to cellular infiltration, and the role of T cells in endogenous regulation. Synchronized pulmonary granulomas were induced under conditions of primary and secondary states of immunity. Primer-directed polymerase chain reaction analysis showed increased MCP mRNA expression in granulomatous lungs, mainly in the secondary response. Levels of MCP were measured by enzyme-linked immunosorbent assay in cultures of intact granulomas. Spontaneous MCP production was modest in primary granuloma cultures, reaching a maximum of 5.7 +/- 0.9 ng/ml by 16 days. In contrast, the secondary response showed augmented and accelerated production, achieving 13 +/- 2.0 ng/ml by 2 days. Immunohistochemical staining revealed the strongest MCP expression within microvascular adventitial cells or pericytes as well as in scattered mononuclear cells associated with granulomas. Staining was not detected in normal lungs. Passive immunization with anti-MCP-1 antibodies caused a 40% reduction in the secondary granuloma area but did not significantly affect the primary response. With adoptive cell transfer and T cell subset depletion, it was shown that Thy-1+ and CD5+ cells augmented, whereas CD8+ cells appeared to impair, MCP production. This provides direct evidence that MCP is involved in secondary Th2-mediated response to schistosome eggs and is subject to regulation by T cells. 相似文献
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A convenience sample of hospital workers, those receiving influenza vaccine and those not receiving vaccine, were asked to complete questionnaires delineating the occurrence of symptoms (e.g., fever, headache, extreme tiredness, dry cough, sore throat, runny nose, stuffy nose, muscle aches) and absenteeism in the 7-day period post-vaccination if vaccinated. Those unvaccinated completed the questionnaire in a self-selected 7 consecutive day period during the study conducted from November 2004 to February 2005. Those receiving either Fluzone or FluMist reported significantly fewer symptoms and related absenteeism than the unvaccinated group (p < .05). Administration of influenza vaccine did not result in higher rates of post-vaccination symptoms as compared to an unvaccinated group. Further, vaccinated employees did not experience higher absenteeism rates as a result of receiving either influenza vaccine. However, for those reporting absenteeism as a result of symptoms, mean absenteeism days were highest in the FluMist group (4.5 days) compared to the unvaccinated group (2.1 days) and the Fluzone group (1.9 days). 相似文献
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Study DesignSystematic review.IntroductionContrast baths are used as an intervention in hand therapy, yet it is unclear which patients, if any, benefit from this intervention.Purpose of the StudyTo examine the nature and quality of the evidence regarding the use of contrast baths using a systematic review process.MethodsOf a total of 28 clinical research articles on contrast baths, from 1938 forward, ten met the inclusion criteria set by the authors.ResultsThese studies addressed the physiological changes of hot and cold on blood flow, intramuscular temperature, subcutaneous temperature, and the influence of room temperature and age. The subjects included normal/healthy volunteers and patients with a diagnosis of rheumatoid arthritis, diabetes, or foot/ankle injuries. The diversity of conditions, protocols, and outcomes limited the ability to make definitive conclusions on efficacy.ConclusionsThe contrast bath procedure may increase superficial blood flow and skin temperature, though the evidence on the impact on edema is conflicting. No relationship between physiologic effects and functional outcomes has been established.Level of Evidence: 2A 相似文献
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Natural history of aortoarteritis (Takayasu's disease) 总被引:8,自引:0,他引:8
The natural history of aortoarteritis was studied in 88 patients (54 women and 34 men). The average age was 24.0 +/- 8.8 years at onset of symptoms and 28.3 +/- 9.9 years at diagnosis. The follow-up period was 83.6 +/- 74.4 months from onset and 33.2 +/- 37.0 months from diagnosis. Ten patients (11.4%) died during follow-up (0.016 deaths/patient year), and 22 patients (25%) suffered major nonfatal events (0.042 events/patient year). The cumulative survival at 5 and 10 years after the onset was 91.0 +/- 3.3% and 84.0 +/- 5.6% (mean +/- SEM), respectively. The event-free survival rates at the same intervals after onset were 74.9 +/- 5.0% and 64.0 +/- 7.4%, respectively. The overall survival and event-free survival at 10 years after diagnosis was 80.3 +/- 6.5% and 61.6 +/- 7.5%, respectively. Patients with no complications or a mild single complication at diagnosis had a higher event-free survival rate than those with severe single complication or multiple complications at 5 years--97.0 +/- 2.9% and 59.7 +/- 7.3%, respectively (p less than 0.001). Severe hypertension (p less than 0.01), severe functional disability (p less than 0.01), and evidence of cardiac involvement (p less than 0.05) were good predictors of either death or major event on follow-up. These data are useful in making an objective assessment of the prognosis and in planning elective interventions. 相似文献
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Belinda Joy Deal Rebecca A Fountain Carol Ann Russell-Broaddus Melinda Stanley-Hermanns 《Disaster Management & Response》2006,4(4):100-105
Hurricanes Katrina and Rita forced many individuals along the coast of Texas and Louisiana to seek shelter inland. Among the evacuees were residents with special needs and residents of nursing homes and group homes caring for mentally retarded and physically disabled persons. Many nurses volunteered to provide health care for those in need. This article discusses challenges and opportunities that were encountered by nurses volunteering in special-needs shelters. Issues related to human and physical resources, patient care, and confidentiality are discussed including lessons learned. As nurses who cared for evacuees in the shelter, it is hoped some of the lessons learned can be utilized in future disasters. 相似文献
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R F Rossi R Ekroth K Jansson M Scallan R J Thompson C Lincoln 《Scandinavian journal of thoracic and cardiovascular surgery》1990,24(1):75-77
The concentration of brain type creatine kinase (CK-BB) was measured in blood from the internal jugular vein in 32 children (less than 1 year old) with congenital heart disease. In transposition of the great arteries the CK-BB levels were significantly higher than in children without cyanosis (10.1 +/- 4.1 vs. 3.0 +/- 0.5 ng/ml). A negative correlation was found for CK-BB concentration and arterial oxygen saturation (r = -0.41, p less than 0.02 for all children and r = -0.62, p less than 0.05 for those with tetralogy of Fallot). It is suggested that the increased CK-BB levels in the blood of cyanotic children reflect chronic cerebral hypoxia, which may explain other reports of reduced psycho-intellectual function in patients with cyanotic heart disease. 相似文献
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Sanjeev Kakar Thomas A Einhorn Siddharth Vora Lincoln J Miara Gregory Hon Nathan A Wigner Daniel Toben Kimberly A Jacobsen Maisa O Al-Sebaei Michael Song Philip C Trackman Elise F Morgan Louis C Gerstenfeld George L Barnes 《Journal of bone and mineral research》2007,22(12):1903-1912
Studies have shown that systemic PTH treatment enhanced the rate of bone repair in rodent models. However, the mechanisms through which PTH affects bone repair have not been elucidated. In these studies we show that PTH primarily enhanced the earliest stages of endochondral bone repair by increasing chondrocyte recruitment and rate of differentiation. In coordination with these cellular events, we observed an increased level of canonical Wnt-signaling in PTH-treated bones at multiple time-points across the time-course of fracture repair, supporting the conclusion that PTH responses are at least in part mediated through Wnt signaling. INTRODUCTION: Since FDA approval of PTH [PTH(1-34); Forteo] as a treatment for osteoporosis, there has been interest in its use in other musculoskeletal conditions. Fracture repair is one area in which PTH may have a significant clinical impact. Multiple animal studies have shown that systemic PTH treatment of healing fractures increased both callus volume and return of mechanical competence in models of fracture healing. Whereas the potential for PTH has been established, the mechanism(s) by which PTH produces these effects remain elusive. MATERIALS AND METHODS: Closed femoral fractures were generated in 8-wk-old male C57Bl/6 mice followed by daily systemic injections of either saline (control) or 30 microg/kg PTH(1-34) for 14 days after fracture. Bones were harvested at days 2, 3, 5, 7, 10, 14, 21, and 28 after fracture and analyzed at the tissue level by radiography and histomorphometry and at the molecular and biochemical levels level by RNase protection assay (RPA), real-time PCR, and Western blot analysis. RESULTS: Quantitative muCT analysis showed that PTH treatment induced a larger callus cross-sectional area, length, and total volume compared with controls. Molecular analysis of the expression of extracellular matrix genes associated with chondrogenesis and osteogenesis showed that PTH treated fractures displayed a 3-fold greater increase in chondrogenesis relative to osteogenesis over the course of the repair process. In addition, chondrocyte hypertrophy occurred earlier in the PTH-treated callus tissues. Analysis of the expression of potential mediators of PTH actions showed that PTH treatment significantly induced the expression of Wnts 4, 5a, 5b, and 10b and increased levels of unphosphorylated, nuclear localized beta-catenin protein, a central feature of canonical Wnt signaling. CONCLUSIONS: These results showed that the PTH-mediated enhancement of fracture repair is primarily associated with an amplification of chondrocyte recruitment and maturation in the early fracture callus. Associated with these cellular effects, we observed an increase in canonical Wnt signaling supporting the conclusion that PTH effects on bone repair are mediated at least in part through the activation of Wnt-signaling pathways. 相似文献