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951.
BACKGROUND: T-cell receptor transgenic (TCR-tg) mouse models with direct CD4 alloreactivity will help elucidate mechanisms of transplant rejection and tolerance in vivo. Although such models exist, they are limited by unusual strain combinations or are based on model antigens. METHODS: A TCR-tg mouse with direct CD4 specificity in the widely used BALB/c donor --> C57BL/6 host strain combination was created. This TCR-tg mouse, named 4C, was selected for reactivity against BALB/c dendritic cells in order to model early priming events after transplantation. The response of 4C T cells to skin and heart transplants were characterized. RESULTS: The alloantigen is restricted by I-A and appears to be widely distributed in mouse tissues. 4C T cells are able to acutely reject skin but not heart allografts. Paradoxically, heart grafts elicited a stronger proliferation and effector function of TCR-tg T cells than skin grafts. 4C T cells caused cardiac allograft vasculopathy in the absence of other T cells and alloantibodies, suggesting a role for the direct pathway in chronic rejection. Augmentation of priming with an infusion of donor-derived dendritic cells resulted in acute heart allograft rejection by 4C T cells, demonstrating that the level of priming can play a role in determining acute versus chronic rejection by the CD4 direct pathway. CONCLUSIONS: Rejection of a graft by the direct CD4 pathway is determined by graft susceptibility to rejection, as well as the degree of T-cell priming caused by the graft. Grafts that are not acutely rejected can develop transplant vasculopathy mediated by the direct CD4 T cells. 相似文献
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953.
Thal S Thai H Juneman E Goldman S 《Pacing and clinical electrophysiology : PACE》2008,31(9):1184-1185
Coronary sinus diverticula are rare findings usually associated with the presence of accessory pathways. We report the case of a 74-year-old man, who underwent cardiac resynchronization therapy (CRT) device implant. Coronary sinus diverticulum was an incidental finding while attempting to subselectively cannulate the coronary sinus for left ventricle lead implant. The case was able to be completed without complications. 相似文献
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Matthew M. Carrick C. Anne Morrison M.D. D. Jacob Alexis M.D. Mark A. Feanny M.D. Hoang Q. Pham M.D. Francis J. Welsh M.D. Michael A. Norman M.D. Bradford G. Scott M.D. 《American journal of surgery》2009,198(1):64-69
Background
Shotgun wound classification systems attempt to predict the need for surgical intervention based on the size of wounds, pellet spread, or distance from the weapon rather than clinical findings.Methods
A 5-year retrospective review of patients sustaining a thoracoabdominal shotgun wound was performed. Factors believed to be associated with the need for surgical intervention were examined using the Fisher exact test or an independent sample t test.Results
Sixty-four patients suffered a thoracoabdominal shotgun wound. Fifty-nine percent required surgical intervention. Factors significantly associated with the need for surgical intervention were a low revised trauma score and systolic and diastolic blood pressure (P < .05). Distance from attacker, wound patterns, pellet size, and pellet spread were not found to have an association.Conclusions
Clinical indicators of hemorrhage and shock are associated with the need for surgical intervention, whereas pellet spread, pellet size, and distance from the attacker are not. This is a significant departure from traditional classification systems. 相似文献956.
Liow K Ablah E Nguyen JC Sadler T Wolfe D Tran KD Guo L Hoang T 《Epilepsy & behavior : E&B》2007,10(4):576-582
Complementary and alternative medicine (CAM) is recognized to be commonly used by patients, yet there have been few studies regarding the scope of CAM use by patients with epilepsy. This study assessed usage and perceptions of CAM by patients with epilepsy in the midwest of the United States. A 25-item survey was administered to adult patients with epilepsy, and data were collected from 228 patients. The survey collected demographics, specific CAM usage, adverse effects of CAM therapy, and perceptions of the effectiveness of CAM. Thirty-nine percent reported using CAM; 25% reported using CAM specifically for their epilepsy. Prayer/spirituality was the most commonly used form of CAM (46%), followed by "mega" vitamins (25%), chiropractic care (24%), and stress management (16%). CAM use is common among midwestern patients with epilepsy, although the pattern of use may be slightly different than in other regions of the United States and elsewhere. 相似文献
957.
Thai H Guarraia D Johnson N Goldman S Gaballa MA 《Journal of cardiovascular pharmacology》2007,50(6):703-707
Angiotensin II receptor blockade (ARB) increases vasorelaxation in heart failure by enhancing endothelial nitric oxide (NO). To determine the effects of valsartan on NO-mediated peripheral vascular function after myocardial infarction (MI), we treated adult male Sprague-Dawley rats immediately after MI with valsartan for 3 weeks (sham, n = 10; MI, n = 11) and 6 weeks (sham, n = 6; MI, n = 8). At both time points, valsartan lowered (P < 0.05) left ventricular (LV) systolic pressure (103 +/- 4 and 107 +/- 4 vs. 93 +/- 3 and 85 +/- 4 mm Hg, respectively) and LV end-diastolic pressure (25 +/- 1 and 25 +/- 2 to 13 +/- 2 and 18 +/- 3 mm Hg, respectively). Valsartan lowered (P < 0.05) LV dP/dt only at 6 weeks (4676 +/- 168 and 4503 +/- 232 vs. 4539 +/- 281 and 3372 +/- 417 mm Hg/sec); valsartan shortened (P < 0.05) the time constant of LV relaxation or tau only at 3 weeks (24.2 +/- 1.8 and 26.5 +/- 2.3 vs. 20.1 +/- 0.7 and 23.8 +/- 1.4 msec). At 6 weeks, the vasorelaxation response to acetycholine in aortic rings was decreased (P < 0.05) with MI and improved at acetycholine doses (10, 10, and 10; P < 0.06) with valsartan. Endothelial nitric oxide synthase (eNOS) protein was undetectable in aortic tissue from valsartan treated rats or from aortic tissue incubated with valsartan (2.5, 25, and 50 mg/mL). These data suggest that valsartan improves cardiac function after MI by modulating LV remodeling, decreasing LV end-diastolic pressure, and enhancing both LV diastolic and endothelial function. These effects are mediated, in part, by NO but upregulation of eNOS may not be required for improved systemic endothelial function in heart failure. 相似文献
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960.
Binard A Alassane S Devauchelle-Pensec V Berthelot JM Jousse-Joulin S Chalés G Le Henaff C Thorel JB Hoang S Youinou P Saraux A 《The Journal of rheumatology》2007,34(12):2351-2357
OBJECTIVE: To evaluate clinical, laboratory, and radiological features and outcomes in patients with monoarthritis (MA), identified in a cohort of patients with early arthritis. METHODS: A cohort of 270 patients with undiagnosed arthritis of less than 1 year's duration was divided into 3 groups: single episode of MA (MA, n = 27), MA with a history of patient-reported arthritis (MA + past, n = 23), and oligo- or polyarthritis (OA/PA, n = 220). At 6-month intervals, all patients underwent a standardized examination, radiographs, and standard laboratory tests including rheumatoid factors (RF), antiperinuclear factor (APF), antikeratin antibody (AKA), anticyclic citrullinated peptide antibody (anti-CCP), antinuclear antibodies, and HLA-AB-DR typing. After a median followup of 30 months, the diagnosis was evaluated by a hospital-based rheumatologist. RESULTS: Age and sex did not differ across the 3 groups. Knee involvement was more common in the MA group than in the MA + past group (p < 0.03), whereas hand and metatarsophalangeal involvement was less common (p < 0.03 and p < 0.0001, respectively). RF and anti-CCP were less often positive in the MA group than in the MA + past group (p < 0.02 and p < 0.001, respectively) and the OA/PA group (p < 0.02 and p < 0.03). No patient in the MA group received a diagnosis of rheumatoid arthritis (RA). RA was less common and disease modifying antirheumatic drugs were prescribed less often in the MA group than in the other 2 groups (p < 0.0001 for both comparisons). CONCLUSION: The MA group was clearly different from the other groups, with a favorable outcome and no risk of progression to RA. 相似文献