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A Thalamic Contribution to Arousal-induced, Non-photic Entrainment of the Circadian Clock of the Syrian Hamster 总被引:3,自引:0,他引:3
Elizabeth S. Maywood Emma Smith Stephanie J. Hall Michael H. Hastings 《The European journal of neuroscience》1997,9(8):1739-1747
It is well established that the circadian clock of the suprachiasmatic nuclei (SCN) is entrained by light. More recently, the potent effects of arousing, non-photic cues on the clock have been recognized. The neural mediators of non-photic entrainment are yet to be identified. To examine the contribution of the thalamic intergeniculate leaflet (IGL) and its NPY-immunopositive projection, the geniculo-hypothalamic tract to non-photic entrainment by arousal, male Syrian hamsters received lesions of the IGL (IGLX) which ablated NPY-immunoreactivity in the SCN. Their circadian responses to both photic and non-photic cues were then tested. Lesions resulted in a delay in the timing of activity onset following lights out, but had no effect on the behavioural or cellular circadian responses to phase-advancing light pulses presented at circadian time (CT) CT19 (where CT12 represents the time of activity onset). Injection with a benzodiazepine (chlordiazepoxide, 100 mg/kg) at CT6 suppressed wheel-running, increased general locomotion of intact controls and induced large phase advances of the circadian rhythm of wheel-running. Chlordiazepoxide also inhibited wheel-running in lesioned animals, but there was no significant increase in general locomotion and the lesioned animals did not phase advance. Serial arousal by injection of saline at intervals of 23.5 h for 6 days entrained the circadian rhythm of wheel-running of intact hamsters and was associated with an increase in general locomotor activity. Entrainment by serial arousal was abolished by IGLX. However, the lesioned animals did show a clear behavioural response to every presentation of the non-photic cue. These results show that the IGL is a necessary component of the neural pathways mediating both arousal- and benzodiazepine-induced non-photic entrainment. 相似文献
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Elizabeth P. Eustis-Turf Joyce A. Benjamins Maurice J. Lefford 《Journal of neuroimmunology》1986,10(4):313-330
Sera from 43 leprosy patients were tested for antibodies that bound to normal human nerve. Thirty-eight percent showed positive staining as demonstrated by indirect immunofluorescence. Only 1 out of 30 control sera tested displayed similar staining. Western blots of myelin and neural intermediate filament (IF) proteins were tested with patient sera. Two of the anti-neural antibody (ANeAb)-positive leprosy sera bound to the P0 protein of PNS myelin. All 17 ANeAb-positive leprosy sera displayed 2 or more bands in the molecular weight range of Mr 45 000-55 000, when tested against IF proteins. One explanation for these findings is that leprosy patients produce antibodies to intermediate filament (IF) proteins released subsequent to the bacterial invasion of the peripheral nerves. The importance of these autoantibodies in the pathogenesis of leprosy is discussed. 相似文献
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Judith D. DePue Elizabeth L. McQuaid Daphne Koinis-Mitchell Christopher Camillo Anthony Alario Robert B. Klein 《The Journal of asthma》2007,44(6):449-453
Over 3 years, 972 families participated in an after-school asthma program at their child's school. Parents and children attended concurrent 21/2 -hour workshops. Parents were 74% Latino; 45% non-English speaking, with 77% of children on Medicaid. Asthma symptoms were significantly reduced, from multiple times per week to less than once per week on average. Oral steroid use decreased to one third of baseline use. Hospital days decreased from 11% to 2%; emergency visits decreased 35% to 4%; and school days missed decreased 48% to 20%. This program has now become sustainable with both private and Medicaid insurance coverage. 相似文献
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Elizabeth B Haagsma Ingrid I Van Gameren Johan Bijzet Marcel D Posthumus Bouke P C Hazenberg 《Amyloid》2007,14(3):221-226
To estimate the evolution of amyloid in tissue, we studied abdominal fat aspirates of cases with familial amyloidotic polyneuropathy (FAP) longitudinally at regular intervals between 1994 and 2006. In 22 cases (13 carriers and nine patients) not yet transplanted median follow-up was 3.3 years (range 0.4-11.3). We found a significant increase in the amyloid grade of fat tissue from 2+ to 4+ and from 0 to 4+ in two of three subjects with follow-ups of >7 years, after 7 and 11 years, respectively. All other subjects remained negative or did not show a significant change. In 11 liver transplant patients, follow-up with fat aspirate was available with a median duration of 3.1 years (range 1.0-10.1). A comparison was made with cardiac amyloid as judged by the cardiac septum diameter and the serum NT-ProBNP (N-terminal pro-B-type natriuretic peptide) level. No stable increase of amyloid in fat was seen in any patient. A stable decrease of amyloid grade was seen in one patient 5 years after transplantation. In contrast, the cardiac septum diameter increased >or=4 mm in six of the 11 transplant patients. Our study shows the diagnostic utility of a regularly repeated fat aspirate in carriers at risk for the development of ATTR amyloidosis. Evolution of amyloid deposition in fat tissue is very gradual. After liver transplantation, amyloid deposition in fat tissue seems to stabilize and may even decrease in the long term, whereas amyloid deposition in cardiac tissue appears to be progressive. 相似文献
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James Edward Paul Elizabeth Ling Carlos Lalonde Lehana Thabane 《Journal canadien d'anesthésie》2007,54(10):799-810
PURPOSE: To determine if deliberate hypotension decreases blood loss and transfusion requirements in patients undergoing orthopedic surgery, a systematic review of all randomized trials addressing this issue was undertaken. METHODS: Electronic databases, citations lists and review articles were searched for potential articles. Relevant articles met the following inclusion criteria: English language, humans undergoing orthopedic surgery, deliberate hypotension used by any method, intraoperative blood loss measured as an outcome, and the trial methodology being randomized and controlled. Four outcomes were analyzed, including estimated blood loss, blood transfused, surgery duration, and quality of the surgical field. For all analyses, the random-effects model was used. RESULTS: Seventeen articles met the inclusion criteria. The surgeries studied included total hip arthroplasty (seven), orthognathic surgery (eight), total knee arthroplasty (one) and spinal fusion (one). A total of 636 patients were randomized across all studies. For blood loss, the overall weighted mean difference favoured treatment, with a savings of about 287 mL of blood [95% confidence interval (CI): -447, -127]. The mean differences also showed a statistically significant benefit for deliberate hypotension in reducing transfusion requirements (-667 mL of blood transfused; 95% CI: -963, -370). Deliberate hypotension was not shown to reduce the duration of surgery (-1.9 min of surgery; 95% CI: -7.2, 3.5) or improve surgical conditions (surgical field quality rating -0.5; 95% CI: -1.1, 0.2). CONCLUSION: This review provides some support for the use of deliberate hypotension in reducing blood loss and transfusion requirements in orthopedic surgery, but these results are tempered by the small sample sizes and poor methodological quality of published studies. 相似文献