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Fatty acid amides (FAAs) represent a class of neuromodulatory lipids that includes the endocannabinoid anandamide and the sleep-inducing substance oleamide. Both anandamide and oleamide produce behavioral effects indicative of cannabinoid activity, but only anandamide binds the cannabinoid (CB1) receptor in vitro. Accordingly, oleamide has been proposed to induce its behavioral effects by serving as a competitive substrate for the brain enzyme fatty acid amide hydrolase (FAAH) and inhibiting the degradation of endogenous anandamide. To test the role that FAAH plays as a mediator of oleamide activity in vivo, we have compared the behavioral effects of this FAA in FAAH(+/+) and (-/-) mice. In both genotypes, oleamide produced hypomotility, hypothermia, and ptosis, all of which were enhanced in FAAH(-/-) mice, were unaffected by the CB1 antagonist N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-di-chlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide hydrochloride (SR141716A) and occurred in CB1(-/-) mice. Additionally, oleamide displayed negligible binding to the CB1 receptor in brain extracts from either FAAH(+/+) or (-/-) mice. In contrast, anandamide exhibited a 15-fold increase in apparent affinity for the CB1 receptor in brains from FAAH(-/-) mice, consistent with its pronounced CB1-dependent behavioral effects in these animals. Contrary to both oleamide and anandamide, monoacylglycerol lipids exhibited equivalent hydrolytic stability and pharmacological activity in FAAH(+/+) and (-/-) mice. Collectively, these results indicate that FAAH is a key regulator, but not mediator of FAA activity in vivo. More generally, these findings suggest that FAAs represent a family of signaling lipids that, despite sharing similar chemical structures and a common pathway for catabolism, produce their behavioral effects through distinct receptor systems in vivo.  相似文献   
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Chromosome 7q21-22 and, in particular, the region surrounding D7S554 emerged from the recent American genome screen in multiple sclerosis (MS) as the most promising region genome-wide for harboring a disease susceptibility gene. We tested association between D7S554 and MS in 217 Sardinian trio MS families by the transmission disequilibrium test (TDT), and in a Northern Irish case-control study comprising 542 individuals. In both populations, we found evidence for significant allelic association (P(c)=0.04 and P(c)=0.0002, respectively). In a second stage, we analysed five microsatellite markers in a 4 megabase interval on chromosome 7q21-22 in the same set of Sardinian families. Parental transmission of a single allele of one of these markers, i.e. D7S3126, was significantly distorted (P(c)=0.008). D7S554 and D7S3126 are located at distances of, respectively, 40 and 81 kb 5' from the startcodon of the protachykinin-1 gene (TAC1), and occur in strong linkage disequilibrium (P<10(-7)). Our study indicates that the previous finding of linkage with D7S554 refers possibly to the presence of an MS susceptibility effect in vicinity to TAC1. In addition, a second independent association was uncovered between a microsatellite polymorphism in the plasminogen activator inhibitor-1 gene, i.e. D7S477, and MS. Overall, the analysis presented here may contribute to the increasingly refined genomic map of MS and underscores the requirement for a further high-resolution screening of chromosome 7q21-22.  相似文献   
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Current treatments for metastatic breast cancer are not associated with significant survival benefits despite response rates of over 50%. High-dose therapy with autologous bone marrow transplantation (ABMT) has been investigated, particularly in North America, and prolonged survival in up to 25% of women has been reported, but with a significant treatment-related mortality. However, in patients with haematological malignancies undergoing autologous transplantation, haematopoietic reconstruction is significantly quicker and mortality lower than with ABMT, when peripheral blood progenitor cells (PBPCs) are used. In 32 women with metastatic breast cancer, we investigated the feasibility of PBPC mobilisation with high-dose cyclophosphamide and granulocyte colony-stimulating factor (G-CSF) after 12 weeks'' infusional induction chemotherapy and the subsequent efficacy of the haematopoietic reconstitution after conditioning with melphalan and either etoposide or thiotepa. PBPC mobilisation was successful in 28/32 (88%) patients, and there was a rapid post-transplantation haematopoietic recovery: median time to neutrophils > 0.5 x 10(9) l-1 was 14 days and to platelets > 20 x 10(9) l-1 was 10 days. There was no procedure-related mortality, and the major morbidity was mucositis (WHO grade 3-4) in 18/32 patients (56%). In a patient group of which the majority had very poor prognostic features, the median survival from start of induction chemotherapy was 15 months. Thus, PBPC mobilisation and support of high-dose chemotherapy is feasible after infusional induction chemotherapy for patients with metastatic breast cancer, although the optimum drug combination has not yet been determined.  相似文献   
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A recombinant chimeric Fab (rcFab), with Fv derived from the monoclonal A5B7 antibody to carcinoembryonic antigen (CEA), and with human CHI and Ck was cloned into pUC 19 and expressed in Escherichia coli. rcFab (10 to 12 mg per litre) was produced in bacterial culture fluid, and functional purified rcFab was isolated by affinity chromatography (using antibody to human Ck) and size-exclusion gel filtration. The re Fab did not show reduced affinity for CEA, and reacted with human colorec-tal tumours showing a typical anti-CEA pattern by immunocyto-chemistry; it was also stable after iodination. Biodistribution studies in nude mice bearing human tumour xenografts showed no toxicity and good turnout- localization. Therapeutic ratios at early time points were better than those obtained with whole murine antibody. The results demonstrate that bacterial I y produced anti-CEA Fab is of use for tumour targeting. © Wiley-Liss, Inc.  相似文献   
77.
Microvascular changes in large flame burn wound in sheep   总被引:1,自引:0,他引:1  
Advances in local wound management with early excisional therapy have decreased morbidity and mortality of massive third-degree burn patients. Although blood redistribution within burned tissue is of clinical interest, few studies have longitudinally determined the regional blood flow of various layers of the burn wound. We used a conscious ovine model in which animals were subjected to 40% third degree burn. Burned tissue was divided into the four layers (i.e. skin, panniculus carnosus, adipose tissue, and skeletal muscle), and regional blood flow was determined separately, with fluorescent microspheres, while measuring systemic hemodynamics and total burned tissue microvascular fluid flux. The subburn adipose tissue exhibited a remarkable biphasic alteration in regional blood flow, whereas the skin layer showed only decreased blood flow during the whole experimental period. The increase in blood flow to the adipose tissue seems to be related to a sustained fluid filtrate in the postresuscitation period, resulting in edema formation mainly located in the adipose tissue at the endpoint.  相似文献   
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BACKGROUND: Heel-height difference has been used to detect subtle knee flexion contractures, but the effects of thigh circumference differences and patient positioning during testing have not been evaluated. HYPOTHESIS: Differences in thigh circumference measurements and whether the patient's patellae are on or off the examination table during heel-height difference measurement will not affect the accuracy of detecting knee flexion contracture. STUDY DESIGN: Prospective cohort study. METHODS: Bilateral knee range of motion, prone heel-height difference with the patellae on and off the table, and thigh circumference at 5 and 15 cm proximal to the proximal pole of the patella were measured by one investigator on 50 consecutive patients who had undergone unilateral anterior cruciate ligament reconstruction. RESULTS: A high degree of correlation was demonstrated between the heel-height difference and the standard range of motion measurement. Differences in thigh girth and patellar position did not statistically affect the accuracy of the heel-height difference as an indicator of knee flexion contracture. CONCLUSION: Heel-height difference is a valid method of documenting knee flexion contractures. Compared with traditional goniometer assessment, this test is a more meaningful and easier way for detecting subtle knee flexion contractures of less than 10 degrees.  相似文献   
80.
BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function.  相似文献   
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