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991.
Role for M5 muscarinic acetylcholine receptors in cocaine addiction   总被引:4,自引:0,他引:4  
Muscarinic cholinergic receptors of the M5 subtype are expressed by dopamine-containing neurons of the ventral tegmentum. These M5 receptors modulate the activity of midbrain dopaminergic neurons, which play an important role in mediating reinforcing properties of abused psychostimulants like cocaine. The potential role of M5 receptors in the reinforcing effects of cocaine was investigated using M5 receptor-deficient mice in a model of acute cocaine self-administration. The M5-deficient mice self-administered cocaine at a significantly lower rate than wild-type controls. In the conditioned place preference procedure, a classic test for evaluating the rewarding properties of drugs, M5-deficient mice spent significantly less time in the cocaine-paired compartment than control mice. Moreover, the severity of the cocaine withdrawal syndrome (withdrawal-associated anxiety measured in the elevated plus-maze) was significantly attenuated in mice lacking the M5 receptor. These results demonstrate that M5 receptors play an important role in mediating both cocaine-associated reinforcement and withdrawal.  相似文献   
992.
Adult ganglionic peripheral neurons have lost dependence on target-derived neurotrophin signaling for survival and regeneration after injury. To understand the mechanisms required to sustain such processes at maturity, we are studying neuronal survival and axonal outgrowth of adult mouse dorsal root ganglia (DRG) explants. We have here examined the role of phosphatidylinositol 3-kinase (PI3-K) activity. Both neuronal survival and axonal outgrowth of spontaneously growing preparations were decreased significantly by the PI3-K inhibitor LY294002 as was the increased outgrowth caused by nerve growth factor or glial cell line-derived factor. Inhibition of PI3-K activity promoted neuronal cell death to the same extent in the presence as in the absence of a growth factor, whereas inhibition of mitogen-activated protein kinase, MAPK, lacked effect. Using a compartmentalized system, it could be shown that only axonal outgrowth was decreased when the outgrowth region only was exposed to LY294002. Already-formed growth cones showed morphological changes within 5-10 min after exposure to LY294002. Akt (PKB) is one downstream effector of PI3-K. Immunofluorescence revealed the presence of activated Akt in DRG cell bodies and in axonal growth cones. Immunoreactivity was decreased by PI3-K inhibition. The results suggest that Akt is constitutively active in adult DRG neurons, and that PI3-K mediated processes are involved in neuronal survival of one or more DRG neuronal subpopulations and also in axonal elongation. The possible significance of Akt signaling for these effects is discussed.  相似文献   
993.
OBJECTIVE: To study factors of importance for participation in parental education within routine child health care. DESIGN: All parents of children born during 1 year were invited by the district nurse to participate in parental education; their participation during the infant year was registered. SETTING: Catchment area of two health centres in V?xj?, Sweden. SUBJECTS: 221 infants and their parents. MAIN OUTCOME MEASURES: Number of educational sessions for mothers and fathers. RESULTS: 63% of mothers and 20% of fathers attended at least one session. These mothers attended a mean of 5.7 (SD 2.2) sessions and these fathers a mean of 2.8 (SD 2.3) sessions. Logistic regression analyses showed that the only variable of significance for participation was being a first-time parent (odds ratio 3.9 for the mothers and 3.7 for the fathers). Odds ratios above 2.0 (non-significant) were found for married mothers and Swedish mothers, as well as for Swedish fathers. CONCLUSION: It is still a considerable problem to get certain groups involved in routine parental education in Swedish child healthcare programmes.  相似文献   
994.
995.
We reviewed 141 cases of paranasal sinus tumors treated at Karolinska Hospital from 1960 to 1980. Of these tumors, 100 were located in the maxillary sinus, 32 in the ethmoidal sinuses, 8 in both the ethmoidal and maxillary regions, and 1 in the sphenoidal sinus. The male-to-female ratio was 2.1 to 1. Squamous cell carcinoma and adenocarcinoma were the most frequent types of tumors (55% and 13%, respectively). Treatment included surgery, irradiation, or both. The 5-year survival rate was 34% for squamous cell carcinomas and 64% for adenocarcinomas. When compared to a previous material of patients treated at the same hospital from 1940 to 1950, the proportion of poorly differentiated squamous cell carcinomas had increased significantly. The age-adjusted incidence rate decreased from 1.2 to 0.4 for male patients and from 0.7 to 0.3 for female patients between 1960 and 1980. We conclude that the incidence of malignant paranasal sinus tumors has decreased, and that squamous cell tumors now seem to be generally less differentiated than they were 50 years ago.  相似文献   
996.
Mental disorders are internationally responsible for significant disease burden and disability. However, limited cross-culturally comparisons, related to psychiatric-mental health nurses and the care they deliver, have been conducted. Therefore, the purpose of this article is to present information obtained from nurse faculty from Australia, Hong Kong, Japan, South Korea, Thailand and the USA (State of Hawaii) about: a) titles and educational preparation of the psychiatric-mental health nurses; b) the role and perception of others about the psychiatric-mental health nurses; c) nursing behavioral interventions, including medications; d) length of stay of hospitalized psychiatric patients; e) leading mental health problems; and, f) the profile of the population with a mental illness. The findings reflect diversity in the role and educational preparation of psychiatric-mental health nurses, as well as how psychiatric-mental health patients are treated.  相似文献   
997.
A number of studies have reported on the successful use of intravenous glycoprotein IIb/IIIa receptor antagonists in patients with unstable angina or undergoing percutaneous interventions. The promise of interrupting the aggregation of platelets in the setting of unstable plaques on a chronic basis had led to the evaluation of several oral agents for longer-term administration. The development program of two of these agents, xemilofiban and orbofiban, will be reviewed and evaluated to understand the selection process of therapeutic targets for use based upon complex pharmacokinetic and pharmacodynamic responses. A review of the pivotal phase III trial results will also be provided along with insights into the potential reasons for the lack of significant benefit shown with these agents to date.  相似文献   
998.
Germline mutations of the MEN1 gene have been identified as the causative genetic defect of multiple endocrine neoplasia type I (MEN-I), an autosomal dominantly inherited condition. To establish the basis for predictive family screening we evaluated the spectrum of MEN1 gene mutations in MEN-I patients treated at our institution. Relatives at risk were subjected to predictive genetic screening after genetic counseling. Gene carriers were subjected to extensive clinical screening for MEN-I, including biochemical tests for basal hormone concentrations in blood and urine, a standardized meal stimulation test and imaging procedures (ultrasonography, computed tomography, magnetic resonance imaging). Among index patients of 15 independent MEN-I kindreds, 14 heterozygous MEN1 germline mutations were identified by single-strand conformational variant analysis (SSCV) and direct DNA sequence analysis. Of 51 individuals at risk, 26 predictively tested relatives with the wild-type MEN1 gene could be excluded from further screening procedures because they had not inherited the disease. In all previously presumed unaffected relatives with the mutant gene, our extensive clinical screening program revealed at least one manifestation of MEN-I. Furthermore, 22 additional diagnoses could be established in identified MEN-I patients. We show that mutation analysis enables predictive genetic screening for MEN-I families, providing a valuable tool for genetic counseling and clinical management. An extensive clinical screening program focusing on genetically proven individuals at risk allows detection of MEN-I manifestations at an early, asymptomatic stage of the disease. Controlled, prospective studies are now required to prove whether timely appropriate treatment on the basis of predictive screening might help improve disease-related quality of life and prolong life expectancy in MEN-I kindreds.  相似文献   
999.
Mercapturic acids are N-acetyl-L-cysteine S-conjugates that are formed from a range of endogenous and exogenous chemicals. Although the kidney is a major site for elimination of mercapturic acids, the transport mechanisms involved have not been identified. The present study examined whether mercapturic acids are substrates for the renal basolateral organic anion transporter-1 (Oat1) from rat kidney. This carrier mediates uptake of organic anions from the bloodstream in exchange for intracellular alpha-ketoglutarate. Uptake of [(3)H]p-aminohippuric acid (PAH) in Oat1-expressing Xenopus laevis oocytes was strongly inhibited by S-(2,4-dinitrophenyl)-N-acetyl-L-cysteine (DNP-NAC) and by all other mercapturic acids tested, including the endogenous mercapturic acid N-acetyl-leukotriene E(4). Inhibition by the mercapturic acids was competitive, which is consistent with the hypothesis that these compounds are substrates for Oat1. This conclusion was supported by the direct demonstration of saturable [(35)S]DNP-NAC uptake in Oat1-expressing oocytes. [(35)S]DNP-NAC uptake was inhibited by PAH and other mercapturic acids and was stimulated in oocytes preloaded with glutarate. The apparent K(m) value for DNP-NAC uptake was only 2 microM, indicating that this mercapturic acid is a high affinity substrate for Oat1. Together, these data indicate that clearance of endogenous mercapturic acids is an important function of the renal organic anion transporter.  相似文献   
1000.
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