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91.
Kimmel SR 《American family physician》2005,72(10):2049-2056
Invasive disease caused by Neisseria meningitidis has an average annual incidence of one case per 100,000 in the United States. The disease can be rapidly fatal or result in severe neurologic and vascular sequelae despite antibiotic therapy. Antibiotic chemoprophylaxis with rifampin, ciprofloxacin, or ceftriaxone is required for household and other close contacts. Although the majority of cases of meningococcal disease are sporadic, outbreaks can occur, and vaccination of the affected population often is necessary. Serogroup B accounts for the highest incidence of disease in young infants but is not contained in any vaccine licensed in the United States. Adolescents and young adults 15 to 24 years of age have a higher incidence of disease and a higher fatality rate than other populations. Because 70 to 80 percent of these infections in the United States are caused by meningococcal serogroups C, Y, and W-135, which are contained in the tetravalent meningococcal vaccines, they are potentially preventable. The U.S. Food and Drug Administration recently approved a meningococcal conjugate vaccine containing serogroups A, C, Y, and W-135. This T-cell-dependent vaccine induces bactericidal antibody production and promotes immunologic memory that should result in a longer duration of immunity. The Advisory Committee on Immunization Practices recommends that this vaccine be given to 11- and 12-year-old adolescents, to adolescents entering high school, and to college freshmen living in dormitories. The vaccine also may be given to persons 11 to 55 years of age who belong to certain high-risk groups. 相似文献
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94.
Wilcox KM Kimmel HL Lindsey KP Votaw JR Goodman MM Howell LL 《Synapse (New York, N.Y.)》2005,58(4):220-228
Dopaminergic mechanisms are thought to play a central role in the reinforcing effects of cocaine. Similar to cocaine, other local anesthetics bind to the dopamine transporter (DAT) and inhibit DA uptake in rodent and monkey brain. Additionally, local anesthetics are self-administered in rhesus monkeys, indicative of abuse liability. The present study examined the reinforcing and DAT effects of the local anesthetics dimethocaine, procaine and cocaine using in vivo techniques. Monkeys were trained to respond under a second-order schedule for i.v. cocaine administration (0.10 or 0.30 mg/kg/infusion). When responding was stable, dimethocaine (0.030-1.7 mg/kg/ infusion) or procaine (0.10-10 mg/kg/ infusion) was substituted for the cocaine training dose. Dimethocaine administration produced higher response rates compared with that of procaine, and was a more potent reinforcer. Drug effects on behavior were related to DAT occupancy in monkey striatum during neuroimaging with positron emission tomography (PET). DAT occupancy was determined by displacement of 8-(2-[(18)F]fluroethyl)2beta-carbomethoxy-3beta-(4-chlorophenyl)nortropane (FECNT). DAT occupancy was between 66 and 82% and <10-41% for doses of dimethocaine and procaine that maintained maximum response rates, respectively. Finally, in vivo microdialysis in awake subjects determined drug-induced changes in extracellular DA in the caudate nucleus. There was close correspondence between peak increases in DA and DAT occupancy. Overall, reinforcing effects were consistent with DAT effects determined with in vivo techniques. The results further support a role for the DAT in the abuse liability of local anesthetics. 相似文献
95.
Kimmel RJ Kovacs I Vrabel C Wood B Schalling M Kelsoe JR 《The American journal of psychiatry》2005,162(10):1972-1974
OBJECTIVE: The authors report a large family in which bipolar disorder appears to cosegregate with autosomal-dominant medullary cystic kidney disease. METHOD: Information regarding diagnostic criteria for bipolar disorder and medullary cystic kidney disease were gathered from family members through formal research interviews, hospital admission records, imaging reports, and laboratory data. RESULTS: Of the seven members with medullary cystic kidney disease, five had bipolar I disorder, one had unipolar depression, and one had a hyperthymic phenotype. Information was not available on two members. CONCLUSIONS: The cosegregation in this family suggests a close proximity between genes for the two disorders. The two known loci of medullary cystic kidney disease are in regions of chromosomes 1 and 16 that have been previously linked to bipolar disorder and schizophrenia. This family may be a useful resource for positional cloning of bipolar candidate genes. 相似文献
96.
Chemotactic cells, including neutrophils and Dictyostelium discoideum, orient and move directionally in very shallow chemical gradients. As cells polarize, distinct structural and signaling components become spatially constrained to the leading edge or rear of the cell. It has been suggested that complex feedback loops that function downstream of receptor signaling integrate activating and inhibiting pathways to establish cell polarity within such gradients. Much effort has focused on defining activating pathways, whereas inhibitory networks have remained largely unexplored. We have identified a novel signaling function in Dictyostelium involving a Galpha subunit (Galpha9) that antagonizes broad chemotactic response. Mechanistically, Galpha9 functions rapidly following receptor stimulation to negatively regulate PI3K/PTEN, adenylyl cyclase, and guanylyl cyclase pathways. The coordinated activation of these pathways is required to establish the asymmetric mobilization of actin and myosin that typifies polarity and ultimately directs chemotaxis. Most dramatically, cells lacking Galpha9 have extended PI(3,4,5)P(3), cAMP, and cGMP responses and are hyperpolarized. In contrast, cells expressing constitutively activated Galpha9 exhibit a reciprocal phenotype. Their second message pathways are attenuated, and they have lost the ability to suppress lateral pseudopod formation. Potentially, functionally similar Galpha-mediated inhibitory signaling may exist in other eukaryotic cells to regulate chemoattractant response. 相似文献
97.
SR Mehta VSM HRA Prabhu AJ Swamy Harinder Dhaliwal Dinesh Prasad 《Medical Journal Armed Forces India》2004,60(1):25-27
The varied clinical manifestations and management of 14 male patients with delirium tremens (DT) have been studied. Eight patients were initially hospitalised for diseases unrelated to ethanol abuse i.e. 2 each for gun shot wound, myocardial infarction and stroke, and one each for pneumonia and gastroenteritis. One patient was going through withdrawal because of prodrome of viral hepatitis before he was hospitalised for uncontrolled agitation and delirium. Two known cases of mild essential hypertension on dietary therapy reported for agitation, abnormal behaviour, a single episode of tonic clonic seizure and hypertensive encephalopathy as they could not/did not get alcohol for 3 days. Three patients presented denovo with DT without concomitant illness. The other features besides delirium and hallucinations were tremulousness in 10, tachycardia in 12, fever in 3, diaphoresis in 2 and tonic clonic seizures in 4 patients. The symptoms fluctuated markedly at short intervals and 2 patients did not have any features of sympathetic overactivity. Altered hepatic biochemical parameters and ketonuria with normal blood sugar were noted in 4 and one patients respectively. Other biochemical parameters including serum electrolytes were normal. CT scan brain done for 5 patients revealed subdural haematoma in one. Cerebro spinal fluid (CSF) and EEG findings were noncontributory. All made good recovery with heavy doses of intravenous vitamin B complex, glucose and oral benzodiazepine. Short course of haloperidol was used in 2 patients. Two patients developed pancreatitis during follow up. All patients made complete recovery, and 8 patients have been followed for 8 to 12 months without relapse. The reason for hospitalisation in such cases is often unrelated to alcohol abuse; hence a detailed history of alcoholism is mandatory to identify those at risk as well as for prompt treatment and decreasing the mortality.Key Words: Alcohol withdrawal, Concomitant illnesses, Delirium, Precipitating events 相似文献
98.
Coleman PJ Brashear KM Askew BC Hutchinson JH McVean CA Duong le T Feuston BP Fernandez-Metzler C Gentile MA Hartman GD Kimmel DB Leu CT Lipfert L Merkle K Pennypacker B Prueksaritanont T Rodan GA Wesolowski GA Rodan SB Duggan ME 《Journal of medicinal chemistry》2004,47(20):4829-4837
3-(S)-Pyrimidin-5-yl-9-(5,6,7,8-tetrahydro-[1,8]naphthyridin-2-yl)-nonanoic acid (5e) and 3-(S)-(methylpyrimidin-5-yl)-9-(5,6,7,8-tetrahydro-[1,8]naphthyridin-2-yl)-nonanoic acid (5f) were identified as potent and selective antagonists of the alpha(v)beta(3) receptor. These compounds have excellent in vitro profiles (IC(50) = 0.07 and 0.08 nM, respectively), significant unbound fractions in human plasma (6 and 4%), and good pharmacokinetics in rat, dog, and rhesus monkey. On the basis of the efficacy shown in an in vivo model of bone turnover following once-daily oral administration, these two compounds were selected for clinical development for the treatment of osteoporosis. 相似文献
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100.
Ultrasound irradiation and hyperosmotic treatments were compared as facilitators of antigen (BSA) penetration through the skin by bath vaccination and as enhancers of the antibody response in goldfish. The kinetics of BSA penetration and accumulation into the skin, and via it to the blood, and the consequent specific stimulation of the humoral immune response, were studied. The main findings are: (1). ultrasonic treatment is more effective than hyperosmotic treatment in enhancing both antigen transport through the skin and antibody production; (2). the requirements for high antigen concentrations, which are needed for simple bath immersion, could be reduced five times in presonicated fish; and (3). anesthesia, which significantly reduced gill uptake following hyperosmotic treatment, had no effect on skin uptake. The importance of these finding for mass vaccination of adult fish and larvae is discussed. 相似文献