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991.
Anticocaine catalytic antibodies 总被引:5,自引:0,他引:5
Cocaine mediates its reinforcing and toxic actions through a "loss of function" effect at multiple receptors. The difficulties inherent in blocking a pleiotropic blocker pose a great obstacle for the classical receptor-antagonist approach and have contributed to the failure (to date) to devise specific treatments for cocaine overdose and addiction. As an alternative, we have embarked on an investigation of catalytic antibodies, a programmable class of artificial enzyme, as "peripheral blockers" -- agents designed to bind and degrade cocaine in the circulation before it partitions into the central nervous system to exert reinforcing or toxic effects. We synthesized transition-state analogs of cocaine's hydrolysis at its benzoyl ester, immunized mice, prepared hybridomas and developed the first anticocaine catalytic antibodies with the capacity to degrade cocaine to nonreinforcing, nontoxic products. We subsequently identified several families of anticocaine catalytic antibodies and found that the most potent antibody possessed sufficient activity to block cocaine-induced reinforcement, organ dysfunction and sudden death in rodent models of addiction, toxicity and overdose, respectively. With the potential to promote cessation of use, prolong abstinence and provide a treatment for acute overdose, the artificial enzyme approach comprehensively responds to the problem of cocaine. 相似文献
992.
OBJECTIVE: Raloxifene, a selective estrogen receptor modulator, is estrogen-like in the skeleton and cardiovascular system and antiestrogenic in reproductive tissues. In contrast to estrogens, raloxifene is not indicated for the treatment of hot flashes. This study was designed to examine the characteristics of hot flashes among healthy postmenopausal women participating in osteoporosis prevention trials who were receiving raloxifene or placebo. METHODS: Adverse event data from three randomized, double-blind trials (N = 876) comparing raloxifene 60 mg/day with placebo for 30 months were integrated and analyzed. Two of the three trials (one European, two North American) were identically designed and were open to healthy postmenopausal women ages 45 through 60 without regard to prior hysterectomy. The third trial was multinational, was open to women ages 40 through 60, and all enrollees had prior hysterectomy at baseline. Women were questioned in general terms about the occurrence of adverse events at 3-6-month intervals. Treatment-emergent adverse events pertaining to hot flashes were included in the current study. RESULTS: At baseline, 12% of women randomly assigned to placebo and 13% assigned to raloxifene reported prevalent hot flashes. After 30 months, the cumulative incidence of hot flashes was 21% for placebo and 28% for raloxifene (P = 0.022), with the difference in incidence rate confined to the first 6 months of therapy. There was no difference between placebo and raloxifene in reported maximum severity of or early discontinuations as a result of hot flashes (< or = 3% per group for both outcomes). Among women whose hot flashes had stopped completely during the 30-month study period, the median total duration of the event prior to becoming symptom-free was 246 days for placebo and 205 days for raloxifene. Among all women reporting a hot flash, the extrapolated total duration of hot flashes was the same for women treated with either raloxifene or placebo. No subgroup-by-therapy interactions were detected. Multivariable regression analysis revealed several factors that were independently weakly predictive of hot flashes. CONCLUSIONS: Raloxifene slightly affects the incidence but not the natural history of hot flashes in healthy postmenopausal women seeking prevention therapy. 相似文献
993.
Alterations in muscarinic receptor-coupled phosphoinositide hydrolysis and AP-1 activation in Alzheimer's disease cybrid cells 总被引:2,自引:0,他引:2
Alzheimer's disease cybrid cells produced by replacing endogenous mitochondria in human neuroblastoma SH-SY5Y cells with platelet mitochondria from subjects with Alzheimer's disease have higher levels of reactive oxygen species than do cybrid cells with mitochondria from control subjects. These cells were used to test if this chronic mild increase in reactive oxygen species affects muscarinic receptor-coupled signaling activities. Basal and carbachol-stimulated phosphoinositide hydrolysis were higher, and there was less inhibition by glutathione depletion, in Alzheimer's disease than control cybrid cells. Elevated phosphoinositide hydrolysis in Alzheimer's disease cybrid cells also was evident upon direct activation of G-proteins (Gq/11) linked to phosphoinositide signaling or of phospholipase C, but immunoblot analyses revealed equivalent levels of Gq/11 and phospholipase C in both cell lines. These results indicate that there is up-regulation of phosphoinositide signaling in Alzheimer's disease cybrid cells in association with chronic mild oxidative stress, although treatment of cells with H(2)O(2) to induce greater acute oxidative stress caused decreases in carbachol-stimulated phosphoinositide hydrolysis that were similar in Alzheimer's disease and control cybrid cells. In contrast to phosphoinositide hydrolysis, carbachol-stimulated AP-1 DNA binding activity was lower in Alzheimer's disease than control cybrid cells, and this deficit was associated with deficient protein kinase C-mediated activation of AP-1. Overall, these results demonstrate that chronically elevated reactive oxygen species in Alzheimer's disease cybrid cells are associated with a more robust phosphoinositide signaling system, but lower signaling to activation of AP-1. These alterations may represent adaptations to exposure to oxidants, which precede more widespread deficits in signaling associated with more severe oxidative stress. 相似文献
994.
Update on Pneumocystis carinii f. sp. hominis Typing Based on Nucleotide Sequence Variations in Internal Transcribed Spacer Regions of rRNA Genes 总被引:6,自引:0,他引:6 下载免费PDF全文
Chao-Hung Lee Jannik Helweg-Larsen Xing Tang Shaoling Jin Baozheng Li Marilyn S. Bartlett Jang-Jih Lu Bettina Lundgren Jens D. Lundgren Mats Olsson Sebastian B. Lucas Patricia Roux Antonietta Cargnel Chiara Atzori Olga Matos James W. Smith 《Journal of clinical microbiology》1998,36(3):734-741
Pneumocystis carinii f. sp. hominis isolates from 207 clinical specimens from nine countries were typed based on nucleotide sequence variations in the internal transcribed spacer regions I and II (ITS1 and ITS2, respectively) of rRNA genes. The number of ITS1 nucleotides has been revised from the previously reported 157 bp to 161 bp. Likewise, the number of ITS2 nucleotides has been changed from 177 to 192 bp. The number of ITS1 sequence types has increased from 2 to 15, and that of ITS2 has increased from 3 to 14. The 15 ITS1 sequence types are designated types A through O, and the 14 ITS2 types are named types a through n. A total of 59 types of P. carinii f. sp. hominis were found in this study. 相似文献
995.
Natural immune response to the C-terminal 19-kilodalton domain of Plasmodium falciparum merozoite surface protein 1. 总被引:5,自引:2,他引:5 下载免费PDF全文
Y P Shi U Sayed S H Qari J M Roberts V Udhayakumar A J Oloo W A Hawley D C Kaslow B L Nahlen A A Lal 《Infection and immunity》1996,64(7):2716-2723
We have characterized the natural immune responses to the 19-kDa domain of merozoite surface protein 1 in individuals from an area of western Kenya in which malaria is holoendemic. We used the three known natural variant forms of the yeast-expressed recombinant 19-kDa fragment that are referred to as the E-KNG, Q-KNG, and E-TSR antigens. T-cell proliferative responses in individuals older than 15 years and the profile of immunoglobulin G (IgG) antibody isotypes in individuals from 2 to 74 years old were determined. Positive proliferative responses to the Q-KNG antigen were observed for 54% of the individuals, and 37 and 35% of the individuals responded to the E-KNG and E-TSR constructs, respectively. Considerable heterogeneity in the T-cell proliferative responses to these three variant antigens was observed in different individuals, suggesting that the 19-kDa antigen may contain variant-specific T epitopes. Among responses of the different isotypes of the IgG antibody, IgG1 and IgG3 isotype responses were predominant, and the prevalence and levels of the responses increased with age. We also found that a higher level of IgG1 antibody response correlated with lower parasite density among young age groups, suggesting that IgG1 antibody response may play a role in protection against malaria. However, there was no correlation between the IgG3 antibody level and protection. Furthermore, we observed that although the natural antibodies cross-reacted with all three variant 19-kDa antigens, IgG3 antibodies in 12 plasma samples recognized only the E-KNG and Q-KNG constructs and not the E-TSR antigen. This result suggests that the fine specificity of IgG3 antibodies differentiates among variant-specific natural B-cell determinants in the second epidermal growth factor domain (KNG and TSR) of the antigen. 相似文献
996.
戊二醛交联甲壳胺膜的制备及其渗透性的研究 总被引:2,自引:0,他引:2
本文制备戊二醛交联甲壳胺膜。研究了戊二醛交联对膜的亲水性,结晶性的影响;探讨了交联对肌肝、尿素、尿酸的渗透;测定膜在于干态和湿态下的力学机械性能。 相似文献
997.
Previous work has found that singleton birth outcomes are better if the father is black and the mother is white than if the father is white and the mother is black. We sought to examine the effects of parental race on fetal and infant mortality in twins. We analyzed the fetal and infant mortality rates in four groups [both parents white (W-W), both parents black (B-B), father black and mother white (FB-MW), and father white and mother black (FW-MB)], using the 1995--1997 U.S. twin registry data (249,221 twins). Compared to W-W, the infant mortality for B-B, FW-MB, and FB-MW (respectively, relative risk [RR] 1.84, 95% confidence interval [CI] 1.73-1.95; RR 1.39, 95% CI 1.03-1.51; and RR 1.49, 95% CI 1.26-1.77) were all significantly different from W-W but not from each other. When fetal mortality was added to infant mortality, the combined mortality was highest for B-B (RR 1.66, 95% CI 1.58-1.75), intermediate for FW-MB (RR 1.18, 95% CI 0.92-1.51) and FB-MW (RR 1.37, 95% CI 1.19-1.58) and lowest for W-W. Thus, twin infants born to black parents have higher risk of fetal and infant mortality compared with twin infants born to white parents and infants of mixed race parents generally have intermediate outcomes. 相似文献
998.
目的 对一个中国良性家族性新生儿惊厥(benign familial neonatal convulsions,BFNC)家系进行基因诊断,并探讨其分子发病机理。方法 对该家系进行详细的临床检查及疾病基因的连锁分析。应用聚合酶链反应(polymerase chain reaction,PCR)-DNA直接测序,并用PCR-单链构象多态(single strand conformation polymorphism,SSCP)对先证者、家系内16人及家系外72名无血缘关系的正常入进行KCNQ2基因突变分析。结果 连锁分析提示该家系与KCNQ2基因连锁,并排除与KCNQ3基因连锁。PCR—DNA直接测序在先证者发现.KCNQ2基因突变193ldelG,PCR—SSCP发现家系内其他患者均出现与先证者相同的异常SSCP条带,而72名正常人未出现此异常条带。结论 KCNQ2基因突变是中国人BFNC的发病原因之一,193ldelG是国内外未曾报道过的新突变,连锁分析结合基因突变分析可对BFNC患者进行基因诊断。 相似文献
999.
西部开发中的虫媒病传播问题 总被引:1,自引:1,他引:1
陆宝麟 《寄生虫与医学昆虫学报》2003,10(4):212-217
西部开发地区存在许多虫媒病 ,即昆虫和蜱螨传播的疾病 ,为了保障开发人群的健康 ,首先需要对这些疾病的传播 ,特别是有些疾病的自然疫源地或流行区有所了解。本文列述了 13种虫媒病及其在这个地区的分布 ,对其中值得我们更重视的 4类重要疾病 ,包括鼠疫、莱姆病、疟疾和登革热的病原体传播媒介或有的贮存宿主以及重要性等作了扼要的介绍。本文并提出了这类疾病在开发中和开发后可能产生的危害性 ,以及防止或减少它们危害的建议。作者认为从开发地区的长远利益出发 ,应该重视开发中自然环境改变对上述虫媒病传播影响的研究 相似文献
1000.
Relationship between Plasma Interleukin-12 (IL-12) and IL-18 Levels and Severe Malarial Anemia in an Area of Holoendemicity in Western Kenya 下载免费PDF全文
Sujittra Chaisavaneeyakorn Caroline Othoro Ya Ping Shi Juliana Otieno Sansanee C. Chaiyaroj Altaf A. Lal Venkatachalam Udhayakumar 《Clinical and Vaccine Immunology : CVI》2003,10(3):362-366
In this study, we investigated whether levels of interleukin-12 (IL-12) and IL-18 in plasma are associated with severe malarial anemia outcomes in an area of holoendemicity in western Kenya. We compared plasma IL-12 and IL-18 levels in six groups of children grouped into the categories aparasitemic, asymptomatic, mild malaria, high-density uncomplicated malaria (UC), moderate malarial anemia (MMA), or severe malarial anemia (SMA). IL-12 levels were significantly reduced in children with SMA (P < 0.05) but not in other groups compared to children in the aparasitemic control group. IL-18, a cytokine known to be critical for the induction of gamma interferon along with IL-12, was produced more frequently (70%) in children with UC (P = 0.06) than in children in the aparasitemic control group (32%). However, in the SMA group the IL-18 response rate declined to 30%, which was similar to that in the aparasitemic control group, which showed a 32% response rate. This finding suggests that the IL-18 response may be impaired in children with SMA. In summary, the results from this study support the hypothesis that impairment of IL-12 and/or IL-18 response may contribute to the development of severe malarial anemia in areas of holoendemicity for malaria. 相似文献