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21.
E Del Villar P Vega C Gaule E Sanchez 《European journal of drug metabolism and pharmacokinetics》1990,15(4):279-285
Short or long term diabetes in female rats produced remarkable activation of aminopyrine N-demethylation, inhibition of oestrone and p-nitrophenol glucuronidation and no changes in morphine UDP-glucuronyltransferase activity in vitro. Km and Vmax for these reactions were determined. Insulin treatment partially antagonized diabetes activation of aminopyrine N-demethylation: it restored decreased UDP-glucuronyltransferase activities for oestrone and p-nitrophenol only in long term and short term diabetes, respectively. Insulin also markedly inhibited morphine glucuronidation. Triton X-100 also displayed a differential pattern of activation for the glucuronidation reactions in liver microsomes of diabetic rats. Results suggest that diabetes in female rats may increase the actual amount of enzyme protein for aminopyrine metabolism and to decrease that for oestrone and p-nitrophenol. 相似文献
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E Esplugas A Cequier F Jara J Mauri T Soler J Sala X Sabate 《The American journal of cardiology》1991,68(10):1020-1024
Studies in vitro have suggested that nonionic low osmolar contrast agents produce an increase in thrombogenicity. To determine the incidence of thrombi related to the use of nonionic low osmolar contrast media during coronary angioplasty, a double-blind randomized study was performed in 100 patients. Medication before angioplasty included oral aspirin (250 mg/day) in all cases. At the beginning of the procedure, aspirin (250 mg) and heparin (10,000 U) were intravenously administered. During the procedure patients were randomly assigned to receive either an ionic low osmolar contrast agent ioxaglate (n = 50), or a nonionic low osmolar contrast media iohexol (n = 50). The presence of thrombus was evaluated on the angiogram and on the guidewire immediately after its retrieval from the patients. Clinical, angiographic and procedural variables were similar in the 2 randomized groups. Angiographic evidence of thrombus was observed in 1 patient (2%) assigned to ioxaglate and in 11 patients (22%) assigned to iohexol (p less than 0.005). One patient (2%) from the ioxaglate group and 6 patients (12%) from the iohexol group showed thrombotic residues on the guidewire (p = not significant). Three patients had acute myocardial infarction, 1 patient (2%) receiving ioxaglate and 2 patients (4%) iohexol (p = not significant). There were no deaths. Thus, compared with an ionic low osmolar contrast media ioxaglate, the nonionic low osmolar contrast agent iohexol increases the incidence of thrombus during coronary angioplasty. 相似文献
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25.
Maria Cabrerizo Juan E Echevarria Almudena Otero Paloma Lucas Gloria Trallero 《Journal of clinical virology》2008,43(3):323-327
BACKGROUND: Coxsackievirus A24 variant is one of the major etiological agents involved in acute haemorrhagic conjunctivitis. STUDY DESIGN: An outbreak of acute hemorrhagic conjunctivitis occurred in the Southeast of Spain between September and November 2004. Cellular and molecular methods were used to identify and characterize the viral agent associated with the epidemic. RESULTS: Enterovirus was detected in the conjunctival swabs of 35 patients. None of the viruses isolated could be typed by conventional neutralization assays; however, amplification and sequencing of the 3'-end VP1 region of 19 of the samples identified coxsackievirus A24 variant as the serotype causing the outbreak. Phylogenetic analysis of the 5'-half VP1 region of the genome revealed that Spanish sequences, like other strains isolated during outbreaks of hemorrhagic conjunctivitis in American and African countries in 2003 and 2004, were closely related to the isolates detected in Korea (2002), thus proving their worldwide spread. CONCLUSIONS: This is the first report of an epidemic of acute hemorrhagic conjunctivitis due to a coxsackievirus A24 variant in Spain. Molecular typing in combination with phylogenetic analysis is useful to study the enterovirus epidemiology associated with epidemics. 相似文献
26.
Leukemias and lymphomas are monoclonal neoplasms that arise as a result of molecular abnormalities. These abnormalites are diverse but can be grouped into two general categories, chromosomal translocations that usually result in oncogene activation and inactivation of tumor suppressor genes. Recent advances in our understanding of chromosomal translocations have led to improved classification of leukemias and lymphomas. For example, the t(9;22)(q34;q11) is now considered a defining feature of chronic myeloid leukemia, and the t(2;5)(p23;q35) defines a clinically and biologically unique subset of anaplastic large cell lymphomas. In this review, we focus on chromosomal translocations in hematologic neoplasms and the techniques used for their detection. We also briefly discuss tumor suppressor genes and assessment of clonality in lymphoid neoplasms. 相似文献
27.
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
28.
Diisocyanate asthma and gene-environment interactions with IL4RA, CD-14, and IL-13 genes. 总被引:1,自引:0,他引:1
David I Bernstein Ning Wang Paloma Campo Ranajit Chakraborty Andrew Smith André Cartier Louis-Philippe Boulet Jean-Luc Malo Berran Yucesoy Michael Luster Susan M Tarlo Gurjit K Khurana Hershey 《Annals of allergy, asthma & immunology》2006,97(6):800-806
BACKGROUND: Diisocyanate asthma (DA) affects 2% to 10% of exposed workers, yet the pathogenetic mechanisms underlying this disorder remain ill defined. OBJECTIVE: To determine if specific single nucleotide polymorphisms (SNPs) of interleukin 4 receptor alpha (IL4RA), IL-13, and CD14 promoter genes are associated with DA. METHODS: Sixty-two workers with DA confirmed by specific inhalation challenge (SIC) and 75 diisocyanate-exposed, SIC-negative workers were analyzed for SNPs associated with IL4RA, IL-13, and CD14 promoter genes. RESULTS: No associations were found with individual SNPs and DA. When stratified according to specific diisocyanate exposure, a significant association was found between IL4RA (I50V) II and DA among individuals exposed to hexamethylene diisocyanate (HDI) (odds ratio [OR], 3.29; 95% confidence interval [CI], 1.33-8.14; P = .01) only. Similarly, the IL4RA (I50V) II and IL-13 (R110Q) RR combination was significantly associated with DA in HDI-exposed workers (OR, 4.13; 95% CI, 1.35-12.68; P = .01), as was the IL4RA (I50V) II and CD14 (C159T) CT genotype combination (OR, 5.2; 95% CI, 1.82-14.88; P = .002) and the triple genotype combination IL4RA (I50V) II, IL-13 (R110Q) RR, and CD14 (C159T) CT (OR, 6.4; 95% CI, 1.57-26.12; P = .01). CONCLUSIONS: Gene-environmental interactions may contribute to the pathogenesis of DA, and gene-gene interactions may modulate this relationship. 相似文献
29.
Montano SM Sanchez JL Laguna-Torres A Cuchi P Avila MM Weissenbacher M Serra M Viñoles J Russi JC Aguayo N Galeano AH Gianella A Andrade R Arredondo A Ramirez E Acosta ME Alava A Montoya O Guevara A Manrique H Sanchez JL Lama JR de la Hoz F Sanchez GI Ayala C Pacheco ME Carrion G Chauca G Perez JJ Negrete M Russell KL Bautista CT Olson JG Watts DM Birx DL Carr JK;South American HIV Molecular Surveillance Working Group 《Journal of acquired immune deficiency syndromes (1999)》2005,40(1):57-64
HIV cross-sectional studies were conducted among high-risk populations in 9 countries of South America. Enzyme-linked immunosorbent assay screening and Western blot confirmatory testing were performed, and env heteroduplex mobility assay genotyping and DNA sequencing were performed on a subset of HIV-positive subjects. HIV prevalences were highest among men who have sex with men (MSM; 2.0%-27.8%) and were found to be associated with multiple partners, noninjection drug use (non-IDU), and sexually transmitted infections (STIs). By comparison, much lower prevalences were noted among female commercial sex workers (FCSWs; 0%-6.3%) and were associated mainly with a prior IDU and STI history. Env subtype B predominated among MSM throughout the region (more than 90% of strains), whereas env subtype F predominated among FCSWs in Argentina and male commercial sex workers in Uruguay (more than 50% of strains). A renewed effort in controlling STIs, especially among MSM groups, could significantly lessen the impact of the HIV epidemic in South America. 相似文献
30.
The presence of 5-hydroxytryptamine (5-HT)-like immunoreactivity (IR) was studied in the rat female reproductive system using polyclonal antibodies directed against 5-HT. Moreover, 5-HT levels in the ovary, oviduct, uterus, and cervix were measured by high-pressure liquid chromatography with electrochemical detection. The highest 5-HT concentrations were found in the oviduct, followed in descending order by the cervix, the ovary, and the uterus. Most 5-HT-like IR was observed in the cytoplasm of mast cells. These cells were found in the connective tissue around the fimbria, in the oviduct, in the uterus, and in the ovary. Mast cells are clustered in the proximity of the parenchymal blood vessels. Moreover, a few 5-HT-like nerve fibers were found distributed mainly perivascularily in the uterine cervix and in the uterine horns as well as in the oviduct. IR nerve fibers were rarely seen within the ovary. The present data provide direct evidence that 5-HT in the female reproductive system not only is associated with mast cells but is located in nerve fibre-like structures as well. The functional significance of this probable 5-HT-ergic innervation of the female reproductive tract discovered in the present study should be clarified in future investigations. 相似文献