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Vinay Puri Andrew McQuillin Khalid Choudhury Susmita Datta Jonathan Pimm Srinivasa Thirumalai Robert Krasucki Jacob Lawrence Digby Quested Nicholas Bass Helen Moorey Jenny Morgan Bhaskar Punukollu Gomathinayagam Kandasami David Curtis Hugh Gurling 《Neuropsychopharmacology》2007,61(7):873-879
BACKGROUND: Linkage studies by us and others have confirmed that chromosome 1q23.3 is a susceptibility locus for schizophrenia. Based on this information, several research groups have published evidence that markers within both the RGS4 and CAPON genes, which are 700 kb apart, independently showed allelic association with schizophrenia. Tests of allelic association with both of these genes in our case control sample were negative. Therefore, we carried out further fine mapping between the RGS4 and CAPON genes. METHODS: Twenty-nine SNP and microsatellite markers in the 1q23.3 region were genotyped in the United Kingdom based sample of 450 cases and 450 supernormal control subjects. RESULTS: We detected positive allelic association after the eighth marker was genotyped and found that three microsatellite markers (p = .011, p = .014, p = .049) and two SNPs (p = .004, p = .043) localized in the 700 kb region between the RGS4 and CAPON genes, within the UHMK1 gene, were associated with schizophrenia. Tests of significance for marker rs10494370 remained significant following Bonferroni correction (alpha = .006) for multiple tests. Tests of haplotypic association were also significant for UHMK1 (p = .009) using empirical permutation tests, which make it unnecessary to further correct for both multiple alleles and multiple markers. CONCLUSIONS: These results provide preliminary evidence that the UHMK1 gene increases susceptibility to schizophrenia. Further confirmation in adequately powered samples is needed. UHMK1 is a serine threonine kinase nuclear protein and is highly expressed in regions of the brain implicated in schizophrenia. 相似文献
24.
Early detection of colorectal cancer by quantitative fluorescence image analysis of exfoliated cells
P F McGowan R E Hurst R A Bass G P Hemstreet M M Lane E Zompa C K Murray R G Postier 《American journal of surgery》1990,159(1):172-6; discussion 176-7
Early-stage colorectal cancer is potentially curable. In the present study, we applied quantitative fluorescence image analysis (QFIA) cytology to the detection of experimental colorectal cancer in a rodent model. QFIA cytology combines visual cytologic examination with quantitation of DNA content in single exfoliated cells. Cancer was induced by treating 110 rats with subcutaneous 1,2-dimethylhydrazine. Sequential colon washes were obtained weekly from each animal for 20 weeks. Control animals were treated identically except for the administration of carcinogen. Cells that were cytologically abnormal or had increased DNA content were found starting in the second week. By the eighth week, roughly 50 percent of animals had positive results, and this level remained approximately constant for the duration of the study. Tissue pathologic results were normal during weeks 1 to 7. Dysplasias became common during weeks 8 to 15 whereas most cancers appeared during weeks 16 to 21. These results indicate that QFIA cytology is a highly sensitive method for detecting even preneoplastic changes resulting from carcinogen administration and may prove useful in detecting human colorectal cancer. 相似文献
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Andres A; Morales JM; Praga M; Campo C; Lahera V; Garcia-Robles R; Rodicio JL; Ruilope LM 《Nephrology, dialysis, transplantation》1997,12(7):1437-1440
BACKGROUND: Cyclosporin has been shown to facilitate renal vasoconstriction
and to have an antinatriuretic effect. The existence of an interference of
cyclosporin with the vasodilating properties of endothelium mediated by
nitric oxide production could mediate these effects. On the other hand, the
infusion of the nitric oxide precursor L-arginine has been shown to induce
renal vasodilatation and to facilitate natriuresis in normal volunteers. We
have investigated the renal effects of the administration of an infusion of
L-arginine in renal transplant patients chronically treated with
cyclosporin. To facilitate the analysis of the data the effects of the
administration of a similar dose of cyclosporin on renal function during
the infusion of a vehicle were also investigated during the administration
of a vehicle of L-arginine. DESIGN: Ten male renal transplant patients,
chronically treated with cyclosporin and with a stable renal function were
studied during 2 consecutive days after the administration of the usual
morning dose of cyclosporin. The first day they received an intravenous
infusion of vehicle and the second the infusion of graded doses of
L-arginine (50, 100, 150 mg/kg/h) during 3 consecutive h. RESULTS: The
first day, after cyclosporin administration a significant fall (P <
0.01) was observed in natriuresis and kaliuresis in the absence of changes
in renal plasma flow and glomerular filtration rate. After the
administration of L-arginine significant (P < 0.01) increases of renal
plasma flow, glomerular filtration rate, and natriuresis were seen. The
increase in blood levels of cyclosporin after its administration did not
differ between days 1 and 2. CONCLUSION: These results indicate that
L-arginine facilitates renal vasodilatation and natriuresis in renal
transplant patients. Furthermore, the observed increase in sodium excretion
could indicate that L-arginine counteracts the antinatriuretic effect of
cyclosporin.
相似文献
27.
D L Renfrew S H Bass M A Albanese B M Whitis 《AJR. American journal of roentgenology》1992,158(3):669-672
We describe a computer version of the Index for Radiological Diagnoses of the American College of Radiology (ACR). This system combines a graphics interface with a search mechanism while preserving the hierarchical structure of the Index. The graphics interface allows easy selection of an anatomic part, while the search mechanism provides the code numbers associated with an entered term. The computer system and the paperback version of the ACR Index were compared by having 52 volunteers (21 radiology faculty members, 21 radiology residents, and 10 medical students) each code 30 cases with the book and a matched set of 30 cases with the computer. The average time to code cases was shorter when the computer was used (52.2 vs 64.5 sec; p less than .0001). Accuracy was higher when the computer was used (96.4% vs 90.4%; p less than .0001). The average confidence in the computer diagnosis was also higher (9.73 vs 9.51, on a scale of 1-10; p = .0016). This system demonstrates the ability of a computer program to outperform an analogous noncomputerized system. 相似文献
28.
Cypress (Cupressus sempervirens) pollen allergens: identification by protein blotting and improved detection of specific IgE antibodies 总被引:2,自引:0,他引:2
S A Ford B A Baldo R Panzani D Bass 《International archives of allergy and applied immunology》1991,95(2-3):178-183
On the basis of results of an investigation of the effects of different treatments employed, a dialysed and reduced extract of Cupressus sempervirens was separated electrophoretically on sodium dodecylsulphate-polyacrylamide gels before being transferred and then fixed with glutaraldehyde to nitrocellulose membrane. Probing with sera from 91 subjects allergic to C. sempervirens pollen followed by detection of bound IgE antibodies with [125I]-labelled anti-human IgE revealed 17 IgE-binding proteins in the molecular weight range 14-96 kilodaltons (kDa). One component, of molecular weight approximately 42 kDa, reacted with IgE antibodies in the sera of 81.3% of the allergic subjects and, for each of the subjects, this component bound the greatest quantity of IgE. Almost 50% of the sera recognized only the approximately 42 kDa component, reinforcing the conclusion that this component is the major allergen of C. sempervirens pollen. A comparative study employing C. sempervirens pollen allergen discs prepared commercially or in the laboratory showed that values of the uptakes of [125I]-anti-IgE indicating the presence of pollen-reactive IgE antibodies obtained with the latter discs were consistently higher (means 4.5 vs. 0.88), and that false-negative results were obtained when many sera were used with the commercial discs. The results of this study provide an essential basis for the production of standardized, safe and effective C. sempervirens pollen extract applicable to diagnosis and therapy of cypress pollen allergy. 相似文献
29.
HU-211 is a synthetic, non-psychotropic cannabinoid which acts as a non-competitive NMDA antagonist and antioxidant. We studied the drug's therapeutic window as well as its long-term effect on cognitive and motor functions in a model of closed head injury (CHI) in the rat. A weight-drop device was used to induce CHI in ether anesthetized male rats. HU-211 (5 mg/kg) was administered i.v. to the experimental groups. For the therapeutic window study, drug was injected at 4 or 6 h after CHI. Edema (water content) and clinical status (neurological severity score, NSS) were evaluated at 24 h. Reduction of edema was slight, whereas improvement of NSS was significant when the drug was administered at 4 or 6 h (P = 0.0023and0.059, respectively). To determine the drug's long-term effect, it was administered 1 h after CHI and additional doses were later given. NSS was evaluated for a period of 30 d. A single dose of HU-211 given 1 h post-CHI improved the clinical outcome during the 30 d period (P < 0.01). Repetitive doses of HU-211 injected during the post traumatic period had similar effects. Cognitive functions were evaluated in the Morris water maze, with rats trained either before or after CHI. CHI resulted in a highly significant impairment of these abilities, whereas HU-211 treatment 1 h after CHI improved performance. Our results indicate that HU-211 is a potent cerebroprotective agent, with a therapeutic window of about 4 h. The beneficial response obtained even after a single dose was long lasting, and ameliorated impairment of both motor and cognitive functions following CHI. 相似文献
30.
Does altered biomechanics cause marrow edema? 总被引:21,自引:0,他引:21