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61.
Green EK Priestley MD Waters J Maliszewska C Latif F Maher ER 《Journal of medical genetics》2000,37(8):581-587
Distal deletion of chromosome 3p25-pter (3p− syndrome) produces a distinct clinical syndrome characterised by low birth weight, mental retardation, telecanthus, ptosis, and micrognathia. Congenital heart disease (CHD), typically atrioventricular septal defect (AVSD), occurs in about a third of patients. In total, approximately 25 cases of 3p− syndrome have been reported world wide. We previously analysed five cases and showed that (1) the 3p25-pter deletions were variable and (2) the presence of CHD correlated with the proximal extent of the deletion, mapping a CHD gene centromeric to D3S18. To define the molecular pathology of the 3p− syndrome further, we have now proceeded to analyse the deletion region in a total of 10 patients (five with CHD), using a combination of FISH analysis and polymorphic markers, for up to 21 loci from 3p25-p26. These additional investigations further supported the location of an AVSD locus within 3p25 and refined its localisation. Thus, the critical region was reduced to an interval between D3S1263 and D3S3594. Candidate 3p25 CHD genes, such as PMCA2 (ATP2B2), fibulin 2, TIMP4, and Sec13R, were shown to map outside the target interval. Additionally, the critical region for the phenotypic features of the 3p− phenotype was mapped to D3S1317 to D3S17 (19-21 cM). These findings will accelerate the identification of the 3p25 CHD susceptibility locus and facilitate investigations of the role of this locus in non-syndromic AVSDs, which are a common form of familial and isolated CHD.
Keywords: congenital heart disease; chromosome 3p25 相似文献
Keywords: congenital heart disease; chromosome 3p25 相似文献
62.
Waters WF Hurry MJ Binks PG Carney CE Lajos LE Fuller KH Betz B Johnson J Anderson T Tucci JM 《Behavioral sleep medicine》2003,1(2):81-101
This investigation compared progressive muscle relaxation plus cognitive distraction (PMR/CD), hypothesized to better improve sleep onset, versus sleep restriction and stimulus control (SR/SC), hypothesized to better improve sleep maintenance, versus a flurazepam (Dalmane) positive contrast condition (MED) and a sleep hygiene education minimal treatment control condition (SHE). Participants with chronic insomnia (N = 53), completed 2 baseline weeks of sleep diaries, and were randomly assigned to a treatment group for 2 more weeks. In the second phase, PMR/CD participants were assigned to 2 weeks of PMR/CD + SR/SC + SHE while SHE participants continued SHE. Results indicated that PMR/CD had greater effect upon sleep onset than SR/SC and SHE, SR/SC had greater effect on sleep maintenance than PMR/CD, and MED was better than the other treatments. In the second phase, the treatment package produced modest additional improvements and SHE performed superior to expectations. 相似文献
63.
This investigation was designed to test (a) whether stimuli presented in the form of repeated blocks of habituation trials, as opposed to.1 single continuous series of stimuli, would produce a progressive decline. in amount of spontaneous recovery and trials to rehabituation of the skin conductance component of the orienting response; and (b) whether 30 or 50 post-habituation trials would produce a return of the orienting response which could be related In sensitization effects. Results showed that repeated habituations strengthened habituation as reflected in progressively decreasing spontaneous recovery across blocks, but not in speed of habituations. Further, neither 30 nor 50 post-habituation trials produced a return of the orienting response, although 30 such trials did result in increased skin conductance level. Discussion centers on whether habituation beyond asymptotic levels (‘below-zero’) within sessions was unambiguously obtained; relationships among stimulus intensity, frequency, and the return of the orienting response; and factors affecting measures of retention of habituation within sessions. 相似文献
64.
CD4 responses to conserved HIV-1 T helper epitopes show both negative and positive associations with virus load in chronically infected subjects 总被引:1,自引:0,他引:1
Boaz MJ Waters A Murad S Easterbrook PJ D'Sousa E van Wheeley C Vyakarnam A 《Clinical and experimental immunology》2003,134(3):454-463
Characterization of immune responses to immunodominant CD4 epitopes in HIV-1 that are associated with control of HIV infection could be used to strengthen the efficacy of polyepitope HIV vaccines. We measured both the proliferative and the CD4 interferon (IFN)-gamma and interleukin (IL)-2 cytokine responses specific for 11 previously identified HIV-1 T helper epitopes in 10 HIV-infected non-progressors (LTNPs) (infected for a median of 15 years with a stable CD4 count of >500 cells x 10(6)/l), and seven slow progressors (SPs) (infected for a median of 15 years with a CD4 count that had declined to <500 cells x 10(6)/l). Both groups were antiretroviral treatment-naive at the time of evaluation. The median virus load of SP group was higher than that of the LTNP group (P = 0.0002). The CD4 response to a peptide pool representing all potential CD4 Gag epitopes and to Gag p24 protein was also studied. Compared to SPs, LTNPs had higher numbers of Gag-specific IFN-gamma+IL-2+ CD4s (P = 0.0059). The Gag-specific cytokine and proliferative responses correlated inversely with virus load (P = 0.03 and 0.0002, respectively), highlighting the potential importance of this response in immunity to HIV. A direct correlation was noted between proliferation and the Gag-specific IL-2 (P = 0.0053) rather than IFN-gamma response (P = 0.1336), demonstrating that the proliferation assay reflected the IL-2 rather than the IFN-gamma secreting capacity of CD4 cells. Several subjects with diverse class II DRB1 alleles responded, confirming the 11 selected peptides to be both antigenic and conserved. CD4 cytokine responses to one Gag and two conserved Pol peptides correlated negatively with virus load. The cytokine response to two additional Pol peptides correlated positively with virus load. The data indicate that there is not an absolute correlation between the CD4 immune response to conserved and broadly antigenic helper T cell epitopes in HIV non-progression. 相似文献
65.
The data in this paper show that when the inhibition of growthis measured, xeroderma pigmentosum (XP) complementation groupsA, G and D are very sensitive to 4-nitroquinoline-1-oxide (4NQO),whereas only XP groups G and D are very sensitive to 3-methyl-4NQO(3me4NQO). Cells belonging to XP-C group are not particularlysensitive to either agent. Thus there are different epistasisgroups for the excision repair of DNA adducts induced by theseagents as opposed to the repair of u.v. damage. DNA polymerase is involved in the repair of 4NQO-induced lesions because aphidicolinblocks their repair. XP cells from all the above groups aredefective to some extent in this repair. The degree of repairdefectiveness follows that seen after u.v., with even the XP-Ccell line used having reduced repair (despite the fact thatthe inhibition of growth by 4NQO in this cell line was not markedlydifferent from normal). Aphidicolin did not induce breaks inthe normal or XP cell lines exposed to 3me4NQO, thus the repairof lesions induced by 3me4NQO does not involve DNA polymerase in any of the cell lines. Finally, catalase reduces the alkalinelabile lesions induced by 4NQO, but not 3me4NQO, suggestingthe latter agent does not induce substantial amounts of DNAdamage by the generation of radicals. 相似文献
66.
Fernandes Priyanka Wang Karina Timmerman Jason Reyes Angela Holmes Faye Olaleye Omonike A. Salihu Hamisu M. Moerchen Victoria A. Belcher Harolyn M. E. Copeland-Linder Nikeea Noble Charlotte A. Vamos Cheryl A. Armstrong Anna Waters Catrina R. Long-White Deneen Brown Claudia Reddy Madhavi M. Kuo Alice 《Maternal and child health journal》2022,26(7):1415-1423
Maternal and Child Health Journal - The Maternal and Child Health (MCH) Pipeline Training Program, promotes development of a diverse health workforce by training undergraduate students from... 相似文献
67.
68.
69.
Dong WW Brau CA Waters JW Tompkins PA Carroll FC Price RR Pickens DR Roos CF 《Journal of X-ray science and technology》1994,4(4):346-352
The Vanderbilt University medical FEL (free electron laser) Compton x-ray program is close to being operational. The FEL modifications necessary for this new capability are near completion. The transport and detection systems for electron and IR beams have been designed, delivered, and tested. We initially expect to produce 108 x-ray photons per second in the 15- to 20-keV region. 相似文献
70.
Sheila D. Banks Kathleen A. Waters Linda L. Barrett Scott Dickerson William Pendergast Gary K. Smith 《Cancer chemotherapy and pharmacology》1994,33(6):455-459
The activity of a novel thymidylate synthase inhibitor, 1843U89, against WiDr human colon carcinoma multicellular tumor spheroids was investigated. Continuous exposure of the spheroids to 3 nM 1843U89 for 10 days resulted in spheroid disruption, whereas 100 nM methotrexate (MTX) was required for similar effects. Short-term treatment experiments demonstrated that a 3-day exposure to 100 nM 1843U89 caused spheroid disruption 9 days after drug removal. A 4-day exposure to 10 nM 1843U89 caused spheroid disruption 8 days after drug removal. In contrast, treatment with 10 or 100 nM 1843U89 for 6–48 h or treatment with 1 nM 1843U89 for up to 5 days caused only growth delay. Continuous exposure of spheroids to 30 nM 1843U89 in the presence of 0.05–0.3 M thymidine was as effective in causing spheroid disruption as treatment in the absence of thymidine, but treatment in the presence of 0.7–3.0 M thymidine caused partial reversal of spheroid disruption. The results of these experiments suggest that 1843U89 should have potent solid tumor activity in humans but should be less effective in mice due to differences in circulating thymidine levels (0.1 vs 1 M, respectively). 相似文献