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Davis C, Bradshaw CM, Szabadi E. The Doors and People Memory Test: validation of norms and some new correction formulae. BRITISH JOURNAL OF CLINICAL PSYCHOLOGY 1999; 38:305-14. [PMID: 10532152 DOI: 10.1348/014466599162881] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
OBJECTIVES To validate the normative data on the Doors and People Memory Test (D&P) using a new sample of normal participants, and to investigate the relationship between D&P performance and general intellectual level. DESIGN 281 normal participants (16-75 years), subdivided into 10-year age bands, were tested on the D&P and the National Adult Reading Test (NART). METHOD Each participant's raw scores on the D&P were converted into scaled scores, and scaled memory 'indices' were derived using the test manual. Stepwise multi-linear regression was used to predict the indices using age and NART error score as predictor variables. For each participant the discrepancy between the predicted and obtained values of each index was converted into a [symbol: see text] score using the SD of the discrepancies from the whole sample. RESULTS The distributions of raw and scaled scores on the D&P were similar to those of the original standardization sample. The Visual-Verbal and Recall-Recognition Discrepancy indices had smaller dispersions in the present sample than in the original sample. None of the indices was significantly related to age. The Total Memory, Combined Visual Memory, Combined Verbal Memory, and Overall Forgetting indices were significantly correlated with NART error score. CONCLUSIONS The present data constitute a cross-validation of the normative data presented in the D&P test manual. Two points of dissimilarity are noted: (i) cutting scores derived for the Visual-Verbal and Recall-Recognition indices based on the test manual norms may be unduly conservative; and (ii) the relationship between some of the D&P indices and NART error score may lead to systematic errors in interpreting the scaled scores derived from the manual. 'Correction formulae' based on the regression equations derived from the present sample are provided.
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352
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Lang NP, Nowell S, Malfatti MA, Kulp KS, Knize MG, Davis C, Massengill J, Williams S, MacLeod S, Dingley KH, Felton JS, Turteltaub KW. In vivo human metabolism of [2-14C]2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Cancer Lett 1999; 143:135-8. [PMID: 10503892 DOI: 10.1016/s0304-3835(99)00142-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To better understand the interactions of the pathways of activation and detoxification on the metabolism of the putative carcinogen, PhIP, we administered a dose of 70-84 microg [2-14C] PhIP (17.5 [microCi 14C) 48-72 h before scheduled colon surgery. Blood and urine collected for the next 48-72 h was evaluated by linear accelerator mass spectroscopy (AMS) and scintillation counting LC-MS to identify specific PhIP metabolites. The thermostable phenol sulfotransferase (SULT1A1) phenotype was correlated with the 4'-PhIP-SO4 levels in the urine at 0-4 h (R = 0.86, P = 0.059). The CYP1A2 activity had a negative correlation with PhIP serum levels at 1 h (R = 0.94, P = 0.06) and a positive correlation with urine N-OH-PhIP levels at 0-4 h (R = 0.85, P = 0.15). This low level radioisotope method of determining the influence of phenotype on metabolism will significantly improve our understanding of the interrelationships of these pathways and provide a critical foundation for the development of individual risk assessment.
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353
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Hao W, Davis C, Hirsch IB, Eng LJ, Daniels T, Walsh D, Lernmark A. Plasmapheresis and immunosuppression in stiff-man syndrome with type 1 diabetes: a 2-year study. J Neurol 1999; 246:731-5. [PMID: 10460456 DOI: 10.1007/s004150050443] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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354
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Jones C, Phillips E, Davis C, Arbuckle J, Yaqoob M, Burgess GM, Docherty RJ, Webb M, Bevan SJ, McIntyre P. Molecular characterisation of cloned bradykinin B1 receptors from rat and human. Eur J Pharmacol 1999; 374:423-33. [PMID: 10422787 DOI: 10.1016/s0014-2999(99)00315-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This report describes the characterisation of cloned rat and human bradykinin B1 receptors in African green monkey kidney fibroblast (Cos-7) cells. A ligand binding assay with [3H]des-Arg10-kallidin was used to compare their pharmacology with respect to known bradykinin B1 and B2 receptor ligands. In addition, the pharmacology of T-kinin and its' derivative des-Arg11-T-kinin was investigated. The cloned rat receptor had a similar pharmacology to that of the recently described mouse receptor and differs from that described for the human receptor. The rat receptor had a higher affinity for des-Arg11-T-kinin than the human receptor. These differences in pharmacological properties may relate to the presence of T-kinin, bradykinin and their des-Arg derivatives as the major physiological peptides in rat and the predominance of kallidin and its derivatives in human. We confirm that the rat bradykinin B1 receptor gene is organised in a two exon structure and differs from the human gene which has a three exon structure and we further examine the inducible expression of this gene in a wide range of tissues using Northern blotting.
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MESH Headings
- Amino Acid Sequence
- Animals
- Binding, Competitive
- Blotting, Northern
- COS Cells
- Cell Line
- Cloning, Molecular
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- Female
- Gene Expression
- Genes/genetics
- Humans
- Kallidin/analogs & derivatives
- Kallidin/metabolism
- Molecular Sequence Data
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Rats
- Rats, Wistar
- Receptor, Bradykinin B1
- Receptors, Bradykinin/genetics
- Receptors, Bradykinin/metabolism
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Tissue Distribution
- Tritium
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355
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Cox JH, Garner RP, Redfield RR, Aronson NE, Davis C, Ruiz N, Birx DL. Antibody-dependent cellular cytotoxicity in HIV type 1-infected patients receiving VaxSyn, a recombinant gp160 envelope vaccine. AIDS Res Hum Retroviruses 1999; 15:847-54. [PMID: 10381173 DOI: 10.1089/088922299310755] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Antibody-dependent cellular cytotoxicity (ADCC) activity was measured in 60 human immunodeficiency virus (HIV-1)-infected patients receiving a recombinant gp160 (rgp160) envelope protein of HIV-1(NL4-3) in alum and 64 receiving placebo over a 5-year study period. There was no difference in the percentage of ADCC responders when comparing rgp160-immunized patients (mean, 78.4%) with those receiving placebo alone (mean, 81.5%) at any time point examined. Patients were further divided into progression groups regardless of their vaccine status. ADCC activity was somewhat higher in rapid than in slow-progressing groups, although the number that had detectable ADCC activity was equivalent in each group. ADCC activity of sera from rapid- and slow-progressing groups against primary or laboratory isolate envelopes was similar. This study showed that transcription with rgp160 did not appear to enhance HIV-specific ADCC activity. ADCC activity did not appear to correlate with protection against AIDS in this cohort of HIV-1-infected people.
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356
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Andrews S, Davis C. Interactive activation accounts of morphological decomposition: finding the trap in mousetrap? BRAIN AND LANGUAGE 1999; 68:355-361. [PMID: 10433781 DOI: 10.1006/brln.1999.2067] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Many accounts of the processing of morphologically complex words have been elaborated within the interactive activation model of word identification. Conceptually, this model adopts a "segmentation-through-recognition" approach to morphological decomposition, which assumes that a complex word activates representations of constituent morphemes as well as the representation of the whole word. However, a detailed consideration of the assumptions of interactive activation frameworks reveals that current implementations of the model are incapable of achieving segmentation-through-recognition.
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357
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Davis C, Katzman DK, Kirsh C. Compulsive physical activity in adolescents with anorexia nervosa: a psychobehavioral spiral of pathology. J Nerv Ment Dis 1999; 187:336-42. [PMID: 10379720 DOI: 10.1097/00005053-199906000-00002] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The excessive exercising that is frequently observed in anorexia nervosa (AN) has been viewed both as an addictive behavior and as a type of obsessive compulsive disorder. The present study tested a nonrecursive structural equation model that specified associations among personality factors, cognitions, and behavior in the development and progression of excessive exercise in adolescent patients with AN. As proposed, findings indicated that both addictive personality and obsessive-compulsive personality contributed to excessive exercising by means of their influence on obligatory/pathological cognitions about exercising. Childhood physical activity also predicted excessive exercising. The implications of these results are discussed from a psychobiological perspective.
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358
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Davis C. Big dogs make a difference. FUND RAISING MANAGEMENT 1999; 30:21-4. [PMID: 10538276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
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359
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Gough RE, Cox WJ, Davis C. Studies with an inactivated pheasant rotavirus vaccine. Vet Rec 1999; 144:423-4. [PMID: 10331233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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360
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Malfatti MA, Kulp KS, Knize MG, Davis C, Massengill JP, Williams S, Nowell S, MacLeod S, Dingley KH, Turteltaub KW, Lang NP, Felton JS. The identification of [2-(14)C]2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine metabolites in humans. Carcinogenesis 1999; 20:705-13. [PMID: 10223203 DOI: 10.1093/carcin/20.4.705] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
[2-(14)C]2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine ([14C]PhIP), a putative human carcinogenic heterocyclic amine found in well-done cooked meat, was administered orally to three colon cancer patients undergoing a partial colonectomy. Forty-eight to seventy-two hours prior to surgery, subjects received a 70-84 microg dose of 14C. Urine and blood were analyzed by HPLC for PhIP and PhIP metabolites. Metabolites were identified based on HPLC co-elution with authentic PhIP metabolite standards, mass spectral analysis and susceptibility to enzymatic cleavage. In two subjects, approximately 90% of the administered [14C]PhIP dose was eliminated in the urine, whereas in the other, only 50% of the dose was found in the urine. One subject excreted three times more radioactivity in the first 4 h than did the others. Twelve radioactive peaks associated with PhIP were detected in the urine samples. The relative amount of each metabolite varied by subject, and the amounts of each metabolite within subjects changed over time. In all three subjects the most abundant urinary metabolite was identified as 2-hydroxyamino-1-methyl-6-phenylimidazo[4,5-b]pyridine-N2-glucuron ide (N-hydroxy-PhIP-N2-glucuronide), accounting for 47-60% of the recovered counts in 24 h. PhIP accounted for <1% of the excreted radiolabel in all three patients. Other metabolites detected in the urine at significant amounts were 4-(2-amino-1-methylimidazo[4,5-b]pyrid-6-yl)phenyl sulfate, N-hydroxy-PhIP-N3-glucuronide and PhIP-N2-glucuronide. In the plasma, N-hydroxy-PhIP-N2-glucuronide accounted for 60, 18 and 20% of the recovered plasma radioactivity at 1 h post PhIP dose in subjects 1, 2 and 3 respectively. Plasma PhIP was 56-17% of the recovered dose at 1 h post exposure. The relatively high concentration of N-hydroxy-PhIP-N2-glucuronide and the fact that it is an indicator of bioactivation make this metabolite a potential biomarker for PhIP exposure and activation. Determining the relative differences in PhIP metabolites among individuals will indicate metabolic differences that may predict individual susceptibility to carcinogenic risk from this suspected dietary carcinogen.
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361
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Newton KM, Wagner EH, Ramsey SD, McCulloch D, Evans R, Sandhu N, Davis C. The use of automated data to identify complications and comorbidities of diabetes: a validation study. J Clin Epidemiol 1999; 52:199-207. [PMID: 10210237 DOI: 10.1016/s0895-4356(98)00161-9] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We evaluated the accuracy of administrative data for identifying complications and comorbidities of diabetes using International Classification of Diseases, 9th edition, Clinical Modification and Current Procedural Terminology codes. The records of 471 randomly selected diabetic patients were reviewed for complications from January 1, 1993 to December 31, 1995; chart data served to validate automated data. The complications with the highest sensitivity determined by a diagnosis in the medical records identified within +/-60 days of the database date were myocardial infarction (95.2%); amputation (94.4%); ischemic heart disease (90.3%); stroke (91.2%); osteomyelitis (79.2%); and retinal detachment, vitreous hemorrhage, and vitrectomy (73.5%). With the exception of amputation (82.9%), positive predictive value was low when based on a diagnosis identified within +/-60 days of the database date but increased with relaxation of the time constraints to include confirmation of the condition at any time during 1993-1995: ulcers (88.5%); amputation (85.4%); and retinal detachment, vitreous hemorrhage and vitrectomy (79.8%). Automated data are useful for ascertaining potential cases of some diabetic complications but require confirmatory evidence when they are to be used for research purposes.
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362
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Davis C. Heart link. Real-time cardiac telemedicine helps keep small Utah community hospital open. Allen Memorial Hospital. HEALTHCARE INFORMATICS : THE BUSINESS MAGAZINE FOR INFORMATION AND COMMUNICATION SYSTEMS 1999; 16:207-9. [PMID: 10346437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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363
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Ratto-Kim S, Sitz KV, Garner RP, Kim JH, Davis C, Aronson N, Ruiz N, Tencer K, Redfield RR, Birx DL. Repeated immunization with recombinant gp160 human immunodeficiency virus (HIV) envelope protein in early HIV-1 infection: evaluation of the T cell proliferative response. J Infect Dis 1999; 179:337-44. [PMID: 9878016 DOI: 10.1086/314587] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
This longitudinal study was designed to evaluate cellular immunity in early-stage, asymptomatic human immunodeficiency virus (HIV)-1-infected persons (CD4 cell count,>400/mm3; median, 625/mm3) who were immunized with either recombinant (r) gp160 or placebo every 2 months for 5 years. Proliferative responses were assessed against rgp160, rp24, and a panel of recall antigens and mitogens. Despite good reactivity to recall antigens, at baseline approximately 33% had proliferative responses to gp160, and approximately 42% showed p24 gag responses. There was no statistical difference between vaccine and placebo groups for antigens or mitogens. After 1 year, approximately 73% of the subjects in the vaccine arm had new or boosted responses to gp160, versus approximately 18% in the placebo arm. Statistical significance was maintained throughout the study. Recurrent vaccination with recombinant gp160 was proven to be persistently immunogenic, increasing significantly the ability of HIV-1-infected persons to mount new proliferative responses to the vaccine.
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364
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Sarig R, Mezger-Lallemand V, Gitelman I, Davis C, Fuchs O, Yaffe D, Nudel U. Targeted inactivation of Dp71, the major non-muscle product of the DMD gene: differential activity of the Dp71 promoter during development. Hum Mol Genet 1999; 8:1-10. [PMID: 9887326 DOI: 10.1093/hmg/8.1.1] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The dystrophin gene, which is defective in Duchenne muscular dystrophy (DMD), also encodes a number of smaller products controlled by internal promoters. Dp71, which consists of the two C-terminal domains of dystrophin, is the most abundant product of the gene in non-muscle tissues and is the major product in adult brain. To study the possible function of Dp71 and its expression during development, we specifically inactivated the expression of Dp71 by replacing its first and unique exon and a part of the concomitant intron with a beta-galactosidase reporter gene. X-Gal staining of Dp71-null mouse embryos and tissues revealed a very stage- and cell type-specific activity of the Dp71 promoter during development and during differentiation of various tissues, including the nervous system, eyes, limb buds, lungs, blood vessels, vibrissae and hair follicles. High activity of the Dp71 promoter often seemed to be associated with morphogenic events and terminal differentiation. In some tissues the activity greatly increased towards birth.
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365
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Davis C, Katzman MA. Perfection as acculturation: psychological correlates of eating problems in Chinese male and female students living in the United States. Int J Eat Disord 1999; 25:65-70. [PMID: 9924654 DOI: 10.1002/(sici)1098-108x(199901)25:1<65::aid-eat8>3.0.co;2-w] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE The purpose of this study was to assess the relationship between acculturation, self-esteem, depression, and characteristics associated with eating disorders among Chinese university students in the United States. METHOD A self-report questionnaire which included an acculturation scale (SL-ASIA), Center for Epidemiologic Studies of Depression (CES-D), Index of Self Esteem (ISE), and the Eating Disorders Inventory (EDI) was administered to 197 Chinese university students in the United States (93 females and 104 males). RESULTS Highly acculturated females reported significantly higher EDI total scores, more maturity fears, and a greater sense of ineffectiveness. Males who were less acculturated also reported high ineffectiveness while high male scores on acculturation were associated with greater perfectionism. Overall, females reported more body dissatisfaction and drive for thinness, and respondents with high acculturation reported more perfectionism and interoceptive awareness. DISCUSSION The impact of perfecting onself or one's body as a means of acculturating is discussed along with potential gender differences in perceived efficacy in a new culture.
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366
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Alexander JS, Dayton T, Davis C, Hill S, Jackson TH, Blaschuk O, Symonds M, Okayama N, Kevil CG, Laroux FS, Berney SM, Kimpel D. Activated T-lymphocytes express occludin, a component of tight junctions. Inflammation 1998; 22:573-82. [PMID: 9824772 DOI: 10.1023/a:1022310429868] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
T-lymphocytes routinely traffic from the lymphoid and vascular compartments to the tissues during immune surveillance and inflammatory responses. This egress occurs without compromising endothelial barrier, which is maintained by tight junctions (zonula occludens). We report that T-lymphocytes up-regulate the expression of occludin, a major component of the tight junction in response to stimulation with phorbol ester (PMA) + calcium ionophore, CD3 antibody or T-cell receptor (TCR) antibody. Only activated T-lymphocytes express occludin; this adhesion molecule is nearly absent in resting T-lymphocytes. By immunofluorescence, occludin is seen in lymphocyte aggregates, but does not appear to mediate aggregation since only 50% of the cells in these clusters express occludin. Occludin is expressed between 8 and 24 h following stimulation, and persists for at least 48 h. These data indicate that activated T cells produce occludin which may regulate lymphocyte adhesion and trafficking.
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367
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Nesnow S, Davis C, Padgett W, George M, Lambert G, Meyers F, Allison J, Adams L, King LC. Metabolic activation of racemic and enantiomeric trans-8, 9-dihydroxy-8,9-dihydrodibenzo[a,l]pyrene (dibenzo[def,p]chrysene) to dibenzo[a,l]pyrene-bis-dihydrodiols by induced rat liver microsomes and a recombinant human P450 1A1 system: the role of the K-region-derived metabolic intermediates in the formation of dibenzo[a,l]pyrene-DNA adducts. Chem Res Toxicol 1998; 11:1596-607. [PMID: 9860506 DOI: 10.1021/tx9801561] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Metabolic activation studies of dibenzo[a,l]pyrene (DB[a,l]P) (dibenzo[def,p]chrysene), an extremely potent environmental carcinogen, have been focused on metabolism at the fjord region, a region associated with high mutagenic and carcinogenic activities of the corresponding fjord-region DB[a,l]P-11,12-diol-13,14-epoxides. DB[a,l]P is metabolized by beta-naphthoflavone (BNF)- and 3-methylcholanthrene-induced rat liver microsomes and a recombinant human P450 1A1 system to two major dihydrodiols, the K-region dihydrodiol, DB[a,l]P-8,9-dihydrodiol (DB[a,l]P-8,9-diol), and the fjord-region dihydrodiol, DB[a,l]P-11,12-dihydrodiol. We have investigated the further metabolic activation of DB[a,l]P-8,9-diol by BNF-induced rat liver microsomes and a recombinant human P450 1A1 system with epoxide hydrolase to DB[a,l]P-bis-diols and to DNA adducts. (+/-)-trans-DB[a,l]P-8,9-diol was synthesized and resolved into its enantiomers. Racemic trans-DB[a,l]P-8,9-diol was metabolized by BNF-induced rat liver microsomes to six metabolites: two diastereomers of trans,trans-DB[a,l]P-8,9:11,12-bis-diol, two diastereomers of trans,cis-DB[a,l]P-8,9:11,12-bis-diol, and two diastereomers of trans-DB[a,l]P-8,9:13,14-bis-diol as characterized by NMR, MS, and UV spectroscopy. Metabolic studies using both enantiomeric (-)- and (+)-trans-DB[a,l]P-8,9-diol further demonstrated that each diastereomer of trans,trans-DB[a,l]P-8,9:11, 12-bis-diol and trans-DB[a,l]P-8,9:13,14-bis-diol was comprised of two enantiomers. Similarly, incubations of enantiomeric or racemic trans-DB[a,l]P-8,9-diol with a recombinant human P450 1A1 system and epoxide hydrolase also gave the same two enantiomeric mixtures of diastereomers of trans,trans-DB[a,l]P-8,9:11,12-bis-diol and the same two enantiomeric mixtures of diastereomers of trans-DB[a,l]P-8, 9:13,14-bis-diol. This suggested that the microsomal oxidations of (-)- and (+)-trans-DB[a,l]P-8,9-diol were stereospecific. The stereospecific formation of enantiomers of trans-DB[a,l]P-8,9-diol from DB[a,l]P was examined using both BNF-induced rat liver microsomes and a recombinant human P450 1A1 system with epoxide hydrolase. Stereospecificity was observed as both metabolic systems favored the formation of (-)-trans-DB[a,l]P-8,9-diol by 8-9-fold. DNA adduct studies were undertaken using TLC/HPLC 32P-postlabeling techniques. In the presence of a recombinant human P450 1A1 system with epoxide hydrolase, DB[a,l]P gave two groups of calf thymus DNA adducts. The group of later-eluting adducts were identified as arising from syn- and anti-DB[a,l]P-11,12-diol-13,14-epoxides, while the more polar early-eluting adducts were derived, in part, from the further activation of trans-DB[a,l]P-8,9-diol. Our data indicate that, in P450 1A1-mediated microsomal incubations, DB[a,l]P is metabolized to trans-DB[a,l]P-8,9-diol which is further metabolized to DB[a,l]P-bis-diols. trans-DB[a,l]P-8,9-diol is metabolically activated to intermediates that can bind to DNA and give DNA adducts similar to those observed with DB[a,l]P. These results indicate that DB[a,l]P can be metabolically activated by both fjord-region and K-region pathways.
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368
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Mann DL, Garner RP, Dayhoff DE, Cao K, Fernández-Viña MA, Davis C, Aronson N, Ruiz N, Birx DL, Michael NL. Major histocompatibility complex genotype is associated with disease progression and virus load levels in a cohort of human immunodeficiency virus type 1-infected Caucasians and African Americans. J Infect Dis 1998; 178:1799-802. [PMID: 9815238 DOI: 10.1086/314519] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
To assess the influence of HLA on AIDS-free survival, human immunodeficiency virus load, and CD4 cell counts, 91 Caucasian and 48 African-American seroprevalent men were typed for HLA classes I and II and TAP alleles. HLA associations with these markers were assessed by assigning sum integer scores based on 7 class I allele-TAP variants (+1) and 13 class I-class II-TAP combinations (-1) with different AIDS-free survival times found in a prior study. Subjects in both racial groups and combined with positive sum scores were less likely to have CD4 cell decline (P=.0004), to have increased virus burden (P=.014), and to develop AIDS (P=.034) in the follow-up period than were Caucasians and African Americans with scores of 0 or -1. These results confirm the reported associations of specific major histocompatibility complex genes with AIDS-free survival time in Caucasians and specifically extend them to African Americans and to two established markers of disease progression.
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369
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Jiang Y, Davis C, Broach JR. Efficient transition to growth on fermentable carbon sources in Saccharomyces cerevisiae requires signaling through the Ras pathway. EMBO J 1998; 17:6942-51. [PMID: 9843500 PMCID: PMC1171042 DOI: 10.1093/emboj/17.23.6942] [Citation(s) in RCA: 86] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Strains carrying ras2(318S) as their sole RAS gene fail to elicit a transient increase in cAMP levels following addition of glucose to starved cells but maintain normal steady-state levels of cAMP under a variety of growth conditions. Such strains show extended delays in resuming growth following transition from a quiescent state to glucose-containing growth media, either in emerging from stationary phase or following inoculation as spores onto fresh media. Otherwise, growth of such strains is indistinguishable from that of RAS2(+) strains. ras2(318S) strains also exhibit a delay in glucose-stimulated phosphorylation and turnover of fructose-1,6-bisphosphatase, a substrate of the cAMP-dependent protein kinase A (PKA) and a key component of the gluconeogenic branch of the glycolytic pathway. Finally Tpk(w) strains, which fail to modulate PKA in response to fluctuations in cAMP levels, show the same growth delay phenotypes, as do ras2(318S) strains. These observations indicate that the glucose-induced cAMP spike results in a transient activation of PKA, which is required for efficient transition of yeast cells from a quiescent state to resumption of rapid growth. This represents the first demonstration that yeast cells use the Ras pathway to transmit a signal to effect a biological change in response to an upstream stimulus.
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370
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Davis C, Noel MB, Chan SF, Wing LS. Knowledge, attitudes and behaviours related to HIV and AIDS among chinese adolescents in hong kong. J Adolesc 1998; 21:657-65. [PMID: 9971723 DOI: 10.1006/jado.1998.0186] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The purpose of this study was to assess HIV and AIDS knowledge and attitudes, source of HIV and AIDS information, and behaviours related to HIV and AIDS among Chinese adolescents in Hong Kong. Participants included 1259 (826 females and 433 males) Chinese adolescents in Hong Kong between 12-18 years of age. Findings revealed that over 80% of the adolescents had rarely or never discussed HIV and AIDS with their family or teacher, and the primary source of HIV and AIDS information was media sources such as television and newspapers. Findings revealed HIV and AIDS misinformation among both male and female adolescents in the areas of transmission, facts, personal vulnerability and attitudes. However, participants reported engaging in little at-risk behaviour associated with HIV and AIDS. Implications for HIV and AIDS education and prevention are discussed.
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Nagashunmugam T, Malamud D, Davis C, Abrams WR, Friedman HM. Human submandibular saliva inhibits human immunodeficiency virus type 1 infection by displacing envelope glycoprotein gp120 from the virus. J Infect Dis 1998; 178:1635-41. [PMID: 9815215 DOI: 10.1086/314511] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Human submandibular saliva reduces human immunodeficiency virus type 1 (HIV-1) infection in vitro. To define the mechanism of inhibition, virus was incubated with saliva or medium, velocity sucrose gradient centrifugation was performed, and fractions were analyzed for p24 and gp120. The results show that after incubation with saliva, the envelope glycoprotein was displaced from both a laboratory-adapted and a low-passage clinical HIV-1 isolate. To identify the salivary protein(s) responsible, submandibular saliva was fractionated by anion- exchange chromatography. Protein fractions containing anti-HIV activity were assayed for their ability to strip gp120 from virus. The partially purified active fractions contained two high-molecular-weight sialyated glycoproteins identified as salivary agglutinin and mucin, as well as several lower-molecular-weight proteins. It thus appears that specific salivary proteins interact with HIV-1 to strip gp120 from the virus with a resultant decrease in infectivity.
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372
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Leveille SG, Wagner EH, Davis C, Grothaus L, Wallace J, LoGerfo M, Kent D. Preventing disability and managing chronic illness in frail older adults: a randomized trial of a community-based partnership with primary care. J Am Geriatr Soc 1998; 46:1191-8. [PMID: 9777899 DOI: 10.1111/j.1532-5415.1998.tb04533.x] [Citation(s) in RCA: 190] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Effective new strategies that complement primary care are needed to reduce disability risks and improve self-management of chronic illness in frail older people living in the community. OBJECTIVE To evaluate the impact of a 1-year, senior center-based chronic illness self-management and disability prevention program on health, functioning, and healthcare utilization in frail older adults. DESIGN A randomized controlled trial. SETTING A large senior center located in a northeast Seattle suburb. The trial was conducted in collaboration with primary care providers of two large managed care organizations. PARTICIPANTS A total of 201 chronically ill older adults seniors aged 70 and older recruited through medical practices. INTERVENTION A targeted, multi-component disability prevention and disease self-management program led by a geriatric nurse practitioner (GNP). MEASUREMENTS Self-reported Physical function, physical performance tests, health care utilization, and health behaviors. RESULTS Each of 101 intervention participants met with the GNP from 1 to 8 times (median = 3) during the study year. The intervention group showed less decline in function, as measured by disability days and lower scores on the Health Assessment Questionnaire. Other measures of function, including the SF-36 and a battery of physical performance tests, did not change with the intervention. The number of hospitalized participants increased by 69% among the controls and decreased by 38% in the intervention group (P = .083). The total number of inpatient hospital days during the study year was significantly less in the intervention group compared with controls (total days = 33 vs 116, P = .049). The intervention led to significantly higher levels of physical activity and senior center participation and significant reductions in the use of psychoactive medications. CONCLUSIONS This project provides evidence that a community-based collaboration with primary care providers can improve function and reduce inpatient utilization in chronically ill older adults. Linking organized medical care with complementary community-based interventions may be a promising direction for research and practice.
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373
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Davis C, Leveille S, Favaro S, LoGerfo M. Benefits to volunteers in a community-based health promotion and chronic illness self-management program for the elderly. J Gerontol Nurs 1998; 24:16-23. [PMID: 9923237 DOI: 10.3928/0098-9134-19981001-06] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. Volunteers for health promotion programs tend to be younger and healthier than program participants. 2. Volunteers in a health promotion program reported improved health and function. 3. Nurses involved in health promotion programs can extend their efforts by using trained volunteers.
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374
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Conway P, Davis C, Hartel T, Russell G. Simultaneous kidney pancreas transplantation: patient issues and nursing interventions. ANNA JOURNAL 1998; 25:455-60, 478; quiz 461-2. [PMID: 9887698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Nursing care across the service delivery continuum is essential for patients undergoing simultaneous kidney pancreas transplantation. The self-management of complicated treatment choices and care regimens requires education and support, which are the domain of transplant nursing coordinators. Even successful transplantation is associated with complications in the first 6 months. Continuous posttransplant nursing interventions to monitor patients, teach and reinforce self-care, and support adjustment is crucial to patient well-being. This article describes nursing strategies used at one transplant center to address these patient needs.
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375
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Dosil M, Giot L, Davis C, Konopka JB. Dominant-negative mutations in the G-protein-coupled alpha-factor receptor map to the extracellular ends of the transmembrane segments. Mol Cell Biol 1998; 18:5981-91. [PMID: 9742115 PMCID: PMC109184 DOI: 10.1128/mcb.18.10.5981] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/1998] [Accepted: 06/30/1998] [Indexed: 11/20/2022] Open
Abstract
G-protein-coupled receptors (GPCRs) transduce the signals for a wide range of hormonal and sensory stimuli by activating a heterotrimeric guanine nucleotide-binding protein (G protein). The analysis of loss-of-function and constitutively active receptor mutants has helped to reveal the functional properties of GPCRs and their role in human diseases. Here we describe the identification of a new class of mutants, dominant-negative mutants, for the yeast G-protein-coupled alpha-factor receptor (Ste2p). Sixteen dominant-negative receptor mutants were isolated based on their ability to inhibit the response to mating pheromone in cells that also express wild-type receptors. Detailed analysis of two of the strongest mutant receptors showed that, unlike other GPCR interfering mutants, they were properly localized at the plasma membrane and did not alter the stability or localization of wild-type receptors. Furthermore, their dominant-negative effect was inversely proportional to the relative amount of wild-type receptors and was reversed by overexpressing the G-protein subunits, suggesting that these mutants compete with the wild-type receptors for the G protein. Interestingly, the dominant-negative mutations are all located at the extracellular ends of the transmembrane segments, defining a novel region of the receptor that is important for receptor signaling. Altogether, our results identify residues of the alpha-factor receptor specifically involved in ligand binding and receptor activation and define a new mechanism by which GPCRs can be inactivated that has important implications for the evaluation of receptor mutations in other G-protein-coupled receptors.
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