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Grodstein F, Chen J, Pollen DA, Albert MS, Wilson RS, Folstein MF, Evans DA, Stampfer MJ. Postmenopausal hormone therapy and cognitive function in healthy older women. J Am Geriatr Soc 2000; 48:746-52. [PMID: 10894312 DOI: 10.1111/j.1532-5415.2000.tb04748.x] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Accumulating biologic evidence suggests that estrogen is related to cognitive function. Several epidemiologic investigations have reported that hormone therapy may reduce the risk of Alzheimer's disease. However, fewer studies have examined the relation of postmenopausal hormone use to general cognitive function in nondemented older women. Thus, we examined the association of hormone therapy to performance on four cognitive tests among healthy participants of the Nurses' Health Study. DESIGN Cohort study. SETTING The Nurses' Health Study, an ongoing prospective cohort study begun in 1976. PARTICIPANTS From the Nurses' Health Study, 2138 women aged 70-78 years. MEASUREMENTS From 1995-1999 we administered four cognitive tests (Telephone Interview for Cognitive Status (TICS), immediate and delayed recall of the East Boston Memory Test (EBMT), and verbal fluency) by telephone. Hormone use was ascertained from biennial questionnaires beginning in 1976. Linear and logistic regression models were used to calculate multivariate-adjusted differences in scores and relative risks of a low score for never users compared to current and past hormone users. RESULTS After adjustment for confounders, neither current nor long-term hormone users demonstrated better performance on an overall measure of cognition (TICS), or on three tests of verbal memory (immediate and delayed recall of the EBMT, immediate recall of the TICS 10-word list) than never users. On the test of verbal fluency, current hormone users scored significantly better than never users (linear regression estimate of the difference in score = 0.78 points, 95% confidence interval (CI) 0.19-0.38, P = .01 for any current use; and 0.91 points, 95% CI 0.28-1.54, P = .005 for > or = 5 years current use). Current hormone users also had a 30% decrease (RR = 0.70, 95% CI 0.45-1.09) in their risk of a low score on the test of verbal fluency. These results were similar for women taking estrogen alone and estrogen combined with a progestin. CONCLUSIONS Verbal fluency may be enhanced among women taking postmenopausal hormones, however, there is little support for better overall cognitive function in hormone users than nonusers.
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Evans DA, De Bree FM, Nijenhuis M, Van Der Kleij AA, Zalm R, Korteweg N, Van Leeuwen FW, Burbach JP. Processing of frameshifted vasopressin precursors. J Neuroendocrinol 2000; 12:685-93. [PMID: 10849214 DOI: 10.1046/j.1365-2826.2000.00507.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Biosynthesis of the vasopressin (VP) prohormone in magnocellular neurones of the hypothalamo-neurohypophysial system comprises endoplasmic reticulum (ER) transit, sorting into the regulated secretory pathway and subsequent processing in the individual proteins VP, neurophysin and a glycoprotein. These processes are severely disrupted in the homozygous diabetes insipidus (di/di) Brattleboro rat, which expresses a mutant VP precursor due to a single nucleotide deletion in the neurophysin region of the VP gene resulting in VP deficiency. Previous studies have shown the presence of additional frameshift mutations in VP transcripts, in solitary magnocellular neurones of the di/di rat due to a GA dinucleotide deletion resulting in two different mutant VP precursors with partly restored reading frame. Frameshifted VP precursors are also expressed in several magnocellular neurones in wild-type rats. In this study, we determined if the +1 frameshifted precursors from di/di and wild-type rats can lead to biosynthesis of the hormone VP. Therefore, eukaryotic expression plasmids containing the frameshifted VP cDNAs were transiently expressed in peptidergic tumour cell lines, and cells were analysed by reversed phase high-performance liquid chromatography and specific radioimmunoassays, and by immunofluoresence. Neuro2A neuroblastoma cells expressing the +1 frameshifted precursors of di/di rats retained products in the cell body. Only precursor or insignificant quantities of neurophysin-immunoreactive products were detected. In contrast, in AtT20 cells, frameshifted VP precursors were at least partly processed to yield the VP peptide, indicating that they have access to the regulated secretory pathway. Comparison between the two cell lines showed a very slow ER transit of the wild-type prohormone combined with inefficient processing in Neuro2A cells. The results show that mutant precursors can reach the regulated secretory pathway if ER transport is sufficiently rapid as in the case of AtT20 cells. This suggests that the di/di rat may regain the capacity to biosynthesize authentic VP through these +1 frameshifted precursors in magnocellular neurones.
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Cronin-Stubbs D, DeKosky ST, Morris JC, Evans DA. Promoting interactions with basic scientists and clinicians: the NIA Alzheimer's Disease Data Coordinating Center. Stat Med 2000; 19:1453-61. [PMID: 10844710 DOI: 10.1002/(sici)1097-0258(20000615/30)19:11/12<1453::aid-sim437>3.0.co;2-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
To benefit Alzheimer's disease research, a central data co-ordinating centre (CDCC) is planned that will systematically collect data from 27 Alzheimer's disease centres (ADCs) located nationwide. This CDCC will combine, analyse and disseminate epidemiologic, demographic, clinical and neuropathological data to researchers from the ADCs and the broader scientific community. New and larger scale collaborative studies on Alzheimer's disease will be possible through this centre. Since 1 July 1997, an interim data co-ordinating centre (IDCC) has been serving as the agent of the ADCs to begin the data sharing process until a permanent CDCC is established. The data collected by the IDCC are limited to administrative information and to indexing of specimens and clinical material, with future plans for the transfer of the data collected to the CDCC once it is established.
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Wilson RS, Bennett DA, Gilley DW, Beckett LA, Schneider JA, Evans DA. Progression of parkinsonism and loss of cognitive function in Alzheimer disease. ARCHIVES OF NEUROLOGY 2000; 57:855-60. [PMID: 10867783 DOI: 10.1001/archneur.57.6.855] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To assess the relation between parkinsonism and cognitive function in Alzheimer disease from cross-sectional and longitudinal perspectives. DESIGN Prospective cohort study with annual clinical evaluations during a 4-year period. SETTING Alzheimer disease clinic in an urban medical center. PARTICIPANTS Four hundred ten persons with clinically diagnosed Alzheimer disease. MAIN OUTCOME MEASURES Global and specific measures of cognitive function and parkinsonism. RESULTS Higher levels of parkinsonism at baseline were reliably associated with lower levels of cognitive function at baseline and with more rapid cognitive decline during the 4-year study period. However, the associations were small, with baseline parkinsonism accounting for less than 10% of the variation either in baseline cognitive function or in the rate of cognitive decline. By contrast, rates of change in parkinsonism and cognitive function were strongly correlated, with 70% or more shared variance in the rates of change in many models. The association was observed with diverse measures of cognition and parkinsonism and was not explained by demographic variables or use of neuroleptic medications. CONCLUSION In Alzheimer disease, progressive worsening of parkinsonism is more strongly associated with cognitive decline than previously recognized. Arch Neurol. 2000.
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Latha PG, Evans DA, Panikkar KR, Jayavardhanan KK. Immunomodulatory and antitumour properties of Psoralea corylifolia seeds. Fitoterapia 2000; 71:223-31. [PMID: 10844159 DOI: 10.1016/s0367-326x(99)00151-3] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Psoralea corylifolia seed extract has been found to stimulate the immune system in mice. Administration of the extract was found to inhibit EAC ascitic tumour growth and stimulate natural killer cell activity, antibody-dependent cellular cytotoxicity, antibody-forming cells and the antibody complement-mediated cytotoxicity during tumour development.
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Johnson JS, Evans DA. Chiral bis(oxazoline) copper(II) complexes: versatile catalysts for enantioselective cycloaddition, Aldol, Michael, and carbonyl ene reactions. Acc Chem Res 2000; 33:325-35. [PMID: 10891050 DOI: 10.1021/ar960062n] [Citation(s) in RCA: 811] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
A bis(oxazoline) (box) copper(II) complex and its hydrated counterpart (1 and 2) function as enantioselective Lewis acid catalysts for carbocyclic and hetero Diels-Alder, aldol, Michael, ene, and amination reactions with substrates capable of chelation through six- and five-membered rings. X-ray crystallography of the chiral complexes reveals a propensity for the formation of distorted square planar or square pyramidal geometries. The sense of asymmetric induction is identical for all the processes catalyzed by [Cu((S,S)-t-Bu-box)](X)(2) complexes 1 and 2 (X = OTf and SbF) resulting from the intervention of a distorted square planar catalyst-substrate binary complex. These catalyzed processes exhibit excellent temperature-selectivity profiles. Reactions catalyzed by [Cu(S,S-Ph-pybox)](SbF(6))(2) and their derived chelation complexes are also discussed.
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Martin MW, Grazhdankin DV, Bowring SA, Evans DA, Fedonkin MA, Kirschvink JL. Age of Neoproterozoic bilatarian body and trace fossils, White Sea, Russia: implications for metazoan evolution. Science 2000; 288:841-5. [PMID: 10797002 DOI: 10.1126/science.288.5467.841] [Citation(s) in RCA: 303] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
A uranium-lead zircon age for a volcanic ash interstratified with fossil-bearing, shallow marine siliciclastic rocks in the Zimnie Gory section of the White Sea region indicates that a diverse assemblage of body and trace fossils occurred before 555.3 +/- 0.3 million years ago. This age is a minimum for the oldest well-documented triploblastic bilaterian Kimberella. It also makes co-occurring trace fossils the oldest that are reliably dated. This determination of age implies that there is no simple relation between Ediacaran diversity and the carbon isotopic composition of Neoproterozoic seawater.
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Aggarwal NT, Bennett DA, Bienias JL, Mendes de Leon CF, Morris MC, Evans DA. The prevalence of dizziness and its association with functional disability in a biracial community population. J Gerontol A Biol Sci Med Sci 2000; 55:M288-92. [PMID: 10819319 DOI: 10.1093/gerona/55.5.m288] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Information regarding the prevalence of dizziness and its association with functional disability among African American and white residents from defined community populations is limited. METHODS A total of 6,158 persons 65 years and older (78.8% of age-eligible persons) completed in-home interviews that included three common measures of self-reported disability: the Katz Activities of Daily Living (ADL) Scale, the Rosow-Breslau Functional Health Scale, and the Nagi Physical Disability Scale. A stratified random sample of 729 persons underwent a detailed evaluation that included questions on the frequency and severity of dizziness, which was defined as having an episode of dizziness or lightheadedness at least once a month. RESULTS The overall prevalence of dizziness in this population was 9.6% (95% confidence interval [CI] 7.2-12.0). It increased with age, from 6.6% in those 65-74 years old, to 11.6% in those 75-84 years old, and to 18.4% in those persons > or =85 years old. It was more common in women (odds ratio [OR] 2.03, 95% CI 0.99-4.19) but was not associated with race. After adjusting for age, sex, and race, dizziness was associated with greater disability on the Rosow-Breslau (OR 2.29, 95% CI 1.18-4.46) and Nagi (OR 2.54, 95% CI 1.48-4.36) measures but not on the Katz ADL Scale (OR 1.18, 95% CI 0.64-2.20). CONCLUSIONS Dizziness is common among older persons and is associated with functional disability.
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Wilson RS, Gilley DW, Bennett DA, Beckett LA, Evans DA. Person-specific paths of cognitive decline in Alzheimer's disease and their relation to age. Psychol Aging 2000. [PMID: 10755286 DOI: 10.1037//0882-7974.15.1.18] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Change in global and specific measures of cognitive function was studied in a cohort of 410 persons with Alzheimer's disease. Persons completed up to 5 annual evaluations; follow-up participation among survivors exceeded 90%. Average annual decline was 0.57 standard score units (95% confidence interval [CI]: -0.51 to -0.62) on a composite measure based on 17 individual tests and 3.26 points (95% CI: -3.06 to 3.46) on the Mini-Mental State Examination, but substantial heterogeneity was apparent. On both global and specific measures, rate of cognitive decline was reduced in older persons compared with younger persons. A similar effect was observed for estimated age of disease onset. The effect of age was approximately linear and was not attributable to education, sex, race, other conditions that impair cognition, or mortality. The results indicate that person-specific paths of cognitive decline in Alzheimer's disease vary substantially and suggest that in clinical settings some of this variability is related to age.
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Wilson RS, Bennett DA, Gilley DW, Beckett LA, Schneider JA, Evans DA. Progression of parkinsonian signs in Alzheimer's disease. Neurology 2000; 54:1284-9. [PMID: 10746599 DOI: 10.1212/wnl.54.6.1284] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To describe the progression of parkinsonian signs in persons with AD. BACKGROUND Parkinsonian signs are common in AD and appear to be related to morbidity and mortality. However, little is known about individual patterns of progression of parkinsonian signs. METHODS A cohort of 410 people with clinically diagnosed AD underwent annual clinical evaluations over a 4-year period, with over 90% of survivors participating in follow-up. The entire motor portion of the Unified Parkinson's Disease Rating Scale (UPDRS) was administered at each evaluation. Previously established measures of four parkinsonian signs were derived from the UPDRS. Scores ranged from 0 to 100 and represented the percent obtained of the total possible item score. RESULTS A growth curve approach was used to estimate individual paths of change. Rates of change in bradykinesia (4.5% increase per year), rigidity (6.0% increase per year), and gait disorder/postural reflex impairment (8.9% increase per year) were substantial and positively correlated (median r = 0.69). Change in tremor was minimal, mostly confined to postural tremor, and weakly correlated with change in other signs (median r = 0.16). The rate of progression in each sign was highly variable across individuals and not strongly related to demographic factors or use of neuroleptic medications. CONCLUSIONS Parkinsonian signs other than tremor progress rapidly in AD but at widely differing rates.
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Wilson RS, Gilley DW, Bennett DA, Beckett LA, Evans DA. Person-specific paths of cognitive decline in Alzheimer's disease and their relation to age. Psychol Aging 2000; 15:18-28. [PMID: 10755286 DOI: 10.1037/0882-7974.15.1.18] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Change in global and specific measures of cognitive function was studied in a cohort of 410 persons with Alzheimer's disease. Persons completed up to 5 annual evaluations; follow-up participation among survivors exceeded 90%. Average annual decline was 0.57 standard score units (95% confidence interval [CI]: -0.51 to -0.62) on a composite measure based on 17 individual tests and 3.26 points (95% CI: -3.06 to 3.46) on the Mini-Mental State Examination, but substantial heterogeneity was apparent. On both global and specific measures, rate of cognitive decline was reduced in older persons compared with younger persons. A similar effect was observed for estimated age of disease onset. The effect of age was approximately linear and was not attributable to education, sex, race, other conditions that impair cognition, or mortality. The results indicate that person-specific paths of cognitive decline in Alzheimer's disease vary substantially and suggest that in clinical settings some of this variability is related to age.
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Morris MC, Scherr PA, Hebert LE, Bennett DA, Wilson RS, Glynn RJ, Evans DA. The cross-sectional association between blood pressure and Alzheimer's disease in a biracial community population of older persons. J Gerontol A Biol Sci Med Sci 2000; 55:M130-6. [PMID: 10795724 DOI: 10.1093/gerona/55.3.m130] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The relation of blood pressure to Alzheimer's disease (AD) is complex because both an association of high blood pressure with increased risk of the disease and lower blood pressure as a consequence of the disease are possible. METHODS We examined the cross-sectional association of blood pressure and AD in the Chicago Health and Aging Project (CHAP), a study of a geographically defined, biracial community. After in-home interviews with 6.162 residents > or =65 years, a stratified random sample of 729 participants was clinically evaluated; 709 had blood pressures measured, and 243 were diagnosed with AD. RESULTS In logistic regression models adjusted for age, sex, education, and race there was no association between blood pressure measured as a continuous variable and Alzheimer's disease. In categorical analyses, however, prevalence of Alzheimer's disease was significantly higher among persons with low systolic pressure (<130 mmHg) compared with the referent group of 130-139 mmHg (odds ratio [OR] = 2.2, 95% confidence interval [CI]: 1.2,4.1), and with low diastolic pressure (<70 mmHg) compared to the referent of 70-79 mmHg (OR = 1.8, 95% CI: I. 1,3.1). High systolic and diastolic categories were not statistically different from the referent group, although there was some evidence that the associations differed by race. The odds ratios changed little with further adjustment for apolipoprotein E genotype, antihypertensive medications, body mass, stroke, diabetes, and heart disease. CONCLUSION These findings are consistent with previous studies showing associations between low blood pressure and AD, but longitudinal studies are needed to characterize cause-and-effect associations.
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Subramoniam A, Evans DA, Valsaraj R, Rajasekharan S, Pushpangadan P. Inhibition of antigen-induced degranulation of sensitized mast cells by Trichopus zeylanicus in mice and rats. JOURNAL OF ETHNOPHARMACOLOGY 1999; 68:137-43. [PMID: 10624873 DOI: 10.1016/s0378-8741(99)00077-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Treatment of mice with Trichopus zeylanicus leaf resulted in inhibition of antigen-induced degranulation of sensitized peritoneal mast cells. Further, it reduced the ratio of mast cells in the peritoneal exudate cells. The plant drug treatment did not protect mice from E. coli-induced abdominal sepsis. Studies in rats using mesenteric mast cells confirmed the above mast cell-stabilizing property of T. zeylanicus. This activity was found in the butanol fraction of methanol extract of T. zeylanicus leaf. The treatment with this fraction also reduced the number of rat mesenteric mast cells. However, the in vitro treatment of the mast cells with the butanol fraction did not inhibit antigen-induced degranulation of the mast cells.
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Wilson RS, Beckett LA, Bennett DA, Albert MS, Evans DA. Change in cognitive function in older persons from a community population: relation to age and Alzheimer disease. ARCHIVES OF NEUROLOGY 1999; 56:1274-9. [PMID: 10520945 DOI: 10.1001/archneur.56.10.1274] [Citation(s) in RCA: 95] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To examine change in cognitive function in older persons sampled from a community population, and its relation to age and Alzheimer disease. DESIGN Prospective cohort study with an average of 3.5 years of follow-up. SETTING East Boston, Mass--a geographically defined, urban, working-class community. PARTICIPANTS A stratified, random sample of persons 65 years and older underwent uniform, structured clinical evaluation for Alzheimer disease. The 388 persons (89.2% of those eligible) who completed at least 1 annual follow-up evaluation were studied: 97 had Alzheimer disease at baseline; 95 developed Alzheimer disease during the study; and 196 were unaffected. OUTCOME MEASURES Eight cognitive performance tests were administered, then converted to population-weighted z scores and averaged to create a composite summary measure of cognitive function. Initial level of and change in this score were the outcome measures. RESULTS In the population as a whole, many persons experienced a decline in cognitive performance, and age was related to both initial level and rate of decline. Analyses were conducted in 3 subgroups: persons with Alzheimer disease at baseline, those who developed Alzheimer disease during the study, and those who remained unaffected. In both Alzheimer disease subgroups, substantial cognitive decline was observed, but neither initial level nor rate of decline was related to age. In unaffected persons, little cognitive decline was evident, and there was a small, inverse association of age with initial level of cognitive function. CONCLUSION In a general population sample, there was little evidence of cognitive decline during a 3.5-year period among persons who remained free of Alzheimer disease.
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Evans DA, Willis MC, Johnston JN. Catalytic enantioselective Michael additions to unsaturated ester derivatives using chiral copper(II) Lewis acid complexes. Org Lett 1999; 1:865-8. [PMID: 10823215 DOI: 10.1021/ol9901570] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[formula: see text] Chiral Cu(II) bisoxazoline (box) Lewis acids have been developed as catalysts of the Michael addition of enolsilanes to unsaturated ester derivatives. While enantioselection is stereoregular, the sense of diastereoselection is directly related to thioester enolsilane geometry: (E) enolsilanes give anti adducts and (Z) enolsilanes afford syn adducts. The size of the enolsilane alkylthio substituent directly impacts the magnitude of diastereoselection.
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Passalacqua JA, Wiland AM, Fink JC, Bartlett ST, Evans DA, Keay S. Increased incidence of postoperative infections associated with peritoneal dialysis in renal transplant recipients. Transplantation 1999; 68:535-40. [PMID: 10480413 DOI: 10.1097/00007890-199908270-00016] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Infection is a frequent postoperative complication in renal transplant recipients. However, little information is available concerning the effect of pretransplantation dialysis modality on posttransplantation complications including infection. We therefore evaluated the effect of hemodialysis (HD) versus peritoneal dialysis (PD) on the incidence of postoperative infection as well as several other posttransplantation outcomes. METHODS A retrospective analysis was performed using medical records covering the period 30 days after transplantation of 156 dialysis patients who underwent renal transplantation at a single center during a 22-month period. Of these patients, 103 received only HD, 32 received only PD, 13 received PD in the past and HD immediately before transplantation (PH/HD), and 8 received HD in the past and PD immediately before transplantation (HD/PD). The presence of culture-proven infection, types of infecting organisms, length of initial hospital stay, and incidence of rejection during the first 30 days after transplantation were determined for each patient. RESULTS All groups were similar with regard to age, race, gender, underlying disease, donor type, incidence of delayed graft function, and perioperative antibiotic prophylaxis. There were more infectious complications within 30 days after transplantation in patients on PD just prior to transplantation (PD and HD/PD) than in HD patients (67.5% vs. 25.9%, P<0.00001). When types of infectious organisms were assessed, PD patients were found to have a greater incidence of infections with microorganisms that colonize human skin (P<0.0001). The median length of hospital stay was 3 days longer for PD patients and 6.5 days longer for HD/PD patients than for patients receiving HD (P=0.01 and 0.04), and PD and HD/PD patients were more likely to have an episode of rejection than HD patients (P=0.02). CONCLUSIONS Renal replacement therapy with PD immediately before transplantation negatively affects outcome as compared with HD, predisposing patients to a greater incidence of postoperative infections and rejection and a longer hospital stay. Further study in a randomized controlled trial may help determine how adjustment of the dialysis method can optimize transplantation outcome.
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Evans DA, Johnson DS. Catalytic enantioselective amination of enolsilanes using C2-symmetric copper(II) complexes as chiral Lewis acids. Org Lett 1999; 1:595-8. [PMID: 10823188 DOI: 10.1021/ol990113r] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[formula: see text] [Cu(S,S)-t-Bu-box](OTf)2 (1) catalyzes the enantioselective amination of enolsilanes with azodicarboxylate derivatives. Isomerically pure enolsilanes of aryl ketones, acylpyrroles, and thioesters added to the azo-imide in greater than 95% ee. The use of an alcohol additive was critical to achieving catalyst turnover.
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Evans DA, Cee VJ, Smith TE, Santiago KJ. Selective lithiation of 2-methyloxazoles. Applications to pivotal bond constructions in the phorboxazole nucleus. Org Lett 1999; 1:87-90. [PMID: 10822540 DOI: 10.1021/ol990027r] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[formula: see text] The lithiation of 2-methyloxazoles with alkyllithium and hindered lithium amide bases generally results in the competitive formation of a mixture of 5-lithio- and 2-(lithiomethyl)oxazole isomers. Herein a synthetically useful lithiation method which allows for the selective formation of 2-(lithiomethyl)oxazole is described. Diethylamine has been found to be a kinetically competent proton source that will mediate the equilibration of the kinetically formed 5-lithiooxazole to its more stable 2-(lithiomethyl)oxazole counterpart. Application of this metalation strategy with lithium diethylamide to two important bond constructions relevant to a projected phorboxazole synthesis is presented.
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Cornell M, Evans DA, Mann R, Fostier M, Flasza M, Monthatong M, Artavanis-Tsakonas S, Baron M. The Drosophila melanogaster Suppressor of deltex gene, a regulator of the Notch receptor signaling pathway, is an E3 class ubiquitin ligase. Genetics 1999; 152:567-76. [PMID: 10353900 PMCID: PMC1460625 DOI: 10.1093/genetics/152.2.567] [Citation(s) in RCA: 122] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
During development, the Notch receptor regulates many cell fate decisions by a signaling pathway that has been conserved during evolution. One positive regulator of Notch is Deltex, a cytoplasmic, zinc finger domain protein, which binds to the intracellular domain of Notch. Phenotypes resulting from mutations in deltex resemble loss-of-function Notch phenotypes and are suppressed by the mutation Suppressor of deltex [Su(dx)]. Homozygous Su(dx) mutations result in wing-vein phenotypes and interact genetically with Notch pathway genes. We have previously defined Su(dx) genetically as a negative regulator of Notch signaling. Here we present the molecular identification of the Su(dx) gene product. Su(dx) belongs to a family of E3 ubiquitin ligase proteins containing membrane-targeting C2 domains and WW domains that mediate protein-protein interactions through recognition of proline-rich peptide sequences. We have identified a seven-codon deletion in a Su(dx) mutant allele and we show that expression of Su(dx) cDNA rescues Su(dx) mutant phenotypes. Overexpression of Su(dx) also results in ectopic vein differentiation, wing margin loss, and wing growth phenotypes and enhances the phenotypes of loss-of-function mutations in Notch, evidence that supports the conclusion that Su(dx) has a role in the downregulation of Notch signaling.
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MESH Headings
- Amino Acid Sequence
- Animals
- Cloning, Molecular
- Drosophila Proteins
- Drosophila melanogaster/chemistry
- Drosophila melanogaster/enzymology
- Drosophila melanogaster/genetics
- Evolution, Molecular
- Gene Expression Regulation, Developmental
- Genes, Insect/genetics
- Genes, Suppressor/genetics
- Genetic Complementation Test
- Insect Proteins/genetics
- Ligases/genetics
- Membrane Proteins/physiology
- Molecular Sequence Data
- Mutation
- Phenotype
- Phylogeny
- Receptors, Cell Surface/physiology
- Receptors, Notch
- Sequence Alignment
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Signal Transduction
- Transfection
- Ubiquitin-Protein Ligases
- Wings, Animal/embryology
- Wings, Animal/growth & development
- Wings, Animal/metabolism
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Abstract
In recent years, epidemiologists have given increased attention to cognition, especially to the dementing illnesses that occur in old age. Central to this study is the measurement of change in cognition as opposed to cognition measured at a single point in time. This article addresses conceptual and methodological issues in the study of changes in cognitive function, including: 1) difficulties encountered with the use of single measurements of cognition and the importance of measuring changes in cognition; 2) sources of measurement variation and its potential effects; 3) the importance of careful modeling of age and education; 4) considerations in categorizing outcomes or combining the results of cognitive tests; and 5) the benefits of using multiple-outcome statistical models.
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Mendes de Leon CF, Glass TA, Beckett LA, Seeman TE, Evans DA, Berkman LF. Social networks and disability transitions across eight intervals of yearly data in the New Haven EPESE. J Gerontol B Psychol Sci Soc Sci 1999; 54:S162-72. [PMID: 10363047 DOI: 10.1093/geronb/54b.3.s162] [Citation(s) in RCA: 146] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVES There is considerable evidence that social networks are strongly related to survival and other health outcomes. However, findings regarding the effect of social networks on disability outcomes have been inconsistent. This study examines this relationship with respect to the risk of developing disability and recovering from disability. METHODS Data come from a community-based sample of the New Haven population aged 65 years and older, with nine annual interviews conducted between 1982 and 1991. Disability was measured by a 6-item index of activities of daily living (ADL), and a 3-item Rosow-Breslau index, with disability defined as impairment in one or more tasks on each measure. Social network variables were constructed for each of four domains of ties: children, relatives, friends, and a confidant, and a summary measure of total social networks. A Markov model was used to estimate one-year disability transitions averaged across all 8 intervals, after controlling for sociodemographic and health-related variables. RESULTS Total social networks was associated with a significantly reduced risk of developing ADL disability (beta = -0.009, p < .01), and a significantly increased likelihood of ADL recovery (beta = 0.017, p < .01). Emotional and instrumental support did not affect the protective effect of social networks against disability, but partially accounted for their effect on enhanced recovery. Network variables related to relatives and friends were significantly associated with disability and recovery risks, but those related to children or a confidant were not. The associations with disability transitions as measured by the Rosow-Breslau index were generally smaller and nonsignificant. DISCUSSION The findings lend further support for the role of social relationships in important health outcomes in old age. They suggest that being "embedded" in a social network of relatives and friends reduces risk for ADL disability, and enhances recovery from ADL disability.
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Wilson RS, Bennett DA, Beckett LA, Morris MC, Gilley DW, Bienias JL, Scherr PA, Evans DA. Cognitive activity in older persons from a geographically defined population. J Gerontol B Psychol Sci Soc Sci 1999; 54:P155-60. [PMID: 10363036 DOI: 10.1093/geronb/54b.3.p155] [Citation(s) in RCA: 153] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Patterns of cognitive activity, and their relation to cognitive function, were examined in a geographically defined, biracial population of persons aged 65 years and older. Persons (N = 6,162) were given cognitive performance tests and interviewed about their participation in common cognitive activities, like reading a newspaper. Overall, more frequent participation in cognitive activities was associated with younger age, more education, higher family income, female gender, and White race; participation in activities judged to be more cognitively intense was not strongly related to age, but was associated with more education, higher family income, male gender, and White race. Substantial heterogeneity in activity patterns remained after accounting for demographic factors, however. In an analysis controlling for demographic variables, level of cognitive function on performance tests was positively related to composite measures of the frequency and intensity of cognitive activity. Longitudinal studies are needed to assess the relation of cognitive activity patterns to stability and change in cognitive function in older persons.
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van Leeuwen FW, Verwer RW, Spence H, Evans DA, Burbach JP. The magnocellular neurons of the hypothalamo-neurohypophyseal system display remarkable neuropeptidergic phenotypes leading to novel insights in neuronal cell biology. PROGRESS IN BRAIN RESEARCH 1999; 119:115-26. [PMID: 10074784 DOI: 10.1016/s0079-6123(08)61565-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
For decades the magnocellular neurons of the hypothalamo-neurophypophyseal system (HNS), in which either vasopressin or oxytocin are produced and released into the bloodstream, have been playing a pivotal role in fundamental discoveries in the nervous system. The primary structure of vasopressin and oxytocin was the first of all neuropeptides to be published, i.e., in the 1950s by the Nobel prize laureate Du Vigneaud. Moreover, many trend-setting discoveries have their origin in the HNS, which abundantly expresses vasopressin and oxytocin, clearly displays its function and is relatively easily to manipulate. Examples are the phenomenon of coexpression of neuropeptides, patch-clamping of nerve endings, axonal transport of RNA, neuroglia interactions and the behavioral effects. An extraordinarily intriguing example is the homozygous Brattleboro rat, which lacks vasopressin by a germ-line mutation, and has disclosed many of the fundamental characteristics of peptidergic neurons, and neurons in general. In this chapter we will discuss a few of them, in particular the recent data on mutations in vasopressin RNA. It is to be expected that the HNS will retain its informative role in the next decades.
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Glynn RJ, Beckett LA, Hebert LE, Morris MC, Scherr PA, Evans DA. Current and remote blood pressure and cognitive decline. JAMA 1999; 281:438-45. [PMID: 9952204 DOI: 10.1001/jama.281.5.438] [Citation(s) in RCA: 188] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT Previous studies raise the possibility that blood pressure (BP) in middle age predicts later cognitive decline. OBJECTIVE To examine prospectively the relationship of BP with level of and change in cognitive function in the elderly. DESIGN Longitudinal, population-based study comprising subjects enrolled in the East Boston component of the Established Populations for the Epidemiologic Study of the Elderly (EPESE) (1982-1983) and the Hypertension Detection and Follow-Up Program (HDFP) (1973-1974). SETTING East Boston, Mass. PARTICIPANTS Of the 3657 participants in the EPESE with baseline BP measurements, 2068 also participated in the HDFP. Subjects were aged 65 to 102 years at baseline in the EPESE and had mental status and memory assessed at baseline and 3 and 6 years. MAIN OUTCOME MEASURES Numbers of errors on the Short Portable Mental Status Questionnaire and the East Boston Memory Test and rates of change in these numbers of errors. Subjects had BP measured both at baseline in the EPESE and 9 years before, as part of the HDFP. RESULTS In analyses adjusted for age, sex, and education, there was no strong linear association between BP and cognition. The associations found were fairly small in magnitude, and varied according to which test was used to measure cognition. There was little evidence for an effect of BP on change in cognitive function with either test, or for an effect on level of function on the memory test. In analyses of level of mental status questionnaire performance, however, elevated systolic BP (> or =160 mm Hg) 9 years before baseline was associated with a 14% (95% confidence interval [CI], 4%-25%) increase in error rate, relative to the referent (130-139 mm Hg). Baseline systolic BP had a U-shaped association with the number of errors; error rates were 9% higher compared with the referent group among those with systolic BP lower than 130 mm Hg (95% CI, 1%-17%) and 7% greater (95% CI, 0%-15%) among those with elevated systolic BP. Diastolic BP 9 years before baseline also had a U-shaped association with errors on the mental status questionnaire. CONCLUSION The findings do not suggest a linear association of BP with cognitive decline, but they are consistent with a more complex relationship between BP and cognition than previously appreciated.
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