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D Reed

Publications and source records attributed to D Reed.

At least 37 records · Page 2Linked to original sources
PubMed1997

Personality, social networks, and perceived social support among alcoholics: a structural equation analysis.

In this study we tested relations among personality characteristics, social network properties, and perceived social support both concurrently and prospectively. A sample of 294 men in treatment at a Department of Veterans Affairs Alcohol Treatment Unit was assessed during treatment and 3 months after discharge. Results of the cross-sectional structural equation analyses indicated that the personality characteristics of extraversion and neuroticism were related to both social network properties and perceived social support. Characteristics of the alcoholic's social network were also related to perceived availability of support. Longitudinal analyses of perceived social support after treatment indicated that two social network properties (size of the network and the proportion of confidants) were predictive net of initial levels of social support. Extraversion and neuroticism were found to be indirectly related to perceived social support at Time 2 through their effects on social network properties and perceived social support during treatment. Implications of these findings for models of the nature and determinants of perceived social support are discussed.

Adaptation, Psychological↗
PubMed1997

Morphometric description of the wandering behavior in Drosophila larvae: aberrant locomotion in Na+ and K+ channel mutants revealed by computer-assisted motion analysis.

Wandering is a simple behavior in Drosophila larvae prior to metamorphosis. Using the Dynamic Image Analysis System (DIAS) initially developed for analyzing amoeboic movements of single cells, we have analyzed videotaped behaviors of Drosophila larvae at the wandering stage. Previous studies show that mutations in the Na+ channel gene paralytic (para) cause paralysis at 29 degrees C, and mutations in the K+ channel beta subunit gene Hyperkinetic (Hk) lead to leg-shaking under ether anesthesia. The application of DIAS revealed quantifiable abnormalities in the larval locomotion of both ion channel mutants even under "permissive" conditions. Analysis of centroid movement indicates that, compared to wild type, both Hk and para larvae crawled at a slower average speed, but a similar peak instantaneous speed during a contraction cycle. Nevertheless, contraction in the body length was greater in mutants, implying a lower efficiency in conversion of muscular contraction to distance translocation. In addition, each mutant produced a characteristic crawling pattern distinct from the wild-type control. The larval crawling pattern was determined by periods of linear locomotion interposed by non-locomotive, "searching and decision-making" episodes, after which the crawling was resumed in a new direction. Our results demonstrate that mutations in single ion channel subunits resulted in stereotypic modifications in locomotion control and crawling patterns, and that DIAS is a powerful tool in revealing subtle differences in animal behavior and quantifying mutational effects on the interplay of discrete behavioral components.

Animals↗
PubMed1997

Assessing family and staff caregiver outcomes in Alzheimer disease research.

Outcomes and measurement issues related to caregivers for persons with Alzheimer disease and related disorders are examined. Assumptions regarding the dynamic linkages between resident, family, and staff outcomes are reviewed, and potential sources of stress inherent in family adaptation to the institutional setting, role transitions, and emotional responses that occur with placement are examined. Family and staff caregiver outcomes that flow logically from treatment goals, and what can be expected if sources of transitional and institutional stress are ameliorated through successful family and staff-related interventions, are discussed. Instruments developed to evaluate family perceptions of care and the caregiving role in institutional settings are described. The article concludes with an analysis of measurement approaches, general measurement issues, and those more specific to family and staff caregivers, as well as recommendations for further development in this area.

Alzheimer Disease↗
PubMed1997

Hydroxyapatite-oil composites for delivering AZT in simulated body fluid.

Hydroxyapatite (HA) has been used to deliver therapeutic drugs both in vitro and in vivo at a constant rate showing zero order kinetics. This study was designed specifically to analyze the effects of wheat germ (WG) incorporation with HA on the rate of delivery of AZT from an insert system over a one month period in vitro. Insert systems which were saturated with wheat germ oil delivered AZT at a slower rate over the one month period than did half-saturated or unsaturated insert systems. All systems containing 50 mg of AZT in the outer shell delivered 80% of the 100 mg AZT dosage over the first eight days. The systems which had a 100 mg AZT insert surrounded by an oily HA shell lacking AZT delivered AZT in a linear manner over the course of one month. The amounts and rates of AZT release from composites was indirectly proportional to the amount of wheat germ oil used. The results of this study show that the lipids incorporated in the ceramic composites can be tailored to deliver a 100 mg AZT dosage for a period of one month in vitro.

Anti-HIV Agents↗
PubMed1997

Parameters of protein delivery using hydroxyapatite in simulated body fluid.

Various studies have been conducted using hydroxyapatite (HA) to deliver therapeutic drugs over a long period of time. However, the rate of drug release from ceramics varies tremendously. Thus a study was designed to observe the effect of particle size, pressure, drug ratio, and the addition of a zinc stearate binder on the release of BSA from ceramics. Samples were collected every two hours for a 12 hour period. Three particle sizes were used in the study (< 38, 45-63, and 63-75 microns). Variations in particle size did not influence the release of BSA. Ceramics compressed at a pressure of 150 Mpa delivered more protein than pressures of 300 MPa, 450 MPa, and 900 MPa. Drug to ceramic ratio had the most significant effect. A ratio of 1:25 BSA to HA delivered the protein quickly whereas the 1:100 BSA to HA delivered BSA to HA delivered BSA slowly and in zero order kinetics. The addition of the zinc binder improved the quality of the composite and decreased the release rate of protein delivery when present in 5% or less of the total ceramic weight. HA ceramics can be used to deliver proteins at different rates by varying compression pressure and drug to HA ratio.

Biocompatible Materials↗
PubMed1996

Evidence against the operation of selective mortality in explaining the association between cigarette smoking and reduced occurrence of idiopathic Parkinson disease.

To investigate the association between idiopathic Parkinson disease (IPD) and reduced frequency of prior cigarette smoking, the authors compared the 29-year follow-up mortality rates and IPD incidence rates of men who were either cigarette smokers or nonsmokers at the time of enrollment in the Honolulu Heart Study (1965-1968). Based on IPD cases detected up to June 30, 1994, the age-adjusted incidence rate in smokers was less than half that in nonsmokers: 34.4 versus 94.2 cases per 100,000 person-years of pre-illness follow-up, respectively. When data were stratified by 5-year age group, lower IPD incidence in smokers was observed at all ages between 50 and 90 years. Age-specific mortality trends for smokers and nonsmokers with and without IPD suggested that increased mortality in IPD patients was mostly associated with IPD itself and not with smoking. The slight excess mortality in smokers without IPD, versus nonsmokers without IPD, appeared insufficient to account for the "missing" incident IPD cases in smokers. These IPD incidence and mortality data are not highly consistent with the "selective mortality" hypothesis, which attributes reduced prior smoking frequency, typically reported by persons with IPD, to accelerated mortality in undiagnosed IPD-affected persons who smoke. The "protective" association of cigarette smoking with IPD occurrence may thus be real, suggesting the need for further study of biologic mechanisms of protection.

Age Distribution↗
PubMed1996

The relationship of social cognition to ward behavior in chronic schizophrenia.

The relationship between social cognition (i.e., cognition for social stimuli) and ward behavior among individuals with chronic schizophrenia was investigated. Twenty-seven inpatients completed a battery of cognitive and social-cognitive tasks and were rated by staff on various indices of ward behavior. Overall, there was a relationship between the measures of social cognition and behavior on the ward. Social cognition contributed unique variance beyond cognition to maladaptive behavior on the ward (i.e., irritability). Implications for assessment and future research are discussed.

Adult↗
PubMed1996

Supertasting, earaches and head injury: genetics and pathology alter our taste worlds.

Family studies using thresholds showed that PROP (6-n-propylthiouracil) tasting is produced by a dominant allele, T. Nontasters have two recessive alleles and tasters have one or two dominant alleles. The bitterness of suprathreshold PROP and anatomical criteria subdivide tasters into medium and supertasters. Supertasters may be TT tasters, but this has yet to be demonstrated. Supertasters preceive the greatest bitterness and sweetness from many stimuli as well as the greatest oral burn from alcohol and capsaicin. Women are more likely than men to be supertasters. Otitis media and head trauma can alter taste and thus PROP classifications, complicating studies on PROP genetics. Some subjects with a history of otitis media show taste reductions, but others show enhanced tastes and appear to have more taste buds per fungiform papilla. Subjects with head trauma show reduced tastes on some oral loci, but there is evidence that severe reductions on the front of the tongue ameliorate reductions at the circumvallate papillae on the back of the tongue by a release of inhibition mechanism.

Brain Injuries↗
PubMed1996

Quantitation of passively acquired human immunodeficiency virus (HIV) antibodies in AIDS patients transfused with a plasma that is rich in HIV antibodies.

BACKGROUND: Passive immunotherapy in human immunodeficiency virus (HIV) infection is based on transfusions of plasma that is rich in HIV antibodies. STUDY DESIGN AND METHODS: To verify whether the clearance of transfused antibodies will maintain an elevated titer of specific antibodies between biweekly transfusions of plasma, the titers of anti-HIV-1 in plasma and in transfusion recipients were measured. Samples from 12 recipients were analyzed by automated scanning of Western blot, before transfusion and at Days 2, 7, and 14 after transfusion. RESULTS: The p24 antibody became detectable or higher than the baseline after transfusion and remained detectable until the second transfusion. Anti-p24 titers were variable and dependent on the antibody titer of the transfused plasma and the baseline p24 antigen titer. CONCLUSION: Biweekly transfusion of plasma with a high anti-HIV titer maintains a high anti-p24 titer between transfusions in AIDS patients treated with passive immunotherapy.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Imbalance in an older population: an epidemiological analysis.

Difficulties with balance are associated with limitations in activities of daily living. There is little information, however, about the epidemiology of imbalance. Imbalance, defined as the inability to maintain a full-tandem stand for 10 seconds, was assessed as part of an interview with 2,018 residents of Marin County, California, age 55 and older. The likelihood of imbalance was greater in women, those aged 85 and older, and those with less than 12 years of education. It was also associated with specific chronic conditions, including a history of hypertension, stroke, or cataracts. Even after adjusting for these conditions, imbalance was associated with reduced lower-body strength as well as poor short-term memory, hip pain, vision problems, abstention from alcohol, and current cigarette smoking. With those aged 85 and older representing the fastest growing age group in developed nations, imbalance may become a major health problem.

Activities of Daily Living↗
PubMed1995

Nonsteroidal antiinflammatory drugs cause apoptosis and induce cyclooxygenases in chicken embryo fibroblasts.

Programmed cell death (apoptosis) is an intrinsic part of organismal development and aging. Here we report that many nonsteroidal antiinflammatory drugs (NSAIDs) cause apoptosis when applied to v-src-transformed chicken embryo fibroblasts (CEFs). Cell death was characterized by morphological changes, the induction of tissue transglutaminase, and autodigestion of DNA. Dexamethasone, a repressor of cyclooxygenase (COX) 2, neither induced apoptosis nor altered the NSAID effect. Prostaglandin E2, the primary eicosanoid made by CEFs, also failed to inhibit apoptosis. Expression of the protooncogene bcl-2 is very low in CEFs and is not altered by NSAID treatment. In contrast, p20, a protein that may protect against apoptosis when fibroblasts enter G0 phase, was strongly repressed. The NSAID concentrations used here transiently inhibit COXs. Nevertheless, COX-1 and COX-2 mRNAs and COX-2 protein were induced. In some cell types, then, chronic NSAID treatment may lead to increased, rather than decreased, COX activity and, thus, exacerbate prostaglandin-mediated inflammatory effects. The COX-2 transcript is a partially spliced and nonfunctional form previously described. Thus, these findings suggest that COXs and their products play key roles in preventing apoptosis in CEFs and perhaps other cell types.

Animals↗
PubMed1995

Correlation between viral DNA load and serum anti p19 antibody concentration in symptomless human T-lymphotropic virus type-I (HTLV-I)-infected individuals.

In order to determine whether serum anti-human T-cell lymphotropic virus type I (HTLV-I) antibody concentration is correlated with cellular viral DNA load, these 2 biological parameters were established in 22 symptomless HTLV-I carriers. The proviral copy (PVC) number was determined through quantificative polymerase chain reaction. Specific antibody titers were determined by Western blot with the end-point dilution method; the quantification of each antibody was performed through ScanBlot by determination of the peak height of each Western-blot band. A positive correlation was observed between the PVC number and the titer of total antibodies. When the association between the peak height of each antibody and the PVC number was studied, a significant positive correlation was observed only with anti-p 19. Further evaluation through follow-up studies of symptomless HTLV-I individuals is needed to clarify the value of anti-HTLV-I antibody titer as a predictor of disease progression.

Adult↗
PubMed1995

Women's self-disclosure of HIV infection: rates, reasons, and reactions.

A survey of 65 ethnically diverse women at 2 outpatient HIV clinics revealed relatively low rates of disclosure of HIV-positive serostatus to extended family members, somewhat higher rates for immediate family members, and highest rates for lovers and friends. Spanish-speaking Latinas were less likely to disclose their serostatus or to discuss HIV-related worries with others than English-speaking Latinas, African Americans, and Anglo Americans. Reasons for disclosure and nondisclosure varied by target. In general, targets reacted positively to disclosure. Implications for clinicians treating women with HIV infection are discussed.

Adolescent↗
PubMed1995

Performance of the Coumatrak system in a large anticoagulation clinic.

There is a need to monitor anticoagulation accurately, inexpensively, and rapidly. The accuracy and precision of a simple fingerstick method was studied in a large outpatient anticoagulation clinic using the Coumatrak method. The Coumatrak apparatus has been studied in the home setting, and three recent reports suggest that it is practical, accurate, and possibly superior to the standard method. These results differ from recently published studies. This technique was found to be less than acceptable in precision and accuracy. This method requires further study before it can be recommended for wide-spread use in making decisions for patient care.

Adult↗
PubMed1995

Health and functioning among the elderly of Marin County, California: a glimpse of the future.

BACKGROUND: The purpose of this study was to obtain information concerning the health status of the theoretically advantaged elderly population of Marin County, California, and to compare these data with those from other populations with different levels of socioeconomic status. METHODS: An age-stratified sample of 2,018 community-dwelling elderly residents of Marin was selected, and these participants were interviewed between 1989 and 1991. Interview items included medical history of life-threatening diseases and chronic conditions, reported and observed disabilities, and life-style characteristics. RESULTS: While the residents of Marin had lower mortality rates than the total U.S. population, there were few meaningful differences in measures of health and function in comparison to other elderly populations with substantially lower levels of socioeconomic status. The main exceptions were better memory performance and lower depressive symptomatology in Marin. Because of the many methodological differences, these comparisons must be viewed with caution. CONCLUSION: The general pattern of findings in this study indicates that while death has been postponed in this socioeconomically advantaged population, the prevalence of disease and disability has not. If true, this implies that residents of an affluent community can spend a longer rather than shorter period of their late life in a state of infirmity and in need of medical care. This appears to be especially true for women.

Activities of Daily Living↗
PubMed1995

Information processing and social competence in chronic schizophrenia.

The relationship between social competence and information processing among individuals with chronic schizophrenia was investigated. Thirty-eight inpatients participated in a role play test of social competence and completed a battery of information-processing tasks. Information processing was found to be significantly related to social competence, even after controlling for patient demographics, chronicity, and symptomatology. Higher global social competence was related to more efficient early information processing on a continuous performance/span of apprehension task. Composite indices of specific social competence (i.e., paralinguistic and nonverbal skills) were related to other aspects of information processing (e.g., reaction time). Implications for behavioral assessment and cognitive rehabilitation are discussed.

Adult↗
PubMed1995

Cigarette smoking and protection from Parkinson's disease: false association or etiologic clue?

We reviewed 46 published reports associating cigarette smoking and Parkinson's disease. Although the majority indicated an approximate halving of smoking frequency in persons with Parkinson's disease, many observers have suggested that the effect could be a spurious result. That the association may be real is suggested by at least six observations: (1) the consistency of findings between independent studies of different design, conducted by different investigators, in different nations, over 35 years; (2) the association's predominance and strength in prospective studies; (3) the apparent detection of a dose-response relation; (4) the inability to explain the association by confounding variables; (5) the flaws in certain arguments against the association's validity; and (6) the identification of a similar association, of similar magnitude, between smoking and reduced occurrence of Alzheimer's disease. A protective association of cigarette smoking for Parkinson's disease may constitute an important etiologic clue.

Female↗