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Richard Schulz

Publications and source records attributed to Richard Schulz.

101 records · Page 6Linked to original sources

Nitrate tolerance does not increase production of peroxynitrite in the heart.

Clinical studies have suggested that long-term nitrate treatment does not improve and may even worsen cardiovascular mortality, and the possible role of nitrate tolerance has been suspected. Nitrate tolerance has been recently shown to increase vascular superoxide and peroxynitrite production leading to vascular dysfunction. Nevertheless, nitrates exert direct cardiac effects independent from their vascular actions. Therefore, we investigated whether in vivo nitroglycerin treatment leading to vascular nitrate tolerance increases cardiac formation of nitric oxide (NO), reactive oxygen species, and peroxynitrite, thereby leading to cardiac dysfunction. Nitrate tolerance increased bioavailability of NO in the heart without increasing formation of reactive oxygen species. Despite elevated myocardial NO, neither cardiac markers of peroxynitrite formation nor cardiac mechanical function were affected by nitroglycerin treatment. However, serum free nitrotyrosine, a marker for systemic peroxynitrite formation, was significantly elevated in nitroglycerin-treated animals. This is the first demonstration that, although the systemic effects of nitroglycerin may be deleterious due to enhancement of extracardiac peroxynitrite formation, nitroglycerin does not result in oxidative damage in the heart.

Animals↗

Cardiomyocyte overexpression of iNOS in mice results in peroxynitrite generation, heart block, and sudden death.

Increased inducible nitric oxide synthase (iNOS) expression is a component of the immune response and has been demonstrated in cardiomyocytes in septic shock, myocarditis, transplant rejection, ischemia, and dilated cardiomyopathy. To explore whether the consequences of such expression are adaptive or pathogenic, we have generated a transgenic mouse model conditionally targeting the expression of a human iNOS cDNA to myocardium. Chronic cardiac-specific upregulation of iNOS in transgenic mice led to increased production of peroxynitrite. This was associated with a mild inflammatory cell infiltrate, cardiac fibrosis, hypertrophy, and dilatation. While iNOS-overexpressing mice infrequently developed overt heart failure, they displayed a high incidence of sudden cardiac death due to bradyarrhythmia. This dramatic cardiac phenotype was rescued by specific attenuation of transgene activity. These data implicate cardiomyocyte iNOS overexpression as sufficient to cause cardiomyopathy, bradyarrhythmia, and sudden cardiac death.

Acetylcholinesterase↗

Social support as a mediator in the relation between functional status and quality of life in older adults.

The relations among physical functioning, social support, depressive symptoms, and life satisfaction were examined in a national sample of 4,734 adults age 65 and older. Regression analyses were used to examine the relative importance of objective and subjective support measures in understanding the relation between physical impairment and quality of life. Impairment was associated with fewer friendship contacts, fewer family contacts, less perceived belonging support, and less perceived tangible aid, but only measures of perceived support predicted depressive symptomatology. A structural equation modeling approach was then used to explore the mediational role of perceived social support in the relation between impairment and quality of life variables. Results are consistent with the hypothesis that lower reported social support is an important reason for decreases in life satisfaction and increases in depressive symptoms found among older adult populations. Implications for understanding the role of social support in attenuating the effects of physical disability in older adults are discussed.

Activities of Daily Living↗

Guidelines for conducting geropsychotherapy research.

Geropsychotherapy researchers have established specific methods that improve the reliability and generalizability of the data from this research. To date, there has been little formal dissemination of these methods. The authors present guidelines for the optimal conduct of psychotherapy research in older adults, which include selection of age-appropriate psychotherapies and control conditions, use of consumer-based methods for recruitment, evaluation of age-related treatment processes and outcomes, and adjusting the research design to accommodate age-specific life events and provide examples of how each guideline was used in their psychotherapy studies. Psychotherapy research with older adults has benefited from methodological advances that improve our ability to ascertain the impact of psychotherapy on late-life disorders. However, the field is still in need of better outcome and process measures, methods for measuring the therapeutic content of non-psychotherapy encounters, and methods for determining the impact of choice of treatment on outcome.

Aged↗

Family caregiving of persons with dementia: prevalence, health effects, and support strategies.

The authors summarize the dementia caregiving literature and provide recommendations regarding practice guidelines for health professionals working with caregivers. Family caregiving of older persons with disability has become commonplace in the United States because of increases in life expectancy and the aging of the population, with resulting higher prevalence of chronic diseases and associated disabilities, increased constraints in healthcare reimbursement, and advances in medical technology. As a result, family members are increasingly being asked to perform complex tasks similar to those carried out by paid health or social service providers, often at great cost to their own well-being and great benefit to their relatives and society as a whole. The public health significance of caregiving has spawned an extensive literature in this area, much of it focused on dementia caregiving because of the unique and extreme challenges associated with caring for someone with cognitive impairment. This article summarizes the literature on dementia caregiving, identifies key issues and major findings regarding the definition and prevalence of caregiving, describes the psychiatric and physical health effects of caregiving, and reviews various intervention approaches to improving caregiver burden, depression, and quality of life. Authors review practice guidelines and recommendations for healthcare providers in light of the empirical literature on family caregiving.

Aged↗

Use of cognitive enhancement medication in persons with Alzheimer disease who have a family caregiver: results from the Resources for Enhancing Alzheimer's Caregiver Health (REACH) project.

OBJECTIVE: Aging populations show increased prevalence of cognitive impairment and dementia. Recent efficacy studies report on prescription medications and herbal preparations that affect cognitive functioning, but the prevalence and correlates of cognitive-enhancement (CE) medication use among community-dwelling older persons is not well studied. The authors examined the frequency and appropriateness of use, the importance of a family caregiver in medication decisions for dementia patients, and differences in access to medical care. METHODS: REACH is a multisite feasibility study of several approaches to reducing the negative impacts of caregiving on those living with a family member with dementia. Data on medication use by care-recipients were collected at baseline and 1 year later. RESULTS: At baseline, 31% of 1,222 care-recipients were using a CE medication. Factors independently related to CE use were age, education, functional status, and caregiver vigilance. Within 1 year, 14% started and 30% quit taking CE. Care-recipients more likely to be Starters had spouse-caregivers, more education, and fewer baseline ADL impairments. Quitters had more ADL deficits at baseline and became less able to perform ADL at follow-up than those who continued on CE. CONCLUSIONS: CE medication use among dementia patients with a family caregiver is relatively common, though there is substantial geographic variability. Our findings are mixed with respect to appropriate use of CE medications, suggesting areas for physician education. Our data indicate the importance of the caregiver in CE medication use and suggest that there may be disparities in access to healthcare among people with cognitive impairment.

Adult↗