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S McGuinness

Publications and source records attributed to S McGuinness.

8 recordsLinked to original sources
PubMed1996

Learned helplessness in the multiple sclerosis population.

The purpose of this cross-sectional, descriptive study was to describe the relationships between learned helplessness and disease status, functional and social disability, and disease activity in the multiple sclerosis population. Additionally, the relationships between learned helplessness and age, disease duration, education and marital and employment status were evaluated. Self-report instruments with established validity and reliability in the multiple sclerosis population were used to collect the data. Learned helplessness was significantly positively correlated with social and functional disability. Although not significant at the .05 level, disease status and disease activity were also positively correlated with learned helplessness. Additionally, unemployed individuals were more likely to be helpless than employed individuals. Overall, the results suggest that learned helplessness is related to negative health indicators in the multiple sclerosis population. Nursing interventions to decrease or prevent learned helplessness may be appropriate in this population.

Activities of Daily Living↗
PubMed1995

Vasopressin resistance in chronic renal failure. Evidence for the role of decreased V2 receptor mRNA.

Studies were performed to determine the mechanism underlying deficient arginine vasopressin (AVP)-stimulated adenylyl cyclase activity in chronic renal failure (CRF). As compared to control, principal cells cultured from the inner medullary collecting tubule of rats previously made uremic by 5/6 nephrectomy fail to accumulate cAMP when stimulated with AVP. CRF cells do respond normally to forskolin or cholera toxin and the defect in AVP responsiveness is not prevented by treatment with pertussis toxin, by cyclooxygenase inhibition, or by inhibition or down-regulation of protein kinase C. In contrast to their lack of responsiveness to AVP, CRF cells respond normally to other agonists of adenylyl cyclase such as isoproterenol or prostaglandin E2. Plasma membranes prepared from the inner medullae of CRF rats exhibit a marked decrease in apparent AVP receptor number but no change in the apparent number of beta adrenergic receptors. Reverse transcriptase PCR of total RNA from the inner medullae of CRF animals reveals virtual absence of V2 receptor mRNA; mRNA for alpha s is present in normal abundance. These studies indicate that AVP resistance in CRF is due, at least in part, to selective down-regulation of the V2 receptor as a consequence of decreased V2 receptor mRNA.

Animals↗
PubMed1993

Examination of the structure-toxicity relationships of L-cysteine-S-conjugates of halogenated alkenes and their corresponding mercapturic acids in rat renal tissue slices.

Rat kidney slices were produced using a modified version of a mechanical tissue slicer. The slices were incubated with various concentrations of L-cysteine conjugates and mercapturic acids of halogenated alkenes in a submersion incubation system. The slices showed a time- and concentration-dependent toxicity to the nephrotoxic conjugates. The five L-cysteine conjugates tested: S-(1,2-dichlorovinyl)-L-cysteine (1,2-DCVC), S-(1,1,2,2-tetrafluoroethyl)-L-cysteine (TFEC), S-(1-chloro-1,2,2-trifluoroethyl)-L-cysteine (CTFEC), S-(1,1-dichloro-2,2-difluoroethyl)-L-cysteine (DCDFEC) and S-(1,1-dibromo-2,2-difluoroethyl)-L-cysteine (DBDFEC) were more toxic compared to the corresponding mercapturic acids. Comparing the in vitro toxicity data with the in vivo data for the same compounds results in similar ranking for the relative nephrotoxicity of the conjugates.

Acetylcysteine↗
PubMedDate not supplied

Responding to reported clusters of common diseases: the case of multiple sclerosis.

Reports of disease clustering are becoming ever more common, and there is increasing pressure on public health agencies to respond rapidly and appropriately to these reports. We investigated a cluster of five cases of MS occurring in a small multidisciplinary hospital department. Data were collected by a variety of methods, including measurement and description of the workplace, completion of survey instruments by department staff, and construction of case histories of persons with MS. The results indicated that the department comprised a high-risk population and that only one case of MS could have any possible etiologic significance. Investigators should consider a number of factors when evaluating disease clusters, including the accuracy of diagnosis, the induction period and cause of the disease, and possible biases in the population at risk. Additionally, boundaries should not encircle the cases that led to identification of the cluster and should reflect environmental significance.

Adult↗