PubMed Health⌕ Search

Biomedical subjects

C A Cook

Publications and source records attributed to C A Cook.

At least 37 records · Page 2Linked to original sources
PubMed1993

Comparison of the efficacy and metabolic effects of nicardipine and hydrochlorothiazide in hypertensive black men and women.

A double-blind, randomised, parallel study compared the BP and metabolic responses in black hypertensive patients following monotherapy with nicardipine or hydrochlorothiazide (HCTZ). Following a single-blind placebo wash-out period of 1-4 weeks, the study drug, nicardipine 20-40 mg three times daily or HCTZ 25-100 mg four times daily, was administered in a double-blind fashion for 12 weeks. Doses were titrated to control sitting DBP (< or = 90 mmHg). Both drugs were effective in reducing sitting SBP and DBP as compared with baseline values (nicardipine: 152.5 +/- 1.6/102.0 +/- 0.6, HCTZ: 152.5 +/- 1.5/101.4 +/- 0.5 mmHg). DBP responses (reduction from baseline; nicardipine: -10.9, HCTZ: -12.7 mmHg), and the percentage of patients achieving a response < or = 90 mmHg (nicardipine: 54%, HCTZ: 63%) to the two drugs were similar. Although SBPs at baseline and endpoint (137.3 +/- 1.6 on nicardipine and 132.1 +/- 1.4 mmHg on HCTZ), and the percentage of patients achieving a response < or = 140 mmHg (nicardipine: 70%, HCTZ: 79%), were comparable between the two treatments, the SBP reduction with HCTZ was statistically greater (P = 0.026). A comparison of the metabolic responses in the two treatment groups showed significant differences. Nicardipine caused no significant changes in blood chemistry, whereas HCTZ caused statistically significant decreases (P < 0.001) in sodium and potassium and increases (P < or = 0.01) in glucose, BUN, creatinine, uric acid, cholesterol and LDL compared with baseline. In 12.7% of the patients in the HCTZ group, serum potassium dropped to levels < 3.5 meq/l, which occurred in only 1.4% of the patients who used nicardipine.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Utilization of outpatient mental health services after inpatient alcoholism treatment.

It is generally agreed that use of aftercare services following discharge from alcoholism treatment is optimum for patients to achieve long-term recovery. However, the quantity and duration of utilization of such services in non-experimental settings are generally unknown. Using secondary data sources, we studied 5,635 alcoholics completing formal extended inpatient treatment and 1,860 alcoholics discharged from brief inpatient hospitalizations in Department of Veterans Affairs medical centers. Weekly use of outpatient mental health services (OPMH) prior to hospital admission was equally low for both patient groups (approximately 2-3% of patients) until four weeks prior to admission, at which time OPMH use increased, particularly for the extended treatment group. In the four weeks after discharge, use of OPMH services was substantially higher for patients with extended treatment compared to those with brief hospitalizations (40% vs. 18%), with 22% of patients completing treatment utilizing such services in the first week after discharge. Utilization steadily decreased until only 8% and 4% of both groups, respectively, were using OPMH services at the end of six months after discharge. Study results suggest the need to examine barriers to outpatient mental health utilization after discharge as well as interventions to increase compliance with long-term aftercare.

Adult↗
PubMed1992

Alcoholism treatment, severity of alcohol-related medical complications, and health services utilization.

In efforts to contain costs and efficiently allocate resources, evaluation studies in alcoholism have increasingly assessed the effect of treatment on the use of health services through comparisons of treated and untreated alcoholics. The success of this approach requires that evaluators identify and adjust for differences between these two groups, thereby decreasing the likelihood that health utilization outcomes are attributed to the effects of treatment when in fact they may be related more to unidentified group differences. Using a sample of 63,873 hospitalized alcoholics, this study focused on one critical group difference, the severity of alcohol-related medical complications. Comparisons between treated alcoholics who either completed alcoholism treatment or detoxification only and untreated alcoholics with either primary medical/surgical or psychiatric diagnoses demonstrated the following: (a) untreated alcoholics with medical/surgical diagnoses were more likely to have severe alcohol-related medical complications than the other groups; (b) a positive linear relationship between health services utilization in the previous year and the severity of medical complications existed for all groups, except untreated alcoholics with psychiatric diagnoses; and (c) untreated alcoholics with psychiatric diagnoses with the most severe complications used fewer health services than any of the other three groups. Differences between treated and untreated alcoholics in both severity of medical complications and previous health utilization patterns demonstrate the need to identify and adjust for these factors in evaluation studies that examine the outcomes of alcoholism treatment.

Adult↗
PubMed1992

Research in social work practice: benefits of and obstacles to implementation in the Department of Veterans Affairs.

Although research is an important part of social work practice in health care, there is little systematic information that sheds light on research productivity, the benefits of conducting research, or the obstacles that must be overcome. This article represents the viewpoints of nearly all the directors of social services departments in the largest multihospital system in the United States, the Department of Veterans Affairs. The organizational characteristics of hospitals and the attitudes of the directors about research were important correlates of research productivity. Although lack of time, resources, and interest were cited as common obstacles, more than one-third of the departments were conducting or involved in at least one study. Information about the research efforts of other social services departments was considered an important resource, particularly for departments with no ongoing studies. The implications of these findings for social work research in health care are discussed.

Attitude↗
PubMed1992

Age and ethnicity among hospitalized alcoholics: a nationwide study.

Little is known about the broad-scale demographic characteristics of low income or indigent alcoholics in public hospital systems. The purpose of the study was to examine issues relative to age, race/ethnicity, and marital status for a large group (n = 62,829) of alcoholic men receiving inpatient care in Department of Veterans Affairs (VA) medical centers nationally. Subjects were VA inpatients completing alcoholism treatment (n = 27,562), in brief alcohol detoxification or short intervention (n = 9,322), or hospitalized for primary diagnoses other than alcoholism but with a secondary diagnosis of alcohol dependence syndrome (n = 25,945). Minority alcoholics were significantly younger than Caucasian alcoholics. Hispanic and African-American men, as well as older alcoholics, were significantly less likely to complete treatment or attend detoxification and more likely to be hospitalized for other primary diagnoses. Native Americans, however, were most likely to complete alcoholism treatment. Results suggest that members of some minority groups and elderly alcoholics seek inpatient care for diagnoses other than alcoholism and that, as a result, such individuals may need targeted interventions to encourage them to seek alcohol-specific care.

Adult↗
PubMed1992

Age-related psychiatric comorbidities and level of functioning in alcoholic veterans seeking outpatient treatment.

The relationship of age and of level of adaptive functioning to comorbidity of mental disorders among alcoholics was studied in a survey of all alcoholics seeking outpatient mental health treatment in the Veterans Affairs mental health care system during a one-month period in 1986 (N = 22,463). More than half of the alcoholic outpatients had one or more comorbid psychiatric diagnoses. Rates for comorbid substance abuse disorders, posttraumatic stress disorder, schizophrenia, and personality disorders peaked in younger alcoholics and then decreased with age. Age-related increases were observed for major depression, anxiety disorders, and organic brain syndrome or dementia. DSM-III axis V ratings of poor to grossly impaired functioning were consistent across age groups. More than half of alcoholics with a comorbid psychiatric disorder were rated as severely impaired, compared with less than a third of those with no comorbid mental disorder.

Activities of Daily Living↗
PubMed1992

High social risk screening mechanisms: patient characteristics as predictors of social work utilization in the VA.

To facilitate timely access to social services in hospitals, high social risk (HSR) screening mechanisms have been implemented throughout the country. The purpose of these mechanisms is to identify patients upon admission who are most likely to need service. Because these screening mechanisms often identify patients who do not need service, this study determined how well the patient characteristics used as screening factors actually predicted service utilization. A multivariate logistic regression model was developed using 1,659 discharges from two midwestern hospitals. The most powerful predictors of social service use were age, multi-system illness, not having a spouse, and psychiatric co-morbidity. Despite the significant contribution of each predictor, their combined ability to predict who receives service was modest.

Activities of Daily Living↗
PubMed1991

Ethical dilemmas in driver reeducation.

This article illustrates ethical dilemmas faced by therapists who provide driver reeducation. The dilemmas discussed are (a) accepting a wide range of referral sources and client disabilities versus the inability to know enough to anticipate all driver performance errors, (b) the client's safety versus the client's right to independence, (c) financial constraints versus advantages of technology, and (d) the reporting of poor driving risk versus client confidentiality. A method for determining one's pattern of resolving ethical dilemmas is discussed.

Automobile Driving↗
PubMed1990

In vitro studies on the mechanism of action of hepsulfam in chronic myelogenous leukemia patients.

In the present study we have characterized the cytotoxicity and DNA damage induced by hepsulfam and busulfan in cells isolated from both chronic myelogenous leukemia (CML) patients and normal donors. hepsulfam inhibited colony-forming units-granulocyte, macrophage to a greater extent than busulfan in peripheral blood cells (PBCs) isolated from CML patients. Normal PBCs were equally sensitive to both agents and were more sensitive than the cells isolated from CML patients. Hepsulfam induced DNA interstrand cross-links in PBCs and bone marrow from both CML and normal volunteers, whereas busulfan produced few or no DNA interstrand cross-links. In addition, hepsulfam induced higher levels of DNA interstrand cross-linking than busulfam in three samples isolated from CML patients in blast crisis. Busulfan did however cause a small number of DNA strand breaks to be formed in human cells. Both agents produced similar levels of DNA-protein cross-links in PBCs from CML patients. These results suggest that the mechanism of DNA reactivity of hepsulfam and busulfan differ and that hepsulfam may prove useful in the treatment of CML.

Antineoplastic Agents↗
PubMed1990

In vivo suppression of erythropoiesis by tumor necrosis factor-alpha (TNF-alpha): reversal with exogenous erythropoietin (EPO).

Tumor necrosis factor-alpha (TNF-alpha) selectively kills tumor cells in vitro and in vivo and is being tested as a cancer therapeutic agent. We have shown that TNF-alpha significantly suppresses late-stage erythropoiesis, leading to anemia in chronically treated mice. These erythropoietic effects could limit the clinical use of TNF-alpha. Therefore, we have examined whether erythropoietin (EPO) could be used to prevent TNF-alpha-induced erythroid suppression. Normal mice were treated with a single dose of recombinant murine TNF-alpha (10(5) U/mouse, i.p.) with and without various concentrations of recombinant human EPO. After 3 days, effects on late-stage erythropoiesis were measured by determining the number of mature erythroid colony-forming cells (CFU-E) in the spleen and bone marrow. Simultaneous treatment with EPO abrogated the suppressive effect of TNF-alpha in a dose-dependent manner. EPO treatment also prevented the decrease in peripheral blood-hematocrit that was observed with chronic (5 x 10(4) U/mouse/day for 5 days) administration of TNF-alpha. TNF-alpha-induced hemorrhagic necrosis of tumors and stimulation of macrophage (CFU-M) progenitors were unaffected by EPO treatment. These results demonstrate that simultaneous injection of EPO can abrogate the TNF-alpha-induced suppressive effects on erythropoiesis.

Anemia↗
PubMed1989

Potentiation by adrenaline of thrombin-induced elevation of pHi is not essential for synergistic activation of human platelets.

Gel-filtrated human platelets were stimulated with thrombin in the absence and presence of adrenaline. Adrenaline markedly enhanced the thrombin-induced increase in cytoplasmic pH (pHi) in BCECF-loaded platelets. This rise in pHi was strongly inhibited by the Na+/H+ exchange blocker EIPA. The potentiation by adrenaline of thrombin-induced PLC activation measured as [32P]PA formation and final platelet responses was, however, not blocked by EIPA, even at low concentrations of thrombin. These results indicate that the enhancement by adrenaline of thrombin-induced cytoplasmic alkalinization may be a secondary effect which is not essential for the potentiation by adrenaline of platelet activation by thrombin.

Amiloride↗
PubMed1988

Use of actin-bound adenosine 5'-diphosphate as a method to determine the specific 32P-radioactivity of the gamma-phosphoryl group of adenosine 5'-triphosphate in a highly compartmentalized cell, the platelet.

Determination of the specific 32P-radioactivity of cytoplasmic ATP in 32P-Pi-labeled platelets is complicated by the presence of a large pool of metabolically inactive, granule-stored nucleotides. Moreover, our data show that the specific 32P-radioactivity of cytoplasmic ATP is severely underestimated when determined in platelets after the complete secretion of granule-stored nucleotides, possibly due to isotopic dilution with granule-stored phosphate. As F-actin-bound ADP is ethanol-insoluble, this pool can be readily separated from the other nucleotide pools in platelets. Here we show that the specific 32P-radioactivity of F-actin-bound ADP accurately reflects that of the gamma-phosphoryl group of cytoplasmic ATP. During uptake of 32P-Pi by human platelets the specific 32P-radioactivity of F-actin-bound ADP equals that of the monoester phosphates of phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate, which are in metabolic equilibrium with cytoplasmic ATP. Therefore, this method enables the determination of the specific 32P-radioactivity of the gamma-phosphoryl group of cytoplasmic ATP in platelets even under short-term labeling conditions.

Actins↗
PubMed1988

Pathophysiologic and pharmacotherapy considerations in the management of the black hypertensive patient.

The mortality and morbidity of hypertension-related diseases among blacks are much higher than in age- and sex-matched white counterparts. New data show that the incidence of renal damage may be 18 to 20 times greater in blacks than in whites. Some preliminary data also indicate that coronary heart disease is much more prevalent in blacks than previously suspected and that coronary heart disease mortality among blacks may indeed not be declining, as it is for white populations. Major contributors to these findings in blacks are an increased prevalence and severity of hypertension, a possibly increased susceptibility to end-organ damage, socioeconomic factors and beliefs that affect hypertension control, and very possibly some obsolete treatments that focus on blood pressure numbers and do not emphasize the black person and the associated risk factors. Diuretic therapy has long been the mainstay treatment for black hypertensives, but the effects of diuretics on lipid levels and left ventricular hypertrophy, among other factors, should be carefully assessed. A recent study of beta-blockers in blacks showed that metoprolol was effective and well tolerated. Consideration of epidemiologic, pathophysiologic, and pharmacotherapeutic features of hypertension in blacks may require traditional views of this disease and its treatment in this special population to be reevaluated.

Adrenergic beta-Antagonists↗
PubMed1988

Increasing patients' knowledge of radiation therapy.

Scripts for a set of patient education programs were developed by a multidisciplinary team of health care professionals to provide information to cancer patients receiving a 4-7 week course of external beam radiation therapy. The programs were designed to be presented sequentially at three critical points during a course of treatment: Pretreatment, Treatment Week 2, and Final Treatment Week. A total of 72 patients, 24 per program, with cancers of the lung, breast, or prostate, were assessed for their level of knowledge after hearing the audiotape appropriate to their treatment phase (posttest). Half of the patients, on a random basis, were also assessed prior to hearing their tape (pretest). This split design allowed the differentiation of true learning effects from effects of multiple assessments. Knowledge test items were developed from learning objectives for each program. Posttest results indicate a very high level of patient learning for all three programs, significantly exceeding the target of 75% correct. For patients tested twice, posttest scores were significantly higher than pretest scores. No testing effects were found for the Pretreatment and Treatment Week 2 programs. Final Treatment Week subjects who were pretested scored slightly higher on the posttest than their controls who were not pretested; however, additional analysis demonstrated true learning effects for this group as well. The results indicate that the programs are effective for increasing patients' knowledge regarding their treatment program, its side effects, and strategies to manage those side effects. Further research and intervention programs are discussed.

Audiovisual Aids↗
PubMed1987

Turnover of the phosphomonoester groups of polyphosphoinositol lipids in unstimulated human platelets.

The metabolic activity of the polyphosphoinositol lipids in unstimulated human platelets was studied by short-term labelling with [32P]Pi, by replacement of [32P]Pi from pre-labelled platelets with unlabelled phosphate, and by depriving the cells of metabolic ATP. Under short-term labelling conditions, the 4- and 5-phosphate groups of phosphatidylinositol 4-phosphate (PtdIns4P) and phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2] had the same specific 32P radioactivity as the gamma-phosphate of metabolic ATP. The specific 32P radioactivity of the 1-phosphates of phosphatidylinositol, PtdIns4P and PtdIns(4,5)P2 was similar, but only 4-13% compared to that of the ATP-gamma-phosphate. When [32P]Pi pre-labelled platelets were incubated with up to 25 mM of unlabelled phosphate, the displacement of the 32P label from PtdIns4P, PtdIns(4,5)P2 and metabolic ATP followed similar kinetics. Inhibition of ATP regeneration in platelets pre-labelled with [32P]Pi resulted in a rapid fall in metabolic ATP with a much slower fall in [32P]PtdIns(4,5)P2, whereas [32P]PtdIns4P increased initially. However, ATP turnover was not abolished, as indicated by the marked (25% of the control) incorporation of extracellular [32P]Pi into PtdIns4P and PtdIns(4,5)P2 in metabolically inhibited platelets. This low phosphate turnover may explain the relative resistance of PtdIns4P and PtdIns(4,5)P2 to metabolic inhibition. We conclude that PtdIns4P and PtdIns(4,5)P2 are present as a single metabolic pool in human platelets. Turnover of the 4- and 5-phosphates of PtdIns4P and PtdIns(4,5)P2 in unstimulated platelets is as rapid as that of the gamma-phosphate of metabolic ATP, and accounts for about 7% of basal ATP consumption.

Adenosine Diphosphate↗
PubMed1987

Stimulation of phosphate uptake in human platelets by thrombin and collagen. Changes in specific 32P labeling of metabolic ATP and polyphosphoinositides.

The uptake of [32P]phosphate by human, gel-filtered blood platelets and its incorporation into cytoplasmic ATP and polyphosphoinositides was studied. In unstimulated platelets, uptake was Na+o-dependent and saturable at approximately 20 nmol/min/10(11) cells with a half-maximal rate at 0.5 mM extracellular phosphate. Upon stimulation with thrombin or collagen, net influx of [32P]Pi was accelerated 5- to 10-fold. With thrombin, [32P]Pi efflux was also increased. After the first 2 min, efflux exceeded influx, resulting in the net release of [32P]Pi from the platelets. Since the stimulus-induced burst in [32P]Pi uptake paralleled the secretory responses, it might be an integral part of stimulus-response coupling in platelets. The stimulus-induced burst in net [32P]Pi uptake led to an enhanced labeling of metabolic ATP, which was already detectable at 5 s after stimulation with thrombin. Concomitantly, the incorporation of [32P]Pi into phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate was accelerated. The thrombin-induced increase in specific 32P radioactivity of cytoplasmic ATP fully accounted for the simultaneous increase in specific 32P radioactivity of these phosphoinositides. In studying the extent of 32P labeling of phosphorylated compounds in response to a cellular stimulus, it is therefore essential to measure the effect of the stimulus on the specific radioactivity of cytoplasmic ATP.

Adenosine Triphosphate↗