Search PubMed⌕ Search

Biomedical subjects

K Robinson

Publications and source records attributed to K Robinson.

At least 19 recordsLinked to original sources
PubMed1992

The 15-year prognosis of a first acute coronary episode in women.

We report on the 15-year prognosis of 720 male and 246 female 28-day survivors of a first myocardial infarction or episode of unstable angina who were aged under 60 years at the time of admission to the study. Women were on average 1.9 years older than men, had higher cholesterol levels, a higher prevalence of hypertension and angina prior to admission and a higher proportion were lifetime non-smokers. Women were more likely to be admitted with unstable angina rather than infarction. When adjusted for age, smoking status, angina, hypertension and the difference in prevalence of infarction, women had a relative risk of death of 1.054 in a 15-year life table mortality analysis. Prognostic differences between the sexes reported may be the result of failure to allow for differences in other prognostic factors.

Adult↗
PubMed1992

Molecular typing of candida albicans isolated from oral lesions of HIV-infected individuals.

OBJECTIVE: To evaluate the epidemiology of Candida albicans infection in HIV-infected patients with oral lesions using molecular techniques. METHODS: Thirty-nine isolates from HIV-positive patients with oral candidiasis were examined using two DNA probes (a Histoplasma capsulatum ribosomal DNA probe that cross-hybridizes with C. albicans and a C. albicans strain-specific probe derived from repetitive sequence DNA). C. albicans obtained from the oral cavity of patients receiving cytotoxic chemotherapy was used as controls. RESULTS: Using the H. capsulatum ribosomal DNA probe, isolates were shown to members of many distinct classes of C. albicans. Forty-nine per cent (19 out of 39) of isolates were members of the same class; however, 46% (6 out of 13) of control C. albicans isolates were also members of this class. Further analysis of the class-restricted isolates from the HIV-infected patients using the C. albicans strain-specific probe showed that these could be further separated into distinct strains. CONCLUSIONS: These data indicate that strains of C. albicans that cause oral candidiasis in HIV-positive individuals are not clonally restricted and are similar to those colonizing the oral cavity of other severely immunocompromised hosts. Most patients appear to be infected with unique strains of C. albicans.

Blotting, Southern↗
PubMed1992

Primary pulmonary hypertension and functional hyposplenism.

Primary pulmonary hypertension is a rare disease of unknown case. Functional hyposplenism is characterized by the appearance of abnormal circulating erythrocytes despite the presence of a spleen and is associated with a variety of disease states. A case of primary pulmonary hypertension associated with functional hyposplenism is described in this report.

Adult↗
PubMed1992

Gaps and contract: evaluating the diffusion of new information. Part I. A description of the strategy.

Time and fiscal constraints on oncology nurses require that continuing education programs yield demonstrable benefit to the clinician, the institution, and patient outcomes. This article describes "gaps and contract," a strategy that provides nurses with a tool to transfer knowledge from theory to practice, in a measurable form. The framework for this strategy lies within the concept of innovation diffusion. This strategy was used by two universities collaborating to educate 912 oncology health professionals in 38 continuing education programs. Part II of this article will describe the measurement of this strategy.

Child↗
PubMed1992

Gaps and contract: evaluating the diffusion of new information. Part II. The measurement of the strategy.

This article is the second of a two-part series describing "gaps and contract," a strategy that provides nurses with a mechanism to transfer knowledge from theory into practice in a measurable format. Two universities under contract from the Pennsylvania state cancer plan used this strategy to evaluate the effectiveness of a cancer continuing education program. Two hundred seventy-four (274) contracts from one setting and 205 from a second setting are described. Recommendations for using this strategy to measure the efficacy of cancer continuing education programs are included.

Adult↗
PubMed1991

The time interval between death and next-of-kin contact and its effects on response rates and data quality.

The relation of the interval of time between death and next-of-kin contact to outcome variables including response rates and data quality was examined in a nationally representative sample of 17,713 deaths of persons 25 years of age or older that occurred in the United States in 1986. For most of the outcome variables examined, the length of time had little effect, although there was a small decrease in the response rate and a small increase in the refusal rate for contact 40 or more weeks after death. The small decrease in the response rate and small increase in the refusal rate for the longest interval examined held for most decedent background characteristics examined (age, race, cause of death, and type of informant.) Authorizations to contact health care facilities signed by the respondents decreased slightly as the interval increased. The rate of returned mailed questionnaires passing quality and consistency edits increased slightly with time since death. Substantive responses (versus blanks, don't knows, etc.) decreased as time since death increased. Certain questions such as those on income and birth control pill use showed a decrease in response with time since death. Overall, the effects of longer time intervals between death and next-of-kin contact were less than expected on response rates and data quality, although our findings may reflect the high overall response rate, 90.5%, leaving little opportunity for significant areas of nonresponse.

Adult↗
PubMed1991

Hyperhomocysteinemia: an independent risk factor for vascular disease.

BACKGROUND: Hyperhomocysteinemia arising from impaired methionine metabolism, probably usually due to a deficiency of cystathionine beta-synthase, is associated with premature cerebral, peripheral, and possibly coronary vascular disease. Both the strength of this association and its independence of other risk factors for cardiovascular disease are uncertain. We studied the extent to which the association could be explained by heterozygous cystathionine beta-synthase deficiency. METHODS: We first established a diagnostic criterion for hyperhomocysteinemia by comparing peak serum levels of homocysteine after a standard methionine-loading test in 25 obligate heterozygotes with respect to cystathionine beta-synthase deficiency (whose children were known to be homozygous for homocystinuria due to this enzyme defect) with the levels in 27 unrelated age- and sex-matched normal subjects. A level of 24.0 mumol per liter or more was 92 percent sensitive and 100 percent specific in distinguishing the two groups. The peak serum homocysteine levels in these normal subjects were then compared with those in 123 patients whose vascular disease had been diagnosed before they were 55 years of age. RESULTS: Hyperhomocysteinemia was detected in 16 of 38 patients with cerebrovascular disease (42 percent), 7 of 25 with peripheral vascular disease (28 percent), and 18 of 60 with coronary vascular disease (30 percent), but in none of the 27 normal subjects. After adjustment for the effects of conventional risk factors, the lower 95 percent confidence limit for the odds ratio for vascular disease among the patients with hyperhomocysteinemia, as compared with the normal subjects, was 3.2. The geometric-mean peak serum homocysteine level was 1.33 times higher in the patients with vascular disease than in the normal subjects (P = 0.002). The presence of cystathionine beta-synthase deficiency was confirmed in 18 of 23 patients with vascular disease who had hyperhomocysteinemia. CONCLUSIONS: Hyperhomocysteinemia is an independent risk factor for vascular disease, including coronary disease, and in most instances is probably due to cystathionine beta-synthase deficiency.

Cerebrovascular Disorders↗
PubMed1991

Hypercholesterolaemia: simvastatin and pravastatin alter cholesterol metabolism by different mechanisms.

The 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor simvastatin, reduced low-density-lipoprotein (LDL) cholesterol in hypercholesterolaemic patients by 40% (P less than 0.001). The reduction in LDL cholesterol was accompanied by a significant decrease in the esterified/free cholesterol ratio of the patients' LDL from 2.51 +/- 0.13 to 2.06 +/- 0.14 (P less than 0.01). This change led to a significant increase (P less than 0.05) in the capacity of the LDL to suppress [14C]acetate incorporation into cholesterol in mononuclear leucocytes. Furthermore, [14C]acetate incorporation into the patients mononuclear leucocytes was significantly lower (P less than 0.02) following drug treatment (117 +/- 22 vs. 162 +/- 29 nmol/mg cell protein). Comparison of simvastatin with another HMG-CoA reductase inhibitor pravastatin, showed similar reduction in LDL cholesterol. Pravastatin treatment however, did not result in a reduction in the LDL esterified/free cholesterol ratio or in the changes in cellular cholesterol synthesis and its regulation by LDL which accompanied simvastatin treatment. The activity of the enzyme acyl-coenzyme A: cholesterol acyltransferase (ACAT) in patients' mononuclear cells remained unchanged after treatment with either drug. Results of the study show that while the drugs are equally effective in lowering LDL cholesterol, simvastatin has additional compositional effects on LDL which increase its capacity to regulate mononuclear leucocyte cholesterologenesis.

Adult↗
PubMed1991

The coronary artery response to implantation of a balloon-expandable flexible stent in the aspirin- and non-aspirin-treated swine model.

Intracoronary stents may potentially alleviate some of the problems associated with coronary angioplasty. Since the anatomy and physiology of swine coronary arteries closely resemble those of humans, the response to implantation of the Glanturco-Roubin, balloon-expandable, flexible stent was studied in this model. Additionally, the effect of aspirin, 1 mg/kg/day orally, on this response was evaluated. Eighteen Hanford minature swine underwent stenting of the left anterior descending coronary artery. Two died within 24 hours of stent implantation. The 16 survivors were put to death at 4 (n = 4), 11 (n = 4), 28 (n = 4), 56 (n = 3), and 180 (n = 1) days. Angiographically, reduction of stent lumen diameter of 0.1 to 1.3 mm was observed and was maximum at 11 days, with gradual improvement at subsequent time periods. Scanning electron microscopy, transmission electron microscopy, and light microscopy showed early disruption of subjacent endothelium, and adherence of platelets to exposed subendothelium and stent wires. Microthrombi were readily apparent. At 11 days, intimal thickening, made up predominantly of smooth muscle cells with abundant extracellular matrix, was observed and covered the stent wires. At 28 days, regression of intimal thickening was apparent and a confluent endothelium with flow-directed orientation was seen. At 56 and 180 days, the luminal surface was smooth; intimal thickening averaged 525 microns over the stent wires and 55 microns away from the wires. Findings in aspirin-treated animals were similar to results in those that did not receive aspirin. Thus in this swine model, stent implantation results in a time-dependent and self-limited vascular response.

Angioplasty, Balloon, Coronary↗
PubMed1991

rab3A attachment to the synaptic vesicle membrane mediated by a conserved polyisoprenylated carboxy-terminal sequence.

rab3A is a small neuronal GTP-binding protein specifically localized to synaptic vesicles. Membrane-bound rab3A behaves like an intrinsic membrane protein in vitro, but reversibly dissociates from synaptic vesicles after exocytosis in vivo. Here we demonstrate that rab3A is attached to synaptic vesicle membranes by a carboxy-terminal Cys-X-Cys sequence that is posttranslationally modified. This modification is inhibited by compactin in a mevalonate-dependent manner, suggesting that the Cys-X-Cys sequence represents a novel polyisoprenylation sequence. Isolation of a rab3 homolog from D. melanogaster reveals high evolutionary conservation of rab3A, including its carboxy-terminal Cys-X-Cys sequence. The posttranslational modifications of soluble and membrane-bound rab3A are biochemically different, but both require the carboxy-terminal Cys-X-Cys sequence and are faithfully reproduced in nonneuronal cells. Our results suggest that the carboxy-terminal Cys-X-Cys sequence of rab3A is polyisoprenylated and is used as its regulatable membrane anchor. Furthermore, the hydrophobic modification of rab3A and its correct intracellular targeting to synaptic vesicles are independent, presumably consecutive events.

Amino Acid Sequence↗
PubMed1991

A prospective study in the Australian petroleum industry. I. Mortality.

This paper reports the mortality experience of employees of the Australian petroleum industry from 1981 to 1989. Two surveys by personal interview incorporated more than 15,000 employees representing 92% of the eligible population. Subjects were included in the analysis after completing five years of service in the industry. At the time of this report the cohort does not include sufficiently large numbers of women for useful analysis; results presented are restricted to men. By 31 December 1989, 76,529 person-years of observation had accumulated for male mortality with 241 deaths. The standardised mortality ratio (SMR) analysis showed a favourable mortality experience for most causes with overall cancer rates slightly lower than those of the national population. Whereas deficits were seen in some cancer sites, notably lung cancers (SMR 0.5, 95% confidence interval (95% CI) 0.3-0.8), mortality for lymphohaematopoietic cancers, notably leukaemia (SMR 1.6, 95% CI 0.6-3.4) suggested increased risk. The SMR for cancers of the pleura was 3.9 (95% CI 0.8-11). Two of the three cases seen had previous employment, however, in industries with likely exposure to asbestos.

Australia↗
PubMed1991

A prospective study in the Australian petroleum industry. II. Incidence of cancer.

This paper reports incidence of cancer in employees of the Australian petroleum industry from 1981 to 1989. Two surveys by personal interview incorporated more than 15,000 employees, representing 92% of the eligible population. Subjects were included in the analysis after completing five years of service in the industry. At the time of this report the cohort did not include sufficiently large numbers of women for useful analysis; results presented are restricted to the men. On 31 December 1989, 50,254 person-years of observation had accumulated in the men with 152 incident cancers reported. The standardised incidence ratio (SIR) analysis showed overall cancer rates close to those of the national population. Whereas deficits were seen in some cancer sites, notably lung cancer (SIR 0.5, 95% confidence internal (95% CI) 0.3-0.9), incidence rates for some other cancer sites suggested increased risk. An excess of observed over expected cases was present in all subcategories of lymphohaematopoietic cancer except Hodgkin's disease (no cases), and was most apparent in myeloid leukaemia (SIR 4.0, 95% CI 1.6-8.2). The other major site with a raised number of cases observed over expected was melanoma (SIR 1.4, 95% CI 0.8-2.1).

Australia↗
PubMed1991

Hyperhomocysteinaemia and multiple aneurysms.

Homozygous homocystinuria, the most common genetic disorder of transulphuration, is associated with elevated plasma concentrations of homocystine, homocysteine, multiple clinical abnormalities and life-threatening thromboembolism. Several instances of vascular aneurysms have also been documented. More recently, an association between premature occlusive vascular disease and the heterozygous state has been proposed. We now report an unusual case in whom multiple aneurysms were associated with heterozygous homocystinuria.

Amino Acid Metabolism, Inborn Errors↗
PubMed1991

In-hospital prognosis of patients with fasting hyperglycemia after first myocardial infarction.

OBJECTIVE: To investigate the incidence and prognostic significance of fasting hyperglycemia in a large group of patients with a first myocardial infarction. RESEARCH DESIGN AND METHODS: Blood glucose was measured after an 8-h overnight fast in 752 patients with a first myocardial infarction. Three groups of patients were identified: patients with normal fasting blood glucose (92.5%), patients with fasting hyperglycemia but no prior history of glucose intolerance (3%), and patients previously known to have diabetes mellitus (4.5%). RESULTS: The fasting hyperglycemic patients were significantly older and had significantly more in-hospital complications than the normal blood glucose group. Previously known diabetic subjects tended to be older and had more mechanical complications postinfarction than the group with normal blood glucose but the difference did not reach statistical significance. There was no significant difference between the diabetic subjects and patients with fasting hyperglycemia in mean age and in-hospital prognosis. CONCLUSIONS: Fasting hyperglycemia detected after a first myocardial infarction is associated with a poor in-hospital prognosis that was not due to larger infarct size, as reflected in peak levels of cardiac enzymes. The measurement of a fasting blood glucose level provides additional information in identifying high-risk groups of patients postinfarction.

Blood Glucose↗