PubMed Health⌕ Search

Biomedical subjects

D Sweeney

Publications and source records attributed to D Sweeney.

At least 37 records · Page 2Linked to original sources
PubMed1996

The Big-Five factor structure as an integrative framework: an analysis of Clarke's AVA model.

Using a large (N = 3,629) sample of participants selected to be representative of U.S. working adults in the year 2,000, we provide links between the constructs in 2 personality models that have been derived from quite different rationales. We demonstrate the use of a novel procedure for providing orthogonal Big-Five factor scores and use those scores to analyze the scales of the Activity Vector Analysis (AVA). We discuss the implications of our many findings both for the science of personality assessment and for future research using the AVA model.

Adolescent↗
PubMed1996

Fibronectin in the tear film.

PURPOSE: Fibronectin plays an important role in corneal healing and has been detected previously in the tear film. To investigate the levels of fibronectin in normal human tears, the authors measured and compared fibronectin concentration in open-eye, closed-eye, and reflex tear fluid. The origin of fibronectin in the tear film was investigated by comparing fibronectin concentration in sequentially collected reflex tear samples with the concentrations of total protein and albumin in the same samples. METHODS: Open-eye and closed-eye tears were collected from 11 noncontact lens wearers. From 7 subjects, 20 uninterrupted reflex tear samples (10 microliters each) subsequently were collected, using the sneeze reflex method of stimulation, followed by an additional 10 nonstimulated tear samples (3 microliters each) immediately after cessation of stimulus. Enzyme-linked immunosorbent assays were used to determine fibronectin and albumin concentrations, and bicinchoninic acid protein assays were used to determine total protein concentration in each sample. RESULTS: Fibronectin concentration in open-eye tears (19 +/- 24 eta g/ml, range 3 to 78 eta g/ml) was significantly different (P = 0.004) from that in closed-eyes tears (4127 +/- 3222 eta g/ml, range 1177 to 11384 eta g/ml). In the first 50 microliters of reflex tears, fibronectin concentrations were low (10 +/- 23 eta g/ml), but they increased significantly (P = 0.028) after 100 microliters of reflex tears had been collected (220 +/- 126 eta g/ml). There was a further marked transient increase (767 +/- 946 eta g/ml) after cessation of stimulus. Total protein concentration in the same samples decreased significantly during reflex tear collection compared to open-eye tears, and it increased gradually after cessation of stimulus. Albumin concentration in the same samples, analyzed for two subjects only, showed a pattern similar to that for fibronectin. Dilation of conjunctival blood vessels was noted in all subjects after reflex tear collection. Administration of a topical vasoconstrictor in two subjects eliminated the increase in fibronectin concentration during reflex tearing but did not affect total protein concentration. Under reducing conditions, the molecular mass of fibronectin in open-eye and reflex tears was 240 kDa, identical to commercially available purified plasma fibronectin, whereas fibronectin in closed-eye tears was degraded into small molecular mass fragments. CONCLUSIONS: These findings suggest that fibronectin in tear fluid is derived from plasma and that the increase in concentration in closed-eye and reflex tear fluid is caused by leakage from dilated conjunctival blood vessels.

Adult↗
PubMed1995

High levels of amyloid-beta protein from S182 (Glu246) familial Alzheimer's cells.

Most early-onset familial Alzheimer disease is associated with missense mutations in S182, a membrane protein on chromosome 14. We investigated amyloid-beta protein (A beta) precursor (A beta PP) metabolism in skin fibroblasts from S182 (Glu246)-affected individuals and unaffected family members. Steady-state A beta PP levels were similar among all lines as was the degree of increase in soluble A beta PP released upon stimulation of cells with either phorbol ester or serum. Among all lines studied, A beta levels were consistently detectable only in the medium of a single line of S182 (Glu246) cells, consistent with the conclusion that some S182 mutant lines may accumulate A beta in their conditioned media. Studies of cells from additional individuals and under other conditions will be required to establish this association of elevated A beta levels with S182 mutations.

Age of Onset↗
PubMed1993

CCLRU standards for success of daily and extended wear contact lenses.

Success in contact lens wear is often judged on the basis of patient "survival" rather than the achievement of satisfactory performance based on specific criteria. In 1971, Sarver and Harris defined a series of standards for successful polymethyl methacrylate (PMMA) lens wear which incorporated criteria for wearing time, comfort, vision, ocular tissue changes, and patient appearance. In this paper we propose a revision of these criteria based on current understanding of the ocular response to contact lens wear. These revised CCLRU (Cornea and Contact Lens Research Unit) standards for success are intended as realistic performance objectives, and can be applied in clinical trials to evaluate and compare the clinical performance of present and future rigid and soft contact lenses, worn for daily and extended wear.

Contact Lenses↗
PubMed1991

Sodium dodecyl sulphate-polyacrylamide gel electrophoresis of human parotid salivary proteins.

The proteins in human parotid saliva have been separated by sodium dodecyl sulphate-polyacrylamide gel electrophoresis into 20 or more well resolved species. The Coomassie Brilliant Blue (CBB) R-250 and silver staining procedures have been modified to overcome the problems encountered with staining of proline-rich proteins. By means of the CBB R-250 procedure which stains proline-rich proteins pink-violet, immunoblotting, concanavalin A binding, periodate-Schiff staining and zinc binding, all of the major proteins have been characterised. Substantial individual-to-individual differences were observed in the protein patterns formed. Comparison of parotid, submandibular, and whole saliva from a single individual indicated that fewer proline-rich proteins are expressed in submandibular saliva than in parotid, but whole saliva contains much lower levels than either duct secretion. The results will form a useful base for future research into the functions of salivary proteins.

Electrophoresis, Polyacrylamide Gel↗
PubMed1991

Salivary secretion of albumin in type 1 (insulin-dependent) diabetes.

The concentration of albumin in saliva is low in healthy humans. To determine whether alterations in capillary permeability in diabetes affects the salivary glands, the concentration of albumin in parotid saliva was measured in 26 Type 1 (insulin-dependent) diabetic patients, and compared to 32 non-diabetic control subjects. The diabetic patients were subdivided into 3 groups on the basis of the urinary excretion of albumin in timed overnight collections of urine: (1) normal albumin excretion (less than 30 micrograms/min) n = 13; (2) microalbuminuria (30-300 micrograms/min) n = 7, and (3) macroalbuminuria (greater than 300 micrograms/min) n = 6. Saliva was collected for one minute following stimulation with 1 ml 10% citric acid, and the concentration of albumin was measured by a sensitive ELISA method. No significant difference in salivary albumin concentration was found between the control group and any of the diabetic groups. Thus, although urinary albumin excretion was increased, suggesting altered capillary permeability, simultaneous leakage of albumin into saliva was not observed. Measurement of salivary albumin concentration does not, therefore, provide a marker of occult microvascular disease in diabetes.

Adult↗
PubMed1990

Microbial infection and the septic response in critical surgical illness. Sepsis, not infection, determines outcome.

The differential roles of infection as a microbial phenomenon and sepsis as a host response were studied in 210 critically ill surgical patients. Infections occurred in 41.4% of all cases and in 82% of nonsurviving patients. Both infection and the expression of a septic response, measured as a sepsis score, were associated with significantly increased intensive care unit morbidity and mortality. Nonsurviving patients with infection had significantly higher sepsis scores than did survivors. Nonsurvivors with sepsis, on the other hand, did not differ from survivors with respect to any variable reflecting infection but did have higher mean sepsis scores. Maximum sepsis scores and sepsis scores on the day of death were similar in patients dying without infection and those dying with uncontrolled infection. The magnitude of the host septic response, independent of the presence, bacteriologic characteristics, or control of infection, is an important determinant of outcome in critical surgical illness.

Bacterial Infections↗
PubMed1990

An enzyme-linked immunoassay for human salivary albumin.

An ELISA method has been developed for the determination of albumin in human parotid saliva. The range of sensitivity is 2-80 micrograms/l and it is suitable for use with volumes of 5 microliters or less of freshly collected parotid fluid, without prior sample preparation. Calibration data were fitted by microcomputer to an exponential function. The albumin concentration of parotid saliva was 1.9 +/- 1.53 mg/l, but levels fell on sample storage. Isoelectric focusing, followed by immunoblotting with antiserum to human serum albumin, showed identical double bands of pI 4.9-5.0 in albumin from both serum and saliva, thereby confirming that the antigens from the two sources are identical.

Adolescent↗
PubMed1989

Quantitative analysis of polyols in human plasma and cerebrospinal fluid.

We used gas chromatography in conjunction with flame ionization detection to quantitate nine polyols and aldo and keto sugars (as silyl derivatives) in human plasma and cerebrospinal fluid (CSF). Rhamnose, not found in CSF or plasma, was used as an internal standard with a lower limit of quantitation of 0.4 mg/l. CSF polyol and sugar concentrations (mean +/- S.D.) in fourteen healthy subjects (age range 27.1-85.9 years) were: anhydroglucitol, 19.9 +/- 5.3 mg/l; arabitol, 4.8 +/- 0.9 mg/l; erythritol, 2.4 +/- 0.5 mg/l; myoinositol, 28.6 +/- 8.3 mg/l; ribitol, 1.6 +/- 0.1 mg/l; fructose, 25.5 +/- 11.1 mg/l; glucose, 587 +/- 70 mg/l; glucitol, 7.7 +/- 1.5 mg/l; and mannose, 10.6 +/- 2.4 mg/l. The respective plasma concentrations were 30.6 +/- 11.5, less than 0.4, 0.4 +/- 0.2, 6.3 +/- 2.6, less than 0.4, 23.4 +/- 21.4, 897 +/- 214, less than 0.4 and 13.7 +/- 6.3 mg/l. Polyol CSF-to-plasma concentration ratios greater than 2 were observed for myoinositol, erythritol, arabitol, glucitol and ribitol, indicative of active accumulation or synthesis of these polyols within the central nervous system.

Adult↗
PubMed1989

The effect of RG 12525 on leukotriene D4-mediated pulmonary responses in guinea pigs.

RG 12525 (5-(2-[4-quinolin-2-yl)methoxyl] phenoxymethyl)benzyl tetrazole) is under investigation as a specific inhibitor of leukotriene D4 (LTD4). The present studies examine the effect of orally administered RG 12525 on LTD4 mediated pulmonary responses in three separate guinea pig models. The compound inhibited antigen-induced mortality in the systemic anaphylaxis model with an ED50 (95% confidence interval) = 2.2 (0.8-6.4) mg/kg. In this model, the activity half-life of RG 12525 was shown to be 6.5 hours and the compound offered significant protection within 15 minutes of administration. RG 12525 also protected against LTD4-induced bronchoconstriction in a model measuring changes in pulmonary function with an ED50 = 0.6 (0.4-1.0) mg/kg. The same level of activity was observed in a similar model which monitored changes in pulmonary function in response to exogenous antigen in actively-sensitized guinea pigs. Together, these data indicate that RG 12525 is a potent, orally active LTD4 antagonist which possesses the requisite profile for potential clinical development.

Anaphylaxis↗
PubMed1989

Coping strategies and diastolic blood pressure.

An organizational field study involving 95 civil service employees examined the ways these individuals coped with the stressful events of their daily living. Lazarus' cognitive-phenomenological analysis of psychological stress provided the theoretical framework. Subjects indicated on Lazarus' Ways of Coping Checklist those coping thoughts and actions used in the specific encounter described as stressful. As hypothesized, individuals experiencing higher diastolic blood pressure were more likely to cope using strategies characterized by wishful thinking, avoidance, and minimization of threat than were individuals exhibiting lower blood pressure. Implications from both an individual and organizational perspective are discussed.

Adaptation, Psychological↗
PubMed1988

Co-oxidation of arachidonic acid and methimazole by prostaglandin endoperoxide synthetase.

The thiocarbamide methimazole stimulated O2 utilisation when added to reaction mixtures containing ram seminal vesicle microsomes (prostaglandin endoperoxide synthetase preparation) and arachidonic acid. This stimulation increased with increasing methimazole concentrations, as did the production of prostaglandin E. 2-[14C]Methimazole was co-oxidized to 1-methyl-2-[14C]imidazole.

Animals↗
PubMed1988

Neuropsychiatric assessment of a spinal cord injury patient with sudden recovery.

Reported here is the case of a 23-year-old man who, presenting as a spinal cord injury patient with paraplegic and bilateral sensory impairments in the legs, made a rather dramatic recovery after receiving a trivial jolt while moving about in his wheelchair. In addition to clinical findings, both hypnotic and somatosensory evoked potential test results were used to help determine whether there was or was not actual spinal cord injury and whether there was or was not a psychologic overlay involving either malingering or a conversion disorder. In this case, evidence pointed to malingering in the presence of a minor spinal cord injury documented by somatosensory evoked potential patterns.

Adult↗
PubMed1987

The effect of halothane general anaesthesia on platelet function.

Major craniofacial surgery has the potential for very large blood loss, frequently greater than one blood volume. In order that an assessment could be made of any deficiencies of platelet function or coagulation, tests were performed at intervals during the operation. None of the coagulation parameters showed variation below normal limits during the operation, but in vitro platelet aggregation showed significant decreases to several agonists.

Adolescent↗
PubMed1987

Eating disorders and cocaine abuse: a survey of 259 cocaine abusers.

A structured clinical interview designed to diagnose eating disorders was administered to 259 consecutive callers to the National Cocaine Hotline who met DSM-III criteria for cocaine abuse. Thirty-two percent of those surveyed met DSM-III criteria for either anorexia nervosa, bulimia, or both disorders. The prevalence rates for each of these disorders in this sample appeared elevated even when narrow diagnostic criteria were applied. The data suggest that drug abusers should be screened carefully for the presence of an eating disorder and that abnormalities of eating behaviors seen among these individuals should not be attributed simply to drug use.

Adolescent↗
PubMed1985

Brain palmitate incorporation in awake and anesthetized rats.

Uniformly labeled [14C]palmitate was injected intravenously in awake and barbiturate-anesthetized rats, and arterial plasma radioactivity due to unesterified [14C]palmitate was determined on plasma samples removed at timed intervals up to the time of death. Overall brain radioactivity was determined by liquid scintillation spectroscopy, and regional brain radioactivity was determined by quantitative autoradiography. The transfer constant, k, for the unidirectional uptake of radiotracer palmitate into the brain at 4 h was calculated from the brain radioactivity and the integrated plasma radioactivity from injection to 4 h. The unidirectional palmitate uptake was calculated as the product of k and the plasma concentration of unesterified palmitate. Barbiturate anesthesia reduced regional palmitate transfer constants and unidirectional palmitate uptakes into different brain regions by 40-60%. Palmitate incorporation into the brains of awake rats at 4 h represents uptake into structural brain components which contain lipids. The results indicate that pentobarbital anesthesia reduces this rate of incorporation by about half.

Anesthesia↗
PubMed1985

Repair of long-term venous catheters.

The insertion of long-term Silastic catheters into the vena cava for home parenteral nutrition, antibiotic administration, and chemotherapy is increasing; however, one of the often described complications of these catheters is breakage of the external segment of the catheter. A new device as well as a new method for repair of the catheter has been described. Clinical testing of the catheters repaired with this device by our nutritional support service has demonstrated no leakage or occlusion at the catheter repair site. We believe the catheter repair kit described is simpler to use than the repair kit currently on the market.

Catheters, Indwelling↗