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K W Davidson

Publications and source records attributed to K W Davidson.

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

Plasma concentrations of dihydro-vitamin K1 following dietary intake of a hydrogenated vitamin K1-rich vegetable oil.

Dihydro-vitamin K1 is a dietary form of vitamin K1 (phylloquinone) produced during the hydrogenation of vegetable oils. To determine if dihydro-vitamin K1 is present in plasma following dietary intake of a hydrogenated fat, eight healthy adults consumed each of two diets containing 30% of calories from fat, of which 20% was either soybean oil or a partially hydrogenated soybean oil-based stick margarine. Of the fats and oils analyzed, dihydro-vitamin K1 was only found in the hydrogenated products. The soybean oil diet contained 180 +/- 12 micrograms (mean +/- SD) of vitamin K1/day and nondetectable levels of dihydro-vitamin K1, whereas the stick margarine diet contained 199 +/- 7 micrograms of vitamin K1/day and 23 +/- 2 micrograms of dihydro-vitamin K1/day. After consuming each diet for five weeks, plasma dihydro-vitamin K1 concentrations were higher (P = 0.002) in all eight subjects when consuming the stick margarine diet (0.56 +/- 0.33 nmol/L) compared to the soybean oil diet (0.12 +/- 0.11 nmol/L). There was no significant change in plasma vitamin K1 concentrations when the two diets were compared. In conclusion, dihydro-vitamin K1 is detectable in plasma following dietary intake of a hydrogenated vitamin K1-rich vegetable oil.

Aged↗
PubMed1996

Increases in depression after cholesterol-lowering drug treatment.

To investigate the possibility that increases in depressive symptoms might occur in patients who have undergone cholesterol-lowering interventions, the authors administered the Center for Epidemiological Studies-Depression scale before and after cholesterol lowering to 6 men who were referred to a lipid clinic. All of the patients' cholesterol levels were reduced after the 6-week intervention, and 4 of the patients' depression scores increased; scores of 2 of the 4 met the criteria for mild clinical depression. Further study of possible links among low cholesterol, depressive symptoms, and serotonergic activity is needed.

Anticholesteremic Agents↗
PubMed1996

Is there an association among low untreated serum lipid levels, anger, and hazardous driving?

Anger and hazardous driving were explored in two studies for their possible explanatory role in the low cholesterol-violent mortality association. In Study 1, we obtained fasting blood samples and indices of anger and driving habits from 102 healthy young adults. Among men (but not women), lower low-density lipoprotein (LDL) cholesterol levels were associated with significantly higher anger (r = 41, p < .01) and unsafe driving habits (r = -.30, p < .05), and although total cholesterol levels were correlated in the predicted direction, these were not significant. In Study 2, 78 healthy young men completed the same measures, and this time, both lower total and LDL-cholesterol were significantly related to increased anger and dangerous driving. Implications of these findings are discussed as are possible avenues for future research. Further scrutiny of the components of serum cholesterol and their relation to psychological factors may aid us in better understanding the reasons why men are at increased risk for hazardous behavior and violent death.

Journal Article↗
PubMed1995

Social work with dying and bereaved clients: helping the workers.

This paper considers the stresses and satisfactions experienced by health care social workers as they help clients with grief and loss at a time of great fiscal restraint. Their clients face life-threatening illnesses such as AIDS and many forms of cancer. There are untimely losses in families and communities whose resources are dwindling. As social workers confront struggles with death and bereavement, they may receive limited support to deal with these stresses in their work. The authors suggest administrative strategies both to help workers reduce stress and increase satisfactions and to demonstrate the value of social work services to dying and bereaved clients along a continuum of health care.

Acquired Immunodeficiency Syndrome↗
PubMed1995

The pharmacokinetics and lipoprotein fraction distribution of intramuscular vs. oral vitamin K1 supplementation in women of childbearing age: effects on hemostasis.

Prenatal maternal vitamin K1 supplementation to improve the hemostatic status of the fetus may depend upon the route of administration and subsequent presentation at the placental barrier. We investigated intramuscular (IM) vs oral (PO) vitamin K1 supplementation in eight healthy, nonpregnant women of childbearing age. Pharmacokinetics were studied in each subject after a 5 mg IM dose and after a 5 mg oral dose of vitamin K1 approximately one month later. Plasma collected at the peak vitamin K level for each treatment was separated into very low density lipoproteins (VLDL), low density lipoprotein (LDL), high density lipoprotein (HDL) and lipoprotein-free fractions by density gradient ultracentrifugation. Vitamin K1 was measured in the plasma and lipoprotein fractions using HPLC. The concentration of vitamin K1 in plasma reached a peak 2 h after an IM dose and remained high throughout the 30 h course of the study. In contrast, the oral dose of vitamin K1 peaked at 4 h and rapidly decreased to near baseline by 18 to 30 h. The distribution of vitamin K1 in the lipid fractions was different for IM compared to PO. The percentage of vitamin K1 in the VLDL fraction at the peak for an oral dose was significantly higher than for an IM dose (80.8% +/- 3.5 vs 10.8% +/- 6.5, p < 0.0001). After the oral absorption stage, the subjects took 5 mg of vitamin K1 orally, once a day, for 12 days. No significant differences were observed for the following coagulation proteins and hemostatic markers measured immediately before and after long-term oral vitamin K supplementation: factor II, factor VII, protein C, and thrombin-antithrombin III complex. In conclusion, physiological processing of supplemented vitamin K1 differs in the IM vs PO routes of administration and 12 days of oral vitamin K1 does not alter the concentration of selected vitamin K-dependent coagulation proteins or thrombin-antithrombin complex generation.

Administration, Oral↗
PubMed1994

Comparison of three theories relating facial expressiveness to blood pressure in male and female undergraduates.

We examined differing predictions of how emotional expressions and blood pressure are related. Spontaneous positive and negative facial expressions, resting systolic blood pressure (SBP), and reactive SBP were each measured for 148 male and female undergraduates. The discharge theory of emotions proposes that few expressions will predict higher baseline SBP, and this was found for men. A mismatch theory of emotions proposes that an imbalance between positive and negative expressions will predict higher baseline SBP, and this was supported for women. Finally, coactivation theory proposes that many expressions will predict higher reactive SBP, and this was found for both men and women. These results reconcile previous conflicting findings by clarifying the conditions under which each of these theories may be supported.

Adolescent↗
PubMed1994

Haemophilus influenzae epididymo-orchitis and bacteremia in a man infected with the human immunodeficiency virus.

Haemophilus influenzae is a major bacterial pathogen in patients infected with the human immunodeficiency virus (HIV), although most infections with this organism occur in the respiratory tract. We describe an adult with HIV infection who presented with epididymo-orchitis due to H. influenzae. Eleven prior cases of H. influenzae epididymo-orchitis have been published, but all of these cases occurred in pediatric patients. Little is known about the prevalence of genitourinary tract infections caused by H. influenzae among adults. H. influenzae is a relatively rare cause of bacteremia in adults, but the frequency of H. influenzae bacteremia has been increasing among the HIV-positive population.

AIDS-Related Opportunistic Infections↗
PubMed1993

Suppression and repression in discrepant self-other ratings: relations with thought control and cardiovascular reactivity.

Individual differences in self-other disagreement may tap phenomena that have been notoriously difficult to assess. For example, subjects who believe they possess a trait while their acquaintances disagree may be exhibiting suppression. Further, subjects who deny a trait while acquaintances believe it is present may be displaying repression. In the first study, both subjects and their closest friends rated the subject's hostility level. Suppressors and repressors were expected to exhibit enhanced thought control, and indeed these individuals were more able not to think about white bears when instructed to do so than individuals for whom there was high hostility agreement. However, this was also true for those with low hostility agreement. Only suppressors demonstrated blood-pressure hyperreactivity to a hostility-provoking task as expected; this finding was replicated in a second study employing a different, multi-item measure of hostility, as well as a marker of low Agreeableness.

Adult↗
PubMed1990

Role blurring and the hospital social worker's search for a clear domain.

Hospital social workers strive to define their professional domain to avoid blurring their roles with those of other health care professionals. Hospital social workers are concerned with gaining and retaining recognition by patients, families, and colleagues of their distinct professional contribution. This article reviews the evolution of social workers' roles and functions in hospitals and reflects on the frequently noted discrepancy between self-ascribed roles and those conceded to social workers by other health care professionals. Issues of collaboration in the context of interdisciplinary activity are considered, and the impact of overlapping roles on social work practice is assessed. The value and drawbacks of role ambiguity are discussed, and strategies for role clarification and development of a better-defined domain for social workers in hospitals are recommended.

Hospital Departments↗
PubMed1990

Oat bran supplementation for elevated serum cholesterol.

The National Heart, Lung, and Blood Institute (NHLBI) has recommended intensive dietary treatment as first-line therapy for patients with high cholesterol levels. The NHLBI has also encouraged research into the effectiveness and safety of alternative diets and further study of human behavior as it relates to adherence to diets. Based on these recommendations and previous studies suggesting a hypocholesterolemic effect of oat bran dietary supplementation, 16 family practice outpatients with elevated cholesterol levels were enrolled in a 12 week study designed to assess the practicality and effectiveness of adding four oat bran muffins per day to the diet. Subjects were randomized into immediate intervention and delayed intervention groups. The combined group had a significant decrease in total cholesterol of 7.9 percent (p less than .03) and in LDL-cholesterol of 10.1 percent (p less than .03) but there was no significant difference with respect to lipid changes between the immediate group and the delay group when the delay group was serving as a control for the immediate group. The results taken in conjunction with evidence in the literature indicate that the simple addition of oat bran muffins to the diet of certain family practice outpatients is well tolerated and probably effective in lowering serum total and low density lipoprotein cholesterol.

Edible Grain↗
PubMed1989

Physicians' attitudes on advance directives.

Advance directives provide means for competent individuals to influence treatment decisions in the event of serious illness and subsequent loss of competence, the "living will" being the best known example. Physicians in Arkansas who were identified to be currently engaged in general practice, family medicine, or internal medicine, including its subspecialities (N = 1293), were surveyed to assess attitudes toward and experiences with advance directives. Almost 80% of all respondents expressed a positive attitude and fewer than 2% expressed a negative attitude toward such documents. A majority (55.9%) had actual experience with the instruments in their practices, and 83.5% of these physicians said that their attitude had become more positive as a result of their experience. More frequent employment of advance directives in critical situations was associated with more positive attitudes and experiences. Most of the benefits claimed for advance directives--improved communication and trust, easier and more confident treatment decision, less stress and guilt, and promotion of patient autonomy--were substantiated by the results.

Arkansas↗
PubMed1987

Reduction of adverse drug reactions by computerized drug interaction screening.

Computerized drug-interaction screening systems (CDISS) have been developed as a tool to help decrease the enormous morbidity and expense related to adverse drug interactions. In previous studies the CDISS was used primarily by pharmacists in hospital settings to screen for interactions after the prescription had been written. This study tests the feasibility of family physicians using CDISS before writing the prescription to allow for changes in the prescription while the patient is still in the office. In a 30-day period, 103 patients were screened by family physicians for potential drug-drug, drug-alcohol, and drug-food interactions. Potential drug interactions of varying clinical significance were detected for 71 patients (68.9 percent). The prescription plan was changed for 16 patients (15.5 percent) as a result of using the CDISS. Participating physicians reported that they gained new information in 45.8 percent of the patient encounters, that their awareness of the potential for drug interactions was heightened by participation in this study, and that their exposure to the CDISS was worthwhile as an educational tool. While a few problems, mainly logistic, were noted with the CDISS as used in this study, the authors conclude that with modifications a CDISS can be of great educational and clinical value to the family physician and his or her patients.

Computer Systems↗
PubMed1986

Advance directives in family practice.

Advance directives have emerged in medicine as an important method by which patients can express future treatment wishes. The major reasons medical professionals have been reluctant to use advance directives are not because of theoretical defects with advance directives, but because of procedural difficulties. Confusion over types of advance directives and their legal status will ease with increased knowledge of advance directives by health professionals. Additionally, that they are often formulated in ambiguous terms and under situations where the patient's competence is in question can be minimized. More widespread and effective use of advance directives will occur if the family physician takes an active role in identifying patients for whom an advance directive would be desirable, effectively communicating information about advance directives, advising their patients about the most effective way to state their directive in medically precise terminology, and explaining when necessary the patient's wishes to other medical specialists and family members.

Decision Making↗
PubMed1985

Social work with cancer patients: stresses and coping patterns.

This article reports a study of the special stresses affecting the increasing number of social workers who work with cancer patients and their families. Related literature and research document the universally stressful effects of this chronic and life-threatening illness but offer little knowledge of the job stresses experienced by social workers providing services in hospitals. The nature of the stresses reported by social workers, the adequacy of supports to help them cope with the emotional impact of their work and the need for additional support programs are discussed.

Adaptation, Psychological↗
PubMed1985

Nitrous oxide analgesia for outpatient procedures.

Nitrous oxide analgesia is a safe alternative to parenteral narcotics for outpatient surgical procedures. This type of analgesia is effective, well tolerated by most age groups, easily administered, rapidly reversible and associated with a low incidence of serious side effects. Hypoxia can be prevented by using fail-safe equipment, by observing prescribed limitations on nitrous oxide concentrations and by administering 100 percent oxygen on termination of nitrous oxide administration.

Ambulatory Surgical Procedures↗
PubMed1978

Evolving social work roles in health care:The case of discharge planning.

This paper examines changing definitions of social work's role in health care and the continuing struggle for professional autonomy, in the context of the profession's responsibility for discharge planning. Planning for posthospital care is seen to be a major function of social work today and of traditional importance since social work's inception in the hospital setting. Major role and value conflicts are highlighted in a review of social work's traditional ambivalence toward the role of discharge planner and current recognition of the initial contribution of the profession to the continuing care of hospitalized patients.

Hospital Administration↗
PubMedDate not supplied

The vitamin K content of intravenous lipid emulsions.

Commercially available intravenous lipid emulsions are largely derived from vegetable oils, a natural source of phylloquinone (vitamin K1). We therefore examined the concentration of vitamin K1 in two widely used intravenous lipid emulsions by using a previously validated high performance liquid chromatography technique. The vitamin K1 concentrations of 10% emulsions of Intralipid and Liposyn II were 30.8 and 13.2 micrograms/dL, respectively. The concentration of vitamin K1 in the 20% emulsions of these products was essentially double that in the 10% emulsions. The coefficients of variation between the vitamin K1 content in three different lots of each product were consistently less than 7.0%. The observed concentrations of the vitamin in these lipid emulsions paralleled the predicted content on the basis of the type of vegetable oil(s) used to make the product. The type of vegetable oil used for production therefore seems to be a major determinant of the final vitamin K1 content. The vitamin K1 contained in these intravenous lipid emulsions is substantial and may have great impact on the vitamin K status of the recipient.

Chromatography, High Pressure Liquid↗