Biomedical subjects

T F Wright

Publications and source records attributed to T F Wright.

5 recordsLinked to original sources

PubMed1996

Laparoscopic versus open appendectomy.

This prospective clinical study was done because our initial retrospective review suggested that laparoscopic appendectomy (LA) offers no significant advantages over open appendectomy (OA) yet is significantly more expensive. From July 1992 to August 1993, 57 patients were approached preoperatively for randomization to either LA (n = 19) or OA (n = 18). There were no statistically significant differences between the LA and OA groups in operative risk: mean age, 28 +/- 2 vs 26 +/- 2 years; percent female, 26% vs 22%; body mass index, 24 +/- 0.8 vs 26 +/- 1.2 kg/m2. All patients were either ASA class I or class II, 78% in each group being class II. The differences between the LA and OA groups in mean operating time required (93 +/- 12 vs 87 +/- 8 minutes), postoperative intramuscular narcotic analgesic usage (24 +/- 6 vs 26 +/- 6 hours), postoperative hospital stay (57 +/- 12 vs 66 +/- 10 hours), and return to normal activity (20 +/- 6 vs 14 +/- 3 days) were also not significant. However, LA was much more expensive because of higher operating room charges. The mean total hospital bill was $4,600 +/- $160 for the LA group and $1,700 +/- $70 for the OA group. This prospective study corroborated our previous analysis. Laparoscopic appendectomy is safe, effective, and expensive and overall has no greatly significant advantages over open appendectomy.

Adolescent↗

PubMed1994

The effects of native LDL and oxidized LDL on EDRF bioactivity and nitric oxide production in vascular endothelium.

Low-density lipoprotein (LDL) and oxidized low-density lipoprotein (OxyLDL) have previously been shown to inhibit vasorelaxation caused by endothelium-derived relaxing factor (EDRF). The purpose of the present study was to directly determine the effects of LDL and OxyLDL on EDRF bioactivity and nitric oxide (NO) production in vascular endothelium to further understand the mechanism whereby lipoprotein alters vascular reactivity. Cultured bovine aortic endothelial cells were incubated with either LDL or OxyLDL for 1 hour. After washing the cells free of lipoprotein, agonist-stimulated (bradykinin; BK) EDRF bioactivity and NO content of the effluent were quantitated. These results were compared with control cells not exposed to lipoprotein. In a second series of experiments, the effects of LDL and OxyLDL on EDRF-mediated increases in cyclic guanosine monophosphate (cGMP) in a reporter fibroblast cell line were determined. Last, the direct effects of LDL on NO-induced vasodilation of isolated coronary artery rings were determined by using standard in vitro isometric recording methods. LDL and OxyLDL significantly decreased EDRF bioactivity but not NO production by endothelial cells. When expressed as percent relaxation of the biodetector per mole of NO produced, both LDL and OxyLDL resulted in the release of a significantly less-potent vasodilator than that derived from control cells. In the reporter fibroblast experiments, there was no significant difference in the amount of cGMP generated by fibroblasts in response to medium from control and lipoprotein-treated cells. In isolated ring experiments, LDL did not directly alter NO vasorelaxation. We conclude that both LDL and OxyLDL inhibit EDRF-induced vasorelaxation by complex mechanisms other than the direct inhibition of NO synthesis by endothelial cells or extracellular inactivation of EDRF. LDL and OxyLDL may result in the release of a less potent NO-containing relaxing factor by altering the metabolism of an endogenous nitrosovasodilator.

Animals↗

PubMed1992

EDRF and nitric oxide production in cultured endothelial cells: direct inhibition by E. coli endotoxin.

Recent studies have yielded contradictory interpretations about the influence of gram-negative endotoxin on endothelium-derived relaxing factor (EDRF). We tested the hypothesis that Escherichia coli endotoxin exerts primary facilitatory or, alternatively, inhibitory actions on EDRF release and the synthesis of either nitric oxide or a nitroso compound in cultured endothelial cells. Bovine aortic endothelial cells were grown on microcarrier beads and either exposed acutely (30 min) to E. coli endotoxin or incubated with endotoxin for 1 h followed by a 1-h wash (prolonged exposure). EDRF bioactivity was measured under basal, bradykinin-stimulated, and A23187-stimulated conditions using standard isometric tension recordings. EDRF-derived nitric oxide was quantitated using a specific chemiluminescence technique. Endotoxin (0.005-5 micrograms/ml) decreased EDRF bioactivity and nitric oxide production under both basal and bradykinin-stimulated conditions after prolonged, but not acute, exposure. A23187-stimulated EDRF bioactivity and nitric oxide production were minimally, albeit significantly, reduced after endotoxin. The present results demonstrate that EDRF activity and nitric oxide production are decreased in vascular endothelial cells exposed to endotoxin. Endotoxin itself failed to directly stimulate EDRF release from endothelium. Alternative sources of nitrovasodilators, endothelium-independent effects, or release of other vasoactive mediators by endotoxin may be responsible for systemic hypotension during in vivo endotoxemia.

Animals↗

PubMed1992

A comparison of epidural and non-epidural anesthesia and analgesia in total hip or knee arthroplasty patients.

This retrospective study explores a number of variables encountered with the use of either epidural or non-epidural anesthesia and analgesia. Postoperative mobility, amount of narcotic used, incidence of blood transfusion, length of stay, and presence of urinary retention, pruritus, nausea and vomiting, or respiratory depression were compared in a group of 101 consecutive patients scheduled for total hip or knee arthroplasty. Fifty-two patients received epidural anesthesia and analgesia; the remaining 49 received non-epidural anesthesia, followed by standard IM/IV postoperative analgesia. Epidural patients required significantly less narcotic than the non-epidural group. There were significantly fewer blood transfusions in the epidural group; however, epidural patients had significantly increased incidence of urinary retention and pruritus. The use of epidural anesthesia and analgesia for total hip and knee arthroplasty patients has definite merit, but is most safely administered in a monitored, skilled nursing unit.

Aged↗

PubMedDate not supplied

Hardiness, stress, and burnout among intensive care nurses.

The purposes of this study were to determine whether hardiness is a predictor of burnout and whether it can buffer the effect of stress on burnout. Thirty-one registered nurses who work in intensive care units completed the Hardiness test, the Nursing Stress scale, and the Tedium scale. Descriptive statistics, correlational statistics, t tests, analysis of variance, and hierarchical multiple regressions were used to analyze the data. Results indicated that hardiness and burnout had a significant inverse relationship (r = 0.66). Stress and the stress-hardiness interaction term accounted for 29% of the variance in burnout scores. This study found hardiness to be a predictor of burnout and a buffer in the stress-burnout relationship. Furthermore, the relationship between hardiness and stress was found to be stronger than that between stress and burnout. Further study is needed to verify that hardiness is a stress mediator in nursing and to determine how to best promote hardiness in nurses.

Adult↗