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P A Murphy

Publications and source records attributed to P A Murphy.

At least 19 recordsLinked to original sources
PubMed1992

Nurses' attitudes toward patients with AIDS and AIDS-related risk factors.

Three variables were experimentally manipulated by simulation measurement using six vignettes in a completely randomized, partial hierarchical, experimental design: medical diagnosis (AIDS v. non-AIDS), sexual orientation (heterosexual v. homosexual) and intravenous drug-use history (IVDU v. non-IVDU). Following each vignette, the same Prejudicial Evaluation Scale (PES) and Social Interaction Scale (SIS) were used to measure nurses' attitudes toward patients and their willingness to interact with patients. Vignette questionnaires were randomly assigned to 360 acute-care nurses. Although sexual orientation was found not to influence PES and SIS scores, an AIDS medical diagnosis and a history of intravenous drug use were found to increase nurses' negative attitudes toward patients significantly and reduce their willingness to interact with patients. Study findings did not vary according to nurses' age, academic preparation or previous practice experience with patients with AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1992

T cell receptor-independent immunosuppression induced by dexamethasone in murine T helper cells.

The immune and inflammatory responses are largely inhibited by glucocorticosteroids. In thymocytes, for example, glucocorticosteroids cause apoptosis, whereas they suppress the activity of phospholipase A2 and the production of eicosanoids in tissues actively engaged in inflammation. The immunosuppressive action of dexamethasone (DEX) was studied in vitro by employing a model cell system, namely the murine Th2 clone D10.G4.1 (D10) and its clonotypic anti-T cell receptor (TCR) mAb 3D3. Although the proliferative response of D10 cells to 3D3 stimulation was not affected by DEX, the costimulation provided by IL-1 was dramatically inhibited. Substitution of 3D3 by exogenous IL-4 (as the IL-1 costimulant) failed to prevent the inhibition of proliferation caused by DEX. Yet, when 3D3-mediated stimulation of TCR was supplemented with IL-2, D10 cells were capable of proliferating, even in the presence of DEX. Thus, TCR stimulation on D10 cells remained intact and their resulting propagation was not compromised by DEX treatment. These results provide evidence that immunosuppression caused by DEX is TCR independent and involves an early cytokine-signalling event.

Animals↗
PubMed1992

Empathy of intensive care nurses and critical care family needs assessment.

In this study we explored the relationship between the empathy of intensive care unit (ICU) nurses and their ability to assess accurately the perceived needs of family members of patients hospitalized in ICU settings. Thirty family needs were studied by using Molter's 1983 revision of the Critical Care Family Needs Inventory (CCFNI). Data consisted of 92 pairs of CCFNI responses obtained from 92 family members of ICU patients and 60 ICU nurses providing direct care for these patients. Multiple regression analysis was performed to determine the extent to which empathy and nursing experience contribute to accurate assessment of the needs of ICU family members. The more emphatic ICU nurses were, the greater their ability to assess ICU family members' needs accurately on six of the needs studied (p less than or equal to 0.05). Length of nursing experience negatively affected the nurse's ability to assess three of the ICU family members' needs accurately (p less than 0.05).

Adult↗
PubMed1991

Temperature is a powerful promoter of interleukin 2 transcription.

Elevated temperature has profound effects on the immune system, particularly by increasing T-cell proliferation rates, interleukin 1 (IL-1)-driven secretion of IL-2, and primary antibody responses to T-dependent antigens. Therefore, this study shows, in detail, the effects of incubation temperature (29 degrees C to 41 degrees C) on proliferation, IL-2 secretion, and IL-2 mRNA expression in both a murine thymoma cell line (EL4-6.1) and in nontransformed murine splenocytes. Temperature was found to be a positive regulator of IL-2 secretion whether or not IL-1 was part of the activation signal. Parallel effects were observed at the level of IL-2 gene expression. Messenger RNA was quantitated with a novel system, using solution hybridization followed by detection of RNA-DNA complexes by enzyme immunoassay. The time to onset of IL-2 mRNA expression was inversely related to temperature, and mRNA levels increased 20- to 50-fold with increases in average incubation temperature from 29 degrees C to 39 degrees C. This effect was observed whether cells were incubated at constant temperature or exposed intermittently to elevated temperature. Over the same intervals of time and temperature, mRNA levels for tau-actin and beta-tubulin remained relatively constant. Taken together, these findings suggest that temperature-mediated augmentation of IL-2 secretion does not require the presence of IL-1, and that the effect occurs at a pretranslational level.

Animals↗
PubMed1991

Evidence of peroxisomes and peroxisomal enzyme activities in the oleaginous yeast Apiotrichum curvatum.

The presence of peroxisomes and peroxisomal enzyme activities were investigated in the oleaginous yeast Apiotrichum curvatum ATCC 20509 (formerly Candida curvata D.) Catalase, a marker enzyme for peroxisomes, was measured in cell-free extracts prepared by sonication. The nature of the carbon and nitrogen sources in the growth medium greatly affected catalase activity. Cells grown on corn oil had high specific activity of catalase, but those grown on glucose, sucrose, or maltose had low specific activity. High specific activity of catalase was measured in cultures grown on media that supported poor growth (with soluble starch as carbon source or with methylamine, urea, or asparagine as nitrogen source). Peroxisomes from cells grown on corn oil were separated from other subcellular fractions in a discontinuous sucrose gradient. Major peaks of activity of fatty acid beta-oxidation and of two key enzymes in the glyoxylate cycle were found in fractions containing peroxisomes, but not in fractions corresponding to the mitochondria. Peroxisomal beta-oxidation showed equivalent activity with palmitoyl CoA or n-octanoyl CoA as substrate. Mitochondria did not seem to contain NAD-linked glutamate dehydrogenase. Peroxisomes with a homogeneous matrix and core surrounded by a single-layer membrane were observed with an electron microscope in cells grown on corn oil, but not in those grown on glucose. Staining with 3,3'-diaminobenzidine revealed that catalase activity was located in peroxisomes. Peroxisomes in this oleaginous yeast play important roles in lipid metabolism.

Candida↗
PubMed1991

Critical care family needs in an urban teaching medical center.

This is a descriptive study of the relative importance of needs as reported by 213 family members of 114 patients hospitalized in critical care units of a large, urban, teaching, medical center. In this study we used Molter's Critical Care Family Needs Inventory (revised), an instrument that has been used in other similar investigations, but never before in such a large sample or one with similar demographics. In general, the findings were consistent with those in previous studies using the Critical Care Family Needs Inventory. One striking difference was the relatively low ranking accorded by this sample to the need "to feel there was hope." Parents, spouses, siblings, adult children, and "significant others" ranked their needs in strikingly similar ways. Family members of critically ill patients need two things most: to have honest, intelligible, and timely information and to feel assured that their loved one is being cared for by competent and caring people. Clinical, educational, and research implications are identified and briefly discussed.

Academic Medical Centers↗
PubMed1990

Quantitative detection of messenger RNA by solution hybridization and enzyme immunoassay.

A novel nucleic acid detection technique is described for the quantitative measurement of eukaryotic mRNA in biological samples. The procedure involves two steps: a hybridization reaction in solution with a biotinylated cDNA probe, and a conventional enzyme immunoassay that uses a monoclonal antibody for DNA.RNA hybrids to detect the specific mRNA.cDNA complexes. The method has comparable sensitivity to 32P-based methods and yields results that are quantitative and highly reproducible. Furthermore, the test can be performed using unfractionated cytoplasm without the need for extraction with organic solvents. This technique provides a rapid and quantitative method for studying changes in cellular mRNA levels, and it is suitable for testing large numbers of samples.

Antibodies, Monoclonal↗
PubMed1990

Lipid metabolism and cell composition of the oleaginous yeast Apiotrichum curvatum grown at different carbon to nitrogen ratios.

Apiotrichum curvatum ATCC 20509, an oleaginous yeast that can accumulate up to 60% of its cellular dry weight as intracellular lipid when grown with excess carbon, was grown in nitrogen-limited, balanced, and lactose-free medium with asparagine as nitrogen source and lactose as carbon source. Biomass and lipid accumulation were measured, cell composition was analyzed, and catalase activity was followed as marker enzyme for peroxisomes. The organism accumulated 54% of its dry weight as total cellular lipid when grown under nitrogen limitation and accumulated only 20-25% of its dry weight as lipid when grown in balanced medium. When starved for carbon, cells utilized endogenous lipid and carbohydrate as carbon and energy sources; the intracellular contents of lipid and carbohydrate decreased by 31 and 26%, respectively. Intracellular carbohydrates also seemed to be used as intermediates for lipid accumulation and lipid turnover. Catalase activity was strongly induced (over 10-fold increase in specific activity) when cells metabolized endogenous lipid. The lipid content of cells was inversely related to catalase activity and to intracellular protein or total nitrogen content. Lipid content showed no correlation with intracellular carbohydrate content.

Candida↗
PubMed1990

Critical care family needs: nurse-family member confederate pairs.

In this study we explored the relationship between critical care family members' perceived needs and the assessment of these needs by a confederate sample of intensive care unit (ICU) nurses. Family needs were measured by using Molter's revised Critical Care Family Needs Inventory. Data consisted of 92 confederate pairs of Critical Care Family Needs Inventory responses obtained from 92 family members of adult patients hospitalized in a variety of ICUs and 49 ICU nurses providing direct care for these patients. Paired t tests (two tailed) were calculated to detect significant differences between confederate pairs of family members' perceptions and ICU nurses' assessments of the importance of the needs studied. Family members' perceptions and ICU nurses' assessments of the most and least important critical care family needs were identified. Significant (p less than 0.001 to p less than 0.05) differences were detected between confederate pairs of family members' perceptions and ICU nurses' assessments of the importance of 15 (50%) of the critical care family needs studied. Therefore, it appears that these nurses were only moderately accurate in their assessments of critical care family needs. Implications for nursing practice, education, and research were identified and discussed.

Adolescent↗
PubMed1989

Blastomycosis.

Explore the source record for details and available documents.

Biopsy↗
PubMed1989

Acute-phase behavior of factor VIII procoagulant and other acute-phase reactants in rabbits.

We measured the plasma concentrations of factor VIII procoagulant (FVIII:C) in rabbits in two laboratory models of inflammation and after injections of purified homologous interleukin 1 (IL-1). The mean FVIII:C activities 2-4 days following the intramuscular injection of turpentine were significantly elevated, as were the concentrations of fibrinogen and C-reactive protein (CRP). By contrast, rabbits given 50 ng of bacterial lipopolysaccharide intravenously developed increased levels of FVIII:C but not of fibrinogen or CRP. We then studied plasma levels of FVIII:C, fibrinogen, and CRP after injections of either form of purified rabbit IL-1. If the rabbits' temperatures were monitored, FVIII:C levels increased in a log dose-related manner. This effect was not seen unless the rabbits were restrained and was seen in restrained rabbits even if the temperatures were not monitored. Fibrinogen and CRP levels did not change after IL-1 injections. These findings demonstrate that FVIII:C is an acute-phase reactant as judged by its response to turpentine inflammation or endotoxin injections, and to injections of IL-1 in restrained rabbits. FVIII:C appears to be a more sensitive acute-phase reactant than either fibrinogen or CRP. Neither of the latter proteins responded to low-dose endotoxin injections nor to either form of purified homologous IL-1. The doses of IL-1 given did cause fever, neutrophil leukocytosis, and hypoferremia.

Acute-Phase Proteins↗
PubMed1987

Interleukin 1-driven secretion of interleukin 2 is highly temperature-dependent.

To investigate the temperature dependence of T lymphocyte activation, we have examined the IL 1-induced secretion of IL 2 by the murine T lymphoma cell line LBRM-33-1A5. During 24-hr incubations, there are modest increases in IL 2 secretion as culture temperatures are increased from 33 degrees to 37 degrees C, but IL 2 secretion declines at higher temperatures. However, the kinetics of IL 2 release during the first 8 hr of culture are highly temperature-dependent. The rate of IL 2 release increases linearly with temperature over the range from 33 degrees to 41 degrees C, demonstrating temperature coefficients (Q10) greater than 70. In contrast, IL 2-promoted proliferation of a continuous T cell line is much less temperature-dependent with Q10 values of less than 4.0.

Animals↗
PubMed1987

Subcellular localization and capacity of beta-oxidation and aldehyde dehydrogenase in porcine liver.

Porcine hepatocyte organelles were separated by isopycnic sucrose gradient centrifugation from livers of 6-month-old Yorkshire pigs. The presence of a peroxisomal palmitoyl-CoA oxidizing system and a peroxisomal NAD:aldehyde dehydrogenase (ALDH) with high Km for acetaldehyde was demonstrated. Peroxisomal palmitate oxidizing capacity was found to be equal to that of the surviving mitochondria. The high Km isozyme of ALDH was mainly located in the mitochondria (54%), with a significant portion in the peroxisome (32%). Remaining activity is distributed among the microsomes (8.3%) and cytosol (4.6%). The low Km isozyme was confined almost exclusively to the mitochondria. ALDH may exist in the peroxisome as a detoxification mechanism and contribute to shorter half-lives of reactive aldehydes in the cell. Species differences are discussed.

Aldehyde Dehydrogenase↗
PubMed1986

Accumulation of indium-111-labeled neutrophils and gallium-67 citrate in rabbit abscesses.

A rabbit abscess model was developed to study the effect of abscess age on the accumulation of indium-111-labeled neutrophils ([111In]N) versus gallium-67 citrate (67Ga). Abscesses 1-2 hr, 6-8 hr, 24 hr, and 7 days old were induced by subcutaneous injection of autoclaved colon contents prior to i.v. administration of either [111In]N or 67Ga. Radioactivity in the abscesses was determined 48 hr postinjection. Accumulation of [111In]N was inversely proportional to abscess age. Seven-day-old abscesses were inconsistently seen on [111In]N scans. In contrast, 67Ga accumulation was not affected by abscess age and all abscesses could be identified on a scan 48 hr postinjection. Scans with [111In]N were clearly superior to 67Ga scans for demonstrating early abscesses. Since 67Ga accumulated to a greater extent than [111In]N in abscesses 7 days old, it may be a superior imaging agent for older abscesses.

Abscess↗