Search PubMed⌕ Search

Biomedical subjects

M J Stewart

Publications and source records attributed to M J Stewart.

At least 73 records · Page 4Linked to original sources
PubMed1996

Assessing functional status of elderly adults via microcomputer.

Geriatric adults (at least 65 years of age) completed the Functional Status Questionnaire twice, first using the original paper-and-pencil format and again using one of six computer-based interactive methods. Scoring via original and computer-based methods was identical. Satisfaction with computers was high. Of the interactive methods, touchscreen required least training and questionnaire completion time and was rated most useful.

Activities of Daily Living↗
PubMed1996

Amount of psychological stress reported by high school volleyball officials.

All volleyball officials registered with a state high school activities association in a midwestern state were surveyed at the end of the volleyball season to assess their self-reported, psychological stress. Of 470 officials contacted, 353 (75%) responded by filling out a simple 5 point rating scale. The mean rating of stress was 2.3 (SD = .6) (between "very little" and "a moderate amount") which is similar to past findings for certified, amateur baseball and softball umpires.

Adolescent↗
PubMed1996

Distribution of messenger RNAs for aldehyde dehydrogenase 1, aldehyde dehydrogenase 2, and aldehyde dehydrogenase 5 in human tissues.

BACKGROUND: The distribution of aldehyde dehydrogenases in human tissues is incompletely understood, in part because of technical limitations of gel electrophoretic and other enzyme assay methods used previously and because of the instability of the enzymes. Since these enzymes participate in detoxification of endogenous and exogenous compounds, including ethanol, their tissue distribution may be relevant to the toxicology of a number of substances and to the medical consequences of alcoholism. METHODS: The abundance of mRNA for aldehyde dehydrogenase 1 (ALDH1), aldehyde dehydrogenase 2 (ALDH2), and aldehyde dehydrogenase 5 (ALDH5) was determined by Northern blotting using poly A+ RNA from 16 adult human tissues and 5 fetal tissues. RESULTS: The highest levels of ALDH1 mRNA were found in liver, kidney, muscle, and pancreas. ALDH2 and ALDH5 were expressed in a larger number of tissues than ALDH1, with highest levels in liver, kidney, muscle, and heart. Fetal heart, brain, liver, lung, and kidney expressed ALDH2 and ALDH5, while ALDH1 was present mainly in fetal liver, kidney, and lung. CONCLUSIONS: The results are in general agreement with the distribution of enzymes studied in a limited number of tissues in the past, with the exception that the ALDH1 activity reported to exist in heart and brain may, in fact, be ALDH5. The only mRNA detected in placenta was that for ALDH5. This study extends the knowledge of the expression of these enzymes to several tissues not previously studied and establishes the tissue distribution of the new enzyme ALDH5.

Adult↗
PubMed1996

Smoking among disadvantaged women: causes and cessation.

This study aimed to identify social-psychological factors associated with smoking and smoking cessation among disadvantaged women. Individual and group interviews were conducted with disadvantaged women in Atlantic Canada. Participants were predominantly poor, unemployed, geographically isolated, and single parents. The factors associated with smoking included coping with stresses, loneliness, powerlessness, low self-efficacy, social pressures, and addiction. Support from peers (i.e., women in similar circumstances) and partners was considered important. Health professionals and traditional cessation programs were not perceived as supportive. Participants viewed women's centres and women's agencies as appropriate deliverers of cessation programs. Methodological issues are discussed.

Adaptation, Psychological↗
PubMed1996

Infective endocarditis of the tricuspid valve in an orthotopic heart transplant recipient.

A 43-year-old orthotopic heart transplant recipient had coagulase-negative staphylococcus endocarditis 26 weeks after the operation. A diagnosis of endocarditis was confirmed and followed up by serial transoesophageal echocardiography. Treatment with intravenous gentamycin and vancomycin cured her endocarditis, and a 2.5 cm vegetation regressed significantly. She has been well since and, at 14 months after transplantation, was back to her normal activities. Although repeated blood culture yielded only intermittent light growths of coagulase-negative staphylococci, there were several positive samples. In a setting of infective features, light growths of coagulase-negative staphylococcus should be taken seriously if repeatedly positive in heart transplant recipients or other immunocompromised patients. Transesophageal echocardiography offers significant advantages over the transthoracic modality in suspected endocarditis.

Adult↗
PubMed1996

Social support in children with a chronic condition.

This study used a descriptive exploratory design to describe social support in children with a chronic condition and how children use social support in coping with everyday demands and demands related to their condition. Participants comprised 62 school-aged children (16 with diabetes, 16 with cystic fibrosis, 15 with spina bifida, and 15 with no chronic illness). Data were collected about their social-support networks, the support functions provided by the networks, and their satisfaction with support. The children also described the social support they received and their use of social support as a coping strategy in specific stressful situations. The healthy children had the largest support networks overall and the largest peer networks. Children with spina bifida had the smallest networks overall and the smallest number of peers in their networks. Healthy children reported more support overall than the children in the illness groups. Both the healthy children and the children with a chronic condition described academic issues as the main source of everyday stress. Children with a chronic condition identified restriction due to illness as the key illness-related stressor. Children with a chronic condition reported more stress and more support-seeking in everyday stressful situations than in illness situations. The results will guide the design of a future social-support intervention for children with a chronic condition.

Adaptation, Psychological↗
PubMed1995

The novel aldehyde dehydrogenase gene, ALDH5, encodes an active aldehyde dehydrogenase enzyme.

The mRNA for the novel aldehyde dehydrogenase 5 (ALDH5) gene was detected in HuH7 hepatoma cells. The cells also expressed cytosolic aldehyde dehydrogenase (ALDH1) mRNA, but no mitochondrial aldehyde dehydrogenase (ALDH2) mRNA. Extracts of the hepatoma cells contained an enzymatic activity with an isoelectric point similar to that of ALDH1. This enzyme activity was insensitive to inhibition by disulfiram, a potent inhibitor of ALDH1. The enzyme was active with short chain aldehydes (acetaldehyde and propionaldehyde) and NAD+, but not with NADP+, and the activity was higher in the mitochondrial pellet than other cell fractions. These studies demonstrate the expression of ALDH5 mRNA in a human hepatoma and suggest that the gene product is enzymatically active and probably resides in the mitochondria.

Aldehyde Dehydrogenase↗
PubMed1995

The contributions of nursing science to social support.

Nurse scientists have contributed to the theoretical development of social support through concept refinement, creation of measures, and intervention research. Nevertheless, deficiencies persist pertaining to the conceptualization of the construct and the design of intervention studies. Cultural, technological and political contexts have an effect on social support. The significance of social support, nurses' scholarly contributions, and continuing conceptual and methodological challenges are analysed.

Health Policy↗
PubMed1995

Living with haemophilia and HIV/AIDS: support and coping.

This paper describes sources and types of support, appraisal of support, and use of social support as a strategy for coping with Acquired Immune Deficiency Syndrome (AIDS)-related stresses. Thirty people with haemophilia, 23 family caregivers and 17 bereaved relatives participated. The study was conducted in two stages: individual interviews and mailed questionnaires. The key coping strategies used were 'normalizing personal relationships' and 'seeking informational support'. Informational support was provided by health professionals and practical aid by relatives. Respondents reported insensitivity, prejudice and avoidance from others. Participants needed peers for emotional and affirmational support, and professionals for informational support. The preferred intervention was support groups, co-led by professionals and peers.

Adaptation, Psychological↗
PubMed1995

Hormonal and chemical influences on the expression of class 2 aldehyde dehydrogenases in rat H4IIEC3 and human HuH7 hepatoma cells.

We studied the effect a variety of hormones and chemical stimuli on the activity of low Km aldehyde dehydrogenase (ALDH) in rat H4IIEC3 hepatoma cells and ALDH activity in human HuH7 hepatoma cells. The low Km enzyme in H4IIEC3 cells reflects ALDH2 activity, and the ALDH activity in HuH7 likely represents ALDH5. Of the steroid hormone family, thyroid hormone, progesterone, and dihydrotestosterone increased low Km ALDH activity approximately 50%, whereas dexamethasone and estradiol had little effect. Insulin decreased the activity of low Km ALDH. None of these hormones affected the activity of ALDH in HuH7 cells. Among second messengers, 8-bromo-cAMP and A23187 increased low Km ALDH activity; HuH7 ALDH activity again was unchanged. Exposure of the cells to 22 mM ethanol reduced low Km activity by approximately 20%, whereas hydrogen peroxide, tumor necrosis factor-alpha, and interleukin-1 beta had little effect. Ultraviolet light increased the HuH7 ALDH activity. Retinaldehyde or retinolc acid reduced the HuH7 ALDH activity, but had no effect on low Km ALDH activity. These data suggest that low Km ALDH2 can be regulated by hormones and may not be constitutive as previously thought, and that the HuH7 ALDH is regulated differently.

Alcoholism↗
PubMed1995

Reduced diurnal variation of blood pressure in non-insulin-dependent diabetic patients with microalbuminuria.

In essential hypertension reduced diurnal blood pressure (BP) variation is associated with an increased prevalence of target organ damage. We have examined diurnal BP variation in 25 microalbuminuric (MA) and 19 normoalbuminuric (NMA) patients with non-insulin-dependent diabetes and related albumin excretion rate (AER) to diurnal BP variation in the microalbuminuric group. There were no significant differences in age, body mass index (BMI), renal function, diabetic control, clinic or daytime ambulatory BP between the groups. Night-time SBP was higher (MA 145 mm Hg (137-153), NMA 132 mm Hg (125-139); P = 0.019) in the microalbuminuric group while the diurnal variation as assessed by the day-night dip in BP was significantly reduced in the microalbuminuric group (systolic: (mean (95% confidence intervals) MA 4.7% (1.7-7.7), NMA 12.8% (9.5-16.0), p = 0.001; diastolic: MA 6.5% (3.0-10.0), NMA 14.5% (10.2-18.8), P = 0.007). Within the microalbuminuric group, the systolic dip in BP was inversely related to the AER (r = -0.48, P = 0.015). Reduced diurnal BP variation and high night-time BP may contribute to target organ damage in diabetes.

Aged↗
PubMed1995

The accuracy of automated blood pressure measuring devices in patients with controlled atrial fibrillation.

OBJECTIVE: To determine whether automated blood pressure measuring devices can measure blood pressure accurately in patients with atrial fibrillation. DESIGN: Comparison of the accuracy of two electronic sphygmomanometers [Takeda UA-751 (Takeda) and Copal UA-251 (Copal)] and two ambulatory blood pressure monitors [Accutracker 1 (Accutracker) and SpaceLabs 90207 (SpaceLabs)] with that of a trained observer using a Hawksley random-zero sphygmomanometer (Hawksley), using the sequential same-arm technique. SETTING: University teaching hospital: medical wards and outpatient department. SUBJECTS: Twenty-eight patients, mean +/- SD age 72 +/- 9 years, blood pressure range 90-158/40-96 mmHg, in atrial fibrillation with a controlled ventricular rate. MAIN OUTCOME MEASURES: The proportion of machine readings > 5 mmHg different from the Hawksley reading was compared with that obtained by three sequential Hawksley measurements. The variability of each measuring method was assessed by determining the SDD for the paired readings from each device. RESULTS: Five per cent of Takeda, 5% of Copal, 14% of Accutracker and 21% of SpaceLabs readings could not be obtained. Sequential testing with the Hawksley resulted in an accuracy at the 5-mmHg level of (systolic/diastolic) 79/79%, compared with 64/54% (P < 0.05 for diastolic) for the Takeda, 68/75% (NS) for the Copal, 50/36% (P < 0.01 for both) for the Accutracker and 50/29% (P < 0.01 for systolic, P < 0.001 for diastolic) for the SpaceLabs. Intrapatient variability, as assessed by SDD, was 8.3/8.6 mmHg for the Hawksley, similar to that for the Copal (7.7/7.3 mmHg) but higher for the Takeda (11.2/19.7 mmHg), the Accutracker (22.4/26.3 mmHg) and the SpaceLabs (7.5/14.8 mmHg). CONCLUSIONS: Accurate measurement of blood pressure with an electronic device is possible in patients who have atrial fibrillation; the Copal UA-251 provides a satisfactory level of accuracy. However, the marked difference between devices and the limited accuracy of the other machines tested here demonstrates the need to ensure that such devices are of proven accuracy in this patient group.

Aged↗
PubMed1995

Role for E2F1 in p210 BCR-ABL downstream regulation of c-myc transcription initiation. Studies in murine myeloid cells.

Experiments were performed to elucidate the mechanism through which p210 BCR-ABL, by its downstream signals, regulates c-myc messenger RNA expression in hematopoietic cells. We studied a model system in which stable expression of p210 BCR-ABL in interleukin-3 (IL-3) dependent murine myeloid cell lines led to growth factor independent transformation. Active c-myc transcription was observed in p210 BCR-ABL transformed cells by nuclear run-on assay, and in heterologous reporter assays performed with the 5' regulatory region of murine c-myc linked to firefly luciferase. Transcription initiation occurred primarily from the P2 promoter in p210 BCR-ABL transformed cells. Cis and trans elements responsible for transcription initiation from the c-myc P2 promoter were studied. Expression of E2F1 protein in p210 BCR-ABL transformed cells accounted, in part, for binding to the E2F site of the P2 c-myc promoter. The functional importance of E2F1 expression in p210 BCR-ABL transformed cells toward c-myc transcription was established in reporter assays performed with the P2 c-myc promoter containing either wild-type or mutant E2F sites. Mutation of the E2F motif of P2 5' c-myc reduced activity of the promoter by 50%. By gel mobility shift, E2F1 was found in P2 c-myc band shift complexes along with the cyclin-dependent kinase 2. Therefore, coupling of E2F to components of the retinoblastoma-cyclin pathway defines a route from p210 BCR-ABL to c-myc transcription, which is required for p210 BCR-ABL transformation.

Animals↗
PubMed1994

A novel transcriptional suppressor located within a downstream intron of the BCR gene.

A reciprocal translocation between chromosomes 9 and 22 creates the Philadelphia (Ph1) chromosome in chronic myelogenous leukemia. This translocation results in the fusion of the ABL and the BCR genes to form a BCR/ABL fusion gene, the product of which has a greatly increased protein tyrosine kinase activity in comparison with the normal ABL protein. The chromosome 22 translocation breakpoints are concentrated within a 5.8-kilobase region named the major break-point cluster region (Mbcr). Gel mobility shift and DNase I footprinting assays have defined binding sites for three proteins, BIF 1-3 (BCR intron factors 1-3), lying within a 427-base pair fragment of the Mbcr. This 427-base pair fragment functions as a transcriptional silencer with both the BCR as well as a heterologous promoter. The silencing is position- and orientation-independent. The transcriptional effects are greatest in chronic myelogenous leukemia cells, decreased in HeLa and B-cells, and absent in T-lymphocytes. Gel mobility shift assays show a corresponding difference in pattern when the T-lymphocyte nuclear extract is compared with other cell lines. The Mbcr appears to contain a novel group of transcriptional silencers that share a common binding motif with a recently described suppressor in the mouse Adh-1 gene.

Base Composition↗
PubMed1994

Mitogenesis and protein synthesis: a role for ribosomal protein S6 phosphorylation?

It has been known for 20 years that the ribosomal protein S6 is rapidly phosphorylated when cells are stimulated to grow or divide. Furthermore, numerous studies have documented that there is a strong correlation between increases in S6 phosphorylation and protein synthesis, leading to the idea that S6 phosphorylation is involved in up-regulating translation. In an attempt to define a mechanism by which S6 phosphorylation exerts translational control, other studies have focused on characterizing the sites of phosphorylation of this protein and its location within the ribosome. Recent data show that S6 is a protein which may have diverse cellular functions and is essential for normal development, and that it may be involved in the translational regulation of a specific class of messages.

Amino Acid Sequence↗
PubMed1994

Antibody-facilitated macrophage killing of Trypanosoma musculi is an extracellular process as studied in several variations of an in vitro analytical system.

Antibody-facilitated macrophage (MP) destruction of Trypanosoma musculi involves ingestion and intracellular degradation of the parasites. It is likely, however, as we show here, that death of the trypanosomes is extracellular and it is the corpses that are ingested by MPs. We have utilized both peritoneal MPs and a cloned line (WLG 5) of mouse MPs to analyze the killing of T. musculi. Both types of MP were more effective when activated by interferon-gamma (IFN-gamma) rather than lipopolysaccharide (LPS). When activated by both, LPS diminished the killing activity stimulated by IFN-gamma, perhaps by changing the spectrum of lysins/toxins released by the MPs. Nitric oxide (NO) was found to be toxic for T. musculi and to be responsible, in part, for MP killing of the parasites. Although antibody and complement in concert caused lysis of T musculi, complement was not required for MP killing of the parasites. In the course of this investigation, we developed an in vitro system, involving line 5 MPs and plasma from infected mice containing resident parasites, that should prove satisfactory for detailed analyses of the mechanisms of the antibody-dependent, cell-mediated cure of T. musculi infection.

Animals↗