Search PubMed⌕ Search

Biomedical subjects

A Mitchell

Publications and source records attributed to A Mitchell.

At least 217 records · Page 12Linked to original sources
PubMed1990

A randomized controlled trial of a nursery ritual: wearing cover gowns to care for healthy newborns.

The routine wearing of individual cover gowns by nurses and visitors for direct care of healthy newborns was usual practice on the maternity ward of a regional referral center. We conducted a randomized trial in which cover gowns were not provided for care of infants in the experimental group (n = 222), but were maintained for control infants (n = 230). The principal outcome measured was Staphylococcus aureus colonization of the newborn nares or umbilicus on day 3 or day of discharge. Twenty percent (n = 51) of the experimental group (no gown) had a positive culture compared with 21 percent (n = 47) of the controls. Of the infants with positive cultures, two in each group exhibited symptoms of overt S. aureus infection. Experimental infants were similar to controls with respect to feeding method, route of delivery, amount of time spent rooming-in, and average number of visitors per day. In the group of positively cultured infants, the mothers experienced longer labor, and more vaginal examinations in labor, and the number of males undergoing circumcision was higher. We concluded that routine use of cover gowns was unwarranted, and we have altered the ward policy accordingly. This also has had a positive economic effect.

Ceremonial Behavior↗
PubMed1990

Growth factor activity of endothelin on vascular smooth muscle.

Endothelin is a novel peptide secreted by endothelial cells, the vasoconstrictor effects of which appear dependent on the activation of phospholipase C. We examined in tissue culture its potential as a growth factor for vascular smooth muscle. In quiescent cultures of rat aortic smooth muscle cells, endothelin rapidly elevated levels of c-fos and c-myc mRNA. Peak effects on c-fos mRNA occurred between 15 and 30 min and were completely gone after 2 h. The elevation in c-fos mRNA was, in part, dependent on protein kinase C, since phorbol myristate acetate (PMA) also elevated c-fos mRNA and further increased c-fos mRNA expression by endothelin, but the effects were not additive. Furthermore, the endothelin-induced elevation in c-fos mRNA was attenuated but not abolished in protein kinase C-depleted cells. Maximum levels of c-myc mRNA occurred between 15 and 30 min after exposing the cells to endothelin and persisted for at least 6 h. The effects of simultaneous addition of endothelin and PMA on c-myc mRNA levels were essentially similar to those observed with c-fos mRNA. [3H]thymidine incorporation into DNA occurred 8 h after exposing the cells to endothelin. The mitogenic effect of endothelin was smaller than that observed with either fetal calf serum or epidermal growth factor and was dependent on both pertussis toxin-insensitive and -sensitive pathways. Sensitivity to the latter pathway did not appear dependent on attenuation of phospholipase C activity, since neither peak intracellular calcium concentrations nor c-fos mRNA levels were reduced in pertussis toxin-treated cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Cerebral sparganosis. Case report.

The tapeworm Spirometra mansonoides infects man worldwide, particularly in Asian countries. Rarely, the central nervous system is involved; such a case is presented here. In the total of 12 reported cases, including the case described, the worm presented clinically as a mass suspicious for neoplasm or chronic abscess cavity. Surgical removal was invariably curative in each case. Although infrequent, the possibility of tapeworm infection should be entertained in the evaluation of intracranial masses in patients who have visited exotic locales.

Adult↗
PubMed1989

Continuous aortic regurgitation in severely dysfunctional native hearts after heterotopic cardiac transplantation.

Doppler techniques were used to investigate the frequency and characteristics of aortic regurgitation (AR) in the severely deteriorated native heart after heterotopic cardiac transplantation. Ten patients were studied in whom the native left ventricular fractional shortening was less than 6%. AR was detected by Doppler in 6 patients. The AR was continuous throughout the cardiac cycle in 3 patients, continuous when present (but not occurring with every beat) in 2 patients and present throughout diastole and continued into midsystole in the remaining patient. AR was associated with abnormalities of aortic valve opening (either its complete or intermittent absence) and with poor forward flow and even reversed flow through the native heart. It is postulated that AR in this group mainly occurs as a result of abnormal locking of the aortic valve due to severely impaired left ventricular ejection. Abnormal left ventricular diastolic function and enlargement may also be contributory.

Adult↗
PubMed1989

Medical staffing in Ontario neonatal intensive care units.

Advances in technology have improved the survival rates of infants of low birth weight. Increasing service commitments together with cutbacks in Canadian training positions have caused concerns about medical staffing in neonatal intensive care units (NICUs) in Ontario. To determine whether an imbalance exists between the supply of medical personnel and the demand for health care services, in July 1985 we surveyed the medical directors, head nurses and staff physicians of nine tertiary level NICUs and the directors of five postgraduate pediatric residency programs. On the basis of current guidelines recommending an ideal neonatologist:patient ratio of 1:6 (assuming an adequate number of support personnel) most of the NICUs were understaffed. Concern about the heavy work pattern and resulting lifestyle implications has made Canadian graduates reluctant to enter this subspecialty. We propose strategies to correct staffing shortages in the context of rapidly increasing workloads resulting from a continuing cutback of pediatric residency positions and restrictions on immigration of foreign trainees.

Health Services Needs and Demand↗
PubMed1989

Factors influencing local recurrence after excision and radiotherapy for primary breast cancer.

Between November 1979 and December 1986, 263 patients were treated for primary breast cancer by local excision and radiotherapy at the City Hospital, Nottingham. Local recurrence within the treated breast occurred in 56 patients (21 per cent), in 18 (6.8 per cent) of whom it was gross and uncontrollable. An analysis of clinicopathological features shows patient age, nodal status, tumour size, presence of definitive vascular invasion, adjacent ductal carcinoma in situ and grade to be predictive of local recurrence. A Cox's multivariate analysis of these factors shows the first four to be independently significant. The factors can be combined as a prognostic index which allows identification of patients at high risk of local recurrence. On the basis of these findings we have altered our selection policy for patients suitable for breast conservation.

Adult↗
PubMed1989

Responsiveness and validity in health status measurement: a clarification.

We present data from two studies which clarify the relationship between the responsiveness and validity of instruments designed to measure health status in clinical trials. In a controlled trial of long vs short duration adjuvant chemotherapy for women with Stage II breast cancer, the Breast Cancer Chemotherapy Questionnaire (BCQ) proved valid as a measure of subjective health status and was able to distinguish long vs short arms. Well validated measures of physical and emotional function developed by the Rand Corporation were unable to distinguish between the two groups. The Eastern Co-operative Oncology Group Criteria (ECOG) distinguished the two groups, but failed criteria of clinical sensibility as a measure of subjective health status. In a study of patients with Crohn's disease and ulcerative colitis, the Inflammatory Bowel Disease Questionnaire (IBDQ) showed small intrasubject variability over time. Gobal ratings of change showed moderate to high correlations with changes in IBDQ score, and patients who reported overall improvement or deterioration showed large changes in IBDQ score. Each of these findings support, in different ways, the reproducibility, validity, and responsiveness of the questionnaire. While the same data can at times bear on both validity and responsiveness, when assessing evaluative instruments it is useful to make a conceptual distinction between the two.

Breast Neoplasms↗
PubMed1989

Timed oocyte collection in an assisted conception programme using GnRH analogue.

Three-hundred-and-twenty-five patients on an assisted conception programme underwent 378 cycles of oocyte retrieval (OPU) following ovarian stimulation using a GnRH analogue and human menopausal gonadotrophins (HMG), a regimen which allows programmed cycles and delayed oocyte retrieval. Eighteen cycles were excluded (failed OPU in three and failure of fertilization in 15). In 360 cycles, patients completed their treatment with either in-vitro fertilization/embryo transfer (IVF/ET) (116) or gamete intra-Fallopian transfer (GIFT) (244), of which 241 took place at the normal time and 119 were delayed for 24 h or more to avoid weekend operating. The overall pregnancy rate per OPU was 29.5%, with the IVF group being 24.1% and the GIFT group being 32.8%. In the group of patients in whom OPU was delayed, the pregnancy rate was significantly higher in each sub-group than in the corresponding non-delayed sub-group (overall, 37.0 versus 25.7%; IVF/ET, 38.5 versus 16.9%; GIFT, 36.3 versus 31.1%). There was a significantly higher number of oocytes collected, gametes/embryos transferred in the group whose OPU had been delayed. In patients receiving GnRH analogue and HMG for ovarian stimulation, delaying oocyte retrieval is not harmful, may result in an improved outcome and allows OPU to be performed on routine operating lists. This facility, together with the improved pregnancy rates associated with this protocol of ovarian stimulation should improve the cost-effectiveness of assisted conception programmes.

Adult↗
PubMed1989

Limitations of patient triggered ventilation in neonates.

The practicality of long term patient triggered ventilation using airflow changes was assessed in 22 infants with a median gestational age of 29 weeks (range 25-33 weeks). Inflation time during patient triggered ventilation was limited to 0.4 seconds or less. Initially it was associated with improvements in oxygenation in most infants. Patient triggered ventilation was maintained till final extubation in 13 of the infants without complications. Only one infant developed a pneumothorax, but in the remaining eight infants (who tended to be less mature (p less than 0.01) it had to be discontinued after only a few hours. Predictors of failure of patient triggered ventilation at one hour were both a lack of improvement in oxygenation, and a relatively slow triggering rate that was related to gestational age. We conclude that long term patient triggered ventilation is practical for preterm neonates, but only for those more mature than 28 weeks' gestational age.

Evaluation Studies as Topic↗
PubMed1989

Diastolic function after cardiac and heart-lung transplantation.

The mechanical efficiency of left ventricular contraction and relaxation, the asynchrony of the onset of left ventricular relaxation, the time constant of left ventricular isovolumic pressure decay, and left ventricular chamber and myocardial stiffness were analysed in 32 patients after cardiac (24) and heart-lung transplantation (8). After cardiac transplantation left ventricular myocardial stiffness was increased and a mild degree of incoordinate contraction and relaxation was seen. In contrast, after heart-lung transplantation diastolic function was almost normal. Impairment of passive diastolic properties was significantly related to the ischaemic time of the donor heart and the donor's age. The index of left ventricular asynchrony was related to the ischaemic time and the recipient's age. The interval between transplantation and study did not influence the number of rejection episodes. This study confirms the presence of diastolic dysfunction after cardiac transplantation. Impairment of diastolic function seems to be related to the ischaemic time of the donor heart and to a mismatch between the size of the donor heart and the recipient's needs.

Adolescent↗
PubMed1989

Conn's syndrome due to an ectopic adrenal adenoma.

A 31 year old woman presented with resistant hypertension. Investigations revealed that she had Conn's syndrome. Computed tomography showed both adrenals to be normal but an ectopic adenoma was identified posterior to the stomach. Surgical excision of the tumor confirmed benign aldosteronoma and cured her hypertension. We believe this to be the first report of Conn's syndrome caused by an ectopic adrenal adenoma.

Adenoma↗
PubMed1989

Temporal lobectomy: an increasingly viable option for seizure patients.

Over the past ten years, the treatment options available to people with epilepsy have changed drastically, resulting in new concepts, treatment methods and philosophies. Complex partial seizures (temporal lobe or psychomotor) account for one third of all chronic seizure disorders. Following temporal lobectomy, the majority of these patients no longer requires medication. The neuroscience nurse must understand the selection criteria, diagnostic tests and perioperative course in order to teach and support these individuals and their families.

Adult↗
PubMed1989

A new measure of health status for clinical trials in inflammatory bowel disease.

We have developed a measure of subjective health status (quality of life) for patients with inflammatory bowel disease (IBD). Ninety-seven patients with IBD described problems they had experienced as a result of the disease; the 32 most frequent and important items were included in the Inflammatory Bowel Disease Questionnaire (IBDQ). Sixty-one IBD patients were evaluated twice. One month separated the evaluations, at which disease activity indices, the IBDQ, and a number of other questionnaires were administered. Reproducibility studies in 19 stable patients showed improvement in scores, but also a small within-person standard deviation. Responsiveness studies revealed large changes in scores in patients who had improved or deteriorated and suggested that the IBDQ was more responsive than a general health status measure. Responsiveness appeared greater in patients with ulcerative colitis than in those with Crohn's disease. Predicted and observed correlations between changes in IBDQ score and changes in other measures were similar. We conclude that although further testing is required, particularly in examining the relation between changes in the IBDQ and changes in the activity of Crohn's disease, the IBDQ shows promise as a measure of health status for clinical trials in IBD.

Attitude to Health↗