Search PubMed⌕ Search

Biomedical subjects

J Scott

Publications and source records attributed to J Scott.

At least 757 records · Page 42Linked to original sources

Insulin-like growth factor-II gene expression in Wilms' tumour and embryonic tissues.

Wilms' tumour (nephroblastoma) is an embryonal neoplasm occurring in hereditary and spontaneous forms. Both types show rearrangements of the short arm of chromosome 11. The germ line of children with the rare inherited triad of aniridia, genito-urinary abnormality and mental retardation carry a chromosome 11 that has a deletion in its short arm (band 11p13) and these children are at increased risk of developing Wilms' tumour. Neonates with the Beckwith-Wiedemann syndrome, in which there may be duplication of the 11p13-11p15 region, are similarly predisposed. In the spontaneous form of the tumour a deletion of the 11p14 band in tumour cells, but not in normal cells, has been reported, and the development of homozygosity for recessive mutations in the 11p region is implicated in the aetiology of Wilms' tumour. In view of these chromosomal rearrangements and because Wilms' tumour is histologically indistinguishable from the early stages of kidney development, we have now examined the expression of genes localized to 11p in Wilms' tumour and human embryonic tissue. In 12 sporadic tumours examined, the expression of the gene coding for insulin-like growth factor-II (IGF-II), localized to the 11p15 region, was markedly increased relative to adult tissues, but was comparable to the level of expression in several fetal tissues including kidney, liver, adrenals and striated muscle. This may reflect the stage of tumour differentiation, but could also contribute to the malignant process, as IGF-II is an embryonal mitogen.

Female↗

Critical analysis of intravenous immunoglobulin therapy for recurrent miscarriage.

Critical analysis of intravenous immunoglobulin therapy for recurrent miscarriage An alloimmune abnormality is believed to be the cause of recurrent miscarriage in couples in whom no other cause can be identified. Because of its immunosuppressive properties, intravenous immunoglobulin (IVIG) is used as a treatment for this disorder. The purpose of this study was to determine whether IVIG improves the chance of successful pregnancy in women with recurrent miscarriage by using individual patient data from efficacy trials. Detailed information on each patient enrolled in these trials was obtained to evaluate the efficacy of IVIG and investigate the effect of clinical variability on pregnancy outcome. Data from 125 patients in the IVIG group and 115 patients in the placebo group were available for analysis. Although the number of previous miscarriages and female age were both negative prognostic factors for successful outcome, there was no significant improvement in successful pregnancy or live birth rate with IVIG. Subgroup analyses indicated that timing of IVIG administration may be important. The results of the present study highlight the importance of stratification for known confounders, so that the role of IVIG can be evaluated in more detail. The collective evidence thus far indicates that IVIG does not have a therapeutic effect that is clinically meaningful.

Abortion, Habitual↗

Employee motivation: new perspectives of the age-old challenge of work motivation.

In this qualitative study, the 1950s-1970s work of Frederick Herzberg, the father of work motivational research, was compared, and contrasted with current data study about management effectiveness to explore how employee motivation may have changed. Staff members and managers (N = 38), primarily from healthcare settings, but also from academic, public, and private sector businesses were interviewed. Interpersonal relations now ranks first as a motivating factor in this study. Recognition, the work itself, and responsibility are still ranked as critical motivating factors. These are important to understand as work is redesigned. Supporting positive interpersonal relations among subordinates, supervisors, and peers can be viewed as an effective management strategy to facilitate employee motivation. For employees, developing positive interpersonal relations with co-workers can enhance individual motivation and may improve job satisfaction.

Adult↗

Empirical scaling of the stages of cognitive decline in senile dementia.

A 30-item questionnaire concerned with signs and symptoms of cognitive decline was completed by a relative or caregiver for each of 115 elderly patients seen in the gerontology outpatient clinic of our institution. Twelve different preliminary scale values were calculated to locate each of the 30 clinical manifestations along a continuum of increasing severity. Principal components analysis was then used to combine the 12 preliminary indices into a single composite scale that more reliably represents distances between the 30 clinical manifestations. The scale scores for the clinical manifestations were observed to cluster into relatively discrete groups, suggesting naturally occurring stages or phases. Objective cluster analysis methods further suggested the presence of distinct thresholds for occurrence of new impairments along the cognitive decline continuum. Utility of the empirically derived scale values in staging the course of primary degenerative dementia is suggested.

Aged↗

Evaluation of a partnership model of care delivery involving registered nurses and unlicensed assistive personnel.

The employment of unlicensed personnel in Canadian acute care hospitals has been undertaken without clear evidence of outcomes for patients, caregivers, and hospital organizations. This quasi-experimental evaluation study was completed in a metropolitan Toronto acute care hospital to examine the effects of a new nursing care delivery system which included unlicensed assistive personnel. Most of the expected benefits of the newly implemented nursing care delivery system did not materialize leading to the conclusion that the employment of unlicensed assistive personnel in acute care hospital systems may not offer additional benefits for patients, caregivers, or hospital organizations. The processes and results of this study provide useful information for nurse administrators who are seeking effective and innovative care delivery systems that are designed to optimize patient, caregiver, and hospital outcomes.

Attitude of Health Personnel↗

Nutritional awareness of critically ill surgical high-dependency patients.

It has been recognized that malnutrition in hospital is a serious problem that may go undetected. There is growing evidence that early nutritional support in high-risk patients helps reduce postoperative complications; however, malnutrition is often diagnosed only once it is well established. This study showed that, both retrospectively and prospectively; there were no formal nutritional assessments of patients in a high-dependency unit (HDU), that time to feeding was generally within the recommended 5-7 day postoperative period, and that the most common form of supplementary feeding was total parenteral nutrition (TPN). Prospectively, the choice of supplementary feeding was dependent on the type of surgery and the individual patient's condition. Since this study was completed, a dietician has been allocated to the HDU and carries out formal nutritional assessments on a daily basis. Further research is required to assess the impact of the dietician on patient nutrition.

Activities of Daily Living↗

Role of the ras-MAPK signaling pathway in the DNA methyltransferase response to DNA hypomethylation.

Our group reported that inhibiting DNA methylation in human T cells increases DNA methyltransferase expression and activity, and suggested that this may represent a response to DNA hypomethylation. The increase correlates with increases in Ha-ras and c-jun, suggesting that increased signaling through the ras-MAPK pathway, due to overexpression of some elements, may be responsible. However, whether human DNA MTase is regulated by the ras-MAPK pathway, and whether overexpression of elements in this pathway will increase DNA MTase, is unknown. We report that treating cells with a DNA methylation inhibitor increases transcription regulated by a putative DNA MTase promoter, and that this increase requires AP-1 sites. Additional studies demonstrate that overexpression of an unmutated Ha-ras causes an increase in DNA MTase, and that human T cell DNA MTase can be decreased by inhibiting signaling through the ras-MAPK pathway. Together, these studies suggest that human T cell DNA MTase is regulated through the ras-MAPK pathway, and that overexpression of Ha-ras is sufficient to increase DNA MTase expression. These results thus provide a mechanism for the increase in DNA MTase observed after inducing DNA hypomethylation, a response which may have relevance to some disease states.

Animals↗

IgG4 antibody response in allergic patients during immunotherapy.

The duration of the antigenic stimulation is a critical issue, but probably more important are the relevance and the purity of the allergen(s). A significant level of IgG4 antibodies has been detected as early as 3 months after initiating immunotherapy with hymenoptera venoms; in our patients, grass pollens, being more "pure", were able to induce an IgG4 response earlier than house dust mites or molds. The cumulative dose of allergen is also an important issue.

Allergens↗

emm typing and validation of provisional M types for group A streptococci.

This report discusses the following issues related to typing of group A streptococci (GAS): The development and use of the 5' emm variable region sequencing (emm typing) in relation to the existing serologic typing system; the designation of emm types in relation to M types; a system for validation of new emm types; criteria for validation of provisional M types to new M-types; a list of reference type cultures for each of the M-type or emm-type strains of GAS; the results of the first culture exchange program for a quality control testing system among the national and World Health Organization collaborating centers for streptococci; and dissemination of new approaches to typing of GAS to the international streptococcal community.

Antigens, Bacterial↗

The use of exercise technetium-99m 2-methoxy-isobutyl-isonitrile (99mTc-Sestamibi) perfusion scanning in the detection of acute rejection after cardiac transplantation.

Acute cardiac rejection remains an important cause of death during the first year following cardiac transplantation. Right ventricular biopsies at regular intervals are the main method of detecting rejection, although it is invasive. Unfortunately, non-invasive methods of detecting rejection have not proved reliable enough to replace cardiac biopsies. We assessed the usefulness of technetium-99m 2-methoxy-isobutyl-isonitrile (99mTc-Sestamibi) perfusion scanning in detecting acute rejection in 12 human orthotopic cardiac transplant recipients. Rest and exercise studies and right ventricular biopsies were performed on two occasions. Isotopic evidence of rejection was defined as a perfusion abnormality on either the resting or exercise studies. 99mTc-Sestamibi studies successfully identified acute rejection in 8 of 11 rejection episodes (p less than 0.04). The calculated sensitivity and specificity of 99mTc-Sestamibi scanning were both 72%. Perfusion scanning with 99mTc-Sestamibi may be useful in the diagnosis of acute rejection in cardiac transplant recipients.

Adult↗

A comparison of UW cold storage solution and St. Thomas' solution II: a 31P NMR and functional study of isolated porcine hearts.

Although University of Wisconsin cold storage solution provides excellent preservation for the pancreas, the kidney, and the liver after extended cold ischemic storage, its ability to preserve the heart for extended cold storage periods is not yet proved. This study was carried out to evaluate the effect of University of Wisconsin solution on heart preservation and to compare it to modified St. Thomas' solution II with respect to the capacity to preserve high-energy phosphates and contractile function in pig hearts. Hearts were arrested with either University of Wisconsin cold storage solution or St. Thomas' solution II (10 ml/kg) and kept ischemic at 12 degrees C or 4 degrees C for 8 hours. Functional recovery after the preservation period was assessed by means of ventricular function curves of the isovolumically contracting Langendorff model perfused with modified Krebs-Henseleit solution. Phosphorus 31 nuclear magnetic resonance spectroscopy was used to monitor high-energy phosphates and intracellular pH during preservation and reperfusion. At 12 degrees C, hearts arrested and preserved with University of Wisconsin solution showed a rapid decrease in phosphocreatine and adenosine triphosphate. With St. Thomas' solution, phosphocreatine and adenosine triphosphate decreased slowly. Functional recovery was poorer with University of Wisconsin solution than with St. Thomas' solution. Hearts preserved at 4 degrees C with either solution showed no significant differences in high-energy phosphate content and functional recovery. Rigorous control of the low temperature (4 degrees C) is necessary when University of Wisconsin solution is used for heart preservation.

Adenosine↗

Histologic prognostic indicators for the lung allografts of heart-lung transplants.

The histologic changes in transbronchial lung biopsy specimens of heart-lung transplant patients were graded during episodes of acute rejection and when patients were well. Infection was strictly excluded from all episodes studied. Grade of severity of rejection was determined by the magnitude and extent of the inflammatory infiltrate. Biopsy specimens, obtained 1 year after the initial biopsies, were examined for histologic evidence of airway submucosal fibrosis, and each patient's clinical status at this time was recorded. The biopsy material from 22 long-term survivors was studied. On 16 occasions the specimens showed no evidence of rejection (grade 0). Twelve of these sets of specimens were from clinically well patients, and four were from the patients who had clinical evidence of rejection. The other six sets of specimens, from clinically well patients, showed evidence of rejection: three grade 1 and three grade 2. One year later, the clinically well patients had normal biopsy histology without fibrosis and normal lung function. Bronchiolitis obliterans had not developed in any patient. There were 27 episodes of rejection in the 22 patients, of which 23 were confirmed histologically. Eleven sets of specimens had grade 1 acute rejection, eight grade 2, and four grade 3. Three of these patients died, and bronchiolitis obliterans was confirmed at necropsy. Lung fibrosis was more common in specimens taken after 1 year, and lung function was depressed in these patients. The histologic grading of transbronchial lung biopsy material, although still in the early stages of development, provides some predictive value to the long-term outcome of the lung transplant patient, in development of both bronchiolitis obliterans and lesser fibrotic changes.

Biopsy↗