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E Wilson

Publications and source records attributed to E Wilson.

At least 55 records · Page 3Linked to original sources
PubMed2000

Myosin light chain kinase transference induces myosin light chain activation and endothelial hyperpermeability.

The actomyosin complex is the major cytoskeletal component that controls cell contraction. In this study, we investigated the effects of actomyosin interaction on endothelial barrier function and gap formation. Activated myosin light chain kinase (MLCK) protein was transferred into coronary venular endothelial cell (CVEC) monolayers. Uptake of the activated protein resulted in a significant shift in myosin light chain (MLC) from an unphosphorylated to a diphosphorylated form. In addition, MLCK induced a hyperpermeability response of the monolayer as measured by albumin transendothelial flux. Microscopic examination of MLCK-treated CVECs revealed widespread gap formation in the monolayer, loss of peripheral beta-catenin, and increases in actin stress fibers. Inhibition of all of the above responses by a specific MLCK inhibitor suggests they are the direct result of exogenously added MLCK. These data suggest that activation of MLCK in CVECs causes phosphorylation of MLC and contraction of CVECs, resulting in gap formation and concomitant increases in permeability. This study uses a novel technique to measure the effects of an activated kinase on both its substrate and cellular morphology and function through direct transference into endothelial cells.

Actins↗
PubMed1999

Lifestyle modifications to prevent and control hypertension. 1. Methods and an overview of the Canadian recommendations. Canadian Hypertension Society, Canadian Coalition for High Blood Pressure Prevention and Control, Laboratory Centre for Disease Control at Health Canada, Heart and Stroke Foundation of Canada.

OBJECTIVE: To provide updated, evidence-based recommendations for health care professionals on lifestyle changes to prevent and control hypertension in otherwise healthy adults (except pregnant women). OPTIONS: For people at risk for hypertension, there are a number of lifestyle options that may avert the condition--maintaining a healthy body weight, moderating consumption of alcohol, exercising, reducing sodium intake, altering intake of calcium, magnesium and potassium, and reducing stress. Following these options will maintain or reduce the risk of hypertension. For people who already have hypertension, the options for controlling the condition are lifestyle modification, antihypertensive medications or a combination of these options; with no treatment, these people remain at risk for the complications of hypertension. OUTCOMES: The health outcomes considered were changes in blood pressure and in morbidity and mortality rates. Because of insufficient evidence, no economic outcomes were considered. EVIDENCE: A MEDLINE search was conducted for the period January 1996 to September 1996 for each of the interventions studied. Reference lists were scanned, experts were polled, and the personal files of the authors were used to identify other studies. All relevant articles were reviewed, classified according to study design and graded according to level of evidence. VALUES: A high value was placed on the avoidance of cardiovascular morbidity and premature death caused by untreated hypertension. BENEFITS, HARMS AND COSTS: Lifestyle modification by means of weight loss (or maintenance of healthy body weight), regular exercise and low alcohol consumption will reduce the blood pressure of appropriately selected normotensive and hypertensive people. Sodium restriction and stress management will reduce the blood pressure of appropriately selected hypertensive patients. The side effects of these therapies are few, and the indirect benefits are well known. There are certainly costs associated with lifestyle modification, but they were not measured in the studies reviewed. Supplementing the diet with potassium, calcium and magnesium has not been associated with a clinically important reduction in blood pressure in people consuming a healthy diet. RECOMMENDATIONS: (1) It is recommended that health care professionals determine the body mass index (weight in kilograms/[height in metres]2) and alcohol consumption of all adult patients and assess sodium consumption and stress levels in all hypertensive patients. (2) To reduce blood pressure in the population at large, it is recommended that Canadians attain and maintain a healthy body mass index. For those who choose to drink alcohol intake should be limited to 2 or fewer standard drinks per day (maximum of 14/week for men and 9/week for women). Adults should exercise regularly. (3) To reduce blood pressure in hypertensive patients, individualized therapy is recommended. This therapy should emphasize weight loss for overweight patients, abstinence from or moderation in alcohol intake, regular exercise, restriction of sodium intake and, in appropriate circumstances, individualized cognitive behaviour modification to reduce the negative effects of stress. VALIDATION: The recommendations were reviewed by all of the sponsoring organizations and by participants in a satellite symposium of the fourth international Conference on Preventive Cardiology. They are similar to those of the World Hypertension League and the Joint National committee, with the exception of the recommendations on stress management, which are based on new information. They have not been clinically tested. SPONSORS: The Canadian Hypertension Society, the Canadian Coalition for High Blood Pressure Prevention and Control, the Laboratory Centre for Disease Control at health Canada, and the Heart and Stroke Foundation of Canada.

Adult↗
PubMed1999

A circulating bovine gamma delta T cell subset, which is found in large numbers in the spleen, accumulates inefficiently in an artificial site of inflammation: correlation with lack of expression of E-selectin ligands and L-selectin.

Tissue-specific localization of TCR-defined subsets of gamma delta T cells has been widely reported; however, the mechanisms responsible for this phenomenon are poorly understood. We describe a bovine gamma delta T cell TCR-associated subset that preferentially localizes in the spleen. This subset was characterized by coexpression of CD8, and was found to lack surface expression of E-selectin ligands, GR Ag ligands, as well as low expression of L-selectin. The CD8-positive gamma delta T cell subset did not accumulate at sites of inflammation as efficiently as CD8-negative gamma delta T cells that, in contrast, express E-selectin and GR ligands and high levels of L-selectin. This is the first demonstration of a gamma delta T cell subset, which exhibits a defined tissue tropism, having a unique adhesion molecule expression profile. These results demonstrate that in some cases tissue-specific accumulation of gamma delta T cell subsets can be predicted by expression, or lack of expression, of defined homing molecules.

Animals↗
PubMed1999

Rapid induction and translocation of Egr-1 in response to mechanical strain in vascular smooth muscle cells.

The effect of mechanical strain on transcription and expression of the immediate-early genes, early growth response gene-1 (Egr-1), c-jun, and c-fos, was investigated in neonatal rat aortic vascular smooth muscle (VSM) cells. Cells grown on silicone elastomer plates were subjected to cyclic mechanical strain (1 Hz) at various durations and magnitudes. Egr-1 mRNA increased rapidly in response to cyclic strain, reached a maximum of 10-fold after 30 minutes, and returned to baseline after 4 hours. c-jun exhibited a similar pattern, whereas c-fos mRNA expression was unaffected by strain. Cycloheximide prolonged the increase in Egr-1 and c-jun mRNA and caused superinduction of both. The threshold level of continuous cyclic strain needed to induce expression was 5% for Egr-1 and c-jun. Even a single cycle of mechanical strain that lasted 1 second was sufficient to induce Egr-1 and c-jun mRNA. Strain also increased expression of a transiently transfected Egr-1 promoter-reporter construct. The effect of varying extracellular matrices on strain-induced Egr-1 and c-jun mRNA was examined. In contrast to collagen type 1- and pronectin-coated plates, strain did not significantly alter expression of Egr-1 and c-jun was less induced on laminin-coated plates. On collagen type 1, strain increased Egr-1 protein levels by 2.1-fold at 60 minutes. Immunofluorescence microscopy revealed translocation of Egr-1 to the nucleus in response to strain. These observations indicate that Egr-1 expression and translocation are sensitive to mechanical perturbation of the cell. c-jun is also induced by strain, but c-fos is not. The signal for this induction may involve specific cell-matrix interactions.

Animals↗
PubMed1999

Intratracheal administration of interleukin 12 plasmid-cationic lipid complexes inhibits murine lung metastases.

Administration of plasmid/lipid complexes to the lung airways for the treatment of metastatic pulmonary diseases represents a new strategy of gene therapy. In this study we present evidence that intratracheal administration of a plasmid encoding murine IL-12 complexed with N-[1-(2,3-dioleyloxy)propyl)-N,N,N-trimethylammonium chloride:cholesterol inhibits the growth of lung metastases, using a renal cell carcinoma model. Instillation of pIL-12/lipid complexes resulted in expression of biologically active IL-12 (170-240 pg/ml) and IFN-gamma (100-190 pg/ml) in the bronchoalveolar lavage fluid. A significantly reduced number of lung metastases (26+/-24) was observed in mice instilled with IL-12/lipid complexes 24 hr after tumor challenge, whereas more than 250 metastatic foci were counted in lungs of untreated mice. Moreover, IL-12/lipid inhibited the growth of 3-day-old established metastases when compared with empty plasmid/lipid or IL-12 plasmid in saline. Mice receiving IL-12 gene therapy survived significantly longer (median survival of 43 days) than untreated mice (median survival of 31 days) or mice treated with control plasmid/lipid complexes (median survival of 35 days). These data demonstrate that a nonviral IL-12 gene therapy employing synthetic cationic lipids as a delivery system can be used to inhibit the development of lung metastases. Thus, this method provides support for the use of IL-12/lipid complexes to control the growth of pulmonary metastases and represents a potentially safer alternative to IL-12 protein immunotherapy.

Animals↗
PubMed1999

A case of discordant related abnormal karyotypes from chorionic villi and amniocytes.

A case of three discordant cell lines in prenatal diagnosis is described, of which two were abnormal related structural abnormalities of chromosome 11. One of the abnormal cell lines was seen in all metaphases examined from direct preparations of chorionic villi, the cultured preparations showing an apparently normal male karyotype; the other abnormal cell line was seen in conjunction with a normal cell line in cultured amniocytes. Prenatal diagnosis offered solely on chorionic villus sampling would have yielded a mistakenly normal result on the basis of established criteria for distinguishing true mosaicism from confined placental mosaicism.

Adult↗
PubMed1999

An analysis of first-time enquirers to the CancerBACUP information service: variations with cancer site, demographic status and geographical location.

A retrospective comparison of cancer incidence data and, where relevant, population data with 16,955 first-time users (patients, relatives and friends) of a national cancer information service (CancerBACUP) during the period April 1995 to March 1996 is presented. The number of events observed was compared with the number of events expected, were the national rates of cancer incidence and population demographics apply. Standardized incidence ratios (SIRs) (observed - expected ratios) were used to indicate any differences. Statistically significant differences (P < 0.001) in the observed and expected sex, age and primary site distribution of patients enquired about were found. Statistically significant differences (P < 0.001) were also identified for the age, employment status, socioeconomic class and geographical location of first-time enquirers (patients, relatives and friends). Enquiries about brain, testis and breast cancers and non-Hodgkin's lymphoma (NHL) were substantially higher than expected; enquiries about bladder, lung, stomach and colorectal cancers were much lower than expected. As the service is provided via a freephone number, it is available to all, and users might be expected to be randomly distributed across the variables listed. The underlying reasons for the differences identified need to be investigated, and the role of information in the care of cancer patients should be formally evaluated.

Adult↗
PubMed1999

Pain memory.

Explore the source record for details and available documents.

Accidental Falls↗
PubMed1999

Matrix-dependent gene expression of egr-1 and PDGF A regulate angiotensin II-induced proliferation in human vascular smooth muscle cells.

We have previously shown, in a neonatal rat cell line, that angiotensin II (Ang II)-induced proliferation in vascular smooth muscle cells is extracellular matrix (ECM) dependent. We hypothesized that such an effect might be mediated via differences in Ang II-induced increases in the transcriptional factor early growth response-1 (Egr-1) gene and, consequently, in platelet-derived growth factor (PDGF). Cultured human newborn aortic smooth muscle cells were studied on 4 different surfaces: (1) plastic, (2) laminin, (3) collagen, and (4) fibronectin. Ang II-induced increases in DNA synthesis were significantly greater on collagen (2.0+/-0.3-fold) and fibronectin (1.9+/-0.3-fold) than on laminin (1.0+/-0.2-fold) or plastic (1.4+/-0.2-fold). As with DNA synthesis, at 48 and 72 hours, Ang II-induced increases in cell numbers occurred only in cells grown on collagen and fibronectin culture plates and were blocked by an antagonist to the angiotensin type 1 (losartan, 10 micromol/L) but not the angiotensin type 2 (PD 123319, 10 micromol/L) receptor. Anti-PDGF AA antibody (6 microg/mL) blocked the increase in DNA synthesis by 60% to 64% in cells on collagen or fibronectin cultures but not on plastic cultures. When PDGF-AA (10 ng/mL) and Ang II were added together, DNA synthesis increased 2-fold and did not differ on the various ECM proteins. Increases in PDGF A-chain mRNA were observed only in cells grown on collagen (3.21+/-0.65-fold) and fibronectin (2.86+/-0.49-fold) plates 2 to 8 hours after the addition of Ang II and were blocked by losartan but not PD 123319. Expression of Egr-1, an early growth response gene, increased at 15 minutes, peaked at 30 minutes, and returned to normal after 2 hours with Ang II treatment. Ang II-induced increases in Egr-1 mRNA were greater on collagen (4. 82+/-0.66-fold at maximum) and fibronectin (4.01+/-0.56-fold) than on laminin (2.74+/-0.45-fold) or plastic (2.53+/-0.40-fold) and were blocked by losartan but not PD 123319. Thus, in human vascular smooth muscle cells in culture, Ang II-induced proliferation is mediated via the angiotensin type 1 receptor, dependent on ECM proteins, and regulated by differential gene expression of Egr-1 and PDGF-1.

Angiotensin II↗
PubMed1999

Scrotal (Bianchi) approach to patent processus vaginalis in children.

Ligation of an indirect inguinal hernia or communicating hydrocele is the most frequent operation performed on children by pediatric surgeons and urologists. We describe our experience with the scrotal (Bianchi) approach to these problems rather than the traditional inguinal approach.

Adolescent↗
PubMed1998

Preferential tissue localization of bovine gamma delta T cell subsets defined by anti-T cell receptor for antigen antibodies.

Clonal and oligoclonal populations of gammadelta T cells, with respect to the expression of T cell receptors for antigen (Tcr), have been shown to localize in normal and inflamed tissues. The mechanisms responsible for the tissue-selective accumulation of these subsets are still not known. gammadelta T cells are the predominant T cell subset in newborn calves, making this animal a useful model to study these cells. However, molecular markers defining tissue-specific bovine ydelta T cell subsets are only now being developed. In this report, we describe three new anti-bovine gammadelta Tcr mAbs: GD3.8, GD197 and GD3.1, which provide useful tools to study these cells. GD3.8 recognized virtually all gammadelta T cells in the blood; whereas GD3.1 and GD197 recognized mutually exclusive as well as overlapping subsets. Using these three mAbs, four separate subsets of gammadelta T cells were defined: subset 1 (GD3.8+, GD3.1+, GD197-); subset 2 (GD3.8+, GD3.1-, GD197+); subset 3 (GD3.8+, GD3.1+, GD197+); and subset 4 (GD3.8+, GD3.1-, GD197-). Subset 4 constituted a minor population in the blood; however, it predominated in the spleen and, in some cases, represented a 300% increase over blood levels. The percentage of GD3.1-positive gammadelta T cells was found to be increased in experimentally inflamed lymph nodes, suggesting that subset 1 cells may be preferentially retained in or recruited to sites of inflammation. Some subset 4 cells also exhibited a decreased ability to respond to PHA. These studies demonstrate that bovine gammadelta T cell, Tcr-defined subsets, exhibit unique accumulation and activation characteristics that may provide clues to their function and regulation.

Animals↗