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S Reid

Publications and source records attributed to S Reid.

At least 73 records · Page 4Linked to original sources
PubMed1999

SDF-1 suppresses cytokine-induced adhesion of human haemopoietic progenitor cells to immobilized fibronectin.

The process of haemopoietic cell homing to the microenvironment includes migration and adhesion. SDF-1 is a C-X-C chemokine that acts as a chemoattractant for haemopoietic progenitors. Adhesion of haemopoietic progenitors to immobilized fibronectin is up-regulated by stimulation with cytokines. We assessed the effects of SDF-1 on cytokine-induced adhesion of progenitor cells to fibronectin. In factor-dependent human MO7e cells and primary CD34+ cord blood cells, treatment with SDF-1 dose-dependently suppressed cytokine-induced adhesion. Pretreatment with pertussis toxin reversed adhesion-inhibition, suggesting that activation of G-coupled proteins are involved in the intracellular signalling of this process. These data suggest that SDF-1 not only acts as a chemoattractant but also participates in modulating adhesiveness of haemopoietic progenitors to extracellular matrix components.

Cell Adhesion↗
PubMed1999

Mastectomy or lumpectomy? Helping women make informed choices.

PURPOSE: To develop an instrument to help clinicians inform their patients about surgical treatment options for the treatment of breast cancer and to evaluate the impact of the instrument on the clinical encounter. METHODS: We developed an instrument, called the Decision Board, to present information regarding the benefits and risks of breast-conserving therapy (lumpectomy plus radiation therapy) and mastectomy to women with early-stage breast cancer to enable them to express a preference for the type of surgery. Seven surgeons from different communities in Ontario administered the instrument to women with newly diagnosed clinical stage I or II breast cancer over an 18-month period. Patients and surgeons were interviewed regarding acceptability of the instrument. The rates of breast-conserving surgery performed by surgeons before and after the introduction of the instrument were compared. RESULTS: The Decision Board was administered to 175 patients; 98% reported that the Decision Board was easy to understand, and 81% indicated that it helped them make a decision. The average score on a true/false test of comprehension was 11.8 of 14 (84%) (range, 6 to 14). Surgeons found the Decision Board to be helpful in presenting information to patients in 91% of consultations. The rate of breast-conserving surgery decreased when the Decision Board was introduced (88% v 73%, P =.001) CONCLUSION: The Decision Board is a simple method to improve communication and facilitate shared decision making. It was well accepted by patients and surgeons and easily applied in the community.

Adult↗
PubMed1999

Health-related correlates of gambling on the British National Lottery.

The National Lottery has been estimated as being played by 65% of the adult British population. This study investigated whether higher average weekly spending on the Lottery is associated with various health-related variables. Results from a survey of 482 British adults (mean age = 33.3 yr.), consisting of 107 students and 375 people in employment, indicated that those who spent more on the Lottery had significantly poorer social functioning (Social Functioning scale of the SF-36 Health Survey), higher weekly alcohol and cigarette consumption, and lower frequency of social support (Emotional and Social Interaction scales of the Medical Outcomes Study Social Support Survey). By contrast, higher lottery spending was not associated with poorer general mental health (General Health Questionnaire). Manual workers spent over twice the weekly amount on the Lottery compared to nonmanual workers. Consumption of alcohol and cigarettes was lower than recently published UK norms. Results suggest that higher Lottery spending among the general adult population possibly may be linked specifically to restrictions in social activity. The association of Lottery spending with alcohol and cigarette use among a sample whose consumption was relatively low appears to require explanation within psychological theories of addiction. The over-all pattern of results is discussed in relation both to addiction theory and to the Lottery's widespread appeal and availability.

Adult↗
PubMed1999

The effects of GM-CSF, steel factor and MIP-1alpha on the expression and activation of Cdc25A phosphatase in Mo7e cells.

Active cyclin-dependent kinases (CDKs) are required for progression through the G1 phase of the cell cycle and entry into S phase. Activity of G1 CDKs is controlled by mechanisms including phosphorylation of Thr14 and Tyr15 residues. Removal of inhibitory phosphates on these amino acid residues is required for G1 CDK activation, and is mediated by the Cdc25A phosphatase. Regulation of active Cdc25A phosphatase levels may be important for the proliferation of hematopoietic progenitor cells, effects assessed in the human growth-factor-dependent cell line Mo7e. Constitutive Cdc25A protein levels were enhanced with granulocyte-macrophage colony-stimulating factor (GM-CSF) plus steel factor (SF). Cdc25A is thought to exert its activity in the nucleus, and nuclear protein levels of Cdc25A were also enhanced with GM-CSF and SF. GM-CSF plus SF promote synergistic growth of Mo7e cells. Pretreatment with macrophage inflammatory protein (MIP-1alpha) inhibited GM-CSF- plus SF-induced growth and upregulation of Cdc25A protein levels. Stimulation with GM-CSF and SF also rapidly increased Cdc25A phosphatase activity, an effect suppressed by MIP-1alpha. A concomitant inhibition of increased CDK4 kinase activity correlated with increased phosphotyrosine levels on CDK4 when cells were pretreated with MIP-1alpha prior to GM-CSF and SF. These data suggest that Cdc25A expression and activity are regulated during proliferation of Mo7e cells.

Blotting, Western↗
PubMed1999

Differential in vitro maturation of hematopoietic stem cells from wild-type and immunoglobulin transgenic mice.

During B-cell lymphopoiesis, hematopoietic stem cells commit to the B-cell lineage as monitored by the expression of phenotypic cell surface antigens and the production of immunoglobulin chains. Two cytokines, interleukin-7 (IL-7) and Flt-3 ligand (FL), appear to act in conjunction to drive this development process. Using an in vitro, stroma-free culture system and these cytokines, the commitment of murine Sca+ Lin- bone marrow cells to the B-cell lineage was examined with stem cells from immunoglobulin (Ig) transgenic and wild-type mice. After 12 days of culture in IL-7 and FL, stem cells from wild-type animals had matured to express surface B220, CD19, CD43, BP-1 and heat-stable antigen (HSA). These cells lacked detectable intracellular mu chains while exhibiting partial D-J rearrangement. In contrast, Sca+Lin- cells from Ig transgenic mice that were cultured similarly expressed B220, CD19, IgD, intracellular and surface mu, HSA but not CD43 or BP-1. These results suggest that expression of the Ig transgene during in vitro development overcame a block in B-cell lymphopoiesis and recapitulated in vivo events. Thus, IL-7 and FL treatment allowed uncommitted stem cells to progress to the early pre-B-cell stage while similarly treated Ig transgenic cells progressed completely to the mature B-cell stage.

Animals↗
PubMed1998

Chickenpox immunisation in New Zealand.

PREVENTION: The appropriate use of varicella vaccine, effective in the prevention of chickenpox, has been considered by a Ministry of Health Working Party in 1996 and 1997, including discussion at a workshop held in Wellington, 26-27 June 1996. The introduction of varicella vaccine into the routine childhood immunisation schedule was not supported at this stage. The use of the only varicella vaccine for which the Minister of Health has given consent for distribution in New Zealand, Varilrix (SmithKline Beecham Limited), in healthy children aged nine months to 13 years inclusive, was supported. Consent has not been given for the use of Varilrix in immunocompromised people or in adults. This report discusses other groups that could be candidates for vaccination, such as children with deteriorating renal function and susceptible health care workers who regularly come into contact with especially vulnerable patients. In these cases, the vaccine would need to be administered on a named patient basis. The use of Varilrix in immunocompromised people was not supported. SURVEILLANCE: Enhanced surveillance of chickenpox and zoster are required in New Zealand. Adverse reactions to Varilrix should be carefully monitored. OUTBREAK CONTROL: There are insufficient data at present to support the use of Varilrix in outbreak control. The frequency, cost and current management of nosocomial outbreaks should be ascertained. This information may also assist in the decision whether to incorporate a varicella vaccine into the routine childhood immunisation schedule in the future.

Adolescent↗
PubMed1998

Optimising fed-batch production of recombinant proteins using the baculovirus expression vector system.

Fed-batch culture can offer significant improvement in recombinant protein production compared to batch culture in the baculovirus expression vector system (BEVS), as shown by Nguyen et al. (1993) and Bedard et al. (1994) among others. However, a thorough analysis of fed-batch culture to determine its limits in improving recombinant protein production over batch culture has yet to be performed. In this work, this issue is addressed by the optimisation of single-addition fed-batch culture. This type of fed-batch culture involves the manual addition of a multi-component nutrient feed to batch culture before infection with the baculovirus. The nutrient feed consists of yeastolate ultrafiltrate, lipids, amino acids, vitamins, trace elements, and glucose, which were added to batch cultures of Spodoptera frugiperda (Sf9) cells before infection with a recombinant Autographa californica nuclear polyhedrosis virus (AcNPV) expressing beta-galactosidase (beta-Gal). The fed-batch production of beta-Gal was optimised using response surface methods (RSM). The optimisation was performed in two stages, starting with a screening procedure to determine the most important variables and ending with a central-composite experiment to obtain a response surface model of volumetric beta-Gal production. The predicted optimum volumetric yield of beta-Gal in fed-batch culture was 2.4-fold that of the best yields in batch culture. This result was confirmed by a statistical analysis of the best fed-batch and batch data (with average beta-Gal yields of 1.2 and 0.5 g/L, respectively) obtained from this laboratory. The response surface model generated can be used to design a more economical fed-batch operation, in which nutrient feed volumes are minimised while maintaining acceptable improvements in beta-Gal yield.

Animals↗
PubMed1998

A rapid precurarization technique using rocuronium.

PURPOSE: To evaluate a rapid and time-saving precurarization technique using rocuronium to prevent succinylcholine-induced myalgia. METHOD: In a prospective, double blind randomized study, 42 ASA 1-2 patients were assigned to one of three pretreatment groups: 0.01 ml.kg-1 normal saline, 0.1 mg.kg-1 atracurium, and 0.1 mg.kg-1 rocuronium. Anaesthesia commenced with 1.5 micrograms.kg-1 fentanyl and 0.5 mg.kg-1 lidocaine at time zero. Pretreatment was administered 60 sec later, followed by 2.5 mg.kg-1 propofol. At 90 sec, 1.5 mg.kg-1 succinylcholine was injected and 30 sec later, the trachea was intubated and the ease of intubation was graded. The patient was observed for the presence and severity of fasciculations. Myalgias were recorded on postoperative days 1, 2 and 7. RESULTS: The incidence of fasciculations in the rocuronium group (21.4%) was lower (P < 0.001) than atracurium (78.5%) or placebo (92.8%) groups. On postoperative day 1, the incidence of postoperative myalgia in the rocuronium group (14.2%) was less than the placebo group (78.2%; P < 0.002) and atracurium group (85.7%; P < 0.001). The incidence of myalgia in the rocuronium group (7.1%) was lower than in the placebo group (78.5%; P < 0.001) but not different from the atracurium group (42.8%; P = 0.077) on postoperative day 2. On postoperative day 7, there was no difference among the three groups. Fasciculations were related to postoperative myalgia. There was no difference in intubating conditions among the three groups. CONCLUSION: Rocuronium pretreatment given just before induction of anaesthesia with propofol reduces fasciculations and succinylcholine-induced myalgia.

Adult↗
PubMed1998

An in vitro approach for the characterization of the cycling B cell response.

Because isolation of sufficient numbers of cycling, germinal center B cells from mice for biochemical characterization of BCR-derived signals can be problematic, we have designed an experimental approach for generating large numbers of cycling B cells for further study. In the experiments reported here, small, resting B cells were polyclonally stimulated with lipopolysaccharide (LPS), and cycling B cells isolated as two bands on three-step Percoll gradients. Cycling B cells isolated at Days 2, 4, or 6 of preactivation showed an increased expression of Fas receptor and peanut agglutinin binding, with a concomitant decrease in sIgD positivity. These cells phenotypically resembled extrafollicular or early germinal center B cells. These cycling B cells were used to study the functional consequences of differential signaling through the BCR. Strong cross-linking of BCR, by restimulation of cycling normal B cells with either immobilized or soluble F(ab')2 anti-mu and cycling hen egg lysozyme (HEL) transgenic B cells with either soluble or immobilized HEL, extended cellular proliferation by 2-3 d. In contrast, cycling B cells either restimulated with soluble, whole anti-mu (to mimic binding of soluble immune complexes) or cultured in the absence of restimulation (to mimic cycling B cells not competitive for antigen) resulted in the rapid exit of the cells from cycle. This system will enable the molecular and biochemical characterization of signal delivery to cycling B cells.

Animals↗
PubMed1998

Effect of decreased milking frequency of cows in late lactation on milk somatic cell count, polymorphonuclear leucocyte numbers, composition and proteolytic activity.

The effects of reducing the frequency of milking of cows in late lactation on milk somatic cell count (SCC), polymorphonuclear leucocyte (PMN) content, chemical composition and proteolytic activity were investigated. Intermittent milking is frequently practised by Irish farmers in late lactation, and the objective of this study was to determine whether this procedure could be linked to altered quality of milk. Seventeen Holstein Friesian cows in late lactation (> 215 d in milk) were assigned to two treatment groups, and were either milked twice a day until drying-off (control group) or milked intermittently as the yield fell (test group). Milk composition and enzymic characteristics were measured on two occasions. At the first sampling, day 7, test cows were on once daily milking and at the second, day 15, the test cows were being milked every second day. Milk yields were significantly lower in test than control animals and decreased between days 7 and 15 in both groups. Milk SCC and PMN levels were increased on reducing milking frequency and, at day 15, the increase was not linked to decreased milk yield. Milk lactose levels were significantly decreased and pH, alpha-lactalbumin levels, plasmin activity and plasminogen activity significantly increased by reducing milking frequency. In conclusion, reduced frequency of milking in late lactation leads to the production of milk that is abnormal in character and this may be linked to reduced quality of dairy products manufactured from such milk.

Animals↗
PubMed1998

Efficacy of Zoladex LA (goserelin) in the treatment of girls with central precocious or early puberty.

OBJECTIVE: To assess the efficacy of a longer acting preparation of the gonadotrophin releasing hormone (GnRH) analogue goserelin (Zoladex LA, 10.8 mg) in 12 girls with central precocious or early puberty. METHODS: Two girls started treatment de novo; the remainder had been on suppressive treatment for a median duration of 1.5 (range, 0.2-5.6) years. Assessment comprising auxology, pubertal staging, and pelvic ultrasound examination was carried out at weeks 0, 4, 8, 10, and 12 (first cycle) and weeks 8, 10, and 12 (second cycle) to evaluate the required injection frequency. Thereafter, assessment was performed on the day of injection. Zoladex LA was given every 12 weeks unless pubertal progression occurred. RESULTS: Satisfactory control was achieved in eight patients using this regimen, and three patients required more frequent injections. One girl was removed from the study because of clinical progression and extreme mood swings. No serious adverse effects occurred. Mean height velocity during the study period was 4.5 cm/year (range, 3.1-6.6) compared with 6.5 cm/year (range, 3.8-9.6) before treatment in nine patients for whom data were available. CONCLUSIONS: Zoladex LA was effective in controlling precocious puberty in girls when given at intervals of 9-12 weeks and it is recommended that an initial assessment is made eight weeks after beginning treatment.

Antineoplastic Agents, Hormonal↗
PubMed1997

Early physician notification of patient disability risk and clinical guidelines after low back injury: a randomized, controlled trial.

STUDY DESIGN: Back-injured workers with high disability risk scores on a predictive questionnaire participated in a randomized, controlled trial of physician notification, with outcomes follow-up 3 months after injury. OBJECTIVES: To test whether physician intervention improves return to work and self-assessment outcomes for people at relatively high risk for disability. SUMMARY OF BACKGROUND DATA: Only a small number of back-injured workers suffer significant disability. Quick identification of these people would facilitate more efficient targeting and trials of interventions. Controlling variations in practice through practice guidelines has been recommended as a promising strategy for improving care and reducing disability. METHODS: Workers filing back injury reports responded to a disability prediction questionnaire. Those with high risk scores were randomly assigned to control or intervention groups. Patient-designated physicians in the intervention group received two letters identifying the patient's risk and making recommendations for care, including the Agency for Health Care Policy and Research's algorithms for acute low back pain. Predictive accuracy of the questionnaire and efficacy of physician intervention were evaluated on the basis of work status and self-assessments 3 months after injury. RESULTS: Of the 268 workers completing the questionnaire portion of the study, 32 (12%) were out of work because of back pain 3 months after injury. The questionnaire's predictive accuracy included maximum kappa of 0.277 and a receiver operating curve area of 0.78. Fifty-three people completed the physician intervention trial. The intervention had no significant impact on return to work, self-assessed pain, or satisfaction with health care. CONCLUSIONS: Stratification of back-injured people according to disability risk can can increase intervention efficiency by identifying those who require treatment and sparing those who do not. The apparent failure of risk notification and practice guidelines to reduce disability in this study may be improved by different application methods in the future.

Adolescent↗
PubMed1997

Measles control.

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Humans↗