PubMed Health⌕ Search

Biomedical subjects

David Evans

Publications and source records attributed to David Evans.

At least 19 recordsLinked to original sources

The E670G SNP in the PCSK9 gene is associated with polygenic hypercholesterolemia in men but not in women.

BACKGROUND: Common genetic variants in the PCSK9 gene have been reported to be associated with both elevated and exceptionally low LDL levels. The association of a common haplotype, encompassing the E670G single nucleotide polymorphism, with LDL levels reported by Chen et al (J Am Coll Cardiol 2005; 45: 1644) was not confirmed by Kotowski et al (Am J Hum Genet 2006; 78:410-422). METHODS: The incidence of the E670G SNP was determined in 506 patients attending the lipid clinic, University Hospital, Hamburg. RESULTS: The frequency in men with polygenic hypercholesterolemia, 0.11 was significantly higher than in men with LDL<50th percentile, 0.03, p = 0.01. In women there was no difference in the allele frequencies between the two groups. CONCLUSION: In a European population the E670G SNP in the PCSK9 gene is associated with increased LDL in men but not in women.

Adult↗

Self-reported moisture or mildew in the homes of Head Start children with asthma is associated with greater asthma morbidity.

This study used results from a cross-sectional survey of parents of 3- to 5-year-old children with asthma to assess the frequency of self-reported home environmental conditions that could contribute to worsening asthma and examined the relationship between these factors and the child's asthma morbidity. Participants were 149 parents drawn from the two largest agencies that provide subsidized preschool childcare services in East and Central Harlem, inner-city communities with high prevalence of asthma. The sample represented 77% of eligibles determined by a validated case-identification instrument. Data were collected on demographics, symptoms, medication use, Emergency Department visits and hospitalization, and environmental conditions in the home. One or more of these home environmental conditions were reported by 92% of participants. Controlling for other environmental conditions and demographics, associations were found between self-reported presence of moisture or mildew on ceilings, walls, or windows and higher frequency of hospitalizations for breathing-related problems (OR = 3.31; 95% CI 1.62-6.75), frequent episodes of wheezing (OR = 3.25; 95% CI 1.8-6.0), and higher frequency of night symptoms due to asthma (OR = 2.19; 95% CI 1.4-3.41). Having a carpet or rug in the child's bedroom or the living room was also associated with hospitalizations (OR = 3.23; 95% CI 1.53-6.8), and male gender was marginally associated with the frequency of night symptoms (OR = 1.51; 95% CI .95-2.4). Asthma is prevalent in the Head Start population, and exposure to home environmental conditions that may worsen asthma is common in the socially disadvantaged populations served by Head Start programs.

Allergens↗

Determinants of cockroach and mouse exposure and associations with asthma in families and elderly individuals living in New York City public housing.

BACKGROUND: Asthma prevalence is high in the inner city, and morbidity has been associated with cockroach and mouse allergens. OBJECTIVE: To characterize the relationships among pests, allergens, pesticides, and asthma in New York City public housing. METHODS: In 324 apartments, dust samples collected from beds and kitchens were analyzed for cockroach (Bla g 2) and mouse (mouse urinary protein [MUP]) allergens, pest populations were monitored, and residents were interviewed about home characteristics and asthma symptoms. RESULTS: Cockroaches were found in 77% of the apartments, and evidence of mice was found in 13%. Allergens and pesticide use were associated with pest infestation, and 15% of residents reported using illegal pesticides. The percentage of apartments with high allergen levels varied significantly by building (Bla g 2: P = .002; MUP: P = .03), as did the percentage of apartments with cockroaches (P = .002) and daily mouse sightings (P = .02). Thirty-seven percent of the apartments had at least 1 resident with physician-diagnosed asthma. In family buildings, apartments with high Bla g 2 levels had 1.7 times greater odds of having an asthmatic resident (95% confidence interval, 1.2-2.3). In senior citizen buildings, apartments with high MUP levels had 6.6 times greater odds of having an asthmatic resident (95% confidence interval, 1.4-31.7), controlling for smoking and other potential confounders. CONCLUSIONS: Previous studies have identified home characteristics associated with the presence of cockroaches and mice, but the present findings suggest that building-level characteristics can affect high pest exposure. Furthermore, the high asthma prevalence in residents and the use of illegal pesticides highlight the need for safe and effective building-wide pest control strategies.

Adolescent↗

Using school staff to establish a preventive network of care to improve elementary school students' control of asthma.

School-based asthma interventions delivered by nonschool staff have been successful but are limited in their reach because of the cost and effort of bringing in outside educators and their inability to establish improved communication about asthma between schools, families, and primary care providers (PCPs). To address these problems, Columbia University and the New York City Department of Education and the New York City Department of Health and Mental Hygiene undertook a randomized controlled trial to test the efficacy of a comprehensive school-based asthma program. In this intervention, school nurses were trained to facilitate the establishment of a preventive network of care for children with asthma by coordinating communications and fostering relationships between families, PCPs, and school personnel. PCPs also received training regarding asthma management. There was limited support for this model. While case detection helped nurses identify additional students with asthma and nurses increased the amount of time spent on asthma-related tasks, PCPs did not change their medical management of asthma. Few improvements in health outcomes were achieved. Relative to controls, 12-months posttest intervention students had a reduction in activity limitations due to asthma (-35% vs -9%, p < .05) and days with symptoms (26% vs 39%, p = .06). The intervention had no impact on the use of urgent health care services, school attendance, or caregiver's quality of life. There were also no improvements at 24-months postintervention. We faced many challenges related to case detection, training, and implementing preventive care activities, which may have hindered our success. We present these challenges, describe how we coped with them, and discuss the lessons we learned.

Absenteeism↗

Validating an asthma case detection instrument in a Head Start sample.

Although specific tests screen children in preschool programs for vision, hearing, and dental conditions, there are no published validated instruments to detect preschool-age children with asthma, one of the most common pediatric chronic conditions affecting children in economically disadvantaged communities of color. As part of an asthma education intervention, a 15-item Brief Respiratory Questionnaire (BRQ) was developed to detect children with probable asthma in Head Start and subsidized preschool settings in communities with high asthma prevalence and associated morbidity. Preschool personnel administered the BRQ to consenting parents of 419 enrolled children. Trained interviewers administered validation interviews (VALs) to parents of 149 case-positive children and 51 case-negative children. Three physicians independently assessed deidentified summaries of the VALs that captured responses about signs and symptoms of asthma, diagnosis and treatment, and use of medical services. The physicians' assessments of the summarized VALs were the validated standard to which the BRQ classifications were compared. A simple algorithm of 4 items was identified that can be administered and scored by nonmedical preschool personnel in less than 5 minutes. The chance-corrected agreement between these 4 items of the BRQ and the VAL was good: kappa, .73 (95% confidence interval, 0.62-0.84); specificity, 96%; sensitivity, 73%; and positive predictive value, 97%. The BRQ appears to be a valid instrument for detecting children with probable asthma in Head Start and other subsidized preschool settings in communities with high prevalence of asthma.

Allergens↗

Impact of physician asthma care education on patient outcomes.

OBJECTIVE: We evaluated the effectiveness of a continuing medical education program, Physician Asthma Care Education, in improving pediatricians' asthma therapeutic and communication skills and patients' health care utilization for asthma. METHODS: We conducted a randomized trial in 10 regions in the United States. Primary care providers were recruited and randomly assigned by site to receive the program provided by local faculty. The program included 2 interactive seminar sessions (2.5 hours each) that reviewed national asthma guidelines, communication skills, and key educational messages. Format included short lectures, case discussions, and a video modeling communication techniques. We collected information on parent perceptions of physicians' communication, the child's asthma symptoms, and patients' asthma health care utilization. We used multivariate regression models to determine differences between control and intervention groups. RESULTS: A total of 101 primary care providers and a random sample of 870 of their asthma patients participated. After 1 year, we completed follow-up telephone interviews with the parents of 731 of the 870 patients. Compared to control subjects, parents reported that physicians in the intervention group were more likely to inquire about patients' concerns about asthma, encourage patients to be physically active, and set goals for successful treatment. Patients of physicians that attended the program had a greater decrease in days limited by asthma symptoms (8.5 vs 15.6 days), as well as decreased emergency department asthma visits (0.30 vs 0.55 visits per year). CONCLUSIONS: The Physician Asthma Care Education program was used in a range of locations and was effective in improving parent-reported provider communication skills, the number of days affected by asthma symptoms, and asthma health care use. Patients with more frequent asthma symptoms and higher health care utilization at baseline were more likely to benefit from their physician's participation in the program.

Asthma↗

Interleukin-1beta and signaling of interleukin-1 in vascular wall and circulating cells modulates the extent of neointima formation in mice.

Interleukin (IL)-1 is an important mediator of inflammation and cardiovascular disease. Here, we examined the role of IL-1 in arterial neointima formation. Carotid artery neointima was induced by ligation, and arteries were harvested 4 weeks after injury. The neointima/media of mice deficient in the IL-1 signaling receptor (IL-1R1(-/-)) was significantly reduced compared to IL-1R1(+/+) controls (P < 0.01). IL-1R1(+/+) mice receiving subcutaneous IL-1ra also had significantly reduced neointima/media compared with placebo (P < 0.05). IL-1beta(-/-) mice had reduced neointima/media compared to wild-type (P < 0.05), whereas IL-1alpha(-/-) mice were no different from controls. Mice deficient in the P2X(7) receptor (involved in IL-1 release) or caspase-1 (involved in IL-1 activation) did not differ in their response to carotid ligation compared to controls. To examine the site of IL-1 signaling, we generated chimeric mice. IL-1R1(+/+) mice receiving IL-1R1(-/-) marrow and IL-1R1(-/-) mice receiving IL-1R1(+/+) marrow both had significantly reduced neointima/media compared with IL-1R1(+/+) to IL-1R1(+/+) (P < 0.05) but had significantly greater neointima/media than IL-1R1(-/-) to IL-1R1(-/-) controls (P < 0.05). These data confirm the importance of IL-1beta signaling in mediating arterial neointima formation and suggest the involvement of IL-1 signaling in both circulating and arterial wall cells. Furthermore, receptor antagonism may be a better therapeutic target than interruption of IL-1beta processing or release.

Animals↗

Does home based medication review keep older people out of hospital? The HOMER randomised controlled trial.

OBJECTIVE: To determine whether home based medication review by pharmacists affects hospital readmission rates among older people. DESIGN: Randomised controlled trial. SETTING: Home based medication review after discharge from acute or community hospitals in Norfolk and Suffolk. PARTICIPANTS: 872 patients aged over 80 recruited during an emergency admission (any cause) if returning to own home or warden controlled accommodation and taking two or more drugs daily on discharge. INTERVENTION: Two home visits by a pharmacist within two weeks and eight weeks of discharge to educate patients and carers about their drugs, remove out of date drugs, inform general practitioners of drug reactions or interactions, and inform the local pharmacist if a compliance aid is needed. Control arm received usual care. MAIN OUTCOME MEASURE: Total emergency readmissions to hospital at six months. Secondary outcomes included death and quality of life measured with the EQ-5D. RESULTS: By six months 178 readmissions had occurred in the control group and 234 in the intervention group (rate ratio = 1.30, 95% confidence interval 1.07 to 1.58; P = 0.009, Poisson model). 49 deaths occurred in the intervention group compared with 63 in the control group (hazard ratio = 0.75, 0.52 to 1.10; P = 0.14). EQ-5D scores decreased (worsened) by a mean of 0.14 in the control group and 0.13 in the intervention group (difference = 0.01, -0.05 to 0.06; P = 0.84, t test). CONCLUSIONS: The intervention was associated with a significantly higher rate of hospital admissions and did not significantly improve quality of life or reduce deaths. Further research is needed to explain this counterintuitive finding and to identify more effective methods of medication review.

Aftercare↗

Ensuring a scientific basis for community interventions for asthma.

Community based interventions are an important part of public health management of many diseases, including asthma. However, there are few scientifically proven and readily available community interventions for asthma. In an effort to increase the number of available interventions, we have identified ongoing asthma intervention research, identified potentially effective asthma interventions based on completed research, and prepared several of the effective interventions for widespread implementation through a process called "translation." We provide an example of one of these effective interventions now available for widespread implementation, "Creating a medical home for asthma." This intervention grew out of need for an intervention in New York City Department of Health (NYCDOH) clinics. The intervention includes training all clinic staff in a comprehensive, preventive approach to asthma care. All of the materials needed to implement the intervention are available to all through the NYCDOH web site (www.nyc.gov/ html/doh/html/cmha/index.html). This example points to the importance of making the tools needed to implement effective interventions available across the country and the role of public/private partnerships to assure the availability of science-based interventions for asthma control.

Asthma↗

Identity and emergency intervention: how social group membership and inclusiveness of group boundaries shape helping behavior.

Two experiments exploring the effects of social category membership on real-life helping behavior are reported. In Study 1, intergroup rivalries between soccer fans are used to examine the role of identity in emergency helping. An injured stranger wearing an in-group team shirt is more likely to be helped than when wearing a rival team shirt or an unbranded sports shirt. In Study 2, a more inclusive social categorization is made salient for potential helpers. Helping is extended to those who were previously identified as out-group members but not to those who do not display signs of group membership. Taken together, the studies show the importance of both shared identity between bystander and victim and the inclusiveness of salient identity for increasing the likelihood of emergency intervention.

Adolescent↗

Integrated allosteric regulation in the S. cerevisiae carbamylphosphate synthetase - aspartate transcarbamylase multifunctional protein.

BACKGROUND: The S. cerevisiae carbamylphosphate synthetase - aspartate transcarbamylase multifunctional protein catalyses the first two reactions of the pyrimidine pathway. In this organism, these two reactions are feedback inhibited by the end product UTP. In the present work, the mechanisms of these integrated inhibitions were studied. RESULTS: The results obtained show that the inhibition is competitive in the case of carbamylphosphate synthetase and non-competitive in the case of aspartate transcarbamylase. They also identify the substrate whose binding is altered by this nucleotide and the step of the carbamylphosphate synthetase reaction which is inhibited. Furthermore, the structure of the domains catalyzing these two reactions were modelled in order to localize the mutations which, specifically, alter the aspartate transcarbamylase sensitivity to the feedback inhibitor UTP. Taken together, the results make it possible to propose a model for the integrated regulation of the two activities of the complex. UTP binds to a regulatory site located in the vicinity of the carbamylphosphate synthetase catalytic subsite which catalyzes the third step of this enzyme reaction. Through a local conformational change, this binding decreases, competitively, the affinity of this site for the substrate ATP. At the same time, through a long distance signal transmission process it allosterically decreases the affinity of the aspartate transcarbamylase catalytic site for the substrate aspartate. CONCLUSION: This investigation provides informations about the mechanisms of allosteric inhibition of the two activities of the CPSase-ATCase complex. Although many allosteric monofunctional enzymes were studied, this is the first report on integrated allosteric regulation in a multifunctional protein. The positions of the point mutations which specifically abolish the sensitivity of aspartate transcarbamylase to UTP define an interface between the carbamylphosphate synthetase and aspartate transcarbamylase domains, through which the allosteric signal for the regulation of aspartate transcarbamylase must be propagated.

Allosteric Regulation↗

Clinical performance of 'no rub' multi-purpose solutions.

This was a multi-site, 231-subject double-masked, bilateral crossover study to evaluate subjective comfort and satisfaction, corneal staining and lens deposits with two 'no rub' multi-purpose solutions (MPS) used with FDA Group II (alphafilcon A, SofLens 66, Bausch & Lomb) and Group IV (etafilcon A, SUREVUE, Johnson & Johnson Vision Care) soft contact lenses. Subjects used each of the two MPS, Regimen 1 (OPTI-FREE EXPRESS Multi-Purpose Disinfecting Solution No Rub Lasting Comfort Formula, Alcon Laboratories) and Regimen 2 (ReNu MultiPlus Multi-Purpose Solution, Bausch & Lomb), for 28 days. They wore the same lens type for the duration of the study and were evaluated on days 0, 14 and 28 of each treatment period. Subjective ratings of comfort and satisfaction were significantly different between regimens, with the majority of variables in favour of Regimen 1 (P < 0.05). Corneal staining was significantly greater with the Group II, Regimen 2 combination (P < 0.0001). Group IV lenses cared for with Regimen 1 had significantly less residual lysozyme on Day 28 (562 microg) than lenses cared for with Regimen 2 (1145 microg; P < 0.0001). While both products offer the convenience of a 'no rub' regimen, differences in performance should be considered when recommending these solutions to patients.

Journal Article↗

Asthma education: the adolescent experience.

Recent studies show that prevalence of asthma is higher among adolescents than children. Adolescents have poor asthma self-management skills resulting in a significant increase in the severity of asthma exacerbations and a reduction in their quality of life. Despite this, few self-management programs have been developed for adolescents. Adolescents experience developmental transitions that both hinder and facilitate asthma self-management. In this paper we discuss developmental transitions in cognition, knowledge, autonomy, identity development, and peer relations in terms of their influence on adolescents' management of asthma. Next, we describe the Asthma Self-Management for Adolescents (ASMA) program that incorporates developmental characteristics into an age-appropriate school-based asthma education program. Preliminary data is presented indicating that the program is successful in enrolling and engaging the interest of adolescents with persistent asthma.

Adolescent↗

Educating health professionals to improve quality of care for asthma.

Recent studies have shown significant progress in improving the quality of care for asthma. The most successful interventions have combined multiple elements: educational sessions that engage learners in discussing cases and practicing new skills; use of new resources, tools and practice patterns to enable quality improvement; and reinforcement of improvements through peer support, incentives or administrative review. Future research should include more randomised controlled trials to test the effectiveness of quality improvement interventions, more detailed descriptions of strategies to change health professional behaviour and studies to determine whether effective interventions can be translated to other settings, disseminated widely and sustained over time.

Asthma↗

Pesticide sales in low-income, minority neighborhoods.

The US EPA has phased-out residential use of two organophosphate pesticides commonly used to control cockroaches-retail sales of chlorpyrifos were scheduled to end on 12/31/01, and diazinon on 12/31/02. In light of recent findings highlighting the associations between pests, pesticides and health, we surveyed stores in low-income, minority neighborhoods in New York City to determine whether the phase-outs have been effective and to assess the availability of alternatives to spray pesticides. In summer 2002, when sales of chlorpyrifos were illegal and diazinon still legal, we surveyed 106 stores selling pesticides. Four percent sold products containing chlorpyrifos and 40 percent sold products containing diazinon. One year later, when sales of both pesticides were to have ended, we surveyed 109 stores selling pesticides in the same neighborhoods and found chlorpyrifos in only one store and diazinon in 18 percent of stores, including 80 percent of supermarkets surveyed. At least one form of lower toxicity pesticides, including gels, bait stations and boric acid was available in 69 percent of stores in 2002. However sprays were most widely available, found in 94 percent of stores in 2002 and less expensive than lower toxicity baits and gels. In a separate survey of storekeeper recommendations conducted in 2002, storekeepers recommended lower toxicity pesticides as the best way to control cockroaches 79% of the time. The EPA's phase-outs have nearly eliminated sales of chlorpyrifos, but the diazinon phase-out appears to be less effective.

Animals↗