Biomedical subjects

Jennifer Schneider

Publications and source records attributed to Jennifer Schneider.

8 recordsLinked to original sources

PubMed2006

A quantitative trait locus (QTL) on chromosome 6q influences birth weight in two independent family studies.

Low birth weight is an important cause of infant mortality and morbidity worldwide. Birth weight has been shown to be inversely correlated with adult complex diseases such as obesity, type-2 diabetes and cardiovascular disease. However, little is known about the genetic factors influencing variation in birth weight and its association with diseases that occur in later life. We, therefore, have performed a genome-wide search to identify genes that influence birth weight in Mexican-Americans using the data from the San Antonio Family Birth Weight Study participants (n=840). Heritability of birth weight was estimated as 72.0+/-8.4% (P<0.0001) after adjusting for the effects of sex and term. Multipoint linkage analysis yielded the strongest evidence for linkage of birth weight (LOD=3.7) between the markers D6S1053 and D6S1031 on chromosome 6q. This finding has been replicated (LOD=2.3) in an independent European-American population. Together, these findings provide substantial evidence (LOD(adj)=4.3) for a major locus influencing variation in birth weight. This region harbors positional candidate genes such as chorionic gonadotropin, alpha chain; collagen, type XIX, alpha-1; and protein-tyrosine phosphatase, type 4A, 1 that may play a role in fetal growth and development. In addition, potential evidence for linkage (LOD>or=1.2) was found on chromosomes 1q, 2q, 3q, 4q, 9p, 19p and 19q with LODs ranging from 1.3 to 2.7. Thus, we have found strong evidence for a major gene on chromosome 6q that influences variation in birth weight in both Mexican- and European-Americans.

Birth Weight↗

PubMed2006

A genomewide search finds major susceptibility loci for gallbladder disease on chromosome 1 in Mexican Americans.

Gallbladder disease (GBD) is one of the major digestive diseases. Its risk factors include age, sex, obesity, type 2 diabetes, and metabolic syndrome (MS). The prevalence of GBD is high in minority populations, such as Native and Mexican Americans. Ethnic differences, familial aggregation of GBD, and the identification of susceptibility loci for gallstone disease by use of animal models suggest genetic influences on GBD. However, the major susceptibility loci for GBD in human populations have not been identified. Using ultrasound-based information on GBD occurrence and a 10-cM gene map, we performed multipoint variance-components analysis to localize susceptibility loci for GBD. Phenotypic and genotypic data from 715 individuals in 39 low-income Mexican American families participating in the San Antonio Family Diabetes/Gallbladder Study were used. Two GBD phenotypes were defined for the analyses: (1) clinical or symptomatic GBD, the cases of cholecystectomies due to stones confirmed by ultrasound, and (2) total GBD, the clinical GBD cases plus the stone carriers newly diagnosed by ultrasound. With use of the National Cholesterol Education Program/Adult Treatment Panel III criteria, five MS risk factors were defined: increased waist circumference, hypertriglyceredemia, low high-density lipoprotein cholesterol, hypertension, and high fasting glucose. The MS risk-factor score (range 0-5) for a given individual was used as a single, composite covariate in the genetic analyses. After accounting for the effects of age, sex, and MS risk-factor score, we found stronger linkage signals for the symptomatic GBD phenotype. The highest LOD scores (3.7 and 3.5) occurred on chromosome 1p between markers D1S1597 and D1S407 (1p36.21) and near marker D1S255 (1p34.3), respectively. Other genetic locations (chromosomes 2p, 3q, 4p, 8p, 9p, 10p, and 16q) across the genome exhibited some evidence of linkage (LOD >or=1.2) to symptomatic GBD. Some of these chromosomal regions corresponded with the genetic locations of Lith loci, which influence gallstone formation in mouse models. In conclusion, we found significant evidence of major genetic determinants of symptomatic GBD on chromosome 1p in Mexican Americans.

Adult↗

PubMed2006

A genome-wide linkage scan for genes controlling variation in renal function estimated by serum cystatin C levels in extended families with type 2 diabetes.

We performed a variance components linkage analysis of renal function, measured as glomerular filtration rate (GFR), in 63 extended families with multiple members with type 2 diabetes. GFR was estimated from serum concentrations of cystatin C and creatinine in 406 diabetic and 428 nondiabetic relatives. Results for cystatin C were summarized because they are superior to creatinine results. GFR aggregates in families with significant heritability (h(2)) in diabetic (h(2) = 0.45, P < 1 x 10(-5)) and nondiabetic (h(2) = 0.36, P < 1 x 10(-3)) relatives. Genetic correlation (r(G) = 0.35) between the GFR of diabetic and nondiabetic relatives was less than one (P = 0.01), suggesting that genes controlling GFR variation in these groups are different. Linkage results supported this interpretation. In diabetic relatives, linkage was strong on chromosome 2q (logarithm of odds [LOD] = 4.1) and suggestive on 10q (LOD = 3.1) and 18p (LOD = 2.2). In nondiabetic relatives, linkage was suggestive on 3q (LOD = 2.2) and 11p (LOD = 2.1). When diabetic and nondiabetic relatives were combined, strong evidence for linkage was found only on 7p (LOD = 4.0). In conclusion, partially distinct sets of genes control GFR variation in relatives with and without diabetes on chromosome 2q, possibly on 10q and 18p in the former, and on 7p in both. None of these genes overlaps with genes controlling variation in urinary albumin excretion.

Adult↗

PubMed2005

IRIS and SLE.

Explore the source record for details and available documents.

Adult↗

PubMed2004

How to design computerized alerts to safe prescribing practices.

BACKGROUND: Medication errors and preventable adverse drug events are common, and about half of medication errors occur during medication ordering. This study was designed to develop and evaluate medication safety alerts and processes for educating prescribers about the alerts. METHODS: At Kaiser Permanente Northwest, a group-model health maintenance organization where prescribers have used computerized order entry since 1996, qualitative interviews were conducted with 20 primary care prescribers. RESULTS: Prescribers considered alerts helpful for providing prescribing and preventive health information. More than half the interviewees stated that it would be unwise to let clinicians control or avoid safety alerts. Common frustrations were (1) being delayed by the alert, (2) having difficulty interpreting the alert, and (3) receiving the same alert repeatedly. Most prescribers preferred small-group educational sessions tied to existing meetings and having local physicians conduct education sessions. DISCUSSION: The findings were used to design a strategy for introducing and promoting the interventions, modifying the alert text and tools, and focusing the education on how clinicians could use the alerts effectively.

Attitude of Health Personnel↗

PubMed2003

Evidence for bivariate linkage of obesity and HDL-C levels in the Framingham Heart Study.

BACKGROUND: Epidemiological studies have indicated that obesity and low high-density lipoprotein (HDL) levels are strong cardiovascular risk factors, and that these traits are inversely correlated. Despite the belief that these traits are correlated in part due to pleiotropy, knowledge on specific genes commonly affecting obesity and dyslipidemia is very limited. To address this issue, we first conducted univariate multipoint linkage analysis for body mass index (BMI) and HDL-C to identify loci influencing variation in these phenotypes using Framingham Heart Study data relating to 1702 subjects distributed across 330 pedigrees. Subsequently, we performed bivariate multipoint linkage analysis to detect common loci influencing covariation between these two traits. RESULTS: We scanned the genome and identified a major locus near marker D6S1009 influencing variation in BMI (LOD = 3.9) using the program SOLAR. We also identified a major locus for HDL-C near marker D2S1334 on chromosome 2 (LOD = 3.5) and another region near marker D6S1009 on chromosome 6 with suggestive evidence for linkage (LOD = 2.7). Since these two phenotypes have been independently mapped to the same region on chromosome 6q, we used the bivariate multipoint linkage approach using SOLAR. The bivariate linkage analysis of BMI and HDL-C implicated the genetic region near marker D6S1009 as harboring a major gene commonly influencing these phenotypes (bivariate LOD = 6.2; LODeq = 5.5) and appears to improve power to map the correlated traits to a region, precisely. CONCLUSIONS: We found substantial evidence for a quantitative trait locus with pleiotropic effects, which appears to influence both BMI and HDL-C phenotypes in the Framingham data.

Adult↗

PubMed2003

Willingness to participate in complementary and alternative medicine clinical trials among patients with craniofacial disorders.

OBJECTIVES: The Oregon Center for Complementary and Alternative Medicine (OCCAM) conducted focus groups with participants to determine willingness to join a complementary and alternative medicine (CAM) research study, and to aid in the design of three clinical randomized controlled trials (RCTs) of CAM and craniofacial disorders. SETTING/LOCATION: Center for Health Research, Kaiser Permanente, in Portland, Oregon. SUBJECTS: Kaiser Permanente health plan members meeting RCT inclusion criteria. DESIGN: Twelve (12) focus groups were conducted with a total of 85 participants. Six (6) of the focus groups were with members who self-identified as users of CAM therapies. Focus groups explored participants' experiences of CAM for temporomandibular disorder (TMD) and periodontal disease, and their reactions to proposed aspects of the trials. Trained facilitators led the focus groups, which lasted approximately 2 hours and were audiotaped for future transcription. Researchers then coded the transcripts to identify responses to specific questions and to capture emergent themes. RESULTS: Acupuncture, chiropractic, and massage were most frequently accessed and reported as helpful by participants. Participants who had not used CAM treatments for their condition expressed interest and openness to experiencing CAM treatments through a research study. In general, participants expressed willingness to be randomly assigned to (rather than choose) a CAM treatment arm. Travel to practitioners' offices and frequent (> 1 per week) visits were acceptable to most participants, if there was flexibility in appointment scheduling. CONCLUSIONS: Findings indicate considerable willingness to engage in CAM trials, even among individuals who have not used CAM. Participants' willingness to engage in CAM studies was influenced by the nature of their condition, their prior experiences with conventional and CAM treatments, and the possibility of experiencing CAM "for free" through participation in the trial. Their acceptance also was tempered by concerns about particular modalities and the possibility of having to give up aspects of their current health routine. Researchers engaging in CAM studies should take these factors into consideration as they design studies.

Adult↗

PubMed2003

Use of complementary and alternative medicine for temporomandibular disorders.

AIMS: Despite many reports about complementary and alternative medicine (CAM) use in the general population, little information exists about specific CAM therapies used for particular health conditions. This study examines the use of CAM therapies among patients with temporomandibular disorders (TMD). METHODS: We surveyed 192 patients with documented TMD as part of a larger project on the effectiveness of various CAM modalities for TMD patients. The survey asked about use of and attitudes toward specific CAM therapies for treating TMD and other patient-identified health conditions. The survey also measured physical health, health behavior, and psychosocial functioning. RESULTS: Nearly two thirds of the respondents (62.5%; n = 120) reported using CAM therapies for TMD or a related condition. Of all the therapies reported, massage was rated as the most frequent and among the most satisfactory and helpful. In general, respondents who used CAM for their TMD reported being most satisfied with the "hands on" CAM therapies (massage, acupuncture, and chiropractic care). The vast majority of respondents reported using CAM approaches for TMD simultaneously with conventional care (95.6%; 66 of 69). Those using CAM for TMD tended to be older, had a history of multiple medical problems, and reported more positive psychologic functioning. Respondents who most often reported CAM treatment as "very helpful" for their TMD were likely to be healthier (i.e., reporting higher levels of exercise and fewer sleep disturbances). CONCLUSION: Given the frequent use of CAM treatments by our respondents, allopathic providers should inquire about the adjunctive use of CAM among their TMD patients.

Adolescent↗