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Biomedical subjects

Karen Davis

Publications and source records attributed to Karen Davis.

At least 19 recordsLinked to original sources
PubMed2004

Role of residues 143 and 278 of the human nuclear Vitamin D receptor in the full-length and Delta165-215 deletion mutant.

Most of the actions of 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] are mediated by binding to the Vitamin D nuclear receptor (VDR). The crystal structure of a deletion mutant (Delta165-215) of the VDR ligand-binding domain (LBD) bound to 1,25(OH)(2)D(3) indicates that amino acid residues tyrosine-143 and serine-278 form hydrogen bonding interactions with the 3-hydroxyl group of 1,25(OH)(2)D(3). Studies of VDR and three mutants (Y143F, S278A, and Y143F/S278A) did not indicate any differences in the binding affinity between the variant receptors and the wild-type receptor. This might indicate that the 3-hydroxyl group binds differently to the full-length VDR than the to deletion mutant. To further investigate, four deletion VDR mutants were constructed: VDR(Delta165-215), VDR(Delta165-215) (Y143F), VDR(Delta165-215) (S278A), VDR(Delta165-215) (Y143F/S278A). There were no significant differences in binding affinity between the wild-type receptor and the deletion mutants except for VDR(Delta165-215) (Y143F/S278A). In gene activation assays, VDR constructs with the single mutation Y143F and the double mutation Y143F/S278A, but not the single mutation S278A required higher doses of 1,25(OH)(2)D(3) for half-maximal response. This suggests that there are some minor structural and functional differences between the wild-type VDR and the Delta165-215 deletion mutant and that Y143 residue is more important for receptor function than residue S278.

Animals↗
PubMed2004

Will consumer-directed health care improve system performance?

Consumer-directed health care plans have attracted attention as a method for managing rising health care spending by giving consumers greater financial control over their health care. However, increased cost-sharing--the principal tool used by these plans to achieve lower spending--may also cause patients to consume less care, even when that care is essential. Research studies have found that lower-income individuals and those with serious health concerns will particularly be at risk, as these consumers bear the burden of higher out-of-pocket costs. Instead of focusing solely on financial incentives, the real goal should be to encourage quality and efficiency among health systems, physicians, and hospitals.

Community Participation↗
PubMed2004

Wages, health benefits, and workers' health.

Employer-based health insurance provides the majority of U.S. workers with access to health care and protection against devastating financial losses. Millions of workers, however, do not receive health benefits from their employers, and few sources of affordable coverage exist outside the employer-based system. This study, based on data from the Commonwealth Fund Biennial Health Insurance Survey, finds a deep divide in the U.S. labor force and an urgent need for expanding access to comprehensive and affordable coverage to working Americans and their families. According to the authors, higher-wage workers are more likely than their lower-paid counterparts to have health insurance and health-related benefits, such as paid sick leave, and to use preventive care services. Low-wage workers, meanwhile, are much more likely to forgo needed health care because of cost and to report problems paying medical bills.

Adult↗
PubMed2003

Parental status of women injection drug users and entry to methadone maintenance.

This article examines patterns of methadone maintenance treatment entry among 9018 adult women injection drug users (IDUs), with special attention to parental-status differences. The data originate from a statewide drug-treatment database covering all women IDUs who entered drug treatment in the State of Massachusetts over a four-year period. Through the use of logistic regression analysis, the study found that among these women IDUs, those who resided with their children were significantly more likely to enter methadone maintenance than women who were mothers but did not reside with their children. Mothers residing with their children were 73% more likely to enter methadone maintenance than mothers who do not reside with their children. The authors discuss specific programmatic and policy implications including the need to determine whether methadone maintenance should be promoted as an alternative drug treatment option in order to preserve family unification or promote family reunification.

Adolescent↗
PubMed2003

Reach out to move up. Best practices in A/R outsourcing.

Outsourcing your practice's accounts receivable can improve efficiency, introduce better technology, stabilize your expense structure and increase patient satisfaction. It's not for everyone, but if you decide to outsource, first assess your needs, find the right vendor and negotiate a smart contract.

Accounts Payable and Receivable↗
PubMed2002

Functional profiling of the Saccharomyces cerevisiae genome.

Determining the effect of gene deletion is a fundamental approach to understanding gene function. Conventional genetic screens exhibit biases, and genes contributing to a phenotype are often missed. We systematically constructed a nearly complete collection of gene-deletion mutants (96% of annotated open reading frames, or ORFs) of the yeast Saccharomyces cerevisiae. DNA sequences dubbed 'molecular bar codes' uniquely identify each strain, enabling their growth to be analysed in parallel and the fitness contribution of each gene to be quantitatively assessed by hybridization to high-density oligonucleotide arrays. We show that previously known and new genes are necessary for optimal growth under six well-studied conditions: high salt, sorbitol, galactose, pH 8, minimal medium and nystatin treatment. Less than 7% of genes that exhibit a significant increase in messenger RNA expression are also required for optimal growth in four of the tested conditions. Our results validate the yeast gene-deletion collection as a valuable resource for functional genomics.

Cell Size↗
PubMed2002

Population genetic implications from DNA polymorphism in random human genomic sequences.

Denaturing high performance liquid chromatography (DHPLC) in combination with dye-terminator sequencing was used to survey 516 random genomic sequence tagged sites (STSs) for biallelic polymorphisms in 24 representatives of the major ethnic groups residing in the United States. Of the 301 polymorphic STSs (58.3%), 172 contained a single simple sequence polymorphism (SSP), while 78, 35, and 16 contained 2, 3, and 4-6 SSPs, respectively. Of the 541 SSPs identified, 342 (63%), 152 (28%), and 47 (9%) were transitions, transversions, and insertions or deletions, respectively. Only 21% of the STSs contained SSPs with a minor-allele frequency >20%. The nucleotide diversity estimate for random genomic sequences theta = 8.23 x 10(-4) was on average 50% higher than that for intragenic non-coding regions of the human genome ( theta = 5.52 x 10(-4). The discrepancy in Tajima's D statistic between 22 autosomal genes (D=-1.304+/-0.622, mean+/-SD) and random STSs (D=-0.27) suggests that, in the absence of significant mutation rate heterogeneity, the more negative values for genes are a consequence of directional selection rather than population growth.

Base Sequence↗
PubMed2002

The Danish health system through an American lens.

The organization and financing of the Danish health care system was evaluated within the framework of a SWOT analysis (analysis of strengths, weaknesses, opportunities and threats) by a panel of five members with a background in health economics. The evaluation was based on reading an extensive amount of selected documents and literature on the Danish health care system and a 1-week visit to health care authorities, providers and key persons. The present paper includes the main findings by one of the panel members. Primary care is much more accessible in Denmark than the USA. A mixed capitation-fee-for-service method of paying generalist physicians in Denmark ensures that everyone has a primary care physician and generalist physicians are responsive to providing services quickly, typically same-day appointments. An organized off-hours service ensures accessible care 24 h a day, 7 days a week. Denmark has the highest public satisfaction with health care, reflecting the value placed on accessibility of primary care. Inpatient hospital care consumes a disproportionate share of Danish health expenditures. Global hospital budgets provide little incentive for hospital or surgical productivity. Long waits for hospitalization, especially surgical procedures and cancellation of scheduled surgery, are a source of patient dissatisfaction. Women's health, patient health risk counseling and coordination of preventive and primary care are major weaknesses of the Danish health system. Patients have a choice of primary care physician within a given geographic area and may go to a hospital of their choice. However, patient surveys and feedback are underdeveloped and very little effort has been made to make services responsive to patients' preferences. While innovations in electronic prescribing are noteworthy, further development of health information technology is needed.

Delivery of Health Care↗
PubMedDate not supplied

Obtaining greater value from health care: the roles of the U.S. government.

The problems of quality and cost in the U.S. health care system are unlikely to be solved without strong leadership from the federal government, which can mobilize action to set national priorities for quality; develop and promulgate standards for care; and stimulate implementation of performance measures and standards for providers. All of these functions would best be carried out by a new federal agency. Furthermore, the federal government should design payment policies based on the performance standards, invest in needed information technology, and invest in research related to improving care and in training professionals to support nationwide quality improvement.

Federal Government↗
PubMedDate not supplied

Medicare versus private insurance: rhetoric and reality.

Many policymakers have called for the remodeling of Medicare to more closely resemble private insurance, which is often assumed to work better than public programs do. However, evidence from this 2001 survey demonstrates that Medicare beneficiaries are generally more satisfied with their health care than are persons under age sixty-five who are covered by private insurance. Medicare beneficiaries report fewer problems getting access to care, greater confidence about their access, and fewer instances of financial hardship as a result of medical bills. Making the program more like private insurance runs the risk of undermining a program that is working well from the perspective of beneficiaries.

Adult↗