Biomedical subjects

David E Nelson

Publications and source records attributed to David E Nelson.

27 records · Page 2Linked to original sources

PubMed2003

Transcriptome analysis of chlamydial growth during IFN-gamma-mediated persistence and reactivation.

Chlamydia trachomatis is an obligatory intracellular prokaryotic parasite that causes a spectrum of clinically important chronic inflammatory diseases of humans. Persistent infection may play a role in the pathophysiology of chlamydial disease. Here we describe the chlamydial transcriptome in an in vitro model of IFN-gamma-mediated persistence and reactivation from persistence. Tryptophan utilization, DNA repair and recombination, phospholipid utilization, protein translation, and general stress genes were up-regulated during persistence. Down-regulated genes included chlamydial late genes and genes involved in proteolysis, peptide transport, and cell division. Persistence was characterized by altered but active biosynthetic processes and continued replication of the chromosome. On removal of IFN-gamma, chlamydiae rapidly reentered the normal developmental cycle and reversed transcriptional changes associated with cytokine treatment. The coordinated transcriptional response to IFN-gamma implies that a chlamydial response stimulon has evolved to control the transition between acute and persistent growth of the pathogen. In contrast to the paradigm of persistence as a general stress response, our findings suggest that persistence is an alternative life cycle used by chlamydiae to avoid the host immune response.

Cell Division↗

PubMed2003

Consumer/provider communication research: directions for development.

Communication between health care providers and consumers is a critical part of effective health care delivery. Yet, the strategic use of interpersonal communication in health care delivery is most complex, multifaceted, and often problematic, necessitating careful study of the communication process in health care to increase understanding and help improve health communication practices. The National Cancer Institute (NCI) sponsored an expert symposium on consumer/provider communication research to examine progress and identify gaps in the research literature on doctor/patient communication. This paper and this special issue of Patient Education and Counseling reviews several of the key perspectives and suggestions presented at the symposium for directing future research and applications concerning consumer/provider communication.

Communication↗

PubMed2003

Physician advice about smoking and drinking: are U.S. adults being informed?

BACKGROUND: Population-based estimates for the prevalence of smokers receiving advice from a health professional to quit smoking and the prevalence of binge drinkers being talked to about alcohol use are lacking for U.S. adults. This information is useful for clinicians and public health professionals. METHODS: Data are from the Behavioral Risk Factor Surveillance System, a continuous random-digit-dial telephone survey of U.S. adults. In 1997, 10 states collected data on these health interventions for tobacco and alcohol use. The prevalence of professional advice to quit smoking and about alcohol use was calculated and examined by demographic characteristics. The number of at-risk adults who had a routine checkup in the last year and had not received these interventions was also estimated. RESULTS: By self-report, 70% of smokers were advised to quit, and 23% of binge drinkers were talked to about their alcohol use. Using multivariate logistic regression analyses, we found among smokers that women and older persons were more likely to receive advice; among binge drinkers, health intervention was more likely to occur for men and non-Hispanic blacks. Across the 10 states, approximately 2 million smokers and 2 million binge drinkers with a routine checkup in the past 12 months were not advised to quit smoking or talked to about their alcohol use. CONCLUSIONS: Many opportunities to intervene with smokers and binge drinkers are lost. Efforts to increase physician education and to identify and reduce other barriers may help.

Adult↗

PubMed2003

Cancer screening estimates for U.S. metropolitan areas.

OBJECTIVES: To provide estimates of breast, cervical, and colorectal cancer screening for metropolitan areas in the United States. METHODS: Behavioral Risk Factor Surveillance System (BRFSS) data from 1997 to 1999 were reweighted and analyzed for 69 U.S. metropolitan areas for the receipt of a Papanicolaou (Pap) test (ages > or =18 years); mammography (ages > or =40 years); fecal occult blood testing and sigmoidoscopy (ages > or =50 years). Stratified analyses by demographics were performed for 25 metropolitan areas with populations of > or =1.5 million. RESULTS: Metropolitan estimates ranged from 64.6% to 82.0% for mammography and from 77.2% to 91.7% for Pap tests. There was much greater variability in estimates for colorectal cancer screening, with a 3.6-fold difference in the range of estimates for fecal occult blood testing (9.9% to 35.2%) and a 2.5-fold difference for sigmoidoscopy (17.3% to 43.3%). In the 25 largest areas, prevalence of cancer screening was generally lower for persons with a high school education or less and for those without health insurance. Compared with women aged 50 to 64 years, mammography estimates were lower for women aged 40 to 49 years in 13 of the 25 metropolitan areas. Pap testing was less common among women aged > or =65 years, and colorectal cancer screening was less common for persons aged 50 to 64 years. CONCLUSIONS: Estimates of cancer screening varied substantially across metropolitan areas. Increased efforts to improve cancer screening are needed in many urban areas, especially for colorectal cancer screening. The BRFSS is a useful, inexpensive, and timely resource for providing metropolitan-area cancer screening estimates and may be used in the future to guide local or county-level screening efforts.

Adult↗

PubMed2003

A comparison of national estimates from the National Health Interview Survey and the Behavioral Risk Factor Surveillance System.

OBJECTIVES: The purpose of this study was to compare national estimates from the National Health Interview Survey (NHIS) and the Behavioral Risk Factor Surveillance System (BRFSS). METHODS: The authors compared data from the 2 surveys on smoking, height, weight, body mass index, diabetes, hypertension, immunization, lack of insurance coverage, cost as a barrier to medical care, and health status. RESULTS: Overall national estimates were similar for 13 of the 14 measures examined. Small differences according to demographic characteristics were found for height and body mass index, with larger differences for health status. CONCLUSIONS: Although estimates differed within subgroups, the BRFSS provided national estimates comparable to those of the NHIS. BRFSS national data could provide rapidly available information to guide national policy and program decisions.

Adolescent↗

PubMed2002

Contribution of membrane-binding and enzymatic domains of penicillin binding protein 5 to maintenance of uniform cellular morphology of Escherichia coli.

Four low-molecular-weight penicillin binding proteins (LMW PBPs) of Escherichia coli are closely related and have similar DD-carboxypeptidase activities (PBPs 4, 5, and 6 and DacD). However, only one, PBP 5, has a demonstrated physiological function. In its absence, certain mutants of E. coli have altered diameters and lose their uniform outer contour, resulting in morphologically aberrant cells. To determine what differentiates the activities of these LMW PBPs, we constructed fusion proteins combining portions of PBP 5 with fragments of other DD-carboxypeptidases to see which hybrids restored normal morphology to a strain lacking PBP 5. Functional complementation occurred when truncated PBP 5 was combined with the terminal membrane anchor sequences of PBP 6 or DacD. However, complementation was not restored by the putative carboxy-terminal anchor of PBP 4 or by a transmembrane region of the osmosensor protein ProW, even though these hybrids were membrane bound. Site-directed mutagenesis of the carboxy terminus of PBP 5 indicated that complementation required a generalized amphipathic membrane anchor but that no specific residues in this region seemed to be required. A functional fusion protein was produced by combining the N-terminal enzymatic domain of PBP 5 with the C-terminal beta-sheet domain of PBP 6. In contrast, the opposite hybrid of PBP 6 to PBP 5 was not functional. The results suggest that the mode of PBP 5 membrane anchoring is important, that the mechanism entails more than a simple mechanical tethering of the enzyme to the outer face of the inner membrane, and that the physiological differences among the LMW PBPs arise from structural differences in the DD-carboxypeptidase enzymatic core.

Amino Acid Sequence↗

PubMedDate not supplied

Trust and sources of health information: the impact of the Internet and its implications for health care providers: findings from the first Health Information National Trends Survey.

BACKGROUND: The context in which patients consume health information has changed dramatically with diffusion of the Internet, advances in telemedicine, and changes in media health coverage. The objective of this study was to provide nationally representative estimates for health-related uses of the Internet, level of trust in health information sources, and preferences for cancer information sources. METHODS: Data from the Health Information National Trends Survey were used. A total of 6369 persons 18 years or older were studied. The main outcome measures were online health activities, levels of trust, and source preference. RESULTS: Analyses indicated that 63.0% (95% confidence interval [CI], 61.7%-64.3%) of the US adult population in 2003 reported ever going online, with 63.7% (95% CI, 61.7%-65.8%) of the online population having looked for health information for themselves or others at least once in the previous 12 months. Despite newly available communication channels, physicians remained the most highly trusted information source to patients, with 62.4% (95% CI, 60.8%-64.0%) of adults expressing a lot of trust in their physicians. When asked where they preferred going for specific health information, 49.5% (95% CI, 48.1%-50.8%) reported wanting to go to their physicians first. When asked where they actually went, 48.6% (95% CI, 46.1%-51.0%) reported going online first, with only 10.9% (95% CI, 9.5%-12.3%) going to their physicians first. CONCLUSION: The Health Information National Trends Survey data portray a tectonic shift in the ways in which patients consume health and medical information, with more patients looking for information online before talking with their physicians.

Adolescent↗

PubMedDate not supplied

State trends in health risk factors and receipt of clinical preventive services among US adults during the 1990s.

CONTEXT: Monitoring trends is essential for evaluating past activities and guiding current preventive health program and policy efforts. Although tracking progress toward national health goals is helpful, use of national estimates is limited because most preventive health care activities, policies, and other efforts occur at the state or community level. There may be important state trends that are obscured by national data. OBJECTIVE: To estimate state-specific trends for 5 health risk factors and 6 clinical preventive services. DESIGN: Telephone surveys were conducted from 1991 through 2000 as part of the Behavioral Risk Factor Surveillance System. SETTING AND PARTICIPANTS: Randomly selected adults aged 18 years or older from 49 US states. Annual state sample sizes ranged from 1188 to 7543. MAIN OUTCOME MEASURES: Statistically significant changes (P<.01) in state prevalences of cigarette smoking, binge alcohol use, physical inactivity, obesity, safety belt use, and mammography; screening for cervical cancer, colorectal cancer, and cholesterol levels; and receipt of influenza and pneumococcal disease vaccination. RESULTS: There were statistically significant increases in safety belt use for 39 of 47 states and receipt of mammography in the past 2 years for women aged 40 years or older for 43 of 47 states. For persons aged 65 years or older, there were increases in receipt of influenza vaccination for 44 of 49 states and ever receiving pneumococcal vaccination for 48 of 49 states. State trends were mixed for binge alcohol use (increasing in 19 of 47 states and declining in 3), physical inactivity (increasing in 3 of 48 states and declining in 11), and cholesterol screening (increasing in 13 of 47 states and decreasing in 5). Obesity increased in all states and smoking increased in 14 of 47 states (declining only in Minnesota). Cervical cancer screening increased in 8 of 48 states and colorectal cancer screening increased in 13 of 49 states. New York experienced improvements for 8 of 11 measures, while 7 of 11 measures improved in Delaware, Kentucky, and Maryland; in contrast, Alaska experienced improvements for no measures and at least 4 of 11 measures worsened in Iowa, North Dakota, and South Dakota. CONCLUSIONS: Most states experienced increases in safety belt use, mammography, and adult vaccinations. Trends for smoking and binge alcohol use are disturbing, and obesity data support previous findings. Trend data are useful for targeting state preventive health efforts.

Adult↗

PubMedDate not supplied

The Health Information National Trends Survey (HINTS): development, design, and dissemination.

Little is known about access, sources, and trust of cancer-related information, or factors that facilitate or hinder communication on a population-wide basis. Through a careful developmental process involving extensive input from many individuals and organizations, the National Cancer Institute (NCI) developed the Health Information National Trends Survey (HINTS) to help fill this gap. This nationally representative telephone survey of 6,369 persons aged > or = 18 years among the general population was first conducted in 2002-2003, and will be repeated biennially depending on availability of funding. The purpose of creating a population survey to be repeated on a cyclical basis is to track trends in the public's rapidly changing use of new communication technologies while charting progress in meeting health communication goals in terms of the public's knowledge, attitudes, and behaviors. The HINTS survey instrument was built upon extant models of health communication and behavior change, taking into account the rapidly changing communication environment. Questions in the survey were drawn from an overall theoretical framework that juxtaposed the"push" aspects of traditional broadcast media against the"pull" aspects of new media. HINTS data will be made widely available for researchers and practitioners; it will help further research in health communication and health promotion and provide useful information for programs, policies, and practices in a variety of settings.

Access to Information↗