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S Johnson

Publications and source records attributed to S Johnson.

At least 127 records · Page 7Linked to original sources
PubMed2000

Identification of secreted proteins of Mycobacterium tuberculosis by a bioinformatic approach.

Proteins secreted by Mycobacterium tuberculosis are usually targets of immune responses in the infected host. Here we describe a search for secreted proteins that combined the use of bioinformatics and phoA' fusion technology. The 3,924 proteins deduced from the M. tuberculosis genome were analyzed with several computer programs. We identified 52 proteins carrying an NH(2)-terminal secretory signal peptide but lacking additional membrane-anchoring moieties. Of these 52 proteins-the TM1 subgroup-only 7 had been previously reported to be secreted proteins. Our predictions were confirmed in 9 of 10 TM1 genes that were fused to Escherichia coli phoA', a marker of subcellular localization. These findings demonstrate that the systematic computer search described in this work identified secreted proteins of M. tuberculosis with high efficiency and 90% accuracy.

Algorithms↗
PubMed2000

Identification of Mycoplasma fermentans in synovial fluid samples from arthritis patients with inflammatory disease.

Since 1970 Mycoplasma fermentans has been suspected of being associated with rheumatoid arthritis. However, this association has been difficult to prove, and this has been our goal. The distribution of M. fermentans was studied in the synovial fluid of patients suffering from different arthritides. Samples of synovial fluid were taken from patients with well-defined disease and a clear diagnosis. After removal of the inflammatory cells and hyaluran, they were treated with proteinase K and tested by a single or fully nested PCR with primers directed against part of the two 16S rRNA genes of M. fermentans. The product was sequenced automatically, by using an ALF Express automatic sequencer, to confirm the mycoplasma species and to identify the strain since the two genes were usually found to be polymorphic. This was also true of the type strain, strain PG18. M. fermentans was detected in 23 of 26 (88%) rheumatoid arthritis patients, and four different strains were found. It was also found in 7 of 8 (88%) of the nonrheumatoid inflammatory arthritis patient group, which consisted of one patient with reactive arthritis, one patient with pauciarticular juvenile chronic arthritis, two patients with gout, two patients with ankylosing spondylitis, and two patients with psoriatic arthritis, only one of whom was infected with M. fermentans. It was not detected in any of the 10 osteoarthritis patients. M. fermentans was therefore found to be a variable and very common organism in arthritic patients with inflammatory joint exudates and may well prove to be important in the etiology of the diseases.

Adult↗
PubMed2000

Prevalence of SIDS risk factors: before and after the "Back to Sleep" campaign in North Dakota Caucasian and American Indian infants.

The objective of this study was to compare rates of infant sleeping position and other risk factors for sudden infant death syndrome from 1991 before the "Back to Sleep" campaign to rates in 1998 after the campaign. We used a cross-sectional risk factor prevalence study of risk factors for the years 1991 and 1998. In North Dakota the prevalence rates of prone sleeping declined 72% for American Indian infants and 62% for Caucasian infants. We were unable to identify a corresponding decline in SIDS in North Dakota for this time period. The relationship between sleeping position and SIDS may be more complex in rural and frontier settings and in American Indian populations than in urban and majority populations. The generalizability of this study is limited by the rural setting and small sample size. Longer term surveillance and additional reports from sites with pre "Back to Sleep" data as a baseline for both SIDS rates and sleeping position will be important to clarify the rate of prone sleeping position and SIDS.

Cross-Sectional Studies↗
PubMed2000

Placental growth hormone (GH), GH-binding protein, and insulin-like growth factor axis in normal, growth-retarded, and diabetic pregnancies: correlations with fetal growth.

We previously described significant changes in GH-binding protein (GHBP) in pathological human pregnancy. There was a substantial elevation of GHBP in cases ofnoninsulin-dependent diabetes mellitus and a reduction in insulin-dependent diabetes mellitus. GHBP has the potential to modulate the proportion of free placental GH (PGH) and hence the impact on the maternal GH/insulin-like growth factor I (IGF-I) axis, fetal growth, and maternal glycemic status. The present study was undertaken to investigate the relationship among glycemia, GHBP, and PGH during pregnancy and to assess the impact of GHBP on the concentration of free PGH. We have extended the analysis of specimens to include measurements of GHBP, PGH, IGF-I, IGF-II, IGF-binding protein-1 (IGFBP-1), IGFBP-2, and IGFBP-3 and have related these to maternal characteristics, fetal growth, and glycemia. The simultaneous measurement of GHBP and PGH has for the first time allowed calculation of the free component of PGH and correlation of the free component to indexes of fetal growth and other endocrine markers. PGH, free PGH, IGF-I, and IGF-II were substantially decreased in IUGR at 28-30 weeks gestation (K28) and 36-38 weeks gestation (K36). The mean concentration (+/-SEM) of total PGH increased significantly from K28 to K36 (30.0 +/- 2.2 to 50.7 +/- 6.2 ng/mL; n = 40), as did the concentration of free PGH (23.4 +/- 2.3 to 43.7 +/- 6.0 ng/mL; n = 38). The mean percentage of free PGH was significantly less in IUGR than in normal subjects (67% vs. 79%; P < 0.01). Macrosomia was associated with an increase in these parameters that did not reach statistical significance. Multiple regression analysis revealed that PGH/IGF-I and IGFBP-3 account for 40% of the variance in birth weight. IGFBP-3 showed a significant correlation with IGF-I, IGF-II, and free and total PGH at K28 and K36. Noninsulin-dependent diabetes mellitus patients had a lower mean percentage of free PGH (65%; P < 0.01), and insulin-dependent diabetics had a higher mean percentage of free PGH (87%; P < 0.01) than normal subjects. Mean postprandial glucose at K28 correlated positively with PGH and free PGH (consistent with the hyperglycemic action of GH). GHBP correlated negatively with both postprandial and fasting glucose. Although GHBP correlated negatively with PGH (r = -0.52; P < .001), free PGH and total PGH correlated very closely (r = 0.98). The results are consistent with an inhibitory function for GHBP in vivo and support a critical role for placental GH and IGF-I in driving normal fetal growth.

Adult↗
PubMed2000

Microsatellite alterations plasma DNA of primary breast cancer patients.

The aim of this study was to analyze plasma DNA from primary and metastatic breast cancer cases for tumor-specific alterations and to compare these findings with immunocytochemistry and estimation of cytokeratin 19 (CK19) mRNA for detection of micrometastases. DNA was extracted from plasma, lymphocytes, and microdissected tumor tissue sections obtained from 71 patients with breast cancer and 9 controls. DNA samples were analyzed for loss of heterozygosity (LOH) and/or microsatellite instability (MI) by PCR with two polymorphic markers (DM-1 and D16S400). Reverse transcription-quantitative PCR (QPCR) and immunocytochemistry were used for detection of CK19 mRNA and protein. Breast cancer plasma DNA displayed frequent LOH (31.3%) and MI (11.6%) supported by the same alteration in microdissected tumor DNA. Most notably, 10 of the 39 patients with primary breast cancer showed LOH (n = 6) or MI (n = 4). We compared plasma tumor DNA, plasma and bone marrow QPCR, and blood and bone marrow immunocytochemistry in 32 of the patients with primary cancer. Of these, only one patient had immunocytochemically detectable carcinoma cells in the blood, and three showed abnormally high levels of plasma CK19 mRNA. All four of these patients had plasma DNA alterations. We then compared bone marrow findings: of the 10 primary breast cancers that showed LOH or MI, 6 had elevated CK19 mRNA and 5 had immunocytochemically positive cells. Tumor DNA is readily detectable in plasma of primary and metastatic breast cancer patients, and plasma DNA alterations (LOH and MI) reflect those seen in the tumor. The application of microsatellite analyses to plasma DNA may be useful in assessing tumor burden in breast cancer patients, particularly when combined with QPCR, and is preferable for patients with breast cancer, for whom sequential bone marrow aspiration is undesirable.

Adult↗
PubMed2000

Comparison of Florida Hispanic and non-Hispanic Caucasian women in their health beliefs related to breast cancer and health locus of control.

PURPOSE/OBJECTIVES: To compare Florida Hispanic and non-Hispanic Caucasian women in their health beliefs about breast cancer and health locus of control (LOC). DESIGN: Exploratory, comparative. SETTING: A variety of healthcare settings in an urban area in Florida. SAMPLE: Hispanic (n = 113) and non-Hispanic (n = 197) Caucasian women who could read and understand either English or Spanish. METHODS: The Health Screening Questionnaire, which assesses health beliefs and health LOC, was administered in either Spanish or English, and the results were analyzed. MAIN RESEARCH VARIABLES: Attitudes about health in general, perceptions about susceptibility to cancer, beliefs about benefits of early diagnosis, and perceptions about the seriousness of cancer; LOC. FINDINGS: Florida Hispanic women are better educated than the Mexican American Hispanic women described in the literature. Hispanic and non-Hispanic women were significantly different in their health beliefs and LOC. With age and education controlled statistically, these differences remained. Hispanic women who preferred to speak/read English were more like the non-Hispanic women in their responses than were the women who preferred Spanish. CONCLUSIONS: Cultural differences exist between Hispanic and non-Hispanic women; however, differences also exist between groups of Hispanic women in Florida versus Hispanics in the southwestern United States. IMPLICATIONS FOR NURSING PRACTICE: Outreach programs for cancer screening should be culturally relevant and may need to be different for subgroups of Hispanics in the United States.

Age Factors↗
PubMed2000

Generic data modeling for home telemonitoring of chronically ill patients.

Management of many types of chronic diseases such as diabetes and asthma relies heavily on patients' self-monitoring of their disease conditions. In recent years, internet-based home telemonitoring systems that allow transmission of patient data to a central database and offer immediate access to the data by the care providers have become available. However, these systems often work with only one or a few types of medical devices and thus are limited in the types of diseases they can monitor. For example, a system designed to collect spirometry data from asthmatic patients cannot be easily adapted to collect blood glucose data from diabetic patients. This is because different medical devices produce different types of data and the existing telemonitoring systems are generally built around a proprietary data schema specific for the device used. In this paper, we describe a generic data schema for a telemonitoring system that is applicable to different types of medical devices and different diseases, and show an implementation of the schema in a relational database suitable for a variety of telemonitoring activities.

Asthma↗
PubMed2000

The European Service Mapping Schedule (ESMS): development of an instrument for the description and classification of mental health services.

OBJECTIVE: This paper describes the development of an instrument for description and classification of mental health services and for measurement of service use. Purposes to be served by the instrument include: (i) identification of gaps in the spectrum of services in a catchment area; (ii) obtaining background information which may be important to understanding why apparently similar interventions lead to different outcomes in different areas; (iii) investigating how introduction of a particular type of service influences use of other local services; and (iv) understanding the relationship between sociodemographic factors and service use. METHOD: The instrument was developed through meetings of an international expert panel and pilot stages in several European countries. RESULTS: Use of the European Mapping Service Mapping Schedule (ESMS) appears feasible in several countries and allowed description and classification of the full range of services identified within each of the study catchment areas. CONCLUSION: The ESMS promises to fill a gap in the technology available for mental health services research. Further practical experiences of its use for a variety of purposes in a variety of settings are now needed to indicate how far the ESMS does successfully generate data which are useful to researchers and planners.

Europe↗
PubMed2000

Assessment instruments: standardization of the European Service Mapping Schedule (ESMS) in Spain.

OBJECTIVE: To adapt the European Service Mapping Schedule (ESMS) for use in Spain and assess the quality of this schedule. METHOD: Following linguistic and conceptual translation, 77 services in five Spanish catchment areas were described by independent local raters, including two experts in health services research. Feasibility (applicability. acceptability and practicality), descriptive validity and overall percentage agreement were assessed. RESULTS: ESMS feasibility was considered adequate. The tree system facilitates reporting and comparison of data. Face, content and discriminant validity are adequate for almost all services. The overall reliability was high but completion of the service utilization section required expert supervision. The ESMS revealed large differences in service availability and utilization in the five different areas of Spain. CONCLUSION: The ESMS has proved useful for describing mental health services in Spain, and facilitates comparisons between catchment areas.

Cultural Characteristics↗
PubMed2000

The European Socio-Demographic Schedule (ESDS): rationale, principles and development.

OBJECTIVE: To design an internationally valid and practical instrument on which data can be recorded for small areas that describes the sociodemographic characteristics known to be associated with psychiatric morbidity and service use. METHOD: (1) Identification of a set of sociodemographic characteristics which, on the basis of currently available evidence, would be expected to influence needs for and provision of mental health care in different countries. (2) Selection of a subset of these for inclusion in the schedule based on likely degree of cross-cultural validity and on the types and formats of the data routinely available in each country. (3) Revision of the schedule following a pilot by EPCAT members. RESULTS: The European Socio-Demographic Schedule (ESDS) was successfully employed to collect sociodemographic data in seven catchment areas. Differences were found between the areas in terms of availability of data as well as in the resulting profiles. CONCLUSION: The ESDS has been shown to be applicable in a number of European countries.

Adolescent↗
PubMed2000

New challenge for states: Indian health care.

Devolution has given states a role in making sure Indian tribes have adequate health care. Along with these new opportunities comes greater responsibility--for both states and tribes.

Child↗
PubMed2000

Factors influencing the success of ICP projects.

In order to evaluate ICPs, criteria for success must be identified. The key areas to consider are quality of patient care, staff and patient satisfaction, documentation and cost. Commitment, resources, desire and need, facilitation and management also have an impact. The role of the ICP facilitator is vital to a project's success.

Critical Pathways↗
PubMed2000

Setting standards using integrated care pathways.

An integrated care pathway is a tool that can help to deliver clinical governance objectives if implemented well. Key factors of successful implementation are: effective project management; communication and training; and top-down and bottom-up support for the process.

Critical Pathways↗