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PubMed1997

Characterisation of Neisseria gonorrhoeae in semen during urethral infection in men.

OBJECTIVE: To determine the number of Neisseria gonorrhoeae organisms in urine and semen in men with gonococcal urethritis, and to compare selected phenotypic characteristics of organisms harvested from the urethra and semen. DESIGN: Samples from two groups of subjects were examined. Patients with symptomatic urethritis receiving treatment at an STD clinic, as well as six subjects with experimental urethritis. Semen and urine specimens were obtained after the urethral exudate was sampled. RESULTS: Using quantitative cultures, we found an average of 6 x 10(6) gonococci in urine or semen of 17 men with symptomatic urethritis seeking treatment at an STD clinic, and 2 x 10(4) gonococci in secretions of six male subjects with early experimental infection. Gonococcal outer membrane opacity (Opa) proteins and lipo-oligosaccharide (LOS) recovered from urine and semen of these subjects were very similar. CONCLUSIONS: Men with symptomatic gonorrhoea excrete a large number of gonococci in semen which is not affected by the duration of symptoms. The similar phenotype of organisms in urine and semen suggests the bacteria come from the same compartment. These data help to explain the efficiency of gonococcal transmission from men to their partners, and identify an appropriate target for a preventative vaccine or immunotherapy designed to reduce the inoculum in infected patients.

Adolescent↗
PubMed2005

Effect of a second-generation venous catheter impregnated with chlorhexidine and silver sulfadiazine on central catheter-related infections: a randomized, controlled trial.

BACKGROUND: Central venous catheter-related infections are a significant medical problem. Improved preventive measures are needed. OBJECTIVE: To ascertain 1) effectiveness of a second-generation antiseptic-coated catheter in the prevention of microbial colonization and infection; 2) safety and tolerability of this device; 3) microbiology of infected catheters; and 4) propensity for the development of antiseptic resistance. DESIGN: Multicenter, randomized, double-blind, controlled trial. SETTING: 9 university-affiliated medical centers. PATIENTS: 780 patients in intensive care units who required central venous catheterization. INTERVENTION: Patients received either a standard catheter or a catheter coated with chlorhexidine and silver sulfadiazine. MEASUREMENTS: The authors assessed catheter colonization and catheter-related infection, characterized microbes by molecular typing, and determined their susceptibility to antiseptics. Patient tolerance of the catheter was monitored. RESULTS: Patients with the 2 types of catheters had similar demographic features, clinical interventions, laboratory values, and risk factors for infection. Antiseptic catheters were less likely to be colonized at the time of removal compared with control catheters (13.3 vs. 24.1 colonized catheters per 1000 catheter-days; P < 0.01). The center-stratified Cox regression hazard ratio for colonization controlling for sampling design and potentially confounding variables was 0.45 (95% CI, 0.25 to 0.78). The rate of definitive catheter-related bloodstream infection was 1.24 per 1000 catheter-days (CI, 0.26 to 3.62 per 1000 catheter-days) for the control group versus 0.42 per 1000 catheter-days (CI, 0.01 to 2.34 per 1000 catheter-days) for the antiseptic catheter group (P = 0.6). Coagulase-negative staphylococci and other gram-positive organisms were the most frequent microbes to colonize catheters. Noninfectious adverse events were similar in both groups. Antiseptic susceptibility was similar for microbes recovered from either group. LIMITATIONS: The antiseptic catheter was not compared with an antibiotic-coated catheter, and no conclusion can be made regarding its effect on bloodstream infection. CONCLUSIONS: The second-generation chlorhexidine-silver sulfadiazine catheter is well tolerated. Antiseptic coating appears to reduce microbial colonization of the catheter compared with an uncoated catheter.

Aged↗
PubMed1989

AIDS: methodological problems in studying its prevention and spread.

This paper outlines some problems in conducting AIDS research in developing countries, discusses the impact of the socio-cultural setting on study efforts, and emphasizes the need for adopting methodological approaches that are highly sensitive to the environment. The importance of seeing AIDS as a disease that affects humans not merely biologically, but also socially--in terms of their conceptions of sexual behavior and their belief systems of disease, illness and sickness--is considered. The potential of scientists to disregard this facet in the study of AIDS is stressed. The imperatives for interdisciplinary collaboration between the medical and social scientists are examined to argue that without combining research agendas, significant variables will be ignored in the search for ways to control AIDS. Special attention is given to the limitations of several methods that are employed by medical and social science researchers, including research designs, sampling, data collection and analysis, to suggest that with AIDS research these may be difficult to operationalize. The ethical implications of some of these are weighed. The interaction of economic and political conditions of the context with research activity is explored. Suggestions are given which take cognizance of the fact that it is human beings and Third World conditions, as well as the complexities of HIV and AIDS, that make AIDS research so problematic.

Acquired Immunodeficiency Syndrome↗
PubMed2002

Utilization of complementary and alternative medicine by United States adults: results from the 1999 national health interview survey.

OBJECTIVE: To measure utilization of complementary and alternative medicine (CAM) by US adults. METHODS: We analyzed data from the 1999 National Health Interview Survey (NHIS), which covers the noninstitutionalized civilian US population. Information on 12 types of CAM use in the past 12 months was obtained from 30,801 respondents aged 18 years and older. Statistical analyses were performed using the SUDAAN software package to account for the complex sample design of the NHIS. RESULTS: An estimated 28.9% of US adults used at least one CAM therapy in the past year. The three most commonly used therapies were spiritual healing or prayer (13.7%), herbal medicine (9.6%), and chiropractic therapies (7.6%). The use of CAM was most prevalent among women, persons aged 35 to 54 years, and persons with an educational attainment of > or =16 years. The overall CAM use was higher for white non-Hispanic persons (30.8%) than for Hispanic (19.9%) and black non-Hispanic persons (24.1%). Although the use was higher for persons who had health insurance than for those who did not, the difference was not statistically significant after adjusting for age, gender and educational attainment. Compared with nonusers, CAM users were more likely to use conventional medical services. CONCLUSIONS: Estimates of CAM use in this nationally representative sample were considerably lower than have been reported in previous surveys. Most CAM therapies are used by US adults in conjunction with conventional medical services.

Adolescent↗
PubMed1996

An efficient method for the rescue and analysis of functional HIV-1 env genes: evidence for recombination in the vicinity of the tat/rev splice site.

OBJECTIVE: To establish a robust procedure for the isolation and characterization of full-length expression-competent HIV-1 env genes directly from patient samples. DESIGN: HIV exists as a quasispecies which can be disturbed by in vitro culture, in which numerous members of the population are likely to be defective due to the high error rate of the viral reverse transcriptase. Defective viruses are unlikely to play a dominant role in disease progression. Since env gene translation products play major roles in the initiation and spread of infection we need to study genes with open reading frames. METHODS: A nested polymerase chain reaction (PCR) approach has been used to rescue intact (2.6 kb) env genes, which are cloned into a T7-promoter-containing vector. Expression of gp160 in CV-1 cells is detected by Western blot. Expression-competent clones are sequenced and resulting sequences used for phylogenetic studies. Translation products are analysed in relation to the known immunogenic structure of gp160. RESULTS: From random patient samples collected in London clinics, only HIV-1 subtype B was found. Two of the samples contained viruses with an additional pair of cysteine residues in their V1 regions. For samples collected in Uganda, HIV-1 subtypes A, D and an A/D recombinant were recovered. CONCLUSION: An effective procedure is described for the isolation of HIV-1 env genes directly from patient samples, which has worked for A, B and D subtypes to date. The PCR primers can be utilized with other subtypes with the possible exception of subtype O viruses. Phylogenetic analyses revealed the potential importance of a G/C-rich region near the tat/rev splice site as a site of recombination. The sequences and translation products generated may be more relevant to disease progression in vivo and vaccine formulations than those obtained from viruses selected in long-term culture.

Base Sequence↗
PubMed2003

Individual determinants of research utilization: a systematic review.

CONTEXT: In order to design interventions that increase research use in nursing, it is necessary to have an understanding of what influences research use. OBJECTIVE: To report findings on a systematic review of studies that examine individual characteristics of nurses and how they influence the utilization of research. SEARCH STRATEGY: A survey of published articles in English that examine the influence of individual factors on the research utilization behaviour of nurses, without restriction of the study design, from selected computerized databases and hand searches. INCLUSION CRITERIA: Articles had to measure one or more individual determinants of research utilization, measure the dependent variable (research utilization), and evaluate the relationship between the dependent and independent variables. The studies also had to indicate the direction of the relationship between the independent and dependent variables, report a P-value and the statistic used, and indicate the magnitude of the relationship. RESULTS: Six categories of potential individual determinants were identified: beliefs and attitudes, involvement in research activities, information seeking, professional characteristics, education and other socio-economic factors. Research design, sampling, measurement, and statistical analysis were examined to evaluate methodological quality. Methodological problems surfaced in all of the studies and, apart from attitude to research, there was little to suggest that any potential individual determinant influences research use. CONCLUSION: Important conceptual and measurement issues with regard to research utilization could be better addressed if research in the area were undertaken longitudinally by multi-disciplinary teams of researchers.

Attitude of Health Personnel↗
PubMedDate not supplied

Lessons from an evaluation of the effectiveness of an asthma day camp.

PURPOSE: To evaluate the effectiveness of applied teaching methodologies in a camp setting on asthma self-management skills in school-age children. DESIGN: This was a descriptive pilot study using a one-group pretest-posttest design. SAMPLE: Thirty-four subjects, ages 6 to 12 years, representing a typical clinical population of children with asthma. METHODS: Children's asthma knowledge, symptoms, behavior, and mastery, as well as peak-flow technique, were measured 2 to 3 weeks before camp and then again on the last day of camp. Baseline measures of parents' asthma knowledge and family stress related to asthma were obtained. Outcomes specific to asthma management, such as missed school days, emergency room visits, and hospitalizations, were evaluated by parent report the year before and after the intervention. RESULTS: Significant improvement in peak-flow technique and a reported reduction in emergency room visits and missed school days after camp were found. CLINICAL IMPLICATIONS: In this pilot study, the use of an applied teaching format for school-age children in an asthma day camp resulted in some learning. More rigorous design and instrumentation are important for better evaluation of programs such as this. Nurses working with these populations should plan structured evaluations of the programs so they can best meet the children's needs.

Asthma↗
PubMed2005

Conducting research on violence in Asian American communities: methodological issues.

Conducting culturally competent research is a challenge as the United States becomes increasingly multicultural. When conducting research on violence in Asian American communities, researchers need to consider how culture, race, and ethnicity influence definitions of concepts, and methodological issues such as research designs, sampling, developing and translating instruments, ethical issues, recruiting research participants, supervising and training interviewers, and disseminating findings. Examples from the authors' research studies on community violence in the Khmer community, domestic violence in the Chinese American community, and dating violence in Asian American groups are extrapolated to highlight various themes. A commitment to a research program that collaborates with the community under study and cultural experts is vital at every stage of the research process.

Adolescent↗
PubMed2006

Preanalytical aspects of quantitative TaqMan real-time RT-PCR: applications for TF and VEGF mRNA quantification.

OBJECTIVES: The present paper focuses on preanalytical aspects of tissue factor (TF) and vascular endothelial growth factor (VEGF) mRNA quantification: the choice of blood collection tubes and defining the time frame allowed before processing the sample. DESIGN AND METHODS: Blood was collected from healthy volunteers in K(3) EDTA tubes, CPT, endotoxin-free EndoTube tubes and in PAXgene tubes. Total RNA concentration was determined by absorbance readings at 260 nm with a GeneQuantII UV spectrophotometer. RNA quantity and quality were also determined by the Lab on a Chip technique (Agilent 2100 Bioanalyzer). Real-time RT-PCR assays were performed by the TaqMan technology. RESULTS: The more expensive PAXgene and CPT tubes and the Endo tubes did not give superior results from those obtained in inexpensive routine K(3) EDTA tubes. The PAXgene tubes preserved high molecular mass rRNA better than the other tubes. CONCLUSION: Both the PAXgene system and routine EDTA tubes are suitable for clinical purposes aimed at quantitation of mRNA for TF and VEGF. PAXgene yielded rRNA that was less degraded but had lower mRNA per microg extracted RNA. A time frame up to 24 h until sample processing is acceptable for TF and VEGF mRNA.

DNA, Complementary↗
PubMedDate not supplied

Sensitivity of radiographic evaluation of radio-ulnar incongruence in the dog in vitro.

OBJECTIVE: To determine the sensitivity and specificity of radiographic evaluation of radio-ulnar incongruence in canine elbow joints in vitro. STUDY DESIGN: Radiographic evaluation of induced radio-ulnar incongruence in canine cadaveric forelimbs by radiologists blinded to study design. SAMPLE POPULATION: Six cadaveric canine left forelimbs. METHODS: Extended lateral, 90 degrees flexed lateral, and cranio-caudal projections were taken of the elbow joint of six cadaveric canine forelimbs. A four-pin, type I external skeletal fixator (ESF) with a linear motor side bar was attached to the medial aspect of the radius, and a 2-cm segment of bone was removed from the mid-diaphysis. A 3.5-mm cortical bone screw placed from the medial to lateral styloid processes prevented relative movement between the distal radius and ulna during radial shortening. The ESF was used to progressively shorten the radius in increments of 0.5 mm to a total of 4 mm. The three radiographic projections were repeated after each incremental change of length. After the study, each elbow joint was disarticulated to confirm the presence of a step defect. The original radiographs and three copies were randomized and then evaluated by four radiologists blinded to the study design. Radiologists were asked to evaluate whether the joint was normal or abnormal and if there was evidence of radio-ulnar incongruence. The ability of each radiologist to correctly identify congruent elbows (specificity) and incongruent elbows (sensitivity) was calculated. RESULTS: The median specificity was 86% using the lateral projection and 82% using the cranio-caudal projection. The median sensitivities using the lateral and cranio-caudal radiographic projections were 78% and 79%, respectively. The degree of radial shortening required for individual radiologists to achieve a sensitivity of 90% ranged from 1.5 mm to greater than 4 mm. CLINICAL RELEVANCE: Standard radiographic evaluation for radio-ulnar incongruence in the dog may be associated with relatively poor sensitivity and specificity. Invasive surgical procedures and screening programs that rely on radiographic diagnosis of radio-ulnar incongruence should be discouraged until a more reliable method of diagnosis of this type of elbow joint incongruence is available.

Animals↗
PubMed1986

Testing for familial aggregation of a dichotomous trait.

Familial aggregation of a disease is usually tested using a chi square statistic on a sample of pairs of related individuals. Standard sampling designs often produce dependent observations (multiple pairs from the same family), possibly inflating the numerical value of the statistic over the value independent observations would produce. This article presents a derivation of the chi square statistic for familial aggregation, allowing for dependency because of the inclusion of the same and related persons in multiple pairs. For intraclass aggregation, the standard chi square statistic is appropriate. For interclass aggregation, an adjustment to the standard chi square statistic is needed; the adjustment depends on the disease frequency and the intraclass aggregation within each class.

Analysis of Variance↗
PubMed1999

Prevalence of the metabolic syndrome in drug-treated hypertensive patients and control subjects.

OBJECTIVES: To determine the prevalence of the metabolic abnormalities associated with hypertension and to define the predictors of the metabolic syndrome by different definitions in random population-based samples. DESIGN: A cross-sectional epidemiological study of hypertensive patients and controls. SETTING: The participating study subjects visited the research laboratory of the Department of Internal Medicine, University of Oulu, Oulu, Finland. SUBJECTS: Six hundred treated male and female hypertensives aged 40-59 years and 600 age- and sex-matched controls were randomly selected by age stratification from population registers. MAIN OUTCOME MEASURES: A wide range of laboratory analyses were conducted. After fasting blood had been drawn, the subjects were given a 75 g glucose load except previously known insulin-treated diabetics. Both 1 h and 2 h glucose and insulin concentrations were determined. During the same visit, a standardized health questionnaire covering the past medical history, current and former medication use, physical activity, smoking habits, alcohol consumption and family history was completed. Ten different definitions of the metabolic syndrome were applied to achieve a wide perspective of the prevalence of the different combinations. RESULTS: The prevalence of the metabolic syndrome in different samples varied depending on the definition from 0.8 to 35.3%, being lowest in the control men and women and highest in the hypertensive men. Three-quarters of a random, middle-aged, urban population show at least one cardiovascular risk factor and 91.3% of all the hypertensive subjects show at least one cardiovascular risk factor in addition to hypertension itself. The independent predictors of the metabolic syndrome were waist circumference, uric acid, total cholesterol and gamma-glutamyl transpeptidase in logistic analysis after adjustment for age, measure of obesity and gender. CONCLUSIONS: This cross-sectional, epidemiological study shows that the magnitude of the prevalence rates of the metabolic syndrome is at the same level in various populations, being less than one-third in population-based samples in spite of the different definitions. The cluster of several cardiovascular risk factors, especially in the hypertensives, leads to an increased relative risk of cardiovascular diseases.

Adult↗
PubMed2000

The association between cigarette smoking and drug abuse in the United States.

Cigarette smoking has been identified as an independent risk factor for many human diseases. However, the association between cigarette smoking and illegal drug use has not been thoroughly investigated. We have analyzed the 1994 National Household Survey on Drug Abuse to clarify whether cigarette smoking has any effect on the initiation of illegal drug use. Data from 17,809 respondents completing the 1994 "new" (1994-B) questionnaire were analyzed. Logistic regression analyses were performed with the use of statistical package SUDAAN, taking into consideration the multistage sampling design. The results show that those who had smoked cigarettes were far more likely to use cocaine (OR = 7.5; 95% CI: 5.7-9.9), heroin (OR = 16.0; 95% CI: 6.8-37.9), crack (OR = 13.9; 95% CI: 7.9-24.5) and marijuana (OR = 7.3; 95% CI: 6.2-8.7). The associations are consistent across age-strata and remain after adjusting for race and gender. This study suggests that cigarette smoking may be a gateway drug to illegal drug use.

Adolescent↗
PubMed1989

Condom use and acceptance: a survey of male Zimbabweans.

In addition to their traditional contraceptive role, condoms have moved to a crucial and central position in the strategy for prevention of sexual transmission of the human immunodeficiency virus (HIV) and other sexually transmitted diseases (STDs). As a cure for AIDS remains out of sight, condom use, celibacy and extensive health education remain the immediate sole weapons for controlling HIV infection. A stratified cluster sampling design of 722 Zimbabwean men reported 35.7 percent ever use of condoms while only 4.9 percent reported current condom use. 32.4 percent had unprompted knowledge of condom use for contraception. Circumstances during which condoms were used are discussed. Asked if the men would use condoms if asked by either wife or partner, only 30.0 percent of men who had not previously used condoms indicated that they would. Reasons given by the 64 percent with no previous use of condoms are discussed. Health education to promote acceptance and use of condoms is proposed.

Acquired Immunodeficiency Syndrome↗
PubMed2005

Self-monitoring and pelvic floor muscle exercises to treat urinary incontinence.

Urinary incontinence (UI) is a common chronic condition among women. Treatment of UI can involve behavioral techniques, pharmacological strategies, or surgical intervention. Clinically, treatment strategies should start with the simplest and least invasive measures. To overcome the deficiencies in previous research and provide definitive information for clinical practice, a randomized clinical trial is currently underway. This clinical trial uses a pretest-posttest design to first determine the effectiveness of self-monitoring techniques before subjects are randomized into one of two treatment groups or an attentional control group with a 1-year followup. The study design, sampling plan, and interventions used in an ongoing clinical trial to assess the effectiveness of self-monitoring and efficacy of biofeedback to treat UI in women are described. Innovative techniques to assess adherence to the pelvic muscle exercise protocol are addressed.

Adult↗
PubMed1998

Differences in fatigue by treatment methods in women with breast cancer.

PURPOSE/OBJECTIVES: To investigate the differences between various cancer therapies (radiation, hormonal, chemotherapy, and their combinations) and the specific dimensions of fatigue (affective meaning, behavioral/severity, cognitive/mood, and sensory). DESIGN: Descriptive, cross-sectional, mailed survey design. SAMPLE AND SETTING: Data were collected from women who were breast cancer survivors and members of a nonprofit educational organization in the North-east. Criteria for this study included no self-reported disease recurrence, and treatment was within 18 months prior to the mailed survey (N = 322). The typical participant was middle-aged (mean = 52.2; SD = 10.3), Caucasian (93%), postmenopausal (55%), and diagnosed with cancer 2.42 (SD = 2.6) years prior to the study. METHODS: Secondary data analysis from a study using the Piper Fatigue Scale. VARIABLES: Level of fatigue. FINDINGS: Significant differences were found by treatment in total fatigue scores (p < 0.03) and cognitive/mood scores (p < 0.05). Women who received combination therapy had the highest fatigue scores (mean = 4.8; SD = 2.0); those who received only radiation therapy had the lowest fatigue scores (mean = 2.7; SD = 2.0). CONCLUSIONS: Fatigue in breast cancer survivors varies by type of cancer therapy. Future studies are needed to investigate the relationships between fatigue and hormonal therapy, and they need to be designed to examine changes over time. IMPLICATIONS FOR NURSING PRACTICE: Study findings advance knowledge about fatigue in women with breast cancer and aid nurses in providing anticipatory guidance for women undergoing different treatment regimens.

Adult↗
PubMed1996

Rapid and sensitive detection of Shigella sonnei in feces by the use of an O-antigen-specific monoclonal antibody in a combined immunomagnetic separation-polymerase chain reaction assay.

OBJECTIVE: The aim of the present work was to develop a rapid, specific and highly sensitive diagnostic method for the detection of Shigella sonnei directly from stool samples. DESIGN AND METHODS: An immunomagnetic separation-polymerase chain reaction (IMS-PCR) combined assay for diagnosis of S. sonnei was developed. For this, a monoclonal antibody (Mab) specific for the O-antigen of S. sonnei was coated to magnetic beads for capture, concentration and separation of S. sonnei from feces. Bacterial DNA, was amplified by the PCR with specific primers. The amplified products were developed by dot blot hybridization with a specific alkaline phosphatase-conjugated probe. RESULTS: The purified MASS MAb reacted specifically with the Plesiomonas shigelloides (the same O-antigen as Shigella sonnei) LPS. The primers were specific for invasive Shigella and enteroinvasive Escherichia coli. Only invasive Shigella sonnei strains gave a positive result in the IMS-PCR assay. The detection limit was 10 to 15 c.f.u. CONCLUSIONS: The availability of IMS-PCR assays provides an improved method for the diagnosis of shigellae directly from feces. The assay is rapid, highly sensitive and specific for the detection of Shigella sonnei directly from stool samples.

Journal Article↗
PubMed1998

Rates of intimate partner violence in the United States.

OBJECTIVES: Estimates of intimate partner violence in the United States based on representative samples have relied on data from one person per household or limited numbers of indicators from both partners. The purpose of this study was to estimate nationwide rates of intimate partner violence with data from both couple members by using a standardized survey instrument, the Conflict Tactics Scale. METHODS: A multistage probability sampling design was used to conduct separate face-to-face interviews in respondents' homes with both members of 1635 representative couples living in the 48 contiguous states. RESULTS: Both partners' reports were used to estimate the following lower- and upper-bound rates: 5.21% and 13.61% for male-to-female partner violence, 6.22% and 18.21% for female-to-male partner violence, and 7.84% to 21.48% for any partner-to-partner violence. CONCLUSIONS: High rates of intimate partner violence in the United States corroborate previous claims that the amount of intimate partner violence is substantial.

Adult↗