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PubMed1985

Isolated systolic hypertension in 14 communities.

In the Hypertension Detection and Follow-up Program, 158,906 individuals from 14 communities around the United States had their blood pressure measured in their homes in 1972-1973. Of the total population screened, 2.4% had isolated systolic hypertension (systolic blood pressure greater than or equal to 160 mmHg and diastolic blood pressure less than 90 mmHg). Isolated systolic hypertension was present for 0.5% of those aged 30-39 years and 6.8% among those aged 60-69 years. The prevalence in blacks and women was greater than the prevalences in both whites and men. The prevalence among those taking antihypertensive medications at the time of screening was 6.1%, and 1.9% among those not on antihypertensive medications. From the individuals with "normal" diastolic blood pressure on the single home measurement (less than 90 mmHg), a random sample of 5,032 individuals were followed for mortality for eight years. Prevalence of isolated systolic hypertension was similar in this sample to that in the total. Among those not on antihypertensive medications, 8-year life table all-cause mortality rates adjusted for age, race, and sex were 17.6% for those with systolic blood pressure greater than or equal to 160 mmHg and 7.7% for those with systolic blood pressure greater than 160 mmHg. Among this population, all of whom had a diastolic blood pressure less than 90 mmHg, a multiple logistic analysis adjusting for baseline treatment status, age, race, sex, education, smoking, weight, pulse, physical activity, and systolic blood pressure revealed that each millimeter increase in systolic blood pressure was associated with approximately a 1% increase in mortality over the eight years of follow-up (p less than 0.05). Isolated systolic hypertension is both relatively common and a significant risk factor for subsequent mortality.

Actuarial Analysis↗

PubMed2005

Clustered local transmission and asymptomatic Plasmodium falciparum and Plasmodium vivax malaria infections in a recently emerged, hypoendemic Peruvian Amazon community.

BACKGROUND: There is a low incidence of malaria in Iquitos, Peru, suburbs detected by passive case-detection. This low incidence might be attributable to infections clustered in some households/regions and/or undetected asymptomatic infections. METHODS: Passive case-detection (PCD) during the malaria season (February-July) and an active case-detection (ACD) community-wide survey (March) surveyed 1,907 persons. Each month, April-July, 100-metre at-risk zones were defined by location of Plasmodium falciparum infections in the previous month. Longitudinal ACD and PCD (ACP+PCD) occurred within at-risk zones, where 137 houses (573 persons) were randomly selected as sentinels, each with one month of weekly active sampling. Entomological captures were conducted in the sentinel houses. RESULTS: The PCD incidence was 0.03 P. falciparum and 0.22 Plasmodium vivax infections/person/malaria-season. However, the ACD+PCD prevalence was 0.13 and 0.39, respectively. One explanation for this 4.33 and 1.77-fold increase, respectively, was infection clustering within at-risk zones and contiguous households. Clustering makes PCD, generalized to the entire population, artificially low. Another attributable-factor was that only 41% and 24% of the P. falciparum and P. vivax infections were associated with fever and 80% of the asymptomatic infections had low-density or absent parasitaemias the following week. After accounting for asymptomatic infections, a 2.6-fold increase in ACD+PCD versus PCD was attributable to clustered transmission in at-risk zones. CONCLUSION: Even in low transmission, there are frequent highly-clustered asymptomatic infections, making PCD an inadequate measure of incidence. These findings support a strategy of concentrating ACD and insecticide campaigns in houses adjacent to houses were malaria was detected one month prior.

Adolescent↗

PubMed2006

Vulvovaginal-swab or first-catch urine specimen to detect Chlamydia trachomatis in women in a community setting?

Screening for chlamydia in women is widely recommended. We evaluated the performance of two nucleic acid amplification tests for detecting Chlamydia trachomatis in self-collected vulvovaginal-swab and first-catch urine specimens from women in a community setting and a strategy for optimizing the sensitivity of an amplified enzyme immunoassay on vulvovaginal-swab specimens. We tested 2,745 paired vulvovaginal-swab and urine specimens by PCR (Roche Cobas) or strand displacement amplification (SDA; Becton Dickinson). There were 146 women infected with chlamydia. The assays detected 97.3% (95% confidence interval [CI], 93.1 to 99.2%) of infected patients with vulvovaginal-swab specimens and 91.8% (86.1 to 95.7%) with urine specimens. We tested 2,749 vulvovaginal-swab specimens with both a nucleic acid amplification test and a polymer conjugate-enhanced enzyme immunoassay with negative-gray-zone testing. The relative sensitivities obtained after retesting specimens in the negative gray zone were 74.3% (95% CI, 62.8 to 83.8%) with PCR and 58.3% (95% CI, 46.1 to 69.8%) with SDA. In community settings, both vulvovaginal-swab and first-catch urine specimens from women are suitable substrates for nucleic acid amplification tests, but enzyme immunoassays, even after negative-gray-zone testing, should not be used in screening programs.

Adolescent↗

PubMed1997

Diagnosis of perinatal human immunodeficiency virus infection by polymerase chain reaction and p24 antigen detection after immune complex dissociation in an urban community hospital.

Results of polymerase chain reaction (PCR) and p24 antigen detection after immune complex dissociation (p24-ICD) were compared with antibody results after 18 months of age for human immunodeficiency virus (HIV) diagnosis in 345 prospectively followed, perinatally exposed infants. Of 59 infected and 286 uninfected infants tested at 1-6 months of age, sensitivity and specificity were, respectively, 100% and > 97% for PCR and 90% and > 97% for p24-ICD. Testing was done on > or = 2 occasions in the first 6 months of life in 43 infected infants; 77% had > or = 2 positive results with the same test. Of these infants, 68% had 2 positive p24-ICD tests. In uninfected infants, 96% had only negative tests; none had > 1 positive. By 6 months, all uninfected infants with > or = 2 PCR results could have been diagnosed. HIV status can be determined by PCR by age 6 months in most HIV-exposed infants. p24-ICD should not be used alone, because of its lower sensitivity, but may be useful in areas without advanced laboratory support.

Antigen-Antibody Complex↗

PubMed2003

The effectiveness of community-based visual screening and utility of adjunctive diagnostic aids in the early detection of oral cancer.

A systematic review of community-based oral cancer screening programmes published between 1966 and March 2002 was undertaken. Data relating to study design, sampling and characteristics of the study group, interventions, and reported outcomes and diagnostic value of visual screening or adjunctive diagnostic aids were abstracted from 36 articles meeting inclusion and exclusion criteria. From these reports, there is insufficient evidence to demonstrate the effectiveness of community-based oral cancer visual screening in enhancing the early detection of oral cancer, due to small effect size. While the evidence is fair to support use of toluidine blue as an aid in diagnosis of oral cancer, there is insufficient evidence to determine whether the use of this or other adjunctive techniques will increase the detection of oral malignancies in community screening programmes. Targeted clinical examination of high-risk individuals may be more effective than mass screening in facilitating early detection of oral cancers.

Community Health Services↗

PubMed2005

Multiple and simultaneous detection of specific bacteria in enriched bacterial communities using a DNA microarray chip with randomly generated genomic DNA probes.

A DNA microarray chip for detecting the presence of specific bacterial strains was developed using random genomic probes derived from genomic DNA, i.e., without any sequence information. Thirteen bacteria from different genuses were selected as targets. For the fabrication of the random genomic probes, genomic DNA from pure cultures of each bacterium was fractionated using several pairs of restriction endonucleases. After size fractionation of the genomic DNA fragments, random genomic libraries for each bacterium were constructed. From the library, specific probes were amplified by PCR and the probes were affixed to a slide glass to fabricate the DNA microarray chip. The results from tests with pure and mixed cultures of the bacteria used in the fabrication of the chips showed specific responses and only a small portion of cross-hybridization. This DNA microarray chip was also tested to detect the presence of specific bacteria in mixed populations. In these tests, it was demonstrated that this system provided a fast and specific response to the presence of bacterial species in mixed samples, even in activated sludge samples. This indicates that any DNA microarray chip for the detection of specific bacteria can be fabricated using the same protocols as presented in this study without requiring any genus level sequence information from pure isolates.

Bacterial Typing Techniques↗

PubMed1999

Comparison of serologic tests with urinary antigen detection for diagnosis of legionnaires' disease in patients with community-acquired pneumonia.

OBJECTIVE: To compare serologic methods and detection of urinary antigen in the diagnosis of community-acquired pneumonia. METHODS: Paired sera from 84 patients with community-acquired pneumonia were tested for Legionella pneumophila serogroup (LP SG) 1-7 and Legionella micdadei by use of the indirect immunofluorescence antibody test (IIF), enzyme-linked immunosorbent assay (ELISA) for LP SG 1-7 and complement-fixation (CF) test for LP SG 1. All patients were evaluated by ELISA urinary antigen detection for LP SG 1. RESULTS: Seven patients met the CDC criteria for acute Legionella infection, while in the rest of them we failed to detect urinary Legionella antigen. Thirty-three patients had non-diagnostic IIF antibody titers. Serum ELISA (IgG and/or IgM) was positive in 40 patients. Nine patients showed at least one CF titer of >/=1:32. The sensitivities of ELISA IgM for the first and the second serum samples compared with IIF were 42.8% and 46.6%, respectively, while the specificities were higher, i.e. 87% and 88.4%, respectively. The sensitivities of ELISA IgG for the first and the second samples were 42.8% and 53.3%, and the specificities were 77.9% and 76.8%, respectively. CONCLUSIONS: Although ELISA is simple to perform and easy to automate, we think that its advantages over indirect immunofluorescence and urinary antigen detection remain questionable.

Journal Article↗

PubMed2005

Links between plant and rhizoplane bacterial communities in grassland soils, characterized using molecular techniques.

Molecular analysis of grassland rhizosphere soil has demonstrated complex and diverse bacterial communities, with resultant difficulties in detecting links between plant and bacterial communities. These studies have, however, analyzed "bulk" rhizosphere soil, rather than rhizoplane communities, which interact most closely with plants through utilization of root exudates. The aim of this study was to test the hypothesis that plant species was a major driver for bacterial rhizoplane community composition on individual plant roots. DNA extracted from individual roots was used to determine plant identity, by analysis of the plastid tRNA leucine (trnL) UAA gene intron, and plant-related bacterial communities. Bacterial communities were characterized by analysis of PCR-amplified 16S rRNA genes using two fingerprinting methods: terminal restriction fragment length polymorphisms (T-RFLP) and denaturing gradient gel electrophoresis (DGGE). Links between plant and bacterial rhizoplane communities could not be detected by visual examination of T-RFLP patterns or DGGE banding profiles. Statistical analysis of fingerprint patterns did not reveal a relationship between bacterial community composition and plant species but did demonstrate an influence of plant community composition. The data also indicated that topography and other, uncharacterized, environmental factors are important in driving bacterial community composition in grassland soils. T-RFLP had greater potential resolving power than DGGE, but findings from the two methods were not significantly different.

Bacteria↗

PubMed2000

Rapid detection and quantification of members of the archaeal community by quantitative PCR using fluorogenic probes.

We describe a rapid, reproducible, and sensitive method for detection and quantification of archaea in naturally occurring microbial communities. A domain-specific PCR primer set and a domain-specific fluorogenic probe having strong and weak selectivity, respectively, for archaeal rRNA genes (rDNAs) were designed. A universal PCR primer set and a universal fluorogenic probe for both bacterial and archaeal rDNAs were also designed. Using these primers and probes, we demonstrated that detection and quantification of archaeal rDNAs in controlled microbial rDNA assemblages can be successfully achieved. The system which we designed was also able to detect and quantify archaeal rDNAs in DNA samples obtained not only from environments in which thermophilic archaea are abundant but also from environments in which methanogenic archaea are abundant. Our findings indicate that this method is applicable to culture-independent molecular analysis of microbial communities in various environments.

Archaea↗

PubMed1977

Detection and follow-up of moderate and severe hypertensive subjects in the Australia community.

A national screening project has detected 989 subjects aged 30 to 69 years with untreated moderate or severe hypertension. The 1-2% incidence of this condition indicates a total of about 100,000 people in the Australian community potentially requiring therapy. The sample showed that half the subjects were previously unaware of a blood pressure problem. Those so detected showed a very high rate (90-7%) of acceptance of advice to see their own doctor. The local doctors confirmed the elevated pressure level in nearly two-thirds of the patients referred, and initiated treatment in a similar proportion.

Adult↗

PubMed1997

A self-administered technique for the detection of sexually transmitted diseases in remote communities.

The control of sexually transmitted diseases (STDs) in remote rural communities would be enhanced by a sensitive self-administered method for the detection of asymptomatic infection. Results of conventional methods for the detection of STDs were compared with results of tampon-collected specimens analyzed by polymerase chain reaction (PCR) for 480 women. Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis were detected by routine methods in 4 (1%), 14 (3%), and 41 (9%) samples, respectively, while PCR detected these organisms from 52 (11%), 26 (5%), and 75 (16%) tampons, respectively. The detection of each organism was significantly greater by PCR in tampon-collected samples than by routine conventional methods (P < .01). Discrepant results were confirmed by separate primers in 40 of 48 specimens for N. gonorrhoeae, in 11 of 12 specimens for C. trachomatis, and in 31 of 32 specimens for T. vaginalis. Tampons tested by PCR provide an acceptable and sensitive method for detection of STDs in women living in remote areas.

Animals↗

PubMed2026

Beyond the clinic: a community-embedded, multidomain framework for early detection of glaucoma.

Glaucoma remains one of the leading causes of acquired irreversible blindness worldwide, with normal-tension glaucoma representing the dominant subtype in Japan and several East Asian populations. The insidious, asymptomatic progression of this condition, combined with the demonstrated inadequacy of intraocular pressure alone as a screening criterion, creates a critical gap between disease burden and case detection. Population-based epidemiological studies consistently reveal that the majority of individuals with glaucoma are undiagnosed. Two responses have been suggested: incorporation of retinal imaging into annual health checkups, which warrants formal prospective evaluation, and characterization of individuals at higher risk - integrating genomic risk, oxidative stress biomarkers, systemic lifestyle factors, and ocular blood flow dynamics - which may help identify those in whom damage is most likely to occur. The principal contribution of this Perspective is therefore the implementation model rather than the individual screening components. We introduce the Living Lab ('neighborhood health lab'), a community co-creation platform established under the Japan Science and Technology Agency COI-NEXT 'Vision to Connect' hub at Tohoku University, as a scalable model for operationalizing this framework. Embedded within commercial retail environments, the Living Lab integrates non-invasive screening, longitudinal health data collection, and evidence-based health product development-exemplified by the Ronbun Recipe® concept-within a stakeholder-aligned ecosystem encompassing citizens, researchers, industry, and municipal authorities. Conceived as a platform for well-being rather than as a disease-specific screening service, it engages individuals who are asymptomatic, undiagnosed, and outside existing screening pathways, and who would not otherwise be assessed at all.

Humans↗

PubMedDate not supplied

Evaluation of a nested-PCR assay for Streptococcus pneumoniae detection in pediatric patients with community-acquired pneumonia.

The aim of the present work was to evaluate the usefulness of a simplified method for DNA extraction coupled to a nested-PCR protocol, based on the amplification of pneumolysin gene fragments for the diagnosis of pneumococcal pneumonia in pediatric patients with clinical and radiological evidence of bacterial infection. Bacterial DNA was extracted from sera by boiling and used without further purification in the PCR for the pneumolysin gene. None toxic reagents were used and the necessary steps to obtain the DNA were left at a minimum; furthermore, it overcomes the use of expensive commercial kits for DNA purification. The total procedure can be completed the same day of sampling and, most important, it avoids the use of sophisticated technology. Both in vitro analytical specificity and sensitivity (10 CFU/ml) of the assay were similar to those previously reported. When clinical samples were tested, the rate of positivity was shown to be 83.3% and 71% in pediatric patients with positive (group a) and negative blood cultures (group b), respectively. In group a, DNA detection was successful in samples from children without treatment or with less than 48 h of antibiotic therapy. None amplification was obtained from sera patients with viral infection or in samples from healthy controls. The application of the strategy described in this paper substantially seems to improve the diagnostic process in a determinate group: blood culture-negative children with pneumonia.

Bacteremia↗

PubMed2002

A heteroduplex method for detection of targeted sub-populations of bacterial communities.

We describe a simple method, based on heteroduplex mobility analysis of 16S rDNA fragments, for targeted detection of sub-populations of bacteria within diverse microbial communities. A small (ca. 200 bp) polymorphic fragment of the bacterial 16S rRNA gene was amplified from sample DNA using universal primers. Sample products were hybridised with a fluorescently labelled fragment amplified from a selected 'reporter' organism representing the target group. The resulting products were resolved and the labelled heteroduplex pairs detected on non-denaturing gels using automated DNA detection technology. A model, based on analysis of samples with known 16S rDNA sequences, demonstrates that heteroduplex mobility is inversely correlated with genetic distance and that beyond 26% genetic difference, heteroduplex products are not detected. The utility of the method was tested by field studies in which stream biofilms could be characterised by heteroduplex profiles generated with heterotrophic and autotrophic reporter organisms representing target groups.

Bacteria↗

PubMed2003

[Usefulness of a new fast technique for detection of pneumococcal antigen in the diagnosis of community pneumonia].

With the objective of analyzing the usefulness of a new technique of fast detection of pneumococcal antigen in urine (Binax NOW Streptococcus pneumoniae urinary antigen test) 163 community pneumonia episodes were reviewed. The test was positive in 30 cases, and gave rise to therapeutic implications in 12 patients. The global sensitivity was 57%, being superior in patients with HIV infection (70%), and the specificity was 91.6%. In 16 episodes it was the only diagnostic test of pneumococcal infection. The determination of pneumococcal antigen through this technique is a useful tool for the diagnosis of community pneumonia, mainly due its high specificity.

Antigens, Bacterial↗

PubMed2006

Detection of Anaplasma platys and Babesia canis vogeli and their impact on platelet numbers in free-roaming dogs associated with remote Aboriginal communities in Australia.

OBJECTIVE: To detect Anaplasma platys and Babesia canis vogeli infection, using polymerase chain reaction (PCR)-based assays, in free-roaming dogs associated with eight Aboriginal communities in remote areas of Australia and to determine the impact of infection through the assessment of platelet numbers. PROCEDURES: Blood samples from 215 dogs were screened by PCR for A platys and B canis vogeli using established genus-specific DNA primers for the 16S and 18S rRNA genes respectively. Both A platys DNA and B canis vogeli DNA were confirmed from the screening PCR either by sequencing or by the use of species-specific primers. Peripheral blood films from 92 of the 215 dogs were used to estimate platelet numbers through an indirect method. RESULTS: Of 215 dogs, 69 (32%) were positive for A platys, 22 (10%) for B canis vogeli and 24 (11%) for both. The two organisms were detected singularly and as coinfection in all communities. For the 92 dogs in which peripheral blood films were examined, the mean estimated platelet counts for the non-infected dogs was 318 x 10(9)/L, those infected with A platys alone was 256 x 10(9)/L, those with B canis vogeli alone was 276 x 10(9)/L and those infected with both parasites was 169 x 10(9)/L. In young dogs, infection produced significantly decreased mean platelet counts when compared to uninfected dogs. Thrombocytopenia (< 200 x 10(9)/L) was detected in 18 (51%) dogs infected with A platys alone, 3 (33%) dogs infected with B canis vogeli alone, 13 (72%) dogs coinfected, and 8 (27%) uninfected dogs. CONCLUSIONS: A platys and B canis vogeli infection, either singularly or together, was widespread in free roaming dogs associated with remote Aboriginal communities in the Northern Territory and north-western New South Wales. Moreover, both A platys and B canis vogeli infections were associated with a reduction in mean platelet numbers in dog populations, particularly in young dogs. The fact that 51% of dogs infected with A platys alone and 72% dogs coinfected were thrombocytopenic compared to 27% of uninfected dogs suggests that the organism alone or in combination with B canis vogeli has the potential to cause thrombocytopenia and perhaps contribute to a clinical bleeding disorder in infected dogs.

Anaplasma↗

PubMed1996

The ICS-'BPH' Study: the psychometric validity and reliability of the ICSmale questionnaire.

OBJECTIVE: To assess the validity and reliability of the ICSmale questionnaire developed for the International Continence Society-'Benign Prostatic Hyperplasia' (ICS-'BPH') study. PATIENTS AND METHODS: Urology departments in 12 countries recruited 1271 consecutive men > 45 years old, with lower urinary tract symptoms and possible benign prostatic obstruction, to the ICS-'BPH' study (the clinical group); 423 ambulent men were recruited from a general practice in the UK to provide a community group. Each individual was asked to complete the wide-ranging ICSmale questionnaire, comprising questions concerned with urinary symptoms, the bother they cause, and issues of quality of life and sexual function. Content, construct and criterion validity of the symptom and problem questions were assessed by interviews with patients and urologists, testing hypotheses within sub-studies, and in relation to frequency-volume diaries and uroflowmetry. Reliability was assessed by measures of internal consistency and a test-retest analysis. RESULTS: The ICSmale questionnaire was easy to complete. It was clearly able to differentiate between men in clinical and community populations, and detected the expected positive age gradient for most symptoms in the community group. There was reasonable agreement between relevant parts of the questionnaire and frequency-volume charts when a relatively flexible approach was taken, but there was a very poor relationship between questions assessing strength of stream and the results of uroflowmetry. Internal consistency was high, and overall the questionnaire demonstrated good test-retest reliability. CONCLUSION: The self-completed ICSmale questionnaire had high levels of psychometric validity and reliability.

Aged↗

PubMed1992

The differentiation of Chlamydia species by antigen detection in sputum specimens from patients with community-acquired acute respiratory infections.

An amplified enzyme immunoassay (IDEIA III: Dako Diagnostics Ltd) for detecting genus-specific chlamydia antigen was evaluated prospectively on 286 respiratory specimens from 275 patients presenting with community-acquired pneumonia or persistent chest infection. Nineteen patients had evidence of recent chlamydial infection, having two or more positive sputum or serological markers. Sputa from two other patients were ELISA-positive in the absence of other positive criteria and were regarded as false-positive results. When compared with a direct immunofluorescence test for chlamydial elementary bodies (EBs) using a genus-specific monoclonal antibody, the ELISA gave a positive predictive value of 91% and a negative predictive value of 99%. Non-specific problems with a wide variety of other micro-organisms isolated from the sputa were not encountered. Attempts to differentiate between Chlamydia psittaci, Chlamydia pneumoniae and Chlamydia trachomatis using genus-specific lipopolysaccharide reactive--and species-specific major outer membrane protein--monoclonal antibodies were encouraging and results were substantiated, in most patients, by the species-specific serological assays of the whole-cell-inclusion immunofluorescence or micro-immunofluorescence assays. The study demonstrated that antigen detection techniques offer scope for routine laboratories to diagnose chlamydial respiratory infections rapidly and reliably and may enable differentiation to species level. Although immunofluorescence offers marginally greater sensitivity and specificity when compared with ELISA, the latter is less subjective and less demanding. Sixty-eight per cent of these infections would have remained undiagnosed despite the general availability of ELISA tests.

Adult↗