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At least 307 records · Page 17Linked to original sources
PubMed2005

Usefulness of the direct agglutination test in the early detection of subclinical Leishmania donovani infection: a community-based study.

The value of a direct agglutination test (DAT) in the detection of subclinical infections with Leishmania donovani has recently been investigated in the Indian state of Bihar, after the sensitivity and specificity of the test had been determined. When used to screen sera from 108 parasitologically confirmed cases of visceral leishmaniasis, 50 patients with active, non-leishmanial infection, and 641 healthy controls living close to, or distant from, an endemic area, the test was found to be 91.7% sensitive and 100% specific if a titre of 1:800 was used as the threshold for seropositivity. During a longitudinal clinical study in a rural, VL-endemic area of the Indian state of Bihar, the test was used, with 1:800 set as the threshold titre, to determine the baseline prevalence of infection with L. donovani among villagers who, though showing no symptoms of VL, had recently been febrile for at least 2 weeks. The 234 subjects of this study were either VL-case contacts [i.e. members of households in which there were active or cured VL cases (N=78)] or the members of control households with no cases or history of the disease (N=156). The results of DAT at the start of the study indicated that 49 (20.9%) of the subjects--29 (37.2%) of the VL-case contacts and 20 (12.8%) of the other subjects--were seropositive and therefore probably had subclinical infections with L. donovani. During the subsequent 9 months of follow-up, however, only eight of the subjects found seropositive at the start of the study--seven (24.1%) of the seropositive case contacts but only one (5.0%) of the other seropositives--developed symptomatic VL, all by month 6 of the follow-up. Compared with their neighbours, therefore, individuals who shared households with active or cured cases of VL appeared at greater risk not only of L. donovani infection (indicating focal transmission) but also of developing symptomatic disease once infected. Curiously, among the seropositive case contacts, those from the households that harboured active cases of VL at the baseline survey were less likely to develop symptomatic VL during the 9 months of follow-up than those from households that harboured only cured cases (18.8% v. 30.8%). The wide-spread use of DAT could allow the detection and early treatment of latent L. donovani infections and so contribute to the elimination of VL, at least as a public-health problem, from India.

Agglutination Tests↗
PubMed2001

Analysis of bacterial community structure in sulfurous-oil-containing soils and detection of species carrying dibenzothiophene desulfurization (dsz) genes.

The selective effects of sulfur-containing hydrocarbons, with respect to changes in bacterial community structure and selection of desulfurizing organisms and genes, were studied in soil. Samples taken from a polluted field soil (A) along a concentration gradient of sulfurous oil and from soil microcosms treated with dibenzothiophene (DBT)-containing petroleum (FSL soil) were analyzed. Analyses included plate counts of total bacteria and of DBT utilizers, molecular community profiling via soil DNA-based PCR-denaturing gradient gel electrophoresis (PCR-DGGE), and detection of genes that encode enzymes involved in the desulfurization of hydrocarbons, i.e., dszA, dszB, and dszC. Data obtained from the A soil showed no discriminating effects of oil levels on the culturable bacterial numbers on either medium used. Generally, counts of DBT degraders were 10- to 100-fold lower than the total culturable counts. However, PCR-DGGE showed that the numbers of bands detected in the molecular community profiles decreased with increasing oil content of the soil. Analysis of the sequences of three prominent bands of the profiles generated with the highly polluted soil samples suggested that the underlying organisms were related to Actinomyces sp., Arthrobacter sp., and a bacterium of uncertain affiliation. dszA, dszB, and dszC genes were present in all A soil samples, whereas a range of unpolluted soils gave negative results in this analysis. Results from the study of FSL soil revealed minor effects of the petroleum-DBT treatment on culturable bacterial numbers and clear effects on the DBT-utilizing communities. The molecular community profiles were largely stable over time in the untreated soil, whereas they showed a progressive change over time following treatment with DBT-containing petroleum. Direct PCR assessment revealed the presence of dszB-related signals in the untreated FSL soil and the apparent selection of dszA- and dszC-related sequences by the petroleum-DBT treatment. PCR-DGGE applied to sequential enrichment cultures in DBT-containing sulfur-free basal salts medium prepared from the A and treated FSL soils revealed the selection of up to 10 distinct bands. Sequencing a subset of these bands provided evidence for the presence of organisms related to Pseudomonas putida, a Pseudomonas sp., Stenotrophomonas maltophilia, and Rhodococcus erythropolis. Several of 52 colonies obtained from the A and FSL soils on agar plates with DBT as the sole sulfur source produced bands that matched the migration of bands selected in the enrichment cultures. Evidence for the presence of dszB in 12 strains was obtained, whereas dszA and dszC genes were found in only 7 and 6 strains, respectively. Most of the strains carrying dszA or dszC were classified as R. erythropolis related, and all revealed the capacity to desulfurize DBT. A comparison of 37 dszA sequences, obtained via PCR from the A and FSL soils, from enrichments of these soils, and from isolates, revealed the great similarity of all sequences to the canonical (R. erythropolis strain IGTS8) dszA sequence and a large degree of internal conservation. The 37 sequences recovered were grouped in three clusters. One group, consisting of 30 sequences, was minimally 98% related to the IGTS8 sequence, a second group of 2 sequences was slightly different, and a third group of 5 sequences was 95% similar. The first two groups contained sequences obtained from both soil types and enrichment cultures (including isolates), but the last consisted of sequences obtained directly from the polluted A soil.

Bacteria↗
PubMed2004

A 3-year prospective study of a urinary antigen-detection test for Streptococcus pneumoniae in community-acquired pneumonia: utility and clinical impact on the reported etiology.

To evaluate the efficacy of a rapid immunochromatographic membrane test (ICT) for the detection of Streptococcus pneumoniae urinary antigen for diagnosing S. pneumoniae pneumonia, ICT was performed with urine samples using the Binax NOW Streptococcus pneumoniae kit at the time of admission. The results were compared with those from conventional microbiological studies. Three hundred and forty-nine adult patients with CAP who were admitted to the hospital were studied prospectively between February 2001 and January 2004. The ICT test was positive in 115 (33.0%) of 349 patients enrolled into the study and in 63 (75.9%) of 83 patients with pneumococcal pneumonia confirmed by conventional methods. The test revealed a sensitivity of 75.9% and a specificity of 94.0% with conventional microbiological criteria used as the reference standard. The positive predictive value was 91.3%, and the negative predictive value was 82.6%. The clinical features of 53 patients in whom ICT was positive and no pathogen was identified showed no significant difference from those of 83 patients who had pneumococcal pneumonia identified by conventional methods. The diagnostic yield of pneumococcal pneumonia was increased up to 38.9% using ICT combined with conventional methods. The Binax NOW ICT to detect S. pneumoniae urinary antigen is therefore a rapid and useful method for diagnosing pneumococcal pneumonia. Induction of ICT will prove the predominance of S. pneumoniae in the etiology of CAP.

Adolescent↗
PubMed2001

Screening mammography with computer-aided detection: prospective study of 12,860 patients in a community breast center.

PURPOSE: To prospectively assess the effect of computer-aided detection (CAD) on the interpretation of screening mammograms in a community breast center. MATERIALS AND METHODS: Over a 12-month period, 12,860 screening mammograms were interpreted with the assistance of a CAD system. Each mammogram was initially interpreted without the assistance of CAD, followed immediately by a reevaluation of areas marked by the CAD system. Data were recorded to measure the effect of CAD on the recall rate, positive predictive value for biopsy, cancer detection rate, and stage of malignancies at detection. RESULTS: When comparing the radiologist's performance without CAD with that when CAD was used, the authors observed the following: (a) an increase in recall rate from 6.5% to 7.7%, (b) no change in the positive predictive value for biopsy at 38%, (c) a 19.5% increase in the number of cancers detected, and (d) an increase in the proportion of early-stage (0 and I) malignancies detected from 73% to 78%. CONCLUSION: The use of CAD in the interpretation of screening mammograms can increase the detection of early-stage malignancies without undue effect on the recall rate or positive predictive value for biopsy.

Adult↗
PubMed2006

Simultaneous detection of pathogens in clinical samples from patients with community-acquired pneumonia by real-time PCR with pathogen-specific molecular beacon probes.

In this study, real-time PCR with pathogen-specific molecular beacons (MB) and primers was evaluated for prediction of community-acquired pneumonia (CAP) causative agents, detecting six main CAP agents, Streptococcus pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophila, and Streptococcus pyogenes, simultaneously. The PCR assay was evaluated for fresh clinical specimens from infants and children (n = 389) and from adults (n = 40). The MB probes and primers are both pathogen specific, namely, the lytA gene for S. pneumoniae, the mip gene for L. pneumophila, and 16S rRNA genes for the remaining four organisms. DNA extraction of clinical specimens was performed with a commercially available EXTRAGEN II kit, and amplification was performed with Stratagene Mx3000P. The limit of detection for these pathogens ranged from 2 copies to 18 copies. The whole process from DNA extraction to the analysis was finished in less than 2 h. The obtained sensitivity and specificity of this real-time PCR study relative to those of conventional cultures were as follows: 96.2% and 93.2% for S. pneumoniae, 95.8% and 95.4% for H. influenzae, 100% and 100% for S. pyogenes, and 100% and 95.4% for M. pneumoniae, respectively. The sensitivity and specificity for M. pneumoniae relative to those of a serologic assay were 90.2% and 97.9%, respectively. In six clinical samples of C. pneumoniae, the real-time PCR gave positive predictable values, and in those cases, elevation of the titer value was also observed. In conclusion, we demonstrated that a real-time PCR assay with pathogen-specific MB is useful in identifying CAP causative agents rapidly and in examining the clinical course of empirical chemotherapy in a timely manner, supporting conventional culture methods.

Child, Preschool↗
PubMed2006

A review of methods to detect cases of severely malnourished children in the community for their admission into community-based therapeutic care programs.

BACKGROUND: The complexity and cost of measuring weight-for-height make it unsuitable for use by community-based volunteers. This has led community therapeutic care programs to adopt a two-stage screening and admission procedure in which mid-upper-arm circumference (MUAC) is used for referral and weight-for-height is used for admission. Such a procedure results in many individuals being referred for care on the basis of MUAC but subsequently being refused treatment because they do not meet the weight-for-height admission criterion. This "problem of rejected referrals" has proved to be a major barrier to program uptake. OBJECTIVE: To systematically review methods to detect cases of severely malnourished children in the community for their admission into community-based therapeutic care programs. METHODS: Clinical and anthropometric methods for case detection of severely malnourished children in the community were reviewed with regard to their ability to reflect both mortality risk and nutritional status. RESULTS: MUAC, with the addition of the presence of bipedal edema, was found to be the indicator best suited to screening and case detection of malnutrition in the community. The case definition "MUAC < 110 mm OR the presence of bipedal edema," with MUAC measured by a color-banded strap, is suitable for screening and case detection of malnutrition in the community for children aged between 6 and 59 months. Monitoring and discharge criteria were also reviewed. CONCLUSIONS: There is no compelling evidence to support a move away from using weight in combination with clinical criteria for monitoring and discharge.

Anthropometry↗
PubMed2003

The Ashkelon Hypertension Detection and Control Program (AHDC Program): a community approach to reducing cardiovascular mortality.

BACKGROUND: Blood pressure (BP) reduction is crucial in reducing cardiovascular (CV) morbidity and mortality in the community. Subjects aged 20-65 seldom visit the primary care clinics, so they are unlikely to be detected without an active outreach screening program. The aim of the project was to prepare a professional doctor-nurse screening team, who will instruct those found to be at high risk in control of their risk factors, in order to reduce CV morbidity and mortality. METHODS: During a 10-year period (1980-1990), teams examined 12,202 subjects, (mean age 51 +/- 7 years, range 20-65 years) accounting for 23.4% of the total regional population. High risk subjects underwent an intensive CV risk factor control program. RESULTS: Subjects (3,506 or 28.6%) were found to have one or more CV risk factors (hypertension, obesity, smoking, hypercholesterolemia). During an average of 2 years, follow-up BP, weight reduction, and smoking cessation remained statistically significant. Total cholesterol was unchanged. Over this period, the standardized mortality ratio (SMR) in the area for acute MI fell from 100 to 76 (P < 0.01), for CV disease from 129 to 107 (P < 0.0001), and for hypertension from 121 to 87 (P < 0.1 NS). The project saved many life-years at no additional net cost to society, and cost effectiveness analysis showed positive results. CONCLUSIONS: A community approach with mainly nonpharmacological treatment is feasible and cost effective in reducing CV morbidity and mortality.

Adolescent↗
PubMed2000

A comparison of selected diversity, similarity, and biotic indices for detecting changes in benthic-invertebrate community structure and stream quality.

Implementation of advanced wastewater treatment at the two municipal wastewater-treatment plants for Indianapolis, Indiana, resulted in substantial improvement in the quality of the receiving stream and significant changes in the benthic-invertebrate community. Diversity, similarity, and biotic indices were compared to determine which indices best reflected changes in the composition of the biota in the river. None of the indices perfectly reflected the changes in river quality or community structure. Similarity indices, especially percentage similarity, exhibit the most promise of the three classes of indices. Diversity indices were least useful, wrongly indicating that water quality deteriorated after the upgrade of the wastewater-treatment plants. The most descriptive tool in analyzing the data was the percentage of Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa present. Using a mixture of indices and other analytical tools, such as EPT, in the analysis of biological data will ensure the most effective investigations of water quality.

Animals↗
PubMed2005

Use of a whole-cell biosensor and flow cytometry to detect AHL production by an indigenous soil community during decomposition of litter.

Quorum sensing, mediated by acylated homoserine lactones (AHLs), is well described for pure culture bacteria, but few studies report detection of AHL compounds in natural bacterial habitats. In this study, we detect AHL production during a degradation process in soil by use of whole-cell biosensor technology and flow cytometry analysis. An indigenous soil bacterium, belonging to the family of Enterobacteriaceae, was isolated and transformed with a low-copy plasmid harboring a gene encoding an unstable variant of the green fluorescent protein (gfpASV) fused to the AHL-regulated P(luxI) promoter originating from Vibrio fischeri. This resulted in a whole-cell biosensor, responding to the presence of AHL compounds. The biosensor was introduced to compost soil microcosms amended with nettle leaves. After 3 days of incubation, cells were extracted and analyzed by flow cytometry. All microcosms contained induced biosensors. From these microcosms, AHL producers were isolated and further identified as species previously shown to produce AHLs. The results demonstrate that AHL compounds are produced during degradation of litter in soil, indicating the presence of AHL-mediated quorum sensing in this environment.

4-Butyrolactone↗
PubMed2005

Performance characteristics of clinical diagnosis, a clinical decision rule, and a rapid influenza test in the detection of influenza infection in a community sample of adults.

STUDY OBJECTIVE: The accurate diagnosis of influenza remains a diagnostic dilemma. We examine the performance of various strategies for diagnosing influenza infection in an unselected sample of adults during influenza season. METHODS: Consecutive adults presenting to a university emergency department or urgent care clinic between January and March 2002 with acute respiratory complaints were eligible for this prospective observational study. The performance of clinician judgment, a rapid influenza test, and a clinical prediction rule in predicting influenza infection was evaluated using referent standard of reverse transcriptase polymerase chain reaction. Statistical significance was assessed using McNemar's test of proportions. RESULTS: Fifty-three of 258 (21%) patients had a positive influenza reverse transcriptase polymerase chain reaction test. Overall, clinician judgment showed sensitivity of 29% (95% confidence interval [CI] 18% to 43%) and specificity of 92% (95% CI 87% to 95%). The rapid influenza test showed a sensitivity of 33% (95% CI 22% to 47%) and specificity of 98% (95% CI 96% to 99%). The clinical prediction rule showed a sensitivity of 40% (95% CI 27% to 54%) and specificity of 92% (95% CI 87% to 95%). Clinician judgment when patients presented within 48 hours showed a sensitivity of 67% (95% CI 39% to 86%) and specificity of 96% (95% CI 81% to 99%). Neither the rapid influenza test (P=.10) nor the clinical prediction rule (P=.42) was superior to clinician judgment alone in the diagnosis of influenza. CONCLUSION: The suggestion that a clinical decision rule or a rapid influenza test is better than clinical judgment alone for the diagnosis of influenza in an unselected patient population is not supported by this study.

Adolescent↗
PubMed1997

The performance of simple instruments in detecting geriatric conditions and selecting community-dwelling older people for geriatric assessment.

BACKGROUND: comprehensive geriatric assessment (CGA) appears to be less effective when performed in outpatient clinics than in hospital settings. The effectiveness of outpatient CGA might be improved by selectively targeting frailer community-dwelling elderly people. The purpose of this study was to evaluate the clinical performance of rapidly-administered standard screening measures for geriatric syndromes in selecting community-dwelling older people for outpatient CGA. METHODS: urban-dwelling older people were screened for CGA at community sites using a self-administered questionnaire containing standardized measures for each of four geriatric target conditions: depression, urinary incontinence, falls and functional impairment. The study sample included all 150 consecutive subjects who were screened, failed on one or more of the four target criteria and completed community-based, academically administered CGA. Diagnostic accuracy of the screening instruments was assessed using CGA diagnoses as the 'gold standard'. In addition, patients' potential for benefiting from CGA was determined by whether they received major medical recommendations for further evaluation or treatment. RESULTS: after completing CGA, 60.2% of those failing on functional impairment, 53.5% of those failing on depression, 30.7% of those failing on falls and 92.7% of those on urinary incontinence, were confirmed as having these or highly related conditions as clinical problems. Overall, 81.3% of the subjects completing CGA received the least one major recommendations for further medical intervention; most of these recommendations (79.5%) were for a target-related condition and the further remainder (20.5%) addressed another significant medical condition. CONCLUSION: simple screening instruments used in community settings have variable degrees of accuracy, but may be markers for frailty and thus can identify older people likely to benefit from geriatric assessment.

Activities of Daily Living↗
PubMed1978

Co-circulation of two influenza A (H3N2) antigenic variants detected by virus surveillance in individual communities.

From March through June 1977 a total of 31 influenza A (H3N2) viruses were isolated from students with respiratory disease who were seen at the student health service on the Berkeley campus of the University of California, and 32 influenza A (H3N2) viruses were isolated from persons who participated in a city-wide febrile respiratory disease surveillance program in Seattle. The antigenic specificity of the hemagglutinin was determined for each isolate by hemagglutination inhibition testing with sera from ferrets infected with prototype strains A/Victoria/3/75 and A/Texas/1/77. In each of the three months, April, May and June, A/Victoria/3/75-like and A/Texas/1/77-like viruses were identified among isolates from both communities, and the numbers of isolates of the two antigenic variants from patients seen with influenza-like illnesses were similar. The findings emphasize the need to examine multiple isolates even from within single communities to determine the antigenic specificity of current strains of influenza virus.

Adolescent↗