SEARCH · Search PubMed

Results for “Community Detection”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 955 records · Page 53Linked to original sources

PubMed2003

The isotope array, a new tool that employs substrate-mediated labeling of rRNA for determination of microbial community structure and function.

A new microarray method, the isotope array approach, for identifying microorganisms which consume a (14)C-labeled substrate within complex microbial communities was developed. Experiments were performed with a small microarray consisting of oligonucleotide probes targeting the 16S rRNA of ammonia-oxidizing bacteria (AOB). Total RNA was extracted from a pure culture of Nitrosomonas eutropha grown in the presence of [(14)C]bicarbonate. After fluorescence labeling of the RNA and microarray hybridization, scanning of all probe spots for fluorescence and radioactivity revealed that specific signals were obtained and that the incorporation of (14)C into rRNA could be detected unambiguously. Subsequently, we were able to demonstrate the suitability of the isotope array approach for monitoring community composition and CO(2) fixation activity of AOB in two nitrifying activated-sludge samples which were incubated with [(14)C]bicarbonate for up to 26 h. AOB community structure in the activated-sludge samples, as predicted by the microarray hybridization pattern, was confirmed by quantitative fluorescence in situ hybridization (FISH) and comparative amoA sequence analyses. CO(2) fixation activities of the AOB populations within the complex activated-sludge communities were detectable on the microarray by (14)C incorporation and were confirmed independently by combining FISH and microautoradiography. AOB rRNA from activated sludge incubated with radioactive bicarbonate in the presence of allylthiourea as an inhibitor of AOB activity showed no incorporation of (14)C and thus was not detectable on the radioactivity scans of the microarray. These results suggest that the isotope array can be used in a PCR-independent manner to exploit the high parallelism and discriminatory power of microarrays for the direct identification of microorganisms which consume a specific substrate in the environment.

Ammonia↗

PubMed1976

Precipitating antibody response to malarial S-antigens.

The gel diffusion test has been used to detect antibodies to malarial S-antigens. Sera were obtained from entire Gambian village communities, from young children with acute P. falciparum malaria, from children convalescent from such infections and from immune adults. In community studies, small selections of S-antigens detected antibody frequently in sera from older persons but rarely in sera from young children. Larger panels of antigens detected antibodies in sera from half of 50 malarious children while homologous antibody responses were observed in 22% of 267 children followed at intervals during convalescence from malaria. In these latter cases, antibody tended to appear more swiftly when antigen was lost rapidly from the circulation, and observations made on individual responses indicated that antibody production was influenced by factors other than the intrinsic properties of the antigens. In adult sera antibodies usually occurred in association with IgG.

Adolescent↗

PubMed2001

Failure to detect HLA-A*6802-restricted CD8+ T cells specific for Chlamydia trachomatis antigens in subjects from trachoma-endemic communities.

The role of HLA-A*6802-restricted CD8+ T cells in chlamydial disease was investigated in human ocular infections. Peptides with predicted binding motifs for HLA-A*6802 were synthesized using sequences based on chlamydial antigens, major outer membrane protein (MOMP), macrophage infectivity potentiator (MIP) and heat shock protein (hsp70). Peptides were pooled according to Chlamydia trachomatis protein type and serovar, and were tested in 51Cr-release cytotoxic T lymphocyte (CTL) and enzyme-linked immunospot (ELISPOT) assays, using peripheral blood mononuclear cells (PBMC) isolated from subjects living in trachoma-endemic communities in The Gambia. Significant CTL activity or interferon-gamma release was not detected in any of the subjects, suggesting either that HLA-A*6802 CD8+ T cells may not be important in ocular infections or that the peptides chosen did not represent epitopes.

Adolescent↗

PubMed1999

The impact of a community-based heart disease prevention program in a low-income, inner-city neighborhood.

OBJECTIVES: This study evaluated the impact of a 4-year, community-based cardiovascular disease prevention program among adults aged 18 to 65 years living in St-Henri, a low-income, innercity neighborhood in Montreal, Quebec. METHODS: Awareness of and participation in the program were monitored in 3 independent sample telephone surveys. Self-reported behaviors were compared in St-Henri and a nearby comparison community before and after program implementation in both a 3-year repeat independent sample survey and a 5-year longitudinal cohort telephone survey. RESULTS: Awareness of the program reached 37.4%, but participation was low (2%-3%). There were no secular declines in smoking or high-fat diet; physical inactivity increased in both communities. There were no statistically significant program effects detected in the independent sample surveys, although physical inactivity increased more in the comparison community than in St-Henri. In the longitudinal cohort sample, there was a small, statistically significant increase favoring St-Henri in frequency of cholesterol checkups. CONCLUSIONS: Despite careful adaptation of the program to the local social context, there were few community-wide program effects. However, several component interventions showed promise in terms of community penetration and impact.

Adult↗

PubMedDate not supplied

[Notes on some self-induced diseases in prison communities].

The self-induced and simulated diseases in prison communities are numerous and not always easy to detect. This is, at any rate, a peculiar phenomenon that also involves other closed communities external to the prison environment, such as those of the large built-up areas, of the factories, of the schools, of the barracks, etc... As a rule, recourse is had, in the latter, to self-induction and simulation to achieve economic or absenteeistic purposes. In prison communities, self-induction and simulation are instead implemented in order to escape the rigours of the law and detention itself. It is an unquestionable fact, however, that nowadays this phenomenon is regressing, chiefly thanks to the coming into force of law No. 354 of July 26, 1975 on the penitentiary System, that is certainly determining radical improvements within the prisons.

Conjunctivitis↗

PubMed2006

Recurrent seasonal variations in abundance and composition of filamentous SOL cluster bacteria (Saprospiraceae, Bacteroidetes) in oligomesotrophic Lake Mondsee (Austria).

The spatial and temporal variation of SOL cluster bacteria was assessed in oligomesotrophic Lake Mondsee and adjacent lakes by fluorescence in situ hybridization over two annual cycles. The filamentous SOL bacteria were present in Lake Mondsee throughout the study period, and the seasonal dynamics of the SOL community were remarkably similar with respect to both abundance and composition in the two consecutive years. Only two of the three SOL subclusters were detected in Lake Mondsee and four connected lakes. These two populations significantly differed in size distribution and demonstrated pronounced but recurrent differences in seasonality and length of period of appearance in Lake Mondsee. Extensive sampling of the lakes in September 2003 revealed low horizontal variation in the composition of the SOL community within Lake Mondsee but marked variations with depth. Between connected habitats pronounced differences in the composition and abundance of the SOL community were detected. The interaction of SOL bacteria with bacterivorous protists, mesozooplankton, and phytoplankton was investigated in order to reveal variables controlling the structure and dynamics of SOL communities. No strong indication for a bottom-up influence of phytoplankton was found, while the estimated community grazing rates of mesozooplankton on SOL bacteria indicated a top-down control of SOL abundance during mesozooplankton peaks in spring and early autumn. Furthermore, species-specific differences in grazing of mesozooplankton on SOL bacteria were observed. In general, the overall composition of SOL communities was controlled by abiotic factors (water chemistry), while their dynamics seemed to be controlled by abiotic and biotic interactions.

Animals↗

PubMed2003

Genetic characterization of the nitrate reducing community based on narG nucleotide sequence analysis.

The ability of facultative anerobes to respire nitrate has been ascribed mainly to the activity of a membrane-bound nitrate reductase encoded by the narGHJI operon. Respiratory nitrate reduction is the first step of the denitrification pathway, which is considered as an important soil process since it contributes to the global cycling of nitrogen. In this study, we employed direct PCR, cloning, and sequencing of narG gene fragments to determine the diversity of nitrate-reducing bacteria occurring in soil and in the maize rhizosphere. Libraries containing 727 clones in total were screened by restriction fragment analysis. Phylogenetic analysis of 128 narG sequences separated the clone families into two main groups that represent the Gram-positive and Gram-negative nitrate-reducing bacteria. Novel narG lineages that branch distinctly from all currently known membrane bound nitrate-reductase encoding genes were detected within the Gram-negative branch. All together, our results revealed a more complex nitrate-reducing community than did previous culture-based studies. A significant and consistent shift in the relative abundance of the nitrate-reducing groups within this functional community was detected in the maize rhizosphere. Thus a substantially higher abundance of the dominant clone family and a lower diversity index were observed in the rhizosphere compared to the unplanted soil, suggesting that a bacterial group has been specifically selected within the nitrate-reducing community. Furthermore, restriction fragment length polymorphism analysis of cloned narG gene fragments proved to be a powerful tool in evaluating the structure and the diversity of the nitrate-reducing community and community shifts therein.

Bacteria, Anaerobic↗

PubMed1995

Implementing assertive community treatment teams.

The Connecticut Department of Mental Health began creating assertive community treatment teams in 1987. The authors describe the approach taken by the department in defining the assertive community treatment model, in creating new assertive community treatment teams, and in monitoring the creation and functioning of these teams to ensure that fidelity to the assertive community treatment model is maintained. Assertive community treatment teams can be created even in the absence of funding for new staff by reconfiguring current community-based staff and by moving staff from state hospitals to the community. Preliminary data from a randomized trial in Connecticut comparing assertive community treatment with high-quality case management in areas with an array of community services indicated that the intended models were replicated, with variations in practice style across programs. Clients in assertive community treatment were in the hospital about half as often as clients in standard services and were also less likely to be without a permanent residence. Training and ongoing monitoring of assertive community treatment teams are necessary to detect practices that diverge from the intervention model so that corrective action can be taken.

Adult↗

PubMed2007

Population structure and resistance genes in antibiotic-resistant bacteria from a remote community with minimal antibiotic exposure.

In a previous study, we detected unexpectedly high levels of acquired antibiotic resistance in commensal Escherichia coli isolates from a remote Guaraní Indian (Bolivia) community with very low levels of antibiotic exposure and limited exchanges with the exterior. Here we analyzed the structure of the resistant E. coli population from that community and the resistance mechanisms. The E. coli population (113 isolates from 72 inhabitants) showed a high degree of genetic heterogeneity, as evidenced by phylogenetic grouping (77% group A, 10% group B1, 8% group D, 5% group B2) and genotyping by randomly amplified polymorphic DNA (RAPD) analysis (44 different RAPD types). The acquired resistance genes were always of the same types as those found in antibiotic-exposed settings [blaTEM, blaPSE-1, catI, cmlA6, tet(A), tet(B), dfrA1, dfrA7, dfrA8, dfrA17, sul1, sul2, aphA1, aadA1, aadA2, aadA5, aadB, and sat-1]. Class 1 and class 2 integrons were found in 12% and 4% of the isolates, respectively, and harbored arrays of gene cassettes similar to those already described. The cotransferability of multiple-resistance traits was observed from selected isolates and was found to be associated with resistance conjugative plasmids of the F, P, and N types. Overall, these data suggest that the resistance observed in this remote community is likely the consequence of the dissemination of resistant bacteria and resistance genes from antibiotic-exposed settings (rather than of an independent in situ selection) which involved both the clonal expansion of resistant strains and the horizontal transfer/recombination of mobile genetic elements harboring resistance genes.

Anti-Bacterial Agents↗

PubMed1991

Drug use in pregnancy: obstetric perspectives.

The incidence of perinatal chemical use is undoubtedly much higher than the rate of use detected at any single point during pregnancy. As the prevalence is likely to be 10% or greater in any community, obstetricians need to employ measures to detect chemical use, similar to measures taken to detect birth defects, gestational diabetes, syphilis, gonorrhea, and preeclampsia. The use of screening protocols must be accompanied by an awareness of the need for intervention and treatment resources. Identification of perinatal chemical use should be for purposes of medical and social intervention, not criminal prosecution. Obstetric management should focus on the prevention of preterm delivery and intrauterine growth retardation. It should be recognized that pregnancy provides a unique opportunity for the encouragement of positive health behaviors. Programs that include such components may be able to achieve more lasting effects.

Female↗

PubMed1990

[Post-education in clinical problems of narcotics abuse].

Since 1985 the Hjellestad Clinic, in cooperation with the Norwegian Directorate for the Prevention of Alcohol and Drug Problems, has offered five 40 hour courses a year for primary health care workers in order to provide them with the necessary knowledge dealing with drug- and alcohol-related issues in the local community. The focus is on early detection and simple intervention strategies. Since 1989 on we have offered two additional courses on special topics such as family, drug and alcohol problems, management of drug- and alcohol-related crises in the local community etc. The article discusses a new speciality in the "treatment of addictive behaviours".

Alcoholism↗

PubMed2004

Metamorphosis of a scleractinian coral in response to microbial biofilms.

Microorganisms have been reported to induce settlement and metamorphosis in a wide range of marine invertebrate species. However, the primary cue reported for metamorphosis of coral larvae is calcareous coralline algae (CCA). Herein we report the community structure of developing coral reef biofilms and the potential role they play in triggering the metamorphosis of a scleractinian coral. Two-week-old biofilms induced metamorphosis in less than 10% of larvae, whereas metamorphosis increased significantly on older biofilms, with a maximum of 41% occurring on 8-week-old microbial films. There was a significant influence of depth in 4- and 8-week biofilms, with greater levels of metamorphosis occurring in response to shallow-water communities. Importantly, larvae were found to settle and metamorphose in response to microbial biofilms lacking CCA from both shallow and deep treatments, indicating that microorganisms not associated with CCA may play a significant role in coral metamorphosis. A polyphasic approach consisting of scanning electron microscopy, fluorescence in situ hybridization (FISH), and denaturing gradient gel electrophoresis (DGGE) revealed that coral reef biofilms were comprised of complex bacterial and microalgal communities which were distinct at each depth and time. Principal-component analysis of FISH data showed that the Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, and Cytophaga-Flavobacterium of Bacteroidetes had the largest influence on overall community composition. A low abundance of Archaea was detected in almost all biofilms, providing the first report of Archaea associated with coral reef biofilms. No differences in the relative densities of each subdivision of Proteobacteria were observed between slides that induced larval metamorphosis and those that did not. Comparative cluster analysis of bacterial DGGE patterns also revealed that there were clear age and depth distinctions in biofilm community structure; however, no difference was detected in banding profiles between biofilms which induced larval metamorphosis and those where no metamorphosis occurred. This investigation demonstrates that complex microbial communities can induce coral metamorphosis in the absence of CCA.

Animals↗

PubMed2004

Community based participatory approaches to address health disparities in Hawai'i: recent applications in cancer prevention, detection and treatment programs.

Assessment of recent trends in the prevalence and incidence of cancer, and its associated risk and protective factors in the State of Hawai'i illustrate that there are definite ethnic, socio-economic, and geographic health disparities. Disparities in access to health care are reflected in decreased and under utilization of all types of preventive cancer screening tests and decreased proportions of people with health insurance coverage. Increases in obesity mirror U.S. national trends and disproportionately affect certain ethnic groups and those with low income. Tobacco use has increased among at-risk populations including: certain ethnic groups, those with low-income and/or low education and those in rural areas. Data that reveal continuing or worsening health disparities imply that either the old methods have not been effective and/or resources are not available or are not being applied to address such disparities. Promising methodologies and programmatic focuses to reduce health disparities are needed as mechanisms for improving the circumstances of at-risk populations. Community based participatory approaches are described here for cancer prevention, detection, and treatment programs that utilize culturally appropriate methods.

Community Health Planning↗

PubMed1990

A community-wide program in breast self-examination training and maintenance.

This study reports on the effects of innovative community-wide breast self-examination education approaches in increasing breast self-examination frequency and quality, and ability to detect breast lumps during a 1-year training program and a second-year maintenance program. Four Vermont communities were randomly assigned to receive breast self-examination training plus maintenance, training alone, control (with full measurement), and low-measurement control. Random digit dialing telephone surveys were conducted at baseline and at 1- and 2-year follow-up with a panel of 637 women representing all adult women in the first three communities. The low-measurement control community received only baseline and second-year follow-up surveys with a panel of 238 women. Home interviews to determine breast self-examination palpation skills and lump detection on silicone breast models were conducted in first- and second-year follow-up surveys. Results of the first-year follow-up survey indicated significant increases in breast self-examination frequency, quality, and number of lumps detected for women in communities receiving the training program compared with controls; in the second year, women in the community also receiving breast self-examination maintenance showed greater improvement in reported breast self-examination quality and detected more breast lumps than did women in other communities.

Adult↗

PubMed2002

Local surveillance of influenza in the United Kingdom: from sentinel general practices to sentinel cities?

Surveillance of influenza in England and Wales utilises a disparate geographical network of general practices to provide clinical data in the form of weekly consultation rates for influenza and 'influenza-like illness'. This network accurately detects and monitors seasonal influenza activity at national and supra-regional levels. Localised regional and sub-regional epidemics are less easily detected. We describe a localised epidemic of influenza affecting a deprived urban community in the North West of England that was detected by a close knit network of general practices participating in the surveillance of communicable diseases as part of a primary care health needs assessment initiative.

Adolescent↗

PubMedDate not supplied

Depressive symptoms in elderly patients predict poor adjustment after somatic events.

OBJECTIVE: The authors tested the hypothesis that elderly subjects with premorbid depressive symptoms are at increased risk of poor adjustment after a somatic event. METHODS: The GLAS study contains a baseline assessment and a follow-up of subjects who experienced post-baseline acute myocardial infarction, cancer, congestive heart failure, or fall-related injury of the extremities within 5 years after baseline assessment. Follow-up was conducted at 8 weeks, 6 months, and 1 year after the somatic event. Of a baseline sample of 5,279 elderly subjects (57 and older), 1,124 subjects who experienced one of the specified events were contacted, and sufficient follow-up data were obtained from 558 subjects. Authors analyzed the course of self-reported physical, role, and social functioning, and general health and well-being in subjects without baseline limitations. Patients with poor adjustment after the event were compared with patients with good adjustment on baseline depressive symptoms. They used logistic-regression analysis, controlling for several confounders. RESULTS: In multivariate analyses, pre-event depressive symptoms were associated with an increased risk of poor adjustment in terms of social and role functioning, well-being, and general health, but not physical functioning. CONCLUSIONS: Elderly persons living in the community reporting depressive symptoms are at increased risk of poor psychosocial adjustment after a somatic event. Each reported baseline depressive symptom was associated with an increased risk of chronic decline; this finding stresses the importance of detecting and treating depression in community-living elderly persons.

Adjustment Disorders↗

PubMed2004

[Analysis on the characteristics of blood serum Ab-IgG detective result of severe acute respiratory syndrome patients in Guangzhou, China].

OBJECTIVE: To probe blood serum Ab-IgG characteristics of severe acute respiratory syndrome (SARS) patients in Guangzhou and investigate the related factors. METHODS: The serum of such population diagnosed as SARS convalescent patients, non-SARS patients, family consanguineous contraction persons, wild animal and vegetable salesman and community common people was collected. The lab detective method of ELISA was adopted for these serum samples. And the epidemic investigations for the SARS patients were also carried out. RESULTS: Of these populations, the detective rate of Ab-IgG for the clinic diagnosed SARS patients, which was 53.7%; That for the wild animal salesman and community common people were 16.7% and 0.9%, respectively. Among the clinic diagnosed SARS patients, the positive antibody detective rate was 90.4% for those which had specific contact history or infectivity, which was higher than that for other population. Among the specific contact history or infectivity cases, the antibody positive rate for the young and the old was lower than that for the adult. Meanwhile the difference did not exist among other cases. The antibody positive rate was identical between the male and the female. And the antibody detective rate was decreased by the month. CONCLUSION: As a whole SARS-CoV Ab-IgG detective rate for the clinic diagnosed SARS patients was 53.7% only. The reasons for that mainly lie in the wrong clinic diagnosis besides these factors such as age, hormone use and reagent and so on. The combination of lab detection results and epidemic investigation was propitious to the diagnosis veracity. It was impossible for the sub-clinic infection of SARS-CoV virus. The importance in the virus transmitting course need to be further studied.

Adult↗

PubMedDate not supplied

[Arsenic levels in drinking water supplies from underground sources in the community of Madrid].

BACKGROUND: In 1998, arsenic concentrations of more than 50 micrograms/l were detected in some drinking water supplies from underground sources in the Autonomous Community of Madrid, which is the maximum permissible concentration for drinking water in Spain. These two facts have meant the getting under way of a specific plan for monitoring arsenic in the drinking water in the Autonomous Community of Madrid. METHODS: The results of the first two sampling processes conducted in the arsenic level monitoring plan set out are presented. In the initial phase, water samples from 353 water supplies comprised within the census of the Public Health Administration of the Autonomous Community of Madrid were analyzed. A water supply risk classification was made based on these initial results. In a second phase, six months later, the analyses were repeated on those 35 water supplies which were considered to possibly pose a risk to public health. RESULTS: Seventy-four percent (74%) of the water supplies studied in the initial phase were revealed to have an arsenic concentration of less than 10 micrograms/l, 22.6% containing levels of 10 micrograms/l-50 micrograms/l, and 3.7% over 50 micrograms/l. Most of the water supplies showing arsenic levels of more than 10 micrograms/l are located in the same geographical area. In the second sampling process (six months later), the 35 water supplies classified as posing a risk were included. Twenty-six (26) of these supplies were revealed to have the same arsenic level ((10-50 micrograms/l), and nine changed category, six of which had less than 10 micrograms/l and three more than 50 micrograms/l. CONCLUSIONS: In the Autonomous Community of Madrid, less than 2% of the population drinks water coming from supplies which are from underground sources. The regular water quality monitoring conducted by the Public Health Administration has led to detecting the presence of more than 50 micrograms/l of arsenic in sixteen drinking water supplies from underground sources, which is the maximum permissible level under the laws currently in force in Spain. Measures have been taken to prevent water from being used from these water supplies. Around 20% of the water supplies studies must take measures in the near future to lower the arsenic concentration to below 10 micrograms/l when the water directive which is currently in the process of being written into Spanish law enters into effect.

Arsenic↗