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PubMed2004

Method to find community structures based on information centrality.

Community structures are an important feature of many social, biological, and technological networks. Here we study a variation on the method for detecting such communities proposed by Girvan and Newman and based on the idea of using centrality measures to define the community boundaries [M. Girvan and M. E. J. Newman, Proc. Natl. Acad. Sci. U.S.A. 99, 7821 (2002)]. We develop an algorithm of hierarchical clustering that consists in finding and removing iteratively the edge with the highest information centrality. We test the algorithm on computer generated and real-world networks whose community structure is already known or has been studied by means of other methods. We show that our algorithm, although it runs to completion in a time O(n4) , is very effective especially when the communities are very mixed and hardly detectable by the other methods.

Algorithms↗
PubMed2006

Diversity of a stable enrichment culture which is useful for silage inoculant and its succession in alfalfa silage.

Alfalfa is a kind of forage that is difficult to ensile for good quality. Therefore, inoculants are always used to enhance the preservation of alfalfa silage. Through continuous restricted subcultivation, a lactic acid bacteria community (Al2) was selected from well-fermented alfalfa silage, which sharply decreased the pH level and produced a large amount of lactic acid. The adding of Al2 to alfalfa at ensiling resulted in a more rapid drop in pH and higher levels of lactic acid, and it also reduced the ammonia-nitrogen content significantly (P < 0.01). Plate isolation, denaturing gradient gel electrophoresis (DGGE) and the construction of a 16S rRNA gene clone library were used to identify the composition diversity of the Al2 community; seven strains were detected in the community, the predominant strain belonging to Lactobacillus plantarum. Samples of alfalfa silages of duration 0, 2, 5, 10, 20 and 30 days were studied with DGGE analysis. The DGGE band patterns of Al2-treated and non inoculated were rather different, and the components of Al2 were the dominant bacteria in Al2-treated silages, especially L. plantarum, while Pediococcus pentosaceaus was predominant in naturally fermented alfalfa silage.

Comet Assay↗
PubMed2006

The microbial degradation of azimsulfuron and its effect on the soil bacterial community.

AIMS: Azimsulfuron is a recently introduced sulfonylurea herbicide useful in controlling weeds in paddy fields. To date very little information is available on the biodegradation of this pesticide and on its effect on the soil microbial community. The aim of this work was to study its biodegradation both in slurry soil microcosms and in batch tests with mixed and pure cultures. METHODS AND RESULTS: Azimsulfuron was applied to forest bulk soil in order to study its effect on the structure of the bacterial soil community, as detectable by denaturant gradient gel electrophoresis (DGGE) analyses. Biodegradation and abiotic processes were investigated by HPLC analyses. In addition, a microbial consortium was selected, that was able to use azimsulfuron as the sole energy and carbon source. One of the metabolites produced by the consortium was isolated and identified through LC-MS analyses. Cultivable bacteria of the consortium were isolated and identified by 16S rDNA sequencing (1400 bp). CONCLUSIONS: Azimsulfuron treatment seems to have the ability to cause changes in the bacterial community structure that are detectable by DGGE analyses. It is easily biodegraded both in microcosms and in batch tests, with the formation of an intermediate that was identified as 2-methyl-4-(2-methyl-2H-tetrazol-5-yl)-2H-pyrazole-3-sulfonamide. SIGNIFICANCE AND IMPACT OF THE STUDY: The study increases the knowledge on the biodegradation of azimsulfuron and its effects on the soil microbiota.

Bacteria↗
PubMed1990

Costing a community based screening programme for the detection of glaucoma.

The cost of detecting a case of glaucoma in a community based screening programme was calculated using data from a pilot study on a population aged 50 and over. The cost per screen was estimated at 3.35 pounds with a total cost of 311 pounds per case detected. These estimates include the cost of both the algorithmically based screening programme and the hospital assessment of true and false positives. These costs are considered to compare favourably with the potential costs incurred by paying optometrists to screen high risk groups whilst providing the opportunity to detect over twice the number of cases of occult glaucoma.

Community Health Services↗
PubMedDate not supplied

Serum cholesterol and coronary heart disease risk in female and older hypertensives. The experience under usual community care in the Hypertension Detection and Follow-up Program.

The coronary heart disease (CHD) risk function associated with baseline serum cholesterol levels among women and older hypertensives was determined for the 5455 participants who were randomized in the Hypertension Detection and Follow-up Program (HDFP), referred to usual care in 14 US communities, and followed for the years 1974 through 1979. The risk of fatal CHD in relation to serum cholesterol for those under age 65 appeared as strong in women as in men in age- and race-adjusted analyses stratified by serum cholesterol levels; however, there was no association of serum cholesterol levels with combined fatal plus nonfatal incident coronary events for these women, adjusting for other major risk factors and covariables. There was no association of serum cholesterol with fatal or combined fatal plus nonfatal CHD events in either adjusted or unadjusted analyses for older hypertensive women. In contrast to the findings for women, serum cholesterol levels were strongly predictive of fatal plus nonfatal CHD in both younger and older hypertensive men, controlling for the effects of other factors such as age, antecedent history of antihypertensive medication, and presence of comorbidity. This study, based on the experience of the usual care group within the HDFP, was observational in nature. Clinical trials of specific regimens of serum cholesterol lowering in hypertensives are required definitively to determine their efficacy and safety for these high-risk patients; however, the experience within the HDFP indicates the desirability of detection and prudent management of hypercholesterolemia in older as well as younger male hypertensives.

Age Factors↗
PubMed2004

Correlates of firesetting in a community sample of young adolescents.

OBJECTIVE: To investigate relationships between firesetting, antisocial behaviour, individual, family and parenting factors in a large community sample of adolescents. METHOD: A cross-sectional study of students (n = 2596) aged 13 years on average, from 27 schools in South Australia with a questionnaire on firesetting, antisocial behaviour (adapted 21-item Self Report Delinquency Scale), risk-taking, drug use, suicidality, physical and sexual abuse, depressive symptomatology, hopelessness, anxiety, locus of control, self-esteem, family functioning (McMaster Family Assessment Device) and parenting style (Influential Relationships Questionnaire). Data analysis included chi2, anova and logistic regression. RESULTS: Large significant differences are found between firesetters and non-firesetters on all measures. Among adolescents with serious levels of antisocial behaviour (7+ acts included in diagnostic guidelines for DSM-IV conduct disorder), firesetters differ from non-firesetters in reporting more extreme antisocial behaviour (10+ acts), extreme drug use, suicidal behaviour, and perceived failure at school. Gender differences are apparent. A study limitation is the single item assessment of firesetting. CONCLUSIONS: Self-report firesetting is strongly associated with extreme antisocial behaviour in young community adolescents, in support of existing evidence from incarcerated delinquent and psychiatric populations. Early detection of community firesetters demands further assessment and intervention. Clinicians should consider its coexistence with serious drug use and high risk-taking (especially in girls), and suicidality, sexual and physical abuse (in boys).

Adolescent↗
PubMed2006

Early detection of the first episode of schizophrenia and suicidal behavior.

OBJECTIVE: The suicide rate in schizophrenia is high, with the risk being highest early in the course. The rate of suicide attempts before treatment onset is also high and is often the event leading up to first treatment contact. A previous report showed that the duration of untreated psychosis can be reduced through an early detection program, and that the reduction was associated with lower symptom levels at treatment initiation. Treatment programs that bring first-episode patients into treatment at lower symptom levels can have the potential to reduce risk for suicide attempts. METHOD: The authors examined consecutive patients with nonorganic, nonaffective psychosis who sought initial treatment at psychiatric treatment units in four catchment areas: two that had an early detection program and two that did not. RESULTS: The rate of severe suicidality (plans or attempts) was significantly higher in subjects from communities without the early detection program relative to those from early detection communities, even after adjustments for known predictors of suicidality. CONCLUSION: Early detection programs that bring patients into treatment at lower symptom levels may reduce suicidality risk at first treatment contact.

Adult↗
PubMed2003

The CUSCORE test and the q-interval in cluster analyses of colon cancer and of lymphoma among asbestos workers.

Exposure to a carcinogen is likely to be reflected by temporal clustering of cancer cases among the community members. Detection of such clustering is a complicated task in general and more so in a small workplace community with low turnover rate. In this study we applied the CUSCORE test and the q-interval statistic to lymphoma and colon cancer death data among 2200 asbestos workers. The CUSCORE test was applied in order to identify clusters, and the q-interval was used to provide clues related to the cause of the cluster. We also evaluated and tested the data according to the standardized mortality ratio (SMR). Significant increases in both colon cancer and lymphoma among asbestos workers in Israel (1987-1997) were demonstrated by the CUSCORE test but not so by the SMR. The fact that an apparent clustering was observed from the pattern of the q-intervals leads to the conclusion that the detected clusters are real.

Asbestos↗
PubMed1994

Value of prostate cancer screening in a comprehensive community cancer center.

Early detection of prostate cancer may help decrease cancer deaths from this disease despite the increased incidence of prostate cancer. In 1990 and 1991 we conducted one-day "screens" for prostate cancer. This analysis was undertaken to determine the value of the screening procedures for detecting prostate cancer in the community. A total of 579 men, aged 39-84 years (mean 58 years), were evaluated by digital rectal examination (DRE) by a urologist, serum prostate specific antigen (PSA) determination by monoclonal antibody assay, and completion of a detailed questionnaire. Forty-eight percent had not seen a physician in over 2 years; 17% had a 1st- or 2nd-degree relative with prostate cancer. There was a 25% "suspicious" rate including 76 (13%) men with abnormal DRE only, 48 (8%) with abnormal PSA only, and 21 (4%) with abnormal DRE and PSA. Patients with findings suspicious for cancer were recontacted by telephone at 2-month intervals for 6 months to determine outcome because subsequent diagnostic management was at the discretion of practicing physicians. By 6 months, 84% of patients with abnormal findings had seen a physician as recommended. Of the 76 with abnormal DRE only, 11 were biopsied and only one cancer was found (9%). Of 48 with an elevated PSA only, 19 were biopsied; 11 (58%) had cancer (9/9 positive transrectal ultrasound) and 8 had no cancer at biopsy (5/5 negative transrectal ultrasound). Of 21 with both tests suspicious, 11 were biopsied and 9 had cancer (82%). Thus, by 6 months after each screen there was a 3.5% overall cancer detection rate for the whole population screened, a 67% positive biopsy rate among those with an elevated PSA, a 45% positive biopsy detection rate among those with an abnormal DRE, and a 51% positive biopsy rate among all those biopsied. Eighty percent of the PSA elevations were between 4.1 and 10.0 ng/ml. This screening experience yielded several new diagnoses of prostate cancer, and the use of serum PSA levels and ultrasound-guided biopsy was associated with a high positive biopsy rate for cancer.

Adult↗
PubMed2003

Comparison of conventional viral cultures with direct fluorescent antibody stains for diagnosis of community-acquired respiratory virus infections in hospitalized children.

OBJECTIVE: Because of the widespread availability of rapid viral antigen testing, many institutions never adopted a routine practice of ordering viral cultures to detect community-acquired respiratory viruses (CRVs). The ease of performing complete viral studies in our on site laboratory allowed us to assess the clinical implications of the absence of conventional culture results in previously healthy hospitalized children with CRV infections. METHODS: From June 1997 through May 2000, the results of direct immunofluorescence assay (DFA) of 1069 nasopharyngeal swab (NP) specimens were compared with simultaneously inoculated conventional tube cell cultures for detection of CRVs. In addition the medical records of 140 previously healthy infants and children hospitalized for management of lower respiratory tract infections caused by culture-proved CRVs were reviewed. RESULTS: Viruses were isolated or detected by DFA or viral culture or both in 468 (30%) of the 1557 NP samples evaluated. The most common CRV isolated was respiratory syncytial virus (49%), followed by parainfluenza viruses (15%), influenza A viruses (14%), rhinoviruses (8%), adenoviruses (4%), enteroviruses (4%) and influenza B viruses (1%). Of the 1069 NP specimens for which both viral culture and rapid antigen testing were performed, 190 specimens were DFA-positive and culture-positive, 7 specimens were DFA-positive and culture-negative, 35 specimens were DFA-negative and culture-positive and 837 specimens were DFA-negative and culture-negative. The overall sensitivity, specificity, positive predictive value and negative predictive value of DFA were 84, 99, 96 and 96%, respectively. Of the 140 hospitalized patients with culture-proved viral cultures (89 respiratory syncytial virus, 22 influenza A, 20 parainfluenza virus and 9 adenovirus), the mean duration of hospital stay was 3.6 days, and the mean time for viral cultures to become positive was 7.7 days (P < 0.001, signed rank test). One hundred twenty (86%) viral cultures did not become positive until after the patient had been discharged from the hospital. In no case was the clinical decision regarding the patient's treatment or discharge from the hospital based on the results of viral culture. CONCLUSIONS: We conclude that positive viral cultures have no impact on clinical decision making and management of healthy children during hospitalization for illness attributable to community-acquired respiratory viruses.

Child↗
PubMed2001

Species coexistence in temperate, mixed deciduous forests.

The response of tree life-history traits to community profiles (horizontal and vertical heterogeneity, disturbances and biotic interactions) determines community assembly rules, which are currently a hot issue in community ecology. Important mechanisms of coexistence differ throughout the developing stages of tree life history. Many processes of niche partitioning and tradeoffs that potentially enable tree coexistence have been reported to be present in temperate forests, although some of these life-history traits are either correlated with each other or are not independent. Not all of the proposed mechanisms explain coexistence equally well; some could predominate in determining the community organization of forest communities. Population studies need to concentrate more on the component species of a target community to detect the ecological assembly rule. These approaches can also address how chance factors contribute to the composition of temperate tree communities, which might be less dependent on chance than are tropical ones.

Journal Article↗
PubMed1994

The detection of mental disorders in the community using a 20-item interview version of the General Health Questionnaire.

A 20-item interview version of the General Health Questionnaire (GHQ) was used to presumptively identify cases with mental disorders in a sample of 810 community residents. Subjects also were examined by psychiatrists using the Present State Examination (PSE). The screening instrument performed well in detecting PSE-CATEGO syndromes related to anxiety and depression, but less well in detecting psychotic syndromes and cognitive impairment. The overall sensitivity of the instrument for any PSE-CATEGO syndrome was 48%. The study elucidates the specific nature of the psychopathology that this version of the GHQ is likely to detect in the community.

Adolescent↗
PubMed1996

Serum prostate-specific antigen and digital rectal examination for early detection of prostate cancer in a national community-based program. The Prostate Cancer Education Council.

OBJECTIVES: This study analyzed methods of prostate cancer early detection in community settings throughout the United States against standards and findings of earlier studies conducted at academic medical centers. METHODS: The study was conducted at 148 clinical centers during Prostate Cancer Awareness Week in September 1993 and continued through June 1994. A total of 31,953 eligible subjects were tested by both digital rectal examination (DRE) and prostate-specific antigen (PSA). PSA was tested with the Abbott IMx PSA assay and reported by Roche Biomedical, Inc. RESULTS: The study confirmed that elevated PSA levels (greater than 4.0 ng/mL) aid in the detection of organ-confined prostate cancer when used in conjunction with the DRE. Reflecting more conservative biopsy decision-making practices, study results nonetheless are comparable to earlier reports. Among 1307 subjects who underwent biopsy, 322 cancers were detected. The cancer detection rate was 3.6% for PSA, 3.0% for DRE, and 4.7% if either test result was positive. The positive predictive value (PPV) for elevated PSA levels (greater than 4.0 ng/mL) was 3l.6%, significantly better (P < 0.0001) than the PPV for abnormal DRE results (25.5%). Nearly 90% (88.9%) of staged cancers were diagnosed as localized. Elevated PSA levels detected more localized cancers (76 of 105 [72.4%]) than the DRE (72 of 105 [68.6%]). Of localized tumors, 33 (31.4%) were missed by DRE and detected solely by PSA, and 29 (27.6%) were missed by PSA and detected solely by DRE. The combined use of the two methods detected 33 additional localized tumors. CONCLUSIONS: Community practice throughout the United States demonstrates that PSA and DRE are consistently effective and efficient in the early detection of prostate cancer.

Aged↗
PubMed1996

Barium enema: detection of colonic lesions in a community population.

OBJECTIVE: The purposes of this study were to assess the prevalence of colonic lesions detected at barium enema in a community practice, to compare the findings at barium enema between patients who are asymptomatic and have no known risk factors for colorectal cancer (screening group) and patients who have symptoms of colonic disease or have known risk factors, and to determine if a questionnaire about symptoms and risk factors is an appropriate screening tool. SUBJECTS AND METHODS: A self-administered questionnaire about colorectal symptoms and risk factors was given to 1779 patients scheduled for barium enema examination. On the basis of their responses, patients were divided into three groups: screening group (asymptomatic, without risk factors), symptomatic, and asymptomatic with risk factors. Each patient underwent a fluoroscopic barium enema. We then compared the results (number, histologic type, size of lesion(s), location in the colon, and Patient's age) and risk factors among the three groups. RESULTS: At least one lesion within the colorectum was found in 166 (9%) of 1779 patients at combined proctosigmoidoscopy and barium enema. The prevalence of lesions in the 111 patients with at least one lesion above the rectum at barium enema was 4% (32 of 738) for the screening group, 8% (38 of 476) for asymptomatic patients with risk factors, and 7% (41 of 565) for symptomatic patients (p = .015 when comparing the prevalence in the screening group with the prevalences in the other two groups). Twenty-nine percent of all colonic lesions were found in the screening group. Among the asymptomatic patients, risk factors that included a history of colorectal polyps and advanced age were associated with a significantly higher prevalence of colonic polyps found at barium enema. In the symptomatic group, if patients with histories of polyps were excluded, we were unable to identify other risk factors that led to a significantly higher prevalence of polyps. CONCLUSION: Asymptomatic patients without known risk factors have a significantly lower prevalence of colonic polyps than either symptomatic patients or patients with risk factors alone. Despite this lower prevalence, 29% of all lesions in our series were in the screening group. Assessment of risk factors through a patient questionnaire was not helpful in identifying a group of patients with a higher prevalence of lesions--except for a history of polyps. Management decisions based on a patient questionnaire should be approached with caution. When low-risk patients are denied screening examinations, a significant number of lesions will be missed.

Aged↗
PubMed1999

Factors influencing the detection rate of drug-related problems in community pharmacy.

This study analyzes relationships between the number of drug-related problems detected in community pharmacy practice and the educational level and other characteristics of pharmacy personnel and their work sites. Random samples of pharmacists, prescriptionists and pharmacy technicians were drawn nationwide in Sweden. One hundred and forty-four (63%) of those meeting the inclusion criteria agreed to take part. The participants documented medication-related problems, interventions and patient variables on a data collection form. The drug-related problems were weighted by the number of patients served by each professional. The regression analysis showed the educational level of the professional to have a statistically significant effect on the detection rate, with pharmacists finding on average 2.5 more drug-related problems per 100 patients than prescriptionists and about 3.6 more than technicians. Previous participation in a study or activity on drug-related problems and the size of the pharmacy also had statistically significant effects on the problem detection rate. The use of open-ended questions to create a dialogue with the patient seemed to be a successful means to discover problems. The results of this study indicate the importance of education and training of pharmacy personnel in detection of drug-related problems. This findings speaks in favor of increasing the pharmacist to other personnel ratio, provided the higher costs will be offset by societal benefits.

Drug-Related Side Effects and Adverse Reactions↗
PubMed1993

Laboratory methods for the detection of hemoglobinopathies in the community hospital.

In the 1990s, community hospital laboratories can expect to evaluate anemia in patients from increasingly diverse racial and ethnic backgrounds, which will require the implementation of increasingly sophisticated laboratory methods for the detection of hemoglobinopathies. This article reviews the standard methods of alkaline and acid hemoglobin identification, and the methods of hemoglobin quantitation and ancillary tests are presented. Finally, a protocol is proposed that will allow the community hospital laboratory physicians to diagnose the majority of clinically significant hemoglobinopathies efficiently and accurately.

Clinical Laboratory Techniques↗
PubMed2006

Evaluating the use of a Streptococcus pneumoniae urinary antigen detection kit for the management of community-acquired pneumonia in Japan.

BACKGROUND: The urinary antigen detection kit for Streptococcus pneumoniae was tested. OBJECTIVES: It was our aim to evaluate the usefulness of the immunochromatographic membrane test by doing a large prospective study of community-acquired pneumonia (CAP) in Japan. METHODS: We prospectively evaluated the use of the S. pneumoniae urinary antigen detection kit and analyzed the treatment and clinical effect seen in patients with positive test kit results. One hundred and fifty-six patients with CAP admitted to our hospital between October 2001 and September 2003 were evaluated. RESULTS: In 49% of these CAP patients, the causative microorganisms were isolated. S. pneumoniae was suspected to be the causative microorganism in 15%, but positive results of the urinary antigen detection kit indicated S. pneumoniae to be a probable microorganism in 28%, even though antibiotics had previously been administered to half of the patients. The kit was particularly useful for diagnosing patients with poor quality sputum in whom antibiotics treatment nevertheless had to be selected. Antibiotics appropriate for S. pneumoniae (mainly penicillin) were given. The treatment was found to have excellent clinical results in 89% of the CAP patients. CONCLUSIONS: The S. pneumoniae urinary antigen detection kit was considered to be useful in selecting treatment since there was a high level of clinical effectiveness when the most suitable antibiotics were immediately administered to positive patients. The use of the S. pneumoniae urinary antigen kit is rapid and simple compared with conventional microbiological procedures.

Adolescent↗