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At least 649 records · Page 36Linked to original sources
PubMed2002

[Detection of acute infection due to legionella pneumophila in patient with community acquired pneumonia in Buenos Aires city].

Community-acquired pneumonia (CAP) is caused by different microorganisms, their frequency varying in each community. Legionella pneumophila has been reported as etiologic agent of CAP. The aim of our study was to determine the incidence of acute infection due to Legionella pneumophila in a group of adult patients in Buenos Aires city. Adults of both sexes with CAP diagnosis were included and two serum samples, acute and convalescence (2-4 weeks apart from each other), were tested to detect antibodies against Legionella pneumophila by indirect immunofluorescence (IFI) (Organon Teknica, NC, USA). Ninety-two of the enrolled patients were evaluable, average age 56 years, 55% men (males), 52.2% did not require hospitalization. Three patients (3.3%) fulfilled the serologic diagnostic criteria for Legionella pneumophila acute infection. None of them were confirmed by microorganism isolation. The actual incidence of CAP caused by Legionella pneumophila in Argentina has not yet been established. It will require studies including larger numbers of patients and the use of simple and sensitive tests, such as Legionella pneumophila urinary antigen detection, to establish the exact role of this pathogen in our community.

Adolescent↗
PubMed2001

Ozone air quality over north america: part II--an analysis of trend detection and attribution techniques.

Assessment of regulatory programs aimed at improving ambient O3 air quality is of considerable interest to the scientific community and to policymakers. Trend detection, the identification of statistically significant long-term changes, and attribution, linking change to specific climatological and anthropogenic forcings, are instrumental to this assessment. Detection and attribution are difficult because changes in pollutant concentrations of interest to policymakers may be much smaller than natural variations due to weather and climate. In addition, there are considerable differences in reported trends seemingly based on similar statistical methods and databases. Differences arise from the variety of techniques used to reduce nontrend variation in time series, including mitigating the effects of meteorology and the variety of metrics used to track changes. In this paper, we review the trend assessment techniques being used in the air pollution field and discuss their strengths and limitations in discerning and attributing changes in O3 to emission control policies.

Air Pollutants↗
PubMed2005

In situ analysis of native microbial communities in complex samples with high particulate loads.

In the present study a procedure combining a cell extraction method and Fluorescence In Situ Hybridization (FISH) for molecular monitoring and quantification of bacteria in soil and aquifer samples is presented. FISH was applied to bacterial cells extracted from the matrix by density gradient centrifugation. This separation method was applied to soil and aquifer samples and produced high cell recovery of 76.5%+/-4.4 and 78.0%+/-3.2, respectively. FISH, performed on the harvested cells, permitted a perfect visualization and quantification of bacteria. This approach is therefore promising for in situ detection of indigenous bacterial communities in complex samples.

Bacteria↗
PubMed2006

Abomasal nematode community in an alpine chamois (Rupicapra r. rupicapra) population before and after a die-off.

Abomasa of 185 chamois shot during 5 consecutive hunting seasons were collected as part of a health monitoring program in an alpine area of Italy and examined for nematodes. The data were obtained during both the preceding period and that following a severe die-off caused by a pneumonia outbreak. Prevalence, mean abundance, mean intensity, and Thul Importance index were consistently high, in particular for Haemonchus contortus, having a low host specificity and high pathogenic potential. Species typical of cervids were also consistently detected. The abomasal nematode community showed an isolationist structure, suggesting its composition was primarily determined by external factors such as interspecific interaction among host species and environmental conditions. The effect of different factors (host sex, sampling site, and time) on nematode counts and aggregation were analyzed and discussed considering the peculiarities of the study site and the chamois population crash. In the light of parallel results for health monitoring, abomasal parasitism could represent a predisposing factor for the observed die-off.

Abomasum↗
PubMedDate not supplied

Longitudinal screening for prostate cancer with prostate-specific antigen.

OBJECTIVE: To determine for the first 4 years of serial prostate-specific antigen (PSA)-based screening trends in compliance, prevalence of abnormal screening test results, cancer detection rates, and stage and grade of cancers detected. DESIGN: A community-based study of serial screening for prostate cancer with serum PSA measurements. SETTING: University medical center. SUBJECTS: A total of 10 248 male volunteers at least 50 years old who were screened at 6-month intervals for a minimum of 48 months. MAIN OUTCOME MEASURES: The proportion of men who returned for serial screening, the proportion with elevated PSA levels, the proportion with newly elevated PSA levels, prostate cancer detection rates, and the distribution of tumor stages and grades at diagnosis. RESULTS: At 48 months, 79% of volunteers returned for screening. During this interval there was a decrease in the proportion of volunteers with serum PSA levels higher than 4.0 ng/mL (from 10% to 6%-7%), in cancer detection rates (from 3% to <1%), and in the proportion with clinically advanced cancer (from 6% to 2%). In men who underwent surgery, the proportion with high-grade cancer decreased (from 11% to 6%), and the proportion with pathologically advanced cancer was proportionately reduced but not significantly reduced (from 33% to 27%). CONCLUSIONS: With serial PSA-based screening, the proportion of men with abnormal test results decreased, and the prostate cancer detection rate decreased to near the reported population-based incidence rate. There was also a shift to detection of cancers at an earlier clinical stage and detection of lower-grade cancers. If PSA screening is ultimately shown to be beneficial, then appropriate cost-benefit analyses will be required to determine how the shifts in cancer detection rate and cancer stage will affect the economics of serial PSA-based screening.

Aged↗
PubMed1995

Seroprevalence of cysticercosis in an Orthodox Jewish community.

Neurocysticercosis cases were identified in 1991 in an Orthodox Jewish community. Transmission was linked to tapeworm-infected immigrant housekeepers from countries where Taenia solium is endemic. To evaluate the extent of and risks for locally acquired cysticercosis, a seroprevalence survey was conducted in 9% of the households in this community. Cysticercosis antibodies were detected in 23 (1.3%) of 1,789 persons from 612 families. All 23 seropositive persons were asymptomatic, and no intracerebral lesions were found for the 21 seropositive persons who underwent brain imaging. Seropositivity was associated with female sex (relative risk [RR] = 2.45, P = 0.049), hiring a domestic worker for child care duties (RR = 3.79, P = 0.05), and with employees from Central America (RR = 2.70, P = 0.0001). Exposure to T. solium in this community is unexpectedly high. Widespread employment of domestic workers from endemic regions and high employee turnover contributes to exposure risk.

Adolescent↗
PubMed1993

The impact of cancer screening promotion by rural hospitals on cancer detection.

Hospitals almost universally provide health promotion programs for community residents. There is a lack of evidence regarding these programs' impact on the detection or prevention of disease. The purpose of the present study was to determine whether rural hospital-based health promotion programs for cancer screening were associated with detection of greater numbers of cancer cases in the communities served by the hospitals over the years that the promotion programs were offered. Data were collected from a survey of 95 rural Iowa hospitals and from state health registry data on 1985-1990 cancer occurrence. Breast and colon cancer screening promotion programs were related to detection of greater numbers of cases, after controlling for population, age and sex. These findings often held for both less advanced and more advanced cancer stages. Promotion of cervical cancer screening was not related to number of cervical cancers detected. The finding that the relationship between screening promotion and cancer detection persists irrespective of stage may have important policy and programmatic implications.

Adult↗
PubMed2006

Microbial community diversity associated with carbon and nitrogen cycling in permeable shelf sediments.

Though a large fraction of primary production and organic matter cycling in the oceans occurs on continental shelves dominated by sandy deposits, the microbial communities associated with permeable shelf sediments remain poorly characterized. Therefore, in this study, we provide the first detailed characterization of microbial diversity in marine sands of the South Atlantic Bight through parallel analyses of small-subunit (SSU) rRNA gene (Bacteria), nosZ (denitrifying bacteria), and amoA (ammonia-oxidizing bacteria) sequences. Communities were analyzed by parallel DNA extractions and clone library construction from both sediment core material and manipulated sediment within column experiments designed for geochemical rate determinations. Rapid organic-matter degradation and coupled nitrification-denitrification were observed in column experiments at flow rates resembling in situ conditions over a range of oxygen concentrations. Numerous SSU rRNA phylotypes were affiliated with the phyla Proteobacteria (classes Alpha-, Delta-, and Gammaproteobacteria), Planctomycetes, Cyanobacteria, Chloroflexi, and Bacteroidetes. Detectable sequence diversity of nosZ and SSU rRNA genes increased in stratified redox-stabilized columns compared to in situ sediments, with the Alphaproteobacteria comprising the most frequently detected group. Alternatively, nitrifier communities showed a relatively low and stable diversity that did not covary with the other gene targets. Our results elucidate predominant phylotypes that are likely to catalyze carbon and nitrogen cycling in marine sands. Although overall diversity increased in response to redox stabilization and stratification in column experiments, the major phylotypes remained the same in all of our libraries, indicating that the columns sufficiently mimic in situ conditions.

Atlantic Ocean↗
PubMed2001

Diagnosis of influenza in the community: relationship of clinical diagnosis to confirmed virological, serologic, or molecular detection of influenza.

BACKGROUND: Successful treatment of influenza depends on an accurate diagnosis of the illness and prompt intervention. However, there is a lack of data comparing clinical diagnosis vs laboratory diagnostic techniques. OBJECTIVE: To compare the clinical diagnosis of community cases of influenza with various laboratory diagnostic techniques including multiplex, reverse transcription polymerase chain reaction. METHODS: Clinical diagnosis, viral isolation, hemagglutinin inhibition serology, and multiplex, reverse transcription polymerase chain reaction were used to diagnose influenza in patients enrolled in international phase 3 studies designed to investigate the efficacy and safety of an anti-influenza drug (inhaled zanamivir). Patients clinically diagnosed with influenza were enrolled at centers across North America and Europe. RESULTS: A total of 791 (77%) of 1033 patients with laboratory results from all 3 methods were confirmed positive for influenza by 1 or more test results. For 692 patients (67%), the results of all 3 tests agreed. Total symptom scores at baseline showed a significant association toward greater severity of symptoms with an increasing number of positive test results (P<.001). An increasing number of positive test results also showed a significant correlation with a longer time to alleviation of symptoms of influenza in the placebo group (P =.001). CONCLUSIONS: During a time when influenza was known to be circulating and clinical diagnostic criteria were applied, diagnosis of influenza in these trials was accurate in approximately 77% of adults on clinical grounds alone. This highlights the need for primary care physicians to be alerted to circulating influenza and to be aware that presentation with cough and fever provide the most predictive symptoms.

Administration, Inhalation↗
PubMed1977

The Harlem regional stroke program: an overview.

The Harlem regional stroke program has been a demonstration model designed to detect, treat, and follow up stroke and hypertension patients through collaboration with a municipal teaching hospital, community practitioners, local service organizations and a major medical school. Many aspects of the stroke program appear suitable for replication at the local or regional levels in varied settings. In particular, the program has demonstrated the need to link community outreach programs, stressing early detection and preventive-care education, with sustained treatment and follow-up programs. The stroke program has also suggested ways in which specialized programs can be incorporated into long-term comprehensive health planning and care facilities at local and regional levels.

Adolescent↗
PubMedDate not supplied

[Oral health among the Xavánte Indians in Pimentel Barbosa, Mato Grosso, Brazil].

This study presents the results of an oral health epidemiological survey conducted in 1997, based on WHO criteria, in the Xavánte indigenous community of Pimentel Barbosa (or Etéñitépa), Mato Grosso State, Central Brazil. The study included 228 individuals (85% of the population) over two years of age. In about half the sample, the DMF index was less than 2, and in the 12-14-year age bracket it was 3.7. The low frequency of fillings in permanent and deciduous teeth suggests limited access to dental care services. Despite the number of sextants with bleeding and tartar, no cases of severe periodontal disease were detected (CPITN). In the community, comparison of the results of this survey with two previous surveys (1962 and 1991) showed a deterioration in oral health conditions over time and alterations in the occlusal pattern (increase in Angle class II and III). Dietary changes due to environmental and socioeconomic alterations resulting from interaction with the surrounding society, along with the lack of preventive programs, are among the causes of this deterioration in oral health among the Xavánte.

Adolescent↗
PubMed1992

Impact on mortality of a community-based programme to control acute lower respiratory tract infections.

Acute lower respiratory tract infections (ALRIs) are a major cause of death among young children in developing countries. A targeted programme designed to treat children with ALRI was implemented in 1988 in a primary health care project in rural Bangladesh. In the 2 years preceding the introduction of the programme (1986-87), non-ALRI-specific health services were provided, including promotion of oral rehydration therapy, family planning, immunization of children and mothers, distribution of vitamin A, referral of severely sick children to field clinics, and nutritional rehabilitation of malnourished children. The targeted ALRI programme, which was in place in 1988-89, was based on systematic ALRI case detection and management by community health workers, who were linked to a referral system for medical support. These two levels of intervention have been evaluated by comparing the ALRI-specific mortality in the programme area and a neighbouring control area during the two periods. During the first phase (1986-87), the ALRI mortality among under-5-year-olds was 28% lower in the intervention than in the comparison area (P less than 0.01). During the second phase (1988-89), the ALRI mortality was 32% lower in the intervention area than during the preceding phase, while there was no significant difference for the comparison area. These findings suggest that in the study region the combination of specific and nonspecific interventions can reduce ALRI mortality by as much as 50% and the overall mortality among under-5-year-olds by as much as 30%.

Allied Health Personnel↗
PubMed1993

Screening for carriers of Tay-Sachs disease in the ultraorthodox Ashkenazi Jewish community in Israel.

A screening program for the detection of Tay-Sachs disease (TSD) carriers in the ultra Orthodox community of Ashkenazi Jews has operated in Israel since 1986. The purpose of this program is the prevention of marriages of 2 heterozygotes. The screened individuals are mostly couples in the engagement process or students in religious high schools. Two mandatory requirements guide this program. First, anonymity of the tested individuals who are identified only by code numbers; second completion of the test results of couples in the engagement process within a few days. The screening program is performed by the determination of hexosaminidase A (Hex A) activity in serum which is repeated in serum and leukocyte extracts in couples where both partners were found in the heterozygote range in the initial tests. The minimal carrier frequency was estimated to be 1:26 or higher, which is higher then in the general Jewish Ashkenazi population. This higher carrier frequency apparently stems from the fact that most members of this community originate from central Europe where the TSD carrier frequency was previously reported to be the highest in the Ashkenazi population. Since the beginning of the screening program no TSD child has been born to newlywed couples of this community in Israel.

Anonymous Testing↗
PubMed2001

Seroepidemiology of toxoplasmosis in amerindians from western Venezuela.

A survey of 447 Amerindians aged 1-69 years (mean age, 18.6 +/- 15.8 years) in 3 mountain and 1 lowland communities from Venezuela were studied to determine the seroprevalence of Toxoplasma gondii, the environmental risk factors for the infection, and how the process of acculturation may affect the transmission rate. Serum samples were tested for immunoglobulin G antibodies by a commercial indirect hemagglutination test. The overall prevalence of infection was 49.7% (222 of 447) and ranged 38.2-62.4%. A higher antibody rate was found in the lowland setting as compared with those from the mountain area (P < 0.001). The geometric mean titer in the overall population was 280.3. No age-antibody association was detected in the mountain communities, although a gradual increase in positivity with increasing age (P < 0.01) was observed in the lowland setting, reaching a peak of 83.3% in the oldest group. The results suggest that transmission by infective cat feces may play a predominant role in the spread of infection in this population. This study demonstrates the environmental Toxoplasma infection pressure in this sylvatic population and how transmission rate is facilitated by environmental changes produced by acculturation.

Adolescent↗
PubMed1996

Detection of Mycoplasma pneumoniae by polymerase chain reaction in lung aspirates from patients with community-acquired pneumonia.

STUDY OBJECTIVE: This study was designed to evaluate the usefulness of polymerase chain reaction (PCR) to detect Mycoplasma pneumoniae DNA in samples obtained by transthoracic needle aspiration (TNA). DESIGN: Prospective study of cases. SETTING: A university hospital in Lleida, Spain. PATIENTS: A total of 101 unselected patients, admitted between January 1993 and March 1994 in the emergency department, with a clinical and radiologic picture of community-acquired pneumonia, and without contraindications for TNA application. INTERVENTIONS: Patients were studied with conventional diagnostic techniques for community-acquired pneumonia. In addition, a sample obtained by TNA was processed by the following methods: culture in standard media, culture in selective media for Legionella, detection of capsular antigens for Streptococcus pneumoniae and Haemophilus influenzae, and detection of M pneumoniae specific genome by PCR. RESULTS: Serologic data were not available in eight patients and were excluded from this analysis. M pneumoniae PCR amplification was possible in eight cases, well correlated with serologic responses indicating current infection. Samples from ten additional patients, negative by PCR, were found to be demonstrative of recent M pneumoniae infection by serologic study. Finally, in all the remaining 75 cases, including the 59 patients for whom a different microbial diagnosis was established, M pneumoniae PCR test gave negative results. CONCLUSION: This study indicates that PCR, applied to samples obtained by TNA, appears to be a moderately sensitive and highly specific method for rapid detection of M pneumoniae lung infection.

Adult↗
PubMedDate not supplied

Spatial structure and richness of ectomycorrhizal fungi colonizing bioassay seedlings from resistant propagules in a Sierra Nevada forest: comparisons using two hosts that exhibit different seedling establishment patterns.

In this study we analyzed the spatial structure of ectomycorrhizal fungi present in the soils as resistant propagules (e.g. spores or sclerotia) in a mixed-conifer forest in the Sierra Nevada, California. Soils were collected under old-growth Abies spp. stands across approximately 1 km and bioassayed with seedlings of hosts that establish best in stronger light (Pinus jeffreyi) or that are shade-tolerant (Abies concolor). Ectomycorrhizal fungi colonizing the roots were characterized with molecular techniques (ITSRFLP and DNA sequence analysis). Wilcoxina, five Rhizopogon species and Cenococcum were the most frequent of 17 detected species. No spatial structure was detected in the resistant propagule community as a whole, but P. jeffreyi seedlings had higher species richness and associated with seven Rhizopogon species that were not detected on A. concolor seedlings. We drew two conclusions from comparisons between this study and a prior study of the ectomycorrhizal community on mature trees in the same forest: (i) the resistant propagule community was considerably simpler and more homogeneous than the active resident community across the forest and (ii) Cenococcum and Wilcoxina species are abundant in both communities.

Abies↗
PubMed1998

Surveillance data for waterborne illness detection: an assessment following a massive waterborne outbreak of Cryptosporidium infection.

Following the 1993 Milwaukee cryptosporidiosis outbreak, we examined data from eight sources available during the time of the outbreak. Although there was a remarkable temporal correspondence of surveillance peaks, the most timely data involved use of systems in which personnel with existing close ties to public health programmes perceived the importance of providing information despite workload constraints associated with an outbreak. During the investigation, surveillance systems which could be easily linked with laboratory data, were flexible in adding new variables, and which demonstrated low baseline variability were most useful. Geographically fixed nursing home residents served as an ideal population with nonconfounded exposures. Use of surrogate measurements of morbidity can trigger worthwhile public health responses in advance of laboratory-confirmed diagnosis and help reduce total morbidity associated with an outbreak. This report describes the relative strengths and weaknesses of these surveillance methods for community-wide waterborne illness detection and their application in outbreak decision making.

Bias↗