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PubMed1996

beta-agonists in animal feed. III: Optimization of the clean-up and the end-determination step.

This study represents the second part of an interlaboratory study intended to develop an official modular Community confirmatory method for the detection of beta-agonists in animal feed. Homogeneous pools of primary extracts were prepared by means of an extraction module based on the conclusions of a previous part of this work. The primary extracts were further processed by four laboratories each using a different clean-up scheme. The final extracts thus obtained were cross-distributed between the same laboratories and measured either by GCMS or HPLC. Two laboratories (B and D) applied separate clean-up schemes for clenbuterol and salbutamol. All clean-up schemes for clenbuterol were found to be compatible with all end-determination steps. In contrast, for salbutamol clean-up method D was found not to be compatible with the end-determination steps applied by laboratories B and C. The results of this study have clearly demonstrated that the clean-up methods for both clenbuterol and salbutamol applied by laboratory B yielded superior recoveries with an acceptable standard deviation. Therefore, in conclusion to this study, the participating laboratories recommend the clean-up schemes applied by laboratory B to serve as part of the official Community confirmatory method.

Adrenergic beta-Agonists↗
PubMed2006

Investigating response bias in an information technology survey of physicians.

Monitoring the diffusion of electronic health records (EHR) into ambulatory clinical practice has important policy implications. However, estimates of EHR use are typically derived from survey data and may be subject to significant response bias. The current study is a retrospective analysis testing for response bias in a large information technology survey of physicians (n = 14,921). To detect bias, respondents were compared to nonrespondents on known characteristics. Moreover, early respondents were compared to late respondents with respect to key variables in the survey that are likely to influence participation. The 4203 respondents (28.2% participation rate) did not differ demographically from nonrespondents. Response rates, by specialty, differed slightly. When comparing early and late survey respondents, no differences were detected in EHR use, length of time since EHR installation, practice size, physician age, years since medical school graduation, and years of practice in their current community. Overall, response bias was not detected using established methodologies in this mailed survey of physician EHR use. Similar surveys of physicians, even with a lower than expected response rate, may still be valid.

Adult↗
PubMed1994

Community participation in malaria surveillance and treatment. III. An evaluation of modifications in the Volunteer Collaborator Network of Guatemala.

In most rural areas of Latin America, malaria surveillance and treatment is carried out by a network of unpaid village malaria workers, known as Volunteer Collaborators, who are trained and supervised by the National Malaria Service. To identify ways in which the performance of these volunteer workers could be improved and to test changes that would make the Volunteer Collaborator Networks (VCNs) a more attractive model for community participation in malaria case detection and treatment in other regions, we tested a series of modifications in the VCN of Guatemala. These modifications included improved methods for selecting, supervising, and evaluating the volunteer workers and for collecting blood smears and reporting results, and the use of volunteer workers, known as Volunteer Medicators, who administered presumptive antimalarial therapy without taking a blood smear. A cost-effectiveness analysis of the modified VCN was also carried out. Two years after the modifications were introduced, Volunteer Collaborators identified nearly twice as high a percentage (33% versus 17%) of patients with suspected malaria in their villages. Delays in examining blood smears were reduced from 23 days to 11 days and delays from blood smear examination to curative treatment were reduced from 21 days to 7 days. The Volunteer Medicators identified and treated only a slightly higher percentage of patients than the Volunteer Collaborators (36% versus 33%). However, the cost of maintaining a network of Volunteer Medicators ($0.61 per patient treated) was much lower than the traditional VCN ($2.45) or the modified VCN ($1.85). Thus, with a few, simple and relatively inexpensive modifications, the efficiency and cost-effectiveness of Volunteer Collaborators can be markedly improved. Additionally, the VCN can be modified to make it a more suitable model for community-based malaria control and surveillance networks in other malarious areas of the world, which differ in terms of their level of endemicity, the goals of the malaria program, or the available health care infrastructure.

Community Health Workers↗
PubMedDate not supplied

[Methicillin resistance detection in Staphylococcus aureus: comparison between conventional methods and MRSA-Screen latex agglutination technique].

Methicillin-resistant Staphylococcus aureus (MRSA) is a significant pathogen that has emerged over the last four decades, causing both nosocomial and community-acquired infections. Rapid and accurate detection of methicillin resistance in S. aureus is important for the use of appropriate antimicrobial therapy and for the control of nosocomial spread of MRSA strains. We evaluated the efficiency of conventional methods for detection of methicillin resistance such as the disk diffusion, agar dilution, oxacillin agar screen test, and the latex agglutination test MRSA-Screen latex, in 100 isolates of S. aureus, 79 mecA positive and 21 mecA negative. The MRSA-Screen latex (Denka Seiken, Niigata, Japón), is a latex agglutination method that detects the presence of PLP-2a, product of mecA gene in S. aureus. The PCR of the mecA gene was used as the "gold standard" for the evaluation of the different methods tested. The percentages of sensitivity and specificity were as follows: disk difusión 97 and 100%, agar dilution 97 and 95%, oxacillin agar screen test 100 and 100%, and MRSA-Screen latex, 100 and 100 %. All methods presented high sensitivity and specificity, but MRSA-Screen latex had the advantage of giving a reliable result, equivalent to PCR, in only 15 minutes.

Bacterial Proteins↗
PubMed1994

Voluntary screening program for prostate cancer: detection rate and cost.

In a community-wide screening program conducted in Jacksonville, Florida, 564 participants received free screening for prostate cancer. Frequency of positive results of prostate-specific antigen measurement and digital rectal examination was comparable to that found in similar programs in other communities. The estimated cost for each participant was $231, and the cost to discover each cancer was $7,240. If one also includes initial therapy in cost estimates, then the cost per participant was $520, and the cost to find and treat each patient was $16,300. The value of screening for prostate cancer must be judged by treatment outcome and underlying costs.

Aged↗
PubMedDate not supplied

[Cryptosporidiosis: studies in children in communities of low socioeconomic level].

Cryptosporidium was detected in 2 (1.5%) out of 132 children under 2 years with acute diarrhea; in 2 (3.2%) out of 63 patients under 2 years with persistent diarrhea; in 1 (3.9%) out of 26 malnourished patients younger than 2 years with an episode of acute diarrhea and in 7 (1.4%) out of 516 pediatric ambulatory patients who consulted for acute or chronic diarrhea or recurrent abdominal pain. The clinical histories of the 5 infants with cryptosporidiosis who belonged to the first 3 studies, are presented. All they had prolonged diarrhea (more than 15 days long), and one of them showed low IgG and IgA serum concentrations, but normal proportions of T lymphocyte populations.

Animals↗
PubMed2005

The role of syntrophic associations in sustaining anaerobic mineralization of chlorinated organic compounds.

Stable associations of syntrophic fermentative organisms and populations that consume fermentation products play key roles in the anaerobic biodegradation of chlorinated organic contaminants. The involvement of these syntrophic populations is essential for mineralization of chlorinated aromatic compounds under methanogenic conditions. The fermentative production of low levels of hydrogen (H2) can also be used to selectively deliver a limiting electron donor to dehalogenating organisms and achieve complete dehalogenation of chlorinated aliphatic contaminants such as tetrachloroethene. Thus, tracking the abundance of syntrophically coupled populations should aid in the development and monitoring of sustainable bioremediation strategies. In this study, two complementary nucleic acid-based methods were used to identify and assess relative changes or differences in the abundance of potentially important populations in complex anaerobic microbial communities that mineralized chlorinated aromatic compounds. Population dynamics were related to the consumption and production of key metabolic substrates, intermediates, and products. Syntrophus-like populations were detected in 3-chlorobenzoate-degrading communities derived from sediment or sludge digesters. In the presence of H2-consuming populations, characterized Syntrophus species ferment benzoate, a central intermediate in the anaerobic metabolism of 3-chlorobenzoate and 2-chlorophenol. A DNA probe that targeted characterized Syntrophus species was developed and used to quantify rRNA extracted from the 3-chlorobenzoate- and 2-chlorophenol-degrading communities. The level of rRNA targeted by the Syntrophus-specific probe tracked with the formation of benzoate during metabolism of the parent compounds. Hybridizations with an Archaea-specific probe and/or measurement of methane production demonstrated that methanogens directly benefited from the influx of benzoate-derived electron donors, and the activities of Syntrophus-like and methanogenic populations in the contaminant-degrading communities were closely linked.

Archaea↗
PubMed2002

Functional and structural adaptations of bacterial communities growing on particulate substrates under stringent nutrient limitation.

Biomass recycle reactors (BRRs) were used as a model system to study the functional and structural adaptations of mixed bacterial communities in response to the imposition of increasingly severe nutrient limitation. BRRs were fed synthetic media containing either spinach homogenate or autoclaved yeast cells to simulate the complex mixtures of particulate carbon sources that are often present in nature. In the BRRs fed spinach homogenate, the biomass (measured as particulate protein) exhibited a physiological response similar to previous studies as detected by 40-80% reductions in respiratory potential and by relatively stable catabolic ectoenzyme activities. Concomitant adaptations in bacterial community structure were detected by PCR-DGGE and RT-PCR-DGGE of 16S rDNA and 16S rRNA fragments, respectively. The microbial community structure was dynamic even after the biomass had reached a quasi-steady state with respect to physiological measurements. In the BRRs fed yeast cells, respiratory potentials increased 2- to 5-fold during the initial portion of the BRR run and alpha-glucosidase and beta-glucosidase activities increased 2- to 4-fold. Substantial bacterial community shifts were also detected in both the rDNA and rRNA profiles, indicating that this community was also structurally dynamic. These experiments suggest that phylogenetically different bacteria sustained the functional activities in these ecosystems in response to increasingly stringent nutrient limitation.

Bacteria↗
PubMed1998

Characterization of the dominant and rare members of a young Hawaiian soil bacterial community with small-subunit ribosomal DNA amplified from DNA fractionated on the basis of its guanine and cytosine composition.

The small-subunit ribosomal DNA (rDNA) diversity was found to be very high in a Hawaiian soil community that might be expected to have lower diversity than the communities in continental soils because the Hawaiian soil is geographically isolated and only 200 years old, is subjected to a constant climate, and harbors low plant diversity. Since an underlying community structure could not be revealed by analyzing the total eubacterial rDNA, we first fractionated the DNA on the basis of guanine-plus-cytosine (G + C) content by using bisbenzimidazole and equilibrium centrifugation and then analyzed the bacterial rDNA amplified from a fraction with a high biomass (63% G + C fraction) and a fraction with a low biomass (35% G + C fraction). The rDNA clone libraries were screened by amplified rDNA restriction analysis to determine phylotype distribution. The dominant biomass reflected by the 63% G + C fraction contained several dominant phylotypes, while the community members that were less successful (35% G + C fraction) did not show dominance but there was a very high diversity of phylotypes. Nucleotide sequence analysis revealed taxa belonging to the groups expected for the G + C contents used. The dominant phylotypes in the 63% G + C fraction were members of the Pseudomonas, Rhizobium-Agrobacterium, and Rhodospirillum assemblages, while all of the clones sequenced from the 35% G + C fraction were affiliated with several Clostridium assemblages. The two-step rDNA analysis used here uncovered more diversity than can be detected by direct rDNA analysis of total community DNA. The G + C separation step is also a way to detect some of the less dominant organisms in a community.

Base Composition↗
PubMed2005

Roles of infection control nurses in community hospitals.

OBJECTIVES: To evaluate the roles of infection control nurses (ICNs) and to detect problems, obstacles during work and needs for support in community hospitals. MATERIAL AND METHOD: A descriptive study, data from interview and questionnaire survey of 2 ICN from HA awarded hospitals and 146 IC nurses from hospitals applied for HA. RESULTS: From April to May 2002, questionnaires were returned for 115 (81.56%) plus 7 interviews for a total of 122 samples. The practiced HA IC roles included counseling (86.5%), surveillance (83.1%), administration (82.8%), employee health (82%), education (80%), quality development (76.3%), epidemic investigation (72.2%) and research (10.4%). The major problems and obstacles included inadequate IC knowledge, multiple responsibilities, inadequate cooperation, less administrative support, inadequate budget and documents. CONCLUSION: The present study suggested that the IC research role was the least done because of inadequate knowledge, too heavy work load and lack of administrative support.

Adult↗
PubMed2004

Domestic violence: prevalence and detection in a family medicine residency clinic.

This study was designed to investigate the detection rate of domestic violence by resident physicians in a community-based, primary care training program. Baseline information on detection rates was gathered from residents in the prestudy phase and was compared with data from the 6-month investigation phase of the study, during which a self-administered pencil-and-paper questionnaire on domestic violence was provided to patients and residents. The nursing staff screened new female patients and established patients returning for annual physical examinations. Patients older than 18 years were asked to complete a four-question survey. The examining resident physicians then reviewed the questionnaire answers with patients. During the 6-month prestudy phase, only 7 of 136 patients (5.1%) were determined to be in current (2.9%) or past (2.2%) abusive relationships. Of the 52 patients who completed the investigation phase of the study, 25 (48.1%) reported a lifetime history of abuse, with 9.6% of patients reporting current abuse and 38.5% reporting past abuse. There was a statistical difference regarding history of abuse and lifetime incidence of abuse between the control and study groups. The authors found that routine screening with a few questions could significantly increase detection of domestic violence and enable victims to begin to address their problems. This study has implications for continuing medical education programs as well as residency training programs.

Ambulatory Care Facilities↗
PubMed2006

An Aboriginal-driven program to prevent, control and manage nutrition-related "lifestyle" diseases including diabetes.

Type 2 diabetes and other nutrition-related so-called "lifestyle" diseases, including obesity, and cardiovascular and chronic renal disease, are very prevalent in Australian Aboriginal people and contribute to their high rates of chronic illness and premature mortality. An Aboriginal-driven, community-based health protection, health promotion and improved disease detection, management and care program was introduced in four remote, discrete communities in the far north of Western Australia (WA) in order to attempt to prevent these disorders through community-based lifestyle modification. More energetic screening for early risk factors is involved as well as early dietary and exercise interventions and medical treatment, when indicated. Distinctive features of this program include its Aboriginal initiatives and perspectives, committed partnerships between the communities, the Unity of First People of Australia of Australia (UFPA) and its carers, the communities' health care providers, external clinical specialists, other external agencies and a locally-operated point-of-care (POC) pathology testing capability that is conducted by local and UFPA personnel. The POC component is quality managed by Flinders University. These features have ensured the viability of the program in three of the communities; the other one decided not to continue with the program despite risks of serious long-term health consequences. The pre-program prevalence of diabetes in screened adults was almost 40% and in adults aged (35 years was almost 60%. After several months of the program's operation, there have been positive changes in knowledge about food, nutrition, exercise and disease and altered attitudes and behaviours related to dietary and exercise patterns. There have also been improvements in weight control and in pathology test results relevant to the risk of subsequent development of diabetes and cardiovascular disease.

Adolescent↗
PubMed2003

Prevalence of advanced neoplasia at screening colonoscopy in men in private practice versus academic and Veterans Affairs medical centers.

OBJECTIVES: Several large population studies assessing the yield of average risk screening colonoscopy have evaluated Veterans Affairs (VA) populations. It remains uncertain how generalizable these findings are to men in the general population. The aim of this study was to define the prevalence of advanced neoplasia in male patients undergoing screening colonoscopy in diverse practice settings. METHODS: The Clinical Outcomes Research Initiative (CORI) national endoscopic database was analyzed to compare the findings in men undergoing average risk screening colonoscopy in community, academic, and VA endoscopy settings. RESULTS: Between January, 1998, and May, 2002, a total of 9109 men underwent screening colonoscopy in community (5625), academic (2269), and VA (1215) settings. Overall yield of colonic lesions (mass or polyp >9 mm) on average risk colonoscopy was 5.1%; 5.7% (community), 3.4% (academic), and 5.9% (VA) in each site, respectively. Among patients with lesions identified, multiple lesions >9 mm were less common in academic settings (6.4%) compared to community (12.0%) or VA (8.9%) sites. When adjusting for age and ethnicity on multivariate analysis, colonic lesion detection at VA sites was similar to community settings. However, lesion identification was more likely in both settings (VA: OR = 1.72; community: OR = 1.56) compared to academic centers. CONCLUSIONS: Age- and race-adjusted prevalence of polyps >9 mm in men who receive screening colonoscopy was significantly lower in academic sites compared to VA and community practice sites. One must be cautious in generalizing the findings of male patient studies from academic centers to the entire population.

Academic Medical Centers↗
PubMed1983

Hypertension in the rural population of Bangladesh--a preliminary survey.

A total of 5,026 persons constituting 75% of the total population of a village of Bangladesh were screened for elevated blood pressure. Three hundred thirty seven (6.7%) showed diastolic blood pressure of 90 mm Hg or above. Those with diastolic blood pressure of 95 or above constituted 2% of the population. 74% of the hypertensives were asymptomatic while 86.3% of the cases were undetected and therefore remained untreated. Our findings indicate the need for early detection and control of elevated blood pressure to prevent complications. It is recommended that a large scale community survey programme may be undertaken for detection and early treatment of hypertension which helps prevention of total complications.

Adolescent↗
PubMed2006

Microarray-based analysis of microbial community RNAs by whole-community RNA amplification.

A new approach, termed whole-community RNA amplification (WCRA), was developed to provide sufficient amounts of mRNAs from environmental samples for microarray analysis. This method employs fusion primers (six to nine random nucleotides with an attached T7 promoter) for the first-strand synthesis. The shortest primer (T7N6S) gave the best results in terms of the yield and representativeness of amplification. About 1,200- to 1,800-fold amplification was obtained with amounts of the RNA templates ranging from 10 to 100 ng, and very representative detection was obtained with 50 to 100 ng total RNA. Evaluation with a Shewanella oneidensis Deltafur strain revealed that the amplification method which we developed could preserve the original abundance relationships of mRNAs. In addition, to determine whether representative detection of RNAs can be achieved with mixed community samples, amplification biases were evaluated with a mixture containing equal quantities of RNAs (100 ng each) from four bacterial species, and representative amplification was also obtained. Finally, the method which we developed was applied to the active microbial populations in a denitrifying fluidized bed reactor used for denitrification of contaminated groundwater and ethanol-stimulated groundwater samples for uranium reduction. The genes expressed were consistent with the expected functions of the bioreactor and groundwater system, suggesting that this approach is useful for analyzing the functional activities of microbial communities. This is one of the first demonstrations that microarray-based technology can be used to successfully detect the activities of microbial communities from real environmental samples in a high-throughput fashion.

Bacteria↗
PubMed2003

Bacterial community structure and function in a metal-working fluid.

The diversity of bacterial populations colonizing spatially and temporally separated samples of the same metal-working fluid (MWF) formulation was investigated. Analyses were performed with a view to improve strategies for bioaugmentation of waste MWF in bioreactor systems and prevention of in-use MWF biodeterioration in engineering workshops. Significantly, complementary phenotypic, genotypic and in situ methods revealed that the bacterial communities in operationally exhausted MWFs had low diversity and were similar in species composition from different locations and uses. Of the 179 bacterial isolates studied, only 11 genera and 15 species were identified using fatty acid methyl ester (FAME) analysis, with culture independent analyses by 16S rDNA denaturing gradient gel electrophoresis (DGGE) and fluorescent in situ hybridization being congruent with these FAME data. In order to gain some insight into functional role of detected populations, we correlated the MWF chemical composition and potential pollution load with bacterial abundance and community composition detected within samples.

Bacteria↗
PubMed1995

Colorectal cancer trends by race and anatomic subsites, 1975 to 1991.

OBJECTIVES: To determine whether colorectal cancer rates among black men and women show the abrupt declines seen in whites since the mid-1980s and to determine how the cancer trends vary by anatomic subsites. DATA SOURCES: Mortality data from the National Center for Health Statistics, Hyattsville, Md, and incidence and survival data from the Surveillance, Epidemiology, and End Results program of the National Cancer Institute, Bethesda, Md. MAIN OUTCOME MEASURES: Trends in incidence, survival, and mortality rates. RESULTS: For white men and women, cancer incidence rates declined for the right colon, left colon, and rectum after 1985. Stage-specific incidence rates for white men and women for each subsite had generally similar patterns. Distant-disease incidence rates declined beginning in the late 1970s, whereas regional-disease rates increased until the early to mid-1980s and then declined. An exception is the right colon in men, for which the incidence rates of distant disease did not decline, although the regional-disease pattern was similar to other sites. For blacks, colorectal cancer incidence rates changed little in the 1980s for men or women. In particular, there were no significant declines in the cancer incidence rates of the colorectum or of subsites after 1985. Black colorectal cancer mortality trends showed gender and age differences. Black men had significantly increasing colorectal cancer mortality rates from 1975 through 1992, but the increase after 1985 was observed only in men 65 years of age and older. The colorectal cancer mortality rates did not increase overall in black women in the 1980s, but the mortality rates increased slightly in women 65 years of age and older while declining in women younger than 65 years. CONCLUSIONS: For whites, the trends in colorectal cancer rates by anatomic subsite support the contention that early-detection procedures, such as sigmoidoscopy and colonoscopy, are contributing to the declines in incidence and mortality rates since 1985. The absence in blacks of significant declines in colorectal incidence or mortality rates since 1985 suggests the need for a greater emphasis on early-detection programs in the black community, particularly for elderly blacks.

Black People↗
PubMed1996

Estimating biodegradative gene numbers at a JP-5 contaminated site using PCR.

We have utilized a most-probable-number polymerase chain reaction (MPN-PCR) procedure to estimate gene numbers and biodegradative potential at a jet fuel (JP-5) contaminated site undergoing the first phase of bioremediation. Nucleic acid analysis was used to determine whether a lack of genetic potential for bioremediation was responsible for low levels of oxygen utilization at the site. Total community DNA was extracted and analyzed by PCR for genes (nahAc,alkB, and xylE) known to be involved in the degradation of certain JP-5 constituents. Results indicate that significant aromatic biodegradative potential exists at the site and outlying areas not subjected to engineered remediation, suggesting that physical and/or chemical factors are inhibiting oxygen delivery. xylE and nahAc were often present in significant portions of the microbial community, whereas alkB was rarely detected. This study illustrates the utility of molecular techniques in evaluating biodegradative potential in the field during active bioremediation.

Base Sequence↗