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[Quantitative bone ultrasound (QUS) of the heel bone for diagnosis of osteoporosis in the general community].

OBJECTIVE: The aim of the present study was to investigate how quantitative bone ultrasonometry (QUS) can detect patients at risk for osteoporosis in a general community. MATERIAL AND METHODS: 260 women aged 63 +/- 10 were examined using questionnaire, osteological history and QUS (Achilles+). RESULTS: The most frequent osteoporosis risk factors were: no estrogens, no sports and osteoporosis within the family. Risk-patients had lower QUS values compared to persons without risk-factors. There was a negative correlation of ultrasound parameters with age, but not with height or weight. Patients showed a mean loss of body height of -1.2 +/- 1.8 cm versus height in passports, which was positively correlated with QUS. 30% of patients with osteoporosis (T = -2.3 +/- 1.4 SD) had lower QUS than those without (T = -1.4 +/- 1.4 SD). 22% have had a atraumatic fracture (T = -2.5 +/- 1.4 SD), 12 patients had suffered a hip fracture (T = -2.8 +/- 1.8 SD) and 15 patients had a vertebral fracture (T = -2.6 +/- 1.6 SD). Patients on estrogens had T = -1.5 +/- 1.4 SD, which was higher than in those without HRT (T = -2.0 +/- 1.3 SD, p < 0.05). CONCLUSIONS: We conclude from this study that risk patients for osteoporosis can be detected within the community using QUS. QUS is able to detect differences between treated and untreated and can be used in clinical practice to manage patients with osteoporosis risk.

Aged↗

Community-based screening for cardiovascular disease and diabetes using HbA1c.

BACKGROUND: Persons from inner-city immigrant and mixed-ethnic communities are known to be at high risk for cardiovascular disease and diabetes. Such communities may also be underserved for preventive medical care. The authors hypothesized that hemoglobin A1c (HbA1c) could be used as a screening test for a community-based program to detect new cases of diabetes and persons at risk for diabetes and cardiovascular disease. METHODS: Screenings took place in churches, group homes, shelters, community centers, and street corners of the Bronx. Screening data included history of diabetes, age, ethnicity, body mass index, blood pressure, lipid panel, random glucose, and HbA1c. Data were analyzed for number of cases of new diabetes (HbA1c > or =7%), for patients at risk for diabetes (HbA1c 6%-6.99%), and for associations between HbA1c and other variables. The effect of location of screening and self-reported ethnicity on outcome variables was also analyzed. RESULTS: Seven hundred four persons were screened in 25 different sessions. HbA1c and lipid profile were obtained on 539 persons, which formed the cohort for analysis. Mean HbA1c for the cohort was 6.00%. Thirty-two percent of the cohort had HbA1c of more than 6%, and 11.4% had HbA1c of more than 7%. Excluding known diabetics (13% of cohort), 24% had HbA1c of more than 6%, and 3.4% had HbA1c of more than 7%. HbA1c was significantly correlated with total cholesterol, triglycerides, low-density lipoprotein, systolic blood pressure, body mass index, and age; in all cases, correlation coefficients were higher with HbA1c than with random glucose. In addition, significantly higher cardiovascular disease risk factors were found in persons with HbA1c of more than 6%; 6% may be a threshold value for the metabolic syndrome. Mean HbA1c was higher in persons from the South Bronx (which has a higher poverty rate) than the North Bronx (6.08% v 5.74%, p=0.013). There were no statistically significant differences between self-reported ethnic groupings. CONCLUSIONS: There was a high prevalence of undiagnosed diabetes, and of patients at risk for diabetes, in this community setting. Community-based screening can be used as a method for identifying high percentages of patients at risk for diabetes or with undiagnosed diabetes in an inner city, immigrant, mixed-ethnic population.

Adult↗

Dissemination of community-acquired methicillin-resistant Staphylococcus aureus clones in northern Norway: sequence types 8 and 80 predominate.

Increasing frequencies of community-acquired methicillin-resistant Staphylococcus aureus (MRSA) strain isolation have been reported from many countries. The overall prevalence of MRSA in Norway is still very low. MRSA isolates (n = 67) detected between 1995 and 2003 in northern Norway were analyzed by pulsed-field gel electrophoresis, multilocus sequence typing, and staphylococcal cassette chromosome mec (SCCmec) typing. Sixty-seven isolates were associated with 13 different sequence types. Two successful MRSA clones predominated. Sequence type 8 (ST8) (40%) and ST80 (19%) containing SCCmec type IV were detected in hospitals and communities in different geographic regions during a 7-year period. In general, there was a low level of antimicrobial resistance. Only 26% of the isolates were multiresistant. International epidemic clones were detected. The frequent findings of SCCmec type IV (91%) along with heterogeneous genetic backgrounds suggest a horizontal spread of SCCmec type IV among staphylococcal strains in parallel with the clonal spread of successful MRSA strains.

Community-Acquired Infections↗

Autohydrogenotrophic denitrifying microbial community in a glass beads biofilm reactor.

A glass bead biofilm reactor was operated using H2 as an electron donor to remove nitrate at 150 mg NO3-N l(-1) to below detection level. The microbial community in the glass beads biofilm reactor was investigated by using denaturing gradient gel electrophoresis (DGGE) and phylogenetic analysis. In DGGE analysis of the biofilm, five bands were dominant and indicated the presence of eight beta-proteobacteria, one gamma-proteobacteria and twelve clostridia. An unculturable Hydrogenophaga sp., which is a new genus of hydrogen-oxidizing bacterium was dominant in microbial community of the biofilm reactor.

Bacteria↗

Confirmatory analysis for spiramycin residue in bovine muscle by liquid chromatography/particle beam mass spectrometry.

To ensure that residues of veterinary drugs, above their respective maximum residue limits, do not reach the human food supply, European Community regulations specify requirements for detection, quantification and confirmation analytical methods and control procedures. The European Community member states base meat controls on these protocols. A liquid chromatographic/mass spectrometric analysis of spiramycin in calf muscle is presented as a confirmatory method for this compound. A particle beam interface was used, with negative ion chemical ionization mass spectrometry, using methane as the reagent gas. Samples (2 g muscle were prepared by liquid/liquid extraction followed by solid-phase extraction clean-up. On-line liquid chromatography/mass spectrometry of extracts was carried out on a C-18 bonded silica column. The specificity required for a regulatory confirmation procedure was achieved by monitoring five fragment ions with m/z 304, 330, 475, 683 and 684. Variation of the relative ion abundances was less than 20% at the maximum limit of residue, 50 micrograms kg-1. The method specificity was tested for three related compounds: neospiramycin, erythromycin and tylosin. The detection limit based on ion chromatogram peaks areas obtained with control samples was determined to be 20 micrograms kg-1.

Animals↗

Absent or reversed end-diastolic flow in the umbilical artery: outcome at a community hospital.

OBJECTIVE: To describe the peripartum outcome and risk factors for neonatal death among pregnancies complicated with umbilical arterial absent end diastolic or reverse flow (AREDF UA), in a community hospital. STUDY DESIGN: The inclusion criteria of this retrospective analysis were: AREDF UA detected and managed at a community hospital. RESULTS: During the 46 months, 50 cases of AREDF UA were detected and the pregnancies were complicated by hypertensive disease in 52%, twins in 26%, and diabetes mellitus in 14%. Excluding four (8%) stillbirths of non-anomalous fetuses, nine newborns died and the significant differences between those who died and lived (n = 36) were: oligohydramnios (odds ratio [OR] 34.00, 95% confidence intervals [CI] 4.65, 248.50), non-immune hydrops (OR 24.33, 95% CI 1.01, 560.60) and respiratory distress syndrome (OR 7.00, 95% CI 1.27, 38.59). CONCLUSIONS: The risk factors for neonatal mortality with AREDF UA are oligohydramnios, non-immune hydrops, or respiratory distress syndrome.

Blood Flow Velocity↗

A new approach to utilize PCR-single-strand-conformation polymorphism for 16S rRNA gene-based microbial community analysis.

Single-strand-conformation polymorphism (SSCP) of DNA, a method widely used in mutation analysis, was adapted to the analysis and differentiation of cultivated pure-culture soil microorganisms and noncultivated rhizosphere microbial communities. A fragment (approximately 400 bp) of the bacterial 16S rRNA gene (V-4 and V-5 regions) was amplified by PCR with universal primers, with one primer phosphorylated at the 5' end. The phosphorylated strands of the PCR products were selectively digested with lambda exonuclease, and the remaining strands were separated by electrophoresis with an MDE polyacrylamide gel, a matrix specifically optimized for SSCP purposes. By this means, reannealing and heteroduplex formation of DNA strands during electrophoresis could be excluded, and the number of bands per organism was reduced. PCR products from 10 of 11 different bacterial type strains tested could be differentiated from each other. With template mixtures consisting of pure-culture DNAs from 5 and 10 bacterial strains, most of the single strains could be detected from such model communities after PCR and SSCP analyses. Purified bands amplified from pure cultures and model communities extracted from gels could be reamplified by PCR, but by this process, additional products were also generated, as detected by further SSCP analysis. Profiles generated with DNAs of rhizosphere bacterial communities, directly extracted from two different plant species grown in the same field site, could be clearly distinguished. This study demonstrates the potential of the selected PCR-single-stranded DNA approach for microbial community analysis.

Bacteria↗

Detecting comorbid substance misuse among people with schizophrenia in the community: a study comparing the results of questionnaires with analysis of hair and urine.

Substance misuse among people with schizophrenia is thought to be common and to adversely affect the outcome of the illness. The shortcomings of studies in this area include patient samples that are not epidemiologically-based, and methods for detecting substance misuse that have serious limitations. We investigated the frequency and severity of substance misuse among people with schizophrenia living in the community in London. Interviews were conducted with a community-based sample of 39 people with schizophrenia aged 35 years or less, living in Inner London. The assessments included ratings of psychopathology, movement disorders and substance misuse, and co-informant histories. Urine and hair specimens were analysed for a range of substances. Urine samples were collected from 37 patients and hair samples were provided by 36 patients. Comorbid substance misuse was reported or detected in 63% of the sample. The information elicited using a structured questionnaire for both informants and subjects represented an under-estimate of psychostimulant misuse and opiate misuse compared with the results obtained by hair or urine analysis. Hair analysis revealed that 12 (33%) of those patients providing samples had covertly abused amphetamines, opiates or cocaine in the previous 3 months. The study demonstrated that hair analysis is a well-tolerated, sensitive test for substance misuse. The technique has several advantages over questionnaires and urine analysis for clinical and research purposes. Further applications include the assessment of comorbid substance use in particular groups of patients with schizophrenia, such as during first-episode or psychotic relapse, or those with forensic problems or apparent resistance to treatment.

Adult↗

Community prevalence study of taeniasis and cysticerosis in Bail, Indonesia.

Taenia solium, a human cestode parasite endemic throughout most of South-east Asia, causes a number of public health and economic problems. The parasite is endemic in Bali due to a mix of cultural and religious practices. Immunoepidemiological investigation of three rural communities revealed a taeniasis prevalence of 0.72% (3/415). One of the three cases was due to Taenia solium, the other two to Taenia saginata. A further nine cases of Taenia infection were identified from patients from villages surrounding the chosen communities, suggesting that prevalence levels may be higher in other areas. Seroprevalence of human cysticercosis by immunoblot was 1.65% (6/363), though all cases were detected within a single community (6/115; prevalence 5.22%). Several other cases of subcutaneous cysticercosis were identified from local clinics, suggesting continued transmission of Taenia solium in the region. Other intestinal helminth parasites identified within the communities were Ascaris lumbricoides (29.9%), Trichuris trichiuria (33.9%) and hookworm (8.2%).

Adult↗

High rates of multiple antibiotic resistance in Streptococcus pneumoniae from healthy children living in isolated rural communities: association with cephalosporin use and intrafamilial transmission.

OBJECTIVE: Streptococcus pneumoniae is one of the most clinically significant pathogens with emerging antibiotic resistance. We performed a surveillance study in isolated rural populations of healthy children to estimate the prevalence of pneumococcal resistance and to contrast factors that predict pneumococcal carriage with those that specifically predict resistant pneumococcal carriage. METHODS: The study was conducted in 1998 in 2 rural communities in Utah. Families were recruited directly for participation through community canvassing. Surveillance nasopharyngeal cultures were obtained from children who were younger than 8 years. Antibiotic usage and information on other potential risk factors were obtained from questionnaires and local pharmacy records. Resistance was determined by testing isolates for susceptibility to penicillin, cefaclor, trimethoprim-sulfamethoxazole, erythromycin, ceftriaxone, and trovafloxacin. Selected resistant isolates were characterized further by serotyping, pulsed field gel electrophoresis, and Southern blot with DNA probes specific for the pneumococcal lytA gene and for antibiotic resistance genes. RESULTS: In April 1998, surveillance nasopharyngeal cultures were obtained from 368 children aged </=8 years in community A and 369 children in community B. The number of antibiotic courses per child within 1 year before culture was higher in community B than A (mean: 2.2 vs 1.7). Conversely, oral cephalosporins were more frequently used in community A than B (community A: 22% received cephalosporins within 4 months; community B: 12%). Colonization with S pneumoniae was detected in 24% of children in community A and 14% in community B; 36% of isolates from community A and 28% of isolates from community B were resistant or intermediately susceptible to at least 1 antibiotic tested. Reduced susceptibility was most common to trimethoprim-sulfamethoxazole and cefaclor (28% and 26%, respectively). Pneumococcal carriage (susceptible or resistant) was independently associated with age <5 years (odds ratio [OR]: 2.2), child care exposure (OR: 2.4), presence of a sibling with a positive culture (OR: 3.3), and residence in community A (OR: 1.7). Among carriers, age <2 years (OR: 2.6), use of cephalosporins within the preceding 4 months (OR: 2.7), and having a sibling colonized with resistant S pneumoniae (OR: 5.5) were independent predictors of reduced susceptibility or resistance. Each pair of resistant isolates from siblings was indistinguishable by pulsed field gel electrophoresis and other molecular typing techniques. Several pneumococcal isolates from these isolated rural areas had the molecular characteristics of international clones of multiple-drug-resistant pneumococci that have been associated with worldwide spread. CONCLUSIONS: Young age and intrafamilial transmission were important risk factors for carriage of both susceptible and resistant S pneumoniae. In contrast, previous cephalosporin use was linked specifically to resistant pneumococcal carriage, which suggests that modifications in antibiotic usage patterns may have salutary effects on antimicrobial resistance. These results extend previous observations in large cities regarding the penetration of multiple-drug-resistant clones of pneumococci into community populations.

Anti-Bacterial Agents↗

Detection of undiagnosed diabetes and other hyperglycemia states: the Atherosclerosis Risk in Communities Study.

OBJECTIVE: To evaluate screening strategies based on fasting plasma glucose (FPG), clinical information, and the oral glucose tolerance test (OGTT) for detection of diabetes or other hyperglycemic states-impaired fasting glucose (IFG) and impaired glucose tolerance-meriting clinical intervention. RESEARCH DESIGN AND METHODS: We studied 8,286 African-American and white men and women without known diabetes, aged 53-75 years, who received an OGTT during the fourth exam of the Atherosclerosis Risk in Communities Study. Using a split sample technique, we estimated the diagnostic properties of various clinical detection rules derived from logistic regression modeling. Screening strategies utilizing FPG, these detection rules, and/or the OGTT were then compared in terms of both the fraction of hyperglycemia cases detected and the sample fraction receiving different screening tests and identified as screen positive. RESULTS: Screening based on the IFG cut point (> or =6.1 mmol/l), followed by a clinical detection rule for those below this value, detected 86.3% of diabetic case subjects and 66.0% of all hyperglycemia cases, identifying 42% of the sample as screen positive. Applying an OGTT for those positive by the rule provides diagnostic labeling and reduces the fraction that is screen positive to 29%. Another strategy, to apply an OGTT to those with an FPG cut point between 5.6 and 6.1 mmol/l, also identifies 29% of the sample as screen positive, although it detects slightly fewer hyperglycemia cases. CONCLUSIONS: Screening strategies based on FPG, complemented by clinical detection rules and/or an OGTT, are effective and practical in the detection of hyperglycemic states meriting clinical intervention.

Aged↗

[Composition diversity of lactic acid bacteria (LAB) community Al2 used for alfalfa silage].

Alfalfa is the most important forage grass that is difficult to ensile for good quality. Using silage inoculants are the important way for preservation of alfalfa silage. Through continuous restricted subcultivation, a lactic acid bacteria (LAB) community Al2 was selected from well-fermented alfalfa silage. Plate isolation and Denaturing Gradient Gel Electrophoresis (DGGE), construction of 16S rDNA clone library were used to identify the composition diversity of Al2 community, with 7 strains detected, and they were all belonged to Lactobacillus. The composition ratios of the 7 strains were 55.21%, 19.79%, 14.58%, 3.13%, 3.13%, 3.13%, 1.03% according to 16S rDNA clone library. Al2-1i, Al2-2i, Al2-3i, corresponding to L. plantarum (99.9%), L. kimchii (99.4%), L. farciminis (100%) were detected by plate isolation. Among 3 isolates, Al2-1i had the highest ability of dropping pH and producing lactic acid, and the amount of lactic acid was reach to 18g/L at 24h cultivated in MRS media. The ability of dropping pH and producing lactic acid of Al2-3i was the lowest. From DGGE profiles, the dominant strains in Al2 community were L. plantarum and L. kimchii. L. plantarum was detected during the whole process, and L. kimchii was detected in the later phase.

Electrophoresis, Polyacrylamide Gel↗

The relationship between species detection probability and local extinction probability.

In community-level ecological studies, generally not all species present in sampled areas are detected. Many authors have proposed the use of estimation methods that allow detection probabilities that are <1 and that are heterogeneous among species. These methods can also be used to estimate community-dynamic parameters such as species local extinction probability and turnover rates (Nichols et al. Ecol Appl 8:1213-1225; Conserv Biol 12:1390-1398). Here, we present an ad hoc approach to estimating community-level vital rates in the presence of joint heterogeneity of detection probabilities and vital rates. The method consists of partitioning the number of species into two groups using the detection frequencies and then estimating vital rates (e.g., local extinction probabilities) for each group. Estimators from each group are combined in a weighted estimator of vital rates that accounts for the effect of heterogeneity. Using data from the North American Breeding Bird Survey, we computed such estimates and tested the hypothesis that detection probabilities and local extinction probabilities were negatively related. Our analyses support the hypothesis that species detection probability covaries negatively with local probability of extinction and turnover rates. A simulation study was conducted to assess the performance of vital parameter estimators as well as other estimators relevant to questions about heterogeneity, such as coefficient of variation of detection probabilities and proportion of species in each group. Both the weighted estimator suggested in this paper and the original unweighted estimator for local extinction probability performed fairly well and provided no basis for preferring one to the other.

Animals↗

The effect of the "Prestige" oil spill on the plankton of the N-NW Spanish coast.

Chlorophyll, primary production, zooplankton biomass and the species composition of phytoplankton and zooplankton were studied in 2003, after the Prestige shipwreck. The information obtained was compared to previous data series available for the area affected by the spill. A large data series on plankton variables for the N-NW Spanish coast existed, and therefore a realistic evaluation of the effects by comparison with the range of natural variability could be carried out. We emphasized the evaluation of impact during the spring bloom, the first important biological event after the spill. Some minor changes were observed occasionally, but they did not show any clear pattern and were more related to the natural variability of the ecosystem than to effect of the spill. Plankton community structure did not undergo any changes. Only a few species were more abundant during spring 2003 than in previous years. No significant changes were detected in the planktonic community during productive periods, such as the spring bloom and the summer blooms related to intrusions of East North Atlantic Central Waters. The lack of evidence of the effects of the spill on planktonic communities is discussed in terms of the characteristics of the fuel, the high dynamics of the water masses, the biological mechanisms through which the fuel from the surface waters is transferred to the sea floor and, particularly, the influence of the natural variability by means of large and meso-scale hydrographic processes in the area under study. At the present time it is not possible to determine any minor effects the spill may have had on the plankton owing to the great variability of the planktonic cycles and the short-term impact of the oil from the Prestige on the pelagic system.

Animals↗

Colorectal cancer screening with nurse-performed flexible sigmoidoscopy: results from a Canadian community-based program.

BACKGROUND: Despite highest-quality evidence that early detection of colorectal cancer (CRC) can lead to reduced mortality, no organized CRC screening programs exist in Canada. OBJECTIVE: To report the safety, the feasibility, and the detection rate for the first Canadian community-based nurse-performed flexible sigmoidoscopy (FS) screening program for CRC, established in 1999. DESIGN: Cross-sectional analysis of data collected from a prospective study of FS done by nurses from March 1999 to November 2002. Estimate of differences between men and women in FS findings, with relative risks. Logistic regression used to calculate odds ratios for advanced neoplasia. SETTING: Endoscopy suite of a community hospital. PATIENTS: Asymptomatic men and women > or =50 years, with no previous history of CRC. INTERVENTION: FS done by a nurses, and colonoscopy for persons with abnormalities done by an experienced gastroenterologist. MAIN OUTCOME MEASUREMENTS: Mean depth of insertion of endoscope; duration of FS procedure; number and location of polyps found during FS; number, location, and type of polyps found during colonoscopy. RESULTS: A total of 1818 individuals (mean age, 62 years) underwent nurse-performed FS (mean duration, 7.3 minutes; mean depth of insertion of the endoscope, 53.5 cm), without complications. Results of the FS were abnormal for 240 (13.2%) of the 1818 participants; 231 (12.7%) underwent colonoscopy. Distal neoplasms (adenomas or cancer) were detected in 8.7% (158/1818). After adjustment for age and family history of CRC, the risk of advanced neoplasm in the distal colon for men was about twice that for women (odds ratio 1.95, 95% confidence interval 1.21-3.14). Cancer was detected in 5 of the 1818 participants screened (0.28%), and high-grade dysplasia was detected in an additional 5 (0.28%). One of the cancers and all the lesions with high-grade dysplasia were treated endoscopically. CONCLUSIONS: Our community-based nurse-performed FS screening program was feasible and safe. The referral rate for colonoscopy was 13%, and the cancer detection rate was 2.8 per 1000 persons screened.

Aged↗

Detection of genes involved in biodegradation and biotransformation in microbial communities by using 50-mer oligonucleotide microarrays.

To effectively monitor biodegrading populations, a comprehensive 50-mer-based oligonucleotide microarray was developed based on most of the 2,402 known genes and pathways involved in biodegradation and metal resistance. This array contained 1,662 unique and group-specific probes with <85% similarity to their nontarget sequences. Based on artificial probes, our results showed that under hybridization conditions of 50 degrees C and 50% formamide, the 50-mer microarray hybridization can differentiate sequences having <88% similarity. Specificity tests with representative pure cultures indicated that the designed probes on the arrays appeared to be specific to their corresponding target genes. The detection limit was approximately 5 to 10 ng of genomic DNA in the absence of background DNA and 50 to 100 ng of pure-culture genomic DNA in the presence of background DNA or 1.3 x 10(7) cells in the presence of background RNA. Strong linear relationships between the signal intensity and the target DNA and RNA were observed (r(2) = 0.95 to 0.99). Application of this type of microarray to analyze naphthalene-amended enrichment and soil microcosms demonstrated that microflora changed differently depending on the incubation conditions. While the naphthalene-degrading genes from Rhodococcus-type microorganisms were dominant in naphthalene-degrading enrichments, the genes involved in naphthalene (and polyaromatic hydrocarbon and nitrotoluene) degradation from gram-negative microorganisms, such as Ralstonia, Comamonas, and Burkholderia, were most abundant in the soil microcosms. In contrast to general conceptions, naphthalene-degrading genes from Pseudomonas were not detected, although Pseudomonas is widely known as a model microorganism for studying naphthalene degradation. The real-time PCR analysis with four representative genes showed that the microarray-based quantification was very consistent with real-time PCR (r(2) = 0.74). In addition, application of the arrays to both polyaromatic-hydrocarbon- and benzene-toluene-ethylbenzene-xylene-contaminated and uncontaminated soils indicated that the developed microarrays appeared to be useful for profiling differences in microbial community structures. Our results indicate that this technology has potential as a specific, sensitive, and quantitative tool in revealing a comprehensive picture of the compositions of biodegradation genes and the microbial community in contaminated environments, although more work is needed to improve detection sensitivity.

Bacteria↗

Use of a similarity index based on microbial fatty acid (MFA) analysis to monitor biological wastewater treatment systems.

Estimating the stability of microbial community structures may be useful in advanced biological wastewater treatment system design and operation. In this research, a monitoring method using fatty acid profiles was evaluated for detecting changes in microbial community structures. For the evaluation, the operating parameters such as pH, organic loading, and chlorine addition were varied in two identical laboratory scale conventional activated sludge systems. A similarity index based on microbial fatty acid analysis was used to express the stability of microbial community structures in the systems. Experiments using a model microbial community showed that microbial compositions changed daily even under constant operating conditions and that the rate of change increased under dynamic operating conditions. Substrate changes brought about a relatively large change in a microbial community structure, eventually resulting in a very different microbial community. After only 7 days following a substrate change in a lab-scale bioreactor, the biomass exhibited only 45% similarity to the original structure. The analysis of microbial fatty acids conveys additional information, in that it could be used for the calculation of biomass concentrations in a wastewater treatment system if microbial fatty acid analyses are executed on a routine basis as a monitoring tool for biological wastewater treatment systems. The total fatty acid concentrations were about 0.61% of the biomass concentration as mixed liquor volatile suspended solid concentrations in this research.

Bacteria↗

Legionnaires' disease surveillance: England and Wales 1994.

One hundred and sixty cases of legionnaires' disease in England and Wales were reported to the PHLS Communicable Disease Surveillance Centre in 1994, a rate of 3.1 cases per million population. Twenty-seven cases died. Eighty-nine cases (56%) were associated with travel, either in the United Kingdom (UK) or abroad, and six with a stay in hospital; the remaining cases were presumed to have acquired infection in the community. Seven outbreaks were detected in England and Wales: one was associated with a holiday centre, one with a hotel in London, two with industrial sites, and three occurred in the community. A further four clusters were associated with travel abroad: Spain, Ibiza, the Channel Islands, and a Mediterranean cruise. One hundred and twenty-eight of the 160 cases (79%) were sporadic--that is, not known to be associated with outbreaks--43 of which (34%) were not associated with travel nor acquired in hospital.

Adult↗