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PubMed2004

Specific response of a novel and abundant Lactobacillus amylovorus-like phylotype to dietary prebiotics in the guts of weaning piglets.

Using 16S rRNA gene-based approaches, we analyzed the responses of ileal and colonic bacterial communities of weaning piglets to dietary addition of four fermentable carbohydrates (inulin, lactulose, wheat starch, and sugar beet pulp). An enriched diet and a control diet lacking these fermentable carbohydrates were fed to piglets for 4 days (n = 48), and 10 days (n = 48), and the lumen-associated microbiota were compared using denaturing gradient gel electrophoresis (DGGE) analysis of amplified 16S rRNA genes. Bacterial diversities in the ileal and colonic samples were measured by assessing the number of DGGE bands and the Shannon index of diversity. A higher number of DGGE bands in the colon (24.2 +/- 5.5) than in the ileum (9.7 +/- 4.2) was observed in all samples. In addition, significantly higher diversity, as measured by DGGE fingerprint analysis, was detected in the colonic microbial community of weaning piglets fed the fermentable-carbohydrate-enriched diet for 10 days than in the control. Selected samples from the ileal and colonic lumens were also investigated using fluorescent in situ hybridization (FISH) and cloning and sequencing of the 16S rRNA gene. This revealed a prevalence of Lactobacillus reuteri in the ileum and Lactobacillus amylovorus-like populations in the ileum and the colon in the piglets fed with fermentable carbohydrates. Newly developed oligonucleotide probes targeting these phylotypes allowed their rapid detection and quantification in the ileum and colon by FISH. The results indicate that addition of fermentable carbohydrates supports the growth of specific lactobacilli in the ilea and colons of weaning piglets.

Animals↗
PubMed2003

Early warning and NHS Direct: a role in community surveillance?

BACKGROUND: NHS Direct is a nurse-led telephone help line that covers the whole of England and Wales. NHS Direct derived data are being used for community surveillance, the purpose of which is to detect a local or national increase in symptoms reported by callers. The system has the potential to identify an increase in symptoms reported by callers about people in the prodromal stages of illness caused by the deliberate release of a biological or chemical agent. There are no other community surveillance projects existing on a national scale that utilize electronic daily data. METHODS: We describe the surveillance system and calls to NHS Direct between December 2001 and July 2002. Confidence limits have been constructed for 10 key algorithms at each site and control charts devised for five of these algorithms at sites covering the key urban areas. RESULTS: Daily reporting has been achieved from NHS Direct sites in England and Wales. High levels of activity in specific algorithms at both national and regional levels have been detected. A sustained national increase in calls about fever occurred in January 2002. CONCLUSION: Although the project is still at an early stage, daily analysis of NHS Direct data has the potential to detect symptoms in the community that could be related to deliberate releases of chemical or biological agents or to outbreaks of disease. For this surveillance to act as an 'early warning' of illness resulting from a microbiological or chemical cause, the NHS Direct surveillance needs to be fully integrated into an appropriate public health response (which may require diagnostic samples to be taken from callers).

Adolescent↗
PubMed2004

Methicillin-resistant Staphylococcus aureus bacteraemia diagnosed at hospital admission: distinguishing between community-acquired versus healthcare-associated strains.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) infections diagnosed at hospital admission are often referred to as community-acquired. This designation may include MRSA strains previously acquired in a healthcare setting (healthcare-associated) as well as those that have emerged from community-based S. aureus strains. METHODS: To understand further the epidemiology of MRSA from the community, a case-control study was performed. During 1997-2002, 254 patients with and without MRSA bacteraemia at hospital admission were studied. RESULTS: All patients with MRSA bacteraemia in the first 24 h of hospital admission had a recent exposure to a healthcare setting: true community-acquired MRSA was not detected. Independent risk factors for healthcare-associated MRSA bacteraemia, defined as MRSA bacteraemia in the first 24 h of hospital admission among patients with a recent exposure to a healthcare setting or intervention, included previous MRSA infection or colonization (OR = 17, P < 0.001), cellulitis (OR = 4, P = 0.006), presence of a central venous catheter (OR = 3, P < 0.001) and skin ulcers (OR = 3, P = 0.007). CONCLUSIONS: In this study, MRSA bacteraemia diagnosed in the first 24 h of hospital admission represented healthcare-associated MRSA strains and not true community-acquired strains. The clinical characteristics associated with healthcare-associated MRSA bacteraemia can assist clinicians in targeting measures to prevent cross-transmission and may help to streamline empirical vancomycin therapy.

Aged↗
PubMed2003

PRISM (Program of Resources, Information and Support for Mothers) Protocol for a community-randomised trial [ISRCTN03464021].

BACKGROUND: In the year after birth one in six women has a depressive illness, and 30% are still depressed, or depressed again, when their child is 2 years old, 94% experience at least one major health problem (e.g. back pain, perineal pain, mastitis, urinary or faecal incontinence), 26% experience sexual problems and almost 20% have relationship problems with partners. Women with depression report less practical and emotional support from partners, less social support overall, more negative life events, and poorer physical health. Their perceptions of factors contributing to depression are lack of support, isolation, exhaustion and physical health problems. Fewer than one in three affected women seek help in primary care despite frequent contacts. METHODS/DESIGN: PRISM aims to reduce depression and physical health problems of recent mothers through primary care strategies to increase practitioners' response to these issues, and through community-based strategies to develop broader family and community supports for recent mothers. Eligible local governments will be recruited and randomised to intervention or comparison arms, after stratification (urban/rural, size, birth numbers, extent of community activity), avoiding contiguous boundaries. Maternal depression and physical health will be measured six months after birth, in a one year cohort of mothers, in intervention and comparison communities. The sample size to detect a 20% relative reduction in depression, adjusting for cluster sampling, and estimating a population response fraction of 67% is 5740 x 2. Analysis of the physical and mental health outcomes, by intention to treat, will adjust for the correlated structure of the data.

Adult↗
PubMed2004

Macroinvertebrate response to acid mine drainage: community metrics and on-line behavioural toxicity bioassay.

The hypothesis is tested that toxicity of acid mine drainage can be detected by a selection of existing macroinvertebrate community and bioindicator metrices supplemented by toxicity tests with the local mosquitofish Gambusia holbrooki Girard and the shrimp Atyaephyra desmaresti Millet. The behavioural responses of A. desmaresti to acid mine drainage were recorded in the Multispecies Freshwater Biomonitor, based on behaviour and survival as parameters. Bioassessment methods were based on community diversity, structure, function, and bioindicators and supplemented by chemical analysis (temperature, pH, metals). The Biological Monitoring Working Party adapted for the Iberian Peninsula, the number of predators (Coleoptera, Hemiptera) and the number of Ephemeroptera and Trichoptera taxa differentiated the sites well. The on-line toxicity test revealed pH-dependent acute toxicity of the acid mine drainage for the shrimp (LC(50)-48 h: pH-AMD=5.8) and a pH- dependent decrease in locomotory activity with the lowest-observed-response-times (LORTs) within 5 h of exposure. Shrimp were more sensitive to acid mine drainage than fish (LC(50)-48 h: pH-AMD=4.9). A new multimetric index combining toxicity testing and bioassessment methods is proposed.

Acids↗
PubMedDate not supplied

Proactive detection of cryptosporidiosis by clinical laboratories. Working Group on Waterborne Cryptosporidiosis.

Laboratories can play a critical and preemptive role as a community's first line of surveillance in detecting waterborne outbreaks when they are aware of increased numbers of stool specimens and suspect or identify Cryptosporidium as the cause of illness. In addition, strong working relationships between clinical laboratories and local or state public health laboratories or agencies can facilitate a meaningful and rapid response related to potential outbreaks. Clinical and public health laboratories potentially play a key role in adding to the limited knowledge of the endemicity and ultimately the natural history of Cryptosporidium. This article addresses the early detection of waterborne outbreaks of cryptosporidiosis and some strategies that could be used to determine endemic levels of Cryptosporidium infections unrelated to outbreaks: to detect Cryptosporidium outbreaks by causes other than potable waterborne sources, e.g., food, surface or recreational waters, pets or farm animals, or sexual contact; or to determine outbreak or endemic levels of other infectious diseases. Strategies for clinical laboratories, which include proactive external and internal planning and a brief overview of laboratory methodologies as they relate to the detection of waterborne cryptosporidiosis, are included.

Clinical Laboratory Techniques↗
PubMed2005

[Molecular analysis of the microbial communities of the Dagang Kongdian flooding bed oilfield].

Both PCR-TGGE (temperature gradient gel electrophoresis, TGGE) and 16S rRNA gene clone library construction were used to comparatively analyze the microbial communities of a water injection well (WW) and an oil well (OW) in Dagang oilfield. TGGE analysis of the PCR amplified 16S rDNA V3 region products showed great difference between these two microbial communities. Six major bands were detected in the TGGE profile of the WW sample, while only one predominant band in the OW sample was found. Two 16S rRNA gene clone libraries were also constructed, and 108 and 50 clones were selected from the WW and OW library respectively for amplified ribosomal DNA restriction analysis (ARDRA). 33 taxanomic operational units (OTUs) were found in the WW library with 6 major OTUs, while only 8 OTUs were found in the OW library with one OTU predominant. The results of TGGE and clone library profiling analysis both indicated that microbial community of the WW had higher diversity than the OW. Sequence analysis of the representative clone of each OTU showed that most bacteria of the WW were affiliated with alpha, beta, and gamma Proteobacteria and Actinobacteria, especially Rhodobacter (47%). Most bacteria of the OW were affiliated with alpha, beta, and gamma Proteobacteria, especially Pseudomonas (62%). Molecular analysis of the microbial diversity in oilfield provides foundation for better application of MEOR (Microbial Enhanced Oil Recovery).

Actinobacteria↗
PubMed2000

Using the Strengths and Difficulties Questionnaire (SDQ) to screen for child psychiatric disorders in a community sample.

BACKGROUND: Child psychiatric disorders are common and treatable, but often go undetected and therefore remain untreated. AIMS: To assess the Strengths and Difficulties Questionnaire (SDQ) as a potential means for improving the detection of child psychiatric disorders in the community. METHOD: SDQ predictions and independent psychiatric diagnoses were compared in a community sample of 7984 5- to 15-year-olds from the 1999 British Child Mental Health Survey. RESULTS: Multi-informant (parents, teachers, older children) SDQs identified individuals with a psychiatric diagnosis with a specificity of 94.6% (95% Cl 94.1-95.1%) and a sensitivity of 63.3% (59.7-66.9%). The questionnaires identified over 70% of individuals with conduct, hyperactivity, depressive and some anxiety disorders, but under 50% of individuals with specific phobias, separation anxiety and eating disorders. Sensitivity was substantially poorer with single-informant rather than multi-informant SDQs. CONCLUSIONS: Community screening programmes based on multi-informant SDQs could potentially increase the detection of child psychiatric disorders, thereby improving access to effective treatments.

Adolescent↗
PubMed1990

Iron in sickle cell disease.

Iron deficiency anaemia was detected in 23% of cases with homozygous sickle cell disease. The aetiology of iron deficiency was similar to the other population in the community. High serum ferritin level was detected in 15.4% of the cases and was well correlated to the number of transfusions. Tissue haemosiderosis was not detected in any case. Patients with heterozygous sickle cell had either normal or low serum ferritin levels.

Adolescent↗
PubMed2002

Impact of age on total and complexed prostate-specific antigen cutoffs in a contemporary referral series of men with prostate cancer.

Age-specific prostate-specific antigen (PSA) cutoffs were previously suggested and were found to miss significant cancers in older men. We assessed the influence of an age-adjusted PSA cutoff to optimize the diagnostic performance (sensitivity and specificity) of complexed PSA (cPSA) and total PSA (tPSA) in the differentiation of benign disease from prostate cancer using a contemporary referral patient cohort. The cPSA and tPSA values were determined using the Bayer Immuno 1 system. The diagnostic utility of tPSA and cPSA was assessed using a diverse contemporary test population consisting of sera prospectively collected between June 1999 and October 2000 from 3597 men who recently underwent a systematic biopsy by urologists in clinical practices throughout the United States. This contemporary patient sample had biopsy diagnoses of either no evidence of malignancy (NEM; N = 2189) or prostate cancer (n = 1408). All serum samples had tPSA values between 2.0 and 20.0 ng/mL. The mean tPSAs (ng/mL) for the NEM and prostate cancer groups were 7.1 +/- 3.2 and 7.3 +/- 3.3, respectively (P = 0.026). The mean cPSAs (ng/mL) for the NEM and prostate cancer groups were 5.6 +/- 2.7 and 6.0 +/- 2.9, respectively (P <0.001). As the tPSA increased from 2.0 to 10.0 ng/mL, the cancer detection rate remained relatively constant at approximately 39% when evaluated using increments of 2.0 ng/mL for tPSA. For fixed sensitivities of 80%, 85%, 90%, and 95%, as the age range increased (45 to 59, 60 to 69, 70 to 79, >or=80), the tPSA and cPSA assay cutoffs required to sustain the specified sensitivity level markedly increased, with the exception of the 95% sensitivity level, where the cutoffs only slightly increased between the age ranges of 45 to 69 and >or=70. Overall, cPSA showed a marginal improvement in specificity versus tPSA across all age groups at all sensitivity levels. In this community referral population, the cancer detection rate remained fairly constant over the tPSA range of 2.0 to 20.0 ng/mL. This study demonstrated that to maintain a given sensitivity level for cPSA and tPSA in the age ranges studied, continuous upward adjustment of the cutoffs was required as age increased.

Age Factors↗
PubMed2004

Investigation of bacterial communities associated with asymptomatic and symptomatic endodontic infections by denaturing gradient gel electrophoresis fingerprinting approach.

The purpose of the present study was to investigate the bacterial communities associated with asymptomatic and symptomatic endodontic infections and to compare denaturing gradient gel electrophoresis (DGGE) fingerprinting patterns of these two clinical conditions. The root canal microbiota of teeth associated with asymptomatic or symptomatic periradicular lesions was profiled by the PCR-DGGE method and then compared, taking into consideration the banding patterns. Bacteria were present in all examined cases. Comparative analysis of the two clinical conditions revealed bands that were common to both symptomatic and asymptomatic cases, but most DGGE bands appeared to be unique for each clinical condition. No single band occurred in all profiles. The mean number of bands detected in the 16S rDNA community profiles were 12.1 +/- 9.4 (range 2-29) for symptomatic samples and 6.7 +/- 2.7 (range 2-11) for asymptomatic ones. Clustering methods and principal component analysis of DGGE banding pattern placed the samples according to the presence or absence of symptoms. Four intense bands that were excised from the gel and sequenced showed similarities to species of the Campylobacter genus (found in 5/12 asymptomatic and in 3/11 symptomatic cases), Fusobacterium genus (4/11 symptomatic cases), Acinetobacter genus (5/12 asymptomatic cases), and Enterobacteriaceae family (11/12 asymptomatic and 2/11 symptomatic cases). The profiles of the predominant bacterial community appeared to be unique for each individual. These findings confirm that endodontic infections are polymicrobial and showed that there are significant differences in the predominant bacterial composition between asymptomatic and symptomatic cases.

Acinetobacter↗
PubMed1991

Community acquired pneumonia caused by Chlamydia pneumoniae strain TWAR in chronic cardiopulmonary disease in the elderly.

The role of Chlamydia pneumoniae in respiratory infections is controversial. Seroepidemiological studies in different countries have shown an incidence of around 50% of previous contact, whereas prospective studies only in the USA have detected 6-10% of C. pneumoniae in community acquired pneumonias; in a similar Swedish study no cases were detected. There have been no descriptions of this Chlamydia in Mediterranean countries. The acute antibody response indicative of recent infection is accepted if the microimmunofluorescence test shows a fourfold rise in antibody or a titer 1/6 or higher of the IgM fraction. Since the introduction of the microimmunofluorescence test in our hospital, we have detected 4 cases of pneumonia associated to TWAR antibody in a current study of 63 cases of community acquired pneumonias which required hospitalization. All 4 patients presented chronic cardiopulmonary diseases. These facts and additional seroepidemiological studies with a frequency of 53% of previous contact, show that C. pneumoniae has a nonrare etiology in Spain and could be an endemic condition.

Aged↗
PubMed1989

Measuring change in nutritional status: a comparison of different anthropometric indices and the sample sizes required.

The usefulness of different anthropometric indices to detect nutritional changes at the community level, ie, in a number of children considered as a group, was compared by using data from a longitudinal study from rural Bangladesh which followed up quarterly an average of 413 children aged 6-35 months from December 1984 to December 1987. Weight change, mid-upper arm circumference and weight-for-height responded most quickly to seasonal variations of the food situation. Height-for-age was more responsive to long-term variations. Although similar conclusions were reached when proportions of children below a cut-off point or mean indices were compared, the comparison of mean indices required a smaller sample size to detect changes. The difference in sample size needed ranged from 48 to 61 per cent. All indices varied significantly with age, which suggests that precise knowledge of age is essential for proper interpretation of nutritional surveillance data.

Aging↗
PubMed2002

Functional analysis of microbial communities in aerobic-anaerobic sequencing batch reactors fed with different phosphorus/carbon (P/C) ratios.

Fluorescence in situ hybridization (FISH) was used to analyse the community composition of a sequencing batch reactor (SBR) operating with aerobic-anaerobic cycling and fed acetate as its sole carbon source. Phosphorus was removed from the SBR microbiologically. Marked shifts in the community structure occurred as the phosphorus/carbon (P/C) ratio in the feed was changed. When the P/C ratio was shifted from 1:10 to 1:50, FISH analysis showed that the percentage of beta-Proteobacteria fell from ca 77% of the total bacteria to ca 38%. This decrease in the beta-Proteobacteria coincided with a reduction in both the proportions of the beta-proteobacterial Rhodocyclus-related phosphorus-accumulating bacteria and the biomass phosphorus content. FISH/microautoradiography and FISH/poly beta-hydroxyalkanoate (PHA) staining showed that the Rhodocyclus-related bacteria assimilated acetate and synthesized PHAs anaerobically, and that they accumulated phosphorus aerobically. No Acinetobacter spp. could be detected in any of the communities, casting further doubt on their role in phosphorus-removing activated sludge systems. As the feed P/C ratio decreased there was a corresponding increase in the proportion of alpha-Proteobacteria and, to a smaller extent, in the proportion of gamma-Proteobacteria; both the alpha- and gamma-Proteobacteria consisted mostly of tetrad-forming cocci, fitting the description of the so-called 'G-bacteria' morphotype. The change in the proportions of Proteobacteria present paralleled increases in the biomass glycogen content. Both the alpha- and beta-proteobacterial 'G-bacterial' populations assimilated acetate and synthesized PHA anaerobically. The alpha-Proteobacteria are considered responsible for glycogen production in these SBR systems.

Bacteria, Aerobic↗
PubMed2003

Copper-induced modifications of the trophic relations in riverine algal-bacterial biofilms.

The effects of copper (Cu) on photosynthetic riverine biofilms were studied in artificial stream channels. Direct effects on the composition and functioning of the biofilms were investigated using plant pigments, community-level physiological profiles (CLPP), and pulse-amplitude-modulated (PAM) fluorescence. Copper caused a significant reduction of microalgal biomass and induced a shift in the population from diatoms to cyanobacteria. However, a decrease in biomass indicated that the replacement of species was not totally effective to counteract the toxic effects of Cu. A direct effect of Cu could also be shown in the bacterial community, and, furthermore, changes in the CLPP could be related to the Cu treatment. Copper-exposed biofilms lost the capacity to use between 11 and 15% of the substrates, but many of the remaining capacities became more robust, indicating an increased Cu tolerance due to the exposure. The change in the biofilm microbial composition points to the indirect effects of Cu on biofilms due to the close interdependence between biofilm autotrophic and heterotrophic compartments. Grazing by snails, which appeared to be an important factor structuring biofilms without any Cu addition, had a very minor effect on Cu-exposed biofilms. Although grazing changed the bacterial composition, its effects were not detected either on the algal community or on the biofilm community tolerance to Cu.

Bacteria↗
PubMed1991

The role of the hepatitis delta virus in acute hepatitis and in chronic liver disease in Greece.

HDV infection has been documented in Greece for more than 3 decades. Its epidemiology appears to be changing over the years with a decrease in the general Greek population and an invasion of the delta virus in the community of drug addicts. For the time being HDV infection has a low endemicity in the general greek population, it has been detected with high endemicity in a rural community and it is spreading epidemically in the new, increasing population of Greek drug addicts. Chronic HDV infection has been detected constantly over 20 years with a higher frequency in HBsAg positive chronic liver disease (19.5-33.5%) than in asymptomatic HBsAg carriers with normal liver enzymes (5.9-9.2%). However, in the community of Archangelos, where HDV infection is highly endemic, and probably also all over Greece, the total number of chronic HDV carriers with minimal or no liver disease appears to be higher than those with severe liver damage. HDV infection plays a significant role in terms of morbidity and mortality from acute and chronic liver disease in Greece but the situation would have been much worse if chronic HDV infection was invariably associated with severe liver damage.

Acute Disease↗
PubMedDate not supplied

Prevalence of human herpesvirus 6 antibody among isolated Amazonian Amerindian communities in Brazil.

Human herpesvirus 6 (HHV6) antibody was detected by the anticomplement immunofluorescence test in 65 of 592 serum samples (10.9%) obtained from Amerindians belonging to 4 remote communities inhabiting the Amazon Region of Brazil. Seropositivity rates ranged from 5.4% in the Oyampí to 14.9% in the Tucano. Among the Mekranoiti and Tiriyo, the seroprevalence rates were 12.5% and 11.8%, respectively. In children aged 0-10 years, the prevalences of HHV6 antibody ranged from 5.2% to 24.2%, among the Oyampí and Mekranoiti tribes, respectively. In the 11-20 and > 20 years old age groups, percentages of positivity ranged, in the former group, from 9.5% to 17.5% in the Oyampí and Tucano, respectively and, in the latter group, from 1.3% in the Oyampí to 14.8% in the Tucano. The prevalences of HHV6 antibody decreased regularly through the first 3 age-groups in the Mekranoiti and Tiriyo. In addition, frequencies of seropositivity were consistently higher in males than in females in the Mekranoiti (P < 0.05), Oyampí and Tiriyo tribes.

Adolescent↗
PubMed1990

Epidemiology of mood disorders: a community survey in Florence.

A structured interview designed to detect affective disorders and to produce both DSM-III and DSM-III-R diagnoses was administered to a community sample of 1000 people living in Florence. The interviews were carried out by physician-psychiatrists (qualified psychiatrists or 3rd-4th-year trainees) trained in the use of operational diagnoses. The 1-year prevalence and point prevalence were, respectively: 1.7% and 0.6% for bipolar disorder; 0.4% and 0.4% for cyclothymia; 6.2% and 2.8% for major depression; 2.6% and 0.8% for dysthymia; 5.2% and 1.8% for depressive disorder not otherwise specified. Most of the cases affected by mood disorder sought medical help, primarily through their GP. The large majority of them were specifically treated for it and, in almost 60% of the cases with a major form, were referred to a psychiatrist.

Adolescent↗