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PubMed1993

A prospective audit of the value of fibre optic bronchoscopy in adults admitted with community acquired pneumonia.

We audited our practice of bronchoscoping patients admitted with community acquired pneumonia to detect latent underlying abnormalities. Fifty-five bronchoscopies were performed immediately after clinical recovery in 64 sequential patients without obvious underlying carcinoma. Five (9.1%) showed abnormalities (four carcinomas and one mild tracheal stenosis). The detection rate of abnormalities and the number of unnecessary bronchoscopies would be improved if only those patients aged 50 years or over who were current or ex-smokers were bronchoscoped. In this group 13.9% (5/36) had an underlying abnormality. The cost implications of such a policy of early bronchoscopy are discussed and compared with traditional follow-up.

Adolescent↗
PubMed2005

The use of directional traps for the assessment of short-term phenanthrene effects upon soil springtail communities.

Directional traps, both horizontal and vertical, were used to assess the behavioural impact of phenanthrene application on soil springtail communities. Avoidance was not detected. Rather, a vertical attraction of the dominant species, Folsomia manolachei, was demonstrated, as well as a decrease in horizontal movements of Lepidocyrtus lanuginosus, another important species mainly captured at the soil surface. Ecological consequences of the results are discussed.

Animals↗
PubMed2005

Effect of petrochemical sludge concentrations on microbial communities during soil bioremediation.

Qualitative and quantitative changes of microbial communities in soil microcosms during bioremediation were determined throughout one year. The soil was contaminated with 0%, 2.5%, 5%, 10% (wt/wt) of petrochemical sludge containing polynuclear aromatic hydrocarbons. We analyzed the hydrocarbon concentration in the microcosms, the number of cultivable bacteria using CFU and most probable number assays, the community structure using denaturing gradient gel electrophoresis, and the metabolic activity of soil using dehydrogenase activity and substrate-induced respiration assays. After one year of treatment, the chemical analysis suggested that the hydrocarbon elimination process was over. The biological analysis, however, showed that the contaminated microcosms suffered under long-term disturbance. The number of heterotrophic bacteria that increased after sludge addition (up to 10(8)-10(9) cells ml(-1)) has not returned to the level of the control soil (2-6 x 10(7) cells ml(-1)). The community structure in the contaminated soils differed considerably from that in the control. The substrate-induced respiration of the contaminated soils was significantly lower (approximately 10-fold) and the dehydrogenase activity was significantly higher (20-40-fold) compared to the control. Changes in the community structure of soils depended on the amount of added sludge. The species, which were predominant in the sludge community, could not be detected in the contaminated soils.

Biodegradation, Environmental↗
PubMed2005

Observation of bias associated with re-amplification of DNA isolated from denaturing gradient gels.

DNA from environmental PCR products separated by denaturing gradient gel electrophoresis (DGGE) was isolated from the background smear rather than from discrete bands of the DGGE gel. The "interband" region was considered as a potential source of less dominant members of natural microbial communities. Surprisingly, instead of detecting new bands from the re-amplified PCR products, patterns very similar to the original ones were obtained regardless of the position of the "interband" region. The results suggest that the separation of amplicons by DGGE may not be perfect and band re-amplification based sequence analyses need careful interpretation.

DNA, Ribosomal↗
PubMed2006

The 5HTTLPR polymorphism of the serotonin transporter gene is associated with affective temperaments as measured by TEMPS-A.

BACKGROUND: Increasing evidence supports the notion of a continuum between affective temperaments and major mood disorders, suggesting that these temperament types represent the subclinical manifestations of affective disorders and often present an increased vulnerability for these diseases. METHODS: The Hungarian rendition of the full-scale 110-item version of the TEMPS-A questionnaire and 5HTTLPR genotype was investigated in a sample of 139 unrelated Caucasian females with no current or lifetime Axis I psychiatric disorders. RESULTS: A significant association was found between the s allele and the TEMPS scores of the depressive, anxious, irritable, and particularly the cyclothymic temperaments; no such association emerged with respect to the hyperthymic temperament. LIMITATION: The database is entirely female. Given that the hyperthymic type predominates in males, our results could have been different if men were included in our sample. CONCLUSIONS: Our results are in good agreement with earlier studies reporting a strong association between the s allele of the 5HTTLPR and major as well as subthreshold forms of depression, and extend this association to the normative temperament level. Indeed, these temperaments might best be regarded as proximate behavioural endophenotypes. Our data raise the provocative possibility that the genetic potential for mood episodes lies in these temperaments. Further studies are needed to delineate the role of gender in the associations under consideration, as well as to investigate the genetic background of the hyperthymia-mania part of the affective spectrum. Given that affective temperaments are widely distributed in the general population, the strategy employed by us is of potential public health significance in terms of detecting individuals in the community at risk for affective spectrum disorders.

Adolescent↗
PubMed1995

Capsular serotypes and antibiotic sensitivity of Streptococcus pneumoniae isolated from primary-school children.

A total of 1049 primary-school children in 18 schools were screened for carriage of Streptococcus pneumoniae. Data on family size, antibiotic use, travel and hospital admissions were collected. Pneumococcal serotyping and sensitivity tests were performed. One third of children were found to be pneumococcal carriers. Ten of 344 isolates were penicillin-resistant (2.9%). Apart from resistance to trimethoprim and ciprofloxacin, resistance rates in penicillin-sensitive strains were low. Among penicillin-resistant strains (PRP), co-resistance to trimethoprim, chloramphenicol and tetracycline was common. Cefotaxime-resistance was seen in 90% of PRP. Although 24 serotypes were represented, groups 6, 19 and 23 accounted for 55% of strains. Serogroup 23 strains were significantly more likely to be penicillin-resistant than other groups/types. Clustering of strains by serotype and antibiotic resistance was seen in several schools. No association with foreign travel, family size or age of siblings was seen and penicillin resistance was not associated with prior antibiotic use. However, hospital admission was significantly associated with carriage of PRP. The implications of detecting PRP in the community are discussed.

Anti-Bacterial Agents↗
PubMed1998

Screening for abdominal aortic aneurysm: is opportunistic detection a realistic alternative?

OBJECTIVES: To determine whether abdominal aortic aneurysms (AAA) may be detected during investigation for concurrent disease and to assess whether opportunistic detection is a feasible alternative to a formal screening programme. DESIGN: A prospective review of previous investigations in subjects attending for aortic screening. MATERIALS AND METHODS: 276 men aged 65-80 attended the Chichester AAA screening programme. They were asked whether they had consulted their General Practitioner and whether they had undergone radiological investigation within the preceding 5 years. RESULTS: Two-hundred and sixty-one subjects had consulted their General Practitioner (94.6%) within the past 5 years. Fifty-six patients had been investigated with radiological imaging: in 22 cases (8.0%) the investigation had the potential to detect an AAA. The opportunistic detection rate was 0.4% (one AAA) in comparison to 12.0% for the screening programme (33 AAA). Imaging investigations with the potential to pick up AAA failed to detect five out of six aneurysms in this group. CONCLUSIONS: Opportunistic screening for AAA is not a realistic alternative to a formal screening programme but may improve the detection rate in the community.

Aged↗
PubMed2003

Genetic and environmental influences on psychological distress in the population: General Health Questionnaire analyses in UK twins.

BACKGROUND: The General Health Questionnaire (GHQ) is the most popular screening instrument for detecting psychiatric disorders in community samples. Using longitudinal data of a large sample of UK twin pairs, we explored (i) heritabilities of the four scales and the total score; (ii) the genetic stability over time; and (iii) the existence of differential heritable influences at the high (ill) and low (healthy) tail of the distribution. METHOD: At baseline we assessed the GHQ in 627 MZ and 1323 DZ female pairs and at a second occasion (3.5 years later) for a small subsample (90 MZ and 270 DZ pairs). Liability threshold models and raw ordinal maximum likelihood were used to estimate twin correlations and to fit longitudinal genetic models. We estimated extreme group heritabilities of the GHQ distribution by using a model-fitting implementation of the DeFries-Fulker regression method for selected twin data. RESULTS: Heritabilities for Somatic Symptoms, Anxiety, Social Dysfunction, Depression and total score were 0.37, 0.40, 0.20, 0.42 and 0.44, respectively. The contribution of shared genetic factors to the correlations between time points is substantial for the total score (73%). Group heritabilities of 0.48 and 0.43 were estimated for the top and bottom 10% of the total GHQ score distribution, respectively. CONCLUSION: The overall heritability of the GHQ as a measure of psychosocial distress was substantial (44%), with all scales having significant additive genetic influences that persisted across time periods. Extreme group analyses suggest that the genetic control of resilience is as important as the genetic control of vulnerability.

Adolescent↗
PubMed2000

Molecular basis of haemoglobinopathies and G6PD deficiency in the Comorian population.

INTRODUCTION: The Comoro archipelago is characterised by a high prevalence of red cell genetic disorders such as G6PD deficiency and haemoglobinopathies, being a region endemic for malaria. Over the last 15 years, the city of Marseilles in France has become the main destination for Comorian immigrants. This Comorian community includes patients with sickle cell disease, sickle cell/beta-thalassaemia trait, thalassaemias and G6PD deficiency. MATERIALS AND METHODS: Allele frequencies for haemoglobin S, beta-thalassaemia and G6PD deficiency were determined from neonatal and prenatal screenings of the Comorian community. Haemoglobin fractions were detected by isoelectrofocalisation, and the quantitation of HbS, HbA, HbA(2) and HbF was performed by cation exchange high performance liquid chromatography. The molecular study involved 31 alleles carrying the betaS mutation (Cd 6 [A-->T]), six beta-thalassaemic alleles and 17 G6PD-deficient alleles, selected from a group of carriers or affected subjects. RESULTS: Allele frequencies were 3% for haemoglobin S, 1% for beta-thalassaemia trait and 9.5% for G6PD deficiency. Molecular analysis had revealed that the African alleles are predominant, being present in almost all the subjects studied. Mediterranean alleles were found for all the beta-thalassaemia mutations and for three G6PD chromosomes out of 17. CONCLUSION: These data are consistent with the mixed Arab and African origin of the population of the Comoro Islands, and are of clinical interest in prenatal and newborn screening plans.

Alleles↗
PubMed2003

Fluctuation of endophytic bacteria and phytoplasmosis in elm trees.

A total of 658 heterotrophic bacterial colonies isolated from phloem tissues of roots and branches in four months (April, June, September and December) from two elm plants, one of which affected by phytoplasmosis, were typed by means of ARDRA. This analysis revealed the existence of a high degree of variability within the community and was able to detect 84 different ARDRA groups. The Analysis of Molecular Variance was applied to ARDRA patterns to analyze the differentiation between communities isolated from the various samplings. Data obtained were compared with those from a previous work (Mocali et al. 2003). Results indicated that plants with symptoms of phytoplasmosis showed marked alterations in the extent of the fluctuations of the community along the seasons in the different plant organs.

Bacteria↗
PubMedDate not supplied

Prioritizing industrial chemical hazards.

This article describes the approach used to develop a prioritized list of toxic and hazardous industrial chemical hazards considered to pose substantial risk to deployed troops and military operations. The U.S. Army Center for Health Promotion and Preventive Medicine published the prioritized list in November 2003. The work was performed as part of a multinational military effort supported by Canada, the United Kingdom, and the United States. Previous chemical priority lists had been developed to support military as well as homeland defense research, development, and acquisition communities to determine enhanced detection and protection needs. However, there were questions as to the adequacy of the methodologies and focus of the previous efforts. This most recent effort is a more extensive evaluation of over 1700 industrial chemicals, with a modified methodology that includes not only the assessment of acute inhalation toxic industrial chemicals (TICs), but also chemicals/compounds that pose substantial physical risk (from fire/explosion) and those that may pose acute ingestion risks (such as in water supplies). The methodology was designed to rank such hazards from a strategic (global) military perspective, but it may be adapted to address more site/user specific needs. Users of this or any other chemical priority list are cautioned that the derivation of such lists is largely influenced by subjective decisions and significant variability in chemical-specific data availability and quality.

Chemical Industry↗
PubMed2026

Probiotic supplementation increases fecal TLR4 agonists without improving disease activity in juvenile idiopathic arthritis: a randomized placebo-controlled trial.

Gut dysbiosis has been implicated in the pathogenesis of juvenile idiopathic arthritis (JIA), suggesting that microbiota-targeted interventions may influence immune signalling during early immune development. We conducted the PERMAJI multicentre randomized, double-blind, placebo-controlled trial to evaluate the effects of probiotic supplementation (VSL#3) on host-microbiota immune interactions and disease activity in children with oligoarticular or RF-negative polyarticular JIA. Participants were randomly assigned (1:1) to receive VSL#3 or placebo for 3 months in addition to standard therapy. Stool and serum samples collected at baseline and month 3 were used to assess gut microbiota composition, fecal innate immune agonists, intestinal permeability, and systemic cytokines. The primary clinical endpoint was the proportion achieving an ACR Pedi 30 response at 3 months. Forty-four children were enrolled between September 2017 and July 2022. Clinical responses did not differ between groups (ACR Pedi 30: 47% with VSL#3 vs 63% with placebo; p = 0.33), and conservative worst-case assumptions for missing data suggested lower response rates with VSL#3 (36% vs 68%; p = 0.03). Probiotic supplementation significantly increased fecal Toll-like receptor 4 (TLR4) agonist activity, whereas gut microbiota diversity, intestinal permeability, and systemic cytokine levels remained unchanged. These findings indicate that probiotic supplementation can modify microbial innate immune signalling without detectable changes in microbial community diversity and may increase exposure to pro-inflammatory microbial stimuli in early-life autoimmune disease. The results highlight the complexity of host-microbiota immune interactions and underscore the need for careful evaluation of microbiome-targeted therapies in paediatric autoimmune disorders.

Humans↗
PubMed2005

Modelling of the mammographic exposure conditions for radiological detriment study in the Valencian Breast Cancer Screening Programme.

Breast screening programmes are the best weapon to fight against breast cancer. Nevertheless, despite the benefits, this practice supposes a radiological risk that cannot be forgotten. In order to calculate breast glandular doses, different MCNP-4C2 models have been developed, simulating the exposure conditions. Radiological detriments have been transported from the population under study in the UNSCEAR 2000 to the Valencian Community, obtaining the detection-induced cancer ratio (DICR) for this population.

Adult↗
PubMed1993

The Texas Breast Screening Project: Part I. Mammographic and clinical results.

The 1987 Texas Breast Screening Project was designed to educate women about the benefits and safety of mammographic screening. During the 2-week promotion, 109,339 women called toll-free telephone numbers to inquire about the program, and 64,459 (65%) of 99,650 eligible callers had $50 mammograms at 306 participating community radiology centers. Biopsies were obtained for 1,122 women (1.7% of those screened), and the ratio of benign to malignant biopsy results was 4.2:1. Among the women having biopsies, 214 cancers were found (3.3 cancers per 1,000 women screened). Forty-seven percent of the tumors were not palpable, 80% were smaller than 2 cm, and 72% were clinicopathologic stage 0 or I. These results show that women will respond to an invitation to attend mammographic screening, and that community radiology centers can detect large numbers of early, curable breast cancers.

Adult↗
PubMed2006

[Synptons of outpatients as data for syndromic surveillance].

OBJECTIVE: To review complaints (such as fever, respiratory symptoms, diarrhea, vomiting, and rashes) in the medical records of outpatients as potential sources of data for syndromic surveillance, and to examine the possibility of practical application from a statistical view point. MATERIALS AND METHODS: Using data obtained from a certain internal and pediatric clinic, we count the number of patients each day who suffered from one of the above five symptoms from January 1st, 2003 to June 30th, 2005. In order to detect outbreaks prospectively after January 1st, 2005, we at first estimate the baseline using the data from January 1st, 2003 to the day before any given day. We then predict the number of patients there ought to be in any given day and judge whether or not an outbreak has occurred. So as to evaluate the system, we check the sensitivity and specificity in its ability to detect outbreaks other than those seen in previous patterns. RESULTS: The total number of cases in which each of the above symptoms occurred were respectively: 11,896 cases of fever, 16,273 cases of respiratory symptoms, 3,672 cases of diarrhea, 3,485 cases of vomiting, and 542 cases of rash. We found prolonged outbreaks of fever and respiratory symptoms in February and March and shorter outbreaks of vomiting and diarrhea in January. The sensitivity and specificity of this system' s ability to detect outbreaks was very high and thus we can confirm that it showed satisfactory performance. DISCUSSION: We found large-scale outbreaks of influenza late in the 2004/2005 season, and small outbreaks of GI that seemed to be particularly related to the Noro virus. In both cases, these outbreaks seemed to be natural phenomena, not artificial, human induced phenomena such as outbreaks caused by bioterrorism attacks. However, since this system was able to detect these outbreaks, we would also be able to use it to detect an outbreak caused by a bioterrorism attack if the size of the outbreak was similar to these cases. CONCLUSION: In order to use this system to detect outbreaks in the community on a smaller level we would have to increase the number of medical institutions cooperating in this study. Moreover, we would need to find a way to handle the different electronic medical record systems and different writing styles used by different medical institutions in order to move toward the practical use of Syndromic Surveillance.

Child↗
PubMed2006

Molecular analysis of arsenate-reducing bacteria within Cambodian sediments following amendment with acetate.

The health of millions is threatened by the use of groundwater contaminated with sediment-derived arsenic for drinking water and irrigation purposes in Southeast Asia. The microbial reduction of sorbed As(V) to the potentially more mobile As(III) has been implicated in release of arsenic into groundwater, but to date there have been few studies of the microorganisms that can mediate this transformation in aquifers. With the use of stable isotope probing of nucleic acids, we present evidence that the introduction of a proxy for organic matter ((13)C-labeled acetate) stimulated As(V) reduction in sediments collected from a Cambodian aquifer that hosts arsenic-rich groundwater. This was accompanied by an increase in the proportion of prokaryotes closely related to the dissimilatory As(V)-reducing bacteria Sulfurospirillum strain NP-4 and Desulfotomaculum auripigmentum. As(V) respiratory reductase genes (arrA) closely associated with those found in Sulfurospirillum barnesii and Geobacter uraniumreducens were also detected in active bacterial communities utilizing (13)C-labeled acetate in microcosms. This study suggests a direct link between inputs of organic matter and the increased prevalence and activity of organisms which transform As(V) to the potentially more mobile and thus hazardous As(III) via dissimilatory As(V) reduction.

Acetates↗
PubMed2000

Culturability and In situ abundance of pelagic bacteria from the North Sea.

The culturability of abundant members of the domain Bacteria in North Sea bacterioplankton was investigated by a combination of various cultivation strategies and cultivation-independent 16S rRNA-based techniques. We retrieved 16S rRNA gene (rDNA) clones from environmental DNAs and determined the in situ abundance of different groups and genera by fluorescence in situ hybridization (FISH). A culture collection of 145 strains was established by plating on oligotrophic medium. Isolates were screened by FISH, amplified ribosomal DNA restriction analysis (ARDRA), and sequencing of representative 16S rDNAs. The majority of isolates were members of the genera Pseudoalteromonas, Alteromonas, and Vibrio. Despite being readily culturable, they constituted only a minor fraction of the bacterioplankton community. They were not detected in the 16S rDNA library, and FISH indicated rare (<1% of total cell counts) occurrence as large, rRNA-rich, particle-associated bacteria. Conversely, abundant members of the Cytophaga-Flavobacteria and gamma proteobacterial SAR86 clusters, identified by FISH as 17 to 30% and up to 10% of total cells in the North Sea bacterioplankton, respectively, were cultured rarely or not at all. Whereas SAR86-affiliated clones dominated the 16S rDNA library (44 of 53 clones), no clone affiliated to the Cytophaga-Flavobacterum cluster was retrieved. The only readily culturable abundant group of marine bacteria was related to the genus Roseobacter. The group made up 10% of the total cells in the summer, and the corresponding sequences were also present in our clone library. Rarefaction analysis of the ARDRA patterns of all of the isolates suggested that the total culturable diversity by our method was high and still not covered by the numbers of isolated strains but was almost saturated for the gamma proteobacteria. This predicts a limit to the isolation of unculturable marine bacteria, particularly the gamma-proteobacterial SAR86 cluster, as long as no new techniques for isolation are available and thus contrasts with more optimistic accounts of the culturability of marine bacterioplankton.

Animals↗
PubMed2003

Culture-independent molecular analysis of microbial constituents of the healthy human outer ear.

Molecular-phylogenetic sequence analyses have provided a new perspective on microbial communities by allowing the detection and identification of constituent microorganisms in the absence of cultivation. In this study we used broad-specificity amplification of ribosomal DNA (rDNA) genes to survey organisms present in the human outer ear canal. Samples were obtained from 24 individuals, including members of three extended families, in order to survey the resident microbiota and to examine microbial population structures in individuals related by familial or household associations. To examine the stability of the microbial populations, one individual was sampled four times and another twice over a 14-month period. We found that a distinct set of microbial types was present in the majority of the subjects sampled. The two most prevalent rDNA sequence types that were identified in multiple individuals corresponded closely to those of Alloiococcus otitis and Corynebacterium otitidis, commonly thought to be associated exclusively with infections of the middle ear. Our results suggest, therefore, that the outer ear canal may serve as a reservoir for normally commensal microbes that can contribute to pathogenesis upon introduction into the middle ear. Alternatively, culture analyses of diseases of the middle ear may have been confounded by these contaminating commensal organisms.

Bacteria↗