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PubMed2005

Clinical and neuroimaging correlates of mild cognitive impairment in a middle-aged community sample: the personality and total health through life 60+ study.

This cross-sectional study aimed at determining the clinical and structural brain magnetic resonance imaging correlates of mild cognitive impairment (MCI). The data presented here are from the first wave of the longitudinal Personality and Total Health through Life 60+ project. 2,551 community-dwelling individuals in the age range of 60-64 years were recruited randomly through the electoral roll. They were screened using Mini-Mental State Examination and a short cognitive battery. Those who screened positive underwent detailed medical and neuropsychological assessments. Of the 224 subjects who screened positive, 117 underwent a detailed assessment. Twenty-nine subjects fulfilled the Mayo Clinic criteria for MCI. Magnetic resonance imaging scans were analyzed for 26 subjects with MCI as well as normal controls. Subjects were clinically evaluated for depressive symptoms and major and minor depression syndromes. Logistic regression analysis was performed predicting MCI from anterior and mid-ventricular brain ratios, cortical atrophy measures, hippocampal volumes, volumes of amygdala and white matter hyperintensities after adjusting for age, gender, years of education, depression and physical disability. None of the neuroanatomical substrates appeared as predictors of MCI. The only predictors were higher depression scores and fewer years of education. Structural neuroimaging may not have an added advantage in the detection of MCI in middle-aged community-dwelling subjects. It may be that this age group is too young for such brain changes to be identified.

Amygdala↗
PubMed1998

Foraging bumblebees avoid flowers already visited by conspecifics or by other bumblebee species

Honey bees, Apis mellifera, use short-lived repellent scent marks to distinguish and reject flowers that have recently been visited by themselves or by siblings, and so save time that would otherwise be spent in probing empty flowers. Conversely, both honey bees and bumblebees, Bombus spp., can mark rewarding flowers with scent marks that promote probing by conspecifics. We examined detection of recently visited flowers in a mixed community of bumblebees foraging on comfrey, Symphytum officinale, in southern England. When foraging among inflorescences on a plant, three abundant species of Bombus probed fewer inflorescences more than once than would be expected from random foraging. Bees frequently encountered inflorescences but departed without probing them for nectar. Examination of the incidence of such rejections in the two most common species, B. terrestris and B. pascuorum, revealed that the low incidence of multiple probing visits was due to two factors: bees both foraged systematically and selectively rejected inflorescences that they had previously visited. When presented with inflorescences of known history, bees selectively rejected those that had been recently visited by themselves or by conspecifics compared with randomly selected inflorescences. They were also able to distinguish inflorescences that had been visited by other Bombus species. Bees were unable to distinguish and reject inflorescences from which the nectar had been removed artificially. We conclude that these Bombus species are probably using scent marks left by previous visitors. The significance of deposition and detection of interspecific scent marks for competitive interactions between species is discussed. Copyright 1998 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed2006

Rhinovirus chemotherapy.

Human rhinoviruses (HRV), members of the Picornaviridae family, are comprised of over 100 different virus serotypes. HRV represent the single most important etiological agents of the common cold [Arruda, E., Pitkaranta, A., Witek Jr., T.J., Doyle, C.A., Hayden, F.G., 1997. Frequency and natural history of rhinovirus infections in adults during autumn. J. Clin. Microbiol. 35, 2864-2868; Couch, R.B., 1990. Rhinoviruses. In: Fields, B.N., Knipe, D.M. (Eds.), Virology. Raven Press, New York, pp. 607-629; Turner, R.B., 2001. The treatment of rhinovirus infections: progress and potential. Antivir. Res. 49 (1), 1-14]. Although HRV-induced upper respiratory illness is often mild and self-limiting, the socioeconomic impact caused by missed school or work is enormous and the degree of inappropriate antibiotic use is significant. It has been estimated that upper respiratory disease accounts for at least 25 million absences from work and 23 million absences of school annually in the United States [Anzueto, A., Niederman, M.S., 2003. Diagnosis and treatment of rhinovirus respiratory infections. Chest 123 (5), 1664-1672; Rotbart, H.A., 2002. Treatment of picornavirus infections. Antivir. Res. 53, 83-98]. Increasing evidences also describe the link between HRV infection and more serious medical complications. HRV-induced colds are the important predisposing factors to acute otitis media, sinusitis, and are the major factors in the induction of exacerbations of asthma in adults and children. HRV infections are also associated with lower respiratory tract syndromes in individuals with cystic fibrosis, bronchitis, and other underlying respiratory disorders [Anzueto, A., Niederman, M.S., 2003. Diagnosis and treatment of rhinovirus respiratory infections. Chest 123 (5), 1664-1672; Gern, J.E., Busse, W.W., 1999. Association of rhinovirus infections with asthma. Clin. Microbiol. Rev. 12 (1), 9-18; Pitkaranta, A., Arruda, E., Malmberg, H., Hayden, F.G., 1997. Detection of rhinovirus in sinus brushings of patients with acute community-acquired sinusitis by reverse transcription-PCR. J. Clin. Microbiol. 35, 1791-1793; Pitkaranta, A., Virolainen, A., Jero, J., Arruda, E., Hayden, F.G., 1998. Detection of rhinovirus, respiratory syncytial virus, and coronavirus infections in acute otitis media by reverse transcriptase polymerase chain reaction. Pediatrics 102, 291-295; Rotbart, H.A., 2002. Treatment of picornavirus infections. Antivir. Res. 53, 83-98]. To date, no effective antiviral therapies have been approved for either the prevention or treatment of diseases caused by HRV infection. Thus, there still exists a significant unmet medical need to find agents that can shorten the duration of HRV-induced illness, lessen the severity of symptoms, minimize secondary bacterial infections and exacerbations of underlying disease and reduce virus transmission. Although effective over-the-counter products have been described that alleviate symptoms associated with the common cold [Anzueto, A., Niederman, M.S., 2003. Diagnosis and treatment of rhinovirus respiratory infections. Chest 123 (5), 1664-1672; Gwaltney, J.M., 2002a. Viral respiratory infection therapy: historical perspectives and current trials. Am. J. Med. 22 (112 Suppl. 6A), 33S-41S; Turner, R.B., 2001. The treatment of rhinovirus infections: progress and potential. Antivir. Res. 49 (1), 1-14; Sperber, S.J., Hayden, F.G., 1988. Chemotherapy of rhinovirus colds. Antimicrob. Agents Chemother. 32, 409-419], this review will primarily focus on the discovery and development of those agents that directly or indirectly impact virus replication specifically highlighting new advances and/or specific challenges with their development.

Antiviral Agents↗
PubMed2005

Frequent carriage of Panton-Valentine leucocidin genes by Staphylococcus aureus isolates from surgically drained abscesses.

Between 1 February and 15 April 2002, 95 patients were admitted to Gaston Bourret Territorial Hospital (New Caledonia, France) for drainage of community-acquired soft tissue abscesses. Staphylococcus aureus was detected in 68 cases (72%). Two-thirds of the patients with S. aureus infection had furuncles, which were located on the limbs in 82% of cases. The median interval between symptom onset and hospital admission was 5.7 days. Three-quarters of the patients were Melanesians living in tribes. Fifty-four S. aureus isolates were screened for toxin genes. Panton-Valentine leucocidin (PVL) genes were detected in 48 isolates (89%), the exfoliative toxin A gene was detected in 1 isolate, and no toxin genes were detected in 4 isolates. S. aureus nasal carriage was detected in 39.7% of patients with S. aureus infections. Two infecting S. aureus strains and two nasal carriage strains were resistant to methicillin. Comparative pulsed-field gel electrophoresis, performed in 16 cases, showed that five of six patients with PVL-positive nasal carriage strains were infected by the same strains. In contrast, 8 of 10 patients with PVL-negative nasal carriage strains were infected by PVL-positive strains. PVL genes thus appear to be a major virulence factor in both primary and secondary S. aureus skin infections.

Abscess↗
PubMed2004

Predominance and genetic diversity of community- and hospital-acquired CTX-M extended-spectrum beta-lactamases in York, UK.

OBJECTIVES: This study was conducted to detect the presence of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae within the faecal flora of both community- and hospital-based patients in York and to characterize the bla(TEM), bla(SHV) and bla(CTX-M) genes present in these isolates. METHODS: One thousand faeces samples were collected and screened at York Hospital during October-December 2003. Ninety-five non-duplicate Enterobacteriaceae isolates resistant to third-generation cephalosporins were recovered; 22 isolates were selected for further study on the basis of a positive double disc diffusion test for ESBL production. Antibiotic susceptibility testing was performed to a range of antibiotics. The TEM, SHV and CTX-M genes were detected by PCR and the DNA sequenced. RESULTS: The distribution of ESBL-positive isolates from the hospital and community was 1.4:1. These included nine Escherichia coli, seven Enterobacter cloacae, four Citrobacter freundii and a single isolate each of Klebsiella spp. and Salmonella spp. A total of 17 isolates contained bla(CTX-M) (five bla(CTX-M-15), three bla(CTX-M-14) and nine bla(CTX-M-9)). ISEcp1 was present in isolates expressing CTX-M-14 and -15, but was absent upstream of In60-associated bla(CTX-M-9). E. coli isolates also contained either a bla(TEM-1) or bla(TEM-2), whereas six of the E. cloacae carried bla(SHV-12) and the Klebsiella spp. bla(SHV-36) in addition to bla(CTX-M-9). The single Salmonella spp. carried bla(SHV-12). CONCLUSIONS: The overall prevalence of ESBL in isolates of Enterobacteriaceae from York was 1.9%. ESBL-producing isolates were found in both the community and hospital, with the CTX-M type most common. This is also the first report of an ESBL-producing Salmonella in the UK.

Community-Acquired Infections↗
PubMed2005

Comparison of non-invasive sampling methods for detection of HPV in rural African women.

BACKGROUND: The prevalence of cervical cancer is extremely high in low income countries, primarily because of a lack of cytological screening. The link between human papillomavirus (HPV) and cervical cancer has long been recognised, and it has been suggested that isolated HPV testing in women who do not participate in existing screening programmes may be used to identify women at higher risk of developing cervical cancer. This community based study compares two self administered techniques for detecting HPV (tampons and self administered swabs) with a clinician directed technique, the cervical cytobrush. METHODS: 377 rural women were interviewed and of these 210 women had full gynaecological examination, and accepted all three sampling methods for HPV. HPV typing of DNA extracts was performed using polymerase chain reaction and enzyme linked immunosorbent assay techniques. RESULTS: Using the cervical cytobrush as the gold standard, self administered swabs (SAS) showed a sensitivity of 63.9%, and tampons showed a sensitivity of 72.4%. The acceptability of these two tests was 97.1% and 84.6% respectively. When combining acceptability with sensitivity, the SAS detected 61.9% and the tampons detected 60.9% of the true positives. CONCLUSION: In a setting where women are at a considerable risk of developing cervical cancer, with no access to a formal screening programme, self directed HPV testing could be a useful screening tool in identifying those women at increased risk who may require further investigation.

Enzyme-Linked Immunosorbent Assay↗
PubMed1987

Negative conversion of COP (circumoval precipitation) reactions after selective mass chemotherapy on schistosomiasis japonica with praziquantel in Bohol, Philippines.

For the longitudinal survey of human schistosomiasis japonica in the villages of Sto. Tomas and San Vicente in the province of Bohol, Philippines, the circumoval precipitin (COP) test was used for case detection. Plasma collected by finger prick from the community people and lyophilized eggs of Schistosoma japonicum were used for the assay. Degree of precipitation at type 2 or 3 of Yokogawa et al. [1] was considered as positive. Selective mass chemotherapy with praziquantel was given to the patients including cases with only positive COP reactions. San Vicente and Sto. Tomas villages were examined in 1984 and 1982, respectively and followed up in 1986. Positive COP reactions were converted to negative in 82.1% or 55 out of 67 cases treated in 1984 and 1985 at San Vicente. Similarly, negative conversion was observed in 75.4% or 43 out of 57 cases treated in 1981 and 1982 at Sto. Tomas. The cases with persistent positive COP reaction after treatment were considered as incomplete cure or reinfection. The concentrated distribution of positive cases around the habitat of Oncomelania snails was observed at San Vicente where the prevalence of COP positives declined from 22.2% to 14.0% in 2 years. These results suggest that in the area with selective mass chemotherapy on schistosomiasis japonica, COP reactions of treated cases are converted to negative at high proportions in 2 years, and the positives detected by subsequent survey after 2 years are considered mostly as new infections or reinfections.

Animals↗
PubMed2000

Detection of Legionella species in respiratory specimens using PCR with sequencing confirmation.

Legionella spp. are a common cause of community-acquired respiratory tract infections and an occasional cause of nosocomial pneumonia. A PCR method for the detection of legionellae in respiratory samples was evaluated and was compared to culture. The procedure can be performed in 6 to 8 h with a commercially available DNA extraction kit (Qiagen, Valencia, Calif.) and by PCR with gel detection. PCR is performed with primers previously determined to amplify a 386-bp product within the 16S rRNA gene of Legionella pneumophila. We can specifically detect the clinically significant Legionella species including L. pneumophila, L. micdadei, L. longbeachae, L. bozemanii, L. feeleii, and L. dumoffii. The assay detects 10 fg (approximately two organisms) of legionella DNA in each PCR. Of 212 clinical specimens examined by culture, 100% of the culture-positive samples (31 of 31) were positive by this assay. By gel detection of amplification products, 12 of 181 culture-negative samples were positive for Legionella species by PCR, resulting in 93% specificity. Four of the 12 samples with discrepant results (culture negative, PCR positive) were confirmed to be positive for Legionella species by sequencing of the amplicons. The legionella-specific PCR assay that is described demonstrates high sensitivity and high specificity for routine detection of legionellae in respiratory samples.

Base Sequence↗
PubMed2006

The use and misuse of biomarkers in ecotoxicology.

Substantial efforts have been devoted to developing and applying biomarkers for use in ecotoxicology. These efforts have resulted partly from a desire for early warning indicators that respond before measurable effects on individuals and populations occur and partly as an aid to identifying the causes of observed population- and community-level effects. Whereas older biomarkers focused on measures of organism physiology or biochemistry, advances in molecular biology are extending the biomarker philosophy to the level of the genes (i.e., ecotoxicogenomics). However, the extent to which biomarkers are able to provide unambiguous and ecologically relevant indicators of exposure to or effects of toxicants remains highly controversial. In the present paper, we briefly discuss the application of biomarkers in ecotoxicology and ecological risk assessment, and we provide examples of how they have been applied. We conclude that although biomarkers can be helpful for gaining insight regarding the mechanisms causing observed effects of chemicals on whole-organism performance and may, in some cases, provide useful indicators of exposure, individual biomarker responses should not be expected to provide useful predictions of relevant ecological effects--and probably not even predictions of whole-organism effects. Suites of biomarkers are only likely to provide increased predictability if they can be used in a comprehensive mechanistic model that integrates them into a measure of fitness. Until this can be achieved, biomarkers may be useful for hypothesis generation in carefully controlled experiments. However, because the aims of environmental monitoring and ecological risk assessment are to detect and/or predict adverse chemical impacts on populations, communities, and ecosystems, we should be focusing our efforts on improving methods to do this directly. This will involve developing and testing models of appropriate complexity that can describe real-world systems at multiple scales.

Animals↗
PubMed2006

On the limits of toxicant-induced tolerance testing: cotolerance and response variation of antibiotic effects.

Pollution-induced community tolerance (PICT) as an ecotoxicological test system has been claimed to detect pollutant effects highly specifically and sensitively. However, the specificity might be limited by the occurrence of cotolerance. Another limitation of the application of any ecotoxicological test system lies in variation of the measured responses. We tested the variation and the occurrence of cotolerance experimentally, using antibiotics as toxicants, soil microcosms as microbial communities, and tolerance determination in Biolog plates as PICT detection test. Bacteria have been discussed as being prone to multiple tolerances due to the possible accumulation of multiple resistance genes on mobile genetic elements. However, in our experiments, cotolerance occurred only between antibiotics of the same group (oxytetracycline and tetracycline), as expected from their identical mode of action. Cotolerance between oxytetracycline and tylosin in soil microcosms exposed to oxytetracycline was low, as was cotolerance to oxytetracycline in tylosin-exposed microcosms. We conclude that tolerance development to antibiotics in soils reflects the actual selection pressure rather than a general pattern of multiple resistances. Concerning variation, the PICT effect of tetracycline was well reproducible in two consecutive years. The response variation linked to PICT experiments in controlled microcosms was comparable to that of ecotoxicological test systems of equivalent complexity. In conclusion, our results support an application of the PICT methodology as an effective means to study the soil ecotoxicology of antibiotics.

Adsorption↗
PubMed1989

Occult breast cancer in two community hospitals in New York State.

The histopathologic results of 360 consecutive preoperative needle localizations of nonpalpable breast lesions performed at two community hospitals in New York State were analyzed for comparison with national data. Seventy-eight (21.6%) samples were malignant lesions. Sixty of the 78 (76.4%) were infiltrative lesions, and 18 (23.6%) were in situ carcinomas. Overall, axillary lymph node metastases were noted in five (8.3%) samples. We conclude that needle localization permits detection of occult carcinoma at an early stage and that detection of occult carcinoma in patients seen in a community hospital corresponds well with published national data.

Breast Neoplasms↗
PubMed1996

The Cambridge Language and Speech Project (CLASP). I . Detection of language difficulties at 36 to 39 months.

A community-based investigation of the nature, characteristics and evolution of speech and language delay in a sample of 3-year-olds is being carried out in Cambridgeshire. 1936 parents completed a preschool language checklist (PLC) to identify children at risk of language difficulties. Two hundred and seventy-seven children at risk together with 148 controls completed a series of preliminary face-to-face standard language tests to determine expressive, receptive and phonological skills. Concordance between the Cambridge Language and Speech Project (CLASP) identification and speech therapy involvement suggests that the overall (CLASP) screening procedure identified a number of children that current surveillance had missed and support the conclusion that the PLC may be a useful adjunct for child health care services as an aid in prioritising children for referral to speech therapy services. Children with scores of 1 to 3 at 36 months should be reviewed at 39 months, and those with 4 or more should be a high priority for referral. Preliminary examination of the impairment profile suggests that children with language impairments rather than pure speech impairments at 36 and 39 months are more likely to have a broader range of overall language-related deficit.

Age Factors↗
PubMed2005

Geoparasites in rural Dakahlia Governorate, a preliminary based study for development of the community-based intervention programs.

A prospective study was carried out to detect the rural prevalence and intensity of geoparasites in Dakahlia Governorate, Egypt. A total of 1070 soil samples were collected; 571 (53.4%) were infected with one or more parasites. Only 24% of samples were infected with one parasite, 16.4% and 13% with two, and more than two parasites respectively, and the difference was statistically significant. The geoparasites in a descending order of their prevalence were: E. histolytica cysts (9.2%), Toxocara eggs (9.1%), Giardia cysts (7.9%), Cryptosporidium oocysts (6.1%), Trichostrongylus eggs and larvae (5.6%), Isospora oocysts (4.3%), Acanathamoeba cysts (4.1%), Naegleria cysts (3.6%), Dust mites (2.7%), H. diminuta eggs (2.7%), Strongyloides free living adults, rhabditiform and filariform larvae (2.3%), H. nana eggs (1.7%), S. mansoni eggs (1.2%), Ascaris eggs (0.6%), Ancylostoma larvae (0.5%), Taenia eggs (0.4%), Trichocephalus eggs (0.4%) and F. gigantica eggs (0.2%). The prevalence of parasitic infections was significantly higher (P<0.001) in fields (63.4%) than streets (47.7%) and indoor-yards samples (35.3%). The intensity of infections was significantly higher (P< 0.001) in streets than fields and indoor-yards (18.1, 9.7 & 1 parasite/10 gm of soil respectively).

Animals↗
PubMed2006

An introduction to thiol redox proteins in the endoplasmic reticulum and a review of current electrochemical methods of detection of thiols.

This aim of this paper is to expound the complexity of thiol redox systems in the endoplasmic reticulum of eukaryotic cells to the electroanalytical community. A summary of the state of the art in electrochemical methods for detection of thiols gives an insight into the challenges that need to be addressed to bridge the disparity between current analytical techniques and applications in a 'real' biological scenario.

Animals↗
PubMed2005

Denaturing gradient gel electrophoresis gel expansion (DGGEGE)--an attempt to resolve the limitations of co-migration in the DGGE of complex polymicrobial communities.

Recent molecular approaches for the study of microbial communities such as PCR-cloning have enabled the detection and identification of as-yet-unculturable taxa. Cloning and sequencing of multiple samples is extremely laborious and expensive to perform thoroughly due to the large diversity involved. For this purpose, techniques such as denaturing gradient gel electrophoresis (DGGE) may be better suited. There is increasing evidence suggesting that DGGE of complex polymicrobial communities may be limited by co-migration of different sequences. In this study, we attempt to address this limitation by excising individual bands and running them through a shorter denaturant gradient, a process we have termed "denaturing gradient gel electrophoresis gel expansion" (DGGEGE).

Bacteria↗
PubMedDate not supplied

Prenatal diagnosis of the 22q11.2 deletion syndrome.

The development of fluorescence in situ hybridization (FISH)- and polymerase chain reaction (PCR)-based assays for the detection of deletions of chromosome 22q11.2 has enabled the medical community to offer couples at risk prenatal diagnostic testing. Current indications for testing include a previous child with a 22q11.2 deletion or DiGeorge/velocardiofacial syndrome, an affected parent with a 22q11.2 deletion, and in utero detection of a conotruncal cardiac defect. Antenatal knowledge of the deletion status provides couples and clinicians with an accurate diagnosis, prognostic information, and recurrence risk, which may assist couples with their reproductive decisions. However, there are limitations to prenatal testing, which should be reviewed prior to testing.

Abnormalities, Multiple↗
PubMed2004

National disease burden of respiratory viruses detected in children by polymerase chain reaction.

BACKGROUND: The epidemiology of community-acquired respiratory viruses at the Children's Hospital of Wisconsin between 1996 and 1998 was examined with molecular [multiplex (M) PCR] and standard virologic methods. METHODS AND RESULTS: A total of 3325 patients with lower respiratory infection (LRI) [bronchiolitis (42%), pneumonia (38%) and croup (12%)] were identified. It is estimated that 545,000 LRI hospitalizations occur each year in the United States in children younger than 18 years old (viral, 428,000; pneumonia, 221,000; bronchiolitis, 222,000; croup, 65,000), including a continued increase in bronchiolitis hospitalizations (47.8/1000; <1 year). The most common viruses detected each year in hospitalized children included respiratory syncytial virus (A and B; 117,000), parainfluenza virus (PIV-1 and -2, 48 000; PIV-3, 18,000) and influenza (A and B, 39,000). With multiplex reverse transcription polymerase chain reaction (MPCR), different patient populations demonstrated different LRI epidemiology in relation to specific syndromes and viral causes. At least 21% of LRI hospitalizations were in children with significant medical problems.PIVs were detected much more frequently in immunocompromised children than in previously healthy children (33% vs. 16%). Similarly 15% of respiratory syncytial virus was detected between May and October, mostly in immunocompromised children. Influenza caused 19% of bronchiolitis in previously healthy children, and no virus could be reliably predicted based on clinical presentation, including wheezing. Of children hospitalized for LRI, 40% tested positive for the seven most common respiratory viruses by MPCR. CONCLUSIONS: Work is under way to expand the number of viruses detected by MPCR and to determine whether newly discovered viruses, such as human metapneumovirus, contribute to the burden of pediatric LRI hospitalizations.

Adolescent↗
PubMed2004

Spatial distribution of bacterial communities and phenanthrene degradation in the rhizosphere of Lolium perenne L.

Rhizodegradation of organic pollutants, such as polycyclic aromatic hydrocarbons, is based on the effect of root-produced compounds, known as exudates. These exudates constitute an important and constant carbon source that selects microbial populations in the plant rhizosphere, modifying global as well as specific microbial activities. We conducted an experiment in two-compartment devices to show the selection of bacterial communities by root exudates and phenanthrene as a function of distance to roots. Using direct DNA extraction, PCR amplification, and thermal gradient gel electrophoresis screening, bacterial population profiles were analyzed in parallel to bacterial counts and quantification of phenanthrene biodegradation in three layers (0 to 3, 3 to 6, and 6 to 9 mm from root mat) of unplanted-polluted (phenanthrene), planted-polluted, and planted-unpolluted treatments. Bacterial community differed as a function of the distance to roots, in both the presence and the absence of phenanthrene. In the planted and polluted treatment, biodegradation rates showed a strong gradient with higher values near the roots. In the nonplanted treatment, bacterial communities were comparable in the three layers and phenanthrene biodegradation was high. Surprisingly, no biodegradation was detected in the section of planted polluted treatment farthest from the roots, where the bacterial community structure was similar to those of the nonplanted treatment. We conclude that root exudates and phenanthrene induce modifications of bacterial communities in polluted environments and spatially modify the activity of degrading bacteria.

Bacteria↗