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1.
Fr J Urol ; 34(1): 102547, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37858376

RESUMO

BACKGROUND: MRI-guided biopsy (MGB) contributes to the diagnosis of clinically significant Prostate Cancer (csPCa). However, there are no clear recommendations for the management of men after a negative MGB. The aim of this study was to assess the risk of csPCa after a first negative MGB. METHODS: Between 2014 and 2020, we selected men with a PI-RADS score ≥ 3 on MRI and a negative MGB (showing benign findings) performed for suspected prostate cancer. MGB (targeted and systematic biopsies) was performed using fully integrated mobile fusion imaging (KOELIS). The primary endpoint was the rate of csPCa (defined as an ISUP grade ≥ 2) diagnosed after a first negative MGB. RESULTS: A total of 381 men with a negative MGB and a median age of 65 (IQR: 59-69, range: 46-85) years were included. During the median follow-up of 31 months, 124 men (32.5%) had a new MRI, and 76 (19.9%) were referred for a new MGB, which revealed csPCa in 16 (4.2%) of them. We found no statistical difference in the characteristics of men diagnosed with csPCa compared with men with no csPCa after the second MGB. CONCLUSION: We observed a risk of significant prostate cancer in 4% of men two years after a negative MRI-guided biopsy. Performing a repeat MRI could improve the selection of men who will benefit from a repeat MRI-guided biopsy, but a clear protocol is needed to follow these patients.


Assuntos
Imagem por Ressonância Magnética Intervencionista , Neoplasias da Próstata , Masculino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Biópsia Guiada por Imagem/efeitos adversos , Ultrassonografia de Intervenção/métodos , Imagem por Ressonância Magnética Intervencionista/métodos
2.
Appl Environ Microbiol ; 81(19): 6773-89, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26209667

RESUMO

The first outbreaks of bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae biovar 3 were detected in France in 2010. P. syringae pv. actinidiae causes leaf spots, dieback, and canker that sometimes lead to the death of the vine. P. syringae pv. actinidifoliorum, which is pathogenic on kiwi as well, causes only leaf spots. In order to conduct an epidemiological study to track the spread of the epidemics of these two pathogens in France, we developed a multilocus variable-number tandem-repeat (VNTR) analysis (MLVA). MLVA was conducted on 340 strains of P. syringae pv. actinidiae biovar 3 isolated in Chile, China, France, Italy, and New Zealand and on 39 strains of P. syringae pv. actinidifoliorum isolated in Australia, France, and New Zealand. Eleven polymorphic VNTR loci were identified in the genomes of P. syringae pv. actinidiae biovar 3 ICMP 18744 and of P. syringae pv. actinidifoliorum ICMP 18807. MLVA enabled the structuring of P. syringae pv. actinidiae biovar 3 and P. syringae pv. actinidifoliorum strains in 55 and 16 haplotypes, respectively. MLVA and discriminant analysis of principal components revealed that strains isolated in Chile, China, and New Zealand are genetically distinct from P. syringae pv. actinidiae strains isolated in France and in Italy, which appear to be closely related at the genetic level. In contrast, no structuring was observed for P. syringae pv. actinidifoliorum. We developed an MLVA scheme to explore the diversity within P. syringae pv. actinidiae biovar 3 and to trace the dispersal routes of epidemic P. syringae pv. actinidiae biovar 3 in Europe. We suggest using this MLVA scheme to trace the dispersal routes of P. syringae pv. actinidiae at a global level.


Assuntos
Actinidia/microbiologia , Repetições Minissatélites , Doenças das Plantas/microbiologia , Pseudomonas syringae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Surtos de Doenças , França/epidemiologia , Frutas/microbiologia , Variação Genética , Dados de Sequência Molecular , Filogenia , Doenças das Plantas/estatística & dados numéricos , Pseudomonas syringae/classificação , Pseudomonas syringae/genética
3.
J Microbiol Methods ; 92(1): 42-50, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23142341

RESUMO

In this study we developed an algorithm to screen for all exact molecular signatures of the quarantine pathogen Xanthomonas axonopodis pv. phaseoli (Xap), based on available data of the presence or absence of virulence-associated genes. The simultaneous presence of genes avrBsT and xopL is specific to Xap. Therefore we developed a multiplex PCR assay targeting avrBsT and xopL for the molecular identification of Xap. The specificity of this multiplex was validated by comparison to that of other molecular identification assays aimed at Xap, on a wide collection of reference strains. This multiplex was further validated on a blind collection of Xanthomonas isolates for which pathogenicity was assayed by stem wounding and by dipping leaves into calibrated inocula. This multiplex was combined to the previously described X4c/X4e molecular identification assay for Xap. Such a combination enables the molecular identification of all strains of Xanthomonas pathogenic on bean. Results also show that assay by stem wounding does not give reliable results in the case of Xap, and that pathogenicity assays by dipping should be preferred.


Assuntos
Técnicas Bacteriológicas/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Fatores de Virulência/genética , Xanthomonas axonopodis/isolamento & purificação , Doenças das Plantas/microbiologia , Plantas/microbiologia , Quarentena , Xanthomonas axonopodis/genética
4.
Appl Environ Microbiol ; 78(9): 3266-79, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22389364

RESUMO

Pseudomonas syringae pv. maculicola causes bacterial spot on Brassicaceae worldwide, and for the last 10 years severe outbreaks have been reported in the Loire Valley, France. P. syringae pv. maculicola resembles P. syringae pv. tomato in that it is also pathogenic for tomato and causes the same types of symptoms. We used a collection of 106 strains of P. syringae to characterize the relationships between P. syringae pv. maculicola and related pathovars, paying special attention to P. syringae pv. tomato. Phylogenetic analysis of gyrB and rpoD gene sequences showed that P. syringae pv. maculicola, which causes diseases in Brassicaceae, forms six genetic lineages within genomospecies 3 of P. syringae strains as defined by L. Gardan et al. (Int. J. Syst. Bacteriol. 49[Pt 2]:469-478, 1999), whereas P. syringae pv. tomato forms two distinct genetic lineages. A multilocus variable-number tandem-repeat (VNTR) analysis (MLVA) conducted with eight minisatellite loci confirmed the genetic structure obtained with rpoD and gyrB sequence analyses. These results provide promising tools for fine-scale epidemiological studies on diseases caused by P. syringae pv. maculicola and P. syringae pv. tomato. The two pathovars had distinct host ranges; only P. syringae pv. maculicola strains were pathogenic for Brassicaceae. A subpopulation of P. syringae pv. maculicola strains that are pathogenic for Pto-expressing tomato plants were shown to lack avrPto1 and avrPtoB or to contain a disrupted avrPtoB homolog. Taking phylogenetic and pathological features into account, our data suggest that the DC3000 strain belongs to P. syringae pv. maculicola. This study shows that P. syringae pv. maculicola and P. syringae pv. tomato appear multiclonal, as they did not diverge from a single common ancestral group within the ancestral P. syringae genomospecies 3, and suggests that pathovar specificity within P. syringae may be due to independent genetic events.


Assuntos
DNA Bacteriano/genética , Genes Essenciais , Especificidade de Hospedeiro , Pseudomonas syringae/genética , Brassicaceae/microbiologia , DNA Girase/genética , DNA Bacteriano/química , RNA Polimerases Dirigidas por DNA/genética , França , Solanum lycopersicum/microbiologia , Repetições de Microssatélites , Repetições Minissatélites , Dados de Sequência Molecular , Tipagem Molecular , Doenças das Plantas/microbiologia , Pseudomonas syringae/classificação , Análise de Sequência de DNA
5.
Syst Appl Microbiol ; 34(2): 156-65, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21193279

RESUMO

Previous classification of Xanthomonas campestris has defined six pathovars (aberrans, armoraciae, barbareae, campestris, incanae, and raphani) that cause diseases on cruciferous plants. However, pathogenicity assays with a range of strains and different hosts identifies only three types of symptom: black rot, leaf spot and bacterial blight. These findings raise the question of the genetic relatedness between strains assigned to different pathovars or symptom phenotypes. Here we have addressed this issue by multilocus sequence analysis of 42 strains. The X. campestris species was polymorphic at the 8 loci analysed and had a high genetic diversity; 23 sequence types were identified of which 16 were unique. All strains that induce black rot (pathovars aberrans and campestris) were genetically close but split in two groups. Only three clonal complexes were found, all within pathovar campestris. The assignment of the genome-sequenced strain 756C to pathovar raphani suggested from disease symptoms was confirmed, although this group of strains was particularly polymorphic. Strains belonging to pathovars barbareae and incanae were closely related, but distinct from pathovar campestris. There is evidence of genetic exchanges of housekeeping genes within this species as deduced from a clear incongruence between individual gene phylogenies and from network structures from SplitsTree analysis. Overall this study showed that the high genetic diversity derived equally from recombination and point mutation accumulation. However, X. campestris remains a species with a clonal evolution driven by a differential adaptation to cruciferous hosts.


Assuntos
Brassicaceae/microbiologia , Xanthomonas campestris/genética , Técnicas de Tipagem Bacteriana , Ligação Genética , Variação Genética , Tipagem de Sequências Multilocus , Filogenia , Recombinação Genética , Xanthomonas campestris/classificação
6.
Rev Laryngol Otol Rhinol (Bord) ; 131(4-5): 235-41, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21866733

RESUMO

OBJECTIVE: What is the status of postural control a few months after an attack of vestibular neuritis (VN)? Using dynamic posturography and stabilometric signal treatment with wavelets and fractal analysis, we tried to answer this question by isolating the pathological postural parameters of VN. MATERIAL AND METHOD: The study involved a group of 15 patients (GP) who suffered from VN and were compared to a group of control subjects (GC). Both groups underwent videonystagmography (VNG), dynamic posturography (PDY), and assessment using symptomatic scales (ES). RESULTS: GP and GC were comparable in terms of age mean, sex-ratio, average height and weight. The differences between GP and GC were the following videonystagmography criteria: Spontaneous nystagmus (NS) (P= 0.005), head shaking test (HST) (p= 0.001), vibratory test (TVO) (p= 0.009). There were also differences in the symptomatic scales scores for the vertigo symptom scale (VSS) (p= 0.011), the dizziness handicap inventory (DHI) (p= 0.001), and the short form 36 (SF36) (p= 0.01). All the 84 new parameters of both GP and GC differ. This difference was significant (p< 0.05) in 16 cases (19%), and highly significant (p< 0.01) in 11 other cases (13%). The condition ("unsteady platforms" was the greatest determinant in both groups while the (closed eyess and (HST> conditions were found to be non-discriminating. CONCLUSION: Vestibular neuritis affects new stabilometric parameters. These parameters are more adapted to the present setup compared to previous parameters which are used to analyse non-periodic oscillations of posture. They are important in follow-up and rehabilitation of patients.


Assuntos
Fractais , Equilíbrio Postural/fisiologia , Neuronite Vestibular/fisiopatologia , Análise de Ondaletas , Adulto , Idoso , Estudos de Casos e Controles , Eletronistagmografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Appl Environ Microbiol ; 74(9): 2669-78, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18326683

RESUMO

Understanding the survival, multiplication, and transmission to seeds of plant pathogenic bacteria is central to study their pathogenesis. We hypothesized that the type III secretion system (T3SS), encoded by hrp genes, could have a role in host colonization by plant pathogenic bacteria. The seed-borne pathogen Xanthomonas fuscans subsp. fuscans causes common bacterial blight of bean (Phaseolus vulgaris). Directed mutagenesis in strain CFBP4834-R of X. fuscans subsp. fuscans and bacterial population density monitoring on bean leaves showed that strains with mutations in the hrp regulatory genes, hrpG and hrpX, were impaired in their phyllospheric growth, as in the null interaction with Escherichia coli C600 and bean. In the compatible interaction, CFBP4834-R reached high phyllospheric population densities and was transmitted to seeds at high frequencies with high densities. Strains with mutations in structural hrp genes maintained the same constant epiphytic population densities (1 x 10(5) CFU g(-1) of fresh weight) as in the incompatible interaction with Xanthomonas campestris pv. campestris ATCC 33913 and the bean. Low frequencies of transmission to seeds and low bacterial concentrations were recorded for CFBP4834-R hrp mutants and for ATCC 33913, whereas E. coli C600 was not transmitted. Moreover, unlike the wild-type strain, strains with mutations in hrp genes were not transmitted to seeds by vascular pathway. Transmission to seeds by floral structures remained possible for both. This study revealed the involvement of the X. fuscans subsp. fuscans T3SS in phyllospheric multiplication and systemic colonization of bean, leading to transmission to seeds. Our findings suggest a major contribution of hrp regulatory genes in host colonization processes.


Assuntos
Proteínas de Transporte/metabolismo , Fabaceae/microbiologia , Doenças das Plantas/microbiologia , Sementes/microbiologia , Xanthomonas/fisiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Capsicum/microbiologia , Proteínas de Transporte/genética , Contagem de Colônia Microbiana , DNA Bacteriano/química , DNA Bacteriano/genética , Escherichia coli/crescimento & desenvolvimento , Deleção de Genes , Ordem dos Genes , Dados de Sequência Molecular , Família Multigênica , Mutagênese Insercional , Phaseolus/microbiologia , Transporte Proteico , Análise de Sequência de DNA , Xanthomonas/genética , Xanthomonas/crescimento & desenvolvimento
8.
Appl Environ Microbiol ; 71(12): 8292-300, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16332815

RESUMO

The spatial distribution of vine plants contaminated by Xylophilus ampelinus, the agent responsible for bacterial necrosis, was studied over a 5-year period within two vineyards in the Cognac area. Both vineyards were planted with Vitis vinifera cv. Ugni blanc but were different in age and agronomic location. The emission of X. ampelinus in contaminated bleeding sap was observed during vine sprouting. Contaminated bleeding sap is an important source of inoculum for external contamination due to the high susceptibility of young merging shoots to the pathogen. X. ampelinus emission by bleeding sap was not affected by the age of the plants or the location of the vineyards. However, its emission was irregular with time, and it varied between two fruit canes from individual plants and between plants as well as between years. Moreover, the two vineyards appeared to be entirely contaminated. Consequently, the behavior of the pathogen is not predictable. The distribution of the pathogen inside vine plant organs was analyzed through the four growing seasons. The old wood was contaminated throughout the year and constituted a stock inoculum for endophytic contamination of crude sap during the winter and the spring. Despite the fact that most of the young green shoots were contaminated in May, X.ampelinus was not found in green shoots in June and September, refuting the hypothesis of an epiphytic life of the pathogen under natural conditions. Although all plants were entirely contaminated in both vineyards, symptoms were rare and were observed on different plants each year.


Assuntos
Burkholderiaceae/patogenicidade , Vitis/microbiologia , Vinho/microbiologia , Burkholderiaceae/genética , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Contaminação de Alimentos , França , Geografia , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase , Madeira
9.
Int J Syst Evol Microbiol ; 54(Pt 1): 15-24, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14742454

RESUMO

Bacterial blight is an emerging disease that affects primarily onion, but also garlic and Welsh onion. The present study was undertaken to characterize the causative xanthomonad(s) by a polyphasic approach using a worldwide collection of 33 bacterial strains. Analysis of 16S rRNA gene sequence similarities indicated that the causal agent belongs to the campestris core in the genus Xanthomonas, which is in agreement with results of phenotypic characterization (analyses of carbon source utilization and fatty acid methyl esters). However, DNA-DNA hybridization, thermal stability of DNA reassociation and fluorescent amplified fragment length polymorphism analysis allowed the causal agent to be identified as a pathovar of Xanthomonas axonopodis.


Assuntos
Allium/microbiologia , Alho/microbiologia , Cebolas/microbiologia , Xanthomonas/classificação , Primers do DNA , Dados de Sequência Molecular , Filogenia , Doenças das Plantas/microbiologia , RNA Ribossômico 16S/genética , Xanthomonas/genética , Xanthomonas/isolamento & purificação , Xanthomonas/patogenicidade
10.
Appl Environ Microbiol ; 67(8): 3379-84, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11472907

RESUMO

The randomly amplified polymorphic DNA (RAPD) method was used to investigate the genetic diversity in Xanthomonas cynarae, which causes bacterial bract spot disease of artichoke. This RAPD analysis was also intended to identify molecular markers characteristic of this species, in order to develop PCR-based markers which can be used to detect this pathogenic bacterium in artichoke fields. Among the 340 RAPD primers tested, 40 were selected on their ability to produce reproducible and reliable fingerprints in our genetic background. These 40 primers produced almost similar patterns for the 37 X. cynarae strains studied, different from the fingerprints obtained for other Xanthomonas species and other xanthomonad-like bacteria isolated from artichoke leaves. Therefore, X. cynarae strains form a homogeneous genetic group. However, a little DNA polymorphism within this species was observed and the collection of X. cynarae isolates was divided into two groups (one containing three strains, the second one including all other strains). Out of seven RAPD markers characteristic of X. cynarae that were cloned, four did not hybridize to the genomic DNA of strains belonging to other Xanthomonas species. These four RAPD markers were converted into PCR markers (specific characterized amplified regions [SCARs]); they were sequenced, and a PCR primer pair was designed for each of them. Three derived SCARs are good candidates to develop PCR-based tests to detect X. cynarae in artichoke fields.


Assuntos
Asteraceae/microbiologia , Variação Genética , Doenças das Plantas/microbiologia , Técnica de Amplificação ao Acaso de DNA Polimórfico , Xanthomonas/genética , Primers do DNA , Marcadores Genéticos , Reação em Cadeia da Polimerase , Especificidade da Espécie , Xanthomonas/classificação
11.
Int J Syst Evol Microbiol ; 50 Pt 4: 1471-1478, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10939652

RESUMO

A bacterial disease of artichoke (Cynara scolymus L.) was first observed in 1954 in Brittany and the Loire Valley, France. This disease causes water-soaked spots on bracts and depreciates marketability of the harvest. Ten strains of the pathogen causing bacterial spot of artichoke, previously identified as a member of the genus Xanthomonas, were characterized and compared with type and pathotype strains of the 20 Xanthomonas species using a polyphasic study including both phenotypic and genomic methods. The ten strains presented general morphological, biochemical and physiological traits and G+C content characteristic of the genus Xanthomonas. Sequencing of the 165 rRNA gene confirmed that this bacterium belongs to the genus Xanthomonas, and more precisely to the Xanthomonas campestris core. DNA-DNA hybridization results showed that the strains that cause bacterial spot of artichoke were 92-100% related to the proposed type strain CFBP 4188T and constituted a discrete DNA homology group that was distinct from the 20 previously described Xanthomonas species. The results of numerical analysis were in accordance with DNA-DNA hybridization data. Strains causing the bacterial bract spot of artichoke exhibited consistent determinative biochemical characteristics, which distinguished them from the 20 other Xanthomonas species previously described. Furthermore, pathogenicity tests allowed specific identification of this new phytopathogenic bacterium. Thus, it is concluded that this bacterium is a new species belonging to the genus Xanthomonas, for which the name Xanthomonas cynarae is proposed. The type strain, CFBP 4188T, has been deposited in the Collection Française des Bactéries Phytopathogènes (CFBP).


Assuntos
Genes Bacterianos , Plantas/microbiologia , Xanthomonas/genética , Composição de Bases , Clonagem Molecular , DNA Bacteriano , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fenótipo , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Xanthomonas/química , Xanthomonas/classificação
12.
J Laparoendosc Adv Surg Tech A ; 10(3): 155-9, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10883993

RESUMO

BACKGROUND AND PURPOSE: Postoperative adhesions are the leading cause of small-bowel obstruction in developed countries. Several arguments suggest that laparoscopy may lead to fewer adhesions than does laparotomy. We report here the short-term results of laparoscopy in patients admitted on an emergency basis for acute small-bowel obstruction secondary to adhesions. PATIENTS AND METHODS: This prospective trial included 134 consecutive patients: 39 underwent emergency surgery, and 95 had laparoscopic adhesiolysis shortly after resolution of the obstruction with nasogastric suction. Of the previous operations for which the dates were known, 16% had taken place within 1 year of the obstruction and 33.5% within 5 years. In all, 27% of the patients had open laparoscopy, and 16% had conversions: 7% after elective laparoscopy and 36% after emergency laparoscopy. RESULTS: There were no operative deaths. One patient underwent a reoperation the following day for fistula after incomplete adhesiolysis attributable to multiple adhesions found during elective laparoscopy. If laparoscopy is considered to have failed when adhesiolysis was incomplete or conversion or reoperation was necessary, our success rate was 80% after elective laparoscopy and 59% after emergency laparoscopy. CONCLUSION: Emergency situations in acute small-bowel obstruction combine several circumstances unfavorable for laparoscopy: a limited work area and a distended and fragile small bowel. Laparoscopic adhesiolysis after the crisis has passed may produce better results, but only long-term follow-up can confirm the role of elective laparoscopy for this indication.


Assuntos
Obstrução Intestinal/cirurgia , Laparoscopia , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Emergências , Feminino , Humanos , Obstrução Intestinal/etiologia , Intestino Delgado , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/cirurgia , Estudos Prospectivos , Aderências Teciduais/complicações , Resultado do Tratamento
13.
Ann Chir ; 53(9): 859-64, 1999.
Artigo em Francês | MEDLINE | ID: mdl-10633932

RESUMO

Postoperative adhesions are the first cause of small bowel occlusion in developed countries. Nevertheless no progress was done in prevention and treatment of this disease. The aim of this trial is to report results of 276 small bowel occlusions caused by adhesion recently operated and consecutive between first january 1993 and 31 december 1996. These patients had 400 previous surgical procedures, within 67.4% infra mesocolic or pelvic. 15.1% of previous surgical procedures took place less than one year before and 36% less than 5 years. Thirty five per cent of patients were operated during 24 hours following admission 23.2% of patients had a digestive resection, caused by necrosis or iatrogenic dissection. Operative mortality was 4.3% without resection and 16.6% with resection. Progress are warranted to reduce the rate of redux of occlusion and mortality and morbidity in this benign disease: more peri operative attention and place of laparoscopy should be considered.


Assuntos
Obstrução Intestinal/etiologia , Intestino Delgado , Complicações Pós-Operatórias , Procedimentos Cirúrgicos Operatórios/efeitos adversos , Aderências Teciduais/complicações , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Emergências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação , Fatores de Tempo
14.
Appl Environ Microbiol ; 64(4): 1180-7, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16349533

RESUMO

Recently, DNA pairing analyses showed that Pseudomonas syringae pv. tomato and related pathovars, including P. syringae pv. maculicola, form a genomic species (Pseudomonas tomato) (L. Gardan, H. L. Shafik, and P. A. D. Grimont, p. 445-448, in K. Rudolph, T. J. Burr, J. W. Mansfield, D. Stead, A. Vivian, and J. von Kietzell, ed., Pseudomonas syringae Pathovars and Related Pathogens, 1997). The genetic diversity of 23 strains belonging to this genomic species and 4 outgroup strains was analyzed with randomly amplified polymorphic DNA (RAPD) and amplified fragment length polymorphic (AFLP) techniques. Simple boiling of P. syringae cells was suitable for subsequent DNA amplification to obtain reliable patterns in RAPD and AFLP analyses. In general, the grouping of P. syringae strains by both analysis techniques corresponded well with the classification obtained from an RFLP analysis of ribosomal DNA operons, DNA pairing studies, and an analysis of pathogenicity data. However, two strains of P. syringae pv. maculicola produced distinct DNA patterns compared to the DNA patterns of other P. syringae pv. maculicola strains; these patterns led us to assume that horizontal transfer of DNA could occur between bacterial populations. Both techniques used in this study have high discriminating power because strains of P. syringae pv. tomato and P. syringae pv. maculicola which were indistinguishable by other techniques, including pathogenicity tests on tomato, were separated into two groups by both RAPD and AFLP analyses. In addition, data analysis showed that the AFLP method was more efficient for assessing intrapathovar diversity than RAPD analysis and allowed clear delineation between intraspecific and interspecific genetic distances, suggesting that it could be an alternative to DNA pairing studies. However, it was not possible to distinguish the two races of P. syringae pv. tomato on the basis of an analysis of the data provided by either the AFLP or RAPD technique.

15.
Appl Environ Microbiol ; 63(2): 498-505, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9023928

RESUMO

Phylogenetic relationships among 77 bacterial strains belonging to Pseudomonas syringae and Pseudomonas viridiflava species were assessed by analysis of the PCR-restriction fragment length polymorphism (RFLP) patterns of three DNA fragments corresponding to rrs and rrl genes and the internal transcribed spacer, ITS1. No difference among all strains in rrs and rrl genes was observed with 14 restriction enzymes, which confirms the close relationships existing between these two species. The nucleotidic sequence of the internal transcripted spacer (ITS1) between rrs and rrl for the P. syringae pv. syringae strain CFBP1392 was determined. Restriction maps of the PCR-amplified ITS1 region were prepared and compared for all 77 strains. Seventeen RFLP patterns, forming three main clusters, were distinguished. One contained all strains of P. syringae pv. tomato and of other pathovars which had been previously described as closely related by either pathogenicity studies or biochemical analyses. This cluster was equally far from P. viridiflava and from other P. syringae pathovars. These other pathovars of P. syringae formed a less coherent taxon.


Assuntos
DNA Ribossômico/genética , Variação Genética , Polimorfismo de Fragmento de Restrição , Pseudomonas/classificação , Pseudomonas/genética , Solanum lycopersicum/microbiologia , Dados de Sequência Molecular , Óperon/genética , Filogenia , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase , Pseudomonas/patogenicidade , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Mapeamento por Restrição , Análise de Sequência de DNA
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