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1.
Org Biomol Chem ; 16(23): 4231-4235, 2018 06 13.
Article in English | MEDLINE | ID: mdl-29796555

ABSTRACT

A new preparation of δ-lactams is reported. In the presence of a Lewis acid promoter, alkoxyisocoumarins engage a range of N-aryl and N-alkyl imines to form δ-lactams with a pendent carboalkoxy substituent. A sulfonamide-thiourea catalyst enables the synthesis of these products in moderate to good enantioselectivities.


Subject(s)
Imines/chemistry , Isocoumarins/chemistry , Lactams/chemical synthesis , Catalysis , Cyclization , Cycloaddition Reaction , Lactams/chemistry , Stereoisomerism , Sulfonamides/chemistry , Thiourea/analogs & derivatives
2.
An Pediatr (Barc) ; 80(6): 399-403, 2014 Jun.
Article in Spanish | MEDLINE | ID: mdl-24286883

ABSTRACT

INTRODUCTION: Varicella (chickenpox) can cause serious complications and admission to hospital. Several countries included the varicella vaccine in their immunization schedules. MATERIAL AND METHODS: A descriptive and retrospective study of hospitalizations due to varicella and its complications was conducted in a referral center from 2005 to 2011. RESULTS: A total of 1192 children with varicella were seen in the emergency room, of which 99 (8.5%) required admission. The annual incidence of admissions due to varicella and varicella complications was, 19.4 and 15.3 cases per 100,000 children under 14 years, respectively. Complications were more common in children under 5 years (79.5%), and with no underlying disease (78.2%). Infection of skin and soft tissue was the most common complication (62%). The mean hospital stay was 4.5 days (SD 4). CONCLUSIONS: Varicella causes high morbidity, and is more frequent in absolute terms in healthy children under 5 years of age. Therefore, routine vaccination recommended by the Immunization Advisory Committee should be mandatory.


Subject(s)
Chickenpox/epidemiology , Patient Admission/statistics & numerical data , Adolescent , Chickenpox/complications , Child , Child, Preschool , Female , Humans , Infant , Male , Retrospective Studies , Tertiary Care Centers
3.
Infection ; 42(1): 179-83, 2014 Feb.
Article in English | MEDLINE | ID: mdl-23709293

ABSTRACT

The isolation of Chryseobacterium indologenes as a causative micro-organism in human diseases is rare. Risk factors for infections caused by this pathogen include very young and very old age, indwelling devices, immune suppression and recent use of broad-spectrum antibiotics. Most cases suffer from bacteraemia or nosocomial pneumonia, whilst infection of the central nervous system (CNS) is extremely rare. We present a term-born infant diagnosed prenatally with holoprosencephaly and obstructive hydrocephalus, requiring post-natal ventriculoperitoneal shunt insertion. At 6 weeks of age, he suffered from Escherichia coli meningitis, showing satisfactory clinical response with antimicrobial therapy. Aged 11 months, he suffered from hyper-drainage syndrome, resulting in the removal of the shunt system. He represented 11 days post-operatively, with low-grade fever, irritability and cerebrospinal fluid (CSF) leakage. C. indologenes from CSF was isolated and antimicrobial therapy with ceftazidime and trimethoprim-sulfamethoxazole for 3 weeks resulted in good clinical response. This is the first documented community-acquired CNS infection due to C. indologenes in an infant without concomitant indwelling device or previous antibiotic pressure.


Subject(s)
Central Nervous System Infections/diagnosis , Central Nervous System Infections/microbiology , Chryseobacterium/isolation & purification , Communicable Diseases, Emerging/diagnosis , Communicable Diseases, Emerging/microbiology , Flavobacteriaceae Infections/diagnosis , Flavobacteriaceae Infections/microbiology , Anti-Bacterial Agents/therapeutic use , Ceftazidime/therapeutic use , Central Nervous System Infections/drug therapy , Cerebrospinal Fluid/microbiology , Communicable Diseases, Emerging/drug therapy , Community-Acquired Infections/diagnosis , Community-Acquired Infections/drug therapy , Community-Acquired Infections/microbiology , Flavobacteriaceae Infections/drug therapy , Humans , Infant , Male , Treatment Outcome , Trimethoprim, Sulfamethoxazole Drug Combination/therapeutic use
4.
Pediatr Pulmonol ; 49(3): E78-81, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24136903

ABSTRACT

Churg-Strauss syndrome (CSS) is an anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis; it is extremely rare in childhood and defined according to the Chapel-Hill Consensus as an eosinophil-rich and granulomatous inflammation involving the respiratory tract and necrotizing vasculitis affecting small to medium-sized vessels. Children commonly have a history of asthma and sinusitis whilst clinical presentation typically involves pulmonary tract and less frequently skin, heart, gastrointestinal tract, and peripheral nerves. Cardiopulmonary disease is higher in children and prognosis is worse. It is associated with significant eosinophilia and raised serum IgE-levels. ANCA are only found in 25% of childhood cases. Here we report the case of a 10-year-old girl who presented to us with vomiting, abdominal pain, and weight loss, paresthesias of lower extremities and breathlessness as well as a history of asthma, sinusitis and allergic rhinitis. She was treated with corticosteroids, cyclophosphamide, intravenous immunoglobulin, mycophenolate mofetil (MMF), and rituximab. However, remission was only achieved after initiation of omalizumab therapy, a recombinant humanized anti-IgE antibody. To the best of our knowledge this is the first pediatric patient suffering from CSS successfully managed with adjuvant anti-IgE therapy resulting in the control of respiratory as well as gastrointestinal symptoms.


Subject(s)
Antibodies, Anti-Idiotypic/therapeutic use , Antibodies, Monoclonal, Humanized/therapeutic use , Churg-Strauss Syndrome/drug therapy , Immunomodulation , Lung/diagnostic imaging , Pericardial Effusion/diagnostic imaging , Skin/pathology , Child , Churg-Strauss Syndrome/complications , Churg-Strauss Syndrome/diagnosis , Female , Humans , Omalizumab , Pericardial Effusion/etiology , Radiography , Treatment Outcome , Ultrasonography
5.
J Appl Microbiol ; 108(3): 818-830, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19735328

ABSTRACT

AIMS: To assess the phenotypic, symbiotic and genotypic diversity scope of Mesorhizobium spp. strains associated with Acacia seyal (Del.) isolated from different agro-ecological zones in Senegal, and uses of susceptible microbial inoculum in a reafforestation process. METHODS AND RESULTS: A polyphasic approach including phenotypic and genotypic techniques was used to study the diversity and their relationships with other biovars and species of rhizobia. The geographical origins of the strains have limited effect on their phylogenetic and phenotypic classification. Nodulation tests indicated promiscuity of the strains studied, because they were capable of nodulating six woody legume species (Acacia auriculiformis, Acacia senegal, A. seyal, Acacia tortilis ssp. raddiana, Leucaena leucocephala and Prosopis juliflora). Sequencing and phylogenetic analyses of nodA, nodC and nifH genes pointed out that in contrast to nodA gene, the phylogenies of nodC and nifH genes were not consistent with that of 16S rRNA, indicating that these genes of the A. seyal-nodulating rhizobia might have different origins. Microbial inoculation on nonsterile soil had significant effect on the nodules number and the growth of the seedlings, indicating that these strains of rhizobia might be used as inoculum. CONCLUSIONS: The results indicated that A. seyal is a nonselective host that can establish effective symbiosis with Mesorhizobium spp. strains from diverse genomic backgrounds and that the selected A. seyal-nodulating rhizobia could enhance plant growth. SIGNIFICANCE AND IMPACT OF THE STUDY: These results showed the important role that A. seyal could play in the improvement of reafforestation process as a promiscuous host, which can establish effective symbiosis with rhizobia from diverse genomic backgrounds.


Subject(s)
Acacia/microbiology , Alphaproteobacteria/genetics , Phylogeny , Soil Microbiology , Symbiosis/genetics , Alphaproteobacteria/classification , Alphaproteobacteria/isolation & purification , Genes, Bacterial , Genes, rRNA , Genotype , Phenotype , Rhizobium/classification , Rhizobium/genetics , Root Nodules, Plant/microbiology , Senegal
6.
Nefrología (Madr.) ; 28(supl.6): 127-132, ene.-dic. 2008. ilus, tab
Article in Spanish | IBECS | ID: ibc-104333

ABSTRACT

El objetivo de este trabajo es conocer el programa de formación que reciben los pacientes en Diálisis Peritoneal (DP) domiciliaria en España. Para el estudio se diseñó una encuesta con 50 preguntas cerradas y una abierta. Se envió a 104 hospitales y se obtuvo una participación del 78,84% (n = 82).La media de pacientes en DP en los centros encuestados fue de 27,6 pacientes: 15,8 en Diálisis Peritoneal Ambulatoria Continúa (DPCA) y 11,8 en Diálisis Peritoneal Automática(DPA).Con el resto de las preguntas investigamos sobre la metodología de enseñanza en las diferentes unidades, la implicación de la familia en los planes de formación, los conocimientos básicos que se daban al paciente sobre la Enfermedad Renal Crónica, las actividades necesarias para la realización del tratamiento, y la preparación que se proporciona para que puedan solucionar pequeñas eventualidades o emergencias y mejorar su calidad de vida. Se evaluó el plan de formación de los pacientes autosuficientes que estuvieran en DPA y por último, se dejó un apartado donde los diferentes centros añadieran aquello que no recogiera la encuesta. Con los resultados obtenidos pudimos concluir que en la mayoría de los centros de España existe un plan de formación en DP que puede capacitar a los pacientes o al cuidador informa la realizar el tratamiento de forma segura en su domicilio, proporcionarle los conocimientos básicos sobre la enfermedad y las actividades rutinarias para el tratamiento, poder solventar eventualidades y emergencias, así como mejorar su calidad de vida estando en diálisis (AU)


The objective of the present study is to obtain information about the training programme for patients undergoing Domiciliary Peritoneal Dialysis (DPD) in Spain. For the purposes of the study we designed a questionnaire comprising50 closed-ended items and one open response item. The questionnaire was sent to 104 hospitals and was completed by78.84% of them (n = 82).The average of patients undergoing peritoneal dialysis (PD) in the hospitals under study was 27.6: 15.8 of them receiving Chronic Ambulatory Peritoneal Dialysis (CAPD) and 11.8 Automatic Peritoneal Dialysis (APD).The questionnaire also served to investigate into the training methodology used in the different units, the involvement of the family in the programme, the basic knowledge patients received about Chronic Renal Insufficiency, the procedures associated with the therapy and the preparation they obtained to solve small-scale contingencies and emergency situations as well as the improvement of their quality of life. We also evaluated the training programme of autonomous patients on DPD and at the end of the questionnaire a blank space was left for facilities to add any comments or suggestions they considered relevant. From the results obtained we may conclude that most Spanish hospitals have devised a training planning for patients undergoing PD which helps them or caregivers to perform domiciliary treatment safely, provides them with basic knowledge about the disease and the routine procedures associated with the treatment, enables them to cope with contingencies and emergency situations and improves their quality of life during the dialysis period (AU)


Subject(s)
Humans , /methods , Renal Insufficiency, Chronic/therapy , Patient Education as Topic/methods , Caregivers/education
7.
Nefrologia ; 28 Suppl 6: 127-32, 2008.
Article in Spanish | MEDLINE | ID: mdl-18957023

ABSTRACT

The objective of the present study is to obtain information about the training programme for patients undergoing Domiciliary Peritoneal Dialysis (DPD) in Spain. For the purposes of the study we designed a questionnaire comprising 50 closed-ended items and one open response item. The questionnaire was sent to 104 hospitals and was completed by 78.84% of them (n > or = 82). The average of patients undergoing peritoneal dialysis (PD) in the hospitals under study was 27.6: 15.8 of them receiving Chronic Ambulatory Peritoneal Dialysis (CAPD) and 11.8 Automatic Peritoneal Dialysis (APD). The questionnaire also served to investigate into the training methodology used in the different units, the involvement of the family in the programme, the basic knowledge patients received about Chronic Renal Insufficiency, the procedures associated with the therapy and the preparation they obtained to solve small-scale contingencies and emergency situations as well as the improvement of their quality of life. We also evaluated the training programme of autonomous patients on DPD and at the end of the questionnaire a blank space was left for facilities to add any comments or suggestions they considered relevant. From the results obtained we may conclude that most Spanish hospitals have devised a training planning for patients undergoing PD which helps them or caregivers to perform domiciliary treatment safely, provides them with basic knowledge about the disease and the routine procedures associated with the treatment, enables them to cope with contingencies and emergency situations and improves their quality of life during the dialysis period.


Subject(s)
Patient Education as Topic , Peritoneal Dialysis , Hemodialysis, Home , Humans , Spain , Surveys and Questionnaires
8.
Lett Appl Microbiol ; 47(2): 85-97, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18565139

ABSTRACT

AIMS: We characterized phenotypically and genotypically root-nodulating bacteria associated with Acacia senegal (L.) Willd. isolated from the soils surrounding A. senegal trees in the dry land area of Senegal. METHODS AND RESULTS: The phenotypical and genotypical characterizations we carried out showed a high diversity of A. senegal root-nodulating bacteria. Phenotypic patterns showed adaptations of the rhizobial strains to many environmental stresses such as heat, drought, and salinity. Twelve molecular groups were distinguished by profiles obtained using polymerase chain reaction/restriction fragment length polymorphism techniques from intergenic spacer region rDNA. The highest genetic diversity was found around the A. senegal rhizosphere. Therefore, A. senegal seemed to have a positive influence on occurrence and genotypical diversity of rhizobial populations. Rhizobial isolates obtained in this study belonged phylogenetically to the genera Mesorhizobium and Rhizobium. CONCLUSIONS: Our results provided information about the genetic diversity of the rhizobial strains associated with A. senegal and suggested the adaptability of natural rhizobial populations to major ecological environmental stress within these soil environments. SIGNIFICANCE AND IMPACT OF THE STUDY: These results suggested a potential selection of compatible and well adapted strains under stress conditions as inoculants for successful A. senegal growth in arid lands.


Subject(s)
Acacia/microbiology , Alphaproteobacteria/classification , Alphaproteobacteria/isolation & purification , Soil Microbiology , Alphaproteobacteria/genetics , Biodiversity , Cluster Analysis , DNA Fingerprinting , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/genetics , Genes, rRNA , Genotype , Phylogeny , Plant Roots/microbiology , Polymorphism, Restriction Fragment Length , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics , Senegal , Sequence Analysis, DNA , Sequence Homology, Nucleic Acid
9.
Lett Appl Microbiol ; 45(1): 95-9, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17594467

ABSTRACT

AIMS: The aim of this study was to optimize DNA extraction from legume nodules to obtain large amounts of high-quality genomic DNA. METHODS AND RESULTS: Nodules of different legume species were used. Varied concentrations of guanidine thiocyanate (from 6 mol l(-1) to 0.05 mmol l(-1)), a component of DNAzol, were tested. The quality of DNA extract was determined by PCR-RFLP. The best results were obtained with 0.5 mmol l(-1) guanidine thiocyanate, which resulted in greater DNA yield than with higher and lower concentrations or with DNAzol. CONCLUSION: The procedure using 0.5 mmol l(-1) guanidine thiocyanate yields the highest DNA amount when compared with previously described protocols and offers a reliable method to isolate DNA from nodules of different origins. SIGNIFICANCE AND IMPACT OF THE STUDY: Irrespective of nodule origin, DNA yield was increased significantly, by two (e.g., Vigna nodules) to seven (Acacia auricoliformis nodules) times. In addition, the proposed procedure's costs are lower than those using the DNAzol.


Subject(s)
DNA, Bacterial/isolation & purification , Fabaceae/chemistry , Guanidines/pharmacology , Polymerase Chain Reaction/methods , Polymorphism, Restriction Fragment Length , Root Nodules, Plant/chemistry , Thiocyanates/pharmacology , DNA, Bacterial/analysis , Fabaceae/microbiology , Guanidines/chemistry , Nitrogen Fixation , Rhizobium/genetics , Rhizobium/growth & development , Root Nodules, Plant/microbiology , Symbiosis , Thiocyanates/chemistry
10.
J Appl Microbiol ; 100(3): 436-45, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16478483

ABSTRACT

AIMS: In order to understand the genetic diversity of Acacia tortilis ssp. raddiana-rhizobia in Tunisia, isolates from nine geographical locations were obtained and analysed. METHODS AND RESULTS: Characterization using restriction fragment length polymorphism analysis (RFLP) of PCR-amplified 16S rRNA gene and the intergenic spacer (IGS) between the 16S and 23S rRNA genes was undertaken. Symbiotic efficiency of the strains was also estimated. Analysis of the 16S rRNA by PCR-RFLP showed that the isolates were phylogenetically related to Ensifer ssp., Rhizobium tropicii-IIA, and Rhizobium tumefaciens species. Analysis of 16S-23S spacer by PCR-RFLP showed a high diversity of these rhizobia and revealed eleven additional groups, which indicates that these strains are genetically very diverse. Full 16S rRNA gene-sequencing showed that the majority of strains form a new subdivion inside the genera Ensifer, with Ensifer meliloti being its nearest neighbour. Nodulation test performed on the plant host demonstrated differences in the infectivity among the strains. CONCLUSION: Rhizobial populations that nodulate specifically and efficiently Acacia tortilis ssp. raddiana in representative soils of Tunisia is dominated by E. meliloti-like genomospecies. SIGNIFICANCE AND IMPACT OF THE STUDY: This paper provides the first clear characterization and symbiotic efficiency data of rhizobia strains nodulating A. tortilis in Tunisia.


Subject(s)
Acacia/genetics , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Rhizobium/genetics , Acacia/microbiology , DNA, Ribosomal Spacer/genetics , Genetic Variation/genetics , Phylogeny , Plant Diseases/genetics , Plant Roots/microbiology , Polymerase Chain Reaction/methods , Polymorphism, Restriction Fragment Length , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 23S/genetics , Rhizobium/isolation & purification , Sequence Analysis, RNA/methods , Symbiosis , Tunisia
11.
Mycorrhiza ; 15(5): 357-64, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15616831

ABSTRACT

Two strains of Bradyrhizobium sp., Aust 13C and Aust 11C, were dually or singly inoculated with an ectomycorrhizal fungus, Pisolithus albus to assess the interactions between ectomycorrhizal symbiosis and the nodulation process in glasshouse conditions. Sequencing of strains Aust 13C and Aust 11C confirmed their previous placement in the genus Bradyrhizobium. After 4 months' culture, the ectomycorrhizal symbiosis promoted plant growth and the nodulation process of both Bradyrhizobium strains, singly or dually inoculated. PCR/RFLP analysis of the nodules randomly collected in each treatment with Aust 13C and/or Aust 11C: (1) showed that all the nodules exhibited the same patterns as those of the Bradyrhizobium strains, and (2) did not detect contaminant rhizobia. When both Bradyrhizobium isolates were inoculated together, but without P. albus IR100, Aust 11C was recorded in 13% of the treated nodules compared to 87% for Aust 13C, whereas Aust 11C and Aust 13C were represented in 20 and 80% of the treated nodules, respectively, in the ectomycorrhizal treatment. Therefore Aust 13C had a high competitive ability and a great persistence in soil. The presence of the fungus did not significantly influence the frequencies of each Bradyrhizobium sp. root nodules. Although the mechanisms remain unknown, these results showed that the ectomycorrhizal and biological nitrogen-fixing symbioses were very dependent on each other. From a practical point of view, the role of ectomycorrhizal symbiosis is of great importance to N2 fixation and, consequently, these kinds of symbiosis must be associated in any controlled inoculation.


Subject(s)
Acacia/growth & development , Basidiomycota/growth & development , Bradyrhizobium/physiology , Mycorrhizae/growth & development , Nitrogen Fixation , Symbiosis , Acacia/microbiology , Basidiomycota/metabolism , Bradyrhizobium/classification , Bradyrhizobium/genetics , DNA, Bacterial/analysis , DNA, Ribosomal Spacer/analysis , Molecular Sequence Data , Plant Roots/microbiology , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , RNA, Ribosomal, 16S/genetics , RNA, Ribosomal, 23S/genetics
12.
Mycorrhiza ; 14(5): 313-22, 2004 Oct.
Article in English | MEDLINE | ID: mdl-14634857

ABSTRACT

This study was conducted to evaluate the competitiveness and effectiveness of Thelephoroid fungal sp. ORS.XM002 against native ectomycorrhizal fungal species colonizing potted Afzelia africana seedlings during 3 months of growth in different forest soils collected from under mature trees. Using morphotyping and restriction fragment length polymorphism (RFLP) analysis of the nuclear rDNA internal transcribed spacer (ITS), we were able to distinguish the introduced Thelephoroid fungal sp. ORS.XM002 among native ectomycorrhizal fungal species that form ectomycorrhizae in A. africana seedlings. The morphotype (MT) of the introduced fungus showed some color variation, with a shift from light- to dark-brown observed from younger to older mycorrhizal tips. We were able to differentiate the ITS type xm002 of the introduced fungus from the 14 ITS-RFLP types characterizing the 9 native MT that occurred in forest soils. The frequency of ITS type xm002 ranged from 40% to 49% depending on the forest soil used, and was always higher than those of ITS types from native dark-brown MT that occurred in inoculated seedlings 3 months after inoculation. We considered Thelephoroid fungal sp. ORS.XM002 to be responsible for stimulation of mycorrhizal colonization of inoculated A. africana seedlings when compared with control seedlings in forest soils. This fungus appeared to be more effective in increasing the root dry weight of A. africana seedlings. To identify the unknown introduced fungal species and native MT, we sequenced the ML5/ML6 region of the mitochondrial large subunit rRNA. Sequence analysis showed that these fungi belong to three ML5/ML6 groups closely related to the Cortinarioid, Thelephoroid, and Sclerodermataceous taxa. The molecular evidence for the persistence of Thelephoroid fungal sp. ORS.XM002 despite competition from native fungi argues in favor of using this fungus with A. africana in nursery soil conditions in Senegal.


Subject(s)
Fabaceae/microbiology , Mycorrhizae/physiology , Trees/microbiology , Basidiomycota/physiology , DNA, Fungal/genetics , Fabaceae/growth & development , Phylogeny , Plant Roots/microbiology , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Seedlings/growth & development , Seedlings/microbiology , Senegal , Soil Microbiology , Trees/growth & development
13.
Microb Ecol ; 45(2): 137-44, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12545310

ABSTRACT

The aim of the study was to assess the effect of the mycorrhizosphere of A. tortillis spp. raddiana mycorrhized with Glomus intraradices on the root nodulation by Sinorhizobium terangae (ORS 1009) and/or Mesorhizobium plurifarium (ORS 1096) in two different culture substrates (sandy soil and sand). The endomycorrhizal fungus only stimulated plant growth in the sandy soil. Moreover, arbuscular mycorrhizal infection enhanced the nodulation process in both culture substrates. Beside the stimulatory effects of the mycorrhizosphere on both rhizobia development, fungal symbiosis induces two different dynamics of each bacterial strains in the sand-grown plants. These results suggest specific relationships could occur during the development of the tripartite symbiosis, at physiological and molecular level. From a practical point of view, the role of arbuscular mycorrhizas in improving nodulation and N2 fixation is universally recognized. The fungal symbiosis could modify the development of bacterial inoculants along the root systems. This effect is of particular interest in the controlled inoculation of selected rhizobia.


Subject(s)
Acacia/growth & development , Acacia/microbiology , Fungi/growth & development , Rhizobiaceae/growth & development , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Fungi/metabolism , Mycorrhizae/growth & development , Plant Roots/growth & development , Plant Roots/microbiology , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Rhizobiaceae/metabolism , Sequence Analysis, DNA , Silicon Dioxide , Sinorhizobium/growth & development , Soil , Soil Microbiology , Symbiosis
14.
15.
J Bacteriol ; 183(1): 214-20, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11114919

ABSTRACT

Rhizobia described so far belong to three distinct phylogenetic branches within the alpha-2 subclass of Proteobacteria. Here we report the discovery of a fourth rhizobial branch involving bacteria of the Methylobacterium genus. Rhizobia isolated from Crotalaria legumes were assigned to a new species, "Methylobacterium nodulans," within the Methylobacterium genus on the basis of 16S ribosomal DNA analyses. We demonstrated that these rhizobia facultatively grow on methanol, which is a characteristic of Methylobacterium spp. but a unique feature among rhizobia. Genes encoding two key enzymes of methylotrophy and nodulation, the mxaF gene, encoding the alpha subunit of the methanol dehydrogenase, and the nodA gene, encoding an acyltransferase involved in Nod factor biosynthesis, were sequenced for the type strain, ORS2060. Plant tests and nodA amplification assays showed that "M. nodulans" is the only nodulating Methylobacterium sp. identified so far. Phylogenetic sequence analysis showed that "M. nodulans" NodA is closely related to Bradyrhizobium NodA, suggesting that this gene was acquired by horizontal gene transfer.


Subject(s)
Fabaceae/microbiology , Methanol/metabolism , Methylobacterium/classification , Methylobacterium/physiology , Nitrogen Fixation/physiology , Plants, Medicinal , Symbiosis , Acyltransferases/genetics , Alcohol Oxidoreductases/genetics , Bacterial Proteins , DNA, Bacterial/analysis , DNA, Bacterial/genetics , DNA, Ribosomal/analysis , DNA, Ribosomal/genetics , Methylobacterium/genetics , Methylobacterium/isolation & purification , Molecular Sequence Data , Oxidation-Reduction , Phylogeny , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Species Specificity
16.
Int J Syst Evol Microbiol ; 50 Pt 5: 1893-1898, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11034501

ABSTRACT

A high-resolution phylogenetic analysis of Nitrobacter strains and their neighbours was made using the rrs-rrl intergenic spacer sequence and the hypervariable part of the rrl gene. The phylogenetic tree obtained was consistent with that which was obtained previously but was much more discriminating, permitting the design of genus-specific primers.


Subject(s)
DNA, Ribosomal Spacer/genetics , Genes, rRNA , Nitrites/metabolism , Nitrobacter/classification , Nitrobacter/genetics , RNA, Ribosomal, 23S/genetics , DNA Primers , DNA, Bacterial/genetics , Molecular Sequence Data , Nitrobacter/metabolism , Oxidation-Reduction , Phylogeny , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
17.
Int J Syst Evol Microbiol ; 50 Pt 1: 159-170, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10826800

ABSTRACT

Fifty-eight new isolates were obtained from root nodules of common bean (Phaseolus vulgaris) cultivated in soils originating from different agroecological areas in Senegal and Gambia (West Africa). A polyphasic approach including both phenotypic and genotypic techniques was used to study the diversity of the 58 Rhizobium isolates and to determine their taxonomic relationships with reference strains. All the techniques performed, analysis of multilocus enzyme electrophoretic patterns, SDS-PAGE profiles of total cell proteins, PCR-RFLP analysis of the genes encoding 16S rRNA and of the 16S-23S RNA intergenic spacer region (ITS-PCR-RFLP), auxanographic tests using API galleries and nodulation tests lead to the consensus conclusion that the new rhizobial isolates formed two main distinct groups, I and II, belonging to Rhizobium tropici type B and Rhizobium etli, respectively. By MLEE R. etli and group II strains showed several related electrophoretic types, evidencing some extent of internal heterogeneity among them. This heterogeneity was confirmed by other techniques (ITS-PCR-RFLP, SDS-PAGE and host-plant-specificity) with the same nine distinct strains of group II showing some differences from the core of group II (54 strains).


Subject(s)
Fabaceae/microbiology , Nitrogen Fixation , Plants, Medicinal , Rhizobium/classification , Bacterial Proteins/analysis , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Electrophoresis, Polyacrylamide Gel , Enzymes/analysis , Gambia , Genes, rRNA , Plant Roots/microbiology , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , RNA, Ribosomal, 16S/genetics , Rhizobium/genetics , Rhizobium/isolation & purification , Rhizobium/physiology , Senegal
18.
Int J Cancer ; 82(5): 635-9, 1999 Aug 27.
Article in English | MEDLINE | ID: mdl-10417758

ABSTRACT

The mutator (RER(+)) phenotype has been shown to be a mutational mechanism for tumour-suppressor-gene inactivation in colorectal cancer. A group of 60 prostate-carcinoma patients was studied to determine the frequency, intratumour distribution and timing of mutator phenotype in this cancer. Ten microsatellite loci were analyzed in 172 carcinoma foci (CF) and in 57 associated non-cancerous prostate tissues, including 31 areas of prostate intra-epithelial neoplasia (PIN) and 26 non-dysplastic areas with glandular hyperplasia (HP). We detected lesions with the RER(+) phenotype in 42% (25/60) of the prostate tumours. Clonal foci with RER(+) phenotype were detected at similar frequencies in pre-cancereous PIN (16%, 5/31) as in associated carcinoma foci (22%, 37/172), but were detected in only one of the 26 non-dysplastic prostate tissues studied (4%). Thus, clonal RER(+) foci were significantly more frequent in CF than in HP (p < 0.05). MI itself was significantly more frequent in CF (53%, p < 0.0001) and in PIN (35%, p < 0.05) than in HP (12%). Furthermore, 5 PIN harboured microsatellite mutations also detected in the associated cancer. Our overall results therefore strongly suggest that the mutator phenotype may occur as an early event in prostate tumorigenesis.


Subject(s)
Prostatic Intraepithelial Neoplasia/genetics , Prostatic Neoplasms/genetics , Carcinogenicity Tests , Gene Frequency , Genes, Tumor Suppressor , Humans , Hyperplasia , Male , Microsatellite Repeats/genetics , Phenotype
19.
Prog Urol ; 8(4): 565-8, 1998 Sep.
Article in French | MEDLINE | ID: mdl-9834523

ABSTRACT

A 57 year-old patient with localized pseudo-tumoral amyloidosis of bladder is described. There was no past medical history. Hematuria was the main symptom. The treatment consisted in transurethral resection. Two recurrences occurred at 4 and at 6 years which were also treated by resections. Clinical and biological evaluation was normal. Localized pseudo-tumoral amyloidosis of the urinary tract is a rare affection of good prognosis. Lesions present as pseudo-tumoral masses which can be biopsied without any risk of hematuria. Investigations are required to eliminate a generalized amyloidosis or a malignant lymphoproliferation. Treatment should be as conservative as possible.


Subject(s)
Amyloidosis/diagnosis , Urinary Bladder Diseases/diagnosis , Amyloidosis/complications , Amyloidosis/pathology , Humans , Male , Middle Aged , Recurrence , Urinary Bladder Diseases/complications , Urinary Bladder Diseases/pathology
20.
Appl Environ Microbiol ; 64(12): 4912-7, 1998 Dec.
Article in English | MEDLINE | ID: mdl-9835582

ABSTRACT

Forty rhizobia nodulating four Acacia species (A. gummifera, A. raddiana, A. cyanophylla, and A. horrida) were isolated from different sites in Morocco. These rhizobia were compared by analyzing both the 16S rRNA gene (rDNA) and the 16S-23S rRNA spacer by PCR with restriction fragment length polymorphism (RFLP) analysis. Analysis of the length of 16S-23S spacer showed a considerable diversity within these microsymbionts, but RFLP analysis of the amplified spacer revealed no additional heterogeneity. Three clusters were identified when 16S rDNA analysis was carried out. Two of these clusters include some isolates which nodulate, nonspecifically, the four Acacia species. These clusters, A and B, fit within the Sinorhizobium lineage and are closely related to S. meliloti and S. fredii, respectively. The third cluster appeared to belong to the Agrobacterium-Rhizobium galegae phylum and is more closely related to the Agrobacterium tumefaciens species. These relations were confirmed by sequencing a representative strain from each cluster.

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