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1.
Eur J Clin Microbiol Infect Dis ; 31(5): 683-94, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21805195

RESUMO

We investigated the presence of nontuberculous mycobacteria (NTM) in three Mexican aquatic systems to evaluate the prevalence with the distribution of NTM species. Key physicochemical parameters of the water samples were determined to find correlations with the species' distributions. We used multilocus sequence analysis (MLSA) based on hsp65, rpoB, and 16S rRNA fragments to determine their taxonomic affiliations. NTM were recovered from water distribution systems and reclaimed water from the Mexico City Metropolitan Area (MCMA). The isolated species were associated with a temperature of 21°C and pH >7.7. The phylogenetic analysis showed that eight of the 14 different NTM strains were unambiguously classifiable: Mycobacterium peregrinum, M. nonchromogenicum (2), M. smegmatis (2), M. fortuitum, M. avium ssp. hominissuis, M. arupense, M. gordonae, and M. chitae. One strain was tentatively identified as M. mantenni/ scrofulaceum and another strain was related to M. porcinum/M. septicum. All NTM species identified in the water distribution system were also detected in the reclaimed water, but some species from the reclaimed water were not found in the water distribution systems. Two of the identified species found in the reclaimed water, M. avium and M. fortuitum, are considered important human opportunistic pathogens.


Assuntos
Água Doce/microbiologia , Micobactérias não Tuberculosas/classificação , Micobactérias não Tuberculosas/isolamento & purificação , Proteínas de Bactérias/genética , Chaperonina 60/genética , RNA Polimerases Dirigidas por DNA/genética , Água Doce/química , Concentração de Íons de Hidrogênio , México , Dados de Sequência Molecular , Micobactérias não Tuberculosas/genética , Prevalência , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Temperatura
2.
Appl Environ Microbiol ; 67(8): 3655-64, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11472944

RESUMO

In addition to forming symbiotic nodules on legumes, rhizobial strains are members of soil or rhizosphere communities or occur as endophytes, e.g., in rice. Two rhizobial strains which have been isolated from root nodules of the aquatic legumes Aeschynomene fluminensis (IRBG271) and Sesbania aculeata (IRBG74) were previously found to promote rice growth. In addition to analyzing their phylogenetic positions, we assessed the suitability of the 16S-23S ribosomal DNA (rDNA) intergenic spacer (IGS) sequences for the differentiation of closely related rhizobial taxa and for the development of PCR protocols allowing the specific detection of strains in the environment. 16S rDNA sequence analysis (sequence identity, 99%) and phylogenetic analysis of IGS sequences showed that strain IRBG271 was related to but distinct from Bradyrhizobium elkanii. Rhizobium sp. (Sesbania) strain IRBG74 was located in the Rhizobium-Agrobacterium cluster as a novel lineage according to phylogenetic 16S rDNA analysis (96.8 to 98.9% sequence identity with Agrobacterium tumefaciens; emended name, Rhizobium radiobacter). Strain IRBG74 harbored four copies of rRNA operons whose IGS sequences varied only slightly (2 to 9 nucleotides). The IGS sequence analyses allowed intraspecies differentiation, especially in the genus Bradyrhizobium, as illustrated here for strains of Bradyrhizobium japonicum, B. elkanii, Bradyrhizobium liaoningense, and Bradyrhizobium sp. (Chamaecytisus) strain BTA-1. It also clearly differentiated fast-growing rhizobial species and strains, albeit with lower statistical significance. Moreover, the high sequence variability allowed the development of highly specific IGS-targeted nested-PCR assays. Strains IRBG74 and IRBG271 were specifically detected in complex DNA mixtures of numerous related bacteria and in the DNA of roots of gnotobiotically cultured or even of soil-grown rice plants after inoculation. Thus, IGS sequence analysis is an attractive technique for both microbial ecology and systematics.


Assuntos
Bradyrhizobium/isolamento & purificação , DNA Espaçador Ribossômico/análise , Oryza/microbiologia , Raízes de Plantas/microbiologia , Reação em Cadeia da Polimerase/métodos , Rhizobium/isolamento & purificação , Bradyrhizobium/classificação , Bradyrhizobium/genética , Bradyrhizobium/crescimento & desenvolvimento , Primers do DNA , Dados de Sequência Molecular , Oryza/crescimento & desenvolvimento , Filogenia , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Rhizobium/classificação , Rhizobium/genética , Rhizobium/crescimento & desenvolvimento , Análise de Sequência de DNA
3.
Syst Appl Microbiol ; 23(3): 418-25, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11108022

RESUMO

Thirty-six strains of slow-growing rhizobia isolated from nodules of four woody legumes endemic to the Canary islands were characterised by 16S rDNA PCR-RFLP analyses (ARDRA) and LMW RNA profiling, and compared with reference strains representing Bradyrhizobium japonicum, B. elkanii, B. liaoningense, and two unclassified Bradyrhizobium sp. (Lupinus) strains. Both techniques showed similar results, indicating the existence of three genotypes among the Canarian isolates. Analysis of the combined RFLP patterns obtained with four endonucleases, showed the existence of predominant genotype comprising 75% of the Canarian isolates (BTA-1 group) and the Bradyrhizobium sp. (Lupinus) strains. A second genotype was shared by nine Canarian isolates (BGA-1 group) and the B. japonicum and B. liaoningense reference strains. The BES-5 strain formed an independent group, as also did the B. elkanii reference strains. LMW RNA profile analysis consistently resolved the same three genotypes detected by 16S ARDRA among the Canarian isolates, and suggested that all these isolates are genotypically more related to B. japonicum than to B. elkanii or B. liaoningense. Cluster analysis of the combined 16S ARDRA and LMW RNA profiles resolved the BTA-1 group with the Bradyrhizobium sp. (Lupinus) strains, and the BES-5 isolate, as a well separated sub-branch of the B. japonicum cluster. Thus, the two types of analyses indicated that the isolates related to BTA-1 conform a group of bradyrhizobial strains that can be clearly distinguishable from representatives of the tree currently described Bradyrhizobium species. No correlation between genotypes, host legumes, and geographic location was found.


Assuntos
Bradyrhizobium/genética , DNA Ribossômico/genética , Fabaceae/microbiologia , Plantas Medicinais , Polimorfismo de Fragmento de Restrição , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Bradyrhizobium/classificação , Análise por Conglomerados , Geografia , Espanha
4.
Rev Esp Cardiol ; 53(11): 1474-95, 2000 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-11084006

RESUMO

Maternal adaptation to pregnancy includes reproductive hormone interaction plasma, volume changes with an increase in total body water, vascular alterations with a decrease in systemic resistance and modifications associated with hypercoagulability. These explain, in part, the appearance of signs and symptoms, even in a normal pregnant woman, that are difficult to distinguish from those occurring in heart disease and why some cardiac abnormalities are not well tolerated during pregnancy. Cardiovascular abnormalities are considered the first non-obstetric cause of morbidity and mortality during pregnancy. Rheumatic and congenital heart diseases are currently the most frequent cardiopathy found in women of childbearing age, followed by hypertension, coronary artery disease and arrhythmia. Although pregnancy is well tolerated by most women with heart disease, there are some cardiovascular abnormalities which place the mother and the infant at extremely high risk: patients with congestive heart failure and severe cardiac dysfunction, pulmonary hypertension, cyanotic congenital heart disease, Marfan's syndrome, severe obstructive lesions of the left side of the heart, patients with prosthetic cardiac valves and antecedents of peripartum cardiomyopathy should be encouraged to avoid pregnancy and the interruption of pregnancy may be advisable in cases with great risk of disability or death. The most severe cardiopathies significantly increase the risk of fetal loss and the presence of a congenital cardiac abnormality in either parent increases the risk of congenital cardiac disease in the fetus. Medical care must be initiated early, prior to conception and women with cardiopathy should be informed of the possible risks of pregnancy to both the mother and fetus.


Assuntos
Complicações Cardiovasculares na Gravidez/terapia , Fatores Etários , Anticoagulantes/uso terapêutico , Cardiotônicos/uso terapêutico , Fenômenos Fisiológicos Cardiovasculares , Endocardite Bacteriana/prevenção & controle , Feminino , Doenças Fetais/epidemiologia , Doenças Fetais/etiologia , Cardiopatias Congênitas/complicações , Doenças das Valvas Cardíacas/terapia , Próteses Valvulares Cardíacas , Humanos , Gravidez , Fatores de Risco
5.
Rev Esp Cardiol ; 52(9): 737-40, 1999 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-10523889

RESUMO

The development of a pseudoaneurysms of the ascending aorta is a potential complication after composite grafts surgery for combined disorders that simultaneously affect the aortic valve and ascending aorta. Pseudoaneurysm has been reported to range from 7% to 25% of cases, and it is due to dehiscence of the suture line at anastomosis. Clinical spectrum, which depends on the location of this dehiscence varies from the totally asymptomatic patient to one with NYHA class IV heart failure, with the possibility of its clinical status rapidly worsening. We report a case of progressive haemodynamic deterioration as a consequence of a peri-annular dehiscence that led to a significant regurgitant volume from the pseudoaneurysm cavity to the left ventricle mimicking a severe aortic insufficiency. The role of echocardiography is reviewed in the diagnosis and the management of complications, as well as the necessary follow up of patients with composite aortic grafts.


Assuntos
Falso Aneurisma/etiologia , Aorta/cirurgia , Aneurisma Aórtico/etiologia , Insuficiência da Valva Aórtica/diagnóstico , Prótese Vascular , Próteses Valvulares Cardíacas , Idoso , Falso Aneurisma/diagnóstico , Aneurisma Aórtico/diagnóstico , Valva Aórtica , Diagnóstico Diferencial , Ecocardiografia Transesofagiana , Eletrocardiografia , Humanos , Masculino , Suturas/efeitos adversos
6.
J Bacteriol ; 181(18): 5606-14, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10482500

RESUMO

Screening of derivatives of Rhizobium etli KIM5s randomly mutagenized with mTn5SSgusA30 resulted in the identification of strain KIM-G1. Its rough colony appearance, flocculation in liquid culture, and Ndv(-) Fix(-) phenotype were indicative of a lipopolysaccharide (LPS) defect. Electrophoretic analysis of cell-associated polysaccharides showed that KIM-G1 produces only rough LPS. Composition analysis of purified LPS oligosaccharides from KIM-G1 indicated that it produces an intact LPS core trisaccharide (alpha-D-GalA-1-->4[alpha-D-GalA-1-->5]-Kdo) and tetrasaccharide (alpha-D-Gal-1-->6[alpha-D-GalA-1-->4]-alpha-D-Man-1-->5Kdo), strongly suggesting that the transposon insertion disrupted a locus involved in O-antigen biosynthesis. Five monosaccharides (Glc, Man, GalA, 3-O-Me-6-deoxytalose, and Kdo) were identified as the components of the repeating O unit of the smooth parent strain, KIM5s. Strain KIM-G1 was complemented with a 7.2-kb DNA fragment from KIM5s that, when provided in trans on a broad-host-range vector, restored the smooth LPS and the full capacity of nodulation and fixation on its host Phaseolus vulgaris. The mTn5 insertion in KIM-G1 was located at the N terminus of a putative alpha-glycosyltransferase, which most likely had a polar effect on a putative beta-glycosyltransferase located downstream. A third open reading frame with strong homology to sugar epimerases and dehydratases was located upstream of the insertion site. The two glycosyltransferases are strain specific, as suggested by Southern hybridization analysis, and are involved in the synthesis of the variable portion of the LPS, i.e., the O antigen. This newly identified LPS locus was mapped to a 680-kb plasmid and is linked to the lpsbeta2 gene recently reported for R. etli CFN42.


Assuntos
Fabaceae/microbiologia , Lipopolissacarídeos/biossíntese , Antígenos O/biossíntese , Oligossacarídeos/biossíntese , Plantas Medicinais , Plasmídeos , Rhizobium/fisiologia , Sequência de Bases , Sequência de Carboidratos , Conjugação Genética , Fabaceae/fisiologia , Teste de Complementação Genética , Lipopolissacarídeos/química , Dados de Sequência Molecular , Mutagênese Insercional , Antígenos O/química , Oligossacarídeos/química , Fases de Leitura Aberta , Regiões Promotoras Genéticas , Mapeamento por Restrição , Rhizobium/genética , Trissacarídeos/biossíntese , Trissacarídeos/química
7.
Z Naturforsch C J Biosci ; 54(5-6): 359-70, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10431388

RESUMO

A DNA probe specific for biocontrol strains of Pseudomonas was produced by screening randomly amplified polymorphic DNA (RAPD) PCR fragments. Specificity of the probe was assessed by dot blot and colony hybridization. It was used to specifically determine the population of these strains on roots of Cucumis sativus cv. Delikatess. Two polymorphic RAPD fragments of 750 bp, and 550 bp showed identical specificity. The biocontrol strain Pseudomonas sp. W34 was shown to be competitive in the rhizosphere of cucumber and to maintain a stable population for at least 10 days when inoculated on the seed. The phylogenetic relationships between the biocontrol and reference strains were analyzed at the strain level by means of RAPD and repetitive sequence-based PCR genomic fingerprinting (rep-PCR), and at higher taxonomic levels by means of amplified 16S ribosomal DNA restriction analysis ARDRA. It was shown that the antagonistic strains are closely related, forming a separate cluster from other non-antagonistic and reference Pseudomonas strains, their taxonomic placement remaining uncertain.


Assuntos
Cucumis sativus/microbiologia , Controle Biológico de Vetores , Filogenia , Pseudomonas/classificação , Impressões Digitais de DNA , Sondas de DNA , Genótipo , Raízes de Plantas/microbiologia , Pseudomonas/genética , Pseudomonas/isolamento & purificação , Técnica de Amplificação ao Acaso de DNA Polimórfico
8.
Rev Esp Cardiol ; 52(1): 59-62, 1999 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-9989141

RESUMO

We report a case of a 72-year-old woman with coronary artery disease in whom a thrombus in transit in the right atrium was diagnosed accidentally. After 72 hours of treatment with intravenous anticoagulants she developed a pulmonary thromboembolism resolved with systemic fibrinolysis. This is a rare case in which such a diagnosis preceded an embolic event. This fact raises the controversy about the best therapeutic management of this unusual form of thromboembolic illness.


Assuntos
Ecocardiografia , Cardiopatias/diagnóstico por imagem , Embolia Pulmonar/diagnóstico por imagem , Trombose/diagnóstico por imagem , Idoso , Anticoagulantes/uso terapêutico , Quimioterapia Combinada , Feminino , Átrios do Coração/diagnóstico por imagem , Cardiopatias/complicações , Cardiopatias/tratamento farmacológico , Humanos , Embolia Pulmonar/tratamento farmacológico , Embolia Pulmonar/etiologia , Terapia Trombolítica , Trombose/complicações , Trombose/tratamento farmacológico , Fatores de Tempo
9.
Rev Esp Cardiol ; 51(4): 336-9, 1998 Apr.
Artigo em Espanhol | MEDLINE | ID: mdl-9608807

RESUMO

Wegener's granulomatosis (WG) is a necrotizing and granulomatous vasculitis that usually affects the upper and lower respiratory tract and the kidneys. Cardiac involvement is rare although pericarditis, coronary arteritis, myocarditis, valvulitis and arrhythmias have been described. Acute myocardial infarction with clinical expression is an exceptional complication of Wegener's granulomatosis. We report a case of a 30-year-old man with Wegener's granulomatosis who suffered an acute myocardial infarction during the initial phase of the disease, following seven days of treatment with glucocorticoids and cyclophosphamide. Transthoracic echocardiography showed abnormal regional wall motion with septal hypokinesia and apical akinesia. Cardiac catheterization revealed an ectasic segment in the proximal left anterior descending coronary artery and total occlusion in the mid-segment. Medical therapy with prednisone and cyclophosphamide was continued. No complications and initial remission were achieved.


Assuntos
Granulomatose com Poliangiite/complicações , Infarto do Miocárdio/etiologia , Adulto , Anti-Inflamatórios/uso terapêutico , Angiografia Coronária , Ciclofosfamida/uso terapêutico , Eletrocardiografia , Granulomatose com Poliangiite/tratamento farmacológico , Humanos , Imunossupressores/uso terapêutico , Masculino , Infarto do Miocárdio/diagnóstico , Prednisona/uso terapêutico
10.
Appl Environ Microbiol ; 64(6): 2096-104, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9603820

RESUMO

We present a phylogenetic analysis of nine strains of symbiotic nitrogen-fixing bacteria isolated from nodules of tagasaste (Chamaecytisus proliferus) and other endemic woody legumes of the Canary Islands, Spain. These and several reference strains were characterized genotypically at different levels of taxonomic resolution by computer-assisted analysis of 16S ribosomal DNA (rDNA) PCR-restriction fragment length polymorphisms (PCR-RFLPs), 16S-23S rDNA intergenic spacer (IGS) RFLPs, and repetitive extragenic palindromic PCR (rep-PCR) genomic fingerprints with BOX, ERIC, and REP primers. Cluster analysis of 16S rDNA restriction patterns with four tetrameric endonucleases grouped the Canarian isolates with the two reference strains, Bradyrhizobium japonicum USDA 110spc4 and Bradyrhizobium sp. strain (Centrosema) CIAT 3101, resolving three genotypes within these bradyrhizobia. In the analysis of IGS RFLPs with three enzymes, six groups were found, whereas rep-PCR fingerprinting revealed an even greater genotypic diversity, with only two of the Canarian strains having similar fingerprints. Furthermore, we show that IGS RFLPs and even very dissimilar rep-PCR fingerprints can be clustered into phylogenetically sound groupings by combining them with 16S rDNA RFLPs in computer-assisted cluster analysis of electrophoretic patterns. The DNA sequence analysis of a highly variable 264-bp segment of the 16S rRNA genes of these strains was found to be consistent with the fingerprint-based classification. Three different DNA sequences were obtained, one of which was not previously described, and all belonged to the B. japonicum/Rhodopseudomonas rDNA cluster. Nodulation assays revealed that none of the Canarian isolates nodulated Glycine max or Leucaena leucocephala, but all nodulated Acacia pendula, C. proliferus, Macroptilium atropurpureum, and Vigna unguiculata.


Assuntos
DNA Bacteriano/genética , DNA Ribossômico/genética , Genes Bacterianos , Rhizobiaceae/genética , Ilhas Atlânticas , Sequência de Bases , Clonagem Molecular , Impressões Digitais de DNA , Primers do DNA/genética , Fabaceae/microbiologia , Plantas Medicinais , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Rhizobiaceae/isolamento & purificação
11.
Rev Esp Cardiol ; 50(8): 597-9, 1997 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-9340703

RESUMO

We report a case of a 58-year-old woman with rheumatic mitral stenosis scheduled for percutaneous valvuloplasty. Prior left and right ventricular angiograms showed multiple diverticula at left ventricular apical and diaphragmatic walls and right ventricular diaphragmatic wall. Chest x-ray and echocardiogram were normal. Magnetic resonance imaging was concordant with catheterization findings and ruled out other cardiac malformations. The risk of ventricular perforation changed our indication of percutaneous valvuloplasty in favor of open heart commissurotomy.


Assuntos
Estenose da Valva Mitral/complicações , Cardiopatia Reumática/complicações , Disfunção Ventricular Esquerda , Procedimentos Cirúrgicos Cardíacos/métodos , Divertículo/etiologia , Divertículo/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Estenose da Valva Mitral/cirurgia , Cardiopatia Reumática/cirurgia , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/cirurgia
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