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1.
J Clin Microbiol ; 56(2)2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29167292

RESUMO

Trichomoniasis is the most prevalent curable sexually transmitted disease (STD). It has been associated with preterm birth and the acquisition and transmission of HIV. Recently, nucleic acid amplification tests (NAAT) have been FDA cleared in the United States for detection of Trichomonas vaginalis in specimens from both women and men. This study reports the results of a multicenter study recently conducted using the Xpert TV (T. vaginalis) assay to test specimens from both men and women. On-demand results were available in as little as 40 min for positive specimens. A total of 1,867 women and 4,791 men were eligible for inclusion in the analysis. In women, the performance of the Xpert TV assay was compared to the patient infected status (PIS) derived from the results of InPouch TV broth culture and Aptima NAAT for T. vaginalis The diagnostic sensitivities and specificities of the Xpert TV assay for the combined female specimens (urine samples, self-collected vaginal swabs, and endocervical swabs) ranged from 99.5 to 100% and 99.4 to 99.9%, respectively. For male urine samples, the diagnostic sensitivity and specificity were 97.2% and 99.9%, respectively, compared to PIS results derived from the results of broth culture for T. vaginalis and bidirectional gene sequencing of amplicons. Excellent performance characteristics were seen using both female and male specimens. The ease of using the Xpert TV assay should result in opportunities for enhanced screening for T. vaginalis in both men and women and, hopefully, improved control of this infection.


Assuntos
Tricomoníase/diagnóstico , Trichomonas vaginalis/genética , Trichomonas vaginalis/isolamento & purificação , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Amplificação de Ácido Nucleico , Prevalência , Estudos Prospectivos , Sensibilidade e Especificidade , Manejo de Espécimes , Tricomoníase/epidemiologia , Tricomoníase/parasitologia , Estados Unidos/epidemiologia , Urina/parasitologia , Vagina/parasitologia , Adulto Jovem
3.
Ir J Psychol Med ; 40(2): 184-191, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-33228823

RESUMO

OBJECTIVES: There is a high rate of psychiatric comorbidity in patients with epilepsy. However, the impact of surgical treatment of refractory epilepsy on psychopathology remains under investigation. We aimed to examine the impact of epilepsy surgery on psychopathology and quality of life at 1-year post-surgery in a population of patients with epilepsy refractory to medication. METHODS: This study initially assessed 48 patients with refractory epilepsy using the Structured Clinical Interview for DSM-IV Axis I Disorders (SCID-I), the Hospital Anxiety and Depression Scale (HADS) and the Quality of Life in Epilepsy Inventory 89 (QOLIE-89) on admission to an Epilepsy Monitoring Unit (EMU) as part of their pre-surgical assessment. These patients were again assessed using the SCID-I, QOLIE-89 and HADS at 1-year follow-up post-surgery. RESULTS: There was a significant reduction in psychopathology, particularly psychosis, following surgery at 1-year follow-up (p < 0.021). There were no new cases of de novo psychosis and surgery was also associated with a significant improvement in the quality of life scores (p < 0.001). CONCLUSIONS: This study demonstrates the impact of epilepsy surgery on psychopathology and quality of life in a patient population with refractory surgery. The presence of a psychiatric illness should not be a barrier to access surgical treatment.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsia , Humanos , Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia Resistente a Medicamentos/psicologia , Qualidade de Vida/psicologia , Resultado do Tratamento , Epilepsia/cirurgia , Epilepsia/epidemiologia , Epilepsia/psicologia , Morbidade
4.
Mol Plant Microbe Interact ; 7(1): 78-90, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7909458

RESUMO

The syrB and syrD genes of Pseudomonas syringae pv. syringae are predicted to encode proteins that function in the synthesis and export of syringomycin, respectively. Using portions of the syr genes as DNA probes, both genes were shown to be conserved as single copies within a 15-kb or smaller DNA region among a broad spectrum of P. s. pv. syringae strains that produce syringomycin or one of its amino acid analogs, syringotoxin and syringostatin. Strains representative of P. viridiflava and six pathovars of P. syringae failed to hybridize with the gene probes, demonstrating that syr sequences are highly specific to P. s. pv. syringae and related nonpathogenic strains. Maximum parsimony analysis of restriction fragment length polymorphism profiles was used to evaluate relatedness among strains within the syrB and syrD gene region. A tree, conveying the smallest number of evolutionary changes among strains, revealed considerable diversity within the syr gene region; subclusters of strains were identified that appear to share specific qualities relevant to the plant-pathogen interaction. Because both the syrB gene and syringomycin production can be induced in response to plant signal molecules, 42 strains containing homologous syr sequences were tested for signal-mediated induction of toxin production. Over 90% of the toxigenic strains produced larger quantities of toxin when the plant signal molecules, arbutin and D-fructose, were added to syringomycin-minimal medium; 13 of the strains produced > or = 10-fold higher toxin levels. Some strains, such as 5D428, produced toxin only in the presence of these signals.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Proteínas de Bactérias/biossíntese , Proteínas de Transporte/biossíntese , Genes Bacterianos , Fenômenos Fisiológicos Vegetais , Polimorfismo de Fragmento de Restrição , Pseudomonas/genética , Pseudomonas/metabolismo , Toxinas Biológicas/biossíntese , Transportadores de Cassetes de Ligação de ATP , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Southern Blotting , Proteínas de Transporte/genética , DNA Bacteriano/análise , DNA Bacteriano/metabolismo , Dados de Sequência Molecular , Plantas/microbiologia , Plasmídeos , Pseudomonas/patogenicidade , Mapeamento por Restrição , Virulência/genética
5.
J Psychopharmacol ; 10(2): 146-52, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22302892

RESUMO

Both antipsychotic and anticholinergic drugs have been implicated in the production of the memory deficits seen in schizophrenia. We compared the effects of chlorpromazine (50 mg) and benzhexol (5 mg) with placebo on a battery of tests of memory, psychomotor function and mood, in 12 healthy volunteers. Benzhexol, but not chlorpromazine, impaired both word recall and word recognition. Neither drug had an effect on long-term memory Both active compounds were associated with self-rated sedation, and chlorpromazine produced impairment in saccadic eye movements. This study supports the contention that sedation is unlikely to be the mechanism by which anticholinergic drugs exert their amnestic effect.

6.
Arch Otolaryngol Head Neck Surg ; 117(4): 390-5, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2007007

RESUMO

Both autogenous bone grafts and demineralized freeze-dried allogeneic bone implants were evaluated for mandibular reconstruction. Four-centimeter segmental defects of the midbody of the edentulous mandible were reconstructed in 36 dogs, with specimens recovered at 3 and 6 months and quantitatively compared for total and new bone by histomorphometric analysis. Autogenous grafts consisted of corticocancellous cranial block (CB), corticocancellous iliac block (IB), and particulate cancellous iliac marrow (PM). The allogeneic bone was demineralized and freeze-dried, and consisted of particulate cortical endochondral bone (FP), cranial cortical block (FCB), and iliac cortical block (FIB). Clinically and histomorphometrically, results appeared to indicate that (1) CB compared favorably with IB at 3 and 6 months for total bone, but IB showed a trend for more new bone formation at 6 months, a trend that may be due to the thicker cortical component of CB, which requires longer time periods to remodel than the cancellous rich IB; (2) FP failed to achieve bony union at 3 months, with inadequate rates of new bone formation; and (3) FCB and FIB compared favorably for total bone with CB and IB at 6 months, although new bone for autogenous CB and IB was 26.9% and 45.4%, while new bone for allogeneic FCB and FIB represented only 7.9% and 17.4%.


Assuntos
Transplante Ósseo , Mandíbula/cirurgia , Preservação de Tecido , Animais , Transplante Ósseo/métodos , Cães , Feminino , Liofilização , Ílio , Masculino , Mandíbula/patologia , Crânio , Transplante Autólogo , Transplante Homólogo
7.
Hum Psychopharmacol ; 15(3): 171-177, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12404330

RESUMO

Benzodiazepines and other psychotropic drugs have been implicated in the production of memory deficits. The mechanism is unclear, but both a distinct pharmacological action and a non-specific sedative effect have been suggested as being causal or contributory. These two postulated mechanisms of action may be examined separately by using sleep deprivation as a method of non-pharmacological sedation. We measured psychomotor and memory functions in eight sleep-deprived healthy volunteers and eight controls. There was both subjective and objective evidence of sedation, but memory function was not affected. These findings support the view that the effect on memory of psychotropic drugs is principally caused by a direct amnestic effect rather than by drug-induced sedation. Copyright 2000 John Wiley & Sons, Ltd.

8.
J Endod ; 18(11): 530-4, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1298788

RESUMO

Numerous methods of root canal preparation have been recommended and used by clinicians. This study used histomorphometrics to determine the area of root canal preparations using four currently popular techniques. Clinicians that were highly skilled in each technique prepared curved canals in acrylic blocks. Each clinician described this technique and discussed the technique with regard to the use of acrylic blocks as compared with dentin. Analysis of the areas of the root canals after preparation revealed a significant difference among the groups. The mean areas after treatment were step-back technique, 17.33 mm2; Cavi-Endo technique, 15.87 mm2; Canal Master technique, 13.56 mm2; and balanced force technique, 17.31 mm2. Photographs of the blocks used in the study were included for inspection by the reader.


Assuntos
Preparo da Cavidade Dentária/métodos , Tratamento do Canal Radicular/métodos , Humanos
9.
Plast Reconstr Surg ; 91(4): 581-8, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8446710

RESUMO

The regeneration of bone with a biodegradable, biocompatible carrier and osteo-regenerative proteins may be possible if the carrier has the appropriate architecture to support osteoconduction and prevent soft-tissue prolapse into ablated bone segments. Using radiomorphometry and histomorphometry, our group assessed individually and combined the components of a multiphase system bone implant (MSI) in rabbit cranial defects (critical-size defects: CSDs): two disks of biodegradable polymer (PLG) and demineralized bone matrix (DBM), a recognized osteo-regenerative material. We used 48 rabbits evenly divided between four treatment groups and two time periods. Six weeks after treatment, both DBM and PLG had significant positive effects on bone regeneration (based on a three-factor analysis of variance, p < 0.05). These effects were synergistic when the components were combined (MSI). Defects treated with DBM or PLG alone continued to regenerate bone through 12 weeks. By this time, bone within the defects treated with MSI appeared to be maturing and consolidating. We conclude that the concept of placing osteo-regenerative factors between two biodegradable disks for regenerating segments of calvaria is viable.


Assuntos
Materiais Biocompatíveis , Matriz Óssea , Ácido Láctico , Osseointegração , Ácido Poliglicólico , Polímeros , Próteses e Implantes , Crânio/cirurgia , Animais , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos
10.
Mil Med ; 161(1): 37-42, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11082750

RESUMO

In this study an all-male population of 256 U.S. Army basic trainees and 98 armor officer basic course students were surveyed concerning extent of use, knowledge of, and factors contributing to the use of smokeless tobacco (ST). The survey was administered at a dental clinic at Fort Knox, Kentucky. The data were analyzed using the SPSS computer software program. Results showed that more than 17% of this population were either occasional or regular users of ST. Nearly 24% had tried ST and more than 9% were former users. Exactly one-half had not tried ST. A typical user was white, had started ST use at age 14, had used it for 4 years, and was most likely to use snuff or dip. Higher educational level achieved was associated with increased likelihood of ST use. Nearly 22% of college graduates used ST, whereas only 15.3% of high school graduates or those with some college were users. Knowledge about the potential health effects of ST was generally high or moderately high, except for its ability to cause hypertension. This was true for both high school and college graduates, although college graduates were somewhat more informed. Few in this population had a personal attitude of approval toward ST use, and very few perceived that either their parents or their superiors in the military approved of ST use. Perceived attitude of approval was highest from friends and peers. The principle reasons for starting ST use were use by friends and curiosity about taste and effects. Influence from public figures, such as athletes, and from advertising was minimal. Enjoyment of flavor and taste was found to be the main reason for continued ST use. Health professionals were identified by the majority of respondents as the single most important information source on ST. Relatively few (27%), however, stated that their dentist or hygienist had ever discussed ST with them.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Militares , Plantas Tóxicas , Tabagismo/epidemiologia , Tabagismo/psicologia , Tabaco sem Fumaça , Adolescente , Adulto , Atitude Frente a Saúde , Escolaridade , Humanos , Kentucky/epidemiologia , Masculino , Medicina Militar , Militares/educação , Militares/psicologia , Grupo Associado , Prevalência , Inquéritos e Questionários , Tabaco sem Fumaça/efeitos adversos
11.
Gen Dent ; 45(2): 172-6, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9515405

RESUMO

Odontogenic keratocysts comprise approximately eight percent of all jaw cysts and have a significant recurrence rate. Following a review of the literature, the treatment of two patients with such cysts is described.


Assuntos
Doenças Mandibulares/cirurgia , Cistos Odontogênicos/cirurgia , Adolescente , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Doenças Mandibulares/patologia , Cistos Odontogênicos/patologia , Radiografia Panorâmica , Recidiva , Tomografia Computadorizada por Raios X
12.
Gen Dent ; 44(6): 538-43, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9515396

RESUMO

In a survey of military dentists to examine use of antimicrobial agents in the management of third molars, questions addressed use of antibiotics and an antimicrobial rinse in treating pericoronitis and third molar extractions. Results were compared with information from a literature review. According to the survey, a majority of clinicians use antibiotics to treat pericoronitis but not surgical extraction of asymptomatic dental impactions. About 60 percent of respondents use a preoperative rinse with chlorhexidine in treating the third molar conditions discussed. A postoperative rinse with chlorhexidine was used less frequently. Half the respondents listed medicolegal factors in their decisions.


Assuntos
Antibioticoprofilaxia/estatística & dados numéricos , Dente Serotino/cirurgia , Padrões de Prática Odontológica/estatística & dados numéricos , Extração Dentária , Anti-Infecciosos Locais/uso terapêutico , Alvéolo Seco/prevenção & controle , Humanos , Odontologia Militar , Pericoronite/tratamento farmacológico , Infecção da Ferida Cirúrgica/prevenção & controle , Inquéritos e Questionários , Estados Unidos
13.
Ulster Med J ; 63(2): 155-61, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8650828

RESUMO

Deliberate self-poisoning presenting at Craigavon Area Hospital in 1991 was examined and compared to the years 1976 and 1986. Self-poisoning has not declined over the 15 year period 1976-1991. The reduction in the use of benzodiazepines, and increase in paracetamol, previously reported, continues. Possible reasons for this are examined, in relation to local and national drug prescribing.


Assuntos
Overdose de Drogas/epidemiologia , Tentativa de Suicídio/tendências , Acetaminofen/intoxicação , Adolescente , Adulto , Analgésicos não Narcóticos/intoxicação , Benzodiazepinas/intoxicação , Criança , Feminino , Humanos , Masculino , Irlanda do Norte/epidemiologia , Estudos Retrospectivos , Tentativa de Suicídio/estatística & dados numéricos
15.
Plasmid ; 17(1): 54-7, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3107003

RESUMO

Plasmid pPR328 has been constructed for use as a chloramphenicol-resistant, intermediate cloning vector when manipulating DNA fragments cloned in vectors of the pUC family. The method used in its construction may be of general use for the replacement of the ampicillin resistance marker of pBR322-based plasmids with other drug resistance cassettes.


Assuntos
Cloranfenicol , Clonagem Molecular/métodos , Vetores Genéticos , DNA Bacteriano/genética , Fatores R , beta-Galactosidase/genética
16.
Mol Microbiol ; 9(4): 787-801, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8231810

RESUMO

The syrD gene of Pseudomonas syringae pathovar syringae strain B301D-R was characterized and sequenced. The syrD open reading frame is 1695 bp long and encodes a predicted protein, SyrD, of approximately 63 kDa. Database searches revealed that SyrD shares a high degree of similarity with the ATP-binding cassette (ABC) superfamily of transporter proteins which are responsible for specific nutrient uptake and for secretion of certain cellular products in prokaryotes, and for multiple drug resistance in mammals. The amino acid sequence homology between SyrD and the ABC proteins was greatest at the conserved residues which constitute the ATP-binding cassette of these proteins; these residues lie in the hydrophilic C-terminal half of SyrD. The N-terminus of SyrD is predicted to be hydrophobic and to contain six membrane-spanning alpha-helices. syrD mutants of strain B301D-R were significantly less virulent than other syr mutants, were deficient in four large polypeptides thought to be components of a syringomycin synthetase complex, and showed reduced expression of a syrB-lacZ reporter gene fusion in trans. It is proposed that SyrD is a cytoplasmic membrane protein that functions as an ATP-driven efflux pump for the secretion of syringomycin.


Assuntos
Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Proteínas de Transporte/genética , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Família Multigênica , Pseudomonas/genética , Transportadores de Cassetes de Ligação de ATP , Trifosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/metabolismo , Sequência de Bases , Sítios de Ligação , Proteínas de Transporte/metabolismo , Sequência Consenso , Dados de Sequência Molecular , Mutagênese Insercional , Fases de Leitura Aberta , Doenças das Plantas/microbiologia , Pseudomonas/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Virulência
17.
J Bacteriol ; 177(14): 4009-20, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7608074

RESUMO

The syrB and syrC genes are required for synthesis of syringomycin, a lipodepsipeptide phytotoxin produced by Pseudomonas syringae pv. syringae, and are induced by plant-derived signal molecules. A 4,842-bp chromosomal region containing the syrB and syrC genes of strain B301D was sequenced and characterized. The open reading frame (ORF) of syrB was 2,847 bp in length and was predicted to encode an approximately 105-kDa protein, SyrB, with 949 amino acids. Searches of databases revealed that SyrB shares homology with members of a superfamily of adenylate-forming enzymes involved in peptide antibiotic and siderophore synthesis in a diverse spectrum of microorganisms. SyrB exhibited the highest degree of overall similarity (56.4%) and identity (33.8%) with the first amino acid-activating domain of pyoverdin synthetase, PvdD, of Pseudomonas aeruginosa. The N-terminal portion of SyrB contained a domain of approximately 600 amino acids that resembles the amino acid-activating domains of thiotemplate-employing peptide synthetases. The SyrB domain contained six signature core sequences with the same order and spacing as observed in all known amino acid-activating domains involved in nonribosomal peptide synthesis. Core sequence 6 of SyrB, for example, was similar to the binding site for 4'-phosphopantetheine, a cofactor required for thioester formation. The syrC ORF (1,299 bp) was located 175 bp downstream of the syrB ORF. Analysis of the transcriptional and translational relationship between the syrB and syrC genes demonstrated that they are expressed independently. The syrC ORF was predicted to encode an approximately 48-kDa protein product of 433 amino acids which is 42 to 48% similar to a number of thioesterases, including fatty acid thioesterases, haloperoxidases, and acyltransferases, that contain a characteristic GXS (C) XG motif. In addition, a zinc-binding motif was found near the C terminus of SyrC. The data suggest that SyrB and SyrC function as peptide synthetases in a thiotemplate mechanism of syringomycin biosynthesis.


Assuntos
Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Genes Bacterianos/genética , Pseudomonas/genética , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação/genética , Expressão Gênica , Dados de Sequência Molecular , Peptídeo Sintases/genética , Filogenia , Biossíntese de Proteínas , Pseudomonas/enzimologia , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Tioléster Hidrolases/genética , Transcrição Gênica
18.
Appl Environ Microbiol ; 63(7): 2771-8, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9212424

RESUMO

Syringomycin is a lipodepsinonapeptide phytotoxin synthesized by Pseudomonas syringae pv. syringae on multienzymatic peptide synthetases. Sequence analysis of the interval between the syrB and syrD genes of P. syringae pv. syringae strain B301D revealed a 1,059-bp open reading frame (ORF), designated syrP. The predicted product of this ORF was a 39.6-kDa protein consisting of 353 amino acid residues. Searches of protein sequence databases demonstrated that SyrP was most similar to histidine kinases such as the CheA regulatory protein of Escherichia coli. The predicted SyrP sequence was aligned with the N terminus of CheA, a region corresponding to the phosphotransfer and acceptor domains of CheA. The SyrP region that aligns with the phosphotransfer domain of CheA contained a His at position 101 which is flanked by a weak consensus sequence of the unorthodox sensory kinase subfamily of two-component regulatory systems. Strain B301D-31, obtained by site-directed insertional mutagenesis of the syrP gene, exhibited an unusual pleiotropic phenotype including a failure to produce syringomycin in liquid media in contrast to production of elevated levels of the toxin on agar media. The syrP mutant was relieved of the suppression of toxin production that accompanies inorganic phosphate concentrations of > 1 mM on agar media. Nevertheless, the syrP mutant was substantially less virulent than the wild-type strain in pathogenicity assays in cherry fruits. These results suggest that the syrP gene encodes a regulatory protein that participates in a phosphorylation cascade controlling syringomycin production and virulence in P. syringae pv. syringae.


Assuntos
Proteínas de Bactérias/genética , Peptídeo Sintases , Pseudomonas/genética , Transportadores de Cassetes de Ligação de ATP , Sequência de Aminoácidos , Proteínas de Bactérias/metabolismo , Sequência de Bases , Proteínas de Transporte/genética , Mapeamento Cromossômico , Escherichia coli/genética , Proteínas de Escherichia coli , Frutas/microbiologia , Regulação Bacteriana da Expressão Gênica , Teste de Complementação Genética , Histidina/genética , Histidina Quinase , Proteínas de Membrana/genética , Proteínas Quimiotáticas Aceptoras de Metil , Dados de Sequência Molecular , Mutagênese Insercional , Fases de Leitura Aberta , Proteínas Quinases/genética , Pseudomonas/patogenicidade , Recombinação Genética , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Virulência/genética
19.
Mol Gen Genet ; 203(1): 172-6, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2423848

RESUMO

The rfb gene cluster of Salmonella typhimurium encodes the enzymes required for the biosynthesis of the O-Antigen. A part of it has been cloned in plasmid vectors pBR322 and pUC9 using an adjacent, previously cloned, part of the his operon (Barnes 1981) as a molecular probe for the first clone. A detailed restriction enzyme map of 7.57 kb of rfb DNA is presented and the approximate locations of two of the genes, rfbK and rfbM have been defined.


Assuntos
Antígenos de Bactérias/genética , Antígenos de Superfície/genética , Clonagem Molecular , Genes Bacterianos , Genes , Lipopolissacarídeos/genética , Salmonella typhimurium/genética , Enzimas de Restrição do DNA , Vetores Genéticos , Antígenos O , Plasmídeos , Salmonella typhimurium/imunologia
20.
J Bacteriol ; 170(1): 103-7, 1988 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2447059

RESUMO

The O antigens of Salmonella serogroups A, B, and D differ structurally in their side-chain sugar residue. These genes encoding O-antigen biosynthesis are clustered in the rfb operon. We report here the molecular cloning and analysis of the rfb operons of Salmonella paratyphi A (serogroup A) and S. typhi (serogroup D). The regions of DNA nonhomology between the rfb operons of these serogroup A, B, and D representatives are identified, and the evolutionary derivation of serogroup A from a serogroup D progenitor is discussed.


Assuntos
Antígenos de Bactérias/genética , Genes Bacterianos , Óperon , Salmonella/genética , Variação Antigênica , Mapeamento Cromossômico , Clonagem Molecular , Cosmídeos , Enzimas de Restrição do DNA , DNA Bacteriano/genética , DNA Bacteriano/ultraestrutura , Microscopia Eletrônica , Hibridização de Ácido Nucleico , Antígenos O , Salmonella/imunologia , Salmonella paratyphi A/genética , Salmonella paratyphi A/imunologia , Salmonella typhi/genética , Salmonella typhi/imunologia , Salmonella typhimurium/genética , Salmonella typhimurium/imunologia , Homologia de Sequência do Ácido Nucleico
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