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1.
Public Health ; 168: 164-167, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30772009

RESUMO

OBJECTIVES: This study aimed to understand what information the US media communicated about Zika virus (ZIKV) and travel in 2016 and 2017. STUDY DESIGN: We conducted a content analysis of news coverage about ZIKV and travel from April 5, 2016 to March 31, 2017. METHODS: We obtained a stratified, random sample of English language, US print newspaper and television news coverage about ZIKV and travel. We developed a coding scheme to assess key messages in the news, including how ZIKV is transmitted, the symptoms and outcomes of ZIKV infection, and recommended prevention behaviors. RESULTS: Almost all news stories mentioned mosquito-borne transmission (96.8%) and just over half mentioned sexual transmission (55.3%). News stories were more likely to talk about ZIKV outcomes (78.8%) than ZIKV symptoms (40.6%). However, outcomes affecting babies were mentioned more frequently than outcomes affecting adults. Recommendations included a wide array of protective behaviors, such as delaying or avoiding travel (77.6%) and using mosquito repellent (41.0%). However, few studies (10.9%) mentioned barriers to practicing ZIKV prevention behaviors. CONCLUSIONS: Public health organizations and professionals can use these findings to help improve communication about future outbreaks of mosquito-borne illnesses. We also recommend conducting real-time monitoring of news media and frequent content analysis of news stories to ensure coverage provides the information the public needs.


Assuntos
Surtos de Doenças , Meios de Comunicação de Massa/estatística & dados numéricos , Viagem , Infecção por Zika virus/epidemiologia , Humanos , Estados Unidos/epidemiologia
2.
J Dent Res ; 97(10): 1106-1113, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29928831

RESUMO

Periodontal disease (PD) shares common risk factors with cardiovascular disease. Our hypothesis was that having a family history of myocardial infarction (FamHxMI) may be a novel risk factor for PD. Risk assessment based on FamHxMI, conditional on smoking status, was examined given the strong influence of smoking on PD. Exploratory analysis with inflammatory biomarkers and genetic determinants was conducted to understand potential mechanistic links. The Women's Genome Health Study (WGHS) is a prospective cohort of US female health care professionals who provided blood samples at baseline in the Women's Health Study, a 2 × 2 factorial clinical trial investigating vitamin E and aspirin in the prevention of cardiovascular disease and cancer. PD was ascertained via self-report over 12 y of follow-up. Prevalence (3,442 cases), incidence (1,365 cases), and survival analysis of PD were investigated for associations of FamHxMI as well as in strata of FamHxMI by smoking. Kruskal-Wallis, chi-square tests, multivariate regression, and Cox proportional hazard models were used for the analyses. In the WGHS, women with FamHxMI showed higher risk of ever having PD. A particularly high-risk group of having both FamHxMI and smoking at baseline was highlighted in the prevalence and risk of developing PD. PD risk increased according to the following strata: no FamHxMI and nonsmokers (reference), FamHxMI and nonsmokers (hazard ratio [HR] = 1.2, 95% CI = 1.0 to 1.5), smokers without FamHxMI (HR = 1.3, 95% CI = 1.2 to 1.5), and smokers with FamHxMI (HR = 1.5, 95% CI = 1.2 to 1.8). An independent analysis by the dental Atherosclerosis Risk in Communities study ( N = 5,552) identified more severe periodontitis cases among participants in the high-risk group (smokers with FamHxMI). Further examination of interactions among inflammatory biomarkers or genetic exploration with FamHxMI did not explain the risk increase of PD associated with FamHxMI in the WGHS. Future efforts based on an integrative-omics approach may facilitate validation of these findings and suggest a mechanistic link between PD and FamHxMI.


Assuntos
Anamnese , Infarto do Miocárdio/complicações , Doenças Periodontais/etiologia , Fumar/efeitos adversos , Feminino , Humanos , Incidência , Anamnese/estatística & dados numéricos , Pessoa de Meia-Idade , Infarto do Miocárdio/genética , Doenças Periodontais/epidemiologia , Doenças Periodontais/genética , Prevalência , Fatores de Risco
4.
HLA ; 91(2): 127-128, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29168355

RESUMO

HLA-A*26:01:44 differs from HLA-A*26:01:01 by a single substitution in exon 5.


Assuntos
Alelos , Antígenos HLA-A/genética , População Branca/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos
6.
HLA ; 90(3): 182-183, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28660703

RESUMO

HLA-DQB1*05:144 differs from HLA-DQB1*05:01:01 by a single substitution in exon 3.


Assuntos
Alelos , Cadeias beta de HLA-DQ/genética , Transplante de Células-Tronco , Doadores de Tecidos , Sudeste Asiático , Humanos
7.
Haemophilia ; 23(2): 198-206, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28124511

RESUMO

INTRODUCTION: Chronic hepatitis C virus (HCV) infection is prevalent among patients with inherited bleeding disorders and is a leading cause of mortality in those with haemophilia. AIM: We evaluated the efficacy and safety of ledipasvir-sofosbuvir and sofosbuvir plus ribavirin in patients with chronic HCV genotype 1-4 infection and an inherited bleeding disorder. METHODS: Ledipasvir-sofosbuvir was administered for 12 weeks to patients with genotype 1 or 4 infection and for 12 or 24 weeks to treatment-experienced cirrhotic patients with genotype 1 infection. Patients with genotype 2 and 3 infection received sofosbuvir plus ribavirin for 12 and 24 weeks respectively. RESULTS: The majority of the 120 treated patients had a severe bleeding disorder (55%); overall, 65% of patients had haemophilia A and 26% of patients had haemophilia B; 22% were HIV coinfected. Sustained virologic response at 12 weeks posttreatment was 99% (98/99) in patients with genotype 1 or 4 infection; 100% (5/5) in treatment-experienced cirrhotic patients with genotype 1 infection; 100% (10/10) in patients with genotype 2 infection; and 83% (5/6) in patients with genotype 3 infection. There were no treatment discontinuations due to adverse events (AEs). The most frequent non-bleeding AEs were fatigue, headache, diarrhoea, nausea and insomnia. Bleeding AEs occurred in 22 patients, of which all but one were considered unrelated to treatment. CONCLUSION: Treatment with ledipasvir-sofosbuvir for patients with HCV genotype 1 or 4 infection or sofosbuvir plus ribavirin for patients with genotype 2 or 3 infection was highly effective and well tolerated among those with inherited bleeding disorders.


Assuntos
Antivirais/uso terapêutico , Benzimidazóis/uso terapêutico , Fluorenos/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Ribavirina/uso terapêutico , Sofosbuvir/uso terapêutico , Adulto , Idoso , Antivirais/administração & dosagem , Benzimidazóis/administração & dosagem , Combinação de Medicamentos , Feminino , Fluorenos/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Ribavirina/administração & dosagem , Sofosbuvir/administração & dosagem , Resultado do Tratamento , Adulto Jovem
8.
HLA ; 89(1): 56-57, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27863124

RESUMO

HLA-B*18:124 differs from B*18:01:01:02 by a single substitution in exon 4.

10.
J Viral Hepat ; 23(8): 614-22, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26957110

RESUMO

GS-9857, an inhibitor of the hepatitis C virus (HCV) nonstructural protein (NS) 3/4A, demonstrates potent activity against HCV genotypes 1-6 and improved coverage against commonly encountered NS3 resistance-associated variants (RAVs). In this study, the safety, tolerability, antiviral activity and pharmacokinetics (PK) of GS-9857 were evaluated in patients with chronic HCV genotype 1-4 infection. Patients with genotype 1-4 infection received placebo or once-daily GS-9857 at doses ranging from 50 to 300 mg for 3 days under fasting conditions. GS-9857 was well tolerated; all reported adverse events (AEs) were mild or moderate in severity. Diarrhoea and headache were the most commonly reported AEs. Grade 3 or 4 laboratory abnormalities were observed in 17% of patients receiving GS-9857; there were no Grade 3 or 4 abnormalities in alanine aminotransferase, aspartate aminotransferase or alkaline phosphatase levels. GS-9857 demonstrated potent antiviral activity in patients with chronic HCV infection, achieving mean and median maximum reductions in HCV RNA of ≥3 log10 IU/mL following administration of a 100-mg dose in patients with HCV genotype 1a, 1b, 2, 3 or 4 infection. The antiviral activity of GS-9857 was unaffected by the presence of pretreatment NS3 RAVs. In patients with genotype 1-4 infection, GS-9857 exhibited linear PK and was associated with a median half-life of 29-42 h, supporting once-daily dosing. Thus, the tolerability, efficacy and pharmacokinetic profile of GS-9857 support its further evaluation for treatment of patients with chronic HCV infection.


Assuntos
Antivirais/administração & dosagem , Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Compostos Macrocíclicos/administração & dosagem , Sulfonamidas/administração & dosagem , Adolescente , Adulto , Idoso , Ácidos Aminoisobutíricos , Antivirais/efeitos adversos , Antivirais/farmacocinética , Antivirais/farmacologia , Ciclopropanos , Método Duplo-Cego , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Hepacivirus/isolamento & purificação , Humanos , Lactamas Macrocíclicas , Leucina/análogos & derivados , Compostos Macrocíclicos/efeitos adversos , Compostos Macrocíclicos/farmacocinética , Compostos Macrocíclicos/farmacologia , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Prolina/análogos & derivados , Quinoxalinas , Sulfonamidas/efeitos adversos , Sulfonamidas/farmacocinética , Sulfonamidas/farmacologia , Resultado do Tratamento , Carga Viral , Adulto Jovem
11.
J Viral Hepat ; 22(12): 977-82, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26280786

RESUMO

The interaction of lipoproteins with hepatitis C virus (HCV) has pathogenic and therapeutic implications. Our aim was to evaluate changes in the apolipoprotein profile of patients with chronic hepatitis C during and after successful cure with ledipasvir and sofosbuvir (LDV/SOF) with and without ribavirin (RBV). One hundred HCV genotype 1 patients who had achieved SVR-12 after treatment with 12 weeks of LDV/SOF ± RBV were selected from the ION-1 clinical trial. Frozen serum samples from baseline, end of treatment and week 4 of follow-up were used to assay apolipoproteins (apoAI, apoAII, apoB, apoCII, apoCIII, apoE) using the Multiplex platform to assess for changes in the apolipoprotein levels. At the end of treatment compared to baseline, a significant reduction in apoAII levels (-14.97 ± 63.44 µg/mL, P = 0.0067) and apoE levels (-4.38 ± 12.19 µg/mL, P < 0.001) was noted. These declines from baseline in apoAII (-16.59 ±66.15 µg/mL, P = 0.0075) and apoE (-2.66 ± 12.64 µg/mL, P = 0.015) persisted at 4 weeks of post-treatment follow-up. In multivariate analysis, treatment with LDV/SOF + RBV was independently associated with reduction in apoE (beta = 5.31 µg/mL, P = 0.002) (compared to RBV-free LDV/SOF) (P < 0.05). In contrast, apoCII levels overall increased from baseline to end of treatment (+2.74 ±11.76 µg/mL, P = 0.03) and persisted at 4 weeks of follow-up (+4.46 ± 12.81 µg/mL from baseline, P = 0.0005). Subgroup analysis revealed an increase in apoCII during treatment only in patients receiving LDV/SOF without RBV (+5.52 ± 11.92 µg/mL, P = 0.0007) but not in patients receiving LDV/SOF + RBV (P = 0.638). Treatment with LDV/SOF ± RBV is associated with a persistent reduction in the apolipoprotein AII and E after achieving cure. These data suggest that treatment with LDV/SOF ± RBV may be associated with alterations in serum apolipoproteins which could potentially impact viral eradication.


Assuntos
Antivirais/uso terapêutico , Apolipoproteínas/sangue , Benzimidazóis/uso terapêutico , Fluorenos/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Sofosbuvir/uso terapêutico , Quimioterapia Combinada , Feminino , Hepacivirus/efeitos dos fármacos , Hepacivirus/metabolismo , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Ribavirina/uso terapêutico
12.
Tissue Antigens ; 85(2): 142-4, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25626609

RESUMO

The novel allele, HLA-B*27:131, was identified and full genomic DNA was successfully cloned.


Assuntos
Alelos , Antígenos HLA-B/genética , Sequência de Bases , Humanos , Dados de Sequência Molecular , Alinhamento de Sequência
13.
Epidemiol Infect ; 143(8): 1567-74, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25358292

RESUMO

Syphilis is a chronic, multi-stage infectious disease that is usually transmitted sexually by contact with an active lesion of a partner or congenitally from an infected pregnant woman to her fetus. Although syphilis is still endemic in many developing countries, it has re-emerged in several developed countries. The resurgence of syphilis is a major concern to global public health, particularly since the lesions of early syphilis increase the risk of acquisition and transmission of infection with human immunodeficiency virus (HIV). Because there is no vaccine to prevent syphilis, control is mainly dependent on the identification and treatment of infected individuals and their contacts with penicillin G, the first-line drug for all stages of syphilis. The emergence of clinically significant azithromycin resistance in Treponema pallidum subsp. pallidum, the syphilis agent, has resulted in treatment failures, thus precluding the routine use of this second-line drug. Information is presented here on the diagnosis and recommended antibiotic treatment of syphilis and the challenge of macrolide-resistant T. pallidum.


Assuntos
Antibacterianos/uso terapêutico , Azitromicina/uso terapêutico , Farmacorresistência Bacteriana , Penicilina G/uso terapêutico , Sífilis/tratamento farmacológico , Coinfecção , Feminino , Infecções por HIV/complicações , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Masculino , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Sífilis/complicações , Sífilis Congênita/tratamento farmacológico , Treponema pallidum
14.
J Periodontal Res ; 50(1): 52-61, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24690098

RESUMO

BACKGROUND AND OBJECTIVE: Genetic markers associated with disease are often non-functional and generally tag one or more functional "causative" variants in linkage disequilibrium. Markers may not show tight linkage to the causative variants across multiple ethnicities due to evolutionary divergence, and therefore may not be informative across different population groups. Validated markers of disease suggest causative variants exist in the gene and, if the causative variants can be identified, it is reasonable to hypothesize that such variants will be informative across diverse populations. The aim of this study was to test that hypothesis using functional Interleukin-1 (IL-1) gene variations across multiple ethnic populations to replace the non-functional markers originally associated with chronic adult periodontitis in Caucasians. MATERIAL AND METHODS: Adult chronic periodontitis cases and controls from four ethnic groups (Caucasians, African Americans, Hispanics and Asians) were recruited in the USA, Chile and China. Genotypes of IL1B gene single nucleotide polymorphisms (SNPs), including three functional SNPs (rs16944, rs1143623, rs4848306) in the promoter and one intronic SNP (rs1143633), were determined using a single base extension method or TaqMan 5' nuclease assay. Logistic regression and other statistical analyses were used to examine the association between moderate to severe periodontitis and IL1B gene variations, including SNPs, haplotypes and composite genotypes. Genotype patterns associated with disease in the discovery study were then evaluated in independent validation studies. RESULTS: Significant associations were identified in the discovery study, consisting of Caucasians and African Americans, between moderate to severe adult chronic periodontitis and functional variations in the IL1B gene, including a pattern of four IL1B SNPs (OR = 1.87, p < 0.0001). The association between the disease and this IL1B composite genotype pattern was validated in two additional studies consisting of Hispanics (OR = 1.95, p = 0.04) or Asians (OR = 3.27, p = 0.01). A meta-analysis of the three populations supported the association between the IL-1 genotype pattern and moderate to severe periodontitis (OR 1.95; p < 0.001). Our analysis also demonstrated that IL1B gene variations had added value to conventional risk factors in predicting chronic periodontitis. CONCLUSION: This study validated the influence of IL-1 genetic factors on the severity of chronic periodontitis in four different ethnicities.


Assuntos
Periodontite Crônica/imunologia , Etnicidade/genética , Variação Genética/genética , Interleucina-1beta/genética , Adulto , Negro ou Afro-Americano/genética , Idoso , Povo Asiático/genética , Estudos de Casos e Controles , Chile/etnologia , China/etnologia , Periodontite Crônica/genética , Estudos de Coortes , Feminino , Genótipo , Haplótipos/genética , Hispânico ou Latino/genética , Humanos , Indígenas Sul-Americanos/genética , Íntrons/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética , Estados Unidos/etnologia , População Branca/genética
15.
J Dent Res ; 92(8): 694-701, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23752171

RESUMO

Prevention reduces tooth loss, but little evidence supports biannual preventive care for all adults. We used risk-based approaches to test tooth loss association with 1 vs. 2 annual preventive visits in high-risk (HiR) and low-risk (LoR) patients. Insurance claims for 16 years for 5,117 adults were evaluated retrospectively for tooth extraction events. Patients were classified as HiR for progressive periodontitis if they had ≥ 1 of the risk factors (RFs) smoking, diabetes, interleukin-1 genotype; or as LoR if no RFs. LoR event rates were 13.8% and 16.4% for 2 or 1 annual preventive visits (absolute risk reduction, 2.6%; 95%CI, 0.5% to 5.8%; p = .092). HiR event rates were 16.9% and 22.1% for 2 and 1 preventive visits (absolute risk reduction, 5.2%; 95%CI, 1.8% to 8.4%; p = .002). Increasing RFs increased events (p < .001). Oral health care costs were not increased by any single RF, regardless of prevention frequency (p > .41), but multiple RFs increased costs vs. no (p < .001) or 1 RF (p = .001). For LoR individuals, the association between preventive dental visits and tooth loss was not significantly different whether the frequency was once or twice annually. A personalized medicine approach combining gene biomarkers with conventional risk factors to stratify populations may be useful in resource allocation for preventive dentistry (ClinicalTrials.gov, NCT01584479).


Assuntos
Agendamento de Consultas , Assistência Odontológica/estatística & dados numéricos , Perda de Dente/prevenção & controle , Adulto , Doença Crônica , Estudos de Coortes , Assistência Odontológica/economia , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 2/epidemiologia , Suscetibilidade a Doenças , Feminino , Genótipo , Custos de Cuidados de Saúde/estatística & dados numéricos , Humanos , Seguro Odontológico/estatística & dados numéricos , Interleucina-1/genética , Masculino , Michigan/epidemiologia , Pessoa de Meia-Idade , Periodontite/epidemiologia , Odontologia Preventiva/estatística & dados numéricos , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fumar/epidemiologia , Extração Dentária/estatística & dados numéricos , Perda de Dente/epidemiologia
16.
Vet Microbiol ; 136(1-2): 192-6, 2009 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-19059737

RESUMO

The etiology of bovine ulcerative mammary dermatitis (UMD) is poorly characterized. The goal of this study was to genetically analyze spirochetes present in UMD lesions. DNA prepared from UMD lesion biopsies and from spirochetes cultured from the corresponding lesion biopsies was PCR amplified using primers for the 16S rDNA-tRNA(ile) intergenic spacer region (ISR) of Treponema 16S-23S rDNA. Analysis of cloned ISR amplicons from three cultivable UMD-associated spirochetes indicated that two isolates cluster closely with cultivable papillomatous digital dermatitis (PDD)-associated and human-associated Treponema phylotypes, while the remaining isolate is unique. Analysis of ISR amplicons from UMD lesion biopsies identified additional not-yet-cultivable Treponema phylotypes. Our results revealed the presence of a genetically diverse Treponema population in an UMD lesion.


Assuntos
Doenças Mamárias/veterinária , Doenças dos Bovinos/microbiologia , Dermatite/veterinária , Treponema/genética , Infecções por Treponema/veterinária , Animais , Sequência de Bases , Biópsia/veterinária , Doenças Mamárias/microbiologia , Bovinos , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Dermatite/microbiologia , Feminino , Variação Genética , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase/veterinária , Alinhamento de Sequência , Infecções por Treponema/microbiologia
17.
Tissue Antigens ; 72(5): 492-4, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18937794

RESUMO

A new HLA-B allele (B*4093) in a North Indian Hindu donor differing from B*4006 by four nucleotide substitutions in codon 41.1, codon 44.3, codon 45.1 and codon 50.3 has been identified. This novel allele was part of the A*0211-B*4093-Cw*1502-DRB1*15-DQB1*06 HLA haplotype.


Assuntos
Alelos , Antígenos HLA-B/genética , Haplótipos , Sequência de Bases , Humanos , Dados de Sequência Molecular , Alinhamento de Sequência
18.
Clin Exp Obstet Gynecol ; 31(2): 143-6, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15266773

RESUMO

The medical and psychological treatment for a 37-year-old Caucasian G6 P1051 woman who presented for evaluation of secondary infertility and recurrent pregnancy loss is described. Although one living child had been conceived without medical assistance, that delivery preceded the present evaluation by ten years and involved a different partner. With the current husband, the patient had two miscarriages and a left ectopic pregnancy. The couple had attempted controlled ovarian hyperstimulation and in vitro fertilization (IVF) elsewhere, but the cycle was cancelled due to poor follicular response. About one year before consultation at our institution, the couple established a pregnancy although the infant was born at 24 weeks with a cardiac anomaly, living only 40 days. Additionally, a persistent cervical lesion required cone biopsy before any fertility treatment could resume. Andrology evaluation found the husband's sperm DNA fragmentation index to be 48.6%. This constellation of stressors represented substantial emotional issues and psychological therapy/counseling was recommended. After obtaining psychological clearance, the couple underwent IVF and 16 oocytes were retrieved. Four embryos were transferred, and a healthy male infant was delivered at term. Although multifactorial infertility can be associated with very poor reproductive outcomes, the advanced reproductive technologies merit consideration during management of complex clinical challenges. Standard IVF strategies can be optimized by inclusion of thorough psychological assessment and counseling.


Assuntos
Aborto Habitual/psicologia , Terapia Comportamental , Fertilização in vitro , Adulto , Feminino , Humanos , Lactente , Recém-Nascido , Infertilidade/psicologia , Masculino , Gravidez , Gravidez Ectópica/psicologia
19.
J Clin Microbiol ; 40(9): 3463-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12202594

RESUMO

Papillomatous digital dermatitis (PDD), an emerging infectious disease of cattle, is characterized by painful, ulcerative foot lesions. The detection of high numbers of invasive spirochetes in PDD lesions suggests an important role for these organisms in the pathogenesis of PDD. PDD-associated spirochetes have phenotypic characteristics consistent with members of the genus TREPONEMA: Partial 16S ribosomal DNA (rDNA) sequence analysis of clonal isolates from California cattle showed that they comprise three phylotypes which cluster closely with human-associated Treponema spp. of the oral cavity (T. denticola and T. medium/T. vincentii) or genital area (T. phagedenis). The goal of our study was to apply 16S-23S rDNA intergenic spacer region (ISR) sequence analysis to the molecular typing of U.S. PDD-associated Treponema isolates. This methodology has potentially greater discriminatory power for differentiation of closely related bacteria than 16S rDNA analysis. We PCR amplified, cloned, and sequenced the ISRs from six California PDD-associated Treponema isolates and, for comparative purposes, one strain each of T. denticola, T. medium, T. vincentii, and T. phagedenis. Two ISRs that varied in length and composition were present in all the PDD-associated Treponema isolates and in T. denticola, T. medium, and T. phagedenis. ISR1 contained a tRNA(Ala) gene, while ISR2 contained a tRNA(Ile) gene. Only a single ISR (ISR1) was identified in T. vincentii. Comparative analyses of the ISR1 and ISR2 sequences indicated that the California PDD-associated Treponema isolates comprised three phylotypes, in agreement with the results of 16S rDNA analysis. PCR amplification of the 16S-tRNA(Ile) region of ISR2 permitted rapid phylotyping of California and Iowa PDD-associated Treponema isolates based on product length polymorphisms.


Assuntos
Doenças dos Bovinos/microbiologia , DNA Espaçador Ribossômico/análise , Dermatite/veterinária , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , Treponema/classificação , Animais , Técnicas de Tipagem Bacteriana , Sequência de Bases , California , Bovinos , Dermatite/microbiologia , Humanos , Iowa , Dados de Sequência Molecular , Análise de Sequência de DNA , Treponema/genética , Infecções por Treponema/microbiologia , Infecções por Treponema/veterinária
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