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1.
mSphere ; 3(6)2018 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-30404935

RESUMO

Enterococcus faecium has a highly variable genome prone to recombination and horizontal gene transfer. Here, we have identified a novel genetic island with an insertion locus and mobilization genes similar to those of staphylococcus cassette chromosome elements SCCmec This novel element termed the enterococcus cassette chromosome (ECC) element was located in the 3' region of rlmH and encoded large serine recombinases ccrAB similar to SCCmec Horizontal transfer of an ECC element termed ECC::cat containing a knock-in cat chloramphenicol resistance determinant occurred in the presence of a conjugative reppLG1 plasmid. We determined the ECC::cat insertion site in the 3' region of rlmH in the E. faecium recipient by long-read sequencing. ECC::cat also mobilized by homologous recombination through sequence identity between flanking insertion sequence (IS) elements in ECC::cat and the conjugative plasmid. The ccrABEnt genes were found in 69 of 516 E. faecium genomes in GenBank. Full-length ECC elements were retrieved from 32 of these genomes. ECCs were flanked by attR and attL sites of approximately 50 bp. The attECC sequences were found by PCR and sequencing of circularized ECCs in three strains. The genes in ECCs contained an amalgam of common and rare E. faecium genes. Taken together, our data imply that ECC elements act as hot spots for genetic exchange and contribute to the large variation of accessory genes found in E. faeciumIMPORTANCEEnterococcus faecium is a bacterium found in a great variety of environments, ranging from the clinic as a nosocomial pathogen to natural habitats such as mammalian intestines, water, and soil. They are known to exchange genetic material through horizontal gene transfer and recombination, leading to great variability of accessory genes and aiding environmental adaptation. Identifying mobile genetic elements causing sequence variation is important to understand how genetic content variation occurs. Here, a novel genetic island, the enterococcus cassette chromosome, is shown to contain a wealth of genes, which may aid E. faecium in adapting to new environments. The transmission mechanism involves the only two conserved genes within ECC, ccrABEnt, large serine recombinases that insert ECC into the host genome similarly to SCC elements found in staphylococci.


Assuntos
Cromossomos Bacterianos , Enterococcus faecium/genética , Transferência Genética Horizontal , Ilhas Genômicas , Recombinação Genética , Conjugação Genética , Elementos de DNA Transponíveis , Plasmídeos , Análise de Sequência de DNA
2.
Indian J Pharm Sci ; 78(1): 34-40, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27168679

RESUMO

Methanol extracts of seven edible fruits found in southern Brazil: Garcinia achachairu, Rubus imperialis, Rubus rosaefolius, Solanum quitoense, Solanum sessiliflorun, Diospyros inconstans and Plinia glomerata, were evaluated for their total phenol content and antioxidant activity in different in vitro free radical scavenging models. In addition, studies were performed on cell viability of extracts of the seeds of G. achachairu against murine melanoma cells. The fruits peel and seeds of G. achachairu were very promising in terms of total phenol content (data in gallic acid equivalent per gram), as assessed by the Folin-Ciocalteu method, with values of 9.70±3.2 and 8.40±1.1, respectively. On the other hand, antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl scavenging assay showed that the fruit pulp and peel of P. glomerata presented the best profile, with values of the 16.3±1.8 and 15.9±2.4 µg/ml, respectively. Regarding the cytotoxic effect of methanol extract and guttiferone A from G. achachairu, we have observed that both inhibit the growth of B16F10 tumor cells, with calculated IC50 values of 49.6±2.1 mg/ml and 48.6±5.4 mM, respectively.

3.
AIDS Care ; 18(1): 66-72, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16282079

RESUMO

We carried out a telephone survey to assess willingness to participate in HIV vaccine trials. The survey was conducted by interviewing randomly selected callers to the Italian National AIDS Help line. The questionnaire consisted of four sections: demographic information, knowledge about HIV vaccines and vaccines in general, factors related to participation in HIV vaccine trials, and acceptability of a future HIV vaccine. Over 50% of the sample had adequate knowledge about HIV and vaccines. Among the individuals interviewed, 37% would volunteer for a vaccine trial; those reporting high-risk behaviours were more likely to volunteer. Of the participants, 83% would agree to be vaccinated with a highly effective vaccine, and 92% would pay for the vaccine. Although the limits of telephone surveys should not be neglected, the results of this survey are encouraging.


Assuntos
Vacinas contra a AIDS/uso terapêutico , Infecções por HIV/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Adolescente , Adulto , Ensaios Clínicos como Assunto , Estudos Transversais , Feminino , Infecções por HIV/psicologia , Soronegatividade para HIV , Inquéritos Epidemiológicos , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde
4.
Emerg Infect Dis ; 7(5): 893-5, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11747707

RESUMO

We studied residents of remote villages and the capital (Port Moresby) of Papua New Guinea to determine the distribution of human herpesvirus-8 (HHV-8) infection. Our data suggest that HHV-8 has been endemic on the island for a long time and that the epidemiologic pattern of HHV-8 is more similar to that of herpes simplex virus-2 than hepatitis C virus.


Assuntos
Anticorpos Antivirais/sangue , Hepacivirus/imunologia , Hepatite C/epidemiologia , Infecções por Herpesviridae/epidemiologia , Infecções por Herpesviridae/virologia , Herpesvirus Humano 8/imunologia , Adulto , Feminino , Hepatite C/virologia , Herpesvirus Humano 4/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Papua Nova Guiné/epidemiologia , População Rural , Estudos Soroepidemiológicos , Simplexvirus/imunologia , População Urbana
5.
J Med Genet ; 38(12): 824-33, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11748305

RESUMO

While sequence analysis is considered by many to be the most sensitive method of detecting unknown mutations in large genes such as BRCA1, most published estimates of the prevalence of mutations in this gene have been derived from studies that have used other methods of gene analysis. In order to determine the relative sensitivity of techniques that are widely used in research on BRCA1, a set of blinded samples containing 58 distinct mutations were analysed by four separate laboratories. Each used one of the following methods: single strand conformational polymorphism analysis (SSCP), conformation sensitive gel electrophoresis (CSGE), two dimensional gene scanning (TDGS), and denaturing high performance liquid chromatography (DHPLC). Only the laboratory using DHPLC correctly identified each of the mutations. The laboratory using TDGS correctly identified 91% of the mutations but produced three apparent false positive results. The laboratories using SSCP and CSGE detected abnormal migration for 72% and 76% of the mutations, respectively, but subsequently confirmed and reported only 65% and 60% of mutations, respectively. False negatives therefore resulted not only from failure of the techniques to distinguish wild type from mutant, but also from failure to confirm the mutation by sequence analysis as well as from human errors leading to misreporting of results. These findings characterise sources of error in commonly used methods of mutation detection that should be addressed by laboratories using these methods. Based upon sources of error identified in this comparison, it is likely that mutations in BRCA1 and BRCA2 are more prevalent than some studies have previously reported. The findings of this comparison provide a basis for interpreting studies of mutations in susceptibility genes across many inherited cancer syndromes.


Assuntos
Frequência do Gene/genética , Genes BRCA1 , Testes Genéticos/métodos , Mutação/genética , Cromatografia Líquida de Alta Pressão , Análise Mutacional de DNA/economia , Análise Mutacional de DNA/métodos , Éxons/genética , Genes BRCA2 , Predisposição Genética para Doença/genética , Testes Genéticos/economia , Humanos , Desnaturação de Ácido Nucleico , Polimorfismo Conformacional de Fita Simples , Reprodutibilidade dos Testes , Projetos de Pesquisa , Sensibilidade e Especificidade , Método Simples-Cego , Temperatura
6.
Org Lett ; 3(21): 3413-6, 2001 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-11594847

RESUMO

[reaction: see text]. Variable temperature NMR spectra of the chiral spiro[(4-N,N-dimethyldithiocarbamato)-(2-N,N-dimethylimino)-1,3-dithiolane-5,9'-xanthene] show complex dynamics including degenerate interconversion of the dithiocarbamate and iminodithiolane groups. The rate of this switching process can be controlled by chemical modification: the analogous spiro[dithiolane-fluorene] derivative shows no interconversion. These novel materials have potential application as molecular switching elements in information storage devices.

8.
Br J Cancer ; 82(7): 1249-53, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10755396

RESUMO

The intent of this study was to evaluate the effect that an awareness of being a BRCA1 or BRCA2 mutation carrier has on the attitude towards prophylactic surgery and on developing depression symptoms. Thirty-five families were selected on the basis of previously detected BRCA1 or 2 mutations and 90 family members were given the appropriate questionnaires. Prophylactic mastectomy (PM) was considered by 21% of the Austrian mutation carriers (29% affected and 8% non-affected carriers). The majority of affected and non-affected carriers expected PM to impair the quality of their life. Fifty per cent would undergo prophylactic oophorectomy (53% affected and 46% non-affected carriers). The self-rating depression scale indicated that following mutation result disclosure the depression scores of carriers decreased (40 baseline vs 38 after result disclosure, P = 0.3), whereas, for non-carriers, scores increased (36 baseline vs 40 after result disclosure, P = 0.05). We conclude that information about carrier status is not associated with increased depression symptoms in mutation carriers. In non-carriers, depression scores increased slightly, probably reflecting survivor guilt. The option of having PM was associated with a negative impact on the quality of life and was declined by the majority of Austrian mutation carriers.


Assuntos
Atitude Frente a Saúde , Neoplasias da Mama/genética , Genes BRCA1/genética , Aconselhamento Genético , Predisposição Genética para Doença , Mastectomia/psicologia , Adulto , Neoplasias da Mama/prevenção & controle , Depressão , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/prevenção & controle , Ovariectomia/psicologia , Linhagem , Qualidade de Vida
9.
J Appl Physiol (1985) ; 86(3): 825-31, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10066692

RESUMO

Pulmonary capillary perfusion was analyzed from videomicroscopic recordings to determine flow switching characteristics among capillary segments in isolated, blood-perfused canine lungs. Within each alveolus, the rapid switching pattern was repetitive and was, therefore, nonrandom (fractal dimensions near 1.0). This self-similarity over time was unexpected in a network widely considered to be passive. Among adjacent alveoli, the relationship among the switching patterns was even more surprising, for there was virtually no relationship between the perfusion patterns (coefficients of determination approaching zero). These findings demonstrated that the perfusion patterns in individual alveolar walls were independent of their next-door neighbors. The lack of dependence among neighboring networks suggests an interesting characteristic: the failure of one alveolar-capillary bed would leave its neighbors relatively unaffected, a feature of a robust design.


Assuntos
Alvéolos Pulmonares/irrigação sanguínea , Alvéolos Pulmonares/fisiologia , Circulação Pulmonar/fisiologia , Pressão Propulsora Pulmonar/fisiologia , Animais , Gasometria , Pressão Sanguínea/fisiologia , Cães , Fractais , Masculino , Microcirculação/fisiologia , Perfusão , Análise de Regressão
10.
Hum Mol Genet ; 8(3): 413-23, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9971877

RESUMO

The aim of this study was to evaluate the prevalence of simple sequence variation in the BRCA2 gene. To this end, 71 breast and breast-ovarian cancer (HBC/HBOC) families along with 95 control individuals from a wide range of ethnicities were analyzed by means of denaturing high-performance liquid chromatography (DHPLC) and direct sequence analysis. In the coding (10 257 bp) and non-coding (2799 bp) sequences of BRCA2, 82 sequence variants were identified. Three different, apparently disease-associated BRCA2 mutations were found in six HBC/HBOC families (8%): two splice site mutations in introns 5 and 21, and one frameshift mutation in exon 11. In the coding region, 53 simple sequence variants were found: 35 missense mutations, one 2 bp deletion (CT) resulting in a stop at codon 3364, one nonsense mutation with a stop at codon 3326, one deletion of a complete codon (AAA) resulting in the loss of leucine, and 15 silent mutations. In the non-coding region, 26 polymorphisms were detected. Of the 79 sequence variants that were not obviously disease-associated, eight were detected only in HBC/HBOC families. The remaining 71 variants were identified in both HBC/HBOC families and control individuals. Sixty three sequence variants (80%) were specific for a continent. Forty two percent (33 out of 79) of the sequence variants were detected exclusively in Africa, though only 13% of the 332 chromosomes screened were of African origin. Our data indicate that, in BRCA2, simple sequence variation is frequent [in the coding region 1 in 194 bp (straight theta = 2.2 x 10(-4)), and in the non-coding region 1 in 108 bp (straight theta = 4.4 x 10(-4)), respectively].


Assuntos
Neoplasias da Mama/genética , Genes Supressores de Tumor , Proteínas de Neoplasias/genética , Fatores de Transcrição/genética , África , Proteína BRCA2 , Sequência de Bases , Análise Mutacional de DNA , Primers do DNA/genética , Feminino , Frequência do Gene , Variação Genética , Humanos , Masculino , Mutação , Neoplasias Ovarianas/genética , Linhagem
13.
Int J Cancer ; 77(3): 354-60, 1998 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-9663595

RESUMO

We identified 17 BRCA1 mutations in 86 Austrian breast and ovarian cancer families (20%) that were screened for mutations by denaturing high-performance liquid chromatography (DHPLC) and the protein truncation test (PTT). Eleven distinct mutations were detected, 4 of them (962del4, 2795del4, 3135del4 and L3376stop) not previously reported in families of non-Austrian origin. In addition, 6 rare missense mutations (allele frequency < 1%) with unknown biological effects were identified. Four mutations occurred more than once in the Austrian population: 2795del4 (3 times), Cys61Gly (3 times) 5382insC (2 times) and Q1806stop (2 times). Haplotype analysis of the 4 recurrent mutations suggested a common ancestor for each of these. Thirty-four breast cancer cases from 17 families with BRCA1 mutations were further analyzed. We observed a low median age of onset (39.5 years). Sixty-eight percent of all BRCA1 breast cancer cases had negative axillary lymph nodes. This group showed a significant prevalence of a negative estrogen and progesterone receptor status and stage I tumors compared with an age-related, node-negative control group. The prevalence of grade III tumors was marginally significant. Survival analysis either with a control group matched for age (within 5 years), grade, histologic subtype and estrogen receptor status, or with an age-related, node-negative comparison group, showed no statistical difference.


Assuntos
Neoplasias da Mama/genética , Genes BRCA1 , Mutação , Neoplasias Ovarianas/genética , Adulto , Áustria , Proteína BRCA1/química , Proteína BRCA1/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/genética , Carcinoma Medular/genética , Elementos de DNA Transponíveis , Família , Feminino , Mutação da Fase de Leitura , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Mutação Puntual , Receptores de Estrogênio/análise , Receptores de Progesterona/análise , Recidiva , Deleção de Sequência , Taxa de Sobrevida
15.
Aust Vet J ; 73(5): 179-81, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8660240

RESUMO

Lame pigs, up to 12 weeks of age, were necropsied to establish a diagnosis. Of 175 pigs examined, 165 were confirmed to have arthritis by histopathological examination of joint tissues. Lesions were most common in the elbow and tarsal joints and least common in the joints of the feet. Typically, there was severe fibrinopurulent inflammation of synovial membranes regardless of the bacteria isolated. A bacterial aetiology was found in 114 (69%) of the 165 pigs. In arthritic pigs in which an aetiology was established the causative agents were Staphylococcus hyicus ssp hyicus (24.6%), Streptococcus equisimilis (26.3%), Actinomyces pyogenes (13.2%), Staphylococcus aureus (7.9%) and Haemophilus parasuis (7.9%). While gender did not affect the prevalence of arthritis, there was an age influence, most of the pigs culled for arthritis being under 6 weeks of age.


Assuntos
Artrite Infecciosa/veterinária , Infecções Estafilocócicas/veterinária , Staphylococcus/genética , Staphylococcus/fisiologia , Doenças dos Suínos/microbiologia , Actinomyces/isolamento & purificação , Envelhecimento/patologia , Animais , Artrite Infecciosa/epidemiologia , Artrite Infecciosa/microbiologia , Feminino , Haemophilus/isolamento & purificação , Articulações/microbiologia , Articulações/patologia , Coxeadura Animal/etiologia , Coxeadura Animal/patologia , Masculino , Tonsila Palatina/microbiologia , Tonsila Palatina/patologia , Prevalência , Queensland/epidemiologia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/isolamento & purificação , Streptococcus/isolamento & purificação , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/patologia , Membrana Sinovial/microbiologia , Membrana Sinovial/patologia
17.
Int J Cancer ; 56(2): 167-72, 1994 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8314296

RESUMO

Paraffin-embedded material from 69 patients with epithelial ovarian cancer FIGO stages I and II/A (including 21 patients with borderline carcinoma) was studied with automatic DNA image cytometry. Univariate analysis indicated a significant difference in survival based on the presence of nuclei with high DNA content (higher than 5 C). A group of patients with less than 0.2% cells with high DNA content had a 6-year survival of 87%, whereas in a group of patients with more than 0.2% of such cells, 6-year survival was 49%. This parameter remained significant when used in a group of stage I/a and I/b patients. Statistical analysis of diploid vs. non-diploid tumors also showed significant difference in survival. Separate analysis of 48 invasive ovarian cancers indicated that ploidy, the percentage of cells with high DNA content and tumor stage (stage I/a + b vs. stages I/c + II/a) reached significance for survival, whereas grading did not. In addition, comparison of clinical stage, grading, ploidy and the percentage of cells exceeding 5 C with a threshold at 0.2% by means of a multivariate analysis (Cox regression model) showed that only the percentage of cells exceeding 5 C remained statistically significant.


Assuntos
DNA de Neoplasias/análise , Citometria de Fluxo/métodos , Neoplasias Ovarianas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , DNA de Neoplasias/genética , Feminino , Seguimentos , Humanos , Processamento de Imagem Assistida por Computador , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Inclusão em Parafina , Ploidias , Valor Preditivo dos Testes , Prognóstico , Análise de Sobrevida
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