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1.
J Appl Microbiol ; 105(5): 1441-51, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18828791

RESUMO

AIMS: In the present study, we focused on one of the Aeromonas veronii isolates that exhibited marked adhesion onto carp intestine and studied its membrane-associated proteins for their possible involvement in mucosal adhesion. METHODS AND RESULTS: We isolated a strain of Aer. veronii (CWP11) that exhibited a high degree of temperature-dependent adhesion activity onto carp intestinal tract and studied its adhesion factor. A proteomic analysis of the membrane-associated fraction showed the presence of multiple proteins that were specifically expressed in CWP11 cells cultured at 25 degrees C. Of these, a 30 kDa protein was identified to be OmpA by a mass fingerprint analysis. Cloning and nucleotide sequencing of the ompA region of CWP11 revealed the presence of two tandem ompA homologues (ompAI-ompAII). Escherichia coli that expressed either OmpAI or OmpAII exhibited marked adhesion onto carp intestinal surface. Disruption of ompAI by a homologous recombination technique resulted in marked reduction of the adhesion activity in CWP11. CONCLUSION: The OmpA homologue plays an important role in the adhesion of the Aer. veronii strain onto the surface of intestinal tract. SIGNIFICANCE AND IMPACT OF THE STUDY: We successfully identified an OmpA homologue to be an adhesion factor of Aer. veronii, an optimistic pathogen that habituates in carp intestinal tract.


Assuntos
Aeromonas/fisiologia , Aderência Bacteriana/fisiologia , Proteínas da Membrana Bacteriana Externa , Carpas/microbiologia , Mucosa Intestinal/microbiologia , Aeromonas/genética , Animais , Aderência Bacteriana/genética , Proteínas da Membrana Bacteriana Externa/genética , DNA Bacteriano/genética , Escherichia coli/genética , Doenças dos Peixes/microbiologia , Proteoma , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA
2.
J Appl Microbiol ; 102(5): 1307-17, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17448166

RESUMO

AIMS: The aims of the present study are to characterize the intestinal microbial community displaying a high-adhesive capability in fish, and to evaluate the relationship between mucosal adhesion of intestinal bacteria and fish health and disease. METHODS AND RESULTS: A total of 707 aerobic bacteria isolated from carp intestine that were maintained under either feeding (feeding group) or no-feeding (no-feeding group) conditions and were performed adhesive assay. Isolates were divided into three categories on the basis of adhesive capability: high-, medium-, and low- adhesive capabilities. The average proportions of isolates with high-adhesive capability in the feeding and no-feeding groups were 30% and 32%, respectively. A phylogenetic analysis using a partial 16S rRNA gene demonstrated that most isolates with high-adhesive capability in both groups were classified as belonging to an Aeromonas group, and populations of isolates within high- and low-adhesive categories were markedly different. CONCLUSIONS: Intestinal bacteria with a high-adhesive capability in relation to intestinal mucous always colonize on the surface of intestinal mucosa and grow in the intestinal tract of feeding carp. The adhesive capability of intestinal bacteria is essential for colonization and growth in the intestinal tract of fish. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results indicate that members of the Aeromonas group with adhesive capability always colonize on the surface of intestinal mucosa.


Assuntos
Bactérias/classificação , Técnicas de Tipagem Bacteriana/métodos , Carpas/microbiologia , DNA Bacteriano/genética , Mucosa Intestinal/microbiologia , Filogenia , Animais , Aquicultura , Bactérias/isolamento & purificação , Aderência Bacteriana , Doenças dos Peixes/microbiologia
3.
Theor Appl Genet ; 105(2-3): 222-228, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12582523

RESUMO

Self-compatible cultivars of Japanese apricot ( Prunus mume Shieb. et Zucc.), a tree species that normally shows S-RNase-based self-incompatiblity, have a horticultural advantage over self-incompatible cultivars. Inheritance of self-compatibility and a common S(f)-RNase allele that is observed in self-compatible cultivars was investigated using progenies from controlled crosses. Total DNAs were isolated from the parents and progenies of seven crosses that included at least one self-compatible cultivar as a parent. These DNAs were PCR-amplified with the Pru-C2 and PCE-R primer pair to determine S-haplotypes of the parents and progenies. A novel S-haplotype, S(8), was found. In all crosses examined, the S(f)-RNase gene was inherited from either the seed or pollen parent as a pistil S-allele in a non-functional S-haplotype. Self-compatibility of about 20 trees each from reciprocal crosses of 'Benisashi ( S(7) S(f))' and 'Shinpeidayu ( S(3) S(f))', and 26 selections from 16 different crosses was tested by pollination and pollen-tube growth studies. Cosegregation of the S(f)-RNase allele and self-compatibility was confirmed with all but selection 1K0-26 ( S(3) S(7)). Selection 1K0-26 ( S(3) S(7)) that originated from 'Benisashi ( S(7) S(f))' x 'Koshinoume ( S(3) S(f))' appeared to be self-compatible even without the S(f)-RNase allele. The possible role of pollen- S, a presumably existing pollen component of gametophytic self-incompatibility, is discussed.

4.
Auris Nasus Larynx ; 28 Suppl: S7-11, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11683347

RESUMO

Branchio-oto (BO) syndrome is complicated with congenital preauricular fistulae, branchial fistulae (cysts), and hearing loss (sensorineural, conductive or mixed). As well as branchio-oto-renal (BOR) syndrome. it is known to be an autosomal dominant hereditary disorder. Since mutations in the EYA1 gene have been identified in both BO and BOR syndromes, mutation screening of this gene has been drawing attention as a genetic test to diagnose BOR/BO syndromes. In this study, we genetically investigated the presence of EYA1 mutations in a BO syndrome family in which we observed congenital preauricular fistulae, branchial fistulae (cysts) and hearing loss in four generations. Whereas there was a variety of phenotype expressions in this family, all subjects tested had a nonsense mutation (R264X) in exon 8 of the EYA1 gene. The present report adds further examples to support the usefulness of molecular genetic testing for the diagnosis of patients with BO syndrome.


Assuntos
Síndrome Brânquio-Otorrenal/genética , Transativadores/genética , Criança , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Mutação , Proteínas Nucleares , Linhagem , Proteínas Tirosina Fosfatases
5.
J Hum Genet ; 46(9): 518-21, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11558900

RESUMO

Mutation analysis of the PDS gene and the EYA1 gene, which are reported to be responsible for hearing loss associated with ear anomalies, was performed in 24 deaf patients with various middle and inner ear anomalies. The present study was done to clarify the spectrum of middle and inner ear malformations covered by these two genes. PDS mutations were found only in patients with enlarged vestibular aqueducts and EYA1 mutations were detected only in patients with ear pits and cervical fistulae, indicating that these two genes are associated with particular forms of middle and inner ear malformation. The genetic approach provides a strong tool for the diagnosis of hearing loss associated with ear anomalies.


Assuntos
Proteínas de Transporte/genética , Anormalidades Congênitas/genética , Surdez/genética , Orelha/anormalidades , Proteínas de Membrana Transportadoras , Mutação , Transativadores/genética , Adolescente , Adulto , Criança , Análise Mutacional de DNA , Surdez/etiologia , Feminino , Genes Dominantes , Genes Recessivos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares , Proteínas Tirosina Fosfatases , Transportadores de Sulfato
6.
J Org Chem ; 66(11): 3775-82, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11374997

RESUMO

NMR chemical shifts have been experimentally measured and theoretically estimated for all the carbon atoms of (1R,3S,4S,8S)-p-menthane-3,9-diol in chloroform solution. Theoretical estimations were performed using a combination of molecular dynamics simulations and quantum mechanical calculations. Molecular dynamics simulations were used to obtain the most populated conformations of the (1R,3S:4S,8S)-p-menthane-3,9-diol as well as the distribution of the solvent molecules around it. Quantum mechanical calculations of NMR chemical shifts were performed on the most relevant conformations employing the GIAO-DFT formalism. A special emphasis was put in evaluating the effects of the surrounding solvent molecules. For this purpose, supermolecule calculations were performed on complexes constituted by the solute and n chloroform molecules, where n ranges from 3 to 16. An excellent agreement with experimental data has been obtained following this computational strategy.

7.
J Comput Aided Mol Des ; 15(3): 235-45, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11289077

RESUMO

A set of amphiphilic p-menthan-3,9-diols have been investigated by molecular dynamics simulations. These are four stereoisomers than can be specifically obtained from two terpenoids widely used in biorganic chemistry. For this purpose, the p-menthan-3,9-diols have been explicitly parametrized using both semiempirical and ab initio quantum mechanical calculations. The reliability of these parameters has been validated by predicting different molecular and thermodynamic properties. Molecular dynamics simulations in aqueous solution have been performed with the new parameters. The results provide useful insights about the conformational properties of this family of compounds and the formation of intra- and intermolecular hydrogen bonds.


Assuntos
Tensoativos/química , Terpenos/química , Desenho de Fármacos , Ligação de Hidrogênio , Modelos Moleculares , Conformação Molecular , Eletricidade Estática , Termodinâmica
8.
J Med Genet ; 37(1): 38-40, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10633132

RESUMO

The frequency of three mitochondrial point mutations, 1555A-->G, 3243A-->G, and 7445A-->G, known to be associated with hearing impairment, was examined using restriction fragment length polymorphism (RFLP) analysis in two Japanese groups: (1) 319 unrelated SNHL outpatients (including 21 with aminoglycoside antibiotic injection history), and (2) 140 cochlear implantation patients (including 22 with aminoglycoside induced hearing loss). Approximately 3% of the outpatients and 10% of the cochlear implantation patients had the 1555A-->G mutation. The frequency was higher in the patients with a history of aminoglycoside injection (outpatient group 33%, cochlear implantation group 59%). One outpatient (0.314%) had the 3243A-->G mutation, but no outpatients had the 7445A-->G mutation and neither were found in the cochlear implantation group. The significance of the 1555A-->G mutation, the most prevalent mitochondrial mutation found in this study of a hearing impaired population in Japan, among subjects with specific backgrounds, such as aminoglycoside induced hearing loss, is evident.


Assuntos
DNA Mitocondrial/genética , Perda Auditiva Neurossensorial/genética , Mutação Puntual , Polimorfismo de Fragmento de Restrição , Aminoglicosídeos , Antibacterianos/efeitos adversos , Implante Coclear , DNA Mitocondrial/sangue , Perda Auditiva Neurossensorial/induzido quimicamente , Perda Auditiva Neurossensorial/cirurgia , Humanos , Japão
9.
Artigo em Inglês | MEDLINE | ID: mdl-18263209

RESUMO

An asynchronous spread spectrum (SS) modem in the 2.45-GHz band has been implemented using an efficient ZnO-SiO(2)-Si surface acoustic wave (SAW) convolver. The modem, which can operate under full duplex transmission is based on a direct-sequence/code-shift-keying (DS/CSK) method for the modulation. Pseudonoise (PN) codes are chosen from a preferred pair of m-sequences of period 127, and the code rate is 14 MHz. The demodulation is carried out asynchronously, utilizing the coherent correlation characteristics of the SAW convolver. The main interference caused by a transmitted signal in the modem itself is effectively reduced by an RF isolator and the SS process gain. Adequate self-jamming rejection capability has been confirmed; a bit error rate of 10(-6) is observed at -78.3 dB of a desired-to-undesired-signal ratio using an artificial transmission line.

10.
Front Med Biol Eng ; 4(1): 47-54, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1599883

RESUMO

Presented here is a new method of optically detecting agglutination reactions through counting the number of level-crossings of light intensity fluctuations scattered by coated carrier particles. The theory behind this technique is that the number of level-crossings decreases as the size of aggregated particles and, accordingly, the antigen concentration increases. The antigen used in this experiment is immunoglobulin E (IgE). The crossing level is fixed at the average intensity of the scattered light. The detectable range is from 17 to 1000 IU/ml under this condition. The incubation time is 15 min. The coefficient of variations (CVs) of the number of level-crossings is reasonably low, between 0.382 and 3.05% (n = 5). Through simple data processing involving comparison of the data with the crossing level and counting the number of level-crossings, it is possible to determine the antigen concentration on a real time basis.


Assuntos
Testes de Aglutinação/métodos , Reações Antígeno-Anticorpo , Imunoensaio/métodos , Imunoglobulina E/análise , Matemática
11.
Front Med Biol Eng ; 3(2): 113-22, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1716971

RESUMO

A new optical method is presented here for detecting immunoreaction by means of the forward and depolarized light scattering by coated carrier particles. By this approach, a short-time measurement of antigen-antibody reactions was concisely achieved. The method covered in this article is based on using double-scattered light. While light that is single-scattered by microspheres is polarized parallel to the incident light polarization, double-scattered light contains depolarized components. The normalized fractional variance in the single-scattered field is inversely proportional to the particle concentration, whereas that in the double-scattered field is inversely proportional to the square of the particle concentration. Due to this difference, the decrease of the particle concentration during the agglutination reaction is more sensitively detected through the measurement of the fractional variance in the double-scattered field. In addition, undesirable light scattered from non-aggregated microspheres is reduced by using the method summarized here. This study is based on the assumption that the particle concentration of the double-scattered field is 4.5 x 10(11) particles/cm3. The latex spheres coated with antibody molecules aggregated after adding the antigen and, as a result, the fractional variance rapidly increased before leveling off after 5-10 min. The antigens measured were alpha-fetoprotein (AFP) and immunoglobulin E (IgE).


Assuntos
Imunoensaio/métodos , Luz , Microesferas , Reações Antígeno-Anticorpo , Desenho de Equipamento , Imunoglobulina E/análise , Lasers , Látex , alfa-Fetoproteínas/análise
15.
Doc Ophthalmol ; 47(1): 147-62, 1979 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-520139

RESUMO

Measurements of Constrast Sensitivity Functions (CSF) were made on normal observers made artificially highly ametropic with spectacle lenses (with high back vertex) distance in order to determine the effect of retinal image size alterations upon CSF measures. While not an exact model for high ametropia per se, this experiment served to familiarize the experimenters with problems associated with the task. Image size alterations occur normally in aphakic patients and highly myopic patients. As a clinical trial, a series of aphakic observers were tested using an interferometric acuity device. CSF measures were made with the patient's spectacle corrections in place and again with correcting contact lenses substituted. The contact lenses reduce induced image size alterations in these cases. The use of contact lenses in such measures allows differentiation between artifactual low frequency fall off in aphakia due to lens effects and possible low frequency fall-off due to other causes.


Assuntos
Afacia/fisiopatologia , Erros de Refração/diagnóstico , Acuidade Visual , Adulto , Lentes de Contato , Óculos , Humanos , Masculino , Métodos , Pessoa de Meia-Idade , Refração Ocular
17.
AJR Am J Roentgenol ; 131(2): 317-20, 1978 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-150212

RESUMO

The diagnosis of infected synthetic grafts is difficult using traditional radiographic techniques. In four cases, computed tomography demonstrated small pockets of gas in the clot around the grafts, a distinctive finding for an infected prosthesis. Further experience is required to determine whether this will prove to be a reliable diagnostic sign. The gas collections in infected grafts differ from normal gas in their multiplicity and occurrence more than 10 days after surgery.


Assuntos
Infecções Bacterianas/diagnóstico por imagem , Prótese Vascular , Complicações Pós-Operatórias/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso , Aorta/cirurgia , Gases , Humanos , Masculino , Polietilenotereftalatos
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