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1.
J Am Chem Soc ; 132(32): 11000-1, 2010 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-20666357

RESUMEN

A linear polymer, hyperbranched polymers with various degrees of branching, and 100% hyperbranched polymers were successfully synthesized by self-polycondensation of 2,2,2-trifluoro-1-[4-(4-phenoxyphenoxy)phenyl]ethanone by using different amounts of trifluoromethanesulfonic acid from the same AB(2) monomer.

2.
ACS Omega ; 5(13): 7096-7105, 2020 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-32280850

RESUMEN

Rare-earth (RE) phosphates often appear as an accessory phase in igneous or metamorphic rocks; however, these rocks are composed of myriad chemical elements and nuclides that interfere with the qualitative or quantitative analyses of the RE phosphates over a range of concentrations in the absence of a pretreatment. In addition, the limit of each analytical methodology constrains the approach as well as the usefulness of the results in geoscience applications. Here, we report the specific mineral characterization of RE-containing ores from Yen Phu mine, Vietnam, using a range of state-of-the-art spectroscopic techniques in conjunction with microscopy: Mössbauer spectroscopy, infrared microspectroscopy, time-resolved laser-induced fluorescence spectroscopy (TRLFS), and scanning electron microscopy with energy-dispersive X-ray spectroscopy. Because the distribution of each element in the deposit differs, such combinatorial works are necessary and could lead to more plausible answers to questions surrounding the point of origin of RE elements. The results of our Mössbauer spectroscopic analysis indicate that the three ores sampled at different locations all contain magnetite-like, hematite-like, and iron(III) salts other than hematite. In addition, we confirmed the presence of phosphate around the grain boundary in the magnetite-like mineral phase by infrared microspectroscopic analysis. The present analytical findings of trace amounts of europium(III) using TRLFS suggest that the europium ions generate identical luminescence spectra despite being embedded in three different matrices of iron minerals. This demonstration highlights the benefits of combinatorial spectroscopic analyses to gain insights into the effects of the environment of REs on their solid-state chemistry and shows the potential utility of TRLFS as a resource mining tool. Further applications of this approach in the analytical screening of rocks and minerals are feasible.

3.
Kansenshogaku Zasshi ; 76(6): 432-8, 2002 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-12136651

RESUMEN

Although various cell lines have been used for virus isolation, few study of virus isolation using MRC-5 cell, a human embryonic lung fibroblasts, have been reported in Japan. MRC-5 and other cell lines (Caco-2, Vero, RD-18s, LLC-MK2, HeLa, MDCK, FL, B95a and HMV-II), and suckling mouse were compared for isolation of viruses from clinical specimens. A total of 3,284 specimens, collected from clinics and hospitals in Saitama Prefecture between July 1997 and August 2001, were inoculated in these cells. A total of 1,252 viral strains were isolated and 1,190 viral strains of these were identified. MRC-5 detected 209 of specimens positive for various viruses. As for adenovirus, a total of 132 viral strains were isolated using cell lines described above, and 100 of 132 viral strains were isolated in MRC-5. MRC-5 showed the highest sensitivity for isolation of adenovirus 3 and 7 (79.1% and 100%) of all other cells. The sensitivity in isolation of these viruses in HeLa was 58.1% and 50.0%, respectively. It showed that MRC-5 is able to isolate enterovirus, especially coxsackie virus A16 and enterovirus 71 with a high sensitivity (85.7% and 73.7%). RD-18s detected 35.7% and 26.3% of coxsackie virus A16 and enterovirus 71 isolates, LLC-MK2 detected 60.7% and 47.4%, and Vero detected 48.6% and 52.6%, respectively. Coxsackie virus B group was not isolated, except for a few coxsackie virus B 5 strains. Enteroviruses except coxsackie virus A16 and enterovirus 71 were isolated more frequently in Caco-2 and RD-18s. Seven hundred thirteen strains of influenza viruses were isolated in MDCK and Caco-2, but none was isolated in MRC-5. It was probably due to the maintenance medium without trypsin. The isolation rate of herpes simplex virus in Vero was 88.9% and MRC-5 showed 77.8%, it was high secondary to Vero by MRC-5. However, the CPE was detected in a few days in MRC-5, it was earlier than in Vero. The MRC-5 is possible to be maintained without changing the maintenance medium and passaged for 2 weeks, and clear CPE was observed. On the other hand, the disadvantages in using the MRC-5 were that the passage was limited and that the split ratio was only 1:2. However, the MRC-5 was used successfully for virus isolation, especially coxsackie virus A16, enterovirus 71 and adenoviruses, from clinical specimens.


Asunto(s)
Adenoviridae/aislamiento & purificación , Enterovirus/aislamiento & purificación , Fibroblastos/virología , Pulmón/citología , Humanos , Pulmón/embriología
4.
Microbiol Immunol ; 50(3): 179-85, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16547415

RESUMEN

We performed a molecular epidemiological study on the envelope glycoprotein gene (E1 gene) obtained by PCR amplification from specimens of 17 rubella patients in certain areas (Gunma, Saitama, and Kagoshima prefectures, and Tokyo metropolitan area) in Japan in 2004. In these sequences of partially amplified DNAs (283 bases) within the E1 gene, no nucleotide substitution was observed. They were classified into genotype 1D of clade 1 in the constructed phylogenetic tree. One amino acid substitution was found between the amino acid sequence predicted from these DNAs and those of Japanese strains [To-336 vaccine strain (To-336 vac) and its wild progenitor (To-336 wt)]. The results suggest that the rubella viruses (RV) prevalent in certain areas of Japan in 2004 were highly homologous and were closely related with Japanese vaccine strain.


Asunto(s)
Filogenia , Virus de la Rubéola/genética , Rubéola (Sarampión Alemán)/epidemiología , Proteínas del Envoltorio Viral/genética , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Japón/epidemiología , Masculino , Datos de Secuencia Molecular , Rubéola (Sarampión Alemán)/virología , Análisis de Secuencia de ADN
5.
J Med Virol ; 75(3): 470-4, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15648065

RESUMEN

A rapid, sensitive, and specific assay to detect mumps virus RNA directly from clinical specimens using a real-time PCR assay was developed. The assay was capable of detecting five copies of standard plasmid containing cDNA from the mumps virus F gene. No cross-reactions were observed with other members of Paramyxoviridae, or with viruses or bacteria known to be meningitis pathogens. Seventy-three clinical samples consisting of throat swabs collected from patients with parotitis, and cerebrospinal fluid (CSF) collected from patients with aseptic meningitis, were examined with a real-time PCR assay developed by the authors, reverse-transcription nested-PCR (RT-n-PCR), and virus isolation using cell culture. Like the RT-n-PCR assay, the real-time PCR assay could detect mumps virus RNA in approximately 70% of both throat swabs and CSF samples, while, by tissue culture, mumps virus was isolated from only approximately 20% of CSF and 50% of throat swab samples. In addition, the real-time PCR assay could be developed easily into a quantitative assay for clinical specimens containing more than 1,800 copies of mumps virus RNA/ml by using serial dilutions of the standard plasmid. The results suggest that the real-time PCR assay is useful for identification of mumps virus infections, not only in typical cases, but also in suspected cases, which show only symptoms of meningitis or encephalitis.


Asunto(s)
Virus de la Parotiditis/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , ARN Viral/análisis , Humanos , Meningitis Aséptica/virología , Paperas/virología , Virus de la Parotiditis/genética , Virus de la Parotiditis/crecimiento & desarrollo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad , Proteínas Virales de Fusión/genética , Virología/métodos
6.
Microbiol Immunol ; 47(2): 167-72, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12680721

RESUMEN

Mumps virus (MuV) strains isolated in Saitama Prefecture, Japan, from 1997 to 2001, were examined by analyzing the SH and the F gene nucleotide sequences. The results of the SH gene analysis showed that only genotype G was found in 2001 as well as in 2000, and that genotype J, which we proposed as a new genotype in a previous study, was from a different lineage than the genotype J described by Tecle et al. (J. Gen. Virol. 82, 2675-2680). We therefore, propose to rename the genotype as K to avoid confusion. Then, the F gene of genotypes G, H, and K strains were analyzed together with previously reported strains in this study. The results of phylogenetic analysis of the F gene nucleotide sequences showed that these strains formed a cluster as described by the SH gene analysis. Alignment of the F amino acid sequences showed that the F protein was well conserved among strains of different genotypes with a few amino acid differences. These results provide better information for the characterization of contemporary MuV strains in Japan.


Asunto(s)
Virus de la Parotiditis/clasificación , Virus de la Parotiditis/aislamiento & purificación , Paperas/virología , Análisis de Secuencia de ADN , Proteínas Virales de Fusión/genética , Secuencia de Aminoácidos , Niño , Preescolar , ADN Viral/análisis , Femenino , Genotipo , Humanos , Japón , Masculino , Datos de Secuencia Molecular , Virus de la Parotiditis/genética , Virus de la Parotiditis/metabolismo , Filogenia , Reacción en Cadena de la Polimerasa , Proteínas Virales de Fusión/química , Proteínas Virales/química , Proteínas Virales/genética
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