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1.
Langmuir ; 40(16): 8493-8502, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38602017

RESUMEN

Cationic and anionic polyelectrolytes, poly(vinylbenzyl trimethylammonium chloride) (PVBTA) and poly(sodium styrene sulfate) (PSSS), were grafted on the surface of the silica particles, respectively, and then these two types of polyelectrolyte-grafted silica particles were applied to the colloidal layer preparation by convective self-assembly (CSA) using hydrophilic or hydrophobic glass substrates to investigate the effect of the interactions between the particles and the substrate surface on the resultant layer structures. When the PVBTA-grafted silica particle (PVBTA-Si) was used, the colloidal monolayers with a non-close-packed (NCP) structure were formed on both hydrophilic and hydrophobic glass substrates, where the NCP colloidal layers on the hydrophobic glass substrate have a somewhat more ordered structure than those on the hydrophilic glass substrate. In the case of the PSSS-grafted silica particle (PSSS-Si), on the other hand, stripe patterns with close-packed (CP) colloidal layers were obtained on both types of the glass substrates. The number of layers of the stripes on the hydrophilic glass substrate was less than that on the hydrophobic glass substrate, while the spacing and width of the stripes on both substrates were similar to each other. The difference in the structures of the colloidal layers obtained here indicates that an attractive interaction, such as an electrostatic attraction and a hydrophobic interaction, between the particle and the substrate surface is necessary to achieve the NCP structure by the CSA process using polyelectrolyte-grafted silica particles.

2.
J Am Chem Soc ; 138(33): 10597-604, 2016 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-27462708

RESUMEN

A mild, general, and functional group tolerant intramolecular hydroalkoxylation and hydroacyloxylation of unactivated olefins using a Co(salen) complex, an N-fluoropyridinium salt, and a disiloxane reagent is described. This reaction was carried out at room temperature and afforded five- and six-membered oxygen heterocyclic compounds, such as cyclic ethers and lactones. The Co complex was optimized for previously rare medium ring formation by hydrofunctionalization of unactivated olefins. The powerful Co catalyst system also enables the deprotective hydroalkoxylation of O-protected alkenyl alcohol and hydroacyloxylation of alkenyl ester to afford cyclic ethers and lactones directly. The substrate scope and mechanistic proof of deprotection were investigated. The experimental evidence supports the concerted transition state of the bond-forming step involving a cationic Co complex.

3.
Biosci Biotechnol Biochem ; 80(1): 172-7, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26299992

RESUMEN

2,5-Diketopiperazines (DKPs), also called cyclic dipeptides, have been known to occur in various foods. Recently, DKPs have attracted attentions as bioactive components. There were some reports on analytical methods for DKPs, but the number of analyzed DKPs was only a part of all DKPs and the quantitative performance was not studied in detail. In this study, we selected 31 kinds of DKPs and developed a quantitative and simultaneous analytical method using LC-MS/MS. This method was applied to DKPs determination in Pu-erh tea, post-fermentation tea, and 18 kinds of DKPs were determined at concentration of 0.0017-0.11 ppm. As a result of spiked test, it was concluded that the developed method using LC-MS/MS was useful for estimating DKPs concentration in tea.


Asunto(s)
Cromatografía Liquida/métodos , Dicetopiperazinas/aislamiento & purificación , Dipéptidos/aislamiento & purificación , Péptidos Cíclicos/aislamiento & purificación , Espectrometría de Masas en Tándem/métodos , Calibración , Camellia sinensis/química , Dicetopiperazinas/química , Dipéptidos/química , Fermentación , Humanos , Límite de Detección , Péptidos Cíclicos/química , Extractos Vegetales/química , Reproducibilidad de los Resultados
4.
Dent Mater J ; 41(2): 309-316, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35082182

RESUMEN

This study aimed to determine the effects of the low concentration of fluoride sustained-released from the composite resin on properties of Streptococcus mutans (S. mutans). The proliferation, adhesion, biofilm formation, and lactic acid production of the bacterium were investigated after the treatment with fluoride from the composite resin. The activity and expression of ATPase, glucosyltransferase (GTF), and enolase were also determined by colorimetric assay and western blot analysis. Fluoride from the sustained-releasing composite resin significantly inhibited biofilm formation, adhesion, and acid production of S. mutans but did not influence the growth and ATPase activity of the bacterial strain. Fluoride-sustained-releasing composite resin inhibited adhesion, biofilm formation, and acid production of S. mutans through the suppression of GTF expression as well as the expression and activity of enolase. These resultls suggest the clinical significance of fluoride-sustained-releasing composite resin.


Asunto(s)
Resinas Compuestas , Streptococcus mutans , Biopelículas , Resinas Compuestas/farmacología , Fluoruros/metabolismo , Fluoruros/farmacología , Concentración de Iones de Hidrógeno
5.
Diagn Microbiol Infect Dis ; 101(2): 115444, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34186321

RESUMEN

Benefit of follow-up blood cultures (FUBC) in cancer patients with gram-negative bacteremia (GNB) is unknown. Multicenter, retrospective review was performed in adult cancer patients with GNB between January and December 2018. Primary outcome was FUBC incidence. Chi-square, t-tests/Wilcoxon rank-sum, and bivariate regression (logistic/Poisson) analyses compared secondary outcomes (catheter removal, ID consultation, antibiotic duration, length stay, mortality) between patients with versus without FUBC. Of 52 patients with GNB, majority (35/52; 67%) received ≥1 FUBC (mean per patient 3.6, SD 4.3, range 0-29). Majority FUBC had no growth (157/173; 90.8%). Rates of catheter removal and ID consultation were similar between groups (P > 0.05). Patients with FUBC had greater LOS (mean 21 vs 15 days; coefficient = 0.31, CI 0.17-0.45), longer duration of antibiotics (mean 13 vs 11 days, coefficient 0.19, P = 0.013), but no mortality difference (P = 1). FUBC are frequently performed yet infrequently positive in cancer patients with GNB, but were associated with increased LOS and antibiotic duration.


Asunto(s)
Bacteriemia/diagnóstico , Cultivo de Sangre/estadística & datos numéricos , Infecciones por Bacterias Gramnegativas/diagnóstico , Neoplasias/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Bacteriemia/tratamiento farmacológico , Bacteriemia/epidemiología , Femenino , Estudios de Seguimiento , Bacterias Gramnegativas/aislamiento & purificación , Infecciones por Bacterias Gramnegativas/tratamiento farmacológico , Infecciones por Bacterias Gramnegativas/epidemiología , Humanos , Incidencia , Tiempo de Internación , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
6.
Cureus ; 12(3): e7267, 2020 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-32292678

RESUMEN

Background There have been very few studies on the association of polypharmacy with clinical course. In this paper, we seek to evaluate the relationship between polypharmacy and hospitalization period. Methods We retrospectively analyzed 322 patients hospitalized from February to September 2017, after excluding short-term and orthopedic cases. Patients with polypharmacy were defined as those who were prescribed more than five drugs at the time of admission. The primary endpoint for all subjects regardless of polypharmacy was the hospitalization period. Using Mann-Whitney U test results, we compared the average number of hospital days between patients with and without polypharmacy. Secondary endpoints were hospitalization period with and without polypharmacy for each disease type. Results The hospitalization period was significantly extended for patients with polypharmacy as compared to those without (31.6 vs. 23.2 days, p: 0.002). Those with an infection had significantly longer hospitalization than those without polypharmacy (27.6 vs. 18.1 days, p: 0.007). Malignancy, heart disease, and cerebrovascular disease did not have a significant effect on hospitalization regardless of polypharmacy. Conclusion Polypharmacy is related to an extended hospitalization period and is found to occur more frequently in patients hospitalized for an infection.

7.
J Biosci Bioeng ; 104(3): 238-40, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17964492

RESUMEN

Non-growing Clostridium saccharoperbutylacetonicum N1-4 hardly produced butanol from only butyrate. As adding glucose to the medium, butyrate utilization and butanol production were stimulated. Addition of 0.1 mM methyl viologen as electron carrier resulted in the highest yield of butanol of 0.671 mol/mol to butyrate and glucose.


Asunto(s)
Butanoles/metabolismo , Butiratos/metabolismo , Técnicas de Cultivo de Célula/métodos , Clostridium/metabolismo , Glucosa/metabolismo , Paraquat/administración & dosificación , Proliferación Celular/efectos de los fármacos , Clostridium/efectos de los fármacos , Clostridium/crecimiento & desarrollo , Relación Dosis-Respuesta a Droga
8.
Dalton Trans ; 45(41): 16112-16116, 2016 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-27752666

RESUMEN

A cationic SNS-benzylpalladium complex was reacted with O2 under several conditions, affording oxygenated compounds derived from the benzyl ligand. The addition of n-Bu4NX remarkably accelerated the oxygenation, furnishing benzaldehyde as a main organic product and dinuclear complexes; in contrast, HX also promoted the oxygenation, but mainly produced benzyl hydroperoxide and mononuclear complexes.

9.
Diabetes ; 51(9): 2833-9, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12196478

RESUMEN

Accumulation of advanced glycation end products (AGEs) on tissue proteins increases with pathogenesis of diabetic complications and atherosclerosis. Here we examined the effect of peroxynitrite (ONOO(-)) on the formation of N( epsilon )-(carboxymethyl)lysine (CML), a major AGE-structure. When glycated human serum albumin (HSA; Amadori-modified protein) was incubated with ONOO(-), CML formation was detected by both enzyme-linked immunosorbent assay and high-performance liquid chromatography (HPLC) and increased with increasing ONOO(-) concentrations. CML was also formed when glucose, preincubated with ONOO(-), was incubated with HSA but was completely inhibited by aminoguanidine, a trapping reagent for alpha-oxoaldehydes. For identifying the aldehydes that contributed to ONOO(-)-induced CML formation, glucose was incubated with ONOO(-) in the presence of 2,3-diaminonaphthalene. This experiment led to identification of glucosone and glyoxal by HPLC. Our results provide the first evidence that ONOO(-) can induce protein modification by oxidative cleavage of the Amadori product and also by generation of reactive alpha-oxoaldehydes from glucose.


Asunto(s)
2-Naftilamina/análogos & derivados , Glucosa/metabolismo , Glioxal/metabolismo , Cetosas/biosíntesis , Lisina/biosíntesis , Ácido Peroxinitroso/farmacología , Albúmina Sérica/química , Tirosina/análogos & derivados , 2-Naftilamina/farmacología , Aldehídos/metabolismo , Animales , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Glucosa/farmacología , Guanidinas/farmacología , Lisina/análogos & derivados , Ratones , Ratones Endogámicos BALB C , Ácido Peroxinitroso/administración & dosificación , Tirosina/metabolismo
11.
J Biol Chem ; 281(31): 22048-22061, 2006 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-16737959

RESUMEN

Hic-5 is a focal adhesion LIM protein serving as a scaffold in integrin signaling. The protein comprises four LD domains in its N-terminal half and four LIM domains in its C-terminal half with a nuclear export signal in LD3 and is shuttled between the cytoplasmic and nuclear compartments. In this study, immunoprecipitation and in vitro cross-linking experiments showed that Hic-5 homo-oligomerized through its most C-terminal LIM domain, LIM4. Strikingly, paxillin, the protein most homologous to Hic-5, did not show this capability. Gel filtration analysis also revealed that Hic-5 differs from paxillin in that it has multiple forms in the cellular environment, and Hic-5 but not paxillin was capable of hetero-oligomerization with a LIM-only protein, PINCH, another molecular scaffold at focal adhesions. The fourth LIM domain of Hic-5 and the fifth LIM domain region of PINCH constituted the interface for the interaction. The complex included integrin-linked kinase, a binding partner of PINCH, which also interacted with Hic-5 through the region encompassing the pleckstrin homology-like domain and LIM domains of Hic-5. Of note, Hic-5 marginally affected the subcellular distribution of PINCH but directed its shuttling between the cytoplasmic and nuclear compartments in the presence of integrin-linked kinase. Uncoupling of the two signaling platforms of Hic-5 and PINCH through interference with the hetero-oligomerization resulted in impairment of cellular growth. Hic-5 is, thus, a molecular scaffold with the potential to dock with another scaffold through the LIM domain, organizing a mobile supramolecular unit and coordinating the adhesion signal with cellular activities in the two compartments.


Asunto(s)
Transporte Activo de Núcleo Celular , Proteínas del Citoesqueleto/fisiología , Proteínas de Unión al ADN/fisiología , Proteínas Adaptadoras Transductoras de Señales , Animales , Adhesión Celular , Línea Celular , Proliferación Celular , Dimerización , Adhesiones Focales , Proteínas de Homeodominio/fisiología , Proteínas con Dominio LIM , Proteínas de la Membrana , Ratones , Complejos Multiproteicos , Unión Proteica , Estructura Terciaria de Proteína
12.
Ethics Behav ; 10(1): 51-63, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11657908

RESUMEN

Some people in Japan are still comfortable with the paternalistic role of doctors, but others wish that their own decisions would receive a greater amount of respect. A total of 747 students of universities and colleges and 114 parents of these students participated in a questionnaire survey. Most of the participants thought that autonomy should be respected in situations involving death with dignity and euthanasia, whereas it should not be respected in attempted suicide and involuntary admission of individuals with mental illness. A cluster analysis revealed that the participants could be divided into the following groups: aid in dying advocates (n=577), complete libertarians (n=109), protectors of the mentally ill (n=90), complete paternalists (n=29), and questionables (n=27). The assertion of independence score of the Scale for Independent and Interdependent Construal of the Self showed a significant difference among the 5 clusters. These findings suggest that the traditional paternalistic relationship between doctor and patient is undergoing a gradual transformation in Japan.


Asunto(s)
Actitud , Discusiones Bioéticas , Bioética , Toma de Decisiones , Libertad , Participación del Paciente , Autonomía Personal , Muerte Encefálica , Internamiento Obligatorio del Enfermo Mental , Recolección de Datos , Eutanasia , Eutanasia Activa , Eutanasia Pasiva , Humanos , Japón , Padres , Paternalismo , Defensa del Paciente , Estudiantes , Suicidio , Donantes de Tejidos , Obtención de Tejidos y Órganos , Universidades
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