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1.
Org Lett ; 22(16): 6234-6238, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32584583

RESUMO

We found that the α-boryl radical of potassium alkyltrifluoroborate shows higher reactivity compared to the α-boryl radicals of alkylboronic acid pinacol ester and alkyl N-methyl imidodiacetic acid (MIDA) boronate in the halogen atom abstraction step of atom-transfer radical addition (ATRA) between alkyl bromide and vinylborons. In this research, an ATRA of alkyl halides with potassium vinyltrifluoroborate furnished unique alkylborons, which are difficult to synthesize by other methods.

2.
Mater Sci Eng C Mater Biol Appl ; 59: 690-701, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26652423

RESUMO

Selective laser melting (SLM) is an additive manufacturing technique with the ability to produce metallic scaffolds with accurately controlled pore size, porosity, and interconnectivity for orthopedic applications. However, the optimal pore structure of porous titanium manufactured by SLM remains unclear. In this study, we evaluated the effect of pore size with constant porosity on in vivo bone ingrowth in rabbits into porous titanium implants manufactured by SLM. Three porous titanium implants (with an intended porosity of 65% and pore sizes of 300, 600, and 900µm, designated the P300, P600, and P900 implants, respectively) were manufactured by SLM. A diamond lattice was adapted as the basic structure. Their porous structures were evaluated and verified using microfocus X-ray computed tomography. Their bone-implant fixation ability was evaluated by their implantation as porous-surfaced titanium plates into the cortical bone of the rabbit tibia. Bone ingrowth was evaluated by their implantation as cylindrical porous titanium implants into the cancellous bone of the rabbit femur for 2, 4, and 8weeks. The average pore sizes of the P300, P600, and P900 implants were 309, 632, and 956µm, respectively. The P600 implant demonstrated a significantly higher fixation ability at 2weeks than the other implants. After 4weeks, all models had sufficiently high fixation ability in a detaching test. Bone ingrowth into the P300 implant was lower than into the other implants at 4weeks. Because of its appropriate mechanical strength, high fixation ability, and rapid bone ingrowth, our results indicate that the pore structure of the P600 implant is a suitable porous structure for orthopedic implants manufactured by SLM.


Assuntos
Substitutos Ósseos , Implantes Experimentais , Teste de Materiais , Tíbia , Titânio , Animais , Substitutos Ósseos/química , Substitutos Ósseos/farmacologia , Porosidade , Coelhos , Tíbia/metabolismo , Tíbia/patologia , Titânio/química , Titânio/farmacologia
3.
Clin Orthop Relat Res ; 473(1): 70-5, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24777727

RESUMO

BACKGROUND: Cultural and ethnic differences are present both in subjective and objective measures of patient health, but scoring systems do not always reflect these differences, and so validation of outcomes tools in different cultural settings is important. Recently, a revised version of The Knee Society Score® (KSS 2011) was developed, but to our knowledge, the degree that this tool evaluates clinical symptoms, physical activities, and radiographic grades in the general Japanese population is not known. QUESTIONS/PURPOSES: We therefore asked: (1) how KSS 2011 reflects knee conditions and function in the general Japanese population, in particular evaluating changes with increasing patient age; (2) can objective measures of physical function be correlated with KSS 2011; and (3) does radiographic osteoarthritis (OA) grade correlate with KSS 2011? METHODS: Two hundred twenty-six people in the general Japanese population, aged 35 to 92 years, with and without knee arthritis, voluntarily participated in this cross-sectional study. Residents who had no serious disease or symptoms based on a self-assessment were recruited. This study consisted of a questionnaire including self-administered KSS 2011, physical examination, and weightbearing radiographs of the knee. Leg muscle strength, Timed Up and Go test, and body mass index (BMI) were examined in all the participants. Radiographs were graded according to the Kellgren and Lawrence scale (KL grade). RESULTS: Multivariable linear regression analysis showed that KSS 2011 correlated with age (coefficient: -0.30±0.12, p=0.011), BMI (coefficient: -1.47±0.42, p<0.001), leg muscle strength (coefficient: 0.41±0.13, p=0.002), and Timed Up and Go Test (coefficient: -1.96±0.92, p=0.034), but not sex, as independent variables by a stepwise method. KSS 2011 was also correlated with radiographic OA evaluated by KL grade (coefficient: -12.2±2.9, p<0.001). CONCLUSIONS: KSS 2011 reflects symptoms, physical activities, and radiographic OA grades of the knee in an age-dependent manner in the general Japanese population. LEVEL OF EVIDENCE: Level IV, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.


Assuntos
Povo Asiático , Articulação do Joelho/fisiopatologia , Atividade Motora , Osteoartrite do Joelho/diagnóstico , Inquéritos e Questionários , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Japão/epidemiologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Força Muscular , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/etnologia , Osteoartrite do Joelho/fisiopatologia , Exame Físico , Valor Preditivo dos Testes , Radiografia , Índice de Gravidade de Doença
4.
Chem Commun (Camb) ; 50(76): 11169-72, 2014 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-25111425

RESUMO

The chiroptical properties of an anionic meso-tetrakis(4-sulfonatophenyl)porphyrin (TPPS) complexed with cationic surfactants were enhanced by interaction with silver nanoparticles (AgNPs) in acidic solution. Improvement in chiroptical properties was revealed by circular dichroism (CD) and circularly polarized luminescence (CPL), with |gabs| and |glum| values reaching 0.05 and 0.001 at 303 K, respectively.

5.
Chem Asian J ; 1(6): 860-7, 2006 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-17441129

RESUMO

The self-aggregation behavior of C60 fullerenes that bear two octadecyl chains (lipid 1) as well as the structures and electrochemical properties of cast films of 1 are described. We also examined the self-aggregation behavior in organic solvents of three previously reported compounds: C60 with three each of hexadecyl (lipid 2), tetradecyl (lipid 3), or dodecyl (lipid 4) chains. The fullerene lipids in alcohols spontaneously formed spherical aggregates, whose diameters are related to the alkyl-chain lengths, concentrations of the fullerene lipids, and the solvent polarity. The morphologies of the aggregates showed temperature dependence. Cast films of 1 formed multimolecular bilayer structures that undergo a phase transition typical of lipid bilayer membranes. The electrochemistry of cast films of 1 on an electrode in aqueous medium exhibits temperature dependence.

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