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1.
Chem Commun (Camb) ; 59(80): 11979-11982, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37724566

RESUMEN

Controlled aggregation of dyes is crucial to achieve their desired optical and electronic properties. Here, we report the induction of chiral J-aggregation of carbocyanine dyes by using lysine-derived amphiphile assemblies as scaffolds in water. The molecular structure of the amphiphiles affected the packing of the assembly. The tight packing with some flexibility promoted the formation of J-aggregates of the dyes with strong chiroptical properties.

2.
Injury ; 53(6): 2297-2303, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35260245

RESUMEN

INTRODUCTION: Recent studies on posterior malleolar fractures mainly focus on the reduction quality and fixation of the posterior fragment since it contributes to ankle stability and articular congruency. However, the association of pre-and postoperative factors considering the whole ankle joint in postoperative functional outcomes remains unclear. Therefore, this study aimed to examine the association between pre-and postoperative variables for postoperative functional outcomes in patients with posterior malleolar fragments (classified as Haraguchi type I or II) and considered the association between reduction and fixation for small posterior malleolar fragments of less than 25% of the intra-articular surface. METHODS: This multicenter retrospective cohort study included 110 adult patients who underwent internal fixation for ankle fractures with posterior malleolar fragments. The primary outcome was the American Orthopaedic Foot and Ankle Society (AOFAS) score 12-months postoperatively. As pre-and postoperative variables, the preoperative demographic data, radiographic findings, operative method, postoperative radiographic findings, and complications were evaluated. In addition, univariable and multivariable logistic regression analyses were conducted to examine the association between pre-and postoperative variables and AOFAS scores. RESULTS: Twenty-four (21.8%) cases had postoperative complications. Univariate analysis showed that age was significantly according to AOFAS score-stratified groups in patients with Haraguchi type II fractures. Multivariable logistic regression analysis using bootstrapping in the Haraguchi type II group showed that postoperative complications were significantly associated with low AOFAS scores, indicating poor functionality. In both fracture types, postoperative complications had the highest odds ratio among the explanatory variables. In patients with small posterior malleolar fragments, fragment reduction, fixation, and ankle stability were not associated with AOFAS scores. CONCLUSIONS: Our results suggest that postoperative complications were associated with AOFAS scores at postoperative 12 months in patients with ankle fractures with posterior malleolar fragments. In patients with small posterior malleolar fragments, reduction and fixation were not associated with AOFAS scores. Therefore, clinical decisions for posterior fragment fixation should be made based on the possible risk of complications related to the surgical procedures in addition to the posterior malleolar fragment size.


Asunto(s)
Fracturas de Tobillo , Adulto , Fracturas de Tobillo/diagnóstico por imagen , Fracturas de Tobillo/cirugía , Fijación Interna de Fracturas , Humanos , Complicaciones Posoperatorias/diagnóstico por imagen , Estudios Retrospectivos , Resultado del Tratamiento
3.
Injury ; 53(3): 1190-1195, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34749907

RESUMEN

INTRODUCTION: Proximal peri-implant femoral fractures occur following intramedullary nailing (IMN) fixation for trochanteric, femoral shaft, and distal femoral fractures. However, analyses of secondary hip fractures (SHFs) using large clinical samples are lacking. Therefore, we aimed to report the incidence and clinical outcomes of SHF after nailing fixation (IMN or cephalomedullary nailing [CMN]) for overall femoral fractures. In addition, we focused on IMN for femoral shaft fractures and investigated the risk factors for SHF. METHODS: This multicenter, retrospective, cohort study included 2,293 patients aged > 60 years who underwent nailing fixation for femoral fractures. The primary outcome was the incidence of SHF. In the assessment of clinical outcomes, we evaluated reoperation and the regaining of walking ability following SHF management. In addition, we conducted multivariable logistic regression analyses to examine the association between risk factors and SHF. RESULTS: Seventeen (0.7%) patients had SHFs, including 12 femoral neck fractures and 5 trochanteric fractures. Antegrade IMN was the most common type of nailing fixation. Multivariable analysis demonstrated that the absence of femoral head fixation was significantly associated with the incidence of SHF following IMN for femoral shaft fractures (odds ratio, 17.0; 95% confidence interval, 1.9-2265.7; p=0.006). In the assessment of clinical outcomes, there were two reoperations (16.7%) in the secondary femoral neck fracture group. Patients with secondary trochanteric fractures tended to have a lower probability of regaining walking ability than those with secondary femoral neck fractures (20% vs. 50%). CONCLUSIONS: In this multicenter study, the incidence of SHF after nail fixation for femoral fractures was 0.7%. The absence of femoral head fixation was significantly associated with SHF, and the clinical outcomes were poor. Therefore, femoral head fixation at the initial IMN fixation for femoral fractures may be a fixation option for surgeons to consider as an SHF prevention measure.


Asunto(s)
Fracturas del Fémur , Fijación Intramedular de Fracturas , Fracturas de Cadera , Clavos Ortopédicos , Estudios de Cohortes , Fracturas del Fémur/diagnóstico por imagen , Fracturas del Fémur/etiología , Fracturas del Fémur/cirugía , Fijación Intramedular de Fracturas/efectos adversos , Fracturas de Cadera/diagnóstico por imagen , Fracturas de Cadera/etiología , Fracturas de Cadera/cirugía , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
4.
J Vet Res ; 65(1): 73-78, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33817398

RESUMEN

INTRODUCTION: The purpose of this study was to determine the effects of vitamin C supplementation on blood oxidative stress biomarkers and antibody response to vaccination in calves. MATERIAL AND METHODS: Thirty-four clinically healthy 2 week old Japanese Black calves were randomly assigned to two groups. Seventeen calves formed the VC group which received 1,000 mg of vitamin C daily from 2 to 8 weeks of age, and the other 17 calves of the control group did not receive supplementation. All calves received an inactivated Histophilus somni vaccine at 4 and 8 weeks of age. Blood samples were taken at 2, 4, 8 and 12 weeks of age. RESULTS: The concentration of the serum reactive oxygen metabolites (d-ROMs), and the oxidative stress index (OSI), which is calculated from the d-ROMs and biological antioxidant potential, were significantly lower at 8 weeks of age in the VC group than in the control group (P < 0.05). The antibody titres to H. somni in the VC group were significantly higher than those in the control group at 12 weeks of age after the second vaccination (P < 0.05). CONCLUSION: Vitamin C supplementation to calves may reduce oxidative stress and enhance the antibody production after vaccination with H. somni.

5.
J Nutr Sci Vitaminol (Tokyo) ; 66(4): 381-385, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32863313

RESUMEN

The purpose of this study was to determine the effect of beta-carotene supplementation to Japanese Black calves on the peripheral blood leukocyte population. Twenty-two Japanese Black calves were alternately assigned to two groups. Eleven calves received 20 mg/d of beta-carotene orally from 2 to 8 wk of age (BC group), and the other 11 calves did not receive (control group). The serum beta-carotene concentration in the BC group at 4, 8 and 12 wk of age were significantly higher than those in the control group (p<0.05). The numbers of CD4+ cells in the BC group were significantly higher than those in the control group at 4 wk of age (p<0.05). These results confirmed that beta-carotene supplementation to Japanese Black calves affected the peripheral blood leukocyte population.


Asunto(s)
Linfocitos T CD4-Positivos , Bovinos/inmunología , Suplementos Dietéticos , Leucocitos , beta Caroteno/administración & dosificación , Animales , Bovinos/sangre , Recuento de Leucocitos , Vitamina A/sangre , beta Caroteno/sangre
6.
J Chem Phys ; 151(4): 044105, 2019 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-31370541

RESUMEN

We consider a rotationally invariant system-bath (RISB) model in three-dimensional space that is described by a linear rigid rotor independently coupled to three harmonic-oscillator baths through functions of the rotor's Euler angles. While this model has been developed to study the dielectric relaxation of a dipolar molecule in solvation as a problem of classical Debye relaxation, here we investigate it as a problem of open quantum dynamics. Specifically, the treatment presented here is carried out as an extension of a previous work [Y. Iwamoto and Y. Tanimura, J. Chem. Phys 149, 084110 (2018)], in which we studied a two-dimensional (2D) RISB model, to a three-dimensional (3D) RISB model. As in the 2D case, due to a difference in the energy discretization of the total Hamiltonian, the dynamics described by the 3D RISB model differ significantly from those described by the rotational Caldeira-Leggett model. To illustrate the characteristic features of the quantum 3D rotor system described by angular momentum and magnetic quantum numbers, we derive a quantum master equation (QME) and hierarchical equations of motion for the 3D RISB model in the high-temperature case. Using the QME, we compute linear and 2D rotational spectra defined by the linear and nonlinear response functions of the rotor dipole, respectively. The quantum transitions between the angular momentum states and magnetic states arising from polarized Stark fields as well as the system-bath interactions can be clearly observed in 2D rotational spectroscopy.

7.
J Vet Med Sci ; 81(9): 1355-1358, 2019 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-31316038

RESUMEN

To evaluate the preventive effects of combined vaccination for Pasteurella multocida, Mannheimia haemolytica and Histophilus somni on respiratory diseases in Japanese Black calves, 295 calves at one farm were alternately assigned to two groups; 147 calves received the vaccine at 4 and 8 weeks of age (vaccination group), and the other 148 calves did not receive vaccine (control group). The incidences of respiratory diseases were 25.9 and 70.9% in the vaccination and control groups, respectively, and the odds ratio for comparison between the two groups was 0.143 (95% confidence interval: 0.086-0.238). Administration of the multiple vaccine to Japanese black calves might be one of effective factor for prevention of respiratory diseases.


Asunto(s)
Enfermedades de los Bovinos/prevención & control , Mannheimia haemolytica/inmunología , Pasteurella multocida/inmunología , Pasteurellaceae/inmunología , Animales , Vacunas Bacterianas/administración & dosificación , Bovinos , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/microbiología , Enfermedades Respiratorias/inmunología , Enfermedades Respiratorias/prevención & control , Vacunación/veterinaria
8.
Sensors (Basel) ; 19(9)2019 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-31052311

RESUMEN

This paper presents a soft tactile sensor system for the localization of sliding movements on a large contact surface using an accelerometer. The system consists of a silicone rubber base with a chamber covered by a thin silicone skin in which a three-axis accelerometer is embedded. By pressurizing the chamber, the skin inflates, changing its sensitivity to the sliding movement on the skin's surface. Based on the output responses of the accelerometer, the sensor system localizes the sliding motion. First, we present the idea, design, fabrication process, and the operation principle of our proposed sensor. Next, we created a numerical simulation model to investigate the dynamic changes of the accelerometer's posture under sliding actions. Finally, experiments were conducted with various sliding conditions. By confirming the numerical simulation, dynamic analysis, and experimental results, we determined that the sensor system can detect the sliding movements, including the sliding directions, velocity, and localization of an object. We also point out the role of pressurization in the sensing system's sensitivity under sliding movements, implying the ideal pressurization for it. We also discuss its limitations and applicability. This paper reflects our developed research in intelligent integration and soft morphological computation for soft tactile sensing systems.

9.
Vet Sci ; 5(4)2018 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-30558176

RESUMEN

The purpose of this study was to determine the effect of vaccination and beta-carotene supplementation on blood oxidative stress and antibody response in calves. Thirty Japanese Black calves were randomly assigned to two groups. Fifteen calves received 20 mg of beta-carotene supplemented into their daily provided rations from 2 to 8 weeks of age (BC group), and the other 15 calves did not receive the daily beta-carotene supplement (control group). All calves received a commercially available modified live bovine respiratory syncytial (RS) virus vaccine at 4 and 8 weeks of age. Blood samples were taken at 2, 4, 8, and 12 weeks of age. At 4 weeks of age, the concentration of reactive oxygen metabolites within serum were significantly lower in the BC group than the concentrations measured in the control group. Also at 4 weeks of age, the concentration of biological antioxidant capacity within serum was significantly higher in the BC group than the concentrations measured in the control group. Both groups showed a gradual decrease of antibody titers to live bovine RS virus in the samples taken from 2 to 12 weeks of age. These results confirmed that beta-carotene supplementation decreased oxidative stress. However, beta-carotene supplementation did not affect the antibody response to live bovine RS virus vaccination, perhaps due to the presence of the maternal antibody.

10.
J Chem Phys ; 149(8): 084110, 2018 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-30193481

RESUMEN

We consider a two-dimensional rigid rotator system coupled to a two-dimensional heat bath. The Caldeira-Leggett (Brownian) model for the rotator and the spin-Boson model have been used to describe such systems, but they do not possess rotational symmetry, and they cannot describe the discretized rotational bands in absorption and emission spectra that have been found experimentally. Here, to address this problem, we introduce a rotationally invariant system-bath (RISB) model that is described by two sets of harmonic-oscillator baths independently coupled to the rigid rotator as sine and cosine functions of the rotator angle. Due to a difference in the energy discretization of the total Hamiltonian, the dynamics described by the RISB model differ significantly from those described by the rotational Caldeira-Legget model, while both models reduce to the Langevin equation for a rotator in the classical limit. To demonstrate this point, we compute the rotational absorption spectrum defined by the linear response function of a rotator dipole. For this purpose, we derive a quantum master equation for the RISB model in the high-temperature Markovian case. We find that the spectral profiles of the calculated signals exhibit a transition from quantized rotational bands to a single peak after spectrum collapse. This is a significant finding because previous approaches cannot describe such phenomena in a unified manner.

11.
Drug Metab Dispos ; 42(2): 229-38, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24255116

RESUMEN

Functional protein-protein interactions between UDP-glucuronosyltransferase (UGT)1A isoforms and cytochrome P450 (CYP)3A4 were studied. To this end, UGT1A-catalyzed glucuronidation was assayed in Sf-9 cells that simultaneously expressed UGT and CYP3A4. In the kinetics of UGT1A6-catalyzed glucuronidation of serotonin, both Michaelis constant (Km) and maximal velocity (Vmax) were increased by CYP3A4. When CYP3A4 was coexpressed with either UGT1A1 or 1A7, the Vmax for the glucuronidation of the irinotecan metabolite (SN-38) was significantly increased. S50 and Km both which are the substrate concentration giving 0.5 Vmax were little affected by simultaneous expression of CYP3A4. This study also examined the catalytic properties of the allelic variants of UGT1A1 and 1A7 and their effects on the interaction with CYP3A4. Although the UGT1A1-catalyzing activity of 4-methylumbelliferone glucuronidation was reduced in its variant, UGT1A1*6, the coexpression of CYP3A4 restored the impaired function to a level comparable with the wild type. Similarly, simultaneous expression of CYP3A4 increased the Vmax of UGT1A7*1 (wild type) and *2 (N129K and R131K), whereas the same was not observed in UGT1A7*3 (N129K, R131K, and W208R). In the kinetics involving different concentrations of UDP-glucuronic acid (UDP-GlcUA), the Km for UDP-GlcUA was significantly higher for UGT1A7*2 and *3 than *1. The Km of UGT1A7*1 and *3 was increased by CYP3A4, whereas *2 did not exhibit any such change. These results suggest that (1) CYP3A4 changes the catalytic function of the UGT1A subfamily in a UGT isoform-specific manner and (2) nonsynonymous mutations in UGT1A7*3 reduce not only the ability of UGT to use UDP-GlcUA but also CYP3A4-mediated enhancement of catalytic activity, whereas CYP3A4 is able to restore the UGT1A1*6 function.


Asunto(s)
Citocromo P-450 CYP3A/metabolismo , Glucurónidos/metabolismo , Glucuronosiltransferasa/metabolismo , Biotransformación , Camptotecina/análogos & derivados , Camptotecina/metabolismo , Catálisis , Citocromo P-450 CYP3A/genética , Glucuronosiltransferasa/genética , Humanos , Himecromona/metabolismo , Isoenzimas , Cinética , Mutación , Mapeo de Interacción de Proteínas , Serotonina/metabolismo , Células Sf9 , Especificidad por Sustrato , Transfección
12.
Neurosci Lett ; 505(3): 291-3, 2011 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-22051522

RESUMEN

In the absence of visual information, humans cannot maintain a straight walking path. We examined the hypothesis that step frequency during walking affects the magnitude of veering in healthy adults. Subject walked at a preferred (1.77 ± 0.18 Hz), low (0.8 × preferred, 1.41 ± 0.15 Hz), and high (1.2× preferred, 2.13 ± 0.20 Hz) step frequency with and without a blindfold. We compared the absolute differences between estimated and measured points of crossing a target line after 16 m of forward walking at the three step frequencies. There was no significant difference in veering when subjects walked at the different frequencies without a blindfold. However, the magnitude of veering was the smallest at the preferred (mean ± SE=91.6 ± 33.6 cm) compared with the low (204.3 ± 43.0 cm) and high (112.7 ± 34.0 cm) frequency gaits with a blindfold. Thus, walking at a preferred step frequency minimizes veering, which occurs in the absence of visual information. This phenomenon may be associated with the previously reported minimization of movement variability, energy cost, and attentional demand while walking at a preferred step frequency.


Asunto(s)
Marcha , Conducta Espacial/fisiología , Caminata , Humanos , Masculino , Desempeño Psicomotor , Percepción Espacial , Adulto Joven
13.
Artículo en Inglés | MEDLINE | ID: mdl-20693675

RESUMEN

The xylulose-5-phosphate/fructose-6-phosphate phosphoketolase gene from Bifidobacterium breve was cloned and overexpressed in Escherichia coli. The enzyme was purified to homogeneity and crystallized by the sitting-drop vapour-diffusion method. Crystals were obtained at 293 K using 0.05 mM thiamine diphosphate, 0.25 mM MgCl2, 24%(w/v) PEG 6000 and 0.1 M Bicine pH 9.0. The crystals belonged to the tetragonal space group I422, with unit-cell parameters a=b=174.8, c=163.8 A, and diffracted to beyond 1.7 A resolution.


Asunto(s)
Aldehído-Liasas/química , Bifidobacterium/enzimología , Aldehído-Liasas/genética , Cristalización , Cristalografía por Rayos X , Expresión Génica
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