Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 44
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Am J Pathol ; 194(1): 135-149, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37918800

RESUMEN

Osteophytes in osteoarthritis (OA) joints contribute to restriction of joint movement, joint pain, and OA progression, but little is known about osteophyte regulators. Examination of gene expression related to cartilage extracellular matrix, endochondral ossification, and growth factor signaling in articular cartilage and osteophytes obtained from OA knee joints showed that several genes such as COL1A1, VCAN, BGLAP, BMP8B, RUNX2, and SOST were overexpressed in osteophytes compared with articular cartilage. Ratios of mesenchymal stem/progenitor cells, which were characterized by co-expression of CD105 and CD166, were significantly higher in osteophytic cells than articular cells. A three-dimensional culture method for cartilage and osteophyte cells was developed by modification of cultures of self-assembled spheroid cell organoids (spheroids). These spheroids cultured in the media for mesenchymal stem cells containing transforming growth factor-ß3 showed characteristic morphologies and gene expression profiles of articular cartilage and osteophytes, respectively. The effects of IL-1ß, tumor necrosis factor-α, and IL-6 on the spheroids of articular and osteophytic cells were studied. To the best of our knowledge, they provide the first evidence that IL-6 suppresses the spheroid size of osteophytic cells by inducing apoptosis and reducing extracellular matrix molecules. These data show that IL-6 is the suppressor of osteophyte growth and suggest that IL-6 expression and/or activity are implicated in the regulation of osteophyte formation in pathologic joints.


Asunto(s)
Cartílago Articular , Osteoartritis de la Rodilla , Osteoartritis , Osteofito , Humanos , Cartílago Articular/patología , Condrocitos/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Interleucina-6/metabolismo , Articulación de la Rodilla/patología , Osteoartritis/patología , Osteoartritis de la Rodilla/metabolismo , Osteofito/genética , Osteofito/metabolismo , Osteofito/patología
2.
Phys Chem Chem Phys ; 25(8): 6203-6213, 2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36753064

RESUMEN

The nonionic surfactants Tween 80 (Tw80) and Triton X-100 (TX100), which are used as components of adjuvants, were used with bovine serum albumin (BSA) and hydroxfypropyl-ß-cyclodextrin (HP-ß-CD) as model antigens. The interaction patterns of Tw80 and TX100 with the hydrophobic cores of the model antigens were investigated. The fluorescence of 8-anilinonaphthalene-1-sulfonic acid (ANS), a hydrophobic fluorescent probe, was used to evaluate the effect of surfactants on each model antigen. A Hanes Woolf plot was used to analyze the adsorption of ANS to BSA, and an activator-inhibitor model was used to analyze the concentration-dependent increase and decrease of ANS fluorescence intensity. For BSA, TX100 occupies the ANS binding site inside the BSA hydrophobic core, while Tw80 does not contribute to the ANS binding site in the hydrophobic core. For HP-ß-CD, the ANS concentration required for analyzable fluorescence intensity extended to the range where ANS concentration-dependent quenching was not negligible. Using the activator inhibitor model, we were able to separate the activators and inhibitors of ANS fluorescence and evaluate the affinity of ANS for HP-ß-CD and surfactants. The results obtained showed that TX100 provided a hydrophobic environment to the ANS while being encapsulated by HP-ß-CD, while Tw80 did not interact with HP-ß-CD and provided a hydrophobic environment to the ANS independently of each other. The interpretations obtained were corroborated by the determination of the CMC of TX100 and Tw80, the effect of salt on ANS fluorescence, and 1H-NMR and ROESY. In summary, the results showed that the large hydrophilic head of Tween, composed of sorbitan and PEG chains, floated in the aqueous phase like a balloon, while Triton pierced the hydrophobic core of the antigen like a spear. In both BSA and HP-ß-CD model antigens, TX100 impinged on the hydrophobic core.


Asunto(s)
Adyuvantes de Vacunas , Polisorbatos , 2-Hidroxipropil-beta-Ciclodextrina , Octoxinol , Fluorescencia , Albúmina Sérica Bovina/química , Tensoactivos , Espectrometría de Fluorescencia/métodos
3.
Int J Mol Sci ; 24(4)2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36835365

RESUMEN

The nuclear receptor peroxisome proliferator-activated receptor α (PPARα) is a transcription factor that controls the transcription of genes responsible for fatty acid metabolism. We have recently reported a possible drug-drug interaction mechanism via the interaction of PPARα with the xenobiotic nuclear receptor constitutive androstane receptor (CAR). Drug-activated CAR competes with the transcriptional coactivator against PPARα and prevents PPARα-mediated lipid metabolism. In this study, to elucidate the crosstalk between CAR and PPARα, we focused on the influence of PPARα activation on CAR's gene expression and activation. Male C57BL/6N mice (8-12 weeks old, n = 4) were treated with PPARα and CAR activators (fenofibrate and phenobarbital, respectively), and hepatic mRNA levels were determined using quantitative reverse transcription PCR. Reporter assays using the mouse Car promoter were performed in HepG2 cells to determine the PPARα-dependent induction of CAR. CAR KO mice were treated with fenofibrate, and the hepatic mRNA levels of PPARα target genes were determined. Treatment of mice with a PPARα activator increased Car mRNA levels as well as genes related to fatty acid metabolism. In reporter assays, PPARα induced the promoter activity of the Car gene. Mutation of the putative PPARα-binding motif prevented PPARα-dependent induction of reporter activity. In electrophoresis mobility shift assay, PPARα bound to the DR1 motif of the Car promoter. Since CAR has been reported to attenuate PPARα-dependent transcription, CAR was considered a negative feedback protein for PPARα activation. Treatment with fenofibrate induced the mRNA levels of PPARα target genes in Car-null mice more than those in wild-type mice, suggesting that CAR functions as a negative feedback factor for PPARα.


Asunto(s)
Receptor de Androstano Constitutivo , Hígado , PPAR alfa , Animales , Masculino , Ratones , Receptor de Androstano Constitutivo/genética , Receptor de Androstano Constitutivo/metabolismo , Ácidos Grasos/metabolismo , Fenofibrato/farmacología , Hígado/metabolismo , Ratones Endogámicos C57BL , PPAR alfa/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , ARN Mensajero/metabolismo , Factores de Transcripción/metabolismo
4.
Chem Pharm Bull (Tokyo) ; 70(2): 120-129, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35110432

RESUMEN

Certain combinations of acidic and basic drugs can cause significant changes in physicochemical properties through the formation of ionic liquids, eutectic mixtures, or deep eutectic solvents. In particular, combining indomethacin and lidocaine is known to result in apparent increases in both the partition coefficients (hydrophobicity) and aqueous solubilities (hydrophilicity). The physicochemical interactions between drugs change the water solubility of the drugs and affect the bio-availability of active pharmaceutical ingredients. Therefore, we need to clarify the mechanism of changes of water solubility of drugs through the physicochemical interactions. In the present study, we identified a thermodynamic factor that regulates the dissolution of a basic drug, in the presence of various acidic nonsteroidal anti-inflammatory drugs. The results demonstrated that enthalpy-entropy compensation plays a key role in the dissolution of drug mixtures and that relevant thermodynamic conditions should be considered.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Diltiazem/química , Termodinámica , Estructura Molecular , Solubilidad , Agua/química
5.
J Plant Res ; 134(4): 811-819, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33839995

RESUMEN

Organisms have a variety of three-dimensional (3D) structures that change over time. These changes include twisting, which is 3D deformation that cannot happen in two dimensions. Twisting is linked to important adaptive functions of organs, such as adjusting the orientation of leaves and flowers in plants to align with environmental stimuli (e.g. light, gravity). Despite its importance, the underlying mechanism for twisting remains to be determined, partly because there is no rigorous method for quantifying the twisting of plant organs. Conventional studies have relied on approximate measurements of the twisting angle in 2D, with arbitrary choices of observation angle. Here, we present the first rigorous quantification of the 3D twisting angles of Arabidopsis petioles based on light sheet microscopy. Mathematical separation of bending and twisting with strict definition of petiole cross-sections were implemented; differences in the spatial distribution of bending and twisting were detected via the quantification of angles along the petiole. Based on the measured values, we discuss that minute degrees of differential growth can result in pronounced twisting in petioles.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Flores , Hojas de la Planta
6.
Mol Pharmacol ; 98(5): 634-647, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32892155

RESUMEN

Long-term administration of some antiepileptic drugs often increases blood lipid levels. In this study, we investigated its molecular mechanism by focusing on the nuclear receptors constitutive active/androstane receptor (CAR) and peroxisome proliferator-activated receptor α (PPARα), which are key transcription factors for enzyme induction and lipid metabolism, respectively, in the liver. Treatment of mice with the CAR activator phenobarbital, an antiepileptic drug, increased plasma triglyceride levels and decreased the hepatic expression of PPARα target genes related to lipid metabolism. The increase in PPARα target gene expression induced by fenofibrate, a PPARα ligand, was inhibited by cotreatment with phenobarbital. CAR suppressed PPARα-dependent gene transcription in HepG2 cells but not in COS-1 cells. The mRNA level of peroxisome proliferator-activated receptor γ coactivator 1α (PGC1α), a coactivator for both CAR and PPARα, in COS-1 cells was much lower than in HepG2 cells. In reporter assays with COS-1 cells overexpressing PGC1α, CAR suppressed PPARα-dependent gene transcription, depending on the coactivator-binding motif. In mammalian two-hybrid assays, CAR attenuated the interaction between PGC1α and PPARα Chemical inhibition of PGC1α prevented phenobarbital-dependent increases in plasma triglyceride levels and the inhibition of PPARα target gene expression. These results suggest that CAR inhibits the interaction between PPARα and PGC1α, attenuating PPARα-dependent lipid metabolism. This might explain the antiepileptic drug-induced elevation of blood triglyceride levels. SIGNIFICANCE STATEMENT: Constitutive active/androstane receptor activated by antiepileptic drugs inhibits the peroxisome proliferator-activated receptor α-dependent transcription of genes related to lipid metabolism and upregulates blood triglyceride levels. The molecular mechanism of this inhibition involves competition between these nuclear receptors for coactivator peroxisome proliferator-activated receptor γ coactivator-1α binding.


Asunto(s)
Anticonvulsivantes/farmacología , PPAR alfa/metabolismo , PPAR gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Triglicéridos/sangre , Animales , Línea Celular Tumoral , Receptor de Androstano Constitutivo , Inducción Enzimática/efectos de los fármacos , Fenofibrato/farmacología , Células Hep G2 , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Fenobarbital/farmacología , Factores de Transcripción/metabolismo , Activación Transcripcional/efectos de los fármacos
7.
Chem Pharm Bull (Tokyo) ; 67(4): 361-366, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30930440

RESUMEN

Dissolution kinetics of a bilayer direct compress tablet was evaluated by using degassing cyclic flow UV-visible (Vis) spectroscopy with chemometrics. The model bilayer nicotinamide (NA)-pyridoxine hydrochloride (PH) 100.0 mg tablets were prepared via the dual compress method. The fast diffusion layer of the bilayer tablet contained nicotinamide, microcrystal cellulose, beta-lactose, magnesium stearate, and croscarmellose sodium. The slow release layer contained pyridoxine hydrochloride and carnauba wax. The monolayer direct compress tablets were prepared as dual ingredient (API)s formulation tablets. The degassing cyclic flow UV-Vis spectroscopy dissolution test was carried out using the prepared tablets. The dissolution test conditions were as follows: time, 60 min; temperature, 37°C; paddle method, 50 rpm, and UV-Vis spectra measurement 1 time/min. The UV-Vis spectra of the flow solution were measured in the range of 240-380 nm. API concentration was predicted by partial least squares (PLS) regression models based on UV-Vis spectra. The dissolution kinetics of the bilayer and monolayer tablets were evaluated based on the UV-Vis spectra with the predicted API concentration profile. The degassing flow system could prevent air bubbles in the flow cell at 1800 min. Therefore, simultaneous determination of NA and PH concentration based on the PLS regression was suggested to have high accuracy. PLS regression has advantages over the conventional λmax absorbance method of simultaneous determination. We found that the kinetics of the separated bilayer tablet can be evaluated by the same kinetic analysis method used for the single layer model tablet.


Asunto(s)
Modelos Químicos , Comprimidos/química , Composición de Medicamentos , Liberación de Fármacos , Concentración de Iones de Hidrógeno , Cinética , Análisis de los Mínimos Cuadrados , Niacinamida/química , Piridoxina/química , Solubilidad , Espectrofotometría , Comprimidos/metabolismo , Temperatura
8.
Nucleic Acids Res ; 43(Database issue): D606-17, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25399415

RESUMEN

Comprehensive experimental resources, such as ORFeome clone libraries and deletion mutant collections, are fundamental tools for elucidation of gene function. Data sets by omics analysis using these resources provide key information for functional analysis, modeling and simulation both in individual and systematic approaches. With the long-term goal of complete understanding of a cell, we have over the past decade created a variety of clone and mutant sets for functional genomics studies of Escherichia coli K-12. We have made these experimental resources freely available to the academic community worldwide. Accordingly, these resources have now been used in numerous investigations of a multitude of cell processes. Quality control is extremely important for evaluating results generated by these resources. Because the annotation has been changed since 2005, which we originally used for the construction, we have updated these genomic resources accordingly. Here, we describe GenoBase (http://ecoli.naist.jp/GB/), which contains key information about comprehensive experimental resources of E. coli K-12, their quality control and several omics data sets generated using these resources.


Asunto(s)
Bases de Datos Genéticas , Escherichia coli K12/genética , Proteínas de Escherichia coli/metabolismo , Genes Bacterianos , Genoma Bacteriano , Internet , Anotación de Secuencia Molecular , Mutación
10.
Chem Pharm Bull (Tokyo) ; 64(8): 1129-35, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27477651

RESUMEN

We propose an approach for the simultaneous determination of multiple components in pharmaceutical mixed powder based on powder X-ray diffraction (PXRD) method coupled with chemometrics. Caffeine anhydrate, acetaminophen and lactose monohydrate were mixed at various ratios. The samples were analyzed by PXRD method in the ranges of 2θ=5.00-30.0 and 35.0-45.0 degrees. Obtained diffractograms were analyzed by conventional peak intensity method, multi curve resolution (MCR)-alternating least squares (ALS) method and partial least squares (PLS) method. Constructed PLS models can most accurately predict the concentrations among different methods used. Each regression vector of PLS correlates not only to the compound of interest but also to the coexisting compounds. The combination of PXRD and PLS methods is concluded to be powerful approach for analyzing multi components in pharmaceutical formulations.


Asunto(s)
Acetaminofén/análisis , Acetaminofén/química , Cafeína/análisis , Cafeína/química , Lactosa/análisis , Lactosa/química , Difracción de Polvo , Polvos
11.
Adv Exp Med Biol ; 883: 155-68, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26621467

RESUMEN

E. coli has been a critically important model research organism for more than 50 years, particularly in molecular biology. In 1997, the E. coli draft genome sequence was published. Post-genomic techniques and resources were then developed that allowed E. coli to become a model organism for systems biology. Progress made since publication of the E. coli genome sequence will be summarized.


Asunto(s)
Biología Computacional , Escherichia coli/genética , Biblioteca de Genes , Ensayos Analíticos de Alto Rendimiento
12.
Biomed Mater Eng ; 35(1): 77-85, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37424460

RESUMEN

BACKGROUND: Cerium ions promote osteoclastogenesis and activate bone metabolism, while cerium oxide nanoparticles exhibit potent anti-inflammatory properties, making them promising for biomedical applications. OBJECTIVE: The purpose of this study was to develop and evaluate a synthesis method for sustained-release cerium-ion bioceramics containing apatite. Substituted apatite was found to be an effective biomaterial. METHODS: Cerium-containing chlorapatite was synthesized using a mechanochemical method employing dicalcium phosphate, cerium chloride heptahydrate, and calcium hydroxide as raw materials. The synthesized samples were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Raman spectroscopy. RESULTS: Cerium chlorapatite was successfully synthesized in the 10.1% and 20.1% samples. However, at Ce concentrations higher than 30.2%, the samples consisted of three or more phases, indicating the instability of a single phase. CONCLUSION: The method used in this study was found to be more efficient and cost-effective than the precipitation method for producing substituted apatite and calcium phosphate-based biomaterials. This research contributes to the development of sustained-release cerium-ion bioceramics with potential applications in the field of biomedicine.


Asunto(s)
Hidróxido de Calcio , Cerio , Cloruros , Preparaciones de Acción Retardada , Fosfatos de Calcio/química , Apatitas/química , Materiales Biocompatibles/química , Espectroscopía Infrarroja por Transformada de Fourier , Cerio/química , Difracción de Rayos X
13.
Biomed Mater Eng ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38848165

RESUMEN

BACKGROUND: Research using panoramic X-ray images using deep learning has been progressing in recent years. There is a need to propose methods that can classify and predict from image information. OBJECTIVE: In this study, Eichner classification was performed on image processing based on panoramic X-ray images. The Eichner classification was based on the remaining teeth, with the aim of making partial dentures. This classification was based on the condition that the occlusal position was supported by the remaining teeth in the upper and lower jaws. METHODS: Classification models were constructed using two convolutional neural network methods: the sequential and VGG19 models. The accuracy was compared with the accuracy of Eichner classification using the sequential and VGG19 models. RESULTS: Both accuracies were greater than 81%, and they had sufficient functions for the Eichner classification. CONCLUSION: We were able to build a highly accurate prediction model using deep learning scratch sequential model and VGG19. This predictive model will become part of the basic considerations for future AI research in dentistry.

14.
Osteoarthr Cartil Open ; 6(2): 100454, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38469555

RESUMEN

Objective: Considering the joint space width and osteophyte area (OPA) of the knee joints of Japanese adults, this study elucidated the ten-year trends in medial minimum joint space width (mJSW) and OPA using data of two independent cohorts from a population-based cohort study. Methods: The baseline survey of the Research on Osteoarthritis/Osteoporosis Against Disability study was conducted from 2005 to 2007; 2975 participants (1041 men, 1934 women) completed all knee osteoarthritis (OA) examinations. The fourth survey was performed from 2015 to 2016; distinct 2445 participants (764 men, 1681 women) completed identical examinations. The medial mJSW and medial tibial OPA were measured bilaterally using an automated system. Results: The mean medial mJSW (standard deviation) was 3.22 (0.96) mm and 2.65 (0.95) mm at baseline and 3.81 (1.20) mm and 3.13 (1.15) mm in the fourth survey for men and women, respectively. The mean medial mJSW in the fourth survey was significantly greater in both men and women in all age groups than at baseline (p â€‹< â€‹0.01). The mean OPAs in men aged 40-49 and 60-69 years and women aged 40-49, 50-59, 60-69, and 70-79 years were significantly smaller in the fourth survey (p â€‹< â€‹0.05). The trend in mJSW remained the same even after adjusting for confounding factors in the multivariate analysis, but the trend in OPA was weakened. Conclusions: A significant improvement in the medial mJSW within 10 years could decrease the incidence and progression of knee OA and prevent the risk of walking disability.

15.
J Pharm Sci ; 111(1): 88-94, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34139260

RESUMEN

The purpose of this study is to investigate the effects of dry and wet mechanochemical synthesis on piroxicam (PX) and saccharin (SA) mixtures. For this purpose, PX and SA mixtures prepared by wet mechanochemical processes using three solvents and by dry mechanochemical synthesis were evaluated by mid-and near-infrared spectroscopy, powder X-ray diffraction (PXRD), and differential scanning calorimetry (DSC). The mixtures of wet-type products were transformed into PX/SA 1:1 co-crystals. The effect of the solvent was key to the co-crystallization of PX and SA. The products from the dry process were transformed into the amorphous phase. For the sample of the amorphous mixture, two exothermic peaks due to crystallization were observed in the thermal analysis. Bulk PX was ground for the same number of times for transformation, but was not successfully transformed to the amorphous bulk; the same was observed for SA. It is suggested that the mutual existence of PX and SA promotes mutual amorphization.


Asunto(s)
Piroxicam , Sacarina , Rastreo Diferencial de Calorimetría , Piroxicam/química , Difracción de Polvo , Polvos , Sacarina/química , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Espectroscopía Infrarroja Corta , Difracción de Rayos X
16.
Biomed Mater Eng ; 33(3): 183-194, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34897077

RESUMEN

BACKGROUND: Control of the pharmaceutical manufacturing process and active pharmaceutical ingredients (API) is essential to product formulation and bioavailability. OBJECTIVE: The aim of this study is to predict tablet surface API concentration by chemometrics using integrating sphere UV-Vis spectroscopy, a non-destructive and contact-free measurement method. METHODS: Riboflavin, pyridoxine hydrochloride, dicalcium phosphate anhydrate, and magnesium stearate were mixed and ground with a mortar and pestle, and 100 mg samples were subjected to direct compression at a compaction pressure of 6 MPa at 7 mm diameter. The flat surface tablets were then analyzed by integrating sphere UV-Vis spectrometry. Standard normal variate (SNV) normalization and principal component analysis were applied to evaluate the measured spectral dataset. The spectral ranges were prepared at 300-800 nm and 500-700 nm with SNV normalization. Partial least squares (PLS) regression models were constructed to predict the API concentrations based on two previous datasets. RESULTS: The regression vector of constructed PLS regression models for each API was evaluated. API concentration prediction depends on riboflavin absorbance at 550 nm and the excipient dicalcium phosphate anhydrate. CONCLUSION: Integrating sphere UV-Vis spectrometry is a useful tool to process analytical technology.


Asunto(s)
Quimiometría , Riboflavina , Análisis de los Mínimos Cuadrados , Análisis Espectral/métodos , Comprimidos/química , Tecnología Farmacéutica/métodos
17.
Colloids Surf B Biointerfaces ; 212: 112344, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35101827

RESUMEN

In the present study, we investigated the effect of bile salts (sodium deoxycholate, NaDC) on the conformation of a globular protein (bovine serum albumin, BSA). The two Tryptophan (Trp) residues of BSA and the fluorescence energy of NaDC are in a three-way relationship, and singular value decomposition (SVD) was used to separate each element in the fluorescence spectra. SVD was used to separate the elements in the fluorescence spectra. SVD showed that NaDC had a particularly large effect on the microenvironment around Trp213 and that micellar NaDC enhanced the selectivity for Trp213. In addition, the Stern-Volmer plots of the warfarin (WAR) specific domain (domain I) and ketoprofen (KP) specific domain (domain II) in the presence and absence of NaDC showed that the effect of NaDC was selective for domain II, where Trp213 is located. These results indicate that NaDC induces a localized and selective conformational change in BSA, and that the selectivity varies depending on the aggregation state of NaDC.


Asunto(s)
Ácido Desoxicólico , Albúmina Sérica Bovina , Ácidos y Sales Biliares , Ácido Desoxicólico/química , Ácido Desoxicólico/farmacología , Micelas , Albúmina Sérica Bovina/química , Espectrometría de Fluorescencia , Triptófano/química
18.
RSC Adv ; 12(4): 1914-1921, 2022 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-35425255

RESUMEN

Polytetrafluoroethylene (PTFE) has excellent physical properties and has been used in a wide range of applications in various fields. Adsorption research on PTFE is essential as primary research for the further application of PTFE. We attempted to adsorb coal tar dyes and model drugs such as lidocaine onto PTFE as a guideline to search for medicines that adsorb onto PTFE. Saturation curves were obtained after analyzing the adsorption of coal tar dyes on PTFE using the Hanes-Woolf plot. In addition, we collected multiple cases of ATR-FTIR spectral changes and/or retention depending on TPM derivatives and other adsorbates. Lidocaine matched some coal tar dye for the apparent spectral changes between the adsorbed molecules and its crystalline powder. The apparent spectral changes are blue-shifted, suggesting a hydrophobic interaction between the dyes/lidocaine and porous PTFE. This work provides a promising strategy for further application of PTFE.

19.
Elife ; 112022 08 09.
Artículo en Inglés | MEDLINE | ID: mdl-35942683

RESUMEN

Secreted molecules called morphogens govern tissue patterning in a concentration-dependent manner. However, it is still unclear how reproducible patterning can be achieved with diffusing molecules, especially when that patterning concerns differentiation of thin tissues. Wnt is a morphogen that organizes cardiac development. Wnt6 patterns cardiogenic mesoderm to induce differentiation of a thin tissue, the pericardium, in Xenopus. In this study, we revealed that a Wnt receptor, frizzled-7, is expressed in a Wnt-dependent manner. With a combination of experiments and mathematical modeling, this receptor-feedback appears essential to shape a steep gradient of Wnt signaling. In addition, computer simulation revealed that this feedback imparts robustness against variations of Wnt ligand production and allows the system to reach a steady state quickly. We also found that a Wnt antagonist sFRP1, which is expressed on the opposite side of the Wnt source, accumulates on N-acetyl-rich heparan sulfate (HS). N-acetyl-rich HS concentration is high between the sources of Wnt and sFRP1, achieving local inhibition of Wnt signaling via restriction of sFRP1 spreading. These integrated regulatory systems restrict the Wnt signaling range and ensure reproducible patterning of the thin pericardium.


Asunto(s)
Heparitina Sulfato , Vía de Señalización Wnt , Animales , Simulación por Computador , Retroalimentación , Xenopus laevis
20.
Front Nutr ; 9: 912217, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35873410

RESUMEN

Objective: Aging of skeletal muscle is characterized not only by a decrease of muscle quantity but also by changes in muscle quality, such as an increase in muscle stiffness. The present study aimed to investigate the effects of supplementation with quercetin glycosides (QGs), well-known polyphenolic flavonoids, combined with resistance exercise on muscle quantity and stiffness. Materials and Methods: A randomized, controlled trial was conducted in community-dwelling, Japanese people aged 50-74 years who were randomly allocated to exercise with placebo or 200 or 500 mg of QG supplementation. All participants performed low-intensity resistance training mainly targeting thigh muscles with 40% of 1-repetition maximum, 3 days per week for 24 weeks. Muscle cross-sectional area (CSA), lean mass, and vastus lateralis (VL) muscle stiffness were measured before and after the 24-week intervention. Results: Forty-eight subjects completed the 24-week intervention. There were no significant group × time interactions in thigh CSA for primary outcome, as well as lean mass. VL muscle stiffness in the stretched position was significantly lower in both the 200 mg and 500 mg QG groups than in the placebo group after the 24-week intervention (p < 0.05). No significant correlation was observed between changes of VL muscle CSA and stiffness during the 24-week intervention. Conclusion: Quercetin glycoside supplementation combined with low-intensity resistance exercise improved passive muscle stiffness independently of muscle quantity. Clinical Trial Registration: [www.umin.ac.jp/ctr/], identifier [UMIN000037633].

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA