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1.
Psychol Med ; : 1-14, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38500410

RESUMEN

BACKGROUND: Previous research on the changes in resting-state functional connectivity (rsFC) in anorexia nervosa (AN) has been limited by an insufficient sample size, which reduced the reliability of the results and made it difficult to set the whole brain as regions of interest (ROIs). METHODS: We analyzed functional magnetic resonance imaging data from 114 female AN patients and 135 healthy controls (HC) and obtained self-reported psychological scales, including eating disorder examination questionnaire 6.0. One hundred sixty-four cortical, subcortical, cerebellar, and network parcellation regions were considered as ROIs. We calculated the ROI-to-ROI rsFCs and performed group comparisons. RESULTS: Compared to HC, AN patients showed 12 stronger rsFCs mainly in regions containing dorsolateral prefrontal cortex (DLPFC), and 33 weaker rsFCs primarily in regions containing cerebellum, within temporal lobe, between posterior fusiform cortex and lateral part of visual network, and between anterior cingulate cortex (ACC) and thalamus (p < 0.01, false discovery rate [FDR] correction). Comparisons between AN subtypes showed that there were stronger rsFCs between right lingual gyrus and right supracalcarine cortex and between left temporal occipital fusiform cortex and medial part of visual network in the restricting type compared to the binge/purging type (p < 0.01, FDR correction). CONCLUSION: Stronger rsFCs in regions containing mainly DLPFC, and weaker rsFCs in regions containing primarily cerebellum, within temporal lobe, between posterior fusiform cortex and lateral part of visual network, and between ACC and thalamus, may represent categorical diagnostic markers discriminating AN patients from HC.

2.
Mol Psychiatry ; 29(4): 891-901, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38246936

RESUMEN

Although brain morphological abnormalities have been reported in anorexia nervosa (AN), the reliability and reproducibility of previous studies were limited due to insufficient sample sizes, which prevented exploratory analysis of the whole brain as opposed to regions of interest (ROIs). Objective was to identify brain morphological abnormalities in AN and the association with severity of AN by brain structural magnetic resonance imaging (MRI) in a multicenter study, and to conduct exploratory analysis of the whole brain. Here, we conducted a cross-sectional multicenter study using T1-weighted imaging (T1WI) data collected between May 2014 and February 2019 in Japan. We analyzed MRI data from 103 female AN patients (58 anorexia nervosa restricting type [ANR] and 45 anorexia nervosa binge-purging type [ANBP]) and 102 age-matched female healthy controls (HC). MRI data from five centers were preprocessed using the latest harmonization method to correct for intercenter differences. Gray matter volume (GMV) was calculated from T1WI data of all participants. Of the 205 participants, we obtained severity of eating disorder symptom scores from 179 participants, including 87 in the AN group (51 ANR, 36 ANBP) and 92 HC using the Eating Disorder Examination Questionnaire (EDE-Q) 6.0. GMV reduction were observed in the AN brain, including the bilateral cerebellum, middle and posterior cingulate gyrus, supplementary motor cortex, precentral gyrus medial segment, and thalamus. In addition, the orbitofrontal cortex (OFC), ventromedial prefrontal cortex (vmPFC), rostral anterior cingulate cortex (ACC), and posterior insula volumes showed positive correlations with severity of symptoms. This multicenter study was conducted with a large sample size to identify brain morphological abnormalities in AN. The findings provide a better understanding of the pathogenesis of AN and have potential for the development of brain imaging biomarkers of AN. Trial Registration: UMIN000017456. https://center6.umin.ac.jp/cgi-open-bin/icdr/ctr_view.cgi?recptno=R000019303 .


Asunto(s)
Anorexia Nerviosa , Sustancia Gris , Corteza Insular , Imagen por Resonancia Magnética , Neuroimagen , Corteza Prefrontal , Humanos , Femenino , Anorexia Nerviosa/patología , Anorexia Nerviosa/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Sustancia Gris/patología , Sustancia Gris/diagnóstico por imagen , Adulto , Estudios Transversales , Adulto Joven , Neuroimagen/métodos , Corteza Prefrontal/patología , Corteza Prefrontal/diagnóstico por imagen , Corteza Insular/diagnóstico por imagen , Corteza Insular/patología , Adolescente , Japón , Encéfalo/patología , Encéfalo/diagnóstico por imagen , Reproducibilidad de los Resultados
3.
J Toxicol Sci ; 48(10): 557-569, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37778984

RESUMEN

The hydrophilic compound 2-hydroxyethyl methacrylate (HEMA) is a major component of dental bonding materials, and it enhances the binding of resin-composites to biomolecules. However, HEMA is a well-known contact sensitizer. We reported previously that intradermal injection of HEMA induces the production of IL-1 locally in the skin. Keratinocytes are the first barrier against chemical insults and constitutively express IL-1α. In this study, we analyzed whether HEMA induces the production of inflammatory cytokines from murine keratinocyte cell line Pam212 cells. We demonstrated that HEMA induced the release of 17-kDa mature IL-1α and caused cytotoxicity. The activity of calpain, an IL-1α processing enzyme, was significantly higher in HEMA-treated cells. The thiol-containing antioxidant N-acetyl cysteine (NAC) inhibited HEMA-induced IL-1α release but not cytotoxicity. NAC inhibited intracellular calpain activity and reactive oxygen species (ROS) production induced by HEMA. NAC post-treatment also inhibited IL-1α release and intracellular ROS production induced by HEMA. Furthermore, HEMA-induced in vivo inflammation also inhibited by NAC. NAC inhibited polymerization of HEMA through adduct formation via sulfide bonds between the thiol group of NAC and the reactive double bond of HEMA. HEMA-induced IL-1α release and cytotoxicity were also inhibited if HEMA and NAC were pre-incubated before adding to the cells. These results suggested that NAC inhibited IL-1α release through decreases in intracellular ROS and the adduct formation with HEMA. We concluded that HEMA induces IL-1α release from skin keratinocytes, and NAC may be a promising candidate as a therapeutic agent against inflammation induced by HEMA.


Asunto(s)
Acetilcisteína , Calpaína , Ratones , Animales , Acetilcisteína/farmacología , Especies Reactivas de Oxígeno/metabolismo , Metacrilatos/toxicidad , Metacrilatos/química , Queratinocitos/metabolismo , Inflamación
4.
J Funct Biomater ; 13(4)2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36547524

RESUMEN

Titanium has excellent biocompatibility and good corrosion resistance and is extensively used in dental implants and denture bases. However, pure titanium lacks the strength for use in dental prostheses that require relatively high strength. We developed 15 different types of Ti-Nb-Cu alloys and investigated their alloy phases and mechanical properties, including tensile and yield strength, elongation after fracture, and Vickers hardness. The alloy phases of Ti-8%Nb-2%Cu and Ti-13%Nb-2%Cu were α + ß, while those of Ti-5%Nb-5%Cu and Ti-10%Nb-5%Cu were α + Ti2Cu. The tensile strength and hardness of these alloys were significantly higher than those of titanium; however, their elongation was less. In particular, the yield strength of these alloys was more than twice that of titanium. These differences in mechanical properties are attributable to solid-solution strengthening and precipitation strengthening. Other compositions with an alloy phase of α + ß + Ti2Cu or ß + Ti2Cu had high hardness but not high strength. These results suggest that the Ti-8%Nb-2%Cu, Ti-5%Nb-5%Cu, Ti-13%Nb-2%Cu, and Ti-10%Nb-5%Cu alloys can be applied to dental prostheses, which are subject to very high forces from accessories such as long-span bridges, clasps, implant-retained superstructures, and narrow-diameter implants.

5.
Materials (Basel) ; 15(24)2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36556817

RESUMEN

Titanium-20 mass% Silver (Ti-20%Ag) alloy can suppress biofilm formation on the surface. Unlike bactericidal agents, it does not kill bacteria; therefore, the healthy oral microflora remains undisturbed. To utilize the unique functions of this alloy and enable its use in the fabrication of dental prostheses that require relatively high strength, we added copper (Cu) as an alloying element to improve strength. This study aimed to develop ternary Ti-Ag-Cu alloys with excellent mechanical properties and antibiofilm activity. As a result of investigating the mechanical properties of several experimental alloys, the tensile strength, yield strength, and hardness of Ti-20%Ag-1%Cu and Ti-20%Ag-2%Cu alloys were improved by the solid-solution strengthening or hardening of the αTi phase. In addition, these alloys had the same ability to suppress biofilm formation as the Ti-20Ag alloy. Thus, Ti-20%Ag-1-2%Cu alloys can be used for fabrication of narrow-diameter dental implants and prostheses subjected to extremely high force, and these prostheses are useful in preventing post-treatment oral diseases.

6.
Heliyon ; 8(8): e10361, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36060989

RESUMEN

Two oval sandwich type magnetic attachments set up in various angulations and spacing, then the pattern of retentive force against horizontal displacement studied. A measuring device and methodology that matches ISO 13017 was used. A pair of magnetic attachments fixed on the same plane at a specific distance on the measuring device and set in various angulations. Retentive force readings of magnetic attachments in various setup positions against the horizontal displacement along the major or minor axis directions were taken. The pattern of decline in retentive force as horizontal displacement increased was different across the various set-ups. It was found that the decrease in retentive forces associated with horizontal displacement can be suppressed when the angle between the major axis and the direction of movement is as small as possible. Formation of a 90° angle between major axes of any pair of magnetic attachments led to nullification of the decline in retentive forces associated with displacement in any direction. Therefore, 90° is the practical, ideal set-up angle between any pair of dental magnetic attachments critical for suppression of the loss in retentive force associated with horizontal gap.

7.
J Oral Sci ; 64(3): 242-246, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35691887

RESUMEN

PURPOSE: Moisture exclusion while treating dental caries can be challenging, and the glass ionomer cements (GICs) used for these procedures are susceptible to water. Few studies have examined the effects of the powder/liquid ratio (PLR) on the physical properties of GICs exposed to water. In this study, the hardness and thickness of the water-susceptible surface layer of three GICs were evaluated. METHODS: Three conventional GICs were mixed in increasing PLRs, and hardness over time was measured under conditions of no water exposure, distilled water exposure, and saliva exposure. Furthermore, the thickness of the water-susceptible layer for each GIC was determined. RESULTS: A water-susceptible layer of approximately 250 µm was evident for all GICs, and the thickness decreased with increasing PLR. GIC hardness increased with increasing PLR in conditions without water for all GIC types. Furthermore, the removal of the water-susceptible layer restored the physical properties of each GIC. CONCLUSION: Overall, the results indicate that conventional GIC restoration with the removal of the water-susceptible surface layer is a feasible strategy for treating dental caries in individuals for whom exclusion of moisture can be difficult.


Asunto(s)
Caries Dental , Cementos de Ionómero Vítreo , Dureza , Humanos , Ensayo de Materiales
8.
Dent Mater J ; 41(4): 527-533, 2022 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-35264543

RESUMEN

The aim of this study was to assess the utility of an actuator-driven pulsed water jet (ADPJ) as a hardness-dependent carious dentin removal device by using different outputs. Thirty-six plane surface dental caries samples were treated with the ADPJ at 150, 200, and 250 voltage (12 teeth each). The Knoop hardness number (KHN) and Ca/P mass ratio were measured at 70 µm from the deepest point of the removing groove. Furthermore, three other teeth samples were manually treated with the ADPJ at the three above mentioned voltages (one tooth each) for 1 min. The KHN and Ca/P mass ratio were measured at 70 µm from the surface of the residual dentin part. In both the KHN and Ca/P mass ratio, higher residual dentin depended on the applied voltage of ADPJ. The ADPJ enabled the removal of softened carious dentin in an applied voltage-dependent manner.


Asunto(s)
Caries Dental , Caries Dental/terapia , Dentina , Dureza , Humanos , Agua
9.
Neuropathology ; 41(2): 118-126, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33415820

RESUMEN

We here report an autopsy case of familial amyotrophic lateral sclerosis (ALS) with p.Arg487His mutation in the valosin-containing protein (VCP) gene (VCP), in which upper motor neurons (UMNs) were predominantly involved. Moreover, our patient developed symptoms of frontotemporal dementia later in life and pathologically exhibited numerous phosphorylated transactivation response DNA-binding protein of 43 kDa (p-TDP-43)-positive neuronal cytoplasmic inclusions and short dystrophic neurites with a few lentiform neuronal intranuclear inclusions, sharing the features of frontotemporal lobar degeneration with TDP-43 pathology type A pattern. A review of previous reports of ALS with VCP mutations suggests that our case is unique in terms of its UMN-predominant lesion pattern and distribution of p-TDP-43 pathology. Thus, this case report effectively expands the clinical and pathological phenotype of ALS in patients with a VCP mutation.


Asunto(s)
Esclerosis Amiotrófica Lateral/metabolismo , Esclerosis Amiotrófica Lateral/patología , Autopsia , Mutación/genética , Proteinopatías TDP-43/metabolismo , Proteína que Contiene Valosina/genética , Autopsia/métodos , Proteínas de Unión al ADN/metabolismo , Degeneración Lobar Frontotemporal/metabolismo , Degeneración Lobar Frontotemporal/patología , Humanos , Cuerpos de Inclusión Intranucleares/metabolismo , Masculino , Persona de Mediana Edad , Neuronas Motoras/patología , Proteína que Contiene Valosina/metabolismo
10.
Dent Mater J ; 40(1): 8-15, 2021 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-32779604

RESUMEN

To characterize concentrated growth factors (CGFs) in vivo, we examined the degradation of implanted CGF in rabbits. Untreated CGF (U-CGF) and compressed CGF (C-CGF) were subcutaneously implanted into the dorsum. Histological analyses showed that the U-CGF and C-CGF induced very few inflammatory cells and that the U-CGF and C-CGF were subsequently degraded with dendritic invasion of granulation tissue. The C-CGF histopathologically remained for longer term than the U-CGF. Aggregated CD31+ and RAM11+ cells appeared in and around the implanted CGF. The number of macrophages and blood vessels in the CGF-implanted groups was greater than that in the sham group. There were more blood vessels in the U-CGF group than that in the C-CGF and sham group. We showed that CGF was degraded by macrophages in 4 weeks and enhanced angiogenesis with dendritically branching new capillaries. Therefore, the U-CGF and C-CGF can be clinically applied as a biomaterial inducing angiogenesis.


Asunto(s)
Materiales Biocompatibles , Péptidos y Proteínas de Señalización Intercelular , Animales , Conejos
11.
Dent Mater J ; 40(1): 61-67, 2021 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-32848101

RESUMEN

Binary Ti-Fe alloys of varying concentrations of Fe between 5-25% were made, and their castings evaluated in terms of microstructures formed and mechanical properties. The aim of this study was to explore the composition of Ti-Fe alloys that offers improved wear resistance of titanium. X-ray diffraction and microstructural observation revealed that 5-7% Fe, 8-15% Fe, and 20-25% Fe consisted of α+ß, single ß, and ß+Ti-Fe phases, respectively. The hardness of alloys with 8-13% Fe was almost equal to that of Co-Cr alloys but lower than of the other Ti-Fe alloys. Elongation of the Ti-Fe alloys was negligible. However, dimples were observed in specimen containing 7-11% Fe. Alloys with 9% Fe demonstrated the highest strength of more than 850 MPa. We believe that Ti-Fe alloys with 8-11% Fe may be applicable in development of an alloy with good wear resistance due to the exhibited properties of high hardness and ductility albeit low.


Asunto(s)
Aleaciones , Titanio , Aleaciones Dentales , Dureza , Ensayo de Materiales , Resistencia a la Tracción , Difracción de Rayos X
12.
Dent Mater J ; 40(1): 68-73, 2021 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-32848102

RESUMEN

Binary Ti-Fe alloys with 5-25 mass% Fe were prepared, and subjected to reciprocating wear test. The aim of this study was to investigate the relationship between mechanical properties and the wear resistance of titanium and Ti-Fe alloys. The dimensions (length, width and depth) of wear marks on Ti-Fe alloys were less than those observed on pure Ti specimen. Wear resistance of Ti-Fe alloys was better than that of pure titanium. It was established that hardness was the main factor that influenced wear resistance of Ti-Fe alloys. Single ß Ti-Fe alloys showed better wear resistance than α+ß Ti-Fe alloys. Increase in concentration of Fe in the ß phase of Ti-Fe alloys leads to improved wear resistance of the alloy. Ti-Fe alloys with 11-15 mass% Fe form ideal candidates for fabrication of dental titanium alloys with excellent wear resistance.


Asunto(s)
Aleaciones Dentales , Titanio , Aleaciones , Dureza , Ensayo de Materiales
13.
Sci Rep ; 10(1): 8553, 2020 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-32444858

RESUMEN

This study investigated the bactericidal effect, the underlying mechanisms of treatment, and recovery of biocompatibility of the infected titanium surface using a combination treatment of silver ion application and ultraviolet-A (UV-A) light irradiation. Streptococcus mutans and Aggregatibacter actinomycetemcomitans were used in suspension and as a biofilm on a titanium surface to test for the bactericidal effect. The bactericidal effect of the combination treatment was significantly higher than that of silver ion application or UV-A light irradiation alone. The bactericidal effect of the combination treatment was attributable to hydroxyl radicals, which generated from the bacterial cell wall and whose yield increased with the silver concentration. To assess the biocompatibility, proliferation and calcification of MC3T3E1 cells were evaluated on the treated titanium surface. The treated titanium screws were implanted into rat tibias and the removal torques were measured 28 days post-surgery. The titanium surface that underwent the combination treatment exhibited recovery of biocompatibility by allowing cellular proliferation or calcification at levels observed in the non-infected titanium surfaces. The removal torque 28 days after surgery was also comparable to the control values. This approach is a novel treatment option for peri-implantitis.


Asunto(s)
Aggregatibacter actinomycetemcomitans/crecimiento & desarrollo , Antibacterianos/administración & dosificación , Biopelículas/crecimiento & desarrollo , Radical Hidroxilo/química , Infecciones por Pasteurellaceae/prevención & control , Plata/administración & dosificación , Streptococcus mutans/crecimiento & desarrollo , Titanio/química , Aggregatibacter actinomycetemcomitans/efectos de los fármacos , Aggregatibacter actinomycetemcomitans/efectos de la radiación , Animales , Antibacterianos/química , Biopelículas/efectos de los fármacos , Biopelículas/efectos de la radiación , Ratones , Infecciones por Pasteurellaceae/microbiología , Periimplantitis/microbiología , Periimplantitis/terapia , Ratas , Ratas Wistar , Plata/química , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/efectos de la radiación , Tibia/microbiología , Tibia/cirugía , Rayos Ultravioleta
14.
Dent Mater J ; 39(3): 509-516, 2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-32115489

RESUMEN

This study explored modification of an alkaline heat treated titanium surface, using magnesium ions, to improve bone compatibility through the sustained release of magnesium ions. Pure titanium surface was first subjected to alkaline treatment using 5 M NaOH then modified with magnesium through immersion in magnesium chloride solution before heating in a furnace at 600°C for 1 h. Use of at least 0.01 M magnesium chloride solution for at least 0.5 min, leads to introduction of 1.7 to 2.3 at% magnesium at a distribution close to saturation on the titanium surface. The modified titanium surface sustained long term release of magnesium ions in acidic solution for more than 168 h. It was further demonstrated that the process of sustained release of magnesium ions is influenced by pH and can be triggered by lowering it from neutral to 3.


Asunto(s)
Magnesio , Titanio , Preparaciones de Acción Retardada , Iones , Propiedades de Superficie
15.
Dent Mater J ; 39(3): 422-428, 2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-31969544

RESUMEN

The aim of this study was to construct a Ti-Nb-Cu ternary phase diagram that plays the role of a map for developing new titanium alloys with excellent machinability and mechanical properties. Fifteen experimental Ti-Nb-Cu ternary alloys composed of Ti-5-30%Nb-2-20%Cu were designed, and ingots made using Ar-arc melting furnace before casting to generate specimen. The alloy castings were evaluated in terms of their microstructures and alloy phases. A Ti-Nb-Ti2Cu pseudo-ternary phase diagram was constructed using X-ray diffractmetry results. Three alloy phases (α-Ti, ß-Ti and Ti2Cu) were established within the specimen. Furthermore, the prescence of two-phase coexistence regions (α+Ti2Cu, α+ß and ß+Ti2Cu), and three-phase coexistence region (α+ß+Ti2Cu) was noted. The findings obtained through microstructural observation corresponded well with the constructed phase diagram.


Asunto(s)
Aleaciones , Titanio , Aleaciones Dentales , Difracción de Rayos X
16.
Sci Signal ; 12(587)2019 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-31239324

RESUMEN

Kynurenine, which is generated from tryptophan by indoleamine 2,3-dioxygenase 1 (IDO1), binds to the aryl hydrocarbon receptor (AhR). Here, we report that kynurenine was produced by undifferentiated human embryonic stem cells (hESCs) and by induced pluripotent stem cells (iPSCs). In undifferentiated hESCs, kynurenine stimulated the AhR to promote the expression of self-renewal genes. The kynurenine-AhR complex also stimulated the expression of IDO1 and AHR, activating a positive feedback loop. Inhibition of IDO1 activity reduced the proliferation of undifferentiated ESCs but did not stimulate their differentiation. Substantial amounts of free kynurenine were present in the culture medium, providing a paracrine signal for maintenance of the undifferentiated state. Kynurenine was not present in the medium of differentiated ESCs or iPSCs. When ESCs were induced to undergo ectodermal differentiation, the abundance of kynurenine in the medium was reduced through activation of the main kynurenine catabolic pathway mediated by kynurenine aminotransferase 2 (KAT2, also known as AADAT), resulting in the secretion of 2-aminoadipic acid (2-AAA) into the culture medium. Inhibition of KAT2 activity blocked ectodermal differentiation. Thus, kynurenine metabolism plays an important role in the maintenance of the undifferentiated state and in ectodermal differentiation. Furthermore, kynurenine in the culture medium is a biomarker for the undifferentiated state, whereas the presence of 2-AAA in the culture medium is a biomarker of ESCs and iPSCs that have committed to differentiate along the ectoderm lineage.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/biosíntesis , Regulación de la Expresión Génica , Células Madre Embrionarias Humanas/metabolismo , Quinurenina/metabolismo , Receptores de Hidrocarburo de Aril/biosíntesis , Transducción de Señal , Diferenciación Celular , Línea Celular , Células Madre Embrionarias Humanas/citología , Humanos , Células Madre Pluripotentes Inducidas/metabolismo
17.
Biochem Biophys Res Commun ; 496(2): 429-435, 2018 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-29305868

RESUMEN

We are currently conducting clinical research on cell sheets for cartilage regeneration. One issue with the future use of chondrocyte sheets as cellular and tissue-based products is quality assessment. Currently, chondrocyte sheets are evaluated using invasive methods that cannot be performed on every sheet produced. We report here on our liquid chromatography-tandem mass spectrometry (LC-MS/MS) technique that allows the noninvasive assessment of every sheet using only 50 µl of culture medium. We found that LC-MS/MS could be used to confirm cell sheet viability through the measurement of glucose and glutamine uptake, to estimate extracellular matrix production by measuring serine consumption, to estimate cell kinetics by measuring cytidine and uracil concentrations, and to estimate melanoma inhibitory activity level by measuring pyridoxal concentration. LC-MS/MS may be useful for the noninvasive assessment of products to be used in regenerative medicine.


Asunto(s)
Cartílago/metabolismo , Condrocitos/metabolismo , Cromatografía Liquida/normas , Regeneración/fisiología , Espectrometría de Masas en Tándem/normas , Transporte Biológico , Cartílago/patología , Cartílago/cirugía , Citidina/metabolismo , Matriz Extracelular , Glucosa/metabolismo , Glutamina/metabolismo , Humanos , Control de Calidad , Medicina Regenerativa/métodos , Serina/metabolismo , Uracilo/metabolismo
18.
ACS Omega ; 3(12): 18323-18333, 2018 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-31458409

RESUMEN

We developed a high-power abiotic direct glucose fuel cell system using a Au-Pt bimetallic anode catalyst. The high power generation (95.7 mW cm-2) was attained by optimizing operating conditions such as the composition of a bimetallic anode catalyst, loading amount of the metal catalyst on a carbon support, ionomer/carbon weight ratio when the catalyst was applied to the anode, glucose and KOH concentrations in the fuel solution, and operating temperature and flow rate of the fuel solution. It was found that poly(N-vinyl-2-pyrrolidone)-stabilized Au80Pt20 nanoparticles (mean diameter 1.5 nm) on a carbon (Ketjen Black 600) support function as a highly active anode catalyst for the glucose electrooxidation. The ionomer/carbon weight ratio also greatly affects the cell properties, which was found to be optimal at 0.2. As for the glucose concentration, a maximum cell power was derived at 0.4-0.6 mol dm-3. A high KOH concentration (4.0 mol dm-3) was preferable for deriving the maximum power. The cell power increased with the increasing flow rate of the glucose solution up to 50 cm3 min-1 and leveled off thereafter. At the optimal condition, the maximum power density and corresponding cell voltage of 58.2 mW cm-2 (0.36 V) and 95.7 mW cm-2 (0.34 V) were recorded at 298 and 328 K, respectively.

19.
Intern Med ; 56(18): 2415-2421, 2017 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-28824069

RESUMEN

Objective To examine whether or not an edrophonium challenge test is useful for diagnosing cervical dystonia. Patients We evaluated 10 patients with cervical dystonia and 10 with hemifacial spasms (disease controls). We administered edrophonium and saline in this double-blinded study. Before and after the injection, we recorded the participants' clinical signs using a video camera to assess the objective symptoms every two minutes. Ten minutes after the saline and edrophonium injections, participants evaluated their subjective clinical signs using a visual analog scale. The objective signs on the video recordings were scored by specialists who were blinded to the treatment. The mean visual analog scale scores were compared using the Wilcoxon rank-sum test for paired continuous variables. Results The clinical signs of participants with cervical dystonia were amplified by edrophonium. In contrast, the clinical signs in participants with hemifacial spasms were not affected by the edrophonium challenge test. Conclusion The edrophonium challenge test may be useful for diagnosing cervical dystonia.


Asunto(s)
Edrofonio/farmacología , Tortícolis/diagnóstico , Adulto , Anciano , Método Doble Ciego , Femenino , Espasmo Hemifacial/diagnóstico , Humanos , Masculino , Persona de Mediana Edad
20.
J Chromatogr A ; 1469: 35-47, 2016 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-27712885

RESUMEN

Multivariate curve resolution-alternating least squares (MCR-ALS) method was investigated for its potential to accelerate pharmaceutical research and development. The fast and efficient separation of complex mixtures consisting of multiple components, including impurities as well as major drug substances, remains a challenging application for liquid chromatography in the field of pharmaceutical analysis. In this paper we suggest an integrated analysis algorithm functioning on a matrix of data generated from HPLC coupled with photo-diode array detector (HPLC-PDA) and consisting of the mathematical program for the developed multivariate curve resolution method using an expectation maximization (EM) algorithm with a bidirectional exponentially modified Gaussian (BEMG) model function as a constraint for chromatograms and numerous PDA spectra aligned with time axis. The algorithm provided less than ±1.0% error between true and separated peak area values at resolution (Rs) of 0.6 using simulation data for a three-component mixture with an elution order of a/b/c with similarity (a/b)=0.8410, (b/c)=0.9123 and (a/c)=0.9809 of spectra at peak apex. This software concept provides fast and robust separation analysis even when method development efforts fail to achieve complete separation of the target peaks. Additionally, this approach is potentially applicable to peak deconvolution, allowing quantitative analysis of co-eluted compounds having exactly the same molecular weight. This is complementary to the use of LC-MS to perform quantitative analysis on co-eluted compounds using selected ions to differentiate the proportion of response attributable to each compound.


Asunto(s)
Preparaciones Farmacéuticas/análisis , Acetofenonas/análisis , Benzofenonas/análisis , Butanos/análisis , Cromatografía Líquida de Alta Presión/instrumentación , Cromatografía Líquida de Alta Presión/métodos , Citidina/análisis , Fluorobencenos/análisis , Isomerismo , Cetonas/análisis , Análisis de los Mínimos Cuadrados , Espectrometría de Masas , Peso Molecular , Análisis Multivariante , Nucleótidos de Purina/análisis , Uracilo/análisis
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