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1.
Materials (Basel) ; 17(3)2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38591410

RESUMEN

Natural monoclinic zirconia (baddeleyite) was irradiated with 340 MeV Au ions, and the irradiation-induced nanostructures (i.e., ion tracks and nanohillocks) were observed using transmission electron microscopy. The diameter of the nanohillocks was approximately 10 nm, which was similar to the maximum molten region size calculated using the analytical thermal spike model. Ion tracks were imaged as strained regions that maintained their crystalline structure. The cross-sections of most of the ion tracks were imaged as rectangular contrasts as large as 10 nm. These results strongly indicated that the molten region was recrystallized anisotropically, reflecting the lattice structure. Furthermore, low-density track cores were formed in the center of the ion tracks. The formation of low-density track cores can be attributed to the ejection of molten matter toward the surface. A comparison of the ion tracks in the synthetic zirconia nanoparticles and those in larger natural zirconia samples showed that the interface between the strained track contrast and the matrix was less clear in the former than in the latter. These findings suggest that the recrystallization process was affected by the size of the irradiated samples.

2.
Sci Rep ; 13(1): 22781, 2023 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-38123631

RESUMEN

Organoids, which can reproduce the complex tissue structures found in embryos, are revolutionizing basic research and regenerative medicine. In order to use organoids for research and medicine, it is necessary to assess the composition and arrangement of cell types within the organoid, i.e., spatial gene expression. However, current methods are invasive and require gene editing and immunostaining. In this study, we developed a non-invasive estimation method of spatial gene expression patterns using machine learning. A deep learning model with an encoder-decoder architecture was trained on paired datasets of phase-contrast and fluorescence images, and was applied to a retinal organoid derived from mouse embryonic stem cells, focusing on the master gene Rax (also called Rx), crucial for eye field development. This method successfully estimated spatially plausible fluorescent patterns with appropriate intensities, enabling the non-invasive, quantitative estimation of spatial gene expression patterns within each tissue. Thus, this method could lead to new avenues for evaluating spatial gene expression patterns across a wide range of biology and medicine fields.


Asunto(s)
Células Madre Pluripotentes , Retina , Ratones , Animales , Retina/metabolismo , Organoides/metabolismo , Medicina Regenerativa , Expresión Génica
3.
J Phys Condens Matter ; 35(41)2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37419121

RESUMEN

It is well-known that eutectic gold-silicon (Au-Si) alloys exhibit anomalous melting point depression, which is more than 1000 °C from the melting point of elemental Si (1414 °C). The melting point depression in eutectic alloys is generally explained in terms of a decrease of the free energy by mixing. However, it is difficult to understand the anomalous melting point depression only from the stability of the homogeneous mixing. Some researchers suggest that there are concentration fluctuations in the liquids, where the atoms are inhomogeneously mixed. In this paper, we measure the small-angle neutron scattering (SANS) of Au81.4Si18.6(eutectic composition) and Au75Si25(off-eutectic composition) at temperatures from room temperature to 900 °C in both solid and liquid states to observe such concentration fluctuations directly. It is surprising that large SANS signals are observed in the liquids. This indicates that there are concentration fluctuations in the liquids. The concentration fluctuations are characterized by either the correlation lengths in multiple length scales or surface fractals. This finding yields new insight into the mixing state in the eutectic liquids. The mechanism of the anomalous melting point depression is discussed based on the concentration fluctuations.

4.
J Opt Soc Am A Opt Image Sci Vis ; 40(1): 116-128, 2023 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-36607080

RESUMEN

Layered surface objects represented by decorated tomb murals and watercolors are in danger of deterioration and damage. To address these dangers, it is necessary to analyze the pigments' thickness and mixing ratio and record the current status. This paper proposes an unsupervised autoencoder model for thickness and mixing ratio estimation. The input of our autoencoder is spectral data of layered surface objects. Our autoencoder is unique, to our knowledge, in that the decoder part uses a physical model, the Kubelka-Munk model. Since we use the Kubelka-Munk model for the decoder, latent variables in the middle layer can be interpretable as the pigment thickness and mixing ratio. We conducted a quantitative evaluation using synthetic data and confirmed that our autoencoder provides a highly accurate estimation. We measured an object with layered surface pigments for qualitative evaluation and confirmed that our method is valid in an actual environment. We also present the superiority of our unsupervised autoencoder over supervised learning.

5.
ACS Sens ; 6(9): 3409-3415, 2021 09 24.
Artículo en Inglés | MEDLINE | ID: mdl-34264071

RESUMEN

A self-driven sensor that can detect urine and urine sugar and can be mounted on diapers is desirable to reduce the burden of long-term care. In this study, we created a paper-based glucose biofuel cell that can be mounted on diapers to detect urine sugar. Electrodes for biofuel cells were produced by printing MgO-templated porous carbon on which poly(glycidyl methacrylate) was modified using graft polymerization. A new bioanode was prepared through covalently modifying flavin-adenine-dinucleotide-dependent glucose dehydrogenase and azure A with pendant glycidyl groups of poly(glycidyl methacrylate). We prepared a cathode with covalently bonded bilirubin oxidase. Covalent bonding of enzymes and mediators to both the bioanode and biocathode suppressed elution and improved stability. The biofuel cell could achieve a maximum output density of 0.12 mW cm-2, and by combining it with a wireless transmission device, the concentration of glucose sensed from the transmission frequency was in the range of 0-10 mM. The sensitivity of the sensor was estimated at 0.0030 ± 0.0002 Hz mmol-1 dm3. This device is expected to be a new urine-sugar detection device, composed only of organic materials with a low environmental load and it can be useful for detecting postprandial hyperglycemia.


Asunto(s)
Fuentes de Energía Bioeléctrica , Glucosa
6.
IEEE Trans Pattern Anal Mach Intell ; 42(3): 708-719, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30582528

RESUMEN

Images captured in participating media such as murky water, fog, or smoke are degraded by scattered light. Thus, the use of traditional three-dimensional (3D) reconstruction techniques in such environments is difficult. In this paper, we propose a photometric stereo method for participating media. The proposed method differs from prvious studies with respect to modeling shape-dependent forward scatter. In the proposed model, forward scatter is described as an analytical form using lookup tables and is represented by spatially-variant kernels. We also propose an approximation of a large-scale dense matrix as a sparse matrix, which enables the removal of forward scatter. We discuss the approximation in the proposed method using synthesized data. Then, experiments with real data demonstrate that the proposed method improves 3D reconstruction in participating media.

7.
Endocr J ; 65(8): 859-867, 2018 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-29806620

RESUMEN

Sodium-glucose co-transporter-2 inhibitors are newly established anti-diabetic agents with a unique glucose-lowering mechanism. In the present study, we investigated the efficacy and safety of the sodium-glucose co-transporter-2 inhibitor ipragliflozin (Ipra) for metabolic markers and cardiovascular parameters in Japanese patients with type 2 diabetes mellitus (T2DM). This study was an investigator-initiated, open-label, single-arm, multicenter prospective study. Patients with T2DM were treated with 50 mg Ipra for 24 and 52 weeks. The primary outcome investigated was the reduction of glycated hemoglobin (HbA1c) level. The secondary outcome was the change in other metabolic and cardiovascular parameters by 24 weeks. Before and after 52 weeks of treatment, carotid intima-media thickening (IMT) was measured by echography. A total of 134 patients were recruited in the study. A 24-week treatment with 50 mg Ipra daily significantly reduced HbA1c level (-0.6%, p < 0.01). Body mass index (BMI), blood pressure and serum C-peptide were reduced significantly (p < 0.05), while serum glucagon level was unchanged. Interestingly, the serum adiponectin and high-density lipoprotein (HDL) cholesterol levels were significantly increased by Ipra. However, 52 weeks of Ipra treatment did not change carotid IMT. Multiple regression analysis revealed that the only significant contributing factor for HbA1c reduction by Ipra was baseline HbA1c level. These data suggest that Ipra decreased not only glucose level but also BMI, blood pressure and serum C-peptide, and the contributing factor for HbA1c reduction by Ipra was baseline HbA1c level. Further, Ipra improved serum adiponectin and HDL cholesterol levels.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Glucósidos/uso terapéutico , Hipoglucemiantes/uso terapéutico , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Tiofenos/uso terapéutico , Adiponectina/sangre , Adulto , Anciano , Glucemia , Índice de Masa Corporal , Péptido C/sangre , Diabetes Mellitus Tipo 2/sangre , Femenino , Glucósidos/efectos adversos , Humanos , Hipoglucemiantes/efectos adversos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Inhibidores del Cotransportador de Sodio-Glucosa 2/efectos adversos , Tiofenos/efectos adversos , Resultado del Tratamiento , Adulto Joven
8.
Intern Med ; 57(17): 2467-2472, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-29709936

RESUMEN

Objectives We retrospectively investigated the clinical and endocrinological characteristics of adrenal incidentalomas. Methods We studied 61 patients who had been diagnosed with adrenal incidentalomas and had undergone detailed clinical and endocrinological evaluations while hospitalized. We used common criteria to diagnose the functional tumors, but for sub-clinical Cushing's syndrome, we used an updated set of diagnosis criteria: serum cortisol ≥1.8 µg/dL after a positive response to a 1-mg dexamethasone suppression test if the patient has a low morning adrenocorticotropic hormone (ACTH) level (<10 pg/mL) and a loss of the diurnal serum cortisol rhythm. Results Of the 61 patients, none (0%) had malignant tumors, 8 (13.1%) had pheochromocytoma, and 15 (24.6%) had primary aldosteronism; when diagnosed by our revised criteria, 13 (21.3%) had cortisol-secreting adenomas (Cushing's syndrome and sub-clinical Cushing's syndrome), and 25 (41.0%) had non-functional tumors. Compared with the non-functional tumor group, the primary aldosteronism group and the cortisol-secreting adenoma group were significantly younger and had significantly higher rates of hypokalemia, whereas the pheochromocytoma group had significantly larger tumors and a significantly lower body mass index. Conclusion Our study found a larger percentage of functional tumors among adrenal incidentalomas than past reports, partly because we used a lower serum cortisol level after a dexamethasone suppression test to diagnose sub-clinical Cushing's syndrome and because all of the patients were hospitalized and could therefore receive more detailed examinations. Young patients with hypokalemia or lean patients with large adrenal tumors warrant particularly careful investigation.


Asunto(s)
Adenoma/diagnóstico , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Síndrome de Cushing/diagnóstico , Hiperaldosteronismo/diagnóstico , Feocromocitoma/diagnóstico , Adenoma/complicaciones , Neoplasias de las Glándulas Suprarrenales/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Ritmo Circadiano , Síndrome de Cushing/complicaciones , Dexametasona , Femenino , Humanos , Hidrocortisona/sangre , Hiperaldosteronismo/complicaciones , Japón , Masculino , Persona de Mediana Edad , Feocromocitoma/complicaciones , Estudios Retrospectivos
9.
PLoS One ; 12(8): e0182699, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28797123

RESUMEN

BACKGROUND AND PURPOSE: Xanthine oxidoreductase (XOR), which catalyzes purine catabolism, has two interconvertible forms, xanthine dehydrogenase and xanthine oxidase, the latter of which produces superoxide during uric acid (UA) synthesis. An association between plasma XOR activity and cardiovascular and renal outcomes has been previously suggested. We investigated the potential association between cardiac parameters and plasma XOR activity among cardiology patients. METHODS AND RESULTS: Plasma XOR activity was measured by [13C2,15N2]xanthine coupled with liquid chromatography/triplequadrupole mass spectrometry. Among 270 patients who were not taking UA-lowering drugs, XOR activity was associated with body mass index (BMI), alanine aminotransferase (ALT), HbA1c and renal function. Although XOR activity was not associated with serum UA overall, patients with chronic kidney disease (CKD), those with higher XOR activity had higher serum UA among patients without CKD. Compared with patients with the lowest XOR activity quartile, those with higher three XOR activity quartiles more frequently had left ventricular hypertrophy. In addition, plasma XOR activity showed a U-shaped association with low left ventricular ejection fraction (LVEF) and increased plasma B-type natriuretic peptide (BNP) levels, and these associations were independent of age, gender, BMI, ALT, HbA1C, serum UA, and CKD stages. CONCLUSIONS: Among cardiac patients, left ventricular hypertrophy, low LVEF, and increased BNP were significantly associated with plasma XOR activity independent of various confounding factors. Whether pharmaceutical modification of plasma XOR activity might inhibit cardiac remodeling and improve cardiovascular outcome should be investigated in future studies.


Asunto(s)
Hipertrofia Ventricular Izquierda/sangre , Volumen Sistólico , Xantina Deshidrogenasa/sangre , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Femenino , Humanos , Hipertrofia Ventricular Izquierda/enzimología , Hipertrofia Ventricular Izquierda/fisiopatología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Función Ventricular Izquierda
10.
Opt Lett ; 41(13): 2994-7, 2016 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-27367084

RESUMEN

We report a dual-frequency injection-locked continuous-wave near-infrared laser. The entire system consists of a Ti:sapphire ring laser as a power oscillator, two independent diode lasers employed as seed lasers, and a master cavity providing a frequency reference. Stable dual-frequency injection-locked oscillation is achieved with a maximum output power of 2.8 W. We show its single longitudinal/transverse mode characteristics and practical power stability, as fundamental performance features of this laser system. We also demonstrate arbitrary selectivity of the two frequencies and flexible control of their relative powers by simply manipulating the seed lasers, as advanced features.

11.
Chem Commun (Camb) ; 49(36): 3793-5, 2013 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-23545892

RESUMEN

A palladium catalyst hybridised with a titanium dioxide photocatalyst can promote cyanomethylation of an aromatic ring by using acetonitrile, where the photocatalyst activates acetonitrile to form a cyanomethyl radical before the C-C bond formation using the palladium catalyst.

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