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1.
Nano Lett ; 23(7): 2490-2495, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36944354

RESUMEN

Optically induced GHz-THz guided acoustic waves have been intensively studied because of the potential to realize noninvasive and noncontact material inspection. Although the generation of photoinduced guided acoustic waves utilizing nanostructures, such as ultrathin plates, nanowires, and materials interfaces, is being established, experimental characterization of these acoustic waves in consideration of the finite size effect has been difficult due to the lack of experimental methods with nm × ps resolution. Here we experimentally observe the sub-micrometer guided acoustic waves in a nanofabricated ultrathin silicon plate by ultrafast transmission electron microscopy with nm × ps precision. We successfully characterize the excited guided acoustic wave in frequency-wavenumber space by applying Fourier-transformation analysis on the bright-field movie. These results suggest the great potential of ultrafast transmission electron microscopy to characterize the acoustic modes realized in various nanostructures.

2.
Gan To Kagaku Ryoho ; 48(10): 1251-1254, 2021 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-34657057

RESUMEN

Palbociclib, a CDK4/6 inhibitor, is found to be an effective therapeutic drug in the treatment of estrogen receptor positive (ER+)metastatic breast cancer. In this report, we describe a case of rapid progression of life-threatening multiple bone metastases of breast cancer treated with a combination of fulvestrant and palbociclib. The patient, a 58-year-old postmenopausal woman, was diagnosed with left breast cancer at the age of 43 years and underwent breast-conserving surgery. After the completion of postoperative adjuvant endocrine therapy and radiotherapy, the patient was placed on regular follow-up. Eleven years after the surgery, multiple bone metastases and multiple lymph node metastases occurred, and the patient was treated with letrozole as first-line therapy for recurrent breast cancer. Although she continued to receive this treatment for 2 years and 10 months, her general condition worsened due to the occurrence of new liver metastases and the rapid progression of existing metastatic lesions. Thus, she was sent to an emergency room. Marked hypercalcemia and a severe decrease in erythrocyte and platelet counts were observed, which could be the cause of her worsening general condition. Her performance status(PS)was 4, and palliative treatment was also considered. However, she received treatment for hypercalcemia and red blood cell transfusion; as a result, she recovered to the PS 2 where she could begin chemotherapy. Then, she began a treatment consisting of a combination of fulvestrant and palbociclib as a second-line treatment for the recurrence. The patient responded well to the treatment, and her general condition improved to PS 1. She has since maintained a good quality of life for 2 years and 11 months without serious adverse events. In conclusion, the combination of fulvestrant and palbociclib has a low risk of serious adverse events and is a worthwhile treatment for rapidly progressing, life-threatening multiple bone metastases of breast cancer.


Asunto(s)
Neoplasias de la Mama , Receptores de Estrógenos , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Fulvestrant/uso terapéutico , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Piperazinas , Piridinas , Calidad de Vida , Receptor ErbB-2
3.
Biochem Biophys Res Commun ; 578: 115-121, 2021 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-34562651

RESUMEN

Earth's gravity is essential for maintaining skeletal muscle mass and function in the body. The role of gravity in the myogenic mechanism has been studied with animal experiments in the International Space Station. Recently, gravity-control devices allow to study the effects of gravity on cultured cells on the ground. This study demonstrated that simulated microgravity accelerated aging of human skeletal muscle myoblasts in an in-vitro culture. The microgravity culture induced a significant decrease in cell proliferation and an enlargement of the cytoskeleton and nucleus of cells. Similar changes are often observed in aged myoblasts following several passages. In fact, by the microgravity culture the expression of senescence associated ß-Gal was significantly enhanced, and some muscle-specific proteins decreased in the enlarged cells. Importantly, these microgravity effects remained with the cells even after a return to normal gravity conditions. Consequently, the microgravity-affected myoblasts demonstrated a reduced capability of differentiation into myotubes. In the body, it is difficult to interpret the disability of microgravity-affected myoblasts, since muscle regeneration is linked to the supply of new myogenic cells. Therefore, our in-vitro cell culture study will be advantageous to better understand the role of each type of myogenic cell in human muscle without gravitational stress at the single cell level.


Asunto(s)
Fibras Musculares Esqueléticas/patología , Músculo Esquelético/patología , Mioblastos Esqueléticos/patología , Análisis de la Célula Individual/métodos , Simulación de Ingravidez/métodos , Envejecimiento/fisiología , Técnicas de Cultivo de Célula , Diferenciación Celular/fisiología , Citoesqueleto/metabolismo , Humanos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Mioblastos Esqueléticos/metabolismo
4.
Gan To Kagaku Ryoho ; 48(8): 1065-1068, 2021 Aug.
Artículo en Japonés | MEDLINE | ID: mdl-34404078

RESUMEN

A 57-year-old Japanese woman underwent partial mastectomy of the right breast and sentinel lymph node biopsy in July 2005. The diagnosis was mucinous carcinoma with negative margins and no lymph node metastases(pT1cN0M0, pStage Ⅰ A). Postoperative adjuvant therapy included radiation therapy and oral administration of anastrozole for 5 years. In December 2015, we observed enlargement of left supraclavicular lymph nodes; a needle biopsy revealed lymph node metastases from breast cancer. We administered toremifene and the swelling disappeared. The patient was subsequently referred to the hospital for urinary frequency in November 2016. Imaging demonstrated a bladder tumor. Transurethral biopsy of bladder revealed adenocarcinoma with mucin production consistent with breast primary. After systemic chemotherapy(UFT, eribulin), endocrine therapy(fulvestrant), and molecular targeted therapy(palbociclib), her urologic symptoms were relieved. However, 2 years and 8 months after diagnosis of bladder metastasis, the patient showed disease progression and decided to discontinue all chemotherapy and pursue palliative care. We also present a review and discussion of the relevant literature.


Asunto(s)
Adenocarcinoma Mucinoso , Neoplasias de la Mama , Carcinoma Ductal de Mama , Adenocarcinoma Mucinoso/tratamiento farmacológico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/cirugía , Femenino , Humanos , Mastectomía , Persona de Mediana Edad , Vejiga Urinaria
5.
Sci Adv ; 7(25)2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34134977

RESUMEN

Magnetic skyrmions are self-organized topological spin textures that behave like particles. Because of their fast creation and typically long lifetime, experimental verification of skyrmion's creation/annihilation processes has been challenging. Here, we successfully track skyrmion dynamics in defect-introduced Co9Zn9Mn2 by using pump-probe Lorentz transmission electron microscope. Following the nanosecond photothermal excitation, we resolve 160-nm skyrmion's proliferation at <1 ns, contraction at 5 ns, drift from 10 ns to 4 µs, and coalescence at ~5 µs. These motions relay the multiscale arrangement and relaxation of skyrmion clusters in a repeatable cycle of 20 kHz. Such repeatable dynamics of skyrmions, arising from the weakened but still persistent topological protection around defects, enables us to visualize the whole life of the skyrmions and demonstrates the possible high-frequency manipulations of topological charges brought by skyrmions.

6.
Nutrients ; 12(9)2020 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-32927677

RESUMEN

Vascular dysfunction and injurious stimuli such as oxidative stress are closely related to the risk of cardiovascular diseases (CVD). Dietary polyphenols are reported to exert beneficial effects in reducing the risk of CVD. Black soybean has been used as a nutritionally rich food and contains abundant polyphenols in its seed coat and grain. Black soybean has many beneficial physiological activities, and its prevention effects on CVD risk were reported mainly in animal experiments. In this study, we performed a randomized, single blind, placebo controlled, crossover trial to investigate the effect of black soybean consumption on the vascular function in healthy humans. Twenty-two healthy adults aged from 30 to 60 completed the four week trial with daily consumption of about a 40 g test material cookie containing 20 g roasted black soybean powder. Body composition, vascular function, biomarkers for oxidative stress, and polyphenol contents in the urine and the plasma were measured. After ingestion of the black soybean cookie, vascular function, which was evaluated by plethysmogram using a Pulse Analyzer®, was improved and systolic blood pressure was decreased. Moreover, nitric oxide levels in plasma and urine were increased, while an oxidative stress biomarker, 8-hydroxy-2'-deoxyguanosine level, in the plasma was decreased accompanied by an increase in the concentration of polyphenols derived from black soybean in plasma and urine. These results suggest that the antioxidant activity of black soybean polyphenols and an increase in the nitric oxide level may contribute to the improvement of vascular function. Thus, black soybean is an attractive food material for improvement of vascular function through decreasing oxidative stress by its potent antioxidant activity and increasing the nitric oxide level in healthy humans.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Fenómenos Fisiológicos Cardiovasculares/efectos de los fármacos , Glycine max , Polifenoles/farmacología , Adulto , Biomarcadores/sangre , Biomarcadores/orina , Enfermedades Cardiovasculares/prevención & control , Estudios Cruzados , Femenino , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Óxido Nítrico/sangre , Óxido Nítrico/orina , Estrés Oxidativo/efectos de los fármacos , Pletismografía , Polifenoles/sangre , Polifenoles/orina , Método Simple Ciego
7.
Nano Lett ; 20(7): 4932-4938, 2020 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-32463678

RESUMEN

The control of acoustic phonons, which are the carriers of sound and heat, has become the focus of increasing attention because of a demand for manipulating the sonic and thermal properties of nanometric devices. In particular, the photoacoustic effect using ultrafast optical pulses has a promising potential for the optical manipulation of phonons in the picosecond time regime. So far, its mechanism has been mostly based on the commonplace thermoelastic expansion in isotropic media, which has limited applicability. In this study, we investigate a conceptually new mechanism of the photoacoustic effect involving a structural instability that utilizes a transition-metal dichalcogenide VTe2 with a ribbon-type charge-density-wave (CDW). Ultrafast electron microscope imaging and diffraction measurements reveal the generation and propagation of unusual acoustic waves in a nanometric thin plate associated with optically induced instantaneous CDW dissolution. Our results highlight the capability of photoinduced structural instabilities as a source of coherent acoustic waves.

8.
Arch Biochem Biophys ; 688: 108408, 2020 07 30.
Artículo en Inglés | MEDLINE | ID: mdl-32470460

RESUMEN

Vascular dysfunction and injurious stimuli such as oxidative stress is closely related to the risk of cardiovascular diseases (CVD). Dietary polyphenols is reported to exert the beneficial effects on reducing the risk of CVD. Black soybean is rich in polyphenols, including isoflavones, anthocyanidins and flavan-3-ols, and its prevention effects on CVD risk were reported in the animal experiments. In this study, we investigated the effect of black soybean consumption on the vascular function and oxidative stress associating with the polyphenol concentrations in healthy women. Lowered vascular age was observed in 33 out of 44 volunteers who completed the 8-week trial. It was observed that improvement of the vascular stiffness, increasing in the urinary NO2 and NO3 level, and decreasing in the oxidative stress markers, 8-hydroxy-2'-deoxyguanosine, hexanoyl-lysine and myeloperoxidase. In addition, concentration of 12 polyphenols in black soybean increased in the plasma and urine. Increased concentration of polyphenols would be involved in the decreased oxidative stress. Thus, black soybean consumption improved the vascular function through an increase in nitric oxide and a decrease in oxidative stress accompanied by increasing the polyphenol concentrations in healthy women.


Asunto(s)
Antioxidantes/farmacología , Vasos Sanguíneos/efectos de los fármacos , Glycine max/química , Óxido Nítrico/metabolismo , Estrés Oxidativo/efectos de los fármacos , Polifenoles/farmacología , Administración Oral , Adulto , Anciano , Animales , Antioxidantes/administración & dosificación , Antioxidantes/análisis , Biomarcadores/sangre , Biomarcadores/metabolismo , Biomarcadores/orina , Presión Sanguínea , Femenino , Humanos , Persona de Mediana Edad , Óxido Nítrico/sangre , Óxido Nítrico/orina , Fotopletismografía , Polifenoles/administración & dosificación , Polifenoles/sangre , Polifenoles/orina , Adulto Joven
9.
Sci Rep ; 9(1): 2690, 2019 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-30804434

RESUMEN

Quercetin and its metabolite isorhamnetin elicit various beneficial effects on human health. However, their bioavailability is low. In this study, we investigated whether low concentrations in the physiological range could promote glucose uptake in L6 myotubes, as well as the underlying molecular mechanisms. We found that 0.1 nM and 1 nM quercetin or 1 nM isorhamnetin significantly increased glucose uptake via translocation of glucose transporter type 4 (GLUT4) to the plasma membrane of L6 myotubes. Quercetin principally activated the CaMKKß/AMPK signalling pathway at these concentrations, but also activated IRS1/PI3K/Akt signalling at 10 nM. In contrast, 1 nM and 10 nM isorhamnetin principally activated the JAK/STAT pathway. Treatment with siAMPKα and siJAK2 abolished quercetin- and isorhamnetin-induced GLUT4 translocation, respectively. However, treatment with siJAK3 did not affect isorhamnetin-induced GLUT4 translocation, indicating that isorhamnetin induced GLUT4 translocation mainly through JAK2, but not JAK3, signalling. Thus, quercetin preferably activated the AMPK pathway and, accordingly, stimulated IRS1/PI3K/Akt signalling, while isorhamnetin activated the JAK2/STAT pathway. Furthermore, after oral administration of quercetin glycoside at 10 and 100 mg/kg body weight significantly induced GLUT4 translocation to the plasma membrane of skeletal muscles in mice. In the same animals, plasma concentrations of quercetin aglycone form were 4.95 and 6.80 nM, respectively. In conclusion, at low-concentration ranges, quercetin and isorhamnetin promote glucose uptake by increasing GLUT4 translocation via different signalling pathways in skeletal muscle cells; thus, these compounds may possess beneficial functions for maintaining glucose homeostasis by preventing hyperglycaemia at physiological concentrations.


Asunto(s)
Glucosa/metabolismo , Quercetina/análogos & derivados , Quercetina/farmacología , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Transporte Biológico/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Células Cultivadas , Transportador de Glucosa de Tipo 4/genética , Transportador de Glucosa de Tipo 4/metabolismo , Inmunoprecipitación , Quinasas Janus/metabolismo , Masculino , Ratones , Fibras Musculares Esqueléticas/efectos de los fármacos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Quercetina/sangre , Ratas , Transducción de Señal/efectos de los fármacos
10.
Sci Adv ; 3(8): e1700466, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28875162

RESUMEN

A major problem in the field of high-transition temperature (Tc) superconductivity is the identification of the electronic instabilities near superconductivity. It is known that the iron-based superconductors exhibit antiferromagnetic order, which competes with the superconductivity. However, in the nonmagnetic state, there are many aspects of the electronic instabilities that remain unclarified, as represented by the orbital instability and several in-plane anisotropic physical properties. We report a new aspect of the electronic state of the optimally doped iron-based superconductors by using high-energy resolution angle-resolved photoemission spectroscopy. We find spectral evidence for the folded electronic structure suggestive of an antiferroic electronic instability, coexisting with the superconductivity in the nonmagnetic state of Ba1-x K x Fe2As2. We further establish a phase diagram showing that the antiferroic electronic structure persists in a large portion of the nonmagnetic phase covering the superconducting dome. These results motivate consideration of a key unknown electronic instability, which is necessary for the achievement of high-Tc superconductivity in the iron-based superconductors.

11.
Bioorg Med Chem ; 21(13): 3674-9, 2013 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-23685182

RESUMEN

Hypobromous acid (HOBr) is formed by eosinophil peroxidase and myeloperoxidase in the presence of H2O2, Cl(-), and Br(-) in the host defense system of humans, protecting against invading bacteria. However, the formed HOBr may cause damage to DNA and its components in the host. When a guanine nucleoside (3',5'-di-O-acetyl-2'-deoxyguansoine) was treated with HOBr at pH 7.4, spiroiminodihydantoin, guanidinohydantoin/iminoallantoin, dehydro-iminoallantoin, diimino-imidazole, amino-imidazolone, and diamino-oxazolone nucleosides were generated in addition to an 8-bromoguanine nucleoside. The major products were spiroiminodihydantoin under neutral conditions and guanidinohydantoin/iminoallantoin under mildly acidic conditions. All the products were formed in the reaction with HOCl in the presence of Br(-). These products were also produced by eosinophil peroxidase or myeloperoxidase in the presence of H2O2, Cl(-), and Br(-). The results suggest that the products other than 8-bromoguanine may also have importance for mutagenesis by the reaction of HOBr with guanine residues in nucleotides and DNA.


Asunto(s)
Bromatos/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Peroxidasa del Eosinófilo/metabolismo , Peroxidasa/metabolismo , Acetilación , Alantoína/análogos & derivados , Alantoína/metabolismo , Desoxiguanosina/química , Guanosina/análogos & derivados , Guanosina/metabolismo , Humanos , Peróxido de Hidrógeno/metabolismo , Compuestos de Espiro/metabolismo
12.
Diabetes Technol Ther ; 14(5): 423-9, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22316114

RESUMEN

BACKGROUND: We compared the effects of miglitol as an add-on to bolus insulin and dose-intensified bolus insulin on postprandial glycemic excursions by continuous glucose monitoring (CGM). SUBJECTS AND METHODS: The glucose levels of 21 type 2 diabetes patients admitted for glycemic control were monitored for three consecutive days by CGM after stable glycemic control was achieved with bolus or basal-bolus insulin therapy. During the 3-day period, bolus insulin administration was continued in 11 patients on Day 1; the dose of bolus insulin in these patients was increased by 2 U before each meal on day 2, and on day 3, 50 mg of miglitol was administered before each meal in addition to the initial dose of bolus insulin given on Day 1. In the remaining 10 patients, the order of administration on Day 2 and Day 3 was reversed. RESULTS: Of the glycemic fluctuations observed during the 24-h period, postprandial glycemic excursions showed a greater reduction during treatment with dose-intensified bolus insulin and during treatment with miglitol plus bolus insulin than during treatment with bolus insulin alone; however, miglitol plus bolus insulin treatment had a more potent effect than treatment with dose-intensified bolus insulin on reducing postprandial glycemic excursions immediately after meals. Changes in area under the curve (ΔAUC) occurring within 1 h and 2 h after each meal were significantly smaller during treatment with miglitol plus bolus insulin than during treatment with dose-intensified bolus insulin, whereas ΔAUC within >2 h after each meal, except dinner, was significantly greater during treatment with miglitol plus bolus insulin than during treatment with dose-intensified bolus insulin. CONCLUSION: Our findings suggest that miglitol as an add-on to bolus insulin in patients with type 2 diabetes may be one of the beneficial therapeutic options that provides a more rigorous postprandial glycemic control without increasing the risk for hypoglycemia before the next meal.


Asunto(s)
1-Desoxinojirimicina/análogos & derivados , Automonitorización de la Glucosa Sanguínea , Glucemia/efectos de los fármacos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Insulina/administración & dosificación , Periodo Posprandial , 1-Desoxinojirimicina/administración & dosificación , Adulto , Anciano , Área Bajo la Curva , Glucemia/metabolismo , Automonitorización de la Glucosa Sanguínea/métodos , Estudios Cruzados , Diabetes Mellitus Tipo 2/sangre , Relación Dosis-Respuesta a Droga , Femenino , Prueba de Tolerancia a la Glucosa , Hemoglobina Glucada/metabolismo , Humanos , Inyecciones Subcutáneas , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento , Adulto Joven
13.
Rinsho Shinkeigaku ; 47(6): 362-4, 2007 Jun.
Artículo en Japonés | MEDLINE | ID: mdl-17633112

RESUMEN

A 64-year-old man visited our clinic with a 9-day history of headache and fever. He had frequent, severe, electric shock-like pain in his left eye, forehead, and scalp. The body temperature was 37.1 degrees. Cranial nerve functions were intact. Limb weakness and stiff neck were absent. There were injection of the conjunctiva, a red rash on the trunk, and an eschar in the axilla. Abnormal laboratory findings included AST 40 IU, ALT 44 IU, CRP 16.0 mg/dl, WBC 11,090/microl, and proteinuria. CT scan was unremarkable. The cerebrospinal fluid (CSF) showed 2 polymorphs/microl, 6 lymphocytes/microl, 65 mg/dl of glucose, and 42 mg/dl of protein. A diagnosis of scrub typhus was made. Treatment with minocycline brought about prompt disappearance of the fever and dramatic clinical improvement. Increased antibody titers confirmed the diagnosis. Although almost all patients present with high fever and severe headache, only a small number of patients have CSF pleocytosis. The present case illustrates that pain in scrub typhus is, on rare occasions, indistinguishable from trigeminal neuralgia. Neurologists should have a high index of suspicion in patients with fever and headache during the epidemic season and should be familiar with the systemic symptoms and signs.


Asunto(s)
Fiebre/etiología , Cefalea/etiología , Tifus por Ácaros/complicaciones , Antibacterianos/uso terapéutico , Diagnóstico Diferencial , Humanos , Masculino , Persona de Mediana Edad , Minociclina/uso terapéutico , Tifus por Ácaros/diagnóstico , Tifus por Ácaros/tratamiento farmacológico , Resultado del Tratamiento , Neuralgia del Trigémino
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