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1.
Phys Chem Chem Phys ; 26(19): 14103-14107, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38695831

RESUMO

Metal-oxide nanocomposites (MONs) are of pivotal importance as electrode materials, yet lack a guiding principle to tune their phase texture. Here we report that the phase texture of MONs can be tuned at the nanoscale by controlling the nanophase separation of precursor alloys. In situ transmission electron microscopy (in situ TEM) has demonstrated that a MON material of platinum (Pt) and cerium oxide (CeO2) is obtained through promoted nanophase separation of a Pt5Ce precursor alloy in an atmosphere containing oxygen (O2) and carbon monoxide (CO). The Pt-CeO2 MON material comprised an alternating stack of nanometre-thick layers of Pt and CeO2 in different phase textures ranging from lamellae to mazes, depending on the O2 fraction in the atmosphere. Mathematical simulations have demonstrated that the phase texture of MONs originates from a balance in the atomic diffusions across the alloy precursor, which is controllable by the O2 fraction, temperature, and composition of the precursor alloys.

2.
Sci Technol Adv Mater ; 25(1): 2359360, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38882258

RESUMO

The hydrogen evolution reaction (HER) is an important phenomenon in water splitting. Consequently, the development of an active, earth-abundant, and inexpensive HER catalyst is highly desired. MoS2 has drawn considerable interest as an HER catalyst because it is composed of non-precious metal and exhibits high catalytic activity in the nanosheet form. In this study, size-controlled MoS2 particles were synthesized by ball milling. The as-prepared samples exhibited significantly enhanced electrochemical and catalytic properties compared to those of pristine bulk MoS2. Furthermore, the HER activity improved further upon the introduction of graphene into the as-prepared ball-milled samples. In particular, the MoS2 sample ball-milled for 12 h mixed with graphene exhibited optimal performance, showing an overpotential (160 mV at 10 mA cm-2) that was ~ 335 mV lower than that of pristine bulk MoS2. The superior catalytic activity was ascribed to the exposed edge sites, sulfur vacancies, and 1T phase of MoS2, as well as the noteworthy fortifying effect of the electronically conductive flexible material, graphene. The results provide a promising strategy for its application as an efficient and stable HER catalyst.


Li et al. reported MoS2-based electrocatalysts for the hydrogen evolution reaction. The superior catalytic activity was ascribed to exposed edge sites, sulfur vacancies, 1T phase, and the effect of graphene.

3.
J Hum Genet ; 67(4): 223-230, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34824372

RESUMO

Genetic testing for congenital or early-onset hearing loss patients has become a common diagnostic option in many countries. On the other hand, there are few late-onset hearing loss patients receiving genetic testing, as late-onset hearing loss is believed to be a complex disorder and the diagnostic rate for genetic testing in late-onset patients is lower than that for the congenital cases. To date, the etiology of late-onset hearing loss is largely unknown. In the present study, we recruited 48 unrelated Japanese patients with late-onset bilateral sensorineural hearing loss, and performed genetic analysis of 63 known deafness gene using massively parallel DNA sequencing. As a result, we identified 25 possibly causative variants in 29 patients (60.4%). The present results clearly indicated that various genes are involved in late-onset hearing loss and a significant portion of cases of late-onset hearing loss is due to genetic causes. In addition, we identified two interesting cases for whom we could expand the phenotypic description. One case with a novel MYO7A variant showed a milder phenotype with progressive hearing loss and late-onset retinitis pigmentosa. The other case presented with Stickler syndrome with a mild phenotype caused by a homozygous frameshift COL9A3 variant. In conclusion, comprehensive genetic testing for late-onset hearing loss patients is necessary to obtain accurate diagnosis and to provide more appropriate treatment for these patients.


Assuntos
Perda Auditiva Neurossensorial , Perda Auditiva , Patrimônio Genético , Perda Auditiva/genética , Perda Auditiva Neurossensorial/genética , Humanos , Linhagem , Fenótipo
4.
Eur J Nucl Med Mol Imaging ; 49(6): 1906-1917, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34997293

RESUMO

PURPOSE: A four-parameter risk model that included cardiac iodine-123 metaiodobenzylguanidine (MIBG) imaging and readily available clinical parameters was recently developed for prediction of 2-year cardiac mortality risk in patients with chronic heart failure. We sought to validate the ability of this risk model to predict post-discharge clinical outcomes in patients with acute decompensated heart failure (ADHF) and to compare its prognostic value with that of the Acute Decompensated Heart Failure National Registry (ADHERE) and Get With The Guidelines-Heart Failure (GWTG-HF) risk scores. METHODS: We studied 407 consecutive patients who were admitted for ADHF and survived to discharge, with definitive 2-year outcomes (death or survival). Cardiac MIBG imaging was performed just before discharge. The 2-year cardiac mortality risk was calculated using four parameters, namely age, left ventricular ejection fraction, New York Heart Association functional class, and cardiac MIBG heart-to-mediastinum ratio on delayed images. Patients were stratified into three groups based on the 2-year cardiac mortality risk: low- (< 4%), intermediate- (4-12%), and high-risk (> 12%) groups. The ADHERE and GWTG-HF risk scores were also calculated. RESULTS: There was a significant difference in the incidence of cardiac death among the three groups stratified using the 2-year cardiac mortality risk model (p < 0.0001). The 2-year cardiac mortality risk model had a higher C-statistic (0.732) for the prediction of cardiac mortality than the ADHERE and GWTG-HF risk scores. CONCLUSION: The 2-year MIBG-based cardiac mortality risk model is useful for predicting post-discharge clinical outcomes in patients with ADHF. TRIAL REGISTRATION NUMBER: UMIN000015246, 25 September 2014.


Assuntos
3-Iodobenzilguanidina , Insuficiência Cardíaca , Assistência ao Convalescente , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Radioisótopos do Iodo , Alta do Paciente , Prognóstico , Medição de Risco , Volume Sistólico , Função Ventricular Esquerda
5.
Chemistry ; 28(2): e202103643, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34881467

RESUMO

Nickel-catalyzed reductive cross-coupling of allylic difluorides with aryl iodides was achieved via allylic C-F bond activation. Based on this protocol, a series of γ-arylated monofluoroalkenes were synthesized in moderate to high yields with high Z-selectivities. Mechanistic studies suggest that the C-I bonds of the aryl iodides and the C-F bonds of the allylic difluorides were cleaved via oxidative addition and ß-fluorine elimination, respectively, where the oxidative addition of less reactive C-F bonds was avoided to permit their transformation.


Assuntos
Fluoretos , Níquel , Catálise , Iodetos , Oxirredução
6.
Eur Arch Otorhinolaryngol ; 279(6): 2805-2810, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34263358

RESUMO

PURPOSE: Chemoradiotherapy with docetaxel (DOC), cisplatin (CDDP), and 5-FU (TPF-CRT) for locally advanced external auditory canal cancer (EACC) has favorable oncological and functional outcomes. To establish TPF-CRT as a standard of care for advanced EACC, we conducted this study to determine the maximum tolerated (MTD) and recommended dose (RD) of DOC in TPF-CRT for locally advanced EACC. METHODS: To determine the recommended (RD) and maximum tolerated dose (MTD) of DOC in TPF-CRT for EACC, a phase I trial was conducted using the standard "3 + 3" design for maximum dose finding. DOC was administered twice every 4 weeks, CDDP at 70 mg/m2 and 5-FU at 700 mg/m2; patients were also receiving radiotherapy (66 Gy). Eight patients with T3 or T4 EACC were prospectively enrolled. RESULTS: Two patients treated with DOC, 50 mg/m2, and one out of six patients treated with DOC, 40 mg/m2, had dose-limiting toxicities. Prolonged febrile neutropenia was observed in three patients. Grade 3 non-hematological toxicities were observed in only three patients. At study completion, six patients survived, five of whom were disease free. CONCLUSION: The RD and MTD of DOC in TPF-CRT for locally advanced EACC are 40 mg/m2 when doses of CDDP and 5-FU are 70 mg/m2 and 700 mg/m2, respectively.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Escamosas/patologia , Quimiorradioterapia/efeitos adversos , Cisplatino , Docetaxel , Meato Acústico Externo/patologia , Fluoruracila , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Humanos , Taxoides
7.
Molecules ; 27(23)2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36500350

RESUMO

Hydrogen boride (HB) sheets are two-dimensional materials comprising a negatively charged hexagonal boron network and positively charged hydrogen atoms with a stoichiometric ratio of 1:1. Herein, we report the spontaneous formation of highly dispersed Ni nanoclusters on HB sheets. The spontaneous reduction reaction of Ni ions by the HB sheets was monitored by in-situ measurements with an ultraviolet-visible spectrometer. Acetonitrile solutions of Ni complexes and acetonitrile dispersions of the HB sheets were mixed in several molar ratios (the HB:Ni molar ratio was varied from 100:0.5 to 100:20), and the changes in the absorbance were measured over time. In all cases, the results suggest that Ni metal clusters grow on the HB sheets, considering the increase in absorbance with time. The absorbance peak position shifts to the higher wavelength as the Ni ion concentration increases. Transmission electron microscopy images of the post-reaction products indicate the formation of Ni nanoclusters, with sizes of a few nanometers, on the HB sheets, regardless of the preparation conditions. These highly dispersed Ni nanoclusters supported on HB sheets will be used for catalytic and plasmonic applications and as hydrogen storage materials.


Assuntos
Hidrogênio , Catálise , Microscopia Eletrônica de Transmissão , Concentração de Íons de Hidrogênio
8.
FASEB J ; 34(2): 2041-2054, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31916304

RESUMO

Most eukaryotic cells generate adenosine triphosphate (ATP) through the oxidative phosphorylation system (OXPHOS) to support cellular activities. In cultured cell-based experiments, we recently identified the hypoxia-inducible protein G0/G1 switch gene 2 (G0s2) as a positive regulator of OXPHOS, and showed that G0s2 protects cultured cardiomyocytes from hypoxia. In this study, we examined the in vivo protective role of G0s2 against hypoxia by generating both loss-of-function and gain-of-function models of g0s2 in zebrafish. Zebrafish harboring transcription activator-like effector nuclease (TALEN)-mediated knockout of g0s2 lost hypoxic tolerance. Conversely, cardiomyocyte-specific transgenic zebrafish hearts exhibited strong tolerance against hypoxia. To clarify the mechanism by which G0s2 protects cardiac function under hypoxia, we introduced a mitochondrially targeted FRET-based ATP biosensor into zebrafish heart to visualize ATP dynamics in in vivo beating hearts. In addition, we employed a mosaic overexpression model of g0s2 to compare the contraction and ATP dynamics between g0s2-expressing and non-expressing cardiomyocytes, side-by-side within the same heart. These techniques revealed that g0s2-expressing cardiomyocyte populations exhibited preserved contractility coupled with maintained intra-mitochondrial ATP concentrations even under hypoxic condition. Collectively, these results demonstrate that G0s2 provides ischemic tolerance in vivo by maintaining ATP production, and therefore represents a promising therapeutic target for hypoxia-related diseases.


Assuntos
Proteínas de Ciclo Celular , Transferência Ressonante de Energia de Fluorescência , Isquemia Miocárdica , Miocárdio , Proteínas de Peixe-Zebra , Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Isquemia Miocárdica/genética , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Fosforilação Oxidativa , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
9.
Circ J ; 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33597323

RESUMO

BACKGROUND: The effect of incidental pulmonary embolism (PE) on long-term prognosis in cancer patients is unclear. This study assessed the characteristics of cancer and venous thromboembolism (VTE) and the effect of incidental PE identified by oncologists on long-term survival of patients with cancer.Methods and Results:This single-center, retrospective, cohort study used hospital-based cancer registry data from the Osaka International Cancer Institute linked with electronic medical records and administrative data from Japan's Diagnosis Procedure Combination Per-diem Payment System. Overall, 15,689 cancer patients underwent contrast-enhanced thoracic computed tomography during 2010-2018. After excluding patients with missing data, symptomatic patients, or patients with suspected PE, 174 with incidental PE (PE+ group) and 13,197 with no PE (PE- group) were identified. The total incidence of incidental PE was 1.3%. No deaths from thrombotic events were identified in the PE+ group. Both groups were adjusted for cancer- and VTE-related characteristics using inverse probability weighting. After adjusting for immortal time bias in the PE+ group, Kaplan-Meier analysis revealed that all-cause mortality was higher in the PE+ group (hazard ratio, 2.26; 95% confidence interval, 1.53-3.33). A Cox proportional hazard model revealed that metastatic cancer and a history of curative treatment were significant prognostic factors, whereas central PE and residual proximal deep vein thrombosis were not. CONCLUSIONS: Incidental PE in cancer patients indicates poorer prognosis. Cancer-related but not thrombosis-related factors determine prognosis.

10.
BMC Cardiovasc Disord ; 21(1): 177, 2021 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-33849438

RESUMO

BACKGROUND: The incidence of concurrent cancer and ischaemic heart disease (IHD) is increasing; however, the long-term patient prognoses remain unclear. METHODS: Five-year all-cause mortality data pertaining to patients in the Osaka Cancer Registry, who were diagnosed with colorectal, lung, prostate, and gastric cancers between 2010 and 2015, were retrieved and analysed together with linked patient administrative data. Patient characteristics (cancer type, stage, and treatment; coronary risk factors; medications; and time from cancer diagnosis to index admission for percutaneous coronary intervention [PCI] or IHD diagnosis) were adjusted for propensity score matching. Three groups were identified: patients who underwent PCI within 3 years of cancer diagnosis (n = 564, PCI + group), patients diagnosed with IHD within 3 years of cancer diagnosis who did not undergo PCI (n = 3058, PCI-/IHD + group), and patients without IHD (n = 27,392, PCI-/IHD- group). Kaplan-Meier analysis was used for comparisons. RESULTS: After propensity score matching, the PCI + group had better prognosis (n = 489 in both groups, hazard ratio 0.64, 95% confidence interval 0.51-0.81, P < 0.001) than the PCI-/IHD + group. PCI + patients (n = 282) had significantly higher mortality than those without IHD (n = 280 in each group, hazard ratio 2.88, 95% confidence interval 1.90-4.38, P < 0.001). CONCLUSIONS: PCI might improve the long-term prognosis in cancer patients with IHD. However, these patients could have significantly worse long-term prognosis than cancer patients without IHD. Since the present study has some limitations, further research will be needed on this important topic in cardio-oncology.


Assuntos
Isquemia Miocárdica/terapia , Neoplasias/epidemiologia , Intervenção Coronária Percutânea , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Japão/epidemiologia , Masculino , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/mortalidade , Neoplasias/diagnóstico , Neoplasias/mortalidade , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/mortalidade , Sistema de Registros , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
11.
Proc Natl Acad Sci U S A ; 115(9): E2077-E2084, 2018 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-29440379

RESUMO

Neurofibromatosis type II (NF2) is a disease that needs new solutions. Vestibular schwannoma (VS) growth causes progressive hearing loss, and the standard treatment, including surgery and radiotherapy, can further damage the nerve. There is an urgent need to identify an adjunct therapy that, by enhancing the efficacy of radiation, can help lower the radiation dose and preserve hearing. The mechanisms underlying deafness in NF2 are still unclear. One of the major limitations in studying tumor-induced hearing loss is the lack of mouse models that allow hearing testing. Here, we developed a cerebellopontine angle (CPA) schwannoma model that faithfully recapitulates the tumor-induced hearing loss. Using this model, we discovered that cMET blockade by crizotinib (CRZ) enhanced schwannoma radiosensitivity by enhancing DNA damage, and CRZ treatment combined with low-dose radiation was as effective as high-dose radiation. CRZ treatment had no adverse effect on hearing; however, it did not affect tumor-induced hearing loss, presumably because cMET blockade did not change tumor hepatocyte growth factor (HGF) levels. This cMET gene knockdown study independently confirmed the role of the cMET pathway in mediating the effect of CRZ. Furthermore, we evaluated the translational potential of cMET blockade in human schwannomas. We found that human NF2-associated and sporadic VSs showed significantly elevated HGF expression and cMET activation compared with normal nerves, which correlated with tumor growth and cyst formation. Using organoid brain slice culture, cMET blockade inhibited the growth of patient-derived schwannomas. Our findings provide the rationale and necessary data for the clinical translation of combined cMET blockade with radiation therapy in patients with NF2.


Assuntos
Perda Auditiva/etiologia , Neurofibromatose 2/complicações , Neurofibromatose 2/radioterapia , Neuroma Acústico/complicações , Neuroma Acústico/radioterapia , Proteínas Proto-Oncogênicas c-met/metabolismo , Adolescente , Adulto , Animais , Encéfalo/metabolismo , Dano ao DNA , Feminino , Audição , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neurilemoma/complicações , Neurilemoma/radioterapia , Neurofibromina 2/genética , Técnicas de Cultura de Órgãos , Radioterapia , Transdução de Sinais , Adulto Jovem
12.
Angew Chem Int Ed Engl ; 60(9): 4747-4755, 2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33215803

RESUMO

A facile anisotropic surface modification and etching strategy is presented for the synthesis of hollow structured ZIF-67 nanoframes. The strategy uses structural and compositional distinctions between each crystallographic facet of truncated rhombic dodecahedrons ZIF-67 (tZIF-67 RDs) and the moderate coordinating and etching effects of cyanuric acid (CA). The CA can anisotropically modify and protect the {110} facets from etching, causing the six {100} facets be selectively etched via an inside-out manner, and finally forming the hollow nanoframes. The surface-modified hollow tZIF-67 RDs can be facet-selectively etched by metal salts in an outside-in manner to give metal-doped tZIF-67 nanoframes. After calcination, the metal-tZIF-67 hybrids are converted into metal-Co alloy/C composite catalysts with hollow nanoframed structures. The PtCo/C catalyst with only 5.9 wt % Pt exhibits high catalytic activities and stabilities in the hydrogen evolution reaction (HER) in acidic solutions.

13.
Beilstein J Org Chem ; 17: 396-403, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33633807

RESUMO

A facile synthesis of carbo- and heterohelicenes was achieved via tandem cycloaromatization of bisacetal precursors, which were readily prepared through C-C bond formation by Suzuki-Miyaura coupling. This cyclization was efficiently realized by a catalytic amount of trifluoromethanesulfonic acid (TfOH) in a cation-stabilizing solvent, 1,1,1,3,3,3-hexafluoropropan-2-ol (HFIP), which readily allowed gram-scale syntheses of higher-order helicenes, double helical helicenes, and heterohelicenes.

14.
Philos Trans A Math Phys Eng Sci ; 378(2186): 20190602, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33100163

RESUMO

A new environmental high-voltage transmission electron microscope (E-HVEM) was developed by Nagoya University in collaboration with JEOL Ltd. An open-type environmental cell was employed to enable in-situ observations of chemical reactions on catalyst particles as well as mechanical deformation in gaseous conditions. One of the reasons for success was the application of high-voltage transmission electron microscopy to environmental (in-situ) observations in the gas atmosphere because of high transmission of electrons through gas layers and thick samples. Knock-on damages to samples by high-energy electrons were carefully considered. In this paper, we describe the detailed design of the E-HVEM, recent developments and various applications. This article is part of a discussion meeting issue 'Dynamic in situ microscopy relating structure and function'.

15.
Clin Exp Nephrol ; 24(7): 638-645, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32236783

RESUMO

BACKGROUND: Although a shortage in organ donation is a critical problem in Japan, understanding of and attitude toward organ transplantation in medical students have not been sufficiently reported. METHODS: Between 2013 and 2018, we surveyed 702 medical students in the fifth-year clinical training in our urology department. The survey concerned (1) knowledge of Japanese transplantation law, which was amended in 2010, and (2) whether the respondents had an organ donor card and had agreed to be a brain-dead donor or a living donor in kidney transplantation with specific reasons for their choices. RESULTS: All 702 students answered the survey. Of 657 students who provided valid answers to the first section, 402 (61%) recognized the amendment to the Japanese transplantation law, and only 11 (1.7%) fully understood its contents. Of 702 students, 194 (28%) had a donor card, 384 (55%) agreed to be a brain-dead donor, and 529 (75%) agreed to be a living donor in kidney transplantation. As the specific reasons for their choices, only a few medical students wrote reasons based on their medical standpoint, and more students wrote emotional reasons. CONCLUSIONS: The understanding of and attitude toward organ transplantation were not remarkably high in the fifth-year medical students in Japan. To solve the donor shortage problem, education about organ transplantation may need to be more effective.


Assuntos
Atitude , Morte Encefálica , Transplante de Rim/legislação & jurisprudência , Doadores Vivos/provisão & distribuição , Estudantes de Medicina/estatística & dados numéricos , Adulto , Estudos Transversais , Emoções , Humanos , Japão , Estudantes de Medicina/psicologia , Obtenção de Tecidos e Órgãos , Adulto Jovem
16.
Sci Technol Adv Mater ; 21(1): 573-583, 2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32939181

RESUMO

Two highly active and stable Pd-based intermetallic nanocrystals with early d-metals Pd3Ti and Pd3Zr have been developed. The nanocrystals are synthesized by co-reduction of the respective salts of Pd and Ti/Zr. Hard X-ray photoemission Spectroscopy (HAXPES) analysis of the nanocrystals indicates that the electronic properties of Pd are modified significantly, as evident from the lowering of the d-band center of Pd. The intermetallic nanocrystals dispersed in Vulcan carbon, Pd3Ti/C and Pd3Zr/C, exhibit improved electrocatalytic activity towards methanol and ethanol oxidation in an alkaline medium (0.5 M KOH), compared to those of commercially available catalysts such as Pd/C, Pt/C, and Pt3Sn/C. In addition, Pd3Ti/C and Pd3Zr/C show significantly higher activity towards the oxidation of formic acid in an acidic medium (0.5 M H2SO4), compared to those of Pd/C and Pt/C. The modification of the d-band center of Pd as a result of the alloying of Pd with the early d-metals Ti and Zr may be responsible for the enhanced catalytic activity.

17.
Angew Chem Int Ed Engl ; 59(9): 3601-3608, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-31777142

RESUMO

High-resolution scanning electrochemical cell microscopy (SECCM) is used to image and quantitatively analyze the hydrogen evolution reaction (HER) catalytically active sites of 1H-MoS2 nanosheets, MoS2 , and WS2 heteronanosheets. Using a 20 nm radius nanopipette and hopping mode scanning, the resolution of SECCM was beyond the optical microscopy limit and visualized a small triangular MoS2 nanosheet with a side length of ca. 130 nm. The electrochemical cell provides local cyclic voltammograms with a nanoscale spatial resolution for visualizing HER active sites as electrochemical images. The HER activity difference of edge, terrace, and heterojunction of MoS2 and WS2 were revealed. The SECCM imaging directly visualized the relationship of HER activity and number of MoS2 nanosheet layers and unveiled the heterogeneous aging state of MoS2 nanosheets. SECCM can be used for improving local HER activities by producing sulfur vacancies using electrochemical reaction at the selected region.

18.
Small ; 15(22): e1805432, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31026109

RESUMO

Nanoporous metals represent a class of functional materials with unique bicontinuous open porous structural properties, making them ideal candidates for various catalyst applications. However, the pursuit of nanoporous properties, extremely small pores, and high surface area, results in the restriction of mass transport. Herein, a free-standing hierarchical nanoporous Cu material, prepared by a selective laser melting 3D printing technique and a one-step dealloying process, is presented as a highly efficient electrocatalyst for methanol oxidation. It is demonstrated that the digitally controlled hierarchical structure with macro- and nano-scaled pores can be utilized for promoting and directing mass transport as well as for the enhancement of catalytic properties. This work highlights a facile, low-cost, and alternative strategy for hierarchical nanoporous structure design that can be applied to binary, ternary, and quaternary metal alloys for various functional applications.

19.
J Immunol ; 199(9): 3042-3050, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-28954887

RESUMO

Myeloperoxidase (MPO) anti-neutrophil cytoplasmic Ab (ANCA)-associated vasculitis results from autoimmunity to MPO. IL-17A plays a critical role in generating this form of autoimmune injury but its cell of origin is uncertain. We addressed the hypothesis that IL-17A-producing γδ T cells are a nonredundant requisite in the development of MPO autoimmunity and glomerulonephritis (GN). We studied MPO-ANCA GN in wild type, αß, or γδ T cell-deficient (C57BL/6, ßTCR-/- , and δTCR-/- respectively) mice. Both T cell populations played important roles in the generation of autoimmunity to MPO and GN. Humoral autoimmunity was dependent on intact αß T cells but was unaffected by γδ T cell deletion. Following MPO immunization, activated γδ T cells migrate to draining lymph nodes. Studies in δTCR-/- and transfer of γδ T cells to δTCR-/- mice show that γδ T cells facilitate the generation of anti-MPO autoimmunity and GN. δTCR-/- mice that received IL-17A-/- γδ T cells demonstrate that the development of anti-MPO autoimmunity and GN are dependent on γδ T cell IL-17A production. Finally, transfer of anti-MPO CD4+ T cell clones to naive δTCR-/- and wild type mice with planted glomerular MPO shows that γδ T cells are also necessary for recruitment of anti-MPO αß CD4+ effector T cells. This study demonstrates that IL-17A produced by γδ T cells plays a critical role in the pathogenesis of MPO-ANCA GN by promoting the development of MPO-specific αß T cells.


Assuntos
Doenças Autoimunes/imunologia , Linfócitos T CD4-Positivos/imunologia , Glomerulonefrite/imunologia , Peroxidase/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Animais , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/genética , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/patologia , Autoanticorpos/genética , Autoanticorpos/imunologia , Doenças Autoimunes/genética , Doenças Autoimunes/patologia , Linfócitos T CD4-Positivos/patologia , Glomerulonefrite/genética , Glomerulonefrite/patologia , Interleucina-17/genética , Interleucina-17/imunologia , Camundongos , Camundongos Knockout , Peroxidase/genética , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/genética
20.
Clin Exp Nephrol ; 23(6): 807-813, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30809748

RESUMO

BACKGROUND: The impact of distance between donor and recipient hospitals on outcomes in cadaveric kidney transplantations is unknown. We investigated the association between inter-hospital distance and outcomes in cadaveric kidney transplantations in Japan. METHODS: We retrospectively analyzed 363 cadaveric kidney transplantations between 2002 and 2017 in Japan. Inter-hospital distance, graft transport time, total ischemic time (TIT), and graft survival were compared between our hospital and national transplantation cohort in Japan. Estimated glomerular filtration rate (eGFR) 1 month and 1 year after transplantation was compared between cadaveric and living-donor kidney transplantations in our hospitals. Additionally, inter-hospital distances among the seven geographical regions in Japan were assessed. RESULTS: There were 12 and 351 cadaveric kidney transplantations at our hospital and in Japan, respectively. Mean inter-hospital distance at our hospital (217 ± 121 km) was significantly longer than that of the national cohort (53 ± 80 km; P < 0.001). Mean TIT and graft survival for our hospital and national cohort were 539 ± 200 min and 91% and 491 ± 193 min and 81%, respectively. Mean eGFRs 1 year after cadaveric and living-donor transplantations at our hospitals were comparable (47 ± 16 vs. 47 ± 15 mL/min/1.73 m2). The comparison among seven regions in Japan indicated a regional difference in inter-hospital distance with an association between area (km2) and inter-hospital distance (km). CONCLUSIONS: Despite the longer inter-hospital distance at our hospital, TIT and transplant outcomes were acceptable in our cases. In addition, geographical inequity in graft allocation in Japan was suggested.


Assuntos
Isquemia Fria , Transplante de Rim/estatística & dados numéricos , Meios de Transporte/estatística & dados numéricos , Adulto , Idoso , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
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