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1.
Small Methods ; : e2400284, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651527

RESUMO

Perovskite materials that aren't stable during the oxygen evolution reaction (OER) are unsuitable for anion-exchange membrane water electrolyzers (AEMWE). But through manipulating their electronic structures, their performance can further increase. Among the first-row transition metals, nickel and iron are widely recognized as prominent electrocatalysts; thus, the researchers are looking into how combining them can improve the OER. Recent research has actively explored the design and study of heterostructures in this field, showcasing the dynamic exploration of innovative catalyst configurations. In this study, a heterostructure is used to manipulate the electronic structure of LaNiO3 (LNO) to improve both OER properties and durability. Through adsorbing iron onto the LNO (LNO@Fe) as γ iron oxyhydroxide (γ-FeOOH), the binding energy of nickel in the LNO exhibited negative shifts, inferring nickel movement toward the metallic state. Consequently, the electrochemical properties of LNO@Fe are further improved. LNO@Fe showed excellent performance (1.98 A cm-2, 1 m KOH, 50 °C at 1.85 V) with 84.1% cell efficiency in AEMWE single cells, demonstrating great improvement relative to LNO. The degradation for the 850 h durability analysis of LNO@Fe is ≈68 mV kh-1, which is ≈58 times less than that of LNO.

2.
Adv Healthc Mater ; 13(15): e2303581, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38386698

RESUMO

Abnormal oculomotor movements are known to be linked to various types of brain disorders, physical/mental shocks to the brain, and other neurological disorders, hence its monitoring can be developed into a simple but effective diagnostic tool. To overcome the limitations in the current eye-tracking system and electrooculography, a piezoelectric arrayed sensor system is developed using single-crystalline III-N thin-film transducers, which offers advantages of mechanical flexibility, biocompatibility, and high electromechanical conversion, for continuous monitoring of oculomotor movements by skin-attachable, safe, and highly sensitive sensors. The flexible piezoelectric eye movement sensor array (F-PEMSA), consisting of three transducers, is attached to the face temple area where it can be comfortably wearable and can detect the muscles' activity associated with the eye motions. Output voltages from upper, mid, and lower sensors (transducers) on different temple areas generate discernable patterns of output voltage signals with different combinations of positive/negative signs and their relative magnitudes for the various movements of eyeballs including 8 directional (lateral, vertical, and diagonal) and two rotational movements, which enable various types of saccade and pursuit tests. The F-PEMSA can be used in clinical studies on the brain-eye relationship to evaluate the functional integrity of multiple brain systems and cognitive processes.


Assuntos
Movimentos Oculares , Humanos , Movimentos Oculares/fisiologia , Dispositivos Eletrônicos Vestíveis , Monitorização Fisiológica/instrumentação , Monitorização Fisiológica/métodos , Eletroculografia/instrumentação , Eletroculografia/métodos
3.
Nat Commun ; 11(1): 3823, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32732934

RESUMO

An accurate extraction of physiological and physical signals from human skin is crucial for health monitoring, disease prevention, and treatment. Recent advances in wearable bioelectronics directly embedded to the epidermal surface are a promising solution for future epidermal sensing. However, the existing wearable bioelectronics are susceptible to motion artifacts as they lack proper adhesion and conformal interfacing with the skin during motion. Here, we present ultra-conformal, customizable, and deformable drawn-on-skin electronics, which is robust to motion due to strong adhesion and ultra-conformality of the electronic inks drawn directly on skin. Electronic inks, including conductors, semiconductors, and dielectrics, are drawn on-demand in a freeform manner to develop devices, such as transistors, strain sensors, temperature sensors, heaters, skin hydration sensors, and electrophysiological sensors. Electrophysiological signal monitoring during motion shows drawn-on-skin electronics' immunity to motion artifacts. Additionally, electrical stimulation based on drawn-on-skin electronics demonstrates accelerated healing of skin wounds.


Assuntos
Monitorização Fisiológica/instrumentação , Sistemas Automatizados de Assistência Junto ao Leito , Pele/fisiopatologia , Dispositivos Eletrônicos Vestíveis , Artefatos , Estimulação Elétrica , Epiderme/fisiologia , Humanos , Movimento (Física) , Semicondutores , Auxiliares Sensoriais , Pele/lesões , Cicatrização
4.
Sci Adv ; 4(6): eaap9360, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29951583

RESUMO

Highly active and durable bifunctional oxygen electrocatalysts have been of pivotal importance for renewable energy conversion and storage devices, such as unitized regenerative fuel cells and metal-air batteries. Perovskite-based oxygen electrocatalysts have emerged as promising nonprecious metal bifunctional electrocatalysts, yet their catalytic activity and stability still remain to be improved. We report a high-performance oxygen electrocatalyst based on a triple perovskite, Nd1.5Ba1.5CoFeMnO9-δ (NBCFM), which shows superior activity and durability for oxygen electrode reactions to single and double perovskites. When hybridized with nitrogen-doped reduced graphene oxide (N-rGO), the resulting NBCFM/N-rGO catalyst shows further boosted bifunctional oxygen electrode activity (0.698 V), which surpasses that of Pt/C (0.801 V) and Ir/C (0.769 V) catalysts and which, among the perovskite-based electrocatalysts, is the best activity reported to date. The superior catalytic performances of NBCFM could be correlated to its oxygen defect-rich structure, lower charge transfer resistance, and smaller hybridization strength between O 2p and Co 3d orbitals.

5.
Nano Lett ; 15(4): 2350-7, 2015 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-25730382

RESUMO

Most of the existing flexible lithium ion batteries (LIBs) adopt the conventional cofacial cell configuration where anode, separator, and cathode are sequentially stacked and so have difficulty in the integration with emerging thin LIB applications, such as smart cards and medical patches. In order to overcome this shortcoming, herein, we report a coplanar cell structure in which anodes and cathodes are interdigitatedly positioned on the same plane. The coplanar electrode design brings advantages of enhanced bending tolerance and capability of increasing the cell voltage by in series-connection of multiple single-cells in addition to its suitability for the thickness reduction. On the basis of these structural benefits, we develop a coplanar flexible LIB that delivers 7.4 V with an entire cell thickness below 0.5 mm while preserving stable electrochemical performance throughout 5000 (un)bending cycles (bending radius = 5 mm). Also, even the pouch case serves as barriers between anodes and cathodes to prevent Li dendrite growth and short-circuit formation while saving the thickness. Furthermore, for convenient practical use wireless charging via inductive electromagnetic energy transfer and solar cell integration is demonstrated.

6.
J Neurogastroenterol Motil ; 16(3): 315-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20680171

RESUMO

Eosinophilic esophagitis (EoE) is a disorder characterized by isolated eosinophilic infiltration of the esophagus with esophageal symptoms. Although some patients with EoE are related to food hypersensitivity, it is hard to identify causative foods. This report describes a case of EoE with dysphagia. A 28-year-old man presented with dysphagia and substernal discomfort for 15 days. He had taken a protein complex for 2 months. Endoscopy showed several linear furrows and multiple mucosal nodularities on the lower and mid esophagus, and the biopsies of esophagus revealed marked eosinophil infiltration in the mucosa. The skin testing for the protein complex was positive. The patient was successfully treated with withholding treatment.

7.
World J Gastroenterol ; 14(32): 5051-8, 2008 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-18763289

RESUMO

AIM: To evaluate the efficacy of colonoscopy follow-up after short-term anti-tuberculosis treatment in patients with nonspecific ulcers on ileocecal areas being suspicious of tuberculous colitis. METHODS: We prospectively analyzed the colonoscopic findings before and after short term anti-tuberculosis treatment in 18 patients with nonspecific ulcers on the ileocecal area and compared them with 7 patients of confirmed tuberculous colitis by acid-fast bacilli or caseating granuloma on colonic biopsy. RESULTS: Mean duration for short-term follow-up was 107.3 d with combined chemotherapy containing isoniazid, rifampicin, ethambutol and pyrazinamide. Seven patients with tuberculous colitis showed complete healing of active ulcers after short-term medication. After short-term anti-tuberculosis treatment, follow-up colonoscopy findings divided 18 patients with nonspecific ulcers into two groups by ulcer state. One is the "suspicious tuberculous colitis group" showing healing of ulcers and erosions and another is the "suspicious inflammatory bowel disease group" showing active ulcers with or without aggravation of the lesion. Finally, all 9 of the "suspicious tuberculous colitis group" were diagnosed as tuberculous colitis showing no recurrence of ulcers after termination of 9 mo of anti-tuberculosis medication. Patients of the "suspicious inflammatory bowel disease group" were finally diagnosed as Crohn's disease or nonspecific colonic ulcers during long-term follow up. CONCLUSION: Follow-up colonoscopy shows a healing stage ulcer or scarring change without an active ulcer with just 2 mo to 3 mo of medication in patients with tuberculous colitis. Colonoscopy follow-up after short term anti-tuberculosis trial in patients with nonspecific ulcers on the ileocecal area is valuable in making early differential diagnosis of tuberculous colitis.


Assuntos
Antituberculosos/uso terapêutico , Colonoscopia , Tuberculose Gastrointestinal/tratamento farmacológico , Tuberculose Gastrointestinal/patologia , Adulto , Biópsia , Estudos de Casos e Controles , Ceco/microbiologia , Ceco/patologia , Colite/tratamento farmacológico , Colite/microbiologia , Colite/patologia , Feminino , Seguimentos , Humanos , Íleo/microbiologia , Íleo/patologia , Masculino
8.
J Gastroenterol Hepatol ; 23(6): 888-93, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18466289

RESUMO

BACKGROUND AND AIM: Some people have a fatty liver despite having low visceral fat and a low body mass index (BMI). We investigated whether fat distribution, especially thigh subcutaneous fat and thigh intramuscular fat, is associated with non-alcoholic fatty liver disease (NAFLD). METHODS: The patients consisted of 408 men and women. NAFLD was defined by an ultrasound scan and excluded other liver diseases. Visceral, subcutaneous abdominal, intramuscular, and subcutaneous thigh adipose tissue was measured by computed tomography. RESULTS: The frequency of NAFLD decreased over a quartile of thigh fat independently of BMI in the female patients. Additional adjustments for age and visceral fat area did not change the results. This finding was not observed in the male patients. To investigate the relationship between each fat distribution and NAFLD, we performed a logistic regression analysis. Fat distribution was divided into four groups: visceral fat, abdominal subcutaneous fat, thigh subcutaneous fat, and thigh intramuscular fat. All four fat components were chosen as variables for the regression model. Age, BMI, and the homeostasis model assessment (HOMA) index were then adjusted successively. A larger subcutaneous fat area was negatively associated with NAFLD after adjustment for visceral fat and abdominal subcutaneous fat areas in women, but not in men. It did not change even after age adjustment, BMI, and the HOMA index. CONCLUSION: Low femoral subcutaneous fat amounts were shown to be independently associated with fatty liver disease in women. These results show the importance of accurate measurements of other regional body compositions as well as visceral fat amounts when investigating NAFLD.


Assuntos
Distribuição da Gordura Corporal , Fígado Gorduroso/diagnóstico por imagem , Músculo Esquelético , Gordura Subcutânea , Coxa da Perna , Gordura Abdominal , Adulto , Índice de Massa Corporal , Fígado Gorduroso/diagnóstico , Feminino , Hospitais de Ensino , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Fatores de Risco , Ultrassonografia
9.
World J Gastroenterol ; 13(22): 3141-3, 2007 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-17589935

RESUMO

Intrahepatic cholangiocarcinoma is a malignant neoplasm arising from the biliary epithelium, which frequently invades adjacent organs or metastasizes to other visceral organs such as the lungs, bones, adrenals, and brain. However, distant skeletal muscle metastasis of cholangiocarcinoma has never been described before to the best of our knowledge and, furthermore, Budd-Chiari syndrome secondary to intrahepatic cholangiocarcinoma is also extremely rare. Here we present the first case overall of distant muscle metastasis from intrahepatic cholangiocarcinoma presenting as Budd-Chiari syndrome. A 44-year-old man admitted to the hospital with complaints of abdominal distension, edema of both legs, back pain and anorexia of 30 d' duration. Computed tomography and ultrasonography-guided percutaneous muscle biopsy established intrahepatic cholangiocarcinoma with disseminated thrombosis from inferior vena cava to bilateral iliac and femoral veins, and multiple skeletal muscle metastases in bilateral buttock and erector spinal muscle.


Assuntos
Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos , Síndrome de Budd-Chiari/diagnóstico , Colangiocarcinoma/diagnóstico , Colangiocarcinoma/secundário , Neoplasias Musculares/diagnóstico , Neoplasias Musculares/secundário , Adulto , Biópsia , Síndrome de Budd-Chiari/patologia , Diagnóstico Diferencial , Veia Femoral/patologia , Humanos , Veia Ilíaca/patologia , Masculino , Músculo Esquelético/patologia , Trombose/patologia
10.
Korean J Gastroenterol ; 49(5): 327-30, 2007 May.
Artigo em Coreano | MEDLINE | ID: mdl-17525521

RESUMO

Although a large number of studies have reported the causes of the exacerbation of ulcerative colitis (UC), the effect of influenza vaccination on the relapse of UC has not been reported. We experienced a case of prompt exacerbation of quiescent UC due to influenza vaccination. A 39-year-old woman was diagnosed as UC 4-years ago and was well controlled with oral mesalazine. She experienced abdominal pain and frequent bowel movements with hematochezia 3 days after the vaccination. On admission, laboratory findings showed elevated erythrocyte sedimentation rate and C-reactive protein. Sigmoidoscopy showed marked edematous mucosa on rectum and sigmoid colon with fine ulceration and spontaneous bleeding. She recovered from the exacerbation of UC after steroid treatment. Vaccination should be administered to the patients with inflammatory bowel disease with the caution of its possible side effects.


Assuntos
Colite Ulcerativa/diagnóstico , Colite Ulcerativa/etiologia , Vacinas contra Influenza/efeitos adversos , Adulto , Sedimentação Sanguínea , Proteína C-Reativa/análise , Colite Ulcerativa/diagnóstico por imagem , Feminino , Humanos , Vacinas contra Influenza/administração & dosagem , Recidiva , Sigmoidoscopia , Tomografia Computadorizada por Raios X
11.
Int Immunol ; 17(12): 1525-31, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16263754

RESUMO

To elucidate the role of Toll-like receptor 9 (TLR9) activation along with the intracellular signaling pathways triggered by CpG DNA in CD34+ cells, we investigated whether synthetic oligodeoxynucleotides (ODNs), containing unmethylated CpG motifs, could induce IL-8 expression in CD34+ cells through mitogen-activated protein kinase (MAPK) or nuclear factor-kappaB (NF-kappaB) pathway. We demonstrated evidence for the first time that CD34+ cells constitutively expressed TLR9. Exposure of the cells to CpG ODN resulted in a time- and dose-dependent increase of IL-8 expression, and activation of phosphorylated ERK1/2 and phosphorylated p38. In addition, CpG ODN stimulated AP-1, but not NF-kappaB, signals. Moreover, inhibitors of MAPK (U0126 and SB203580) significantly reduced the IL-8 production, while the inhibition of NF-kappaB (pyrrolidinedithiocarbamate and retrovirus containing dominant-negative IkappaB alpha plasmid) did not affect the IL-8 expression increased by CpG ODN. Moreover, co-stimulation with LPS and CpG synergistically up-regulates IL-8 in CD34+ cells. These results suggest that CpG DNA, acting on TLR9, activates CD34+ cells to express IL-8 through MAPK-dependent and NF-kappaB-independent pathways.


Assuntos
Sangue Fetal/imunologia , Sequência Rica em GC/imunologia , Células-Tronco Hematopoéticas/imunologia , Interleucina-8/biossíntese , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Oligodesoxirribonucleotídeos/farmacologia , Antígenos CD34/metabolismo , Butadienos/farmacologia , Células Cultivadas , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Sangue Fetal/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Células-Tronco Hematopoéticas/citologia , Humanos , Imidazóis/farmacologia , Sistema de Sinalização das MAP Quinases/imunologia , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Nitrilas/farmacologia , Oligodesoxirribonucleotídeos/imunologia , Piridinas/farmacologia , Receptor Toll-Like 9/imunologia
12.
Korean J Gastroenterol ; 44(4): 217-23, 2004 Oct.
Artigo em Coreano | MEDLINE | ID: mdl-15505434

RESUMO

BACKGROUND/AIMS: Eosinophilic gastroenteritis (EG) is an uncommon disease with various gastrointestinal symptoms characterized by eosinophilic infiltration. Its incidence increases recently. We investigated the clinicopathologic features of the patients with EG. METHODS: Between January 1970 and July 2003, a total of 28 cases of EG have been reported. By adding 3 cases diagnosed in the Eulji Hospital, we evaluated the 31 cases of EG for the symptoms, laboratory findings, histologic findings, method of treatment, and allergic history. RESULTS: The incidence increased during 1990s. The predominant site of the eosinophilic infiltration was mucosa in 10 cases, muscularis in 5 cases, and subserosa in 5 cases. The remaining 11 patients had the EG in two sites. The most frequently affected organ was small intestine (12 patients), but there were 12 cases which more than two organs involved. Melena and hematochezia were dominant findings in the patients whose infiltration occurred in mucosa. On the other hand, ascites was a dominant finding in the cases that infiltration occurred in subserosa or involving over 2 layers. There was no difference in eosinophilia, clinical symptoms, and duration between two groups according to the symptom duration for less or more than 30 days. Additionally, seven patients had allergic histories. Peripheral eosinophilia was found in 24 cases. There was no recurrence of EG after the treatment. CONCLUSIONS: Our retrospective studies about EG reported in Korea could not clarify whether EG is related to allergy. Recently, the occurrence of EG is increasing and it is frequently involved in young men. The most apparent finding include peripheral eosinophilia. There is no significant clinical feature which is consistent with Klein's classification, though blood loss was more common in mucosal type and ascites was more common in serosal type and in case above two layers.


Assuntos
Eosinofilia/diagnóstico , Gastroenterite/diagnóstico , Adolescente , Adulto , Idoso , Eosinofilia/complicações , Feminino , Gastroenterite/complicações , Humanos , Masculino , Pessoa de Meia-Idade
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