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1.
Small ; 20(16): e2307175, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38032159

RESUMO

Cu2ZnSn(S,Se)4 (CZTSSe) thin film solar cells are an attractive choice for a bottom cell of the low-cost and environmental tandem solar cells with perovskite. However, the progress in developing efficient perovskite/CZTSSe tandem solar cells has been hindered by the lack of high performance of the CZTSSe bottom cell. Here, an efficient CZTSSe bottom cell is demonstrated by adopting a facile and effective CsF treatment process. It is found that the CsF treatment not only facilitates grain growth and improves phase homogeneity by suppressing the detrimental deep-level defects and secondary phases, but also induces larger band bending and stronger drift force at the P-N junction. As a result, the carrier extraction/transport can be effectively accelerated, while reducing the interfacial recombination. These combined effects eventually result in a significant performance enhancement from 8.38% to 10.20%. The CsF-treated CZTSSe solar cell is finally applied to the mechanically-stacked perovskite/CZTSSe 4-terminal tandem cell by coupling a semi-transparent perovskite top cell, which exhibits the highest reported tandem efficiency of 23.01%.

2.
FASEB J ; 37(8): e23104, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37486753

RESUMO

A new target that stimulates bone formation is needed to overcome limitations of current anti-osteoporotic drugs. Myokines, factors secreted from muscles, may modulate it. In this study, we investigated the role of aortic carboxypeptidase-like protein (ACLP), which is highly expressed in skeletal muscles, on bone formation. MC3T3-E1 cells and/or calvaria osteoblasts were treated with recombinant N-terminal mouse ACLP containing a signal peptide [rmACLP (N)]. The expression and secretion of ACLP were higher in skeletal muscle and differentiated myotube than in other tissues and undifferentiated myoblasts, respectively. rmACLP (N) increased bone formation, ALP activity, and phosphorylated p38 mitogen-activated protein (MAP) kinase in osteoblasts; reversal was achieved by pre-treatment with a TGF-ß receptor inhibitor. Under H2 O2 treatment, rmACLP (N) increased osteoblast survival, phosphorylated p38 MAP kinase, and the nuclear translocation of FoxO3a in osteoblasts. H2 O2 treatment caused rmACLP (N) to suppress its apoptotic, oxidative, and caspase-9 activities. rmACLP (N)-stimulated osteoblast survival was reversed by pre-treatment with a p38 inhibitor, a TGF-ß-receptor II blocking antibody, and a FoxO3a shRNA. Conditioned media (CM) from muscle cells stimulated osteoblast survival under H2 O2 treatment, in contrast to CM from ACLP knockdown muscle cells. rmACLP (N) increased the expressions of FoxO3a target anti-oxidant genes such as Sod2, Trx2, and Prx5. In conclusion, ACLP stimulated the differentiation and survival of osteoblasts. This led to the stimulation of bone formation by the activation of p38 MAP kinase and/or FoxO3a via TGF-ß receptors. These findings suggest a novel role for ACLP in bone metabolism as a putative myokine.


Assuntos
Carboxipeptidases , Proteínas Quinases p38 Ativadas por Mitógeno , Animais , Camundongos , Diferenciação Celular/fisiologia , Carboxipeptidases/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Osteogênese , Osteoblastos/metabolismo , Fosforilação
3.
Ecotoxicol Environ Saf ; 260: 115061, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37257343

RESUMO

The widely used plasticizer bisphenol A (BPA) is known as an endocrine-disrupting chemical (EDC). Many studies have shown that BPA contributes to diseases involving immune system alterations, but the underlying mechanisms have yet to be elucidated. We previously reported that BPA at concentration of 100 µM caused human B cell death in accordance with an increase in nuclear factor (erythroid-derived 2)-like 2(Nrf2) expression. Autophagy is a cellular process that degraded and recycles cytoplasmic constituents. Here, we investigated whether BPA induces autophagy through Nrf2, which is associated with regulation of B cell death using human WiL2-NS lymphoblast B cells. Then, cell viability was assessed by various assays using trypan blue, MTT or Celltiter glo luminescent substrate and DAPI. When WiL2-NS cells were treated with BPA, cell viability was decreased and LC3 autophagy cargo protein/puncta was increased. BPA-induced autophagy was confirmed by the modification of LC3 puncta formation or autophagy flux turnover with the treatment of hydroxychloroquine(HCQ), NH4Cl and PI3K inhibitors including 3-methyladenine(3-MA), LY294002 and wortmannin. BPA treatment increased the expression of autophagy-related gene(Atg)7 and Beclin1 as well as Nrf2 induced by the production of reactive oxygen species (ROS). The inhibition of autophagy with siAtg7 or siBeclin1 and Nrf2 depletion aggravated BPA-induced cell death. BPA enhanced the bound of Nrf2 to the specific region on Beclin1 and Atg7 promoter. Spleen tyrosine kinase(Syk) activity was enhanced in response to BPA treatment. Bay61-3606, Syk inhibitor, decreased LC3 and the expression of Atg7 and Beclin1, leading to the increase of BPA-induced B cell death. The results suggest that BPA-induced autophagy ameliorates human B cell death through Nrf2-mediated regulation of Atg7 and Beclin1 expression.


Assuntos
Fator 2 Relacionado a NF-E2 , Fosfatidilinositol 3-Quinases , Humanos , Proteína Beclina-1 , Fator 2 Relacionado a NF-E2/metabolismo , Autofagia , Morte Celular , Proteína 7 Relacionada à Autofagia
4.
World J Urol ; 39(3): 877-882, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32436073

RESUMO

PURPOSE: Colder seasons can aggravate lower urinary tract symptoms, especially an overactive bladder (OAB). This aspect has been extensively studied in men and rarely in women. We investigated whether colder seasons influence OAB-drug prescription rates (OAB-DPRs) in women. METHODS: Women aged > 18 years were selected from the Korean Health Insurance Review and Assessment Service-National Patient Sample data between 2012 and 2016. OAB-DPR was calculated according to age and seasonal groups. The prescription rates in summer (June, July, and August) and winter (January, February, and December) months were compared. Sub-analysis was performed according to age group. RESULTS: In total, 3,061,343 adult women were included. The overall OAB-DPR was 3.75% (114,940/3,061,343). Overall OAB-DPRs in summer and winter were 1.41% (43,090/3,061,343) and 1.54% (47,038/3,061,343), respectively (p < 0.001). Seasonal variations in OAB-DPRs differed by age group (p < 0.001): OAB-DPRs were significantly lower in winter than in summer months in women aged < 50 years (odds ratio 0.942; 95% confidence interval 0.918-0.967; p < 0.001), but significantly higher in winter than in summer months in women aged ≥ 50 years (odds ratio 1.153; 95% confidence interval 1.135-1.171; p < 0.001). CONCLUSION: In this study, a correlation was noted between OAB-DPR and seasons. OAB-DPRs were higher in the summer in women aged < 50 years and higher in the winter in women aged ≥ 50 years. Our findings suggest that female hormonal status may be involved in the contradictory effect of seasons on OAB symptoms.


Assuntos
Prescrições de Medicamentos/estatística & dados numéricos , Estações do Ano , Bexiga Urinária Hiperativa/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , República da Coreia
5.
Gerontology ; 67(5): 525-531, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33690236

RESUMO

BACKGROUND: Growth differentiation factor 15 (GDF15), induced by tissue inflammation and mitochondrial stress, has received significant attention as a biomarker of mitochondrial dysfunction and has been implicated in various age-related diseases. However, the association between circulating GDF15 and sarcopenia-associated outcomes in older adults remains to be established. AIM: To validate previous experimental data and to investigate the possible role of GDF15 in aging and muscle physiology in humans, this study examined serum GDF15 levels in relation to sarcopenia-related parameters in a cohort of older Asian adults. METHODS: Muscle mass and muscle function-related parameters, such as grip strength, gait speed, chair stands, and short physical performance battery score were evaluated by experienced nurses in 125 geriatric participants with or without sarcopenia. Sarcopenia was diagnosed using the Asian-specific cutoff points. Serum GDF15 levels were measured using an enzyme immunoassay kit. RESULTS: Serum GDF15 levels were not significantly different according to sarcopenia status, muscle mass, muscle strength, and physical performance and were not associated with the skeletal muscle index, grip strength, gait speed, time to complete 5 chair stands, and short physical performance battery score, regardless of adjustments for sex, age, and BMI. CONCLUSIONS: These findings indicate that the definite role of GDF15 on muscle metabolism observed in animal models might not be evident in humans and that elevated GDF15 levels might not predict the risk for sarcopenia, at least in older Asian adults.


Assuntos
Sarcopenia , Idoso , Animais , Estudos Transversais , Avaliação Geriátrica , Fator 15 de Diferenciação de Crescimento , Força da Mão , Humanos , Força Muscular , Músculo Esquelético , Sarcopenia/diagnóstico
6.
Int J Mol Sci ; 22(9)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33946862

RESUMO

Lumican, a ubiquitously expressed small leucine-rich proteoglycan, has been utilized in diverse biological functions. Recent experiments demonstrated that lumican stimulates preosteoblast viability and differentiation, leading to bone formation. To further understand the role of lumican in bone metabolism, we investigated its effects on osteoclast biology. Lumican inhibited both osteoclast differentiation and in vitro bone resorption in a dose-dependent manner. Consistent with this, lumican markedly decreased the expression of osteoclastogenesis markers. Moreover, the migration and fusion of preosteoclasts and the resorptive activity per osteoclast were significantly reduced in the presence of lumican, indicating that this protein affects most stages of osteoclastogenesis. Among RANKL-dependent pathways, lumican inhibited Akt but not MAP kinases such as JNK, p38, and ERK. Importantly, co-treatment with an Akt activator almost completely reversed the effect of lumican on osteoclast differentiation. Taken together, our findings revealed that lumican inhibits osteoclastogenesis by suppressing Akt activity. Thus, lumican plays an osteoprotective role by simultaneously increasing bone formation and decreasing bone resorption, suggesting that it represents a dual-action therapeutic target for osteoporosis.


Assuntos
Reabsorção Óssea/fisiopatologia , Lumicana/farmacologia , Osteoclastos/metabolismo , Osteogênese/fisiologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Fusão Celular , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Lumicana/fisiologia , Fator Estimulador de Colônias de Macrófagos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Osteogênese/efeitos dos fármacos , Osteoprotegerina/biossíntese , Ligante RANK/biossíntese , Ligante RANK/farmacologia , Proteínas Recombinantes/farmacologia
7.
BMC Geriatr ; 20(1): 420, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33087053

RESUMO

BACKGROUND: Apelin, an active endogenous peptide, has been recently receiving great attention as a promising target for antiaging intervention, primarily based on results from genetically altered mice. To validate previous experimental data and investigate the possible role of apelin in humans, in this study, we examined serum apelin level in relation to frailty and its associated parameters in a cohort of ambulatory, community-dwelling older adults. METHODS: Blood samples were collected from 80 participants who underwent a comprehensive geriatric assessment, and apelin level was measured using an enzyme immunoassay kit. Phenotypic frailty and deficit-accumulation frailty index (FI) were assessed using widely validated approaches, proposed by Fried and Rockwood groups, respectively. RESULTS: After adjustment for sex, age, and body mass index, serum apelin level was found to be not significantly different according to phenotypic frailty status (P = 0.550) and not associated with FI, grip strength, gait speed, time to complete 5 chair stands, and muscle mass (P = 0.433 to 0.982). To determine whether the association between serum apelin level and frailty has a threshold effect, we divided the participants into quartiles according to serum apelin level. However, there were no differences in terms of frailty-related parameters and the risk for frailty among the quartile groups (P = 0.248 to 0.741). CONCLUSIONS: The serum apelin level was not associated with both phenotypic frailty and functional parameters in older adults, despite its beneficial effects against age-related physiologic decline in animal models. Further large-scale longitudinal studies are necessary to understand the definite role of circulating apelin in frailty risk assessment.


Assuntos
Fragilidade , Idoso , Animais , Apelina , Estudos Transversais , Idoso Fragilizado , Fragilidade/diagnóstico , Avaliação Geriátrica , Humanos , Camundongos
8.
J Korean Med Sci ; 35(5): e61, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32030925

RESUMO

In December 2019, a viral pneumonia outbreak caused by a novel betacoronavirus, the 2019 novel coronavirus (2019-nCoV), began in Wuhan, China. We report the epidemiological and clinical features of the first patient with 2019-nCoV pneumonia imported into Korea from Wuhan. This report suggests that in the early phase of 2019-nCoV pneumonia, chest radiography would miss patients with pneumonia and highlights taking travel history is of paramount importance for early detection and isolation of 2019-nCoV cases.


Assuntos
Infecções por Coronavirus , Pneumonia Viral , Radiografia Torácica , Adulto , COVID-19 , China , Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/transmissão , Surtos de Doenças , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Anamnese , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/etiologia , Pneumonia Viral/transmissão , República da Coreia , Viagem
9.
Biochem Biophys Res Commun ; 514(3): 868-874, 2019 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-31084928

RESUMO

Axon guidance molecules, originally found to mediate the positioning of axons during nerve development, have been receiving great attention due to their critical roles in regulating bone metabolism. Recently, SLITs, another group of neuronal guidance proteins, were found to be significantly expressed in bone cells. Furthermore, we had provided experimental evidence that SLIT3 is an osteoclast-secreted coupling factor playing an osteoprotective role. Therefore, we hypothesized that SLIT2, a member of the SLIT family, may also affect bone homeostasis. SLIT2 suppressed osteoclast differentiation in a dose-dependent manner and in vitro bone resorption by more than 80%. Consistently, the expression of osteoclast differentiation markers, such as tartrate-resistant acid phosphatase (Trap) and calcitonin receptor (Ctr), was decreased by SLIT2. The migration and fusion of preosteoclasts were markedly reduced in the presence of SLIT2, suggesting that SLIT2 mainly functions in the early stage of osteoclastogenesis. SLIT2 suppressed Cdc42 activity among small GTPases, whereas Cdc42 overexpression almost completely reversed the SLIT2-mediated suppression of osteoclast differentiation. Among ROBO1-4, the SLIT receptors, ROBO1 and ROBO3 were known to be predominantly expressed in osteoclast lineages. A binding ELISA experiment in mouse bone marrow-derived macrophages showed that ROBO1, rather than ROBO3, was directly associated with SLIT2, and gene silencing with Robo1 siRNA blocked the SLIT2-mediated suppression of osteoclastogenesis. Taken together, our results indicated that SLIT2 inhibits osteoclastogenesis and the resultant bone resorption by decreasing Cdc42 activity, suggesting that this was a potential therapeutic target in metabolic bone diseases related to high bone turnover states.


Assuntos
Reabsorção Óssea/genética , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas do Tecido Nervoso/genética , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Osteogênese/genética , Proteína cdc42 de Ligação ao GTP/genética , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Reabsorção Óssea/metabolismo , Reabsorção Óssea/patologia , Reabsorção Óssea/prevenção & controle , Diferenciação Celular , Proliferação de Células , Fêmur/citologia , Fêmur/metabolismo , Regulação da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Proteínas do Tecido Nervoso/antagonistas & inibidores , Proteínas do Tecido Nervoso/metabolismo , Osteoblastos/citologia , Osteoclastos/patologia , Cultura Primária de Células , Células RAW 264.7 , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Receptores da Calcitonina/genética , Receptores da Calcitonina/metabolismo , Receptores Imunológicos/antagonistas & inibidores , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo , Transdução de Sinais , Fosfatase Ácida Resistente a Tartarato/genética , Fosfatase Ácida Resistente a Tartarato/metabolismo , Tíbia/citologia , Tíbia/metabolismo , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas Roundabout
10.
Biochem Biophys Res Commun ; 517(4): 749-754, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31395341

RESUMO

Recently, muscle has received much attention as an endocrine organ regulating other biological targets, including the pancreas, liver, and adipose tissue. Although there is a possibility that muscle-secreting factors biochemically affect bone metabolism in a paracrine manner, the net effects of myokines on the biology of osteoclasts and osteoblasts, particularly on bone mass in vivo, have not yet been thoroughly investigated. Therefore, we performed in vitro as well as animal experiments using conditioned media (CM) collected from C2C12 myoblast and myotube cultures to better understand the interactions between muscle and bone. Compared with non-CM (i.e., control) and myoblast CM, myotube CM markedly inhibited in vitro bone resorption through the suppression of osteoclast differentiation and resorptive activity of individual osteoclasts. Consistently, the expressions of osteoclast differentiation markers, such as tartrate-resistant acid phosphatase (Trap) and calcitonin receptor (Ctr), decreased with myotube CM. Myotube CM significantly stimulated preosteoblast viability and migration and reduced apoptosis, thereby resulting in an increase in calvaria bone formation. Importantly, systemic treatment with myotube CM for 4 weeks increased bone per tissue volume by 30.7% and 19.6% compared with control and myoblast CM, respectively. These results support the hypothesis that muscle plays beneficial roles in bone health via secretion of anabolic factors, in addition to mechanical stimuli, and importantly indicate that muscle-derived factors can be potential therapeutic targets against metabolic bone diseases.


Assuntos
Citocinas/farmacologia , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Animais , Reabsorção Óssea/patologia , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Feminino , Camundongos Endogâmicos C57BL , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Tamanho do Órgão/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteoblastos/patologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/patologia , Osteogênese/efeitos dos fármacos
11.
Luminescence ; 34(8): 838-845, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31313470

RESUMO

Aluminium oxide (Al2 O3 ) has widely been used for catalysts, insulators, and composite materials for diverse applications. Herein, we demonstrated if γ-Al2 O3 was useful as a luminescence support material for europium (Eu) (III) activator ion. The hydrothermal method and post-thermal treatment at 800°C were employed to synthesize Eu(III)-doped γ-Al2 O3 nanofibre structures. Luminescence characteristics of Eu(III) ions in Al2 O3 matrix were fully understood by taking 2D and 3D-photoluminescence imaging profiles. Various sharp emissions between 580 to 720 nm were assigned to the 5 D0 →7 FJ (J = 0, 1, 2, 3, 4) transitions of Eu(III) activators. On the basis of X-ray diffraction crystallography, Auger elemental mapping and the asymmetry ratio, Eu(III) ions were found to be well doped into the γ-Al2 O3 matrix at a low (1 mol%) doping level. A broad emission at 460 nm was substantially increased upon higher (2 mol%) Eu(III) doping due to defect creation. The first 3D photoluminescence imaging profiles highlight detailed understanding of emission characteristics of Eu(III) ions in Al oxide-based phosphor materials and their potential applications.


Assuntos
Óxido de Alumínio/química , Substâncias Luminescentes/química , Medições Luminescentes , Nanofibras/química , Európio/química , Tamanho da Partícula , Processos Fotoquímicos , Propriedades de Superfície
12.
Nanotechnology ; 29(22): 22LT01, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29513275

RESUMO

The practical applicability of electronic devices is largely determined by the reliability of field effect transistors (FETs), necessitating constant searches for new and better-performing semiconductors. We investigated the stress-induced degradation of MoS2 multilayer FETs, revealing a steady decrease of drain current by 56% from the initial value after 30 min. The drain current recovers to the initial state when the transistor is completely turned off, indicating the roles of soft-traps in the apparent degradation. The noise current power spectrum follows the model of carrier number fluctuation-correlated mobility fluctuation (CNF-CMF) regardless of stress time. However, the reduction of the drain current was well fitted to the increase of the trap density based on the CNF-CMF model, attributing the presence of the soft-type traps of dielectric oxides to the degradation of the MoS2 FETs.

13.
Proc Natl Acad Sci U S A ; 110(33): 13546-51, 2013 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-23898190

RESUMO

Sirtuin 2 (SIRT2) is a sirtuin family deacetylase that directs acetylome signaling, protects genome integrity, and is a murine tumor suppressor. We show that SIRT2 directs replication stress responses by regulating the activity of cyclin-dependent kinase 9 (CDK9), a protein required for recovery from replication arrest. SIRT2 deficiency results in replication stress sensitivity, impairment in recovery from replication arrest, spontaneous accumulation of replication protein A to foci and chromatin, and a G2/M checkpoint deficit. SIRT2 interacts with and deacetylates CDK9 at lysine 48 in response to replication stress in a manner that is partially dependent on ataxia telangiectasia and Rad3 related (ATR) but not cyclin T or K, thereby stimulating CDK9 kinase activity and promoting recovery from replication arrest. Moreover, wild-type, but not acetylated CDK9, alleviates the replication stress response impairment of SIRT2 deficiency. Collectively, our results define a function for SIRT2 in regulating checkpoint pathways that respond to replication stress through deacetylation of CDK9, providing insight into how SIRT2 maintains genome integrity and a unique mechanism by which SIRT2 may function, at least in part, as a tumor suppressor protein.


Assuntos
Pontos de Checagem do Ciclo Celular/fisiologia , Quinase 9 Dependente de Ciclina/metabolismo , Replicação do DNA/fisiologia , Sirtuína 2/metabolismo , Acetilação , Animais , Western Blotting , Linhagem Celular , Cromatografia Líquida , Ensaio de Unidades Formadoras de Colônias , Imunofluorescência , Humanos , Camundongos , Proteína de Replicação A/metabolismo , Espectrometria de Massas em Tandem
14.
Nano Lett ; 15(7): 4578-84, 2015 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-26087437

RESUMO

Si nanowire (Si-NW) based thin-film transistors (TFTs) have been considered as a promising candidate for next-generation flexible and wearable electronics as well as sensor applications with high performance. Here, we have fabricated ambipolar Schottky-barrier (SB) TFTs consisting of a parallel array of Si-NWs and performed an in-depth study related to their electrical performance and operation mechanism through several electrical parameters extracted from the channel length scaling based method. Especially, the newly suggested current-voltage (I-V) contour map clearly elucidates the unique operation mechanism of the ambipolar SB-TFTs, governed by Schottky-junction between NiSi2 and Si-NW. Further, it reveals for the first-time in SB based FETs the important internal electrostatic coupling between the channel and externally applied voltages. This work provides helpful information for the realization of practical circuits with ambipolar SB-TFTs that can be transferred to different substrate technologies and applications.

15.
BMC Infect Dis ; 15: 381, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26392175

RESUMO

BACKGROUND: Serial interferon-gamma-release-assay (IGRA) result can show variance due to within-subject variation and difference in host immune status, and may be affected by latent tuberculosis infection (LTBI) treatment. We aimed to know the changes in QFT-IT (QuantiFERON-TB Gold In-Tube) results measured at a 4 month interval in end stage renal disease patients and whether these changes were influenced by dialysis method or LTBI treatment. METHODS: We prospectively performed serial QFT-IT tests at 4 month interval in 93 end stage renal disease (ESRD) patients on HD (hemodialysis) or PD (peritoneal dialysis). LTBI treatment was given to 18 of 39 patients with initial positive QFT-IT result. Agreement between the two results was estimated for all 93 patients and reversion rates were estimated among the 39 patients with initial positive QFT-IT. RESULTS: Positive QFT-IT at the first and 2(nd) tests were 41.9 and 34.4 %, respectively. The concordance rate between baseline QFT-IT and 2(nd) QFT in 93 ESRD patients was excellent (90.3 %, kappa = 0.80, p < 0.001). Agreement between the first QFT-IT and 2(nd) QFT-IT in HD (95.3 %, kappa = 0.91, p < 0.001) was higher than in PD patients (86.0 %, kappa = 0.69, p < 0.001). Among all ESRD patients, the odds of reversion of QFT-IT was not different in those who were, or were not treated for LTBI [odds ratio = 2.3 (0.5-11.4), p = 0.43]. CONCLUSIONS: In a group of 93 dialyzed ESRD patients 8.6 % showed reversion of initial positive QFT to negative within 4 months. Reversion seemed not to be associated with LTBI treatment. Further study with larger numbers of patients is needed to investigate the variation of QFT-IT tests in dialyzed ESRD patients.


Assuntos
Testes de Liberação de Interferon-gama , Interferon gama/metabolismo , Tuberculose Latente/diagnóstico , Adulto , Idoso , Povo Asiático , Demografia , Feminino , Humanos , Falência Renal Crônica/complicações , Tuberculose Latente/complicações , Tuberculose Latente/metabolismo , Masculino , Pessoa de Meia-Idade , Diálise Peritoneal , Estudos Prospectivos , Diálise Renal , Reprodutibilidade dos Testes , República da Coreia
16.
Clin Hypertens ; 30(1): 6, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38424656

RESUMO

BACKGROUND: Improving adherence to antihypertensive medication (AHM) is a key challenge in hypertension management. This study aimed to assess the impact of ambulatory blood pressure monitoring (ABPM) on AHM adherence. METHODS: We utilized the Korean National Health Insurance Service database. Among patients newly diagnosed with hypertension who started AHM between July 2010 and December 2013, we compared clinical characteristics and adherence between 28,116 patients who underwent ABPM prior to starting AHM and 118,594 patients who did not undergo ABPM. Good adherence was defined as a proportion of days covered (PDC) of 0.8 or higher. RESULTS: The total study population was 146,710, with a mean age of 50.5 ± 6.4 years; 44.3% were female. Co-morbidities were noted in 4.2%. About a third of patients (33.1%) showed good adherence. The ABPM group had a notably higher PDC (total PDC: 0.64 ± 0.35 vs. 0.45 ± 0.39; P < 0.001), irrespective of the number of medications, dosing frequency, or prescription duration. After adjusting for significant clinical variables, ABPM was still closely linked with good adherence (odds ratio, 2.35; 95% confidence interval, 2.28-2.41; P < 0.001). CONCLUSIONS: In newly diagnosed hypertension, undergoing ABPM prior to AHM prescription appears to enhance adherence to AHM. The exact mechanisms driving this association warrant further exploration.

17.
Bone ; 179: 116959, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37956822

RESUMO

In vitro and animal experiments demonstrated that lumican exerts anabolic effects on bone and muscle by stimulating osteoblastogenesis, suppressing osteoclastogenesis and increasing myogenesis. However, the relationship between circulating lumican and musculoskeletal phenotypes in humans remains unclear. We aimed to analyze the relationship between serum lumican levels and osteosarcopenia in older adults. Blood samples were collected from 134 participants (age: 65 years and older) who underwent comprehensive assessment of bone and muscle phenotypes. Osteoporosis and sarcopenia were diagnosed based on World Health Organization and Asian consensus guidelines, respectively. Osteosarcopenia was defined as the simultaneous presence of osteoporosis and sarcopenia. After adjusting for sex, age, and body mass index, older adults with osteosarcopenia had 20.2 % lower serum lumican levels than those without (P = 0.010). The odds ratio (OR) for osteosarcopenia per standard deviation decrease in serum lumican level was 4.17 (P = 0.003). Consistently, higher serum lumican levels were correlated with higher bone mass at all measured sites (P = 0.004 to 0.045) and higher grip strength (P = 0.023). Furthermore, participants in the lowest tertile (T1) had 7.56-fold higher OR for osteosarcopenia (P = 0.024) than those in the highest lumican tertile (T3). In conclusion, these findings clinically validate previous experimental data showing the musculoskeletal protective effects of lumican and suggest that blood lumican levels could be used as a potential biomarker to assess the risk of not only osteosarcopenia but also osteoporosis or sarcopenia in older adults.


Assuntos
Osteoporose , Sarcopenia , Idoso , Humanos , Biomarcadores , Força da Mão/fisiologia , Lumicana , Osteoporose/diagnóstico , Sarcopenia/diagnóstico
18.
Qual Life Res ; 22(2): 431-6, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22476571

RESUMO

PURPOSE: (1) To translate original English Cancer Therapy Satisfaction Questionnaire (CTSQ) into Korean and perform validation, (2) to compare CTSQ domains of expectations of therapy (ET), feelings about side effects (FSE), and satisfaction with therapy (SWT) by cancer therapy type. METHODS: Cross-cultural adaptation was performed according to guidelines: translation, back translation, focus-group, and field test. We performed validation with internal consistency by Cronbach's alpha and construct validity by exploratory factor analysis (EFA) with varimax rotation method. We compared each CTSQ domain between traditional Korean Medicine (TKM) and integrative cancer therapy (ICT) of combining western and TKM by two-sample t test. RESULTS: Cross-cultural adaptation produced no major modifications in the items and domains. A total of 102 outpatients were participated. Mean age was 51.9 ± 12.4. Most were stage 4 (74.4 %) cancer. Mean scores of ET, FSE, and SWT were 81.2 ± 15.7, 79.5 ± 22.9, and 75.7 ± 14.8, respectively. Cronbach's alpha of ET, FSE, and SWT were 0.86, 0.78, and 0.74, respectively. EFA loaded items on the three domains, which is very close to that of the original CTSQ. ET and SWT was similar, but FSE was significantly higher in TKM than ICT (87.5 ± 19.3 vs. 74.9 ± 23.5; p = 0.0054). CONCLUSIONS: Cross-cultural adaptation was successful, and the adapted Korean CTSQ demonstrated good internal consistency and construct validity. Similar expectation and satisfaction was shown between the two types of therapy, but patient's reported feelings about side effects was significantly lower in patients receiving TKM than receiving ICT. Korean version of CTSQ can be used to evaluate Korean cancer patient's experiences receiving various cancer therapy types.


Assuntos
Neoplasias/psicologia , Neoplasias/terapia , Satisfação do Paciente , Psicometria , Qualidade de Vida , Inquéritos e Questionários , Idoso , Povo Asiático/psicologia , Comparação Transcultural , Análise Fatorial , Feminino , Grupos Focais , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Reprodutibilidade dos Testes , República da Coreia , Traduções
19.
J Nanosci Nanotechnol ; 13(9): 6203-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24205629

RESUMO

Biological materials with surface-active proteins can be genetically modified to bind target materials. In particular, filamentous-shaped M13 bacteriophages (M13 phage) are attractive scaffolds for functional nanostructures due to their highly ordered protein-coat surface. This paper demonstrates a simple method for fabricating silica nanocables along a modified M13 phage. The M13 phage was genetically engineered to display the amino acid serine on the surface to provide hydroxyl groups for a sol-gel reaction. This M13 phage mutant offers homogeneous molecular templates for forming silica coated coaxial nanocables. Silica shell formation was confirmed by transmission electron microscopy (TEM) and electron dispersive X-ray (EDX) analysis. The core-shell structures were clearly distinguishable in the TEM analysis, and the synthesized shells were observed by EDX analysis. In addition, we investigated the adsorption properties of M13 phages on the pretreated substrate as a function of concentration. The effect of the relative concentration of M13 phages on the substrate was observed by using atomic force microscopy (AFM). We also fabricated top electrodes on the extremely dense network for measuring electrical properties of the M13 phage. The experimental DC measurement indicated that the wild-type phage has very low electrical conductance, similar to insulating material.


Assuntos
Bacteriófago M13/química , Nanoestruturas , Dióxido de Silício/química , Microscopia Eletrônica de Transmissão , Espectrometria por Raios X
20.
ACS Appl Mater Interfaces ; 15(6): 8298-8304, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36740775

RESUMO

Junctionless transistors are suitable for sub-3 nm applications because of their extremely simple structure and high electrical performance, which compensate for short-channel effects. Two-dimensional semiconductor transition-metal dichalcogenide materials, such as MoS2, may also resolve technical and fundamental issues for Si-based technology. Here, we present the first junctionless electric-double-layer field-effect transistor with an electrostatically highly doped 5 nm thick MoS2 channel. A double-gated MoS2 transistor with an ionic-liquid top gate and a conventional bottom gate demonstrated good transfer characteristics with a 104 on-off current ratio, a 70 mV dec-1 subthreshold swing at a 0 V bottom-gate bias, and drain-current versus top-gate-voltage characteristics were shifted left significantly with increasing bottom-gate bias due to an electrostatically increased overall charge carrier concentration in the MoS2 channel. When a bottom-gate bias of 80 V was applied, a shoulder and two clear peak features were identified in the transconductance and its derivative, respectively; this outcome is typical of Si-based junctionless transistors. Furthermore, the decrease in electron mobility induced by a transverse electric field was reduced with increasing bottom-gate bias. Numerical simulations and analytical models were used to support these findings, which clarify the operation of junctionless MoS2 transistors with an electrostatically highly doped channel.

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