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1.
Angew Chem Int Ed Engl ; 61(24): e202201847, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35304803

RESUMO

A new class of polymeric hole-transport materials (HTMs) are explored by inserting a two-dimensionally conjugated fluoro-substituted pyrene into thiophene and selenophene polymeric chains. The broad conjugated plane of pyrene and "Lewis soft" selenium atoms not only enhance the π-π stacking of HTM molecules greatly but also render a strong interaction with the perovskite surface, leading to an efficient charge transport/transfer in both the HTM layer and the perovskite/HTM interface. Note that fluorine substitution adjacent to pyrene boosts the stacking of HTMs towards a more favorable face-on orientation, further facilitating the efficient charge transport. As a result, perovskite solar cells (PSCs) employing PE10 as dopant-free HTM afford an excellent efficiency of 22.3 % and the dramatically enhanced device longevity, qualifying it among the best PSCs based on dopant-free HTMs.

2.
Angew Chem Int Ed Engl ; 61(6): e202114341, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34806275

RESUMO

Adequate hole mobility is the prerequisite for dopant-free polymeric hole-transport materials (HTMs). Constraining the configurational variation of polymer chains to afford a rigid and planar backbone can reduce unfavorable reorganization energy and improve hole mobility. Herein, a noncovalent conformational locking via S-O secondary interaction is exploited in a phenanthrocarbazole (PC) based polymeric HTM, PC6, to fix the molecular geometry and significantly reduce reorganization energy. Systematic studies on structurally explicit repeats to targeted polymers reveals that the broad and planar backbone of PC remarkably enhances π-π stacking of adjacent polymers, facilitating intermolecular charge transfer greatly. The inserted "Lewis soft" oxygen atoms passivate the trap sites efficiently at the perovskite/HTM interface and further suppress interfacial recombination. Consequently, a PSC employing PC6 as a dopant-free HTM offers an excellent power conversion efficiency of 22.2 % and significantly improved longevity, rendering it as one of the best PSCs based on dopant-free HTMs.

3.
BMC Plant Biol ; 21(1): 103, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33602134

RESUMO

BACKGROUND: The overall genetic distribution and divergence of cloned genes among bread wheat varieties that have occurred during the breeding process over the past few decades in Ningxia Province, China, are poorly understood. Here, we report the genetic diversities of 44 important genes related to grain yield, quality, adaptation and resistance in 121 Ningxia and 86 introduced wheat cultivars and advanced lines. RESULTS: The population structure indicated characteristics of genetic components of Ningxia wheat, including landraces of particular genetic resources, introduced varieties with rich genetic diversities and modern cultivars in different periods. Analysis of allele frequencies showed that the dwarfing alleles Rht-B1b at Rht-B1 and Rht-D1b at Rht-D1, 1BL/1RS translocation, Hap-1 at GW2-6B and Hap-H at Sus2-2B are very frequently present in modern Ningxia cultivars and in introduced varieties from other regions but absent in landraces. This indicates that the introduced wheat germplasm with numerous beneficial genes is vital for broadening the genetic diversity of Ningxia wheat varieties. Large population differentiation between modern cultivars and landraces has occurred in adaptation genes. Founder parents carry excellent allele combinations of important genes, with a higher number of favorable alleles than modern cultivars. Gene flow analysis showed that six founder parents have greatly contributed to breeding improvement in Ningxia Province, particularly Zhou 8425B, for yield-related genes. CONCLUSIONS: Varieties introduced from other regions with rich genetic diversity and landraces with well-adapted genetic resources have been applied to improve modern cultivars. Founder parents, particularly Zhou 8425B, for yield-related genes have contributed greatly to wheat breeding improvement in Ningxia Province. These findings will greatly benefit bread wheat breeding in Ningxia Province as well as other areas with similar ecological environments.


Assuntos
Proteínas de Plantas/genética , Triticum/genética , Adaptação Fisiológica , Alelos , China , Frequência do Gene , Melhoramento Vegetal , Proteínas de Plantas/metabolismo , Triticum/crescimento & desenvolvimento , Triticum/fisiologia
4.
J Med Internet Res ; 23(6): e22395, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-34114959

RESUMO

BACKGROUND: Medical crowdfunding utilizes the internet to raise medical funds. Medical crowdfunding has developed rapidly worldwide; however, most medical crowdfunding projects fail to raise the targeted funds. Therefore, a very important research problem that has not received sufficient attention from the existing literature is identifying which factors affect the success of medical crowdfunding projects. OBJECTIVE: The aim of this study was to examine the effect of textual features of medical crowdfunding projects on their success rate using 4903 real projects from the Tencent Charity platform, a well-known medical crowdfunding platform in China. In particular, according to Aristotle's theory of persuasion, we divided the project text of medical crowdfunding into the project title and project details, which were analyzed from two perspectives (existence and extent) to explore their respective impacts. METHODS: We established a research framework to meet our research goals. The process was divided into five main parts. We first collected data from Tencent Charity using Python programs and cleaned the datasets. Second, we selected variables and built the research model based on previous studies and the theory of persuasion. Next, the selected variables were extracted from the project text. We then performed econometric analysis using multiple regression analysis. Finally, we evaluated the results of econometric analysis to extract knowledge. RESULTS: In the project title, the presence of the patient's disease (P=.04) and occupation (P=.01) had a positive impact on the success rate of fundraising, whereas the presence of age (P<.001), gender (P=.001), and negative emotions (P=.04) had a negative impact. In the project details, the presence of the patient's occupation (P=.01), monetary evidence (P=.02), and negative emotions (P=.04) played a positive role in the fundraising success rate, whereas the presence of age (P<.001) and positive emotions (P<.001) played a negative role. Moreover, in the project details, high-frequency monetary evidence (P=.02) and negative words (P=.02), as well as a short narrative length (P=.01) were conducive to succeeding in medical crowdfunding. Younger patients were more likely to obtain a higher success rate in medical crowdfunding. For patients whose occupations were national civil servant, professional skill worker, clerk, business and service worker, solider, child, student, and public-spirited person, the success rate of fundraising decreased sequentially. CONCLUSIONS: This study collected 4903 valid data from Tencent Charity, and identified which factors in the project text play an important role in the success rate of medical crowdfunding from the perspective of existence and extent. We found that in addition to the project details, the features of the project title also have an important impact on the success rate of fundraising. These findings provide important theoretical and managerial implications for medical crowdfunding.


Assuntos
Crowdsourcing , Obtenção de Fundos , Instituições de Caridade , Criança , Humanos , Conhecimento , Análise de Regressão
5.
J Am Chem Soc ; 142(41): 17681-17692, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32924464

RESUMO

Conjugated polymers are regarded as promising candidates for dopant-free hole-transport materials (HTMs) in efficient and stable perovskite solar cells (PSCs). Thus far, the vast majority of polymeric HTMs feature structurally complicated benzo[1,2-b:4,5-b']dithiophene (BDT) analogs and electron-withdrawing heterocycles, forming a strong donor-acceptor (D-A) structure. Herein, a new class of phenanthrocarbazole (PC)-based polymeric HTMs (PC1, PC2, and PC3) has been synthesized by inserting a PC unit into a polymeric thiophene or selenophene chain with the aim of enhancing the π-π stacking of adjacent polymer chains and also to efficiently interact with the perovskite surface through the broad and planar conjugated backbone of the PC. Suitable energy levels, excellent thermostability, and humidity resistivity together with remarkable photoelectric properties are obtained via meticulously tuning the conformation and elemental composition of the polymers. As a result, PSCs containing PC3 as dopant-free HTM show a stabilized power conversion efficiency (PCE) of 20.8% and significantly enhanced longevity, rendering one of the best types of PSCs based on dopant-free HTMs. Subsequent experimental and theoretical studies reveal that the planar conformation of the polymers contributes to an ordered and face-on stacking of the polymer chains. Furthermore, introduction of the "Lewis soft" selenium atom can passivate surface trap sites of perovskite films by Pb-Se interaction and facilitate the interfacial charge separation significantly. This work reveals the guiding principles for rational design of dopant-free polymeric HTMs and also inspires rational exploration of small molecular HTMs.

6.
J Cell Biochem ; 120(8): 13765-13774, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30989725

RESUMO

It has been proved that the expression of TLR4 is associated with a reduced risk of osteoporosis (OP). One single-nucleotide polymorphism located within the 3'-untranslated region (3'-UTR) of TLR4 may "generate" binding site of miR-34a and thereby associated with risk of OP. Bioinformatics analysis and luciferase reporter assay were used to specify the effect of polymorphisms on the interaction between miR-34a and TLR4 gene. Western blot analysis and real-time polymerase chain reaction were used to study the expressions of miR-34a, TLR4 in different groups or cells transfected with miR-34a mimics or inhibitor. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was used to estimate the effect of miR-34a on the apoptosis of osteoblast. TLR4 was identified as a target of miR-34a, with negative regulatory relationship predicted. The expression levels of miR-34a was comparable with each other between CC, CA, and AA groups, and the expression levels of TLR4 was evidently lower in CC compared with GG and GC groups. Also, TLR4 level in culture osteoblast (genotyped as CC) treated with miR-34a mimics was substantially downregulated compared with scramble control, while those cells (genotyped as CC) treated with miR-34a inhibitors showed increased expression of TLR4. Additionally, the apoptosis of osteoblast genotyped as CC was decreased following transfection with miR-34a mimics, while evidently promoted subsequent to transfect with miR-34a inhibitor. The regulatory association between rs1057317 polymorphism in TLR4 3'-UTR led to an inhibitory effect on the expression of TLR4 by miR-34a, which may explain the observed association between the polymorphism and the susceptibility to OP.


Assuntos
Regiões 3' não Traduzidas , Regulação da Expressão Gênica , Predisposição Genética para Doença , Osteoporose , Polimorfismo de Nucleotídeo Único , Receptor 4 Toll-Like , Idoso , Feminino , Humanos , Masculino , MicroRNAs/biossíntese , MicroRNAs/genética , Pessoa de Meia-Idade , Osteoporose/genética , Osteoporose/metabolismo , Osteoporose/patologia , Receptor 4 Toll-Like/biossíntese , Receptor 4 Toll-Like/genética
7.
J Am Chem Soc ; 141(50): 19700-19707, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31747277

RESUMO

Perovskite solar cells (PSCs) has skyrocketed in the past decade to an unprecedented level due to their outstanding photoelectric properties and facile processability. However, the utilization of expensive hole transport materials (HTMs) and the inevitable instability instigated by the deliquescent dopants represent major concerns hindering further commercialization. Here, a series of low-cost, conjugated polymers are designed and applied as dopant-free HTMs in PSCs, featuring tuned energy levels, good temperature and humidity resistivity, and excellent photoelectric properties. Further studies highlight the critical and multifaceted roles of the polymers with respect to facilitating charge separation, passivating the surface trap sites of perovskite materials, and guaranteeing long-term stability of the devices. A stabilized power conversion efficiency (PCE) of 20.3% and remarkably enhanced device longevity are achieved using the dopant-free polymer P3 with a low concentration of 5 mg/mL, qualifying the device as one of the best PSC systems constructed on the basis of dopant-free HTMs so far. In addition, the flexible PSCs based on P3 also exhibit a PCE of 16.2%. This work demonstrates a promising route toward commercially viable, stable, and efficient PSCs.

8.
Biochem Biophys Res Commun ; 495(1): 506-511, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29108992

RESUMO

Previous studies have demonstrated that microRNAs (miRNAs) play important roles in the pathogenesis of neuropathic pain. In the present study, we found that miR-32-5p was significantly upregulated in rats after spinal nerve ligation (SNL), specifically in the spinal microglia of rats with SNL. Functional assays showed that knockdown of miR-32-5p greatly suppressed mechanical allodynia and heat hyperalgesia, and decreased inflammatory cytokine (IL-1ß, TNF-α and IL-6) protein expression in rats after SNL. Similarly, miR-32-5p knockdown alleviated cytokine production in lipopolysaccharide (LPS)-treated spinal microglial cells, whereas its overexpression had the opposite effect. Mechanistic investigations revealed Dual-specificity phosphatase 5 (Dusp5) as a direct target of miR-32-5p, which is involved in the miR-32-5p-mediated effects on neuropathic pain and neuroinflammation. We demonstrated for the first time that miR-32-5p promotes neuroinflammation and neuropathic pain development through regulation of Dusp5. Our findings highlight a novel contribution of miR-32-5p to the process of neuropathic pain, and suggest possibilities for the development of novel therapeutic options for neuropathic pain.


Assuntos
Regulação para Baixo , Fosfatases de Especificidade Dupla/genética , MicroRNAs/genética , Neuralgia/genética , Animais , Células Cultivadas , Citocinas/análise , Inflamação/genética , Inflamação/patologia , Microglia/patologia , Neuralgia/patologia , Ratos Sprague-Dawley , Medula Espinal/metabolismo , Medula Espinal/patologia , Nervos Espinhais/metabolismo , Nervos Espinhais/patologia
9.
Phys Chem Chem Phys ; 15(36): 15146-52, 2013 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-23925069

RESUMO

In the present study, tetramethylammonium hydroquinone (HQ)/benzoquinone (BQ) were developed for use as a redox couple, with poly(3,4-ethylenedioxythiophene) (PEDOT) and multiwalled carbon nanotubes (MWNT) being proposed for use as counter electrode (CE) catalysts in dye-sensitized solar cells (DSSCs). Both metal-complex N719 and metal-free organic dye CM309 were employed to fabricate devices. For the devices sensitized by N719, when using PEDOT and MWNT CEs, power conversion efficiencies (PCE) of 5.2 and 4.9% were obtained, respectively, which were much higher than that of the device using the traditional Pt CE (4.7%) when HQ/BQ electrolyte was employed. However, with the HQ/BQ redox shuttle, the efficiency of the devices sensitized by N719 is much lower than that of the devices when the traditional I(-)/I3(-) based electrolyte and Pt CE were employed (7.9%). While for the CM309 sensitized solar cells, when the HQ/BQ redox shuttle was employed, PEDOT and MWNT performed much better than Pt, the DSSC using the PEDOT CE showed an efficiency of 6.2%, which was close to that of the DSSC using the traditional I(-)/I3(-) electrolyte and Pt CE (6.3%).


Assuntos
Benzoquinonas/química , Corantes/química , Fontes de Energia Elétrica , Hidroquinonas/química , Energia Solar , Eletrodos , Estrutura Molecular , Nanotubos de Carbono/química , Compostos Organometálicos/química , Oxirredução , Tamanho da Partícula , Propriedades de Superfície
10.
Nat Commun ; 14(1): 5486, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679329

RESUMO

Despite considerable research efforts on photoelectrochemical water splitting over the past decades, practical application faces challenges by the absence of efficient, stable, and scalable photoelectrodes. Herein, we report a metal-halide perovskite-based photoanode for photoelectrochemical water oxidation. With a planar structure using mesoporous carbon as a hole-conducting layer, the precious metal-free FAPbBr3 photovoltaic device achieves 9.2% solar-to-electrical power conversion efficiency and 1.4 V open-circuit voltage. The photovoltaic architecture successfully applies to build a monolithic photoanode with the FAPbBr3 absorber, carbon/graphite conductive protection layers, and NiFe catalyst layers for water oxidation. The photoanode delivers ultralow onset potential below 0 V versus the reversible hydrogen electrode and high applied bias photon-to-current efficiency of 8.5%. Stable operation exceeding 100 h under solar illumination by applying ultraviolet-filter protection. The photothermal investigation verifies the performance boost in perovskite photoanode by photothermal effect. This study is significant in guiding the development of photovoltaic material-based photoelectrodes for solar fuel applications.

11.
ACS Appl Mater Interfaces ; 15(9): 12485-12494, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36847773

RESUMO

A heterojunction is the key junction for charge extraction in many thin film solar cell technologies. However, the structure and band alignment of the heterojunction in the operating device are often difficult to predict from calculations and, due to the complexity and narrow thickness of the interface, are difficult to measure directly. In this study, we demonstrate a technique for direct measurement of the band alignment and interfacial electric field variations of a fully functional lead halide perovskite solar cell structure under operating conditions using hard X-ray photoelectron spectroscopy (HAXPES). We describe the design considerations required in both the solar cell devices and the measurement setup and show results for the perovskite, hole transport, and gold layers at the back contact of the solar cell. For the investigated design, the HAXPES measurements suggest that 70% of the photovoltage was generated at this back contact, distributed rather equally between the hole transport material/gold interface and the perovskite/hole transport material interface. In addition, we were also able to reconstruct the band alignment at the back contact at equilibrium in the dark and at open circuit under illumination.

12.
Angew Chem Int Ed Engl ; 51(39): 9896-9, 2012 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-22952034

RESUMO

A hybrid electrolyte involving tetramethylammonium (TMA) hydroquinone/benzoquinone redox couple is formulated. This electrolyte is more transparent than the traditional I(-)/I(3)(-) electrolyte and has negligible absorption in the visible region. Dye-sensitized solar cells using the hybrid electrolyte show higher light-to-electricity conversion efficiency. FTO=fluorine-doped tin oxide.


Assuntos
Benzoquinonas/química , Corantes/química , Fontes de Energia Elétrica , Hidroquinonas/química , Energia Solar , Eletricidade , Eletrólitos/química , Oxirredução , Compostos de Estanho/química
13.
J Environ Public Health ; 2022: 1231601, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36089976

RESUMO

Popularizing contemporary Chinese Marxism is urgently needed in order to support the ongoing development of socialism with Chinese characteristics as well as the inherent necessity of Marxism. This essay views the popularization of Marxism as a turning point in the new media environment. It examines the necessity and reality of this popularization in the new media era, considers the new development needs of the popularization of Marxism in propaganda, and further unearths the original construction concepts of the popularization of the Marxism propaganda network. In parallel, a Marxist learning platform is built using data mining technology. Studies reveal that this algorithm has a high clustering accuracy and a recall rate that is about 6% higher than DECluster's. Additionally, this algorithm takes less time to execute under the same scale transaction set. This demonstrates the superior performance of this algorithm. The user's learning record and learning interests can be formed into an intuitive law using the algorithm presented in this study, which can be used to analyze and calculate the user's learning content related to Marxism. This law can then be used to assist the user in creating a customized learning plan for Marxism.


Assuntos
Comunismo , Análise por Conglomerados
14.
Huan Jing Ke Xue ; 42(7): 3405-3412, 2021 Jul 08.
Artigo em Zh | MEDLINE | ID: mdl-34212667

RESUMO

In this study, a SBR reactor was selected to explore the effect of nitrogen and phosphorus removal by aerobic granular sludge under different initial anaerobic time using intermittent gradient aeration (decreasing dissolved oxygen concentration in each aeration section) and actual domestic wastewater with low C/N ratio as the influent matrix. The results showed that the initial anaerobic stage of intermittent gradient aeration increased from 50 min to 90 min, which increased the carbon source reserves in granular sludge. This improved delayed anaerobic condition led to the improvement of nitrogen and phosphorus removal efficiency of granular sludge. When delayed to 70 and 90 min, the removal efficiency of COD, TN, and TP reached 84.74%, 70.05%, and 89.7% and 86.65%, 78.81%, and 85.5%, respectively. However, after the first anaerobic phase time was increased to 110 min, the sludge loss was more severe owing to the disintegration of some cells, leading to a decrease in internal carbon source reserves by about 13.6%. Owing to this, the pollutant removal efficiency decreased. In the process of prolonging the first anaerobic phase time from 50 min to 90 min, the content of PS in LB-EPS changed minimally; when it was delayed to 110 min, the content of PS increased to about 7.18 mg·g-1, and the PN content increased to about 5.56 mg·g-1. The contents of PN and PS in TB-EPS were stable, which indicated that the effect of internal carbon storage on LB-EPS was greater than that of TB-EPS, and the decrease in sludge settling performance was closely related to the increase in PS content in LB-EPS. The proportion of DPAOs in granular sludge increased as the first anaerobic phase time increased, and the proportion of DPAOs reached 51.5% when the first anaerobic phase time was 70 min.


Assuntos
Fósforo , Esgotos , Anaerobiose , Reatores Biológicos , Nitrogênio , Eliminação de Resíduos Líquidos
15.
ACS Appl Mater Interfaces ; 12(30): 33751-33758, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32603585

RESUMO

Despite the ubiquity and importance of organic hole-transport materials in photovoltaic devices, their intrinsic low conductivity remains a drawback. Thus, chemical doping is an indispensable solution to this drawback and is essentially always required. The most widely used p-type dopant, FK209, is a cobalt coordination complex. By reducing Co(III) to Co(II), Spiro-OMeTAD becomes partially oxidized, and the film conductivity is initially increased. In order to further increase the conductivity, the hygroscopic co-dopant LiTFSI is typically needed. However, lithium salts are normally quite hygroscopic, and thus, water absorption has been suggested as a significant reason for perovskite degradation and therefore limited device stability. In this work, we report a LiTFSI-free doping process by applying organic salts in relatively high amounts. The film conductivity and morphology have been studied at different doping amounts. The resulting solar cell devices show comparable power conversion efficiencies to those based on conventional LiTFSI-doped Spiro-OMeTAD but show considerably better long-term device stability in an ambient atmosphere.

16.
ChemSusChem ; 13(22): 5901-5909, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-32896049

RESUMO

Tuning the local environment of nanomaterial-based catalysts has emerged as an effective approach to optimize their oxygen evolution reaction (OER) performance, yet the controlled electronic modulation around surface active sites remains a great challenge. Herein, directed electronic modulation of NiO nanoparticles was achieved by simple surface molecular modification with small organic molecules. By adjusting the electronic properties of modifying molecules, the local electronic structure was rationally tailored and a close electronic structure-activity relationship was discovered: the increasing electron-withdrawing modification readily decreased the electron density around surface Ni sites, accelerating the reaction kinetics and improving OER activity, and vice versa. Detailed investigation by operando Raman spectroelectrochemistry revealed that the electron-withdrawing modification facilitates the charge-transfer kinetics, stimulates the catalyst reconstruction, and promotes abundant high-valent γ-NiOOH reactive species generation. The NiO-C6 F5 catalyst, with the optimized electronic environment, exhibited superior performance towards water oxidation. This work provides a well-designed and effective approach for heterogeneous catalyst fabrication under the molecular level.

17.
Biomed Pharmacother ; 115: 108570, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31054509

RESUMO

Diabetic osteoporosis is a severe public health concern in the world. Puerarin (PU) is extensively attractive due to its superior bioactivities. In the study, we found that PU protected against streptozotocin (STZ)-induced osteoporotic changes in rats. PU treatment improved STZ-induced diabetes in rats, as evidenced by the reduced serum glucose and insulin levels. PU administration markedly attenuated bone loss and tartarate-resistant acid phosphatase (TRAP) activity in STZ-induced rats. Bone mineral density (BMD) was significantly decreased in diabetic rats, while being prevented by PU. STZ-induced impairments in microarchitecture of femoral tissues were markedly alleviated by PU treatment. In addition, bone-specific alkaline phosphatase (BALP), osteoprotegerin (OPG) and Runt-related transcription factor 2 (Runx2) levels in serum or tibia were improved by PU in STZ-injected rats; however, TRACP isoform 5b (TRACP-5b), carboxy-terminal collagen cross-links (ß-CTX) and receptor activator of nuclear factor-κB ligand (RANKL) levels were decreased. Further, PU treatment inhibited inflammation and apoptosis in STZ-treated rats. Additionally, STZ injection increased histone deacetylase (HDAC)-1 and -3 expressions in femoral heads of rats, which were relieved by PU treatment. Notably, both HDAC1 and HDAC3 could enhance osteoporosis in vitro, as proved by the decreased ALP and Runx2 levels and the increased TRAP expression. Inflammation and apoptosis were exacerbated by HDAC1/3 over-expression, which were markedly diminished by PU treatment. In contrast, suppressing HDAC1/3 significantly abrogated fructose (Fru)-elicited inflammation and apoptosis in cells. Collectively, our data illustrated that PU is a potential therapeutic option to prevent diabetic osteoporosis by inhibiting HDAC1/HDAC3 signaling.


Assuntos
Diabetes Mellitus Experimental/induzido quimicamente , Histona Desacetilase 1/metabolismo , Histona Desacetilases/metabolismo , Isoflavonas/farmacologia , Osteoporose/tratamento farmacológico , Animais , Anti-Inflamatórios/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Diabetes Mellitus Experimental/complicações , Frutose/toxicidade , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Histona Desacetilase 1/antagonistas & inibidores , Histona Desacetilase 1/genética , Histona Desacetilases/genética , Humanos , Inflamação/tratamento farmacológico , Osteoporose/etiologia , Ratos
18.
Curr Stem Cell Res Ther ; 13(3): 202-214, 2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-29285998

RESUMO

BACKGROUND: Spinal cord injuries (SCI) are prevalent, devastating for quality and expectancy of life, and cause heavy economic burdens. Stem cell therapies hold promise in complete structural and functional restoration of SCI. OBJECTIVE: This review focuses on the methods currently used to evaluate the stem cell therapies for SCI. RESULTS: Various kinds of stem cells involving embryonic stem cells (ESCs), bone marrow stromal cells (BMSCs), neural stem cells (NSCs) and induced pluripotent stem cells (iPSCs) are extensively used in regenerative research of SCI. For evaluation, the survival and integration of transplanted cells, spinal cord reconstruction and functional recovery all should be considered. Histological and histochemistrical, microscopic, and colorimetric assays, and real-time RT-PCR techniques are applied to determine the outcome. From the three main aspects-transplanted cells, spinal cord structure, and functional recovery-we summarize and discuss these methods with certain instances of applications in SCI models. Importantly, for the evaluations of function, neuronal transmitting, electrophysiological analysis and behavioral score are included. CONCLUSION: Wider conjunction of established technologies, as well as the further development of nondestructive methods might make a big difference in testing stem cell therapies.


Assuntos
Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/terapia , Medula Espinal/fisiologia , Transplante de Células-Tronco , Animais , Humanos , Regeneração Nervosa , Medicina Regenerativa , Medula Espinal/anatomia & histologia , Resultado do Tratamento
19.
ACS Omega ; 2(12): 9231-9240, 2017 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31457437

RESUMO

Triphenylamine-based metal complexes were designed and synthesized via coordination to Ni(II), Cu(II), and Zn(II) using their respective acetate salts as the starting materials. The resulting metal complexes exhibit more negative energy levels (vs vacuum) as compared to 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (Spiro-OMeTAD), high hole extraction efficiency, but low hole mobilities and conductivities. Application of dopants typically used for Spiro-OMeTAD was not successful, indicating a more complicated mechanism of partial oxidation besides the redox potential. However, utilization as hole-transport material was successful, giving a highest efficiency of 11.1% under AM 1.5G solar illumination.

20.
PLoS One ; 10(6): e0129459, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26125631

RESUMO

The rapid expansion of Internet brings us overwhelming online information, which is impossible for an individual to go through all of it. Therefore, recommender systems were created to help people dig through this abundance of information. In networks composed by users and objects, recommender algorithms based on diffusion have been proven to be one of the best performing methods. Previous works considered the diffusion process from user to object, and from object to user to be equivalent. We show in this work that it is not the case and we improve the quality of the recommendation by taking into account the asymmetrical nature of this process. We apply this idea to modify the state-of-the-art recommendation methods. The simulation results show that the new methods can outperform these existing methods in both recommendation accuracy and diversity. Finally, this modification is checked to be able to improve the recommendation in a realistic case.


Assuntos
Algoritmos , Serviços de Informação , Internet , Humanos , Teoria da Informação , Sistemas On-Line
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