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1.
Sci Adv ; 10(16): eadl2063, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38640232

RESUMO

All-perovskite tandem solar cells (TSCs) have exhibited higher efficiencies than single-junction perovskite solar cells (PSCs) but still suffer from the unsatisfactory performance of low-bandgap (LBG) tin-lead (Sn-Pb) subcells. The inherent properties of PEDOT:PSS are crucial to high-performance Sn-Pb perovskite films and devices; however, the underlying mechanism has not been fully explored and revealed. Here, we report a facile oxalic acid treatment of PEDOT:PSS (OA-PEDOT:PSS) to precisely regulate its work function and surface morphology. OA-PEDOT:PSS shows a larger work function and an ordered reorientation and fiber-shaped film morphology with efficient hole transport pathways, leading to the formation of more ideal hole-selective contact with Sn-Pb perovskite for suppressing interfacial nonradiative recombination losses. Moreover, OA-PEDOT:PSS induces (100) preferred orientation growth of perovskite for higher-quality Sn-Pb films. Last, the OA-PEDOT:PSS-tailored LBG PSC yields an impressive efficiency of up to 22.56% (certified 21.88%), enabling 27.81% efficient all-perovskite TSC with enhanced operational stability.

2.
Org Lett ; 26(4): 834-838, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38240237

RESUMO

The first asymmetric synthesis of a scillascillin-type homoisoflavonoid was reported. Key reactions for the asymmetric synthesis of benzocyclobutene include catalytic reductive desymmetrization of malonic ester and an intramolecular C-H activation of the methyl group.

3.
J Orthop Surg Res ; 18(1): 737, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770926

RESUMO

BACKGROUND: Dorsal flap based on proper digital artery perforator has been commonly used in wound coverage of fingertip; yet a small diameter and short length poses a risk of pedicle kinking or occlusion. The present study aims to present our preliminary results of using a double-pivot perforator flap based on the end dorsal branch of proper digital artery to repair finger pulp defect. METHODS: We designed a double-pivot flap based on the end-dorsal perforator branch of proper digital artery, raised from the dorsal aspect of the middle phalanx, with inclusion of both the perforator and a section of the trunk of the artery. This modified procedure forms a pedicle with a larger diameter and length than traditional designs. Twelve patients (12 fingers) each with a soft-tissue defect of the fingertip were successfully treated and followed up in this retrospective study. RESULTS: All the flaps survived without showing any signs of necrosis; three cases presented with transient venous flow disorder, these self-resolving without requiring any additional treatment. At final follow-up (12-33 months, mean 20 months), mean static two-point discrimination on the flap was 7.0 mm (range, 6-9). CONCLUSION: The double-pivot proper digital artery flap serves as a reliable option in fingertip reconstruction offering added benefits of having greater rotation flexibility, a lower risk of vessel kinking or occlusion, and good recovery of cutaneous sensation.


Assuntos
Traumatismos dos Dedos , Retalho Perfurante , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Humanos , Estudos Retrospectivos , Traumatismos dos Dedos/cirurgia , Dedos/cirurgia , Dedos/irrigação sanguínea , Artérias/cirurgia , Lesões dos Tecidos Moles/cirurgia , Resultado do Tratamento
4.
Adv Mater ; 35(22): e2300352, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36906929

RESUMO

All-perovskite tandem solar cells (TSCs) hold great promise in terms of ultrahigh efficiency, low manufacturing cost, and flexibility, stepping forward to the next-generation photovoltaics. However, their further development is hampered by the relatively low performance of low-bandgap (LBG) tin (Sn)-lead (Pb) perovskite solar cells (PSCs). Improving the carrier management, including suppressing trap-assisted non-radiative recombination and promoting carrier transfer, is of great significance to enhance the performance of Sn-Pb PSCs. Herein, a carrier management strategy is reported for using cysteine hydrochloride (CysHCl) simultaneously as a bulky passivator and a surface anchoring agent for Sn-Pb perovskite. CysHCl processing effectively reduces trap density and suppresses non-radiative recombination, enabling the growth of high-quality Sn-Pb perovskite with greatly improved carrier diffusion length of >8 µm. Furthermore, the electron transfer at the perovskite/C60 interface is accelerated due to the formation of surface dipoles and favorable energy band bending. As a result, these advances enable the demonstration of champion efficiency of 22.15% for CysHCl-processed LBG Sn-Pb PSCs with remarkable enhancement in both open-circuit voltage and fill factor. When paired with a wide-bandgap (WBG) perovskite subcell, a certified 25.7%-efficient all-perovskite monolithic tandem device is further demonstrated.

6.
Beilstein J Org Chem ; 18: 1625-1628, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36530530

RESUMO

An approach to aberrarone, an antimalarial diterpenoid natural product with tetracyclic skeleton is reported. Key to the stereoselective preparation of the 6-5-5 tricyclic skeleton includes the mediation of Nagata reagent for constructing the C1 all-carbon quaternary centers and gold-catalyzed cyclopentenone synthesis through C-H insertion.

7.
Org Lett ; 23(15): 5684-5688, 2021 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-34251830

RESUMO

An intramolecular formal [3 + 2] cationic cycloaddition between benzylic carbocation and styrene was developed for the total synthesis of codonopiloneolignanin A. Further study shows benzocycloheptene as a good substrate for 1,3-dipolar cycloaddition, and a model study toward cephalocyclidine A skeleton was reported.


Assuntos
Lignanas/síntese química , Catálise , Reação de Cicloadição , Lignanas/química , Estrutura Molecular , Estereoisomerismo
8.
Chem Commun (Camb) ; 56(64): 9170-9173, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32657313

RESUMO

A novel La2Mg1.14Zr0.86O6:Bi3+ double perovskite phosphor with excitation-induced blue/green photoluminescence tuning is reported. By designing Bi3+→ Eu3+ energy transfer, single-composition white light with wide-scale adjustable corrected color temperatures (CCTs) is successfully achieved. This work initiates a new insight to explore phosphors with excitation-induced photoluminescence tuning and wide CCT control for future intelligent LED lighting.

9.
Adv Sci (Weinh) ; 7(8): 1903060, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32328419

RESUMO

Nowadays, red phosphor plays a key role in improving the lighting quality and color rendering index of phosphor-converted white light emitting diodes (w-LEDs). However, the development of thermally stable and highly efficient red phosphor is still a pivotal challenge. Herein, a new strategy to design antithermal-quenching red emission in Eu3+, Mn4+-codoped phosphors is proposed. The photoluminescence intensity of Mg3Y2(1- y )Ge3O12:yEu3+, Mn4+ (0 ≤ y ≤ 1) phosphors continuously enhances with rising temperature from 298 to 523 K based on Eu3+ → Mn4+ energy transfer. For Mg3Eu2Ge3O12:Mn4+ sample, the integrated intensity at 523 K remarkably reaches 120% of that at 298 K. Interestingly, through codoping Eu3+ and Mn4+ in Mg3Y2Ge3O12, the photoluminescence color is controllably tuned from orangish-red (610 nm) to deep-red (660 nm) light by changing Eu3+ concentration. The fabricated w-LEDs exhibit superior warm white light with low corrected color temperature (CCT = 4848 K) and high color rendering index (R a = 96.2), indicating the promising red component for w-LED applications. Based on the abnormal increase in antistokes peaks of Mn4+ with temperatures, Mg3Eu2Ge3O12:Mn4+ phosphor also presents a potential application in optical thermometry sensors. This work initiates a new insight to construct thermally stable and spectra-tunable red phosphors for various optical applications.

10.
Mol Med Rep ; 16(5): 6340-6345, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28849059

RESUMO

The present study aimed to evaluate the inhibitory effects of an irinotecan derivative, ZBH­1208, on brain tumors, and to explore the underlying molecular mechanisms. To determine the effects of ZBH­1208, a brain tumor mouse model was established by transplanting B22 cells. Subsequently, the visceral indices of immune organs and white blood cell counts were determined, and the effects of ZBH­1208 on the expression levels of cell cycle­related proteins were assessed by western blotting. The tumor inhibition rates of 20 and 40 mg/kg ZBH­1208 were 11.7 and 54.1%, respectively. Compared with the negative control group, ZBH­1208 barely affected visceral indices or white blood cell count. Furthermore, the expression levels of p53, p21, cyclin­dependent kinase 7 (CDK7), Wee1, phosphorylated (p)­cell division cycle 2 (CDC2) (Tyr15), p­CDC2 (Thr161) and cyclin B1 proteins were upregulated, whereas the expression levels of cyclin E were downregulated, and those of CDC2, CDK2 and CDC25C were barely altered. In conclusion, the present study demonstrated that ZBH­1208 suppressed the growth of B22 mouse brain tumor xenografts, but did not affect their visceral indices or white blood cell counts. It was suggested that ZBH­1208 exerted its effects by regulating the expression of p53, p21, Wee1, p­CDC2 (Tyr15) and cyclin E proteins.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Camptotecina/análogos & derivados , Regulação Neoplásica da Expressão Gênica , Imunidade Inata/efeitos dos fármacos , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Proteína Quinase CDC2/genética , Proteína Quinase CDC2/imunologia , Camptotecina/farmacologia , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/imunologia , Linhagem Celular Tumoral , Ciclina B1/genética , Ciclina B1/imunologia , Ciclina E/genética , Ciclina E/imunologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/imunologia , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/imunologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Vida Livre de Germes , Irinotecano , Masculino , Camundongos , Camundongos Endogâmicos ICR , Transplante de Neoplasias , Proteínas Nucleares/genética , Proteínas Nucleares/imunologia , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/imunologia , Transdução de Sinais , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/imunologia , Quinase Ativadora de Quinase Dependente de Ciclina
11.
Biomed Res Int ; 2015: 684945, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26457302

RESUMO

The new-emerging PRV variants plague the vaccinated pigs and caused huge economic loss to local pig industry in China since 2011. The current commercial PRV vaccines cannot provide complete protection as the new-emerging PRV variants are antigenically different from the classical viruses. It is urgent to develop more safe and effective PRV vaccines based on the current circulating field isolates. In this study, a gE gene-deleted PRV based on the PRV HN1201, a representative PRV variant, was generated and the efficacy was tested on 3-week-old pigs in the form of killed vaccine. After fatal PRV HN1201 challenge, all vaccinated pigs survived without showing any clinical symptoms, but all unvaccinated pigs exhibited pseudorabies-specific respiratory and neurological signs with 100% mortality rate within 6 days after infection. The vaccinated pigs developed high level of gB and neutralizing antibodies after vaccination which may correlate to the protection provided by vaccine. Therefore, this gE gene-deleted PRV could be a promising vaccine candidate for the control of currently epidemic pseudorabies in China.


Assuntos
Pseudorraiva/genética , Pseudorraiva/imunologia , Vacinas de Produtos Inativados/genética , Vacinas de Produtos Inativados/imunologia , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Linhagem Celular , Chlorocebus aethiops , Deleção de Genes , Suínos/imunologia , Suínos/virologia , Vacinação/métodos , Células Vero , Vacinas Virais/genética , Vacinas Virais/imunologia , Eliminação de Partículas Virais/imunologia
12.
Mol Med Rep ; 12(3): 4592-4597, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26082082

RESUMO

Osthole (7-methoxy-8-isoamyl alkenyl coumarin) has been reported to exhibit marked anticancer effects on several types of cancer. The expression levels of matrix metalloproteinase-9 (MMP-9) are closely associated with the pathogenesis of glioma. Furthermore, it is reported that the upregulation of microRNA­16 (miR­16) by the MMP­9 signaling pathway can restrain the proliferation of cancer cells. To examine whether osthole increases the anticancer effect on human glioma cells in the present study, the common glioma cell line, U87, was treated with osthole at concentrations of 0, 50, 100 and 200 µΜ. The effects of osthole on cell viability were determined using a 3­(4,5­dimethylthiazol­2­thiazolyl)­2,5­diphenyl­tetrazolium bromide assay. The rate of cellular apoptosis was analyzed by measuring the activity of caspase­3 and using flow cytometry. The expression of MMP­9 was determined using gelatin zymography assays and the expression of miR­16 was determined using reverse transcription­quantitative polymerase chain reaction. The results demonstrated that osthole significantly suppressed the proliferation and accelerated the apoptosis of the U87 cells. Furthermore, increased expression levels of miR­16 and reduced protein expression levels of MMP­9 were found in the U87 cells. In addition, miR­16 was found to regulate the expression of MMP­9 in the U87 cells through transfection of miR­16 precursor and anti­miR­16 into the U87 cells. In conclusion, these observations indicated that osthole suppressed the proliferation and accelerated the apoptosis of human glioma cells through upregulation of the expression of miR­16 and downregulation of the expression of MMP-9.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apiaceae/química , Cumarínicos/farmacologia , Regulação Neoplásica da Expressão Gênica , Metaloproteinase 9 da Matriz/genética , MicroRNAs/genética , Neuroglia/efeitos dos fármacos , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cumarínicos/isolamento & purificação , Relação Dose-Resposta a Droga , Humanos , Metaloproteinase 9 da Matriz/metabolismo , MicroRNAs/agonistas , MicroRNAs/metabolismo , Neuroglia/metabolismo , Neuroglia/patologia , Extratos Vegetais/química , Transdução de Sinais
13.
Int J Clin Exp Pathol ; 8(4): 4269-76, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26097624

RESUMO

Phenethyl isothiocyanate (PEITC) is one of the best studied members of isothiocyanates (ITC), a variety of edible cruciferous vegetables including broccoli, watercress, and cabbage, and have generated particular interest because of its remarkable chemopreventive activity. Many literature reports proved that phenethyl isothiocyanate exhibited significant anti-cancer chemopreventive effects including lung, glioma and leukemia cancer. In this study, we explored the inhibitory effects as well as mechanisms of PEITC on human glioma LN229 cells. Results demonstrated that PEITC possesses the potential ability to inhibit proliferation, induce apoptosis and arrest cell cycling against LN229 human glioma cells. Moreover, investigated results showed that PEITC inhibited the expression of superoxide dismutase (SOD) and glutathione (GSH), and caused oxidative stress to tumor cells. Collective results suggested us to believe that PEITC can inhibit the growth of LN229 cells and its mechanism can be related to the fact that PEITC can cause oxidative stress to tumor cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Glioma/tratamento farmacológico , Isotiocianatos/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Glioma/metabolismo , Glioma/patologia , Glutationa/metabolismo , Humanos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
14.
PM R ; 4(2): 123-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22192459

RESUMO

OBJECTIVE: To apply and examine the performance of 2 acute stroke outcome prediction models, the Six Simple Variable Model (SSV model) and the One-Year Mortality Model (OYM model), in patients in China who had either a cerebral infarction or a cerebral hemorrhage. DESIGN: An observational study that used both retrospective and prospective study methods. SETTING: A regional acute care facility in China. PARTICIPANTS: Two hundred and forty-eight consecutive patients who had an acute stroke who were admitted to the hospital between October 2007 and March 2009. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Survival and daily activity independence 6 months after a stroke and 1-year mortality. RESULTS: The study sample had a mean age of 68.6 years (standard deviation, 11.1); 52.8% of the subjects were men, 66.5% had a cerebral infarction, and 33.5% had a cerebral hemorrhage. In the cohort, 107 patients (43.1%) achieved daily activity independence at 6-month follow-up, and 52 patients (21.0%) had died within 1 year. The area under the receiver operating characteristic curve (ROC) was 0.966 (0.935-0.998) for patients who had a cerebral infarction and 0.859 (0.766-0.952) for patients who had a cerebral hemorrhage in the prediction of 6-month survival and daily activity independence with use of the SSV model. The area under the ROC curve was 0.894 (0.846-0.965) for patients who had a cerebral infarction and 0.937 (0.904-0.988) for patients who had a cerebral hemorrhage in the prediction of 1-year mortality when the OYM model was used. CONCLUSIONS: Both the SSV and OYM prognostic models can be used for function and mortality outcome prediction for patients in China who have had a stroke. Variation existed in the precision of prediction between patients who had a cerebral infarction and those who had a cerebral hemorrhage. Other potential factors influencing functional recovery and mortality after stroke must be considered in outcome prediction.


Assuntos
Acidente Vascular Cerebral/mortalidade , Atividades Cotidianas , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Curva ROC , Estudos Retrospectivos , Reabilitação do Acidente Vascular Cerebral , Taxa de Sobrevida
15.
J Chem Neuroanat ; 36(3-4): 138-43, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18692128

RESUMO

Neurotrophins (NTs) appear to be crucial for the survival and potential regeneration of injured neurons. However, their temporal changes and remote regulations following spinal cord injury (SCI) have been only partially determined, especially in primates. In this study, ELISA was performed on the extracts of injured spinal cord and the associated precentral gyrus contralateral to the site of spinal cord hemisection to investigate the temporal changes in the levels of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and neurotrophin-4 (NT-4) in adult rhesus monkeys subjected to T8 spinal hemisection. Animals were allowed to survive 3, 7, 14, 30 and 90 days post-operation (dpo). In the spinal cord, the levels of NGF, BDNF and NT-3 sharply decreased between 3 and 7dpo. Thereafter, the levels of NGF and BDNF were transiently elevated while NT-3 level continuously increased and recovered to normal level at 30dpo. In the contralateral precentral gyrus (cPG), only the NT-3 level was altered and in fact elevated above the normal value. No obvious changes were observed in NT-4 level in any of the regions studied. Taken together, the present findings indicated that intrinsic NGF, BDNF and NT-3 may play a local role in the responses to the SCI in primates. Especially, the increase of NT-3 level occurred continuously in both the cPG and the spinal cord pointed to a possible transportation of NT-3 to the cord following SCI.


Assuntos
Fatores de Crescimento Neural/metabolismo , Medula Espinal/metabolismo , Actinas/metabolismo , Animais , Western Blotting , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Ensaio de Imunoadsorção Enzimática , Imuno-Histoquímica , Macaca mulatta , Masculino , Neurotensina/metabolismo
16.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 36(3): 322-4, 2005 May.
Artigo em Chinês | MEDLINE | ID: mdl-15931857

RESUMO

OBJECTIVE: To investigate the distribution of Fas and FasL in the CNS of adult rhesus. METHODS: Frozen sections were incubated in polyclonal anti-Fas and anti-FasL antibody by the immunohistochemical SP method. RESULTS: The Fas and FasL immunopositive neurons were observed in many areas. Fas immunoreactivity could be seen in the cytoplasm and processes of Purkinje cells and in the brain stem nuclei, including vestibular nucleus, dorsal nucleus of vagus and spinal nucleus of trigeminal nerve. FasL immunopositive neurons were observed in cerebral cortex, especially in pyramidal neurons of lamina I and V, cerebellar nuclei, diencephalon, and brain stem nuclei involving pontine nucleus, vestibular nucleus, cochlear nucleus, spinal nucleus of trigeminal nerve, hypoglossal nucleus, nucleus ambiguous and reticular formation. Fas and FasL immunoreactivity mainly distributed in motor neurons of spinal ventral horn and neural fibers and glia cells in white matter. They all took on brown staining in the cytoplasm and process. CONCLUSION: The distribution profiles of Fas and FasL in various areas of CNS indicate that they may fill some roles in the immune and physical function of the aforesaid anatomic


Assuntos
Química Encefálica , Glicoproteínas de Membrana/metabolismo , Fatores de Necrose Tumoral/metabolismo , Receptor fas/metabolismo , Animais , Tronco Encefálico/química , Córtex Cerebral/química , Proteína Ligante Fas , Macaca mulatta , Masculino , Medula Espinal/química , Distribuição Tecidual , Núcleos Vestibulares/química
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