Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Biochem Pharmacol ; : 116444, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39038551

RESUMO

Regenerating family protein 2 (Reg2) is a trophic factor which stimulates ß-cell replication and resists islet destruction. However, Reg2 also serves as an islet autoantigen, which makes it complicated to judge the effectiveness in treating diabetes. How Reg2 treatment behaves in non-obese diabetic (NOD) mice is to be investigated. NOD mice were treated with recombinant Reg2 protein, Complete Freund's adjuvant (CFA) + PBS and CFA+Reg2 vaccinations, CFA+PBS- and CFA+Reg2-immunized antisera, and single chain variable fragment (scFv)-Reg2 and mIgG2a-Reg2 antibodies. Glycemic level, bodyweight, serum Reg2 antibody titer, glucose tolerance, and insulin secretion were determined. Islet morphological characteristics, insulitis, cell apoptosis, islet cell components, and T cell infiltration were analyzed by histological examinations. The autoantigenicity of constructed Reg2C and Reg2X fragments was determined in healthy BALB/c mice, and the bioactivity in stimulating cell proliferation and survival was assessed in insulinoma MIN6 cells. Reg2 administration alleviated diabetes in NOD mice with improved glucose tolerance and insulin secretion but elevated serum Reg2 autoantibodies. Histomorphometry showed reduced inflammatory area, TUNEL signal and CD8 + T cell infiltration, and increased ß-cell proportion in support of the islet-protective effect of Reg2 treatment. CFA+PBS and CFA+Reg2 immunizations prevented diabetic onset and alleviated insulitis while injections of the antisera offered mild protections. Antibody treatments accelerated diabetic onset without increasing the overall incidence. Reg2C fragment depletes antigenicity, but reserves protective activity in streptozotocin (STZ)-treated MIN6 cells. In conclusion, Reg2 treatment alleviates type 1 diabetes (T1D) by preserving islet ß-cells, but induces Reg2 autoantibody production which poses a potential risk of accelerating diabetic progression.

3.
Biomacromolecules ; 25(1): 213-221, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38116982

RESUMO

Docetaxel (DOC) is commonly used in cancer treatment, especially for breast cancer. However, there are severe side effects in clinical application. In order to deliver docetaxel more effectively, a novel, active targeting acid-responsive polymer called cRGD-PAE-PEG-DSPE was developed. The polymer structure incorporated poly(ethylene glycol) (PEG) as the hydrophilic segment, 1,2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE) as the hydrophobic segment, and poly(ß-amino ester) (PAE) as the acid-responsive group, which was grafted onto the PEG. Furthermore, c(RGDyC) was grafted onto PAE to confer active targeting capability. Through self-assembly, docetaxel was encapsulated in RAED@DOC. Through in vitro experiments, it was confirmed that RAED@DOC had good serum stability and acid responsiveness, as well as enhanced uptake by MDA-MB-231 cells. Additionally, the antitumor efficiency in vivo and histopathological analysis showed that RAED@DOC exhibited higher antitumor activity and lower systemic toxicity in comparison to free docetaxel. These results suggested that RAED@DOC had considerable potential clinical use.


Assuntos
Antineoplásicos , Neoplasias da Mama , Nanopartículas , Humanos , Feminino , Docetaxel/farmacologia , Antineoplásicos/química , Polietilenoglicóis/química , Polímeros/química , Neoplasias da Mama/tratamento farmacológico , Nanopartículas/química , Linhagem Celular Tumoral
4.
Biomed Pharmacother ; 169: 115922, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38011786

RESUMO

Regenerating family protein 3 A (Reg3A) is highly expressed in a variety of organs and inflammatory tissues, and is closely related to tumorigenesis and cancer progression. However, clinical statistics show that high expression of Reg3A is associated with better prognosis in colorectal cancer (CRC) patients, suggesting a tumor-suppressive effect. The precise action and underlying mechanism of Reg3A in CRC remain controversial. The present study sought to investigate the relationship among Reg3A expression, CRC development, and immune cell alteration in patients using the TCGA, GEPIA, PrognoScan, TIMER and TISIDB databases. Reg3A-overexpressing LoVo cell line (LoVo-Reg3A), a representative of colon adenocarcinoma (COAD), was constructed and the action of Reg3A was assessed in a xenograft nude mouse model. Our bioinformatical analyses revealed that Reg3A upregulation is highly associated with CRC, along with increased frequency of immune cell infiltration. In the xenograft nude mice, Reg3A overexpression offered a tumor-suppressive effect by inhibiting cell proliferation and promoting apoptosis. The result of RNA-seq suggested a positive regulation of leukocytes and an upregulation of T cells in LoVo-Reg3A tumor tissue. CD4+ and CD8+ T cells in tumors, splenic Reg3A-reactive IFN-γ+/CD4+ T cells, and serum TNF-α, IFN-γ and IL-17 were significantly increased by Reg3A overexpression. In the ex vivo co-culture experiment, elevated cytotoxic effect, increased proportion of CD3ε+ T cells, and upregulated expressions of TNF-α, IFN-γ and IL-17 were detected in the PBMCs isolated from LoVo-Reg3A cell-xenografted nude mice. In conclusion, high expression of Reg3A could activate and recruit T cells in COAD leading to the cytotoxic tumor-suppressive effect.


Assuntos
Adenocarcinoma , Neoplasias do Colo , Animais , Humanos , Camundongos , Linfócitos T CD8-Positivos , Neoplasias do Colo/genética , Interleucina-17 , Camundongos Nus , Fator de Necrose Tumoral alfa
5.
Mol Neurobiol ; 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37996729

RESUMO

Inflammatory reaction plays a key role in the pathogenesis of hypoxic-ischemic encephalopathy (HIE) in neonates. Microglia are resident innate immune cells in the central nervous system and are profoundly involved in neuroinflammation. Studies have revealed that atorvastatin exerts a neuroprotective effect by regulating neuroinflammation in adult animal models of brain stroke and traumatic brain injury, but its role regarding damage to the developing brain remains unclear. This study aimed to clarify the effect and mechanism of atorvastatin on the regulation of microglia function in neonatal hypoxic-ischemic brain damage (HIBD). The oxygen glucose deprivation (OGD) of microglia and neonatal rat HIBD model was established. Atorvastatin, recombinant sclerostin protein (SOST), and XAV939 (degradation of ß-catenin) were administered to OGD microglia and HIBD rats. The pathological changes of brain tissue, cerebral infarction volume, learning and memory ability of rats, pro-inflammatory (CD16+/Iba1+) and anti-inflammatory (CD206+/Iba1+) microglia markers, inflammation-related indicators (Inos, Tnfα, Il6, Arg1, Tgfb, and Mrc1), and Wnt/ß-catenin signaling molecules were examined. Atorvastatin reduced OGD-induced pro-inflammatory microglia and pro-inflammatory factors, while increasing anti-inflammatory microglia and anti-inflammatory factors. In vivo, atorvastatin attenuated hypoxia-ischemia (HI)-induced neuroinflammation and brain damage. Mechanistically, atorvastatin decreased SOST expression and activated the Wnt/ß-catenin signaling pathway, and the administration of recombinant SOST protein or XAV939 inhibited Wnt/ß-catenin signaling and attenuated the anti-inflammatory effect of atorvastatin. Atorvastatin promotes the pro/anti-inflammatory phenotypic transformation of microglia via the Wnt/ß-catenin pathway in HI neonatal rats. Atorvastatin may be developed as a potent agent for the treatment of HIE in neonates.

6.
Foods ; 12(16)2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37628133

RESUMO

Many components (such as tea polyphenols, catechins, theaflavins, theasinensins, thearubigins, flavonoids, gallic acid, etc.) in black tea have antioxidant activities. However, it is not clear which components have a greater influence on the antioxidant activity of black tea. In this study, the antioxidant activity and contents of tea polyphenols, catechins, theaflavins, thearubigins, theabrownins, TSA, total flavonoids, amino acids, caffeine, and total soluble sugar were analyzed in 51 black teas. Principal component analysis (PCA), orthogonal partial least-squares discrimination analysis (OPLS-DA), and the correlation analysis method were used for data analysis. The results showed that catechins in tea polyphenols were the most important components that determine the antioxidant activity of black tea. Among them, epicatechin gallate (ECG), epi-gallocatechin gallate (EGCG), epicatechin (EC), and epi-gallocatechin (EGC) were significantly positively correlated with the antioxidant activity of black tea, and theabrownin was negatively correlated with the antioxidant activity of black tea. Furthermore, this study analyzed the correlation between the changes in catechin and its oxidized polymers with antioxidant activity during black tea fermentation; it verified that catechins were significantly positively correlated with the antioxidant activity of black tea, and theabrownin showed a negative correlation. And the antioxidant activity of catechins and their oxidation products in vitro and their correlation in black tea processing were used as validation. This study provides a comparison method for comparing the antioxidant activity of black tea.

7.
In Vivo ; 37(4): 1905-1913, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37369518

RESUMO

BACKGROUND/AIM: Renal cell carcinoma (RCC) of unknown primary origin is rarely identified and accounts for only 5% of cancers of unknown primary origin (CUP). The disease prognosis is typically poor because of no standard and effective therapy. Our review indicated that 23 cases have been reported and treated with conventional chemotherapy or tyrosine-kinase inhibitors alone; accordingly, most patients showed partial response or progression diseases with short survival time. CASE REPORT: Herein, we present two cases of metastatic RCC of unknown primary origin. One case was papillary type and the other was clear cell type. According to the recent clinical trials in patients with metastatic RCC, a combination of immunotherapy and tyrosine-kinase inhibitors exhibited better response than conventional therapy or tyrosine-kinase inhibitors alone. Both present cases accepted a combination treatment with immunotherapy and tyrosine-kinase inhibitor and showed stable diseases. The radiological progression-free time for the case with metastatic papillary RCC was 5 months, and that with clear cell RCC was 6 months until now. CONCLUSION: The combination of immunotherapy and tyrosine-kinase inhibitors is at least as effective as a tyrosine-kinase inhibitor alone, and superior to conventional chemotherapy for treating metastatic RCC of unknown primary origin.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Neoplasias Primárias Desconhecidas , Humanos , Carcinoma de Células Renais/diagnóstico , Carcinoma de Células Renais/tratamento farmacológico , Imunoterapia , Neoplasias Renais/tratamento farmacológico , Neoplasias Primárias Desconhecidas/diagnóstico , Neoplasias Primárias Desconhecidas/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Tirosina/metabolismo
8.
J Nanobiotechnology ; 21(1): 163, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37218019

RESUMO

Atopic dermatitis (AD) is a chronic and recurrent inflammation disease associated with immune dysfunction. The high level of reactive oxygen species (ROS) causes high oxidative stress and further results in the deterioration of AD. At the same time, the ROS produced by bacterial infection can further aggravate AD. Here, the prepared PVA-based hydrogel (Gel) has a high ROS scavenging ability, and the antibacterial agent Zn-MOF(ZIF-8) loaded into the hydrogel shows a lasting and effective antibacterial activity. Thus, a Zn-MOF hydrogel (Gel@ZIF-8) is prepared to regulate ROS-mediated inflammatory microenvironment. In vitro experiments show that Gel@ZIF-8 has good antibacterial effect and cell biocompatibility. In the AD-induced mouse model, Gel@ZIF-8 can significantly enhance the therapeutic effect, such as reduce the thickness of epidermis, the number of mast cells and IgE antibodies. The results indicate that the ROS-scavenging hydrogel could treat the AD by regulating the inflammatory microenvironment, providing a promising treatment for managing AD.


Assuntos
Dermatite Atópica , Animais , Camundongos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Dermatite Atópica/tratamento farmacológico , Hidrogéis/farmacologia , Hidrogéis/uso terapêutico , Espécies Reativas de Oxigênio , Zinco/farmacologia , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia
9.
Front Public Health ; 10: 938544, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36211645

RESUMO

Background and aim: Abdominal tuberculosis (TB) is a common type of extrapulmonary TB with an insidious onset and non-specific symptoms. Adenosine deaminase (ADA) levels increase rapidly in the early stages of abdominal TB. However, it remains unclear whether ADA serves as a diagnostic marker for abdominal TB. Methods: We performed a systematic literature search for relevant articles published in PubMed, Web of Science, Cochrane Library, and Embase up to April 2022. First, we used the Quality Assessment of Diagnostic Accuracy Studies tool-2 (QUADAS-2), to evaluate the quality of the included articles. Bivariate and hierarchical summary receiver operating characteristic (HSROC) models were then utilized to analyze pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and area under the receiver operating characteristic curve (AUROC). In addition, we explored a subgroup analysis for potential heterogeneity and publication bias among the included literature. Results: Twenty-four articles (3,044 participants, 3,044 samples) which met the eligibility criteria were included in this study. The pooled sensitivity and specificity of ADA for abdominal TB detection were 93% [95% confidence interval (CI): 0.89-0.95] and 95% (95% CI: 0.93-0.96), respectively. PLR and NLR were 18.6 (95% CI: 14.0-24.6) and 0.08 (95% CI: 0.05-0.12), respectively. DOR and AUROC were 236 (95% CI: 134-415) and 0.98 (95% CI: 0.96-0.99), respectively. Furthermore, no heterogeneity or publication bias was found. Conclusions: Our meta-analysis found ADA to be of excellent diagnostic value for abdominal TB and could be used as an auxiliary diagnostic tool. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier: CRD42022297931.


Assuntos
Adenosina Desaminase , Tuberculose , Humanos , Curva ROC , Sensibilidade e Especificidade , Tuberculose/diagnóstico
10.
Int J Mol Sci ; 23(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36142497

RESUMO

Progressive loss and dysfunction of islet ß-cells has not yet been solved in the treatment of diabetes. Regenerating protein (Reg) has been identified as a trophic factor which is demonstrated to be associated with pancreatic tissue regeneration. We previously produced recombinant Reg3α protein (rReg3α) and proved that it protects against acute pancreatitis in mice. Whether rReg3α protects islet ß-cells in diabetes has been elusive. In the present study, rReg3α stimulated MIN6 cell proliferation and resisted STZ-caused cell death. The protective effect of rReg3α was also found in mouse primary islets. In BALB/c mice, rReg3α administration largely alleviated STZ-induced diabetes by the preservation of ß-cell mass. The protective mechanism could be attributed to Akt/Bcl-2/-xL activation and GRP78 upregulation. Scattered insulin-expressing cells and clusters with small size, low insulin density, and exocrine distribution were observed and considered to be neogenic. In isolated acinar cells with wheat germ agglutinin (WGA) labeling, rReg3α treatment generated insulin-producing cells through Stat3/Ngn3 signaling, but these cells were not fully functional in response to glucose stimulation. Our results demonstrated that rReg3α resists STZ-induced ß-cell death and promotes ß-cell regeneration. rReg3α could serve as a potential drug for ß-cell maintenance in anti-diabetic treatment.


Assuntos
Células Secretoras de Insulina , Insulinas , Ilhotas Pancreáticas , Pancreatite , Doença Aguda , Animais , Apoptose , Glucose/metabolismo , Insulina/metabolismo , Células Secretoras de Insulina/metabolismo , Insulinas/metabolismo , Ilhotas Pancreáticas/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Pancreatite/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/farmacologia , Aglutininas do Germe de Trigo/farmacologia
11.
Biomaterials ; 288: 121723, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35963816

RESUMO

Granzyme B (GrB) is a pivotal killer factor in immunotherapy whose application is limited by hyposensitivity and unsatisfactory cellular uptake by tumor cells. In this study, it was proved that SerpinB9 (Sb9) downregulation can enhance the GrB susceptibility of tumor cells. Moreover, a nanocarrier fused with M1 macrophage exosomes (M1 Exo) and photothermal sensitive liposomes was constructed to efficiently transport GrB and siRNA of Sb9 to the cells. The nanocarrier is characterized by cascade tumor targeting acquired by photothermal effect-triggered increased expression of vascular cell adhesion molecule-1 (VCAM-1) in tumor tissue. Furthermore, the innate cytokines in M1 Exo are capable of regulating the tumor microenvironment by repolarizing M2 macrophages to the M1 type. Collectively, the multifunctional nanoplatform (S+G@ELP) enhances the lethality of GrB to tumor cells, activates a widespread immune response uniting with photothermal therapy (PTT), restrains the tumor progression and metastasis effectively, which is expected to provide new insights into GrB-based combinational tumor therapy.


Assuntos
Neoplasias , Serpinas , Biomimética , Linhagem Celular Tumoral , Granzimas/genética , Granzimas/metabolismo , Humanos , Imunoterapia , Neoplasias/terapia , Inibidores de Serina Proteinase , Serpinas/genética , Serpinas/metabolismo , Microambiente Tumoral
12.
Chin Med J (Engl) ; 135(12): 1474-1485, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35261352

RESUMO

BACKGROUND: Sepsis, a serious condition with high mortality, usually causes sepsis associated encephalopathy (SAE) that involves neuronal cell death. However, the cell death programs involved and their underlying mechanisms are not clear. This study aimed to explore the regulatory mechanisms of different cell death programs in SAE. METHODS: A neonatal rat model of SAE was established by cecal ligation and perforation. Survival rate and vital signs (mean arterial pressure and heart rate) were monitored, nerve reflexes were evaluated, and cortical pathological changes were observed by hematoxylin and eosin staining. The expression of pyroptosis, apoptosis, and necroptosis (PANoptosis)-related proteins, mitogen- activated protein kinase (MAPK), and its upstream regulator toll-like receptor 9 (TLR9) were detected. The expression of TLR9 in neurons was observed by immunofluorescence staining. The ultrastructure of neurons was observed by transmission electron microscope. RESULTS: First, PANoptosis was found in cortical nerve cells of the SAE rats. Meanwhile, the subunits of MAPKs, p38 MAPK, Jun N- terminal kinase, and extracellular signal-regulated kinase (ERK) were activated. After pharmacologically inhibiting each of the subunits, only p38 MAPK was found to be associated with PANoptosis. Furthermore, blocking the p38 MAPK signaling pathway activated necroptosis but inhibited apoptosis and pyroptosis. When necroptosis was pharmacologically inhibited, apoptosis and pyroptosis were reactivated. Finally, we found that the expression of TLR9, a regulator of MAPKs, was significantly increased in this model. After down-regulation of TLR9, p38 MAPK, and ERK signaling pathways were inhibited, which led to the inhibition of PANoptosis. Further analysis found that down-regulation of TLR9 improved the survival rate and reduced the pathological changes in SAE rats. CONCLUSIONS: Our study showed that the programs comprising PANoptosis are activated simultaneously in SAE rats. TLR9 activated PANoptosis through the p38 MAPK signaling pathway. TLR9 may work as a potential target for SAE treatment.


Assuntos
Encefalopatia Associada a Sepse , Proteínas Quinases p38 Ativadas por Mitógeno , Animais , Animais Recém-Nascidos , Apoptose , Amarelo de Eosina-(YS) , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Hematoxilina , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Mitógenos , Ratos , Transdução de Sinais , Receptor Toll-Like 9/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
13.
FASEB J ; 36(4): e22263, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35303316

RESUMO

Neuronal apoptosis is one of the main pathological processes of hypoxic-ischemic brain damage (HIBD) and is involved in the development of hypoxic-ischemic encephalopathy (HIE) in neonates. Atorvastatin has been found to have neuroprotective effects in some nervous system diseases, but its role in regulating the pathogenesis of neonatal HIBD remains elusive. Thus, this study aimed to explore the effects and related mechanisms of atorvastatin on the regulation of neuronal apoptosis after HIBD in newborn rats. The rat HIBD model and the neuronal oxygen glucose deprivation (OGD) model were established routinely. Atorvastatin, cAMP inhibitor (SQ22536), and BDNF inhibitor (ANA-12) were used to treat HIBD rats and OGD neurons. Cerebral infarction, learning and memory ability, cAMP/PKA/p-CREB/BDNF signaling molecules, and apoptosis-related indicators (TUNEL, cleaved caspase-3, and Bax/Bcl2) were then examined. In vivo, atorvastatin reduced cerebral infarction, improved learning and memory ability, decreased the number of TUNEL-positive neurons, inhibited the expression of cleaved caspase-3 and Bax/Bcl2, and activated the cAMP/PKA/p-CREB/BDNF pathway in the cerebral cortex after HIBD. In vitro, atorvastatin also decreased the apoptosis-related indicators and activated the cAMP/PKA/p-CREB/BDNF pathway in neurons after OGD. Furthermore, inhibition of cAMP or BDNF attenuated the effect of atorvastatin on the reduction of neuronal apoptosis, suggesting that atorvastatin inhibits HIBD-induced neuronal apoptosis and alleviates brain injury in neonatal rats mainly by activating the cAMP/PKA/p-CREB/BDNF pathway. In conclusion, atorvastatin may be developed as a potential drug for the treatment of neonatal HIE.


Assuntos
Fator Neurotrófico Derivado do Encéfalo , Hipóxia-Isquemia Encefálica , Animais , Animais Recém-Nascidos , Apoptose , Atorvastatina/farmacologia , Atorvastatina/uso terapêutico , Caspase 3 , Infarto Cerebral/tratamento farmacológico , Hipóxia , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Hipóxia-Isquemia Encefálica/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2 , Ratos , Ratos Sprague-Dawley , Proteína X Associada a bcl-2
16.
Small Methods ; 5(6): e2001090, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34927921

RESUMO

In perovskite solar cells (PSCs), a defective perovskite (PVK) surface and cliff-like energy offset at the interface always slow down the charge extraction; meanwhile, interface ion diffusion causes oxidation of the metal electrode, inducing device instability. Here, the in situ grown 2D-(CH3 NH2 )3 Sb2 I9 (MA3 Sb2 I9 ) on the back surface of MAPbI3 results in a more robust interface. MA3 Sb2 I9 changes the MAPbI3 surface to p-type and thus acts like a back surface field to drive charge extraction and suppress recombination, resulting in an obviously higher fill factor (FF) = 0.8 and power conversion efficiency (PCE) = 20.4% of SnO2 /MAPbI3 /MA3 Sb2 I9 /Spiro-OMeTAD (2,2',7,7'-Tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene) PSC than the pure MAPbI3 device. More importantly, strong chemical bonding of SbI prohibits ion diffusion, largely enhancing the thermal stability and longtime stability. Here, special 2D-MA3 Sb2 I9 constructs' robust band alignment and chemical environment at the interface are highlighted for efficient and stable PSCs.

17.
ACS Appl Mater Interfaces ; 13(1): 727-733, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33369383

RESUMO

Defective grain boundaries (GBs) and surface trap states are detrimental to the efficiency and stability of perovskite solar cells (PSCs). In this research, ionic liquid (IL) is used to control the defect states at the perovskite surface and GBs. The newly formed (EMIm)xMA1-xPb[(BF4)xI1-x]3 interlayer promotes secondary grain growth to diminish GBs; besides, EMIM+ and BF4- fill the vacancies of MA+ and I- and also passivate undercoordinated Pb2+ trap states. The newly formed interface largely reduces the nonradiative recombination, thus enhancing the solar-cell performance to 19.0% (AM 1.5, 1 sun) with higher photovoltage and fill factor than the control device. Due to the hydrophobicity of the (EMIm)xMA1-xPb[(BF4)xI1-x]3 interlayer, the unencapsulated device stability in 30 days is much better than the control device under relative humidity (RH) = 20%. This work highlights IL-induced secondary grain growth and a defect passivation method for efficient and stable PSCs.

18.
Exp Cell Res ; 396(1): 112278, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32918897

RESUMO

BACKGROUND: Regenerating protein 3a (Reg3a) is a trophic factor that functions as a stimulus in cell proliferation and neogenesis. Previous studies showed that Reg3a is ectopically upregulated in a majority of colorectal cancers (CRC) and detectable in the serum. METHODS: Single-chain variable fragment targeting Reg3a (scFv-Reg3a) was screened from a phage library. The bioactivity of recombinant Reg3a (rReg3a) and scFv-Reg3a were tested in LoVo and RKO cell lines using MTT, flow cytometry, wound healing and transwell analyses. Whether scFv-Reg3a inhibits tumor growth and enhances 5-fluorouracil (5-FU)-caused cell death were further examined in LoVo cell-transplanted nude BALB/c mice. RESULTS: A scFv-Reg3a from clone C2 was obtained and its binding affinity (KD) to rReg3a was determined to be 4.44 × 10-10. In cultured LoVo and RKO cells, rReg3a promoted but scFv-Reg3a inhibited cell proliferation, survival, migration and invasion. In LoVo cell-xenografted nude mice, administration of rReg3a accelerated tumor growth while scFv-Reg3a suppressed cell proliferation and reinforced 5-FU-induced cell death. CONCLUSION: The newly developed scFv-Reg3a is an anti-cancer agent which is potent to suppress CRC cell proliferation and survival. The use of scFv-Reg3a could enhance the effectiveness of 5-FU-based chemotherapy in the cancerous treatment.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Proteínas Associadas a Pancreatite/genética , Anticorpos de Cadeia Única/farmacologia , Animais , Antineoplásicos Imunológicos/química , Antineoplásicos Imunológicos/metabolismo , Apoptose/genética , Sítios de Ligação , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Clonagem Molecular , Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Fluoruracila/farmacologia , Expressão Gênica , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Modelos Moleculares , Proteínas Associadas a Pancreatite/antagonistas & inibidores , Proteínas Associadas a Pancreatite/química , Proteínas Associadas a Pancreatite/imunologia , Biblioteca de Peptídeos , Ligação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Anticorpos de Cadeia Única/biossíntese , Anticorpos de Cadeia Única/química , Carga Tumoral/efeitos dos fármacos
19.
Front Cell Neurosci ; 14: 211, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32754016

RESUMO

Ischemic brain injuries are common diseases with high morbidity, disability, and mortality rates, which have significant impacts on human health and life. Microglia are resident cells of the central nervous system (CNS). The inflammatory responses mediated by microglia play an important role in the occurrence and development of ischemic brain injuries. This article summarizes the activation, polarization, depletion, and repopulation of microglia after ischemic brain injuries, proposing new treatment strategies for such injuries through the modulation of microglial function.

20.
J Colloid Interface Sci ; 559: 29-38, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31606524

RESUMO

Organic-inorganic halide perovskites solar cells have garnered increasing attention in recent years due to the dramatic rise in power conversion efficiencies (PCEs). In perovskite solar cells (PSCs), selecting appropriate hole transport materials to insert between perovskite layer and electrodes can improve Schottky contact, facilitate the hole transport, therefore reduce charge recombination, and therefore improve cell performance. Doping of metal cation is an effective means to regulate energy level structure and change its conductivity. In this study, we novelly introduce the Pb2+ doped NiOx as the hole transport materials to decrease the energy loss between NiOx and the perovskite layer, which improves open-circuit voltage (Voc) of the PSCs. In order to improve the conductivity of the NiOx film, the Li+ co-doping is introduced. We introduce Pb and Li co-doping strategy to match the work function of doped NiOx with perovskite valence band energy level, and increase the conductivity of NiOx for high-efficiency inverted planar PSCs. The Pb and Li co-doped NiOx devices exhibit efficient hole extraction and enhanced conductivity, which improve the performance of inverted planar PSCs to 17.02% compared with 15.40% of the undoped device.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...