Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 49
Filtrar
Mais filtros

Bases de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Biomed Chromatogr ; : e5924, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38922973

RESUMO

The co-administration of dapagliflozin (DPF) and sacubitril/valsartan (LCZ696) has emerged as a promising therapeutic approach for managing heart failure. Given that DPF and LCZ696 are substrates for P-glycoprotein, there is a plausible potential for drug-drug interactions when administered concomitantly. To investigate the pharmacokinetic changes when these drugs are co-administered, we have established and validated a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method capable of simultaneously detecting DPF, LBQ657 (the active metabolite of sacubitril) and valsartan in rat plasma. This method has demonstrated selectivity, sensitivity, and accuracy. Drug-drug interactions were examined by the LC-MS/MS method. The mechanisms were investigated using everted intestinal sac models and Caco-2 cells. The results showed that DPF significantly increased the area under the curve (AUC(0-t)) (3,563.3 ± 651.7 vs. 7,146.5 ± 1,714.9 h µg/L) of LBQ657 (the active metabolite of sacubitril) and the AUC(0-t) (24,022.4 ± 6,774.3 vs. 55,728.3 ± 32,446.3 h µg/L) of valsartan after oral co-administration. Dapagliflozin significantly increased the amount of LBQ657 and valsartan in intestinal sacs by 1- and 1.25-fold at 2.25 h. Caco-2 cell uptake studies confirmed that P-glycoprotein is the transporter involved in this interaction. This finding enhances the understanding of drug-drug interactions in the treatment of heart failure and provides a guidence for clinical therapy.

2.
Zhongguo Zhong Yao Za Zhi ; 49(2): 509-517, 2024 Jan.
Artigo em Zh | MEDLINE | ID: mdl-38403326

RESUMO

This study investigated the absorption profile of Wuwei Qingzhuo San in different intestinal segments and the absorption characteristics of its alkaloids(piperine, piperanine, piperlonguminine, and dihydropiperlonguminine). The everted gut sac model was established, and the chemical components of Wuwei Qingzhuo San in different intestinal segments were detected by UPLC-Q-TOF-MS. The content of piperine, piperanine, piperlonguminine, and dihydropiperlonguminine in intestinal absorption fluid was determined by UPLC-Q-TRAP-MS and the absorption parameters were calculated. The absorption characteristics in different intestinal segments at different time were analyzed. As a result, 27, 27, 8, and 6 absorbent components from Wuwei Qingzhuo San were detected in the intestinal cyst fluid of jejunum, ileum, duodenum, and colon by UPLC-Q-TOF-MS technology, respectively. It was also found that piperine, piperanine, piperlonguminine, and dihydropiperlonguminine from Wuwei Qingzhuo San showed linear absorption in various intestinal segments, with r values exceeding 0.9. In terms of absorption content, the components were ranked as piperine>piperanine>dihydropiperlonguminine>piperlonguminine in various intestinal segments, but the absorption rate and mechanism of each component varied. The results demonstrate that the absorption of the components of Wuwei Qingzhuo San in different intestinal segments is selective and is not a simple semi-permeable membrane permeation process.


Assuntos
Alcaloides , Piperidinas , Alcamidas Poli-Insaturadas , Benzodioxóis , Absorção Intestinal
3.
Int J Mol Sci ; 24(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37047097

RESUMO

Pathogen-associated molecular patterns (PAMPs) and danger-associated molecular patterns (DAMPs) induce NLRP3 inflammasome activation, and subsequent formation of active caspase-1 as well as the maturation of interleukin-1ß (IL-1ß) and gasdermin D (GSDMD), mediating the occurrence of pyroptosis and inflammation. Aberrant NLRP3 inflammasome activation causes a variety of diseases. Therefore, the NLRP3 inflammasome pathway is a target for prevention and treatment of relative diseases. Recent studies have suggested that NLRP3 inflammasome activity is closely associated with its post-translational modifications (PTMs). This review focuses on PTMs of the components of the NLRP3 inflammasome and the resultant effects on regulation of its activity to provide references for the exploration of the mechanisms by which the NLRP3 inflammasome is activated and controlled.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Caspase 1/metabolismo , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Processamento de Proteína Pós-Traducional , Piroptose/fisiologia , Humanos
4.
Molecules ; 28(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36838982

RESUMO

Bentysrepinine (Y101) is a novel phenylalanine dipeptide for the treatment of hepatitis B virus. Renal excretion played an important role in the elimination of Y101 and its metabolites, M8 and M9, in healthy Chinese subjects, although the molecular mechanisms of renal excretion and potential drug-drug interactions (DDIs) remain unclear. The present study aimed to determine the organic anion transporters (OATs) involved in the renal disposition of Y101 and to predict the potential DDI between Y101 and entecavir, the first-line agent against HBV and a substrate of OAT1/3. Pharmacokinetic studies and uptake assays using rat kidney slices, as well as hOAT1/3-HEK293 cells, were performed to evaluate potential DDI. The co-administration of probenecid (an inhibitor of OATs) significantly increased the plasma concentrations and area under the plasma concentration-time curves of M8 and M9 but not Y101, while reduced renal clearance and the cumulative urinary excretion of M8 were observed in rats. The time course of Y101 and M8 uptake via rat kidney slices was temperature-dependent. Moreover, the uptake of M8 was inhibited significantly by probenecid and benzylpenicillin, but not by p-aminohippurate or tetraethyl ammonium. M8 was found to be a substrate of hOAT3, but Y101 is not a substrate of either hOAT1 or hOAT3. Additionally, the entecavir inhibited the uptake of M8 in the hOAT3-transfected cells and rat kidney slices in vitro. Interestingly, no significant changes were observed in the pharmacokinetic parameters of Y101, M8 or entecavir, regardless of intravenous or oral co-administration of Y101 and entecavir in rats. In conclusion, M8 is a substrate of OAT3 in rats and humans. Furthermore, M8 also mediates the DDI between Y101 and entecavir in vitro, mediated by OAT3. We speculate that it would be safe to use Y101 with entecavir in clinical practice. Our results provide useful information with which to predict the DDIs between Y101 and other drugs that act as substrates of OAT3.


Assuntos
Proteína 1 Transportadora de Ânions Orgânicos , Transportadores de Ânions Orgânicos Sódio-Independentes , Humanos , Ratos , Animais , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , Proteína 1 Transportadora de Ânions Orgânicos/metabolismo , Probenecid/metabolismo , Probenecid/farmacologia , Ratos Wistar , Células HEK293 , Dipeptídeos/metabolismo , Interações Medicamentosas , Rim/metabolismo
5.
Zhongguo Zhong Yao Za Zhi ; 47(6): 1546-1557, 2022 Mar.
Artigo em Zh | MEDLINE | ID: mdl-35347952

RESUMO

Zhachong Shisanwei Pills, composed of 13 Chinese medicinal materials, are used for treating the diseases such as hemiplegia, pain of muscles and bones, rheumatism, and joint pain. The chemical composition and pharmacodynamics of Zhachong Shisanwei Pills have not been reported. Ultra-performance liquid chromatography/quadrupole-time-of-flight tandem mass spectrometry(UPLC-Q-TOF-MS/MS) was employed to quickly identify the chemical components of Zhachong Shisanwei Pills, which was performed with Shim-pack GIST C_(18) column(4.6 mm×150 mm, 5 µm). The gradient elution was conducted with methanol-0.05% acetic acid as the mobile phase. Electrospray ionization mass spectrometry(ESI-MS) was carried out in both positive and negative ion modes. The compounds were identidied based on accurate relative molecular weight, fragment ion species, and the MS data of reference substances and in literature. In conclusion, a total of 98 compounds were identified, including 19 organic acids, 36 flavonoids, 13 volatile oils, 8 tannins, 5 2-(2-phenylethyl)chromones, 5 amino acids, 3 sesquiterpenoids, 3 alkaloids, and 2 other compounds. This study characte-rized the chemical components of Zhachong Shisanwei Pills rapidly for the first time, laying a foundation for further research on the pharmacodynamic material basis and quality evaluation.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Medicamentos de Ervas Chinesas/química , Espectrometria de Massas por Ionização por Electrospray
6.
Psychooncology ; 30(9): 1492-1501, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33908116

RESUMO

OBJECTIVE: This study explored the mediating role of dyadic coping between self-efficacy, psychological distress and marital quality among young and middle-aged couples facing lymphoma. METHODS: A total of 243 couples in which the patients were lymphoma were recruited to complete Dyadic Coping Inventory, Locke-Wallace Marital Adjustment Scale for both. And Strategies Used by People to Promote Health, Fear of Progression Questionnaire-Short Form for patients; General Self-Efficacy Scale and Hospital Anxiety and Depression Scale for spouses. We used the statistical programs SPSS 20.0 and SPSS Amos 20.0 for data analysis. RESULTS: There were significant correlations between patient-spouse's dyadic coping and marriage quality scores. The patients' dyadic coping scores were significantly associated with their self-efficacy, fear of cancer recurrence scores, marriage quality, their spouse's self-efficacy, and marriage quality. The spouses' dyadic coping scores were significantly associated with their self-efficacy, anxiety, and marriage quality. The actor-partner interdependence mediation model analysis mediator effect of dyadic coping in the relationship between self-efficacy, psychological distress, and marriage quality had a good fit, with χ2 /df = 17.106, p = 0.194; root mean square error of approximation = 0.036; GFI = 0.992; CN = 243. CONCLUSIONS: For both patient and spouses, dyadic coping mediated impact of self-efficacy on marriage quality of themselves and their spouses, and individuals' dyadic coping mediated impact their psychological distress on marriage quality of themselves and spouses. The study highlighted the need for couple-based interventions and including strategies combined with individual and dyadic therapy for both partners.


Assuntos
Linfoma , Angústia Psicológica , Adaptação Psicológica , Promoção da Saúde , Humanos , Relações Interpessoais , Casamento , Pessoa de Meia-Idade , Autoeficácia
7.
Support Care Cancer ; 29(4): 1893-1902, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32803724

RESUMO

PURPOSE: The objectives are to explore the prevalence of DNR orders, the factors influencing them, and the association between DNR signing and health care utilization among advanced cancer patients. METHODS: This was a retrospective cohort study. Data from cancer decedents in three hospitals in China from January 2016 to December 2017 during their last hospitalization before death were obtained from the electronic medical records system. RESULTS: In total, 427 cancer patients were included; 59.0% had a DNR order. Patients who had solid tumors, lived in urban areas, had more than one comorbidity, and had more than five symptoms were more likely to have DNR orders. The cut-off of the timing of obtaining a DNR order was 3 days, as determined by the median number of days from the signing of a DNR order to patient death. Patients with early DNR orders (more than 3 days before death) were less likely to be transferred to the intensive care unit and undergo cardiopulmonary resuscitation, tracheal intubation, and ventilation, while they were more likely to be given morphine and psychological support compared with those with late (within 3 days before death) and no orders. CONCLUSIONS: Advanced cancer patients with solid tumors living in urban areas with more symptoms and comorbidities are relatively more likely to have DNR orders. Early DNR orders are associated with less aggressive procedures and more comfort measures. However, these orders are always signed late. Future studies are needed to better understand the timing of DNR orders.


Assuntos
Neoplasias/epidemiologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Ordens quanto à Conduta (Ética Médica)/psicologia , Idoso , China , Feminino , Humanos , Masculino , Estudos Retrospectivos , Assistência Terminal
8.
J Transl Med ; 18(1): 332, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32867783

RESUMO

BACKGROUND: Recently, it has been reported that miRNA is involved in pterygium, however the exact underlying mechanism in pterygium is unrevealed and require further investigation. METHODS: The differential expression of miRNA in pterygium was profiled using microarray and validated with quantitative real-time polymerase chain reaction (qRT-PCR). Human conjunctival epithelial cells (HCEs) were cultured and treated with transforming growth factor ß (TGF-ß) and epidermal growth factor (EGF) and transfected with miR-199a-3p/5p mimic and inhibitor. Markers of epithelial-mesenchymal transition (EMT) in HCEs were detected using western blot and immunohistochemistry. Cell migration ability was determined using wound healing and transwell assay, while apoptosis was determined by flow cytometry. The target genes of miR-199a were confirmed by the dual-luciferase reporter assay. RESULTS: TGF-ß and EGF could induced EMT in HCEs and increase miR-199a-3p/5p but suppress target genes, DUSP5 and MAP3K11. With the occurrence of EMT, cell migration ability was enhanced, and apoptosis was impeded. Promoting miR-199a-3p/5p expression could induce EMT in HCEs without TGF-ß and EGF, while suppressing miR-199a-3p/5p could inhibit EMT in TGF-ß and EGF induced HCEs. In a word, TGF-ß and EGF induced EMT could be regulated with miR-199a-3p/5p-DUSP5/MAP3K11 axes. The validated results in tissues showed that, compared with control conjunctival tissues, miR-199a-3p/5p were more overexpressed in pterygium, while DUSP5/MAP3K11 were lower expressed. In addition, bioinformatics analysis indicated the miR-199a-3p/5p-DUSP5/MAP3K11 was belong to MAPK signalling pathway. CONCLUSIONS: TGF-ß and EGF induce EMT of HCEs through miR-199a-3p/5p-DUSP5/MAP3K11 axes, which explains the pathogenesis of EMT in pterygium and may provide new targets for pterygium prevention and therapy.


Assuntos
MicroRNAs , Pterígio , Fosfatases de Especificidade Dupla , Fator de Crescimento Epidérmico/farmacologia , Transição Epitelial-Mesenquimal/genética , Humanos , MicroRNAs/genética , Pterígio/genética , Fator de Crescimento Transformador beta
9.
Mol Vis ; 26: 510-516, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32753832

RESUMO

Purpose: Signal transducer and activator of transcription 3 (STAT3) is a DNA-binding protein that regulates various biologic processes, including cell growth, apoptosis, and malignant transformation. Abnormal activation of STAT3 is associated with many diseases, and there is currently no relevant study on the pathogenesis of pterygium. The purpose of this study was to investigate the expression and clinical significance of STAT3, HIF-1α, and VEGF in pterygium at different stages. Methods: Immunohistochemistry was used to study the expression levels of STAT3, HIF-1α, and VEGF in 50 cases of pterygium and 20 cases of control conjunctival tissue. The expression intensity of the three proteins was evaluated with Image-Pro Plus 6.0 image analysis software. Results: In the pterygium group, the positive rates for STAT3, HIF-1α, and VEGF were 82.0%, 86.0%, and 84.0%, respectively, while those in the normal conjunctiva group were 40.0%, 25.0%, and 15.0%. The expression of STAT3, HIF-1α, and VEGF in pterygium was higher than that in control conjunctiva, and the expression in advanced pterygium was statistically significantly higher than that in stationary pterygium (p < 0.01). The expression levels of STAT3 and HIF-1α in pterygium were related to the length and depth of the corneal invasion of pterygium. The expression level of VEGF in pterygium was related to the length of pterygium, but not to the depth. In addition, there was a significant positive correlation between the expression of STAT3, HIF-1α, and VEGF (p < 0.01). Conclusions: For the first time, the expression levels of the STAT3, HIF-1α, and VEGF proteins were detected simultaneously in pterygium tissue. Compared with normal conjunctiva, STAT3, HIF-1α, and VEGF were highly expressed in pterygium, and the expression in advanced pterygium tissue was more significant than in the stationary pterygium tissue. It is suggested that STAT3 may directly or through HIF-1α promote VEGF expression and participate in the growth and angiogenesis of pterygium. Targeting STAT3 may provide a new direction for the treatment of pterygium.


Assuntos
Túnica Conjuntiva/anormalidades , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neovascularização Patológica/genética , Pterígio/genética , Fator de Transcrição STAT3/genética , Fator A de Crescimento do Endotélio Vascular/genética , Adulto , Idoso , Estudos de Casos e Controles , Túnica Conjuntiva/metabolismo , Túnica Conjuntiva/patologia , Córnea/metabolismo , Córnea/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Pterígio/metabolismo , Pterígio/patologia , Fator de Transcrição STAT3/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Xenobiotica ; 50(4): 468-478, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31329010

RESUMO

The objective of this study was to clarify the species differences of pharmacokinetics of Y101 (N-[N-benzoyl-O-(2-dimethylaminoethyl)-l-tyrosyl]-l-phenylalaninol hydrochloride), a derivative of herbal ingredient with anti-HBV hepatitis activity, in rats, dogs, monkeys and humans.The metabolic stability and metabolite identification studies using liver microsomes in vitro, plasma protein binding using a rapid equilibrium dialysis in vitro, pharmacokinetic studies in vivo were carried out to evaluate the interspecies differences. The toxicokinetic study in monkeys was also investigated.The metabolic profiles were similar in monkeys and humans, which were significant different from rats and dogs in vitro. In vitro plasma protein binding showed no major differences between species with medium to high protein binding rates. After single oral dose to rats, dogs, and monkeys, the absolute oral bioavailability of Y101 was 44.9%, 43.1%, and 19.2%, respectively. There was no accumulation for Y101 toxicokinetics in monkeys after oral administration for 90 d.The metabolic profiles indicated monkey was the very animal model for preclinical safety evaluation of Y101. Our results have demonstrated the favorable pharmacokinetics profile of Y101, which supports the clinical trials in humans.


Assuntos
Antivirais/metabolismo , Benzamidas/metabolismo , Dipeptídeos/metabolismo , Animais , Antivirais/farmacocinética , Benzamidas/farmacocinética , Dipeptídeos/farmacocinética , Cães , Hepatite B , Humanos , Microssomos Hepáticos/metabolismo , Ratos , Especificidade da Espécie
11.
Biomed Chromatogr ; 34(2): e4729, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31656040

RESUMO

FIM protein, which consists of 155 amino acids, was developed as a novel GLP-1 analog to reduce blood glucose, and pharmacodynamic results showed that it had a certain effect when used in treating Alzheimer's disease. The molecular weight of FIM is 16,304 Da. In theory, the concentration of FIM in biological samples should be determined by the ligand binding assay method or indirectly quantified using LC-MS/MS instrumentation. However, the above methods are complex and time-consuming. In this study, we successfully developed a simpler LC-MS/MS method for directly quantifying the intact FIM protein in monkey plasma for the first time. The chromatographic separation of FIM was achieved using an InertSustain Bio C18 column with a mobile phase of acetonitrile containing 0.1% formic acid (A)-water containing 0.1% formic acid (B) at a flow rate of 0.3 ml/min. Good linearity was observed in the concentration range of 5-500 ng/ml (r2 > 0.99). The intra- and inter-day precisions (expressed as relative standard deviation, RSD) of FIM were 2.30-12.8 and 7.30-13.2%, respectively. The intra- and inter-day accuracies (expressed as a relative error, RE) were -12.7-6.55 and - 10.1-0.892%, respectively. This method was successfully applied for a pharmacokinetic study of the FIM protein in four monkeys after subcutaneous administration.


Assuntos
Proteínas Sanguíneas/análise , Proteínas Sanguíneas/farmacocinética , Cromatografia Líquida/métodos , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Animais , Proteínas Sanguíneas/química , Limite de Detecção , Modelos Lineares , Macaca fascicularis , Reprodutibilidade dos Testes
12.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(11): 1107-1110, 2019 Nov 10.
Artigo em Zh | MEDLINE | ID: mdl-31703137

RESUMO

OBJECTIVE: To explore the genetic basis for a pedigree affected with Marfan syndrome (MFS). METHODS: Clinical data of the patients was collected. With genomic DNA extracted from peripheral blood samples, potential mutation was detected by targeted exome sequencing. Candidate variants were validated by Sanger sequencing and bioinformatic analysis. RESULTS: Targeted exome sequencing and Sanger sequencing revealed a missense c.649T to C(p.Trp217Arg) variant in the exon 7 of FBN1 gene, which was unreported previously. Bioinformatics analysis suggested that the variant can cause amino acid replacement and affect the structure and function of fibrillin-1. CONCLUSION: A novel missense variant of the FBN1 gene was identified, which probably underlies the autosomal dominant MFS in this pedigree.


Assuntos
Fibrilina-1/genética , Síndrome de Marfan/genética , Mutação de Sentido Incorreto , Análise Mutacional de DNA , Éxons , Fibrilinas , Humanos , Mutação , Linhagem
13.
Proc Natl Acad Sci U S A ; 112(7): 2181-6, 2015 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-25646446

RESUMO

Whether antibiotics induce the production of reactive oxygen species (ROS) that contribute to cell death is an important yet controversial topic. Here, we report that lethal attacks from bacterial and viral species also result in ROS production in target cells. Using soxS as an ROS reporter, we found soxS was highly induced in Escherichia coli exposed to various forms of attacks mediated by the type VI secretion system (T6SS), P1vir phage, and polymyxin B. Using a fluorescence ROS probe, we found enhanced ROS levels correlate with induced soxS in E. coli expressing a toxic T6SS antibacterial effector and in E. coli treated with P1vir phage or polymyxin B. We conclude that both contact-dependent and contact-independent interactions with aggressive competing bacterial species and viruses can induce production of ROS in E. coli target cells.


Assuntos
Bacteriófagos/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Humanos , Microscopia de Fluorescência , Reação em Cadeia da Polimerase , Vibrio cholerae/virologia
14.
Biomed Chromatogr ; 32(11): e4323, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29920712

RESUMO

Insulin is an effective therapeutic for diabetes, and the level of insulin in vivo is directly related to the health of diabetic patients. Traditionally, the concentrations of insulin in vivo are determined by the radioimmunoassay (RIA) method. In this study, we developed an LC-MS/MS method for the quantification of human insulin in dog plasma and directly compared the RIA and LC-MS/MS methods. Our LC-MS/MS method exhibited superior accuracy, efficiency and cost-effective for the pharmacokinetic (PK) assessment of human insulin. The LC-MS/MS method can quantitate human insulin and canine insulin simultaneously without cross-reactivity, making the analysis more efficient. The LLOQ of our LC-MS/MS method was 38.5 pg/mL, which was necessary to fully describe the PK profiles of endogenous and exogenous insulin in vivo. The direct comparison of PK data obtained from the two methods demonstrated that LC-MS/MS could be an alternative to the RIA method and should be widely used for the quantification of insulin drugs, especially in preclinical studies.


Assuntos
Cromatografia Líquida/métodos , Insulina Regular Humana/sangue , Insulina Regular Humana/farmacocinética , Radioimunoensaio/métodos , Espectrometria de Massas em Tandem/métodos , Animais , Cães , Feminino , Humanos , Limite de Detecção , Modelos Lineares , Masculino , Reprodutibilidade dos Testes
15.
Nano Lett ; 17(8): 5140-5147, 2017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28727458

RESUMO

We have demonstrated high-performance integrated perovskite/bulk-heterojunction (BHJ) solar cells due to the low carrier recombination velocity, high open circuit voltage (VOC), and increased light absorption ability in near-infrared (NIR) region of integrated devices. In particular, we find that the VOC of the integrated devices is dominated by (or pinned to) the perovskite cells, not the organic photovoltaic cells. A Quasi-Fermi Level Pinning Model was proposed to understand the working mechanism and the origin of the VOC of the integrated perovskite/BHJ solar cell, which following that of the perovskite solar cell and is much higher than that of the low bandgap polymer based organic BHJ solar cell. Evidence for the model was enhanced by examining the charge carrier behavior and photovoltaic behavior of the integrated devices under illumination of monochromatic light-emitting diodes at different characteristic wavelength. This finding shall pave an interesting possibility for integrated photovoltaic devices to harvest low energy photons in NIR region and further improve the current density without sacrificing VOC, thus providing new opportunities and significant implications for future industry applications of this kind of integrated solar cells.

16.
Nano Lett ; 17(1): 269-275, 2017 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-27936782

RESUMO

The ionic nature of perovskite photovoltaic materials makes it easy to form various chemical interactions with different functional groups. Here, we demonstrate that interfacial chemical interactions are a critical factor in determining the optoelectronic properties of perovskite solar cells. By depositing different self-assembled monolayers (SAMs), we introduce different functional groups onto the SnO2 surface to form various chemical interactions with the perovskite layer. It is observed that the perovskite solar cell device performance shows an opposite trend to that of the energy level alignment theory, which shows that chemical interactions are the predominant factor governing the interfacial optoelectronic properties. Further analysis verifies that proper interfacial interactions can significantly reduce trap state density and facilitate the interfacial charge transfer. Through use of the 4-pyridinecarboxylic acid SAM, the resulting perovskite solar cell exhibits striking improvements to the reach the highest efficiency of 18.8%, which constitutes an ∼10% enhancement compared to those without SAMs. Our work highlights the importance of chemical interactions at perovskite/electrode interfaces and paves the way for further optimizing performances of perovskite solar cells.

17.
J Am Chem Soc ; 138(48): 15710-15716, 2016 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-27934005

RESUMO

Morphology is critical component to achieve high device performance hybrid perovskite solar cells. Here, we develop a vapor induced intermediate phase (VIP) strategy to manipulate the morphology of perovskite films. By exposing the perovskite precursor films to different saturated solvent vapor atmospheres, e.g., dimethylformamide and dimethylsufoxide, dramatic film morphological evolution occurs, associated with the formation of different intermediate phases. We observe that the crystallization kinetics is significantly altered due to the formation of these intermediate phases, yielding highly crystalline perovskite films with less defect states and high carrier lifetimes. The perovskite solar cells with the reconstructed films exhibits the highest power conversion efficiency (PCE) up to 19.2% under 1 sun AM 1.5G irradiance, which is among the highest planar heterojunction perovskite solar cells. Also, the perovskite solar cells with VIP processing shows less hysteresis behavior and a stabilized power output over 18%. Our work opens up a new direction for morphology control through intermediate phase formation, and paves the way toward further enhancing the device performances of perovskite solar cells.

18.
Yao Xue Xue Bao ; 51(12): 1864-70, 2016 12.
Artigo em Zh | MEDLINE | ID: mdl-29908557

RESUMO

Bentysrepinine (Y101), a derivative of phenyalanine dipeptide, has a novel mechanism in the treatment of hepatitis B virus (HBV) infection with a good anti-HBV effect. In the present study, a fluorometric-based high throughput method using cytochrome P450 (CYP) screening kit was adopted to evaluate in vitro inhibition potential of Y101 on CYP isoenzymes by calculating remaining enzyme activities and inhibitory potential (IC(50) values) using the determined values of fluorescence intensity. The result showed that Y101 exhibited little activity in the inhibition of CYP1A2, CYP3A4, CYP2C9, CYP2C19 and CYP2D6 (IC(50) > 100 µmol·L(-1)). Y101 was used to treat human primary hepotocytes for 72 h, and the enzyme activities of CYP1A2, CYP2B6 and CYP3A4 were determined with a cocktail of probe substrates for the three CYP isoforms. The metabolites were simultaneously determined using a LC-MS/MS method. Y101 had no activity in the induction of CYP1A2, CYP2B6 and CYP3A4 on the basis of the following results: 1 The ratio of enzyme activities between test and control groups were all below than 1 (varied from 0.662 to 0.928); 2 The induction potential of Y101 were lower than forty percent compared with that of positive groups. The above results suggest that Y101 has little activity in the regulation of metabolic drug-drug interactions based on the CYP isoform changes following co-administration of drugs.


Assuntos
Antivirais/farmacologia , Benzamidas/farmacologia , Inibidores das Enzimas do Citocromo P-450/farmacologia , Sistema Enzimático do Citocromo P-450 , Dipeptídeos/farmacologia , Células Cultivadas , Cromatografia Líquida , Citocromo P-450 CYP1A2 , Citocromo P-450 CYP2C19 , Citocromo P-450 CYP3A , Interações Medicamentosas , Vírus da Hepatite B , Hepatócitos/efeitos dos fármacos , Humanos , Espectrometria de Massas em Tandem
19.
Zhonghua Yan Ke Za Zhi ; 51(1): 26-31, 2015 Jan.
Artigo em Zh | MEDLINE | ID: mdl-25877707

RESUMO

OBJECTIVE: To investigate the effect of corneal irregularity on on-eye rigid gas permeable (RGP) contact lenses and the corneal shape changed by RGP contact lenses. METHODS: Corneal topography was taken for 42 bare eyes of 22 subjects before and 1 month after wearing of the RGP contact lens. Off-eye and on-eye wavefront aberrations of the anterior surface of the RGP contact lens were also measured by corneal topography for the same 42 eyes. Zernike aberrations of the RGP contact lens were examined and compared to those of baseline anterior corneal surface. RESULTS: For bare eyes, C4, C5, C7 and C8 were significantly different from the baseline 30 minutes after the RGP contact lens was removed. For the on-eye RGP contact lens, three mean Zernike aberrations were significantly different from those off-eye. These were defocus C4 [OD: (1.003 ± 0.131) µm off-eye and (1.065 ± 0.160) µm on-eye, P = 0.015; OS: (1.003 ± 0.130) µm off-eye and 1.069 (0.851, 1.594) µm on-eye, P = 0.017], main axis astigmatism C5 [OD: (0.072 ± 0.083) µm off-eye and (-0.312 ± 0.232) µm on-eye, P < 0.001; OS: (0.066 ± 0.056) µm off-eye and (-0.349 ± 0.242) µm on-eye, P < 0.001], and spherical aberration C12 [OD: (0.264 ± 0.039) µm off-eye and (0.295 ± 0.048) µm on-eye, P < 0.001; OS: (0.266 ± 0.035) µm off-eye and 0.290 (0.215, 0.471) µm on-eye, P < 0.001]. All these three Zernike aberrations of on-eye RGP contact lenses were significantly correlated to those of the baseline corneas (OD: rc4=0.557, rc5=0.596, rc12=0.581, P < 0.01; OS: rc4=0.684, rc5=0.497, rc12=0.543, P < 0.01). CONCLUSIONS: The results suggest that the surface shape of on-eye RGP contact lenses is not rigid, and its change depends on irregularity of the anterior corneal surface, even if the cornea itself is changed by the RGP contact lens. It is better not to fit for RGP so flatter than the average curvature of the cornea.


Assuntos
Lentes de Contato Hidrofílicas , Córnea/fisiopatologia , Topografia da Córnea , Maleabilidade , Adulto , Astigmatismo/fisiopatologia , Córnea/patologia , Humanos , Procedimentos Ortoceratológicos
20.
Photodiagnosis Photodyn Ther ; 45: 103911, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38043761

RESUMO

BACKGROUND: Comparison of OPD-Scan III and Pentacam measurements of relevant parameters guiding the selection of multifocal intraocular lenses in cataract patients. METHODS: A retrospective study included 120 patients (120 eyes) with cataract. Their chord kappa, chord alpha, corneal spherical aberration, and pupil size were measured by OPD-Scan Ⅲ and Pentacam. Pairwise t-tests, Pearson tests, and Bland-Altman analyses were used, respectively, to assess the difference, correlation, and agreement between the devices. RESULTS: There was no significant difference in photopic chord kappa and corneal spherical aberration between the two instruments (P = 0.054, P = 0.065). Chord alpha and pupil size varied significantly between the two instruments (P < 0.001). OPD-Scan III results revealed a significant association between photopic chord kappa and mesopic chord kappa (r = 0.823, P < 0.001). There was a significant positive correlation between photopic and mesopic chord kappa measured by OPD-Scan Ⅲ and chord kappa measured by Pentacam (r = 0.840, r  = 0.757, P < 0.001). The chord alpha evaluated by the two tools had a moderate correlation (r = 0.442, P < 0.001) between them. Bland-Altman analysis showed that there was excellent agreement between the two instruments in measuring chord kappa and corneal spherical aberration, while the chord alpha and pupil size were not consistent. CONCLUSIONS: The chord kappa and corneal spherical aberration measured by OPD-Scan III and Pentacam were consistent in the preoperative decision making of multifocal intraocular lens implantation in cataract patients, both of which have clinical guiding significance. In addition, OPD-Scan III provides more comprehensive day and night chord kappa and pupil diameters, which improves clinical advice for patients with complicated ocular diseases and high demands for nocturnal vision.


Assuntos
Catarata , Fotoquimioterapia , Humanos , Acuidade Visual , Estudos Retrospectivos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes , Biometria
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA