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1.
Value Health ; 27(2): 153-163, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38042333

RESUMO

OBJECTIVES: To assess the cost-effectiveness of trastuzumab deruxtecan compared with trastuzumab emtansine as second-line therapy for patients with human epidermal growth factor receptor 2 positive metastatic breast cancer from a US healthcare sector perspective. METHODS: A 3-state partitioned survival model was developed to estimate the cost-effectiveness of trastuzumab deruxtecan compared with trastuzumab emtansine. For both treatments, modeled patients were administered treatment intravenously every 3 weeks indefinitely or until disease progression. Transition parameters were principally derived from the updated DESTINY-Breast03 phase III randomized clinical trial. Costs include drug costs extracted from Centers for Medicare and Medicaid Services average sales price and administrative, adverse event, and third-line therapy costs derived from published literature, measured in 2022 US dollars. Health utilities for health states and disutilities for adverse events were sourced from published literature. Effects were measured in quality-adjusted life years (QALYs). We conducted both probabilistic sensitivity analysis and comprehensive scenario analysis to test model assumptions and robustness, while utilizing a lifetime horizon. RESULTS: In our base-case analysis, total costs for trastuzumab deruxtecan were $1 266 945, compared with $820 082 for trastuzumab emtansine. Total QALYs for trastuzumab deruxtecan were 5.09, compared with 3.15 for trastuzumab emtansine. The base-case incremental cost-effectiveness ratio was $230 285/QALY. Probabilistic sensitivity analysis indicated that trastuzumab deruxtecan had an 11.1% probability of being cost-effective at a $100 000 per QALY willingness-to-pay threshold. CONCLUSIONS: Despite the higher efficacy of trastuzumab deruxtecan in patients with human epidermal growth factor receptor 2 positive metastatic breast cancer, our findings raise concern regarding its value at current prices.


Assuntos
Neoplasias da Mama , Camptotecina/análogos & derivados , Imunoconjugados , Idoso , Humanos , Estados Unidos , Feminino , Ado-Trastuzumab Emtansina/uso terapêutico , Análise de Custo-Efetividade , Análise Custo-Benefício , Medicare , Trastuzumab , Receptor ErbB-2/metabolismo , Anos de Vida Ajustados por Qualidade de Vida , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
2.
Postepy Dermatol Alergol ; 41(1): 66-71, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38533362

RESUMO

Introduction: Melasma is an acquired hypermelanosis and occurs in areas exposed to sunlight. Aim: To investigate the effectiveness of Danggui Shaoyao powder (DSP) as a complementary drug in the treatment of melasma. Material and methods: A total of 40 melasma patients over the age of 18 who met the inclusion criteria entered the study randomly in two DSP + Hydroquinone (DSP + H) and Hydroquinone (H) groups. Results: At the beginning of the study, the average MASI score of the two groups of patients had no statistical difference (DSP + H: 15.79 ±1.01 vs. H: 15.37 ±1.17, p = 0.23). But from the eighth week of treatment, the MASI score of the patients decreased significantly and in the DSP + H group it decreased statistically significantly compared to the H group (DSP + H: 5.83 ±0.97 vs. H: 8.29 ±2.23, p < 0.001 for the eighth week and DSP + H: 3.60 ±0.58 vs. H: 5.52 ±1.73, p < 0.001 for the twelfth week of the treatment). It means after 12 weeks of treatment, the average MASI score of patients in the DSP + H group decreased by 77.26 ±2.70%, but in the grroup H, it decreased by 64.31 ±9.68% (p < 0.001). Dynamic PGA showed that excellent treatment occurred in 65% of the + H group H, but only 20% of the H group (p = 0.01). Conclusions: Oral DSP for 12 weeks along with hydroquinone cream can significantly reduce the MASI score of melasma patients and increase the patients' recovery and satisfaction.

3.
Circulation ; 146(25): 1950-1967, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36420731

RESUMO

BACKGROUND: Cardiac regeneration after injury is limited by the low proliferative capacity of adult mammalian cardiomyocytes (CMs). However, certain animals readily regenerate lost myocardium through a process involving dedifferentiation, which unlocks their proliferative capacities. METHODS: We bred mice with inducible, CM-specific expression of the Yamanaka factors, enabling adult CM reprogramming and dedifferentiation in vivo. RESULTS: Two days after induction, adult CMs presented a dedifferentiated phenotype and increased proliferation in vivo. Microarray analysis revealed that upregulation of ketogenesis was central to this process. Adeno-associated virus-driven HMGCS2 overexpression induced ketogenesis in adult CMs and recapitulated CM dedifferentiation and proliferation observed during partial reprogramming. This same phenomenon was found to occur after myocardial infarction, specifically in the border zone tissue, and HMGCS2 knockout mice showed impaired cardiac function and response to injury. Finally, we showed that exogenous HMGCS2 rescues cardiac function after ischemic injury. CONCLUSIONS: Our data demonstrate the importance of HMGCS2-induced ketogenesis as a means to regulate metabolic response to CM injury, thus allowing cell dedifferentiation and proliferation as a regenerative response.


Assuntos
Infarto do Miocárdio , Miócitos Cardíacos , Camundongos , Animais , Miócitos Cardíacos/metabolismo , Coração , Miocárdio/metabolismo , Camundongos Knockout , Regeneração/genética , Proliferação de Células , Mamíferos
4.
Phys Chem Chem Phys ; 25(5): 3780-3788, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36644933

RESUMO

Hydrogen transfer (HT) is of crucial importance in biochemistry and atmospheric chemistry. Here, HT processes involved in the dissociation reaction of dimethyl disulfide radical cations (DMDS˙+, CH3SSCH3˙+) are investigated using quantum chemical calculations. Four HTs from the C to S atom and one HT from the S to S atom are observed and the most probable paths are proposed in the dissociation channel from DMDS˙+ to CHnS+ (n = 2-4). The mechanisms of all these five HTs are described as hydrogen atom transfer (HAT) and four of them are accompanied by electron transfer (ET). Considering the catalytic effect of water molecules existing in organisms and the atmosphere, five HT processes in the dissociation of the [DMDS + H2O]˙+ complex are further explored, which show lower free energy barriers. With the participation of water molecules acting as a base, two HTs from the C to the S atom, which have the largest decrease in energy barriers, are characterized as concerted proton-coupled electron transfer (cPCET). These results can be extended to understand the mechanism of the HT process during the dissociation of disulfide and help provide a strategy to design a rare cPCET mechanism for the activation of the C-H bond.

5.
Curr Cardiol Rep ; 25(5): 325-331, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37074564

RESUMO

PURPOSE OF REVIEW: Heart failure leads to high mortality. The failing myocardium cannot often be rescued as heart regeneration is mostly compromised by disease progress. Stem cell therapy is a strategy under development to replace the impaired myocardium for recovery after heart injury. RECENT FINDINGS: Many studies have provided evidence of the beneficial effects of pluripotent stem cell-derived cardiomyocyte (CM) implantation into diseased rodent hearts, but there are still many challenges and limitations to replicating the same effects in large animal models for preclinical validation. In this review, we summarize progress in the use of pluripotent stem cell-derived CMs in large animal models based on three key parameters: species selection, cell source, and delivery. Most importantly, we discuss the current limitations and challenges that need to be solved to advance this technology to the translational stage.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Animais , Humanos , Miócitos Cardíacos , Modelos Animais , Regeneração , Diferenciação Celular , Modelos Animais de Doenças
6.
J Am Chem Soc ; 144(36): 16667-16675, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-36047993

RESUMO

Singlet oxygen (1O2)-mediated oxidation represents an attractive strategy for incorporation of oxygen atoms from air under mild and environmentally benign conditions. However, the 1O2 reaction with enamine suffers from fragmentation, leading to very unsuccessful transformation. Here, Lewis acid is introduced to intercept [2 + 2] or "ene" reaction intermediates of the 1O2 reaction and enables oxidative dimerization of enamines to produce pyrrolin-4-ones in good to excellent yields. Mechanistic studies reveal the formation of the imino ketone intermediate from the interaction of 1O2 and enamine, which is able to interact with Lewis acid, relaying the 1O2 reaction in enamine chemistry. For the first time, selective cross-dimerization of two different enamines is achieved. Due to the advantages of mild conditions, high chemoselectivity, and up to 99% yield, a promising strategy has been developed for synthesizing aza-heterocycles under ambient conditions, which can be further applied for the synthesis of imidazolone, quinoxaline, and highly functionalized imine.


Assuntos
Ácidos de Lewis , Oxigênio Singlete , Dimerização , Iminas , Oxirredução
7.
Angew Chem Int Ed Engl ; 61(40): e202209293, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-35912895

RESUMO

Herein, cobaloxime is used for the first time as a catalyst for the synthesis of phosphorylated heteroaromatics, which is an intriguing and versatile functional motif. With visible-light irradiation, cobaloxime not only oxidizes phosphine oxides to form phosphorus radicals (P-radicals) for a subsequent reaction with radical acceptor isocyanides or heteroaromatics, but also combines the radical intermediate with ß-H elimination, thereby producing phosphorylated heteroaromatics with only H2 or CH4 as byproduct. Phosphine oxides with dialkyl, alkylaryl, and diaryl substituents could be directly transformed into phosphorylated phenanthridines, benzothiazoles, isoquinolines, and common heteroaromatics. This catalytic system features extremely mild conditions, broad substrate scope and good to excellent yields. Scale-up reaction and sunlight reaction show the great application potential in the green synthesis of important organophosphorus chemicals.


Assuntos
Cianetos , Óxidos , Benzotiazóis , Isoquinolinas , Compostos Organometálicos , Fenantridinas , Fosfinas , Fósforo
8.
Angew Chem Int Ed Engl ; 61(52): e202208831, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-36202761

RESUMO

A direct strategy for the difunctionalization of alkenes, with acylation occurring at the more substituted alkene position, would be attractive for complex ketone synthesis. We report herein a reaction driven by a single photocatalyst that enables α-acylation in this way with the introduction of a fluoromethyl, alkyl, sulfonyl or thioether group at the ß-position of the alkene with high chemo- and regioselectivity under extremely mild conditions. Crucial to the success of this method are rate differences in the kinetics of radical generation through single-electron transfer (SET) between different radical precursors and the excited photocatalyst (PC*). Thus, the ß-position of the alkene is first occupied by the group derived from the radical precursor that can be generated most readily, and α-keto acids could be used as an electrophilic reagent for the α-acylation of alkenes.


Assuntos
Alcenos , Catálise , Acilação , Indicadores e Reagentes
9.
Appl Environ Microbiol ; 87(8)2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33514518

RESUMO

Shewanella oneidensis is a model strain of the electrochemical active bacteria (EAB) because of its strong capability of extracellular electron transfer (EET) and genetic tractability. In this study, we investigated the effect of carbon sources on EET in S. oneidensis by using reduction of palladium ions (Pd(II)) as a model and found that pyruvate greatly accelerated the Pd(II) reduction compared with lactate by resting cells. Both Mtr pathway and hydrogenases played a role in Pd(II) reduction when pyruvate was used as a carbon source. Furthermore, in comparison with lactate-feeding S. oneidensis, the transcriptional levels of formate dehydrogenases involving in pyruvate catabolism, Mtr pathway, and hydrogenases in pyruvate-feeding S. oneidensis were up-regulated. Mechanistically, the enhancement of electron generation from pyruvate catabolism and electron transfer to Pd(II) explains the pyruvate effect on Pd(II) reduction. Interestingly, a 2-h time window is required for pyruvate to regulate transcription of these genes and profoundly improve Pd(II) reduction capability, suggesting a hierarchical regulation for pyruvate sensing and response in S. oneidensis IMPORTANCE The unique respiration of EET is crucial for the biogeochemical cycling of metal elements and diverse applications of EAB. Although a carbon source is a determinant factor of bacterial metabolism, the research into the regulation of carbon source on EET is rare. In this work, we reported the pyruvate-specific regulation and improvement of EET in S. oneidensis and revealed the underlying mechanism, which suggests potential targets to engineer and improve the EET efficiency of this bacterium. This study sheds light on the regulatory role of carbon sources in anaerobic respiration in EAB, providing a way to regulate EET for diverse applications from a novel perspective.

10.
Angew Chem Int Ed Engl ; 60(51): 26822-26828, 2021 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-34586701

RESUMO

1,4-Dicarbonyl compounds are intriguing motifs and versatile precursors in numerous pharmaceutical molecules and bioactive natural compounds. Direct incorporation of two carbonyl groups into a double bond at both ends is straightforward, but also challenging. Represented herein is the first example of 1,2-dicarbonylation of alkenes by photocatalysis. Key to success is that N(n-Bu)4+ not only associates with the alkyl anion to avoid protonation, but also activates the α-keto acid to undergo electrophilic addition. The α-keto acid is employed both for acyl generation and electrophilic addition. By tuning the reductive and electrophilic ability of the acyl precursor, unsymmetric 1,4-dicarbonylation is achieved for the first time. This metal-free, redox-neutral and regioselective 1,2-dicarbonylation of alkenes is executed by a photocatalyst for versatile substrates under extremely mild conditions and shows great potential in biomolecular and drug molecular derivatization.

11.
Apoptosis ; 24(7-8): 673-685, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31177396

RESUMO

Chemotherapeutic resistance always results in poor clinical outcomes of cancer patients and its intricate mechanisms are large obstacles in overcoming drug resistance. CCR4-NOT transcription complex subunit 3 (CNOT3), a post-translational regulator, is suggested to be involved in cancer development and progression. However, its role in chemotherapeutic resistance is not well understood. In this study, after screening the CNOT3 mRNA in a cancer microarray database called Oncomine and examining the expression levels of CNOT3 mRNA in normal tissues and lung cancer tissues, we found that CNOT3 was up-regulated in lung cancer tissues. Besides, its high-expression was associated with poor prognosis of lung cancer patients. We also found higher expression level of CNOT3 and lower expression level of receptor-interacting protein kinase 3 (RIPK3) in cisplatin-resistant A549 (A549/DDP) cells, and knocking down CNOT3 expression could sensitize A549/DDP cells to cisplatin-induced apoptosis. We demonstrated that CNOT3 depletion up-regulated the expression level of RIPK3 and the enhanced apoptosis was mediated by the elevated RIPK3 to further trigger Caspase 8 activation. Taken together, our results reveal a role of CNOT3 in cisplatin resistance of lung cancer and provide a potential target for lung cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pulmonares/patologia , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Fatores de Transcrição/metabolismo , Células A549 , Caspase 8/metabolismo , Proliferação de Células , Proteína de Domínio de Morte Associada a Fas/metabolismo , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Prognóstico , Fatores de Transcrição/genética
12.
Chemphyschem ; 20(13): 1719-1727, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31090243

RESUMO

Firefly bioluminescence is produced via luciferin enzymatic reactions in luciferase. Luciferin has to be unceasingly replenished to maintain bioluminescence. How is the luciferin reproduced after it has been exhausted? In the early 1970s, Okada proposed the hypothesis that the oxyluciferin produced by the previous bioluminescent reaction could be converted into new luciferin for the next bioluminescent reaction. To some extent, this hypothesis was evidenced by several detected intermediates. However, the detailed process and mechanism of luciferin regeneration remained largely unknown. For the first time, we investigated the entire process of luciferin regeneration in firefly bioluminescence by density functional theory calculations. This theoretical study suggests that luciferin regeneration consists of three sequential steps: the oxyluciferin produced from the last bioluminescent reaction generates 2-cyano-6-hydroxybenzothiazole (CHBT) in the luciferin regenerating enzyme (LRE) via a hydrolysis reaction; CHBT combines with L-cysteine in vivo to form L-luciferin via a condensation reaction; and L-luciferin inverts into D-luciferin in luciferase and thioesterase. The presently proposed mechanism not only supports the sporadic evidence from previous experiments but also clearly describes the complete process of luciferin regeneration. This work is of great significance for understanding the long-term flashing of fireflies without an in vitro energy supply.


Assuntos
Luciferina de Vaga-Lumes/metabolismo , Animais , Cisteína/metabolismo , Vaga-Lumes/química , Vaga-Lumes/enzimologia , Luciferina de Vaga-Lumes/química , Hidrólise , Luciferases de Vaga-Lume/metabolismo , Modelos Químicos , Estereoisomerismo , Tioléster Hidrolases/metabolismo
13.
Chemistry ; 24(37): 9340-9352, 2018 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-29710377

RESUMO

The luciferin/luciferase system of the firefly has been used in bioluminescent imaging to monitor biological processes. In order to enhance the efficiency and expand the application range, some efforts have been made to tune the light emission, especially the effort to obtain NIR light. However, those case-by-case studies have not together revealed the nature and mechanism of the color tuning. In this paper, we theoretically investigated the fluorescence of all kinds of typical oxyluciferin analogues. The present systematical modifications of both oxyluciferin and luciferase indicate that the essential factor affecting the emission color is the charge distribution (or the electric dipole moment) on the oxyluciferin, which impacts on the charge transfer to form the light emitter and, subsequently, influence the strength and wavelength of the emission light. More negative charge distributed on the "thiazolone moiety" of the oxyluciferin or its analogues leads to a redshift. Based on this conclusion, we theoretically designed optimal pairs of luciferin analogue and luciferase for emitting NIR light, which could inspire new synthetic procedures and practical applications.


Assuntos
Corantes Fluorescentes/química , Indóis/química , Medições Luminescentes/métodos , Modelos Moleculares , Pirazinas/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Animais , Luciferina de Vaga-Lumes/química , Fluorescência , Expressão Gênica , Luz , Luciferases de Vaga-Lume/química , Luciferases de Vaga-Lume/genética , Mutação
14.
Appl Microbiol Biotechnol ; 102(24): 10791-10801, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30334090

RESUMO

Iron reduction mediated by Fe(III)-reducing bacteria (FeRB) occurs in aqueous environments and plays an essential role in removing contaminates in polluted freshwater lakes. Two model FeRB species, Shewanella and Geobacter, have been intensively studied because of their functions in bioremediation, iron reduction, and bioelectricity production. However, the abundance and community diversity of Shewanella and Geobacter in eutrophic freshwater lakes remain largely unknown. In this work, the distribution, abundance and biodiversity of Shewanella, Geobacter and other FeRB in the sediments of a heavily polluted lake, Chaohu Lake, China, across four successive seasons were investigated. Shewanella, Geobacter, and other FeRB were found to be widely distributed in the sediment of this heavily eutrophic lake. Geobacter was abundant with at least one order of magnitude more than Shewanella in cold seasons. Three Shewanella-related operational taxonomic units were detected and sixty one Geobacter-related operational taxonomic units were grouped into three phylogenetic clades. Thiobacillus, Desulfuromonas and Geobacter were identified as the main members of FeRB in the lake sediments. Interestingly, nutrients like carbon, nitrogen, and phosphorus were found to be the key factors governing the abundance and diversity of FeRB. Total FeRB, as well as Geobacter and Shewanella, were more abundant in the heavily eutrophic zone than those in the lightly eutrophic zone. The abundance and diversity of FeRB in the sediments of freshwater lakes were highly related with the degree of eutrophication, which imply that FeRB might have a great potential in alleviating the eutrophication and contamination in aqueous environments.


Assuntos
Geobacter , Sedimentos Geológicos/microbiologia , Ferro/metabolismo , Lagos/microbiologia , Shewanella , Bactérias/genética , Bactérias/isolamento & purificação , Biodiversidade , China , Clonagem Molecular , Eutrofização , Geobacter/genética , Geobacter/isolamento & purificação , Sedimentos Geológicos/química , Sequenciamento de Nucleotídeos em Larga Escala , Oxirredução , Filogenia , Shewanella/genética , Shewanella/isolamento & purificação , Microbiologia da Água , Poluição da Água
15.
Cell Mol Life Sci ; 74(10): 1805-1817, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27999898

RESUMO

Mouse embryonic stem cells (mESCs), characterized by their pluripotency and capacity for self-renewal, are driven by a complex gene expression program composed of several regulatory mechanisms. These mechanisms collaborate to maintain the delicate balance of pluripotency gene expression and their disruption leads to loss of pluripotency. In this review, we provide an extensive overview of the key pillars of mESC pluripotency by elaborating on the various essential transcription factor networks and signaling pathways that directly or indirectly support this state. Furthermore, we consider the latest developments in the role of epigenetic regulation, such as noncoding RNA signaling or histone modifications.


Assuntos
Epigênese Genética , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco Embrionárias Murinas/metabolismo , Ativação Transcricional , Animais , Diferenciação Celular , Proliferação de Células , Montagem e Desmontagem da Cromatina , Redes Reguladoras de Genes , Código das Histonas , Camundongos , Células-Tronco Embrionárias Murinas/citologia , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
16.
Appl Environ Microbiol ; 83(4)2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-27986717

RESUMO

Manipulation of biofilm formation in Shewanella is beneficial for application to industrial and environmental biotechnology. BpfA is an adhesin largely responsible for biofilm formation in many Shewanella species. However, the mechanism underlying BpfA production and the resulting biofilm remains vaguely understood. We previously described the finding that BpfA expression is enhanced by DosD, an oxygen-stimulated diguanylate cyclase, under aerobic growth. In the present work, we identify FlrA as a critical transcription regulator of the bpfA operon in Shewanella putrefaciens CN32 by transposon mutagenesis. FlrA acted as a repressor of the operon promoter by binding to two boxes overlapping the -10 and -35 sites recognized by σ70 DosD regulation of the expression of the bpfA operon was mediated by FlrA, and cyclic diguanylic acid (c-di-GMP) abolished FlrA binding to the operon promoter. We also demonstrate that FlhG, an accessory protein for flagellum synthesis, antagonized FlrA repression of the expression of the bpfA operon. Collectively, this work demonstrates that FlrA acts as a central mediator in the signaling pathway from c-di-GMP to BpfA-associated biofilm formation in S. putrefaciens CN32. IMPORTANCE: Motility and biofilm are mutually exclusive lifestyles, shifts between which are under the strict regulation of bacteria attempting to adapt to the fluctuation of diverse environmental conditions. The FlrA protein in many bacteria is known to control motility as a master regulator of flagellum synthesis. This work elucidates its effect on biofilm formation by controlling the expression of the adhesin BpfA in S. putrefaciens CN32 in response to c-di-GMP. Therefore, FlrA plays a dual role in controlling motility and biofilm formation in S. putrefaciens CN32. The cooccurrence of flrA, bpfA, and the FlrA box in the promoter region of the bpfA operon in diverse Shewanella strains suggests that bpfA is a common mechanism that controls biofilm formation in this bacterial species.


Assuntos
Adesinas Bacterianas/genética , Biofilmes/crescimento & desenvolvimento , Proteínas Repressoras/genética , Shewanella putrefaciens/metabolismo , Transcrição Gênica/genética , Adesinas Bacterianas/metabolismo , Proteínas de Bactérias/genética , Sequência de Bases , GMP Cíclico/análogos & derivados , GMP Cíclico/farmacologia , Flagelos/metabolismo , Regulação Bacteriana da Expressão Gênica/genética , Regiões Promotoras Genéticas/genética , Shewanella putrefaciens/genética
17.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 37(2): 225-231, 2017 Feb.
Artigo em Zh | MEDLINE | ID: mdl-30650278

RESUMO

Objective To observe the effects of Xinfeng Capsule (XFC) at different doses on lung function, Thl/Th2 cells, regulatory T cells (Treg) in adjuvant arthritis (AA) rats. Methods Totally 84 rats were randomly divided into 5 groups, i.e., the normal control group (NC) , the model group (M) , the methotrexate (MTX) group, the Tripterygium Glycosides Table (TGT) group, the low dose XFC (XFC- L) group, the medium dose XFC (XFC-M) group, the high dose XFC (XFC-H) group, 12 in each group. Freund's complete adjuvant (FCA; 0. 1 mL) was intradermally injected to all rats except those in the NC group from right rear paw to induce inflammation. Medication was started from the 19th day after inflam- mation. Normal saline was administered to rats in the NC group and the M group. Rats in the rest groups were correspondingly administered with MTX, TGT, XFC, respectively. Changes of each index were ob- served in all groups. Results (1) Compared with the NC group, rat paw swelling degree (E) , arthritis index (AI) , lung index (LI) , average expiratory flow in 1 second (FEV1/FVC%) , alveolitis integral, TNF- α, Th1/Th2 cells, transforming growth factor-ß1 ( TGF-ß1 ) expression significantly increased in the M group (P <0. 01) ; forced vital capacity (FVC) , peak expiratory flow 25% of vital capacity (FEF25), peak expiratory flow 50% of vital capacity (FEF50), peak expiratory flow 75% of vital capacity (FEF75), the maximum mid-expiratory flow (MMF) , peak expiratory flow (PEF) , CD4 ⁺Treg, CD4⁺CD25 ⁺Treg, IL-10, and Foxp3 expression significantly decreased in the M group (P <0. 01). (2) Compared with the M group, body weight, FVC, FEF25, FEF50, FEF75, MMF, PEF, IL-10, Treg, and Foxp3 expression increased in all treatment groups; E, Al, LI, FEV1/FVC%, TNF-α, Th1/Th2 cells, and TGF-ß1 expression decreased in all treatment groups (P <0. 05, P <0. 01). (3) Compared with the XFC-M group, LI, alveolitis integral, TNF- α, Th1/Th2 cells, and TGF-ß1 increased; FVC, FEF25, FEF50, FEF75, IL-10, CD4⁺Treg, CD4⁺CD25⁺ Treg, and Foxp3 decreased in other treatment groups (P <0. 05, P <0. 01). Conclusions AA rats had local swollen paws and decreased lung function. XFC could significantly improve paw swelling and Al of AA rats, and improve lung function. It could reduce inflammatory reaction and immune complexes on tis- sue and organ damage, improve joint and pulmonary symptoms possibly through promoting expressions of IL-10, CD4⁺Treg, CD4⁺CD25⁺Treg, and Foxp3, and inhibiting TNF-α,Th1/Th2 cells, and TGF-ß1 ex- pression.


Assuntos
Artrite Experimental , Medicamentos de Ervas Chinesas , Linfócitos T Reguladores , Animais , Artrite Experimental/tratamento farmacológico , Artrite Experimental/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Pulmão/fisiologia , Ratos , Testes de Função Respiratória , Células Th1 , Células Th2
18.
Phys Chem Chem Phys ; 16(42): 23003-11, 2014 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-25238285

RESUMO

The ability of dissimilatory metal-reducing microorganisms (DMRM) to conduct extracellular electron transfer with conductive cellular components grants them great potential for bioenergy and environmental applications. Crystalline Fe(III) oxide, a type of widespread electron acceptor for DMRM in nature, can be excited by light for photocatalysis and microbial culture-mediated photocurrent production. However, the feasibility of direct electron transfer from living cells to light-excited Fe(III) oxides has not been well documented and the cellular physiology in this process has not been clarified. To resolve these problems, an electrochemical system composed of Geobacter sulfurreducens and hematite (α-Fe2O3) was constructed, and direct electron transfer from G. sulfurreducens cells to the light-excited α-Fe2O3 in the absence of soluble electron shuttles was observed. Further studies evidenced the efficient excitation of α-Fe2O3 and the dependence of photocurrent production on the biocatalytic activity. Light-induced electron transfer on the cell-α-Fe2O3 interface correlated linearly with the rates of microbial respiration and substrate consumption. In addition, the G. sulfurreducens cells were found to survive on light-excited α-Fe2O3. These results prove a direct mechanism behind the DMRM respiration driven by photo-induced charge separation in semiconductive acceptors and also imply new opportunities to design photo-bioelectronic devices with living cells as a catalyst.


Assuntos
Biocatálise/efeitos da radiação , Compostos Férricos/química , Compostos Férricos/metabolismo , Geobacter/metabolismo , Geobacter/efeitos da radiação , Luz , Transporte de Elétrons/efeitos da radiação , Geobacter/química , Geobacter/citologia
19.
Acta Pharmacol Sin ; 35(1): 113-23, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24335836

RESUMO

AIM: The purpose of the present study was to investigate the anticancer activity of bornyl caffeate in the human breast cancer cell line MCF-7. METHODS: The cell viability was determined using the MTT assay, and apoptosis was initially defined by monitoring the morphology of the cell nuclei and staining an early apoptotic biomarker with Annexin V-FITC. The mitochondrial membrane potential was visualized by JC-1 under fluorescence microscopy, whereas intracellular reactive oxygen species (ROS) were assessed by flow cytometry. The expression of apoptosis-associated proteins was determined by Western blotting analysis. RESULTS: Bornyl caffeate induced apoptosis in MCF-7 cells in a dose- and time-dependent manner. Consistently, bornyl caffeate increased Bax and decreased Bcl-xl, resulting in the disruption of MMP and subsequent activation of caspase-3. Moreover, bornyl caffeate triggered the formation of ROS and the activation of the mitogen-activated protein (MAP) kinases p38 and c-Jun N-terminal kinase (JNK). Antioxidants attenuated the activation of MAP kinase p38 but barely affected the activation of JNK. Importantly, the cytotoxicity of bornyl caffeate was partially attenuated by scavenging ROS and inhibited by MAP kinases and caspases. CONCLUSION: The present study demonstrated that bornyl caffeate induced apoptosis in the cancer cell line MCF-7 via activating the ROS- and JNK-mediated pathways. Thus, bornyl caffeate may be a potential anticancer lead compound.


Assuntos
Antineoplásicos/farmacologia , Apoptose/fisiologia , Neoplasias da Mama/metabolismo , Ácidos Cumáricos/farmacologia , Sistema de Sinalização das MAP Quinases/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Apoptose/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Células HeLa , Células Hep G2 , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Células MCF-7 , Células PC12 , Ratos
20.
J Hazard Mater ; 465: 133201, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38113733

RESUMO

Silver (Ag)-containing nanomaterials have emerged as promising alternatives or adjuvants to antibiotics. Ongoing research is dedicated to enhance their antimicrobial efficacy, stability, biocompatibility, and environmental sustainability. Microorganism-synthesized Ag-containing nanomaterials offer distinct advantages, especially for various surface modification, which potentially fulfill these objectives. In this study, we present the synthesis of silver-selenium (Bio-Ag2Se) nanoparticles using a yeast strain, Rhodotorula mucilaginosa PA-1. These Bio-Ag2Se nanoparticles have small size with a narrow size distribution (12.3 ± 2.9 nm) and long-term stability. They demonstrate a broad antimicrobial spectrum and high antimicrobial efficacy at very low concentrations, effectively targeting microorganisms including Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, as well as pathogenic fungus Candida albicans. Furthermore, Bio-Ag2Se nanoparticles exhibit excellent efficacy to inhibit and eliminate biofilms formed by notorious pathogen S. aureus. In contrast, Bio-Ag2Se nanoparticles at effective antibacterial concentrations demonstrate favorable biocompatibility and do not show obvious cytotoxic effects on human and plant cells. To elucidate the antibacterial mechanisms of Bio-Ag2Se nanoparticles against S. aureus and E. coli, transcriptomic analysis and phenotypic examination were employed. The results reveal significant and broad up-regulation in carbon metabolism pathways in both S. aureus and E. coli, suggesting it as one of the major antibacterial mechanisms of Bio-Ag2Se. This study presents a green synthesis strategy for Ag-containing nanoparticles with promising applications.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Humanos , Prata/farmacologia , Staphylococcus aureus/metabolismo , Escherichia coli/metabolismo , Anti-Infecciosos/metabolismo , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
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