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1.
Phys Rev Lett ; 132(12): 126503, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38579234

RESUMO

Beyond 14 GPa of pressure, bilayered La_{3}Ni_{2}O_{7} was recently found to develop strong superconductivity above the liquid nitrogen boiling temperature. An immediate essential question is the pressure-induced qualitative change of electronic structure that enables the exciting high-temperature superconductivity. We investigate this timely question via a numerical multiscale derivation of effective many-body physics. At the atomic scale, we first clarify that the system has a strong charge transfer nature with itinerant carriers residing mainly in the in-plane oxygen between spin-1 Ni^{2+} ions. We then elucidate in electron-volt scale and sub-electron-volt scale the key physical effect of the applied pressure: it induces a cupratelike electronic structure via fractionalizing the Ni ionic spin from 1 to 1/2. This suggests a high-temperature superconductivity in La_{3}Ni_{2}O_{7} with microscopic mechanism and (d-wave) symmetry similar to that in the cuprates.

2.
Angew Chem Int Ed Engl ; : e202409322, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39195347

RESUMO

Metallic zinc has emerged as a promising anode material for high-energy battery systems due to its high theoretical capacity (820 mA h g-1), low redox potential for two-electron reactions, cost-effectiveness and inherent safety. However, current zinc metal batteries face challenges in low coulombic efficiency and limited longevity due to uncontrollable dendrite growth, the corrosive hydrogen evolution reaction (HER) and decomposition of the aqueous ZnSO4 electrolyte. Here, we report an interfacial-engineering approach to mitigate dendrite growth and reduce corrosive reactions through the design of ultrathin selective membranes coated on the zinc anodes. The submicron-thick membranes derived from polymers of intrinsic microporosity (PIMs), featuring pores with tunable interconnectivity, facilitate regulated transport of Zn2+-ions, thereby promoting a uniform plating/stripping process. Benefiting from the protection by PIM membranes, zinc symmetric cells deliver a stable cycling performance over 1500 h at 1 mA/cm² with a capacity of 0.5 mAh while full cells with NaMnO2 cathode operate stably at 1 A g-1 over 300 cycles without capacity decay. Our work represents a new strategy of preparing multi-functional membranes that can advance the development of safe and stable zinc metal batteries.

3.
J Sep Sci ; 46(1): e2200656, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36285382

RESUMO

This paper reports a method for determining the carbonate content in barite ore using headspace gas chromatography. Based on the acidification reaction, the carbonate in the barite ore was converted to CO2 in a closed headspace vial. When the carbonate content was significant, the pressure caused changes in the CO2 and O2 signals and affected the measurement accuracy. It was found that carbonate content is proportional to the intensity ratio of the CO2 to O2 signals. Thus, the carbonate content in barite ore can be measured indirectly using a theoretical model. The results showed that the carbonate in 3 g of barite ore sample with a particle size of 74 µm could react completely with a hydrochloric acid solution (2 mol/L) at 65°C for 5 min. The method described herein had good precision (relative standard deviation < 4.14%) and accuracy (relative differences < 6.12%). Further, the limit of quantification was 0.07 mol/L. Owing to its simplicity and speed, this method can be used for the batch determination of carbonate content in barite ore.


Assuntos
Sulfato de Bário , Dióxido de Carbono , Carbonatos , Ácidos , Cromatografia Gasosa/métodos
4.
Biomed Chromatogr ; 37(5): e5611, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36840461

RESUMO

Biflavonoids are naturally occurring compounds consisting of two flavonoid moieties that have received substantial attention from researchers. Although many kinds of biflavonoids are typically distributed in Selaginella uncinata with hypoglycemic effect, their anti-α-glucosidase activities are not yet clear. In this study, a ligand fishing strategy for fast screening of α-glucosidase inhibitors from S. uncinata was proposed. α-Glucosidase was first immobilized on Fe3 O4 magnetic nanoparticles (MNPs) and then the α-glucosidase-functionalized MNPs were incubated with crude extracts of S. uncinata to fish out the ligands. Furthermore, considering the similarity and easy confusion of the structures of biflavonoids, the fragmentation patterns of different types of biflavonoids were studied. Based on this, 11 biflavonoids ligands with α-glucosidase inhibitory activities were accurately and quickly identified from S. uncinata with ultra-high-performance liquid chromatography-quadrupole time-of-flight-tandem mass spectrometry. Furthermore, these ligands were confirmed to be potential inhibitors through the in vitro inhibitory assay and molecular docking.


Assuntos
Biflavonoides , Selaginellaceae , Animais , alfa-Glucosidases , Biflavonoides/farmacologia , Biflavonoides/química , Cromatografia Líquida de Alta Pressão/métodos , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Ligantes , Simulação de Acoplamento Molecular , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Selaginellaceae/química , Espectrometria de Massas em Tandem/métodos
5.
J Am Chem Soc ; 144(37): 17198-17208, 2022 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-36074146

RESUMO

Redox-active organic materials have emerged as promising alternatives to conventional inorganic electrode materials in electrochemical devices for energy storage. However, the deployment of redox-active organic materials in practical lithium-ion battery devices is hindered by their undesired solubility in electrolyte solvents, sluggish charge transfer and mass transport, as well as processing complexity. Here, we report a new molecular engineering approach to prepare redox-active polymers of intrinsic microporosity (PIMs) that possess an open network of subnanometer pores and abundant accessible carbonyl-based redox sites for fast lithium-ion transport and storage. Redox-active PIMs can be solution-processed into thin films and polymer-carbon composites with a homogeneously dispersed microstructure while remaining insoluble in electrolyte solvents. Solution-processed redox-active PIM electrodes demonstrate improved cycling performance in lithium-ion batteries with no apparent capacity decay. Redox-active PIMs with combined properties of intrinsic microporosity, reversible redox activity, and solution processability may have broad utility in a variety of electrochemical devices for energy storage, sensors, and electronic applications.

6.
Molecules ; 27(11)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35684413

RESUMO

As for ligand fishing, the current immobilization approaches have some potential drawbacks such as the small protein loading capacity and difficult recycle process. The core-shell metal-organic frameworks composite (Fe3O4-COOH@UiO-66-NH2), which exhibited both magnetic characteristics and large specific surface area, was herein fabricated and used as magnetic support for the covalent immobilization of porcine pancreatic lipase (PPL). The resultant composite Fe3O4-COOH@UiO-66-NH2@PPL manifested a high loading capacity (247.8 mg/g) and relative activity recovery (101.5%). In addition, PPL exhibited enhanced tolerance to temperature and pH after immobilization. Then, the composite Fe3O4-COOH@UiO-66-NH2@PPL was incubated with the extract of Scutellaria baicalensis to fish out the ligands. Eight lipase inhibitors were obtained and identified by UPLC-Q-TOF-MS/MS. The feasibility of the method was further confirmed through an in vitro inhibitory assay and molecular docking. The proposed ligand fishing technique based on Fe3O4-COOH@UiO-66-NH2@PPL provided a feasible, selective, and effective platform for discovering enzyme inhibitors from natural products.


Assuntos
Lipase , Estruturas Metalorgânicas , Animais , Enzimas Imobilizadas/química , Ligantes , Lipase/química , Fenômenos Magnéticos , Estruturas Metalorgânicas/química , Simulação de Acoplamento Molecular , Ácidos Ftálicos , Extratos Vegetais/farmacologia , Scutellaria baicalensis , Suínos , Espectrometria de Massas em Tandem
7.
Angew Chem Int Ed Engl ; 61(38): e202207580, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-35876472

RESUMO

Redox flow batteries (RFBs) based on aqueous organic electrolytes are a promising technology for safe and cost-effective large-scale electrical energy storage. Membrane separators are a key component in RFBs, allowing fast conduction of charge-carrier ions but minimizing the cross-over of redox-active species. Here, we report the molecular engineering of amidoxime-functionalized Polymers of Intrinsic Microporosity (AO-PIMs) by tuning their polymer chain topology and pore architecture to optimize membrane ion transport functions. AO-PIM membranes are integrated with three emerging aqueous organic flow battery chemistries, and the synergetic integration of ion-selective membranes with molecular engineered organic molecules in neutral-pH electrolytes leads to significantly enhanced cycling stability.

8.
J Virol ; 94(10)2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32161178

RESUMO

The rabbit hemorrhagic disease virus (RHDV), which belongs to the family Caliciviridae and the genus Lagovirus, causes lethal fulminant hepatitis in rabbits. RHDV decreases the activity of antioxidant enzymes regulated by Nrf2 in the liver. Antioxidants are important for the maintenance of cellular integrity and cytoprotection. However, the mechanism underlying the regulation of the Nrf2-antioxidant response element (ARE) signaling pathway by RHDV remains unclear. Using isobaric tags for relative and absolute quantification (iTRAQ) technology, the current study demonstrated that RHDV inhibits the induction of ARE-regulated genes and increases the expression of the p50 subunit of the NF-κB transcription factor. We showed that RHDV replication causes a remarkable increase in reactive oxygen species (ROS), which is simultaneously accompanied by a significant decrease in Nrf2. It was found that nuclear translocation of Keap1 plays a key role in the nuclear export of Nrf2, leading to the inhibition of Nrf2 transcriptional activity. The p50 protein partners with Keap1 to form the Keap1-p50/p65 complex, which is involved in the nuclear translocation of Keap1. Moreover, upregulation of Nrf2 protein levels in liver cell nuclei by tert-butylhydroquinone (tBHQ) delayed rabbit deaths due to RHDV infection. Considered together, our findings suggest that RHDV inhibits the Nrf2-dependent antioxidant response via nuclear translocation of Keap1-NF-κB complex and nuclear export of Nrf2 and provide new insight into the importance of oxidative stress during RHDV infection.IMPORTANCE Recent studies have reported that rabbit hemorrhagic disease virus (RHDV) infection reduced Nrf2-related antioxidant function. However, the regulatory mechanisms underlying this process remain unclear. The current study showed that the NF-κB p50 subunit partners with Keap1 to form the Keap1-NF-κB complex, which plays a key role in the inhibition of Nrf2 transcriptional activity. More importantly, upregulated Nrf2 activity delayed the death of RHDV-infected rabbits, strongly indicating the importance of oxidative damage during RHDV infection. These findings may provide novel insights into the pathogenesis of RHDV.


Assuntos
Antioxidantes/metabolismo , Infecções por Caliciviridae/metabolismo , Vírus da Doença Hemorrágica de Coelhos/imunologia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Animais , Elementos de Resposta Antioxidante , Antioxidantes/farmacologia , Infecções por Caliciviridae/imunologia , Infecções por Caliciviridae/patologia , Núcleo Celular/metabolismo , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica , Células HEK293 , Vírus da Doença Hemorrágica de Coelhos/patogenicidade , Humanos , Hidroquinonas , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Fígado/lesões , Fígado/metabolismo , Fígado/patologia , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo , Proteômica , Coelhos , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA , Replicação Viral
10.
Nat Mater ; 19(2): 195-202, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31792424

RESUMO

Membranes with fast and selective ion transport are widely used for water purification and devices for energy conversion and storage including fuel cells, redox flow batteries and electrochemical reactors. However, it remains challenging to design cost-effective, easily processed ion-conductive membranes with well-defined pore architectures. Here, we report a new approach to designing membranes with narrow molecular-sized channels and hydrophilic functionality that enable fast transport of salt ions and high size-exclusion selectivity towards small organic molecules. These membranes, based on polymers of intrinsic microporosity containing Tröger's base or amidoxime groups, demonstrate that exquisite control over subnanometre pore structure, the introduction of hydrophilic functional groups and thickness control all play important roles in achieving fast ion transport combined with high molecular selectivity. These membranes enable aqueous organic flow batteries with high energy efficiency and high capacity retention, suggesting their utility for a variety of energy-related devices and water purification processes.

11.
Microb Pathog ; 129: 74-77, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30710674

RESUMO

Pasteurella multocida is the causative agent of a wide range of disease (pasteurellosis) and a zoonotic pathogen in humans. Some pathogenic bacteria are able to exploit host plasminogen for migration across tissue barriers or evade from host innate immunity. However, there is no study on host plasminogen exploitation of P. multocida. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) has been reported to be a plasminogen receptor in many pathogenic bacteria, but its role in P. multocida exploiting plasminogen has not yet been characterized. The aim of this study was to detect the activity of P. multocida to exploit host plasminogen and evaluate the ability of GAPDH to act as a receptor in the recruitment process. P. multocida could recruit host plasminogen and exhibited plasmin activity when stimulated by urokinase. GAPDH exhibited binding activity to plasminogen. GAPDH Antiserum significantly decrease the plasminogen recruitment activity of P. multocida. In conclusion, P. multocida is able to exploit host plasminogen via GAPDH. To our knowledge, this is the first report on host plasminogen exploitation of P. multocida.


Assuntos
Proteínas de Bactérias/metabolismo , Fibrinolíticos/metabolismo , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/metabolismo , Pasteurella multocida/metabolismo , Pasteurella multocida/patogenicidade , Plasminogênio/metabolismo , Animais , Feminino , Humanos , Camundongos Endogâmicos BALB C , Ligação Proteica
12.
Arch Virol ; 162(1): 269-272, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27664029

RESUMO

Rabbit hemorrhagic disease (RHD) is an acute fatal disease caused by the lagovirus rabbit hemorrhagic disease virus (RHDV), which was first reported in 1984 in China. Genetic characterization of RHDV has demonstrated that two different genogroups (G2 and G6) are present in China. To gain a better understanding of the molecular evolution of RHDV, we searched for recombination events by analyzing all full-length RHDV capsid VP60 sequences of Chinese isolates belonging to the genogroups 2 and 6. Our results revealed a recombinant origin for the NanBu/China/2011 isolate. This recombination event occurred between G2 and G6 strains with two breakpoints located at nucleotide positions 393 and 1079 of the VP60 sequence. Phylogenetically, the NanBu/China/2011 strain clustered with genogroup G6 in the entire capsid gene sequence except in the fragment between nucleotides 394 and 1078, where it clustered with genogroup G2. As the consequences of the presence of a G2/G6 recombinant strain in China are unpredictable, the circulation of RHDV in the populations should be carefully monitored.


Assuntos
Infecções por Caliciviridae/veterinária , Evolução Molecular , Genótipo , Vírus da Doença Hemorrágica de Coelhos/genética , Recombinação Genética , Animais , Infecções por Caliciviridae/virologia , China , Análise por Conglomerados , Vírus da Doença Hemorrágica de Coelhos/isolamento & purificação , Filogenia , Coelhos , Análise de Sequência de DNA , Proteínas Estruturais Virais/genética
13.
Arch Virol ; 162(11): 3425-3430, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28780630

RESUMO

During infection host histo-blood group antigens (HBGAs) act as attachment factors that interact with rabbit hemorrhagic disease virus (RHDV) and participate in the infectious process. In the present study, baculovirus expressing recombinant RHDV capsid protein (VP60r) as a vaccine immunogen was used to test its antigenicity and immunogenicity via immunization experiments. Each group of rabbits immunized with VP60r was found to be fully protected against RHDV challenge. The duration of immunity of the vaccine following the inoculation of a single dose was determined to be at least 240 days. RHDV-specific humoral responses in antisera from inoculated rabbits were analyzed using VP60r virus-like particle (VLP)-based ELISA. Anti-VP60-specific antibody was produced by 7 days post-primary immunization. Following this stage, the levels of this antibody increased steadily, peaking at 90 days and maintaining a high level until 240 days. We developed a synthetic carbohydrate assay to detect blockage in attachment of RHDV VLPs to HBGAs by the rabbit antisera. On day 7 post-immunization, serum samples were demonstrated to block the binding of H type 2 to RHDV VLPs, with a blocking rate of almost 60%, a value that then increased steadily over time. From day 60 to day 240 post-immunization, serum samples completely blocked the binding of H type 2 to RHDV VLPs, with a blocking rate of almost 100%. This indicated that VP60-induced antibodies neutralize the interaction of RHDV with HBGAs.


Assuntos
Antígenos de Grupos Sanguíneos/classificação , Infecções por Caliciviridae/veterinária , Vírus da Doença Hemorrágica de Coelhos , Soros Imunes/imunologia , Coelhos/sangue , Vacinas Virais/imunologia , Animais , Antígenos de Grupos Sanguíneos/química , Antígenos de Grupos Sanguíneos/metabolismo , Infecções por Caliciviridae/prevenção & controle , Infecções por Caliciviridae/virologia , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Regulação Viral da Expressão Gênica/fisiologia , Ligação Proteica
14.
J Gen Virol ; 97(2): 356-365, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26612210

RESUMO

Rabbit haemorrhagic disease, caused by rabbit hemorrhagic disease virus (RHDV), results in the death of millions of adult rabbits worldwide, with a mortality rate that exceeds 90%. The sole capsid protein, VP60, is divided into shell (S) and protruding (P) domains, and the more exposed P domain likely contains determinants for cell attachment and antigenic diversity. Nine mAbs against VP60 were screened and identified. To map antigenic epitopes, a set of partially overlapping and consecutive truncated proteins spanning VP60 were expressed. The minimal determinants of the linear B-cell epitopes of VP60 in the P domain, N(326)PISQV(331), D(338)MSFV(342) and K(562)STLVFNL(569), were recognized by one (5H3), four (1B8, 3D11, 4C2 and 4G2) and four mAbs (1D4, 3F7, 5G2 and 6B2), respectively. Sequence alignment showed epitope D(338)MSFV(342) was conserved among all RHDV isolates. Epitopes N(326)PISQV(331) and K(562)STLVFNL(569) were highly conserved among RHDV G1-G6 and variable in RHDV2 strains. Previous studies demonstrated that native viral particles and virus-like particles (VLPs) of RHDV specifically bound to synthetic blood group H type 2 oligosaccharides. We established an oligosaccharide-based assay to analyse the binding of VP60 and epitopes to histo-blood group antigens (HBGAs). Results showed VP60 and its epitopes (aa 326-331 and 338-342) in the P2 subdomain could significantly bind to blood group H type 2. Furthermore, mAbs 1B8 and 5H3 could block RHDV VLP binding to synthetic H type 2. Collectively, these two epitopes might play a key role in the antigenic structure of VP60 and interaction of RHDV and HBGA.


Assuntos
Antígenos de Grupos Sanguíneos/metabolismo , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito B/metabolismo , Vírus da Doença Hemorrágica de Coelhos/imunologia , Proteínas Estruturais Virais/imunologia , Proteínas Estruturais Virais/metabolismo , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/isolamento & purificação , Mapeamento de Epitopos , Feminino , Camundongos Endogâmicos BALB C , Ligação Proteica , Mapeamento de Interação de Proteínas , Coelhos
15.
Cochrane Database Syst Rev ; (9): CD010066, 2015 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-26407098

RESUMO

BACKGROUND: Pulmonary arterial hypertension (PAH) is one of several forms of pulmonary hypertension: a chronic disease of the pulmonary vasculature. The mean age at diagnosis is around 50 years old, with increasing prevalence in people over 70 years old (10% to 17%). The median survival to be approximately seven years with one-, three-, five-, and seven-year survival rates from time of diagnostic right-sided heart catheterization were 85%, 68%, 57%, and 49%, respectively. Several studies showed that calcium channel blockers (CCBs) reduce right ventricular hypertrophy and improve long-term haemodynamics in PAH. OBJECTIVES: To evaluate the clinical efficacy and harms of CCBs for people with PAH. SEARCH METHODS: The search strategy was provided by the Cochrane Airways Group Trials Search Co-ordinator. The following databases were searched from their inception until September 2014: the Cochrane Airways Group Register of Trials (CAGR); the Cochrane Central Register of Controlled Clinical Trials (CENTRAL) (The Cochrane Library,Issue 8 2014); MEDLINE (1948 to September 2014); EMBASE (1974 to September 2014); ClinicalTrials.gov; WHO trial portal; the Chinese Biomedical Databases (1979 to September 2014); CNKI: the Chinese Journals Full Text Database (1979 to September 2014), the Chinese Journals Full Text Database Century Journals (1979 to September 2014), the Chinese Doctoral Degree Thesis Full Text Database (1979 to September 2014), the Chinese Outstanding Master Degree Thesis Full Text Database (1979 to September 2014); VIP Database (1989 to September 2014) and WANFANG Database (1993 to September 2014). No language restriction was applied. SELECTION CRITERIA: Fully published randomized controlled trials (RCTs) comparing CCBs with placebo or other treatment, or comparing CCBs as an adjunct to other treatments with other treatments alone, in patients with PAH. DATA COLLECTION AND ANALYSIS: We used standard methods expected by Cochrane. MAIN RESULTS: We found one RCT to include in this review but it was published only in abstract form with no data for evaluation. AUTHORS' CONCLUSIONS: Currently, as there is lack of valid evidence, the efficacy and safety of CCBs is unproven in the treatment of PAH. However, the search strategy used for this review did identify four controlled clinical trials without randomization, three of which suggested treatment with CCBs may be beneficial in PAH. No adverse side effects of CCBs were reported. Confirmation of these findings by RCTs is recommended.


Assuntos
Bloqueadores dos Canais de Cálcio/uso terapêutico , Hipertensão Pulmonar/tratamento farmacológico , Idoso , Benzimidazóis/uso terapêutico , Benzoatos/uso terapêutico , Humanos , Pessoa de Meia-Idade , Nifedipino/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Telmisartan
16.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(7): 731-5, 2015 Jul.
Artigo em Zh | MEDLINE | ID: mdl-26182281

RESUMO

OBJECTIVE: To investigate the effects of rapamycin (RAP) on pulmonary hypertension (PH) in rats, and to provide new insights into medication selection for the clinical treatment of PH. METHODS: Fifty male Sprague-Dawley rats were randomly divided into blank control, PH model, solvent control, RAP 1, and RAP 2 groups. A rat model of PH was induced by left pneumonectomy (PE) and monocrotaline (MCT). At 5 days after PH model establishment, the solvent control group and the RAP 1 group received an intramuscular injection of solvent and RAP, respectively. At 35 days after PH model establishment, the RAP 2 group received an intramuscular injection of RAP. The mean pulmonary artery pressure (mPAP) and the right ventricle/left ventricle plus septum weight ratio (RV/LV+S) were measured in each group. Histopathological changes in the right lung were evaluated by hematoxylin-eosin (HE) staining. The relative expression of alpha-smooth muscle actin (α-SMA) and smooth muscle protein 22-alpha (SM22α) in each group was determined using real-time PCR. RESULTS: At 35 days after surgery, the PH model and the solvent control groups had significantly higher mPAP and RV/LV+S than the blank control group, while the RAP 1 and the RAP 2 groups had significantly lower mPAP than the solvent control group (P<0.05). The RV/LV+S in the RAP 1 group was significantly lower than that in the solvent control group (P<0.05); however, there was no significant difference in RV/LV+S between the RAP 2 and the solvent control groups (P>0.05). HE staining in the right lung showed the substantially thickened pulmonary artery wall and narrowed arterial lumen in the PH model and the solvent control groups compared with the blank control group. Different degrees of reversal of the pulmonary artery wall thickening were observed after RAP administration. The results of real-time PCR revealed that the relative expression of α-SMA and SM22α in the PH model and the solvent control groups was significantly lower than in the blank control group, while the relative expression of α-SMA and SM22α in the RAP 1 and the RAP 2 groups was significantly higher than in the solvent control group (P<0.05). CONCLUSIONS: RAP can reverse the increase in pulmonary artery pressure and the right ventricular hypertrophy probably by regulation of the phenotypic conversion of vascular smooth muscle cells.


Assuntos
Hipertensão Pulmonar/tratamento farmacológico , Sirolimo/uso terapêutico , Actinas/genética , Animais , Hemodinâmica , Hipertensão Pulmonar/fisiopatologia , Hipertrofia Ventricular Direita/etiologia , Masculino , Proteínas dos Microfilamentos/genética , Proteínas Musculares/genética , Artéria Pulmonar/patologia , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley
17.
Zhongguo Dang Dai Er Ke Za Zhi ; 16(6): 648-53, 2014 Jun.
Artigo em Zh | MEDLINE | ID: mdl-24927445

RESUMO

OBJECTIVE: To study the changes of Hes-1, the target gene of Notch signaling pathway, and its relationship with airway inflammation and remodeling in a rat model of asthma. METHODS: Forty-eight rats were randomly divided into an asthma group and a control group. The rats in the asthma group were sensitized and challenged by ovalbumin (OVA), and normal saline was used in the control group. Two groups were further divided into 3 subgroups according to time points after challenging, i.e. 4 weeks, 8 weeks and 12 weeks (n=8 rats each). Pathological changes of lungs were observed by light microscopy and the thickness of bronchial smooth muscle layer (Wam) was measured. The levels of IL-4 and INF-γ in rat serum and bronchoalveolar lavage fluids (BALF) were measured using ELISA. Expression levels of Hes-1 protein and mRNA were determined by immunohistochemistry and quantitative real-time PCR respectively. RESULTS: Together with the extension of challenging, the Wam of rats in the asthma group increased, a decrease of INF-γ level and an increase of IL-4 level in serum and BALF were also observed, and the differences were statistically significant compared with those in the corresponding control group (P<0.05). Hes-1 protein and mRNA levels also increased gradually after OVA challenging and were higher than those in the control group (P<0.05). The levels of Hes-1 protein and mRNA were positively correlated with Wam and IL-4 in serum and BALF, but were inversely correlated with INF-γ in serum and BALF (P<0.05). CONCLUSIONS: Levels of Hes-1 protein and mRNA increased, which were closely related with the levels of airway inflammatory factors and remodeling of airway smooth muscle. Hes-1 may play an important role in the pathogenesis of asthma.


Assuntos
Remodelação das Vias Aéreas , Asma/etiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Proteínas de Homeodomínio/fisiologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/análise , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Modelos Animais de Doenças , Proteínas de Homeodomínio/análise , Proteínas de Homeodomínio/genética , Interferon gama/análise , Interleucina-4/análise , Masculino , Ratos , Ratos Sprague-Dawley , Fatores de Transcrição HES-1
18.
J Mater Chem B ; 12(3): 667-677, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38063821

RESUMO

Ferroptosis is a non-apoptotic form of cell death that is dependent on the accumulation of intracellular iron that causes elevation of toxic lipid peroxides. Therefore, it is crucial to improve the levels of intracellular iron and reactive oxygen species (ROS) in a short time. Here, we first propose ultrasound (US)-propelled Janus nanomotors (Au-FeOx/PEI/ICG, AFPI NMs) to accelerate cellular internalization and induce cancer cell ferroptosis. This nanomotor consists of a gold-iron oxide rod-like Janus nanomotor (Au-FeOx, AF NMs) and a photoactive indocyanine green (ICG) dye on the surface. It not only exhibits accelerating cellular internalization (∼4-fold) caused by its attractive US-driven propulsion but also shows good intracellular motion behavior. In addition, this Janus nanomotor shows excellent intracellular ROS generation performance due to the synergistic effect of the "Fenton or Fenton-like reaction" and the "photochemical reaction". As a result, the killing efficiency of actively moving nanomotors on cancer cells is 88% higher than that of stationary nanomotors. Unlike previous passive strategies, this work is a significant step toward accelerating cellular internalization and inducing cancer-cell ferroptosis in an active way. These novel US-propelled Janus nanomotors with strong propulsion, efficient cellular internalization and excellent ROS generation are suitable as a novel cell biology research tool.


Assuntos
Ferroptose , Neoplasias , Espécies Reativas de Oxigênio , Ferro , Neoplasias/diagnóstico por imagem
19.
Lancet Reg Health West Pac ; 48: 101133, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39040038

RESUMO

Background: Since the initial identification of the Severe Fever with Thrombocytopenia Syndrome (SFTS) in ticks in rural areas of China in 2009, the virus has been increasingly isolated from a diverse array of hosts globally, exhibiting a rising trend in incidence. This study aims to conduct a systematic analysis of the temporal and spatial distribution of SFTS cases, alongside an examination of the infection rates across various hosts, with the objective of addressing public concerns regarding the spread and impact of the disease. Methods: In this systematic review and meta-analysis, an exhaustive search was conducted across multiple databases, including PubMed, Web of Science, Embase, and Medline, CNKI, WanFang, and CQVIP. The literature search was confined to publications released between January 1, 2009, and May 29, 2023. The study focused on collating data pertaining to animal infections under natural conditions and human infection cases reported. Additionally, species names were unified using the National Center for Biotechnology Information (NCBI) database. The notification rate, notification death rate, case fatality rate, and infection rates (or MIR) were assessed for each study with available data. The proportions were pooled using a generalized linear mixed-effects model (GLMM). Meta-regressions were conducted for subgroup analysis. This research has been duly registered with PROSPERO, bearing the registration number CRD42023431010. Findings: We identified 5492 studies from database searches and assessed 238 full-text studies for eligibility, of which 234 studies were included in the meta-analysis. For human infection data, the overall pooled notification rate was 18.93 (95% CI 17.02-21.05) per ten million people, the overall pooled notification deaths rate was 3.49 (95% CI 2.97-4.10) per ten million people, and the overall pooled case fatality rate was 7.80% (95% CI 7.01%-8.69%). There was an increasing trend in notification rate and deaths rate, while the case fatality rate showed a significant decrease globally. Regarding animal infection data, among 94 species tested, 48 species were found to carry positive nucleic acid or antibodies. Out of these, 14 species were classified under Arthropoda, while 34 species fell under Chordata, comprising 27 Mammalia and 7 Aves. Interpretation: This systematic review and meta-analysis present the latest global report on SFTS. In terms of human infections, notification rates and notification deaths rates are on the rise, while the case fatality rate has significantly decreased. More SFTSV animal hosts have been discovered than before, particularly among birds, indicating a potentially broader transmission range for SFTSV. These findings provide crucial insights for the prevention and control of SFTS on a global scale. Funding: None.

20.
Food Funct ; 14(4): 1952-1961, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36723126

RESUMO

In this study, a ligand fishing technique based on magnetic mesoporous silicon was established and used to screen α-glucosidase inhibitors from Pueraria lobata. To clarify quantity-activity relationships in a holistic view, the knock-out/knock-in technology was used to analyse the interactions of several active constituents in P. lobata. Magnetic mesoporous silicon with a large specific surface area and better biocompatibility was synthesised. Subsequently, α-glucosidase was immobilised on -NH2-modified magnetic mesoporous silicon, and the compounds in the crude extract of P. lobata were screened across enzyme binding. The structures of the ligands were elucidated using UPLC-Q-TOF-MS/MS, and their activities were verified by knock-out/knock-in experiments and molecular docking. Daidzein and puerarin showed α-glucosidase inhibitory activities with an IC50 of 0.088 ± 0.003 mg mL-1 and 0.414 ± 0.005 mg mL-1, respectively. Among them, puerarin, which accounted for more than 40% of the total content, showed synergistic effects with other components and was the main contributor to the α-glucosidase inhibitory activity of P. lobata.


Assuntos
Isoflavonas , Pueraria , alfa-Glucosidases/metabolismo , Inibidores de Glicosídeo Hidrolases/química , Isoflavonas/farmacologia , Ligantes , Fenômenos Magnéticos , Simulação de Acoplamento Molecular , Extratos Vegetais/farmacologia , Pueraria/química , Saccharomyces cerevisiae/metabolismo , Silício , Espectrometria de Massas em Tandem , Tecnologia
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