RESUMO
The effects of sulfur dioxide (SO2) in the catalytic purification of short-chain hydrocarbons are still controversial, and the exact role of SO2 on adsorption and reaction pathways during the catalytic oxidation of different volatile organic compounds (VOCs) remains unclear. Herein, a three-dimensional ordered macroporous Ce0.8Zr0.2O2 supported Pt nanoparticle monolithic catalyst (Pt/OM CZO) was synthesized to investigate these effects. Our findings uncover the diverse effects of SO2: Upon SO2 treatment, the coupling between the S 3p and Pt 5d orbitals promotes the Pt-O-SO3 structure in situ formed on the catalyst surface. The propene (C3H6) molecule readily binds with the oxygen atom in Pt-O-SO3, resulting in the accumulation of acetone and carbon deposition, thereby hindering C3H6 oxidation. Conversely, a cleaved oxygen atom within the Pt-O-SO3 structure enhances propane (C3H8) adsorption and activates the C-H bond, facilitating C3H8 oxidation. These insights are pivotal for advancing the frontier of sulfur-tolerant catalysts, addressing both economic and environmental challenges.
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Oxirredução , Dióxido de Enxofre , Catálise , Dióxido de Enxofre/química , Platina/química , Compostos Orgânicos Voláteis/química , Adsorção , Oxigênio/químicaRESUMO
BACKGROUND: This first-in-human study evaluated HRS-1780, an oral selective non-steroidal mineralocorticoid receptor antagonist, in healthy men. RESEARCH DESIGN AND METHODS: In single ascending dose (SAD) part, 10 participants for each dose cohort (5, 10, 20, 40, 60, and 80 mg) were randomized (8:2) to HRS-1780 or placebo. In multiple ascending dose part, 12 participants for each dose (10, 20, and 40 mg) were randomized (9:3) to HRS-1780 or placebo once daily for 7 days. The primary endpoint was safety and tolerability. RESULTS: HRS-1780 was well tolerated with all adverse events being mild. In the steady state, the median time to maximum concentration (Tmax) was 0.750 h and mean half-life was 1.76-1.96 h. High-fat/high-calorie meal prolonged Tmax but did not affect exposure. Multiple dosing of HRS-1780 at 40 mg showed a decreasing trend in systolic blood pressure compared with placebo. Changes in plasma aldosterone and norepinephrine with HRS-1780 were higher compared to placebo. Upper bounds of two-sided 90% confidence interval of placebo-adjusted change-from-baseline QTcF were below 10 msec at the maximum concentration in SAD. The trial had limited sample size and short study duration. CONCLUSIONS: HRS-1780 had favorable safety and pharmacokinetic profiles and did not cause clinically meaningful QTcF prolongation. TRIAL REGISTRATION: ClinicalTrials.gov (NCT05638126).
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Relação Dose-Resposta a Droga , Antagonistas de Receptores de Mineralocorticoides , Humanos , Masculino , Antagonistas de Receptores de Mineralocorticoides/administração & dosagem , Antagonistas de Receptores de Mineralocorticoides/efeitos adversos , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Antagonistas de Receptores de Mineralocorticoides/farmacocinética , Adulto , Método Duplo-Cego , Adulto Jovem , Meia-Vida , Pessoa de Meia-Idade , Administração Oral , Eletrocardiografia , Interações Alimento-DrogaRESUMO
BACKGROUND: Accumulating evidence has shown that the NOD-like receptor protein 3 (NLRP3) inflammasome plays a crucial role in the inflammatory cascades involved in the development of acute pancreatitis (AP). However, the specific agonist responsible for activating the NLRP3 inflammasome in this process has not yet been identified. The purpose of this study is to clarify whether heparan sulfate (HS) works as an NLRP3 inflammasome activator to evoke inflammatory cascades in the progression of AP. METHODS: Two experimental mouse models of AP were utilized to investigate the pro-inflammatory activity of HS in the development of AP by measuring the secretion of inflammatory cytokines and the neutrophil infiltration in pancreatic tissue. The ability of HS to activate the NLRP3 inflammasome was evaluated both in vitro and in vivo. The nuclear factor kappa B (NF-κB)-mediated expression of NLRP3 inflammasome components in response to HS treatment was determined to decipher the role of HS in transcriptional priming of NLRP3 inflammasome. Furthermore, HS-triggered deubiquitination of NLRP3 was analyzed to reveal the promoting effect of HS on the NLRP3 inflammasome priming via a non-transcriptional pathway. RESULTS: High plasma level of HS was observed with a positive correlation to that of inflammatory cytokines in AP mice. Administration of HS to mice resulted in an exacerbated inflammatory profile, while reducing HS production by an inhibitor of heparanase significantly attenuated inflammatory response. Pharmacological inhibition or genetic deletion of NLRP3 substantially suppressed the HS-stimulated elevation of IL-1ß levels in AP mice. The in vitro data demonstrated that HS primarily serves as a priming signal for the activation of the NLRP3 inflammasome. HS possesses the ability to increase the transcriptional activity of NF-κB and TLR4/NF-κB-driven transcriptional pathway is employed for NLRP3 inflammasome priming. Moreover, HS-induced deubiquitination of NLRP3 is another pathway responsible for non-transcriptional priming of NLRP3 inflammasome. CONCLUSIONS: Our current work has unveiled HS as a new activator of the NLRP3 inflammasome responsible for the secondary inflammatory cascades during the development of AP, highlighting the HS-NLRP3 pathway as a potential target for future preventive and therapeutic approaches of AP.
Assuntos
Modelos Animais de Doenças , Heparitina Sulfato , Inflamassomos , NF-kappa B , Proteína 3 que Contém Domínio de Pirina da Família NLR , Pancreatite , Animais , Masculino , Camundongos , Doença Aguda , Citocinas/metabolismo , Heparitina Sulfato/metabolismo , Inflamassomos/metabolismo , Inflamação/metabolismo , Camundongos Endogâmicos C57BL , Infiltração de Neutrófilos/efeitos dos fármacos , NF-kappa B/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Pancreatite/metabolismoRESUMO
Ground-level ozone (O3) pollution has emerged as a significant concern due to its detrimental effects on human health and the ecosystem. Catalytic removal of O3 has proven to be the most efficient and cost-effective method. However, its practical application faces substantial challenges, particularly in relation to its effectiveness across the entire humidity range. Herein, we proposed a novel strategy termed "dual active sites" by employing graphitized carbon-loaded core-shell cobalt catalysts (Co@Co3O4-C). Co@Co3O4-C was synthesized via the pyrolysis of a Co-organic ligand as the precursor. By utilizing this approach, we achieved a nearly constant 100% working efficiency of the Co@Co3O4-C catalyst for catalyzing O3 decomposition across the entire humidity range. Physicochemical characterization coupled with density functional theory calculations elucidates that the presence of encapsulated metallic Co nanoparticles enhances the reactivity of the cobalt oxide capping layer. Additionally, the interface carbon atom, strongly influenced by adjacent metallic Co nuclei, functions as a secondary active site for the decomposition of O3 decomposition. The utilization of dual active sites effectively mitigates the competitive adsorption of H2O molecules, thus isolating them for adsorption in the cobalt oxide capping layer. This optimized configuration allows for the decomposition of O3 without interference from moisture. Furthermore, O3 decomposition monolithic catalysts were synthesized using a material extrusion-based three-dimensional (3D) printing technology, which demonstrated a low pressure drop and exceptional mechanical strength. This work provides a "dual active site" strategy for the O3 decomposition reaction, realizing O3 catalytic decomposition over the entire humidity range.
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Umidade , Ozônio , Ozônio/química , Catálise , Grafite/química , Cobalto/química , Carbono/química , ÓxidosRESUMO
The development of highly efficient catalysts for formaldehyde (HCHO) oxidation is of significant interest for the improvement of indoor air quality. Up to 400 works relating to the catalytic oxidation of HCHO have been published to date; however, their analysis for collective inference through conventional literature search is still a challenging task. A machine learning (ML) framework was presented to predict catalyst performance from experimental descriptors based on an HCHO oxidation catalysts database. MnOx, CeO2, Co3O4, TiO2, FeOx, ZrO2, Al2O3, SiO2, and carbon-based catalysts with different promoters were compiled from the literature. Notably, 20 descriptors including reaction catalyst composition, reaction conditions, and catalyst physical properties were collected for data mining (2263 data points). Furthermore, the eXtreme Gradient Boosting algorithm was employed, which successfully predicted the conversion efficiency of HCHO with an R-square value of 0.81. Shapley additive analysis suggested Pt/MnO2 and Ag/Ce-Co3O4 exhibited excellent catalytic performance of HCHO oxidation based on the analysis of the entire database. Validated by experimental tests and theoretical simulations, the key descriptor identified by ML, i.e., the first promoter, was further described as metal-support interactions. This study highlights ML as a useful tool for database establishment and the catalyst rational design strategy based on the importance of analysis between experimental descriptors and the performance of complex catalytic systems.
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Poluição do Ar em Ambientes Fechados , Formaldeído , Aprendizado de Máquina , Oxirredução , Formaldeído/química , CatáliseRESUMO
OBJECTIVE: SHR-1703 is a novel humanized IgG1 monoclonal antibody with high IL-5 affinity and prolonged half-life, aiming to control eosinophil-related diseases. The study intended to evaluate pharmacokinetics, pharmacodynamics, immunogenicity, safety, and tolerability of SHR-1703 in healthy subjects. METHODS: A single-center, randomized, double-blind, placebo-controlled, single-dose escalation phase I study was conducted. 42 subjects were allocated to sequentially receive single subcutaneous injection of 20, 75, 150, 300, and 400 mg SHR-1703 or placebo. RESULTS: After administration, SHR-1703 was slowly absorbed with median Tmax ranging from 8.5 to 24.5 days. Mean t1/2 in 150 to 400 mg doses was 86 to 100 days. Cmax and AUC increased in nearly dose-proportional pattern over range of 75 to 400 mg SHR-1703. After receiving SHR-1703, peripheral blood eosinophils (EOS) greatly decreased from baseline, which showed no significant change from baseline in placebo group. Magnitude and duration of reduction of EOS rose with increased dosing of SHR-1703. In 400 mg dose, remarkable efficacy of reducing EOS maintained up to approximately 6 months post single administration. Moreover, SHR-1703 exhibited low immunogenicity (2.9%), favorable safety, and tolerability in healthy subjects. CONCLUSION: Pharmacokinetics, pharmacodynamics, immunogenicity, safety, and tolerability of SHR-1703 support further clinical development of SHR-1703 in eosinophil-associated diseases. CLINICAL TRIAL REGISTRATION: The study was registered on the ClinicalTrials.gov (identifier: NCT04480762).
Assuntos
Anticorpos Monoclonais Humanizados , Relação Dose-Resposta a Droga , Eosinófilos , Interleucina-5 , Humanos , Método Duplo-Cego , Masculino , Adulto , Feminino , Eosinófilos/efeitos dos fármacos , Adulto Jovem , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/farmacocinética , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/farmacologia , Interleucina-5/antagonistas & inibidores , Interleucina-5/imunologia , Meia-Vida , Injeções Subcutâneas , Pessoa de Meia-Idade , Área Sob a Curva , Voluntários SaudáveisRESUMO
Particulate matter, represented by soot particles, poses a significant global environmental threat, necessitating efficient control technology. Here, we innovatively designed and elaborately fabricated ordered hierarchical macroporous catalysts of Ce0.8Zr0.2O2 (OM CZO) integrated on a catalyzed diesel particulate filter (CDPF) using the self-assembly method. An oxygen-vacancy-enriched ordered macroporous Ce0.8Zr0.2O2 catalyst (VO-OM CZO) integrated CDPF was synthesized by subsequent NaBH4 reduction. The VO-OM CZO integrated CDPF exhibited a markedly enhanced soot oxidation activity compared to OM CZO and powder CZO coated CDPFs (T50: 430 vs 490 and 545 °C, respectively). The well-defined OM structure of the VO-OM CZO catalysts effectively improves the contact efficiency between soot and the catalysts. Meanwhile, oxygen vacancies trigger the formation of a large amount of highly reactive peroxide species (O22-) from molecular oxygen (O2) through electron abstraction from the three adjacent Ce3+ (3Ce3+ + Vö + O2 â 3Ce4+ + O22-), contributing to the efficient soot oxidation. This work demonstrates the fabrication of the ordered macroporous CZO integrated CDPF and reveals the importance of structure and surface engineering in soot oxidation, which sheds light on the design of highly efficient PM capture and removal devices.
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Oxirredução , Catálise , Peróxidos/química , Fuligem/química , Filtração , Material Particulado/química , Emissões de VeículosRESUMO
Graphdiyne (GDY)-based materials, owing to their unique structure and tunable electronic properties, exhibit great potential in the fields of catalysis, energy, environmental science, and beyond. In particular, GDY/metal oxide hybrid materials (GDY/MOs) have attracted extensive attention in energy and environmental catalysis. The interaction between GDY and metal oxides can increase the number of intrinsic active sites, facilitate charge transfer, and regulate the adsorption and desorption of intermediate species. In this review, we summarize the structure, synthesis, advanced characterization, small molecule activation mechanism and applications of GDY/MOs in energy conversion and environmental remediation. The intrinsic structure-activity relationship and corresponding reaction mechanism are highlighted. In particular, the activation mechanisms of reactant molecules (H2O, O2, N2, etc.) on GDY/MOs are systemically discussed. Finally, we outline some new perspectives of opportunities and challenges in developing GDY/MOs for efficient energy and environmental catalysis.
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Vaccines have proven effective in protecting populations against COVID-19, including the recombinant COVID-19 vaccine (Sf9 cells), the first approved recombinant protein vaccine in China. In this positive-controlled trial with 85 adult participants (Sf9 cells group: n = 44; CoronaVac group: n = 41), we evaluated the safety, immunogenicity, and protective effectiveness of a heterologous boost with the Sf9 cells vaccine in adults who had been vaccinated with the inactivated vaccine, and found a post-booster adverse events rate of 20.45% in the Sf9 cells group and 31.71% in the CoronaVac group (p = 0.279), within 28 days after booster injection. Neither group reported any severe adverse events. Following the Sf9 cells vaccine booster, the geometric mean titer (GMT) of binding antibodies to the receptor-binding domain of prototype SARS-CoV-2 on day 28 post-booster was significantly higher than that induced by the CoronaVac vaccine booster (100,683.37 vs. 9,451.69, p < 0.001). In the Sf9 cells group, GMTs of neutralizing antibodies against pseudo SARS-CoV-2 viruses (prototype and diverse variants of concern [VOCs]) increased by 22.23-75.93 folds from baseline to day 28 post-booster, while the CoronaVac group showed increases of only 3.29-10.70 folds. Similarly, neutralizing antibodies against live SARS-CoV-2 viruses (prototype and diverse VOCs) increased by 68.18-192.67 folds on day 14 post-booster compared with the baseline level, significantly greater than the CoronaVac group (19.67-37.67 folds). A more robust Th1 cellular response was observed with the Sf9 cells booster on day 14 post-booster (mean IFN-γ+ spot-forming cells per 2 × 105 peripheral blood mononuclear cells: 26.66 vs. 13.59). Protective effectiveness against symptomatic COVID-19 was approximately twice as high in the Sf9 cells group compared to the CoronaVac group (68.18% vs. 36.59%, p = 0.004). Our study findings support the high protective effectiveness of heterologous boosting with the recombinant COVID-19 vaccine (Sf9 cells) against symptomatic COVID-19 of diverse SARS-CoV-2 variants of concern, while causing no apparent safety concerns.
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Vacinas contra COVID-19 , COVID-19 , Adulto , Animais , Humanos , COVID-19/prevenção & controle , Leucócitos Mononucleares , Células Sf9 , SARS-CoV-2 , Anticorpos Neutralizantes , Vacinas de Produtos InativadosRESUMO
The increase in the styrene content in styrene-butadiene rubber (SBR) can improve the abrasion performance and cutting resistance of rubber, which has received attention in the tire industry. The fatigue performance is the main evaluation index of rubber materials applied to tires. In this study, the effect of the styrene content and its interaction with carbon black (CB) on the dynamic fatigue performance and mechanism of SBR were investigated. The results indicated that the dynamic fatigue life of the rubber composite materials was prolonged with increasing styrene content; furthermore, it showed a trend of increasing and then decreasing with increasing CB content. At a certain CB content, styrene and CB displayed a synergistic effect on improving the dynamic fatigue life of the composite materials. The dynamic fatigue performance of SBR40/CB20 was the best. The expansion of the fatigue cracks followed the secondary cracking mechanism, which consumed a large amount of strain energy and slowed the development of the main crack. However, when the CB content exceeded 40 phr, the mechanism transformed to main crack self-propagation and the fatigue life decreased.
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Typically, SO2 unavoidably deactivates catalysts in most heterogeneous catalytic oxidations. However, for Pt-based catalysts, SO2 exhibits an extraordinary boosting effect in propane catalytic oxidation, but the promotive mechanism remains contentious. In this study, an in situ-formed tactful (Pt-S-O)-Ti structure was concluded to be a key factor for Pt/TiO2 catalysts with a substantial SO2 tolerance ability. The experiments and theoretical calculations confirm that the high degree of hybridization and orbital coupling between Pt 5d and S 3p orbitals enable more charge transfer from Pt to S species, thus forming the (Pt-S-O)-Ti structure with the oxygen atom dissociated from the chemisorbed O2 adsorbed on oxygen vacancies. The active oxygen atom in the (Pt-S-O)-Ti active structure is a robust site for C3H8 adsorption, leading to a better C3H8 combustion performance. This work can provide insights into the rational design of chemical bonds for high SO2 tolerance catalysts, thereby improving economic and environmental benefits.
Assuntos
Oxigênio , Titânio , Titânio/química , Oxirredução , Catálise , AdsorçãoRESUMO
The contamination of drinking water by microbes is a critical health concern, underscoring the need for safe, reliable, and efficient methods to treat pathogenic microorganisms. While most sterilization materials are available in powder form, this presents safety risks and challenges in recycling. Herein, this study reports the preparation of an innovative copper oxide supported silver monolithic nanoarray mesh with abundant oxygen vacancies (Ag/CuO-VO) by laser ablation. The instantaneous high temperature caused by laser ablation preserves the material's original structure while generating oxygen vacancies on the CuO surface. The Ag/CuO-VO mesh demonstrated a remarkable ability to inactivate over 99% of Escherichia coli (E. Coli) within 20 min. The oxygen vacancies in the Ag/CuO-VO enhance interactions between oxygen species and the Ag/CuO-VO, leading to the accumulation of large amounts of reactive oxygen species (ROS). The generated ROS effectively disrupt both layers of the bacterial cell wall - the peptidoglycan and the phospholipid - as confirmed by Fourier Transform Infrared (FTIR) spectroscopy, culminating in cell death. This research presents a monolithic material capable of inactivating pathogenic microorganisms efficiently, offering a significant advancement in water sterilization technology.
Assuntos
Escherichia coli , Terapia a Laser , Escherichia coli/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Oxigênio/metabolismo , Cobre/química , Prata/química , Bactérias/metabolismo , Antibacterianos/químicaRESUMO
BACKGROUND: Autotaxin (ATX) and lysophosphatidic acid (LPA) play an important role in pathogenesis of idiopathic pulmonary fibrosis (IPF). FTP-198 is an oral, novel and selective ATX inhibitor indicated for treating IPF. The study aimed to investigate the pharmacokinetics, pharmacodynamics, safety and tolerability of FTP-198 in healthy subjects. METHODS: A single-center, randomized, double-blind, placebo-controlled, single ascending-dose Phase I study was performed. Pharmacokinetics, pharmacodynamics, food effect on pharmacokinetics, elimination, safety and tolerability of FTP-198 were evaluated. RESULTS: A total of 30 subjects were enrolled and completed the study. After oral administration of single ascending-dose of 100 mg, 300 mg and 400 mg FTP-198 under fasted condition, FTP-198 was absorbed with median time to reach peak concentration (Tmax) of 1.75, 2.75 and 3.5 h, respectively and eliminated with mean elimination half-life (t1/2) of 8.77, 10.58 and 10.57 h, respectively. Peak concentration (Cmax), plasma area under concentration-time curve from time 0 to the last measurable concentration (AUC0-t) and to infinity (AUC0-∞) increased in dose-proportional manner for 100 mg to 400 mg FTP-198. Food intake slightly increased the Cmax, AUC0-t and AUC0-∞ and prolonged Tmax, but not affecting t1/2 of FTP-198 compared with fasted state. The pharmacodynamic biomarker plasma lysophosphatidic acid (LPA) 18:2 decreased significantly for 100 mg to 400 mg FTP-198, with inhibition rate from baseline reaching approximately 80% at 24 h post dosing, and higher dose of FTP-198 increased the time to maintain inhibitory plateau. FTP-198 was eliminated from the body almost with no unchanged drug excreted in urine and a small amount of unchanged drug detected in feces of human. Moreover, FTP-198 exhibited favorable safety and tolerability in healthy subjects. CONCLUSION: Pharmacokinetics, pharmacodynamics, safety and tolerability of FTP-198 support further subsequent clinical development of FTP -198 in IPF patients.
Assuntos
Fibrose Pulmonar Idiopática , Humanos , Voluntários Saudáveis , Área Sob a Curva , Administração Oral , Meia-Vida , Método Duplo-Cego , Fibrose Pulmonar Idiopática/tratamento farmacológico , Relação Dose-Resposta a DrogaRESUMO
Background: Pramipexole dihydrochloride extended-release tablet is a novel long-acting form of non-ergot dopamine agonist indicated as one of main therapeutic approaches for Parkinson's disease. However, pharmacokinetic properties of extended-release pramipexole in healthy Chinese subjects remain unclear. Methods: A single-center, randomized, open-label, two-period crossover, single-dose study was performed to investigate comparative pharmacokinetics and evaluate bioequivalence of 0.375 mg test (Yangtze River Pharmaceutical Group Co., Ltd.) and reference (Trade name: Sifrol®, Boehringer Ingelheim Pharma GmbH & Co. KG) formulations of pramipexole dihydrochloride extended-release tablets in healthy Chinese subjects under fasted and fed states. Results: A total of 56 subjects (28 in each dietary trial) were enrolled and randomized. After single dose of 0.375 mg test and reference formulations under fasted condition, main pharmacokinetics of pramipexole were as follows: peak concentration (Cmax) were 409.33±95.93 and 413.77±132.03 pg/mL; plasma area under concentration-time curve from time 0 to last measurable concentration (AUC0-t) were 8801.95±1966.83 and 8646.37±2600.49 h*pg/mL; AUC from time 0 to infinity (AUC0-∞) were 9469.03±1991.61 and 9082.95±2666.26 h*pg/mL; elimination half-life (t1/2) were 11.98±3.91 and 9.85±2.63 h; both time to reach Cmax (Tmax) were about 4.50 h, respectively, for test and reference formulations. The 90% confidence intervals of geometric mean ratios (test/reference) of Cmax, AUC0-t and AUC0-∞ under fasted and fed conditions were all within 80-125%. Following administration under fed condition, Cmax and Tmax for both test and reference formulations slightly increased and prolonged to 5.0 h, respectively, but AUC approximately remained unchanged compared with dosing under fasted condition. Test and reference formulations showed similar bioequivalence and favorable safety under fasted and fed states. Conclusion: Test and reference formulations of pramipexole dihydrochloride extended-release tablets (0.375 mg) showed similar bioequivalence and well safety and tolerability in healthy Chinese subjects under fasted and fed states, which supports further investigations of test formulation in patients with Parkinson's disease.
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Agonistas de Dopamina , População do Leste Asiático , Pramipexol , Equivalência Terapêutica , Humanos , Jejum , Doença de Parkinson/tratamento farmacológico , Pramipexol/farmacocinética , Estudos Cross-Over , Preparações de Ação Retardada/farmacocinética , Voluntários Saudáveis , Ingestão de Alimentos , Agonistas de Dopamina/farmacocinéticaRESUMO
Antibiotic resistance poses a growing risk to public health, requiring new tools to combat pathogenic bacteria. Contractile injection systems, including bacteriophage tails, pyocins, and bacterial type VI secretion systems, can efficiently penetrate cell envelopes and become potential antibacterial agents. Bacteriophage XM1 is a dsDNA virus belonging to the Myoviridae family and infecting Vibrio bacteria. The XM1 virion, made of 18 different proteins, consists of an icosahedral head and a contractile tail, terminated with a baseplate. Here, we report cryo-EM reconstructions of all components of the XM1 virion and describe the atomic structures of 14 XM1 proteins. The XM1 baseplate is composed of a central hub surrounded by six wedge modules to which twelve spikes are attached. The XM1 tail contains a fewer number of smaller proteins compared to other reported phage baseplates, depicting the minimum requirements for building an effective cell-envelope-penetrating machine. We describe the tail sheath structure in the pre-infection and post-infection states and its conformational changes during infection. In addition, we report, for the first time, the in situ structure of the phage neck region to near-atomic resolution. Based on these structures, we propose mechanisms of virus assembly and infection.
Assuntos
Bacteriófagos , Myoviridae , Myoviridae/genética , Bacteriófagos/genética , Antibacterianos , Membrana Celular , DNARESUMO
Catalytic ozone (O3 ) decomposition at high relative humidity (RH) remains a great challenge due to the catalysts poison and deactivation under high humidity. Here, we firstly elaborate the role of water activation and the corresponding mechanism of the promoted O3 decomposition over the three-dimensional monolithic molybdenum oxide/graphdiyne (MoO3 /GDY) catalyst. The O3 decomposition over MoO3 /GDY reaches up to 100 % under high humid condition (75 % RH) at room temperature, which is 4.0 times as high as that of dry conditions, significantly surpasses other carbon-based MoO3 materials(≤7.1 %). The sp-hybridized carbon in GDY donates electrons to MoO3 along the C-O-Mo bond, facilitating water activation to form hydroxyl species. As a result, hydroxyl species dissociated from water act as new active sites, promoting the adsorption of O3 and the generation of new intermediate species (hydroxyl â OH and superoxo â O2 - ), which significantly lowers the energy barriers of O3 decomposition (0.57â eV lower than dry conditions).
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We describe the confining instabilities of a proposed quantum spin liquid underlying the pseudogap metal state of the hole-doped cuprates. The spin liquid can be described by a SU(2) gauge theory of Nf = 2 massless Dirac fermions carrying fundamental gauge charges-this is the low-energy theory of a mean-field state of fermionic spinons moving on the square lattice with π-flux per plaquette in the â¤2 center of SU(2). This theory has an emergent SO(5)f global symmetry and is presumed to confine at low energies to the Néel state. At nonzero doping (or smaller Hubbard repulsion U at half-filling), we argue that confinement occurs via the Higgs condensation of bosonic chargons carrying fundamental SU(2) gauge charges also moving in π â¤2-flux. At half-filling, the low-energy theory of the Higgs sector has Nb = 2 relativistic bosons with a possible emergent SO(5)b global symmetry describing rotations between a d-wave superconductor, period-2 charge stripes, and the time-reversal breaking "d-density wave" state. We propose a conformal SU(2) gauge theory with Nf = 2 fundamental fermions, Nb = 2 fundamental bosons, and a SO(5)f×SO(5)b global symmetry, which describes a deconfined quantum critical point between a confining state which breaks SO(5)f and a confining state which breaks SO(5)b. The pattern of symmetry breaking within both SO(5)s is determined by terms likely irrelevant at the critical point, which can be chosen to obtain a transition between Néel order and d-wave superconductivity. A similar theory applies at nonzero doping and large U, with longer-range couplings of the chargons leading to charge order with longer periods.
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BACKGROUND: Inclisiran is a novel siRNA therapy that inhibits the synthesis of proprotein convertase subtilisin-kexin type 9 (PCSK9) by targeting the PCSK9 mRNA, consequently, decreases low-density lipoprotein cholesterol (LDL-C). OBJECTIVE: To assess the safety, PK and LDL-C lowering effects of inclisiran in the Chinese patients with elevated LDL-C despite treatment with maximally tolerated LDL-C lowering therapies. METHODS: Forty Chinese patients with hypercholesterolemia (LDL-C ≥100 mg/dL) who were on maximally tolerated statin were randomized to receive a single dose of either inclisiran sodium 100 or 300mg s.c. injection (each for 15 patients) or placebo (10 patients). Safety, pharmacokinetics and pharmacodynamics (i.e., PCSK9 and LDL-C levels) were evaluated for up to 90 days after the s.c. injection of study drug. RESULTS: Following single subcutaneous injections inclisiran sodium at 100 mg or 300 mg, inclisiran has a relative short elimination half-life (T1/2, 6.5 hours). Both plasma PCSK9 and serum LDL-C decreased rapidly and consistently, with the maximal reduction between Day 30 and Day 60; then the decreases of PCSK9 and LDL-C were generally maintained up to 56.4% and 49.6% of 100 mg, 74.9% and 58.3% of 300 mg, respectively, at day 90. All adverse events were mild or moderate in severity, and no discontinuations due to adverse events. There were no serious adverse events being reported. CONCLUSIONS: Inclisiran was generally safe and well tolerated. Single dose of both Inclisiran 100 and 300 mg significantly reduced PCSK9 and LDL-C levels in Chinese patients up to Day 90. The greatest reductions were observed with the 300 mg regimen of Inclisiran. TRIAL REGISTRATION: ClinicalTrials.gov: NCT04774003.
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Anticolesterolemiantes , Hipercolesterolemia , RNA Interferente Pequeno , Humanos , Anticolesterolemiantes/uso terapêutico , LDL-Colesterol , População do Leste Asiático , Hipercolesterolemia/tratamento farmacológico , Pró-Proteína Convertase 9/genética , RNA Interferente Pequeno/uso terapêuticoRESUMO
BACKGROUND: The prognostic value of cytokeratin 19 fragment (CYFRA 21 - 1) and Ki67 in advanced non-small cell lung cancer (NSCLC) patients with wild-type epidermal growth factor receptor (EGFR) remains to be explored. METHODS: In this study, 983 primary NSCLC patients from January 2016 to December 2019 were retrospectively reviewed. Finally, 117 advanced NSCLC patients with wild-type EGFR and 37 patients with EGFR mutation were included and prognostic value of CYFRA 21 - 1 and Ki67 were also identified. RESULTS: The patients age, smoking history and the Eastern Corporative Oncology Group (ECOG) performance scores were significantly different between CYFRA21-1 positive and negative groups (p < 0.05), while no significant differences were found in Ki67 high and low groups. The results of over survival (OS) demonstrated that patients with CYFRA21-1 positive had markedly shorter survival time than CYFRA21-1 negative (p < 0.001, For whole cohorts; p = 0.002, For wild-type EGFR). Besides, patients with wild-type EGFR also had shorter survival times than Ki67 high group. Moreover, In CYFRA 21 - 1 positive group, patients with Ki67 high had obviously shorter survival time compared to patients with Ki67 low (median: 24vs23.5 months; p = 0.048). However, Ki67 could not be used as an adverse risk factor for patients with EGFR mutation. Multivariate cox analysis showed that age (HR, 1.031; 95%CI, 1.003 ~ 1.006; p = 0.028), Histopathology (HR, 1.760; 95%CI,1.152 ~ 2.690; p = 0.009), CYFRA 21 - 1 (HR, 2.304; 95%CI,1.224 ~ 4.335; p = 0.01) and Ki67 (HR, 2.130; 95%CI,1.242 ~ 3.652; p = 0.006) served as independent prognostic risk factor for advanced NSCLC patients. CONCLUSIONS: Our finding indicated that CYFRA 21 - 1 was an independent prognostic factor for advanced NSCLC patients and Ki67 status could be a risk stratification marker for CYFRA 21 - 1 positive NSCLC patients with wild-type EGFR.
Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Queratina-19/genética , Prognóstico , Neoplasias Pulmonares/genética , Estudos Retrospectivos , Receptores ErbB/genética , Mutação , Biomarcadores Tumorais/genéticaRESUMO
BACKGROUND AND AIM: Severe acute pancreatitis (SAP) in patients progresses rapidly and can cause multiple organ failures associated with high mortality. We aimed to train a machine learning (ML) model and establish a nomogram that could identify SAP, early in the course of acute pancreatitis (AP). METHODS: In this retrospective study, 631 patients with AP were enrolled in the training cohort. For predicting SAP early, five supervised ML models were employed, such as random forest (RF), K-nearest neighbors (KNN), and naive Bayes (NB), which were evaluated by accuracy (ACC) and the areas under the receiver operating characteristic curve (AUC). The nomogram was established, and the predictive ability was assessed by the calibration curve and AUC. They were externally validated by an independent cohort of 109 patients with AP. RESULTS: In the training cohort, the AUC of RF, KNN, and NB models were 0.969, 0.954, and 0.951, respectively, while the AUC of the Bedside Index for Severity in Acute Pancreatitis (BISAP), Ranson and Glasgow scores were only 0.796, 0.847, and 0.837, respectively. In the validation cohort, the RF model also showed the highest AUC, which was 0.961. The AUC for the nomogram was 0.888 and 0.955 in the training and validation cohort, respectively. CONCLUSIONS: Our findings suggested that the RF model exhibited the best predictive performance, and the nomogram provided a visual scoring model for clinical practice. Our models may serve as practical tools for facilitating personalized treatment options and improving clinical outcomes through pre-treatment stratification of patients with AP.