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Rechargeable hydrogen gas batteries, driven by hydrogen evolution and oxidation reactions (HER/HOR), are emerging grid-scale energy storage technologies owing to their low cost and superb cycle life. However, compared with aqueous electrolytes, the HER/HOR activities in nonaqueous electrolytes have rarely been studied. Here, for the first time, we develop a nonaqueous proton electrolyte (NAPE) for a high-performance hydrogen gas-proton battery for all-climate energy storage applications. The advanced nonaqueous hydrogen gas-proton battery (NAHPB) assembled with a representative V2(PO4)3 cathode and H2 anode in a NAPE exhibits a high discharge capacity of 165 mAh g-1 at 1 C at room temperature. It also efficiently operates under all-climate conditions (from -30 to +70 °C) with an excellent electrochemical performance. Our findings offer a new direction for designing nonaqueous proton batteries in a wide temperature range.
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Stimuli-responsive nano-assemblies from amphiphilic macromolecules could undergo controlled structural transformations and generate diverse macroscopic phenomenon under stimuli. Due to the controllable responsiveness, they have been applied for broad material and biomedical applications, such as biologics delivery, sensing, imaging, and catalysis. Understanding the mechanisms of the assembly-disassembly processes and structural determinants behind the responsive properties is fundamentally important for designing the next generation of nano-assemblies with programmable responsiveness. In this review, we focus on structural determinants of assemblies from amphiphilic macromolecules and their macromolecular level alterations under stimuli, such as the disruption of hydrophilic-lipophilic balance (HLB), depolymerization, decrosslinking, and changes of molecular packing in assemblies, which eventually lead to a series of macroscopic phenomenon for practical purposes. Applications of stimuli-responsive nano-assemblies in delivery, sensing and imaging were also summarized based on their structural features. We expect this review could provide readers an overview of the structural considerations in the design and applications of nanoassemblies and incentivize more explorations in stimuli-responsive soft matters.
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Electronic cigarettes (e-cigarettes), as alternative nicotine delivery methods, has rapidly increased among youth and adults in recent years. However, cardiovascular safety is an important consideration regarding e-cigarettes usage. e-cigarette emissions, including nicotine, propylene glycol, flavorings, nitrosamine, and metals, might have adverse effects on cardiovascular health. A large body of epidemiological evidence has indicated that e-cigarettes are considered an independent risk factor for increased rates of cardiovascular disease occurrence and death. The incidence and mortality of various types of cardiovascular disease, such as cardiac arrhythmia, hypertension, acute coronary syndromes, and heart failure, have a modest growth in vapers (users of e-cigarettes). Although the underlying biological mechanisms have not been fully understood, studies have validated that oxidative stress, inflammation, endothelial dysfunction, atherosclerosis, hemodynamic effects, and platelet function play important roles in which e-cigarettes work in the human body. This minireview consolidates and discusses the epidemiological and biological links between e-cigarettes and various types of cardiovascular disease.
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Doenças Cardiovasculares , Sistemas Eletrônicos de Liberação de Nicotina , Humanos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Vaping/efeitos adversos , Vaping/epidemiologia , Animais , Nicotina/efeitos adversos , Nicotina/administração & dosagemRESUMO
Although chemical methods for the selective derivatization of amino acid (AA) side chains in peptides and proteins are available, selective N-terminal labeling is challenging, especially for glycine, which has no side chain at the α-carbon position. We report here a double activation at glycine's α-methylene group that allows this AA to be differentiated from the other 19 AAs. A condensation reaction of dibenzoylmethane with glycine results in the formation of an imine, and subsequent tautomerization is followed by intramolecular cyclization, leading to the formation of a fluorescent pyrrole ring. Additionally, the approach exhibits compatibility with AAs possessing reactive side chains. Further, the method allows for selective pull-down assays of N-terminal glycine peptides from mixtures without prior knowledge of the N-terminal peptide distribution.
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Corantes Fluorescentes , Glicina , Peptídeos , Glicina/química , Corantes Fluorescentes/química , Peptídeos/química , Estrutura MolecularRESUMO
The majority of the immune cell population in the tumor microenvironment (TME) consists of tumor-associated macrophages (TAM), which are the main players in coordinating tumor-associated inflammation. TAM has a high plasticity and is divided into two main phenotypes, pro-inflammatory M1 type and anti-inflammatory M2 type, with tumor-suppressive and tumor-promoting functions, respectively. Considering the beneficial effects of M1 macrophages for anti-tumor and the high plasticity of macrophages, the conversion of M2 TAM to M1 TAM is feasible and positive for tumor treatment. This study sought to evaluate whether the glycopeptide derived from simulated digested Codonopsis pilosula extracts could regulate the polarization of M2-like TAM toward the M1 phenotype and the potential regulatory mechanisms. The results showed that after glycopeptide dCP1 treatment, the mRNA relative expression levels of some M2 phenotype marker genes in M2-like TAM in simulated TME were reduced, and the relative expression levels of M1 phenotype marker genes and inflammatory factor genes were increased. Analysis of RNA-Seq of M2-like TAM after glycopeptide dCP1 intervention showed that the gene sets such as glycolysis, which is associated with macrophage polarization in the M1 phenotype, were significantly up-regulated, whereas those of gene sets such as IL-6-JAK-STAT3 pathway, which is associated with polarization in the M2 phenotype, were significantly down-regulated. Moreover, PCA analysis and Pearson's correlation also indicated that M2-like TAM polarized toward the M1 phenotype at the transcriptional level after treatment with the glycopeptide dCP1. Lipid metabolomics was used to further explore the efficacy of the glycopeptide dCP1 in regulating the polarization of M2-like TAM to the M1 phenotype. It was found that the lipid metabolite profiles in dCP1-treated M2-like TAM showed M1 phenotype macrophage lipid metabolism profiles compared with blank M2-like TAM. Analysis of the key differential lipid metabolites revealed that the interconversion between phosphatidylcholine (PC) and diacylglycerol (DG) metabolites may be the central reaction of the glycopeptide dCP1 in regulating the conversion of M2-like TAM to the M1 phenotype. The above results suggest that the glycopeptide dCP1 has the efficacy to regulate the polarization of M2-like TAM to M1 phenotype in simulated TME.
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Codonopsis , Fenótipo , Macrófagos Associados a Tumor , Animais , Humanos , Camundongos , Glicopeptídeos/metabolismo , Glicopeptídeos/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Neoplasias/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias/imunologia , Microambiente Tumoral/efeitos dos fármacos , Macrófagos Associados a Tumor/metabolismo , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/efeitos dos fármacosRESUMO
In this study, the dual strategy of 1-butyl-3-vinylimidazolium bromide ionic liquid (IL) grafting and carbon nanotubes (CNTs) nanocomposition was applied to modify poly(vinylidene fluoride) (PVDF)-based membranes. The highly hydrophilic/oleophobic and fouling-resistant PVDF-g-IL/CNTs membranes with excellent separation efficiency were obtained by the nonsolvent-induced phase separation method with ethanol-water mixed solution as the coagulation bath. The grafted IL not only generated hydrophilic groups on PVDF chains but also acted together with the CNTs to induce the formation of hydrophilic ß-crystalline phase of PVDF, which significantly improved the hydrophilicity and pore structure of the modified PVDF membranes. As a result, the pure water flux of the optimal membrane increased up to 294.2 L m-2 h-1, which was 5.2 times greater than that of the pure PVDF membrane. Simultaneously, the electrostatic interaction of the positive IL and the integration of CNTs enhanced adsorption sites of the membranes, producing exceptional retention and adsorption of dye wastewater and oil-water emulsion. This study presents a straightforward and efficient approach for fabricating PVDF separation membranes, which have potential applications in the purification of various polluted wastewater.
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Pure SnO2 and 1 at.% PdO-SnO2 materials were prepared using a simple hydrothermal method. The micromorphology and element valence state of the material were characterized using XRD, SEM, TEM, and XPS methods. The SEM results showed that the prepared material had a two-dimensional nanosheet morphology, and the formation of PdO and SnO2 heterostructures was validated through TEM. Due to the influence of the heterojunction, in the XPS test, the energy spectrum peaks of Sn and O in PdO-SnO2 were shifted by 0.2 eV compared with SnO2. The PdO-SnO2 sensor showed improved ethanol sensing performance compared to the pure SnO2 sensor, since it benefited from the large specific surface area of the nanosheet structure, the modulation effect of the PdO-SnO2 heterojunction on resistance, and the catalyst effect of PdO on the adsorption of oxygen. A DFT calculation study of the ethanol adsorption characteristics of the PdO-SnO2 surface was conducted to provide a detailed explanation of the gas-sensing mechanism. PdO was found to improve the reducibility of ethanol, enhance the adsorption of ethanol's methyl group, and increase the number of adsorption sites. A synergistic effect based on the continuous adsorption sites was also deduced.
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Ongoing research has revealed that the existence of cancer stem cells (CSCs) is one of the biggest obstacles in the current cancer therapy. CSCs make an influential function in tumor progression, recurrence and chemoresistance due to their typical stemness characteristics. CSCs are preferentially distributed in niches, and those niche sites exhibit characteristics typical of the tumor microenvironment (TME). The complex interactions between CSCs and TME illustrate these synergistic effects. The phenotypic heterogeneity within CSCs and the spatial interactions with the surrounding tumor microenvironment led to increased therapeutic challenges. CSCs interact with immune cells to protect themselves against immune clearance by exploiting the immunosuppressive function of multiple immune checkpoint molecules. CSCs also can protect themselves against immune surveillance by excreting extracellular vesicles (EVs), growth factors, metabolites and cytokines into the TME, thereby modulating the composition of the TME. Therefore, these interactions are also being considered for the therapeutic development of anti-tumor agents. We discuss here the immune molecular mechanisms of CSCs and comprehensively review the interplay between CSCs and the immune system. Thus, studies on this topic seem to provide novel ideas for reinvigorating therapeutic approaches to cancer.
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Antineoplásicos , Neoplasias , Humanos , Microambiente Tumoral , Neoplasias/patologia , Antineoplásicos/farmacologia , Citocinas/metabolismo , Células-Tronco Neoplásicas/metabolismoRESUMO
Integrins are transmembrane receptors that possess distinct ligand-binding specificities in the extracellular domain and signaling properties in the cytoplasmic domain. While most integrins have a short cytoplasmic tail, integrin ß4 has a long cytoplasmic tail that can indirectly interact with the actin cytoskeleton. Additionally, 'inside-out' signals can induce integrins to adopt a high-affinity extended conformation for their appropriate ligands. These properties enable integrins to transmit bidirectional cellular signals, making it a critical regulator of various biological processes.Integrin expression and function are tightly linked to various aspects of tumor progression, including initiation, angiogenesis, cell motility, invasion, and metastasis. Certain integrins have been shown to drive tumorigenesis or amplify oncogenic signals by interacting with corresponding receptors, while others have marginal or even suppressive effects. Additionally, different α/ß subtypes of integrins can exhibit opposite effects. Integrin-mediated signaling pathways including Ras- and Rho-GTPase, TGFß, Hippo, Wnt, Notch, and sonic hedgehog (Shh) are involved in various stages of tumorigenesis. Therefore, understanding the complex regulatory mechanisms and molecular specificities of integrins are crucial to delaying cancer progression and suppressing tumorigenesis. Furthermore, the development of integrin-based therapeutics for cancer are of great importance.This review provides an overview of integrin-dependent bidirectional signaling mechanisms in cancer that can either support or oppose tumorigenesis by interacting with various signaling pathways. Finally, we focus on the future opportunities for emergent therapeutics based on integrin agonists. Video Abstract.
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Proteínas Hedgehog , Neoplasias , Humanos , Integrinas/metabolismo , Transdução de Sinais , CarcinogêneseRESUMO
In the present work, self-cleaning membranes of ionic liquid-grafted poly(vinylidene fluoride) (PVDF) polydopamine-coated TiO2 were prepared through a nonsolvent-induced phase separation method. PDA facilitates the uniform dispersion of TiO2 nanoparticles in PVDF substrates; meanwhile, TiO2@PDA core-shell particles and the hydrophilic IL improve the hydrophilicity of PVDF membranes and contribute to the increased average pore size and porosity, significantly improving the pure water permeation flux and dye wastewater flux (the water flux increased to 385.9 Lm-2 h-1). In addition, the combined effect of the positively charged IL and the strongly viscous PDA shell layer enhanced the retention and adsorption of dyes so that the retention and adsorption rates of both anionic and cationic dyes were close to 100%. Notably, the hydrophilic PDA allowed more TiO2 to migrate to the membrane surface during the phase transition; on the other hand, dopamine could promote photodegradation. Therefore, the combined two factors for TiO2@PDA were beneficial to the ultraviolet-catalytic (UV-catalytic) degradation of dyes on the surface of the membrane, leading to >80% degradation rates of various dyes. Thus, the high-efficiency and easy-to-operate wastewater treatment technology provides attractive potential for dye removal and resolution of membrane contamination.
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BACKGROUND: Despite advances in perioperative care, elective major vascular surgical procedures still carry a significant risk of morbidity and mortality. Remote ischaemic preconditioning (RIPC) is the temporary blocking of blood flow to vascular beds remote from those targeted by surgery. It has the potential to provide local tissue protection from further prolonged periods of ischaemia. However, the efficacy and safety of RIPC in people undergoing major vascular surgery remain unknown. This is an update of a review published in 2011. OBJECTIVES: To assess the benefits and harms of RIPC versus no RIPC in people undergoing elective major vascular and endovascular surgery. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, and CINAHL databases and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov to 1 April 2022. SELECTION CRITERIA: We included all randomised controlled trials that evaluated the role of RIPC in reducing perioperative mortality and morbidities in people undergoing elective major vascular or endovascular surgery. DATA COLLECTION AND ANALYSIS: We collected data on the characteristics of the trial, methodological quality, and the remote ischaemic preconditioning stimulus used. Our primary outcome was perioperative mortality, and secondary outcomes included myocardial infarction, renal impairment, stroke, hospital stay, limb loss, and operating time or total anaesthetic time. We analysed the data using random-effects models. For each outcome, we calculated the risk ratio (RR) or mean difference (MD) with a 95% confidence interval (CI) based on an intention-to-treat analysis. In addition, we used GRADE to assess the certainty of the evidence for each outcome. MAIN RESULTS: We included 14 trials which randomised a total of 1295 participants (age range: 64.5 to 76 years; 84% male; study periods ranged from 2003 to 2019). In general, the included studies were at low to unclear risk of bias for most risk of bias domains. The certainty of evidence of main outcomes was moderate due to imprecision of results, moderate heterogeneity, or possible publication bias. We found that RIPC made no clear difference in perioperative mortality compared with no RIPC (RR 1.41, 95% CI 0.59 to 3.40; I2 = 0%; 10 studies, 965 participants; moderate-certainty evidence). Similarly, we found no clear difference between the two groups for myocardial infarction (RR 0.82, 95% CI 0.49 to 1.40; I2 = 7%; 11 studies, 1001 participants; moderate-certainty evidence), renal impairment (RR 1.07, 95% CI 0.62 to 1.86; I2 = 40%; 12 studies, 1054 participants; moderate-certainty evidence), stroke (RR 0.33, 95% CI 0.04 to 3.15; I2 = 0%; 4 studies, 392 participants; moderate-certainty evidence), limb loss (RR 0.74, 95% CI 0.05 to 10.61; I2 = 32%; 3 studies, 322 participants; low-certainty evidence), hospital stay (MD -0.94 day, 95% CI -1.95 to 0.07; I2 = 17%; 7 studies, 569 participants; moderate-certainty evidence), and operating time or total anaesthetic time (MD 5.76 minutes, 95% CI -3.25 to 14.76; I2 = 44%; 10 studies, 803 participants; moderate-certainty evidence). AUTHORS' CONCLUSIONS: Overall, compared with no RIPC, RIPC probably leads to little or no difference in perioperative mortality, myocardial infarction, renal impairment, stroke, hospital stay, and operating time, and may lead to little or no difference in limb loss in people undergoing elective major vascular and endovascular surgery. Adequately powered and designed randomised studies are needed, focusing in particular on the clinical endpoints and patient-centred outcomes.
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Procedimentos Endovasculares , Precondicionamento Isquêmico , Procedimentos Cirúrgicos Vasculares , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Isquemia , Precondicionamento Isquêmico/métodos , Infarto do Miocárdio/etiologia , Acidente Vascular Cerebral/etiologia , Procedimentos Cirúrgicos Vasculares/efeitos adversos , Procedimentos Cirúrgicos Vasculares/métodosRESUMO
Reporting the activity of a specific viral protease remains an acute need for rapid point-of-care detection strategies that can distinguish active infection from a resolved infection. In this work, we present a simple colorimetric approach for reporting the activity of a specific viral protease through direct color conversion on a cotton swab, which has the potential to be extended to detect the corresponding virus. We use SARS-CoV-2 viral protease as a proof-of-concept model system. We use 4-aminomalachite green (4-AMG) as the base chromophore structure to design a CoV2-AMG reporter, which is selective toward the SARS-CoV-2 Mpro but does not produce any observable color change in the presence of other viral proteases. The color change is observable by the naked eye, as well as smartphone imaging, which affords a lower limit of detection. The simplicity and generalizability of the method could be instrumental in combating future viral outbreaks.
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COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Colorimetria/métodos , Humanos , Peptídeo Hidrolases , Proteases ViraisRESUMO
This study aims to analyze the outcome indicators of randomized controlled trial(RCT) on traditional Chinese medicine(TCM) intervention of sepsis-induced myocardial injury(SIMI) in recent five years, which is expected to lay a basis for the construction of core outcome set(COS) for this disease treated by TCM. To be specific, RCT on the treatment of SIMI with TCM was retrieved from 4 Chinese databases, 3 English databases, and 2 clinical trial protocol registries. The quality of the included studies was evaluated with Cochrane risk-of-bias(ROB) tool, and the outcome indicators were analyzed. Finally, 42 RCTs were included, of which 2 were clinical trial registration schemes. The study found that 42 RCTs had a high risk of bias, and reported a total of 86 indicators in "clinical effective rate, disease severity, TCM syndrome score, inflammation, myocardium, cardiac structure and hemodynamics, electrocardiogram, immunology, metabolism and liver and kidney function, and safety". Outcome indicators on myocardium had the highest emergence frequency, followed by indicators on the cardiac structure and hemodynamics. A total of 8 RCTs reported TCM syndrome scores. Further analysis suggested the following problems in the selection of outcome indicators in the RCTs on TCM intervention of SIMI: no classification of primary and secondary indicators, disregard of endpoint indicators, irrational selection of alternative indicators, neglection of TCM characteristics, no assessment of patients' immune status, and no emphasis on economic indicators and safety indicators. Therefore, according to the recommendations of the core outcome measures in effectiveness trials(COMET) working group, a COS for TCM intervention of TCM for SIMI should be developed, so as to facilitate clinical researchers to select appropriate outcome indicators, the combination of conclusions of similar clinical studies, and the promotion of TCM interventions.
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Medicamentos de Ervas Chinesas , Sepse , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Medicina Tradicional Chinesa , Ensaios Clínicos Controlados Aleatórios como Assunto , Sepse/complicações , Sepse/tratamento farmacológico , Resultado do TratamentoRESUMO
A new multicomponent reaction involving 2-hydroxybenzaldehyde, amine, and 2-mercaptobenzaldehyde (HAM reaction) has been developed and applied to multicomponent polymerization and controlled radical polymerization for the construction of random and block copolymers. This chemistry features mild reaction conditions, high yield, simple isolation, and water as the only byproduct. With the advantages of the distinct nucleophilicity of thiol and hydroxyl groups, the chemistry could be used for stepwise labeling and modifications on primary amines. The Janus chemical joint formed from this reaction exhibits degradability in buffers and generates the corresponding starting reagents, allowing amine release. Interestingly, the chemical joint exhibits thermally activated reversibility with water as the catalyst. This multicomponent dynamic covalent feature has been applied to the metamorphosis of random and block copolymers, generating polymers with diverse architectures. This chemistry is expected to be broadly applicable to synthetic polymer chemistry and materials science.
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It is widely accepted that redox reprogramming participates in malignant transformation of lung adenocarcinoma (LUAD). However, the source of excessive reactive oxygen species (ROS) and the downstream signaling regulatory mechanism are complicated and unintelligible. In the current study, we newly identified the aquaporin 3 (AQP3) as a LUAD oncogenic factor with capacity to transport exogenous hydrogen peroxide (H2 O2 ) and increase intracellular ROS levels. Subsequently, we demonstrated that AQP3 was necessary for the facilitated diffusion of exogenous H2 O2 in LUAD cells and that the AQP3-dependent transport of H2 O2 accelerated cell growth and inhibited rapamycin-induced autophagy. Mechanistically, AQP3-mediated H2 O2 uptake increased intracellular ROS levels to inactivate PTEN and activate the AKT/mTOR pathway to subsequently inhibit autophagy and promote proliferation in LUAD cells. Finally, we suggested that AQP3 depletion retarded subcutaneous tumorigenesis in vivo and simultaneously decreased ROS levels and promoted autophagy. These findings underscore the importance of AQP3-induced oxidative stress in malignant transformation and suggest a therapeutic target for LUAD.
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Adenocarcinoma de Pulmão/patologia , Aquaporina 3/genética , Aquaporina 3/metabolismo , Peróxido de Hidrogênio/metabolismo , Neoplasias Pulmonares/patologia , PTEN Fosfo-Hidrolase/metabolismo , Células A549 , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Animais , Autofagia , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Transplante de Neoplasias , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Sirolimo/farmacologiaRESUMO
BACKGROUND: Lung cancer is highly prevalent in Chinese population. The association of operative approach with economic burden in these patients remains unknown. OBJECTIVES: This institution-level cohort study aimed to compare the cost-related clinical outcomes and health care costs among patients undergoing video-assisted thoracoscopic surgery (VATS) and open lobectomy, and to investigate the factors associated with the costs. METHODS: This retrospective cohort study included patients who underwent VATS or open lobectomy in a provincial referral cancer center in China in 2018. Propensity score matching (PSM) method was applied to balance the baseline characteristics in VATS lobectomy and open lobectomy group. Clinical effectiveness measures included post-operative blood transfusion, lung infection, and length of stay (LOS). Hospitalization costs were extracted from hospital information system to assess economic burden. Multivariable generalized linear model (GLM) with gamma probability distribution and log-link was used to analyze the factors associated with total costs. RESULTS: After PSM, 376 patients were selected in the analytic sample. Compared to open lobectomy group, the VATS lobectomy group had a lower blood transfusion rate (2.13% vs. 3.19%, P = 0.75), lower lung infection rate (21.28% vs. 39.89%, P < 0.001) and shorter post-operative LOS (9.4 ± 3.22 days vs. 10.86 ± 4.69 days, P < 0.001). Total hospitalization costs of VATS lobectomy group and open lobectomy were similar: Renminbi (RMB) 84398.03 ± 13616.13, RMB 81,964.92 ± 16748.11, respectively (P = 0.12). Total non-surgery costs were significantly lower in the VATS lobectomy group than in the open lobectomy group: RMB 41948.40 ± 7747.54 vs. RMB 45752.36 ± 10346.42 (P < 0.001). VATS approach, lung infection, longer post-operative length of stay, health insurance coverage, and lung cancer diagnosis were associated with higher total hospitalization costs (P < 0.05). CONCLUSIONS: VATS lobectomy has a lower lung infection rate, and shorter post-operative LOS than open lobectomy. Future studies are needed to investigate other aspects of clinical effectiveness and the economic burden from a societal perspective.
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Mitochondria are therapeutic targets in many diseases including cancer, metabolic disorders, and neurodegenerative diseases. Therefore, strategies to deliver therapeutics of interest to mitochondria are important for therapeutic development. As delocalized lipophilic cations (DLCs) preferentially accumulate in mitochondria, DLC-conjugation has been utilized to facilitate therapeutic delivery systems with mitochondrial targeting capability. Here we report that upon DLC-conjugation, anionic polymers exhibit significantly improved mitochondrial targeting when compared to cationic polymers and charge-neutral polymers. Considering that the cell membrane generally bears a net negative charge, the observed phenomenon is unexpected. Notably, the DLC-conjugated anionic polymers circumvent endosomal entrapment. The rapid mitochondrial accumulation of DLC-conjugated anionic polymers is likely a membrane-potential-driven process, along with the involvement of the mitochondrial pyruvate carrier. Moreover, the structural variations on the side chain of DLC-conjugated anionic polymers do not compromise the overall mitochondrial targeting capability, widely extending the applicability of anionic macromolecules in therapeutic delivery systems.
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Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Mitocôndrias/metabolismo , Polímeros/química , Polímeros/metabolismo , Células HeLa , Humanos , Cinética , Potencial da Membrana MitocondrialRESUMO
The interaction mechanism between external laser and Si avalanche photodiodes (Si-APDs) in practical circuits and the law of temperature increase are vital for the laser protection of Si-APDs. This study establishes the heating model of Si-APDs in an external circuit irradiated by a millisecond-pulse laser. The law of surface temperature increase in Si-APDs is determined via simulation and experiment. Results show that both laser energy density and external capacitance significantly affect the temperature increase. The theoretical simulation and experimental results are consistent, thereby validating the theoretical model.
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BACKGROUND: Blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI) and diffusion tensor imaging (DTI) are useful methods for investigating the morphology and function of the kidneys, including revealing unilateral renal damage. Nevertheless, these techniques have not yet been applied for bilateral renal function. The aim of this study was to investigate whether the combination of DTI and BOLD could be used to examine different degrees of contrast-induced acute kidney injury (CI-AKI) in bilateral kidneys compared to standard methods such as serum creatinine (SCr) detection. METHODS: Forty-Two New Zealand white rabbits were divided into two groups: the experimental group and the control group. Physiological saline and iodine contrast agent (iohexol, 1.0 g iodine/kg, 1.0 ml/sec) were injected via the right renal artery. DTI and BOLD-MR data were acquired longitudinally at the baseline and 1, 24, 48, and 72 h after high-pressure syringe injection to measure the apparent diffusion coefficient (ADC), fractional anisotropy (FA) and relative transverse relaxation rate (R2*). After the MR scan at each time point, three rabbits in each group were sacrificed, and changes in SCr and hypoxia-inducible factor-1α (HIF-1α) were analyzed using histopathology and immunochemistry. RESULTS: Twenty-four hours after iohexol administration, the values of ADC and FA decreased significantly (P < 0.05), while R2* values increased (P < 0.05) in the renal cortex (CO), outer medulla (OM) and inner medulla (IM). Besides, significant negative correlations were observed among ADC, FA, and R2* in CO, OM, and IM (all P < 0.001, r = - 0.654-0.828). CONCLUSIONS: DTI and BOLD can simultaneously and non-invasively assess different degrees of CI-AKI in bilateral kidneys.
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Injúria Renal Aguda/diagnóstico por imagem , Injúria Renal Aguda/fisiopatologia , Imagem de Tensor de Difusão , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/patologia , Animais , Anisotropia , Nitrogênio da Ureia Sanguínea , Meios de Contraste , Creatinina/sangue , Cistatina C/sangue , Difusão , Células Epiteliais/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Iohexol , Córtex Renal/diagnóstico por imagem , Medula Renal/diagnóstico por imagem , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Masculino , Oxigênio/sangue , CoelhosRESUMO
BACKGROUND: Moderate autophagy plays a positive role in the prevention of atherosclerosis. Aberrant promoter methylation of autophagic genes can affect autophagy. Shen-Yuan-Dan Capsule (SYDC), a traditional Chinese medicine, can prevent atherosclerosis in high-fat-fed mice. However, its precise mechanism remains unclear. This study investigated the mechanism of SYDC in ameliorating atherosclerosis in a mice model. METHODS: After 6 weeks of a high-fat diet, apolipoprotein E knockout (apoE-/-) mice were randomly grouped into control, Lipitor, and SYDC groups (n = 10). The mice were intragastrically administered with the respective drugs for 6 weeks. The expressions of Beclin1 and Atg5-Atg12 complex in atherosclerotic plaques of the mice were measured. The levels of 5-mC and DNA methyltransferase 1 (DNMT1) in the plasma of the mice were determined. The average methylation rate of CpG islands in the promoter region of autophagy-related protein (Atg13) and the mRNA expression of Atg13 in the aortas of the mice were determined. RESULTS: SYDC up-regulated the expressions of Atg5-Atg12 complex and Beclin-1 in atherosclerotic plaques (p < 0.01). Moreover, SYDC decreased the 5-mC and DNMT1 levels in plasma and atherosclerotic plaques of the mice (p < 0.01), and also decreased the average methylation rate of CpG islands in the promoter region of Atg13 and increased the mRNA levels of Atg13 in the aortas of atherosclerotic mice (p < 0.01). CONCLUSIONS: SYDC attenuates atherosclerosis by promoting autophagy, probably through regulating genomic DNA methylation and Atg13 promoter demethylation.