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1.
N Engl J Med ; 388(26): 2411-2421, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37222476

RESUMO

BACKGROUND: The effect of early as compared with later initiation of direct oral anticoagulants (DOACs) in persons with atrial fibrillation who have had an acute ischemic stroke is unclear. METHODS: We performed an investigator-initiated, open-label trial at 103 sites in 15 countries. Participants were randomly assigned in a 1:1 ratio to early anticoagulation (within 48 hours after a minor or moderate stroke or on day 6 or 7 after a major stroke) or later anticoagulation (day 3 or 4 after a minor stroke, day 6 or 7 after a moderate stroke, or day 12, 13, or 14 after a major stroke). Assessors were unaware of the trial-group assignments. The primary outcome was a composite of recurrent ischemic stroke, systemic embolism, major extracranial bleeding, symptomatic intracranial hemorrhage, or vascular death within 30 days after randomization. Secondary outcomes included the components of the composite primary outcome at 30 and 90 days. RESULTS: Of 2013 participants (37% with minor stroke, 40% with moderate stroke, and 23% with major stroke), 1006 were assigned to early anticoagulation and 1007 to later anticoagulation. A primary-outcome event occurred in 29 participants (2.9%) in the early-treatment group and 41 participants (4.1%) in the later-treatment group (risk difference, -1.18 percentage points; 95% confidence interval [CI], -2.84 to 0.47) by 30 days. Recurrent ischemic stroke occurred in 14 participants (1.4%) in the early-treatment group and 25 participants (2.5%) in the later-treatment group (odds ratio, 0.57; 95% CI, 0.29 to 1.07) by 30 days and in 18 participants (1.9%) and 30 participants (3.1%), respectively, by 90 days (odds ratio, 0.60; 95% CI, 0.33 to 1.06). Symptomatic intracranial hemorrhage occurred in 2 participants (0.2%) in both groups by 30 days. CONCLUSIONS: In this trial, the incidence of recurrent ischemic stroke, systemic embolism, major extracranial bleeding, symptomatic intracranial hemorrhage, or vascular death at 30 days was estimated to range from 2.8 percentage points lower to 0.5 percentage points higher (based on the 95% confidence interval) with early than with later use of DOACs. (Funded by the Swiss National Science Foundation and others; ELAN ClinicalTrials.gov number, NCT03148457.).


Assuntos
Fibrilação Atrial , Inibidores do Fator Xa , AVC Isquêmico , Humanos , Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Embolia/etiologia , Embolia/prevenção & controle , Hemorragia/induzido quimicamente , Hemorragias Intracranianas/induzido quimicamente , AVC Isquêmico/etiologia , AVC Isquêmico/prevenção & controle , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Resultado do Tratamento , Fatores de Tempo , Inibidores do Fator Xa/administração & dosagem , Inibidores do Fator Xa/efeitos adversos , Inibidores do Fator Xa/uso terapêutico , Recidiva
2.
Immunity ; 44(2): 422-37, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26885862

RESUMO

Dendritic cells (DCs) orchestrate complex membrane trafficking through an interconnected transportation network linked together by Rab GTPases. Through a tandem affinity purification strategy and mass spectrometry, we depicted an interactomic landscape of major members of the mammalian Rab GTPase family. When complemented with imaging tools, this proteomic analysis provided a global view of intracellular membrane organization. Driven by this analysis, we investigated dynamic changes to the Rab32 subnetwork in DCs induced by L. monocytogenes infection and uncovered an essential role of this subnetwork in controlling the intracellular proliferation of L. monocytogenes. Mechanistically, Rab32 formed a persistent complex with two interacting proteins, PHB and PHB2, to encompass bacteria both during early phagosome formation and after L. monocytogenes escaped the original containment vacuole. Collectively, we have provided a functional compartmentalization overview and an organizational framework of intracellular Rab-mediated vesicle trafficking that can serve as a resource for future investigations.


Assuntos
Células Dendríticas/imunologia , Listeria monocytogenes/imunologia , Listeriose/imunologia , Complexos Multiproteicos/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Aciltransferases/metabolismo , Animais , Anti-Infecciosos/uso terapêutico , Linhagem Celular , Biologia Computacional , Contenção de Riscos Biológicos , Células Dendríticas/microbiologia , Listeria monocytogenes/crescimento & desenvolvimento , Listeriose/tratamento farmacológico , Camundongos , Proibitinas , Transporte Proteico , Proteínas Repressoras/metabolismo , Vacúolos/metabolismo
3.
J Am Chem Soc ; 146(9): 5940-5951, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38386410

RESUMO

Solid polymer electrolytes (SPEs) are one of the most practical candidates for solid-state batteries owing to their high flexibility and low production cost, but their application is limited by low Li+ conductivity and a narrow electrochemical window. To improve performance, it is necessary to reveal the structure-property relationship of SPEs. Here, 23 fluorinated linear polyesters were prepared by editing the coordination units, flexible linkage segments, and interface passivating groups. Besides the traditionally demonstrated coordinating capability and flexibility of polymer chains, the molecular asymmetry and resulting interchain aggregation are observed critical for Li+ conductivity. By tailoring the molecular asymmetry and coordination ability of polyesters, the Li+ conductivity can be raised by 10 times. Among these polyesters, solvent-free poly(pentanediol adipate) delivers the highest room-temperature Li+ conductivity of 0.59 × 10-4 S cm-1. The chelating coordination of oxalate and Li+ leads to an electron delocalization of alkoxy oxygen, enhancing the antioxidation capability of SPEs. To lower the cost, high-value LiTFSI in SPEs is recycled at 90%, and polyesters can be regenerated at 86%. This work elucidates the structure-property relationship of polyester-based SPEs, displays the design principles of SPEs, and provides a way for the development of sustainable solid-state batteries.

4.
Langmuir ; 40(22): 11470-11480, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38768447

RESUMO

The inclusion of sacrificial hydrogen bonds is crucial for advancing high-performance rubber materials. However, the molecular mechanisms governing the impact of these bonds on material properties remain unclear, hindering progress in advanced rubber material research. This study employed all-atom molecular dynamics simulations to thoroughly investigate how hydrogen bonds affect the structure, dynamics, mechanics, and linear viscoelasticity of rubber materials. As the modified repeating unit ratio (ß) increased, both interchain and intrachain hydrogen bond content rose, with interchain bonds playing a predominant role. This physical cross-linking network formed through interchain hydrogen bonds restricts molecular chain movement and relaxation and raises the glass transition temperature of rubber. Within a certain content of hydrogen bonds, the mechanical strength increases with increasing ß. However, further increasing ß leads to a subsequent decrease in the mechanical performance. Optimal mechanical properties were observed at ß = 6%. On the other hand, a higher ß value yields an elevated stress relaxation modulus and an extended stress relaxation plateau, signifying a more complex hydrogen-bond cross-linking network. Additionally, higher ß increases the storage modulus, loss modulus, and complex viscosity while reducing the loss factor. In summary, this study successfully established the relationship between the structure and properties of natural rubber containing hydrogen bonds, providing a scientific foundation for the design of high-performance rubber materials.

5.
Langmuir ; 40(14): 7769-7780, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38551319

RESUMO

Polymer vitrimer is a novel material that contains dynamic covalent bonds (DCBs) allowing it to combine the desirable characteristics of both thermoplastics and thermosets. Similar to the traditional polymer nanocomposites, introducing nanoparticles into polymer vitrimer is also an effective strategy to further enhance its properties. However, a comprehensive understanding of matrix and interfacial bond exchange reactions (BERs) to tailor the properties of polymer vitrimer nanocomposites (PVNs) is still lacking. Herein, we utilized coarse-grained molecular dynamics simulations to investigate model PVNs in which there are two different kinds of DCBs in the vitrimer matrix and at the interface. Our results show that the normalized bond autocorrelation function (Csw) confirms the independence of BERs in the vitrimer matrix and in the interface. By varying the bond swap energy barrier (ΔEsw) in the matrix ΔEswmat or in the interface ΔEswint, or in both ΔEswall, a maximum mechanical property is observed at the moderate value of ΔEswmat, ΔEswint, orΔEswall. Meanwhile, the effect of ΔEsw on the stress relaxation and the bond orientation as a function of the time under a fixed strain is well probed, which both decay more slowly at greater ΔEsw. We simulated the tension-recovery curve to examine the effect of ΔEsw on the hysteresis loss and permanent deformation of PVNs, finding an optimal value to achieve its minimum energy dissipation and maximum recovery ratio. Lastly, we investigated the efficiency of self-healing by building and removing walls from the system. Interestingly, a maximum self-healing efficiency of the stress-strain behavior is observed at moderate ΔEsw. Overall, this study provides valuable insights into the relationship between the structure and properties of PVNs, offering implications for the manipulation of their mechanical properties and enhancement of their self-healing capabilities.

6.
Biomacromolecules ; 25(2): 626-643, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38157476

RESUMO

Lignin is a class of organic aromatic polymers contributing to the rigidity and strength of plants and has been proposed as a modifier to improve asphalt performance on road pavement. However, contradicting experimental results on the lignin miscibility in asphalt were found from different studies, and lignin has been found to self-assemble in different solutions. Thus, investigating the interaction and microstructure of lignin in asphalt media in molecular detail is necessary. Molecular dynamics (MD) simulations using both the LAMMPS program with the OPLS-aa force field and the NAMD program with the CHARMM force field have been conducted on pure lignin (including lignin monomer, dimer, and polymer with 17 and 31 units) and their mixtures with model asphalt molecules at different temperatures. Consistent results were observed from both programs and force fields in terms of density, hydrogen bonds, diffusion coefficient, radius of gyration, and radial distribution function. Glass transition was observed in the pure lignin systems based on density and diffusion coefficient calculations at different temperatures. Lignin can form intramolecular hydrogen bonds and intermolecular hydrogen bonds with other lignin and 1,7-dimethylnapthalene in the asphalt mixture, which has dependence on temperature and lignin chain length. Correlating the lignin size and chain length using the power-law relationship showed that lignin polymers in pure systems are in quasi-relaxed structures at different temperatures; lignin molecules stay in quasi-relaxed structures in asphalt mixtures at high temperatures but in collapsed structures at low temperatures. Implementing lignin monomer, dimer, and polymer into the model asphalt mixture can improve its density. Although lignin in different chain lengths aggregates in asphalt, lignin can modify the packing between different components in asphalt media at different temperatures. The work suggests that temperature can significantly influence the miscibility of lignin polymer in asphalt and that lignin can function as both a modifier and a resin in asphalt.


Assuntos
Hidrocarbonetos , Lignina , Simulação de Dinâmica Molecular , Bandagens , Polímeros
7.
Macromol Rapid Commun ; : e2400295, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771981

RESUMO

Theoretically, separating the positive and negative charge centers of the chain segments of dielectric elastomers (DEs) is a viable alternative to the conventional decoration of chain backbone with polar handles, since it can dramatically increase the dipole vector and hence the dielectric constant (ε') of the DEs while circumvent the undesired impact of the decorated polar handles on the dielectric loss (tan δ). Herein, a novel and universal method is demonstrated to achieve effective separation of the charge centers of chain segments in homogeneous DEs by steric hindrance engineering, i.e., by incorporating a series of different included angle-containing building blocks into the networks. Both experimental and simulation results have shown that the introduction of these building blocks can create a spatially fixed included angle between two adjacent chain segments, thus separating the charge center of the associated region. Accordingly, incorporating a minimal amount of these building blocks (≈5 mol%) can lead to a considerably sharp increase (≈50%) in the ε' of the DEs while maintaining an extremely low tan δ (≈0.006@1 kHz), indicating that this methodology can substantially optimize the dielectric performance of DEs based on a completely different mechanism from the established methods.

8.
Arch Phys Med Rehabil ; 105(3): 480-486, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37714505

RESUMO

OBJECTIVES: To investigate shoulder, elbow and wrist proprioception impairment poststroke. DESIGN: Proprioceptive acuity in terms of the threshold detection to passive motion at the shoulder, elbow and wrist joints was evaluated using an exoskeleton robot to the individual joints slowly in either inward or outward direction. SETTING: A university research laboratory. PARTICIPANTS: Seventeen stroke survivors and 17 healthy controls (N=34). Inclusion criteria of stroke survivors were (1) a single stroke; (2) stroke duration <1 year; and (3) cognitive ability to follow simple instructions. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Threshold detection to passive motion and detection error at the shoulder, elbow and wrist. RESULTS: There was significant impairment of proprioceptive acuity in stroke survivors as compared to healthy group at all 3 joints and in both the inward (shoulder horizontal adduction, elbow and wrist flexion, P<.01) and outward (P<.01) motion. Furthermore, the distal wrist joint showed more severe impairment in proprioception than the proximal shoulder and elbow joints poststroke (P<.01) in inward motion. Stroke survivors showed significantly larger detection error in identifying the individual joint in motion (P<.01) and the movement direction (P<.01) as compared to the healthy group. There were significant correlations among the proprioception acuity across the shoulder, elbow and wrist joints and 2 movement directions poststroke. CONCLUSIONS: There were significant proprioceptive sensory impairments across the shoulder, elbow and wrist joints poststroke, especially at the distal wrist joint. Accurate evaluations of multi-joint proprioception deficit may help guide more focused rehabilitation.


Assuntos
Articulação do Cotovelo , Acidente Vascular Cerebral , Humanos , Punho , Cognição , Propriocepção , Acidente Vascular Cerebral/complicações
9.
Neoplasma ; 71(1): 77-87, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38506032

RESUMO

The prognosis of advanced lung adenocarcinoma (LUAD) remains unfavorable, with chemotherapy constituting a primary treatment modality. Discerning the efficacy of chemotherapy for advanced LUAD is imperative. Prior investigations have demonstrated the prognostic value of albumin and D-dimer individually for malignancies; however, the predictive capacity of albumin-to-D-dimer ratios (ADR) for advanced LUAD subjected to first-line platinum-based chemotherapy remains unexplored. A cohort of 313 patients with advanced LUAD was retrospectively examined in this study, spanning from January 2017 to January 2021. ADR threshold values were ascertained via receiver operating characteristic analysis, followed by the evaluation of the association between pretreatment ADR and clinicopathological characteristics, disease control rate (DCR), and overall response rate (ORR) pertinent to first-line chemotherapy. Prognostic factors for progression-free survival (PFS) were determined employing Cox univariate and multivariate analyses. Subsequently, survival data were illustrated utilizing the Kaplan-Meier method and scrutinized through the log-rank test across the entire and subgroup populations. ADR demonstrated a superior area under the curve (AUC) value relative to albumin and D-dimer individually and exhibited enhanced prognostic predictive capability compared to albumin-to-fibrinogen ratios (AFR) for advanced LUAD (AUC: 0.805 vs. 0.640, DeLong test: p<0.001). ADR yielded a cut-off value of 16.608. A greater proportion of non-smokers was observed within the high-ADR group (ADR>16.608) compared to the low-ADR group (ADR≤16.608). Patients in the high-ADR group displayed elevated BMI and Na+ levels and reduced neutrophil count, monocyte count, globulin, and alkaline phosphatase (all p<0.05). Notably, the high-ADR group exhibited heightened DCR (96.7% vs. 89.2%, p=0.008) and ORR rates (70.1% vs. 51.0%, p=0.001) relative to the low-ADR group. Multivariate analysis outcomes indicated that high ADR constituted an independent risk factor for PFS (hazard ratio: 0.24, p<0.001). Furthermore, patients in the high-ADR cohort displayed a significantly prolonged median PFS (254 vs. 142 days, p<0.0001) compared to their low-ADR counterparts. In subpopulations exhibiting favorable implications for PFS, as determined by multivariate analysis, high-ADR patients consistently demonstrated extended PFS durations relative to the low-ADR group (all p<0.0001). Collectively, our findings suggest that ADR constitutes a novel and promising prognostic indicator for advanced LUAD patients, surpassing the accuracy of albumin and D-dimer individually and AFR. ADR thus serves as a potent instrument for assessing treatment effects and PFS in advanced LUAD patients undergoing first-line chemotherapy.


Assuntos
Adenocarcinoma de Pulmão , Produtos de Degradação da Fibrina e do Fibrinogênio , Neoplasias Pulmonares , Humanos , Neoplasias Pulmonares/patologia , Prognóstico , Estudos Retrospectivos , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/patologia , Albuminas/uso terapêutico
10.
BMC Musculoskelet Disord ; 25(1): 97, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38279094

RESUMO

BACKGROUND: Finite element analysis (FEA) was performed to investigate the biomechanical differences between different adjunct fixation methods for oblique lumbar interbody fusion (OLIF) and to further analyze its effect on adjacent segmental degeneration. METHODS: We built a single-segment (Si-segment) finite element model (FEM) for L4-5 and a double-segment (Do-segment) FEM for L3-5. Each complete FEM was supplemented and modified, and both developed two surgical models of OLIF with assisted internal fixation. They were OLIF with posterior bilateral percutaneous pedicle screw (TINA system) fixation (OLIF + BPS) and OLIF with lateral plate system (OLIF + LPS). The range of motion (ROM) and displacement of the vertebral body, cage stress, adjacent segment disc stress, and spinal ligament tension were recorded for the four models during flexion/extension, right/left bending, and right/left rotation by applying follower load. RESULTS: For the BPS and LPS systems in the six postures of flexion, extension, right/left bending, and right/left rotation, the ROM of L4 in the Si-segment FEM were 0.32°/1.83°, 0.33°/1.34°, 0.23°/0.47°, 0.24°/0.45°, 0.33°/0.79°, and 0.34°/0.62°; the ROM of L4 in the Do-segment FEM were 0.39°/2.00°, 0.37°/1.38°, 0.23°/0.47°, 0.21°/0.44°, 0.33°/0.57°, and 0.31°/0.62°, and the ROM of L3 in the Do-segment FEM were 6.03°/7.31°, 2.52°/3.50°, 4.21°/4.38°, 4.21°/4.42°, 2.09°/2.32°, and 2.07°/2.43°. BPS system had less vertebral displacement, less cage maximum stress, and less spinal ligament tension in Si/Do-segment FEM relative to the LPS system. BPS system had a smaller upper adjacent vertebral ROM, greater intervertebral disc stress in terms of left and right bending as well as left and right rotation compared to the LPS system in the L3-4 of the Do-segment FEM. There was little biomechanical difference between the same fixation system in the Si/Do-segment FEM. CONCLUSIONS: Our finite element analysis showed that compared to OLIF + LPS, OLIF + BPS (TINA) is more effective in reducing interbody stress and spinal ligament tension, and it better maintains the stability of the target segment and provides a better fusion environment to resist cage subsidence. However, OLIF + BPS (TINA) may be more likely to cause adjacent segment degeneration than OLIF + LPS.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Humanos , Análise de Elementos Finitos , Lipopolissacarídeos , Vértebras Lombares/cirurgia , Fusão Vertebral/métodos , Fenômenos Biomecânicos , Amplitude de Movimento Articular
11.
Artigo em Inglês | MEDLINE | ID: mdl-38758147

RESUMO

Objective: To evaluate the implementation and effectiveness of progressive rehabilitation nursing in patients undergoing modified radical mastectomy for breast cancer. Methods: A total of 70 patients undergoing modified radical mastectomy for breast cancer in our hospital were selected as the research subjects, and they were randomly divided into a control group and an observation group, with 35 patients in each group. The control group received routine rehabilitation nursing intervention after surgery, while the observation group received progressive rehabilitation nursing intervention based on the control group's nursing. The quality of life, self-care ability, mental state, and incidence of complications were compared between the two groups. Results: Before the intervention, the two groups had no significant difference in the quality of life (P > .05). After the intervention, the quality of life in the observation group was significantly better than that in the control group (P < .05). Before the intervention, the two groups had no significant difference in the self-care ability (P > .05). After the intervention, the self-care ability in the observation group was significantly better than that in the control group (P < .05). Before the intervention, the two groups had no significant difference in the SAS and SDS scores (P > .05). After the intervention, the SAS and SDS scores in the observation group were significantly lower than those in the control group (P < .05). The incidence of complications in the control group was 22.86%, while that in the observation group was 5.71%. The incidence of complications in the observation group was significantly lower than in the control group (P < .05). Conclusion: Compared with routine nursing intervention, the implementation of progressive rehabilitation nursing intervention can further improve the quality of life, self-care ability, and mental state of patients undergoing modified radical mastectomy for breast cancer and reduce the risk of related complications, which helps promote the recovery process of patients and is worthy of clinical promotion and application.

12.
Ecotoxicol Environ Saf ; 280: 116546, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38843747

RESUMO

In China, fence net aquaculture practices have been established in some subsidence waters that have been formed in coal mining subsidence areas. Within this dynamic ecological context, diverse fish species grow continuously until being harvested at the culmination of their production cycle. The purpose of this study was to investigate diverse factors influencing the bioavailability and distribution of mercury (Hg) and methylmercury (MeHg), which have high physiological toxicity in fish, in the Guqiao coal mining subsidence area in Huainan, China. Mercury and MeHg were analyzed in 38 fish samples of eight species using direct mercury analysis (DMA-80) and gas chromatography-cold vapor atomic fluorescence spectrometry (GC-CVAFAS). The analysis results show that the ranges of Hg and MeHg content and methylation rate in the fish were 7.84-85.18 ng/g, 0.52-3.52 ng/g, and 0.81-42.68 %, respectively. Meanwhile, conclusions are also summarized as following: (1) Monophagous herbivorous fish that were fed continuously in fence net aquaculture areas had higher MeHg levels and mercury methylation rates than carnivorous fish. Hg and MeHg contents were affected by different feeding habits of fish. (2) Bottom-dwelling fish show higher MeHg levels, and habitat selection in terms of water depth also partially affected the MeHg content of fish. (3) The effect of fence net aquaculture on methylation of fish in subsidence water is mainly from feed and mercury-containing bottom sediments. However, a time-lag is observed in the physiological response of benthic fishes to the release of Hg from sediments. Our findings provides baseline reference data for the ecological impact of fence net aquaculture in waters affected by soil subsidence induced by coal mining in China. Prevalent environmental contaminants within coal mining locales, notably Hg, may infiltrate rain-induced subsidence waters through various pathways.


Assuntos
Aquicultura , Minas de Carvão , Monitoramento Ambiental , Peixes , Mercúrio , Compostos de Metilmercúrio , Poluentes Químicos da Água , Compostos de Metilmercúrio/análise , Animais , Mercúrio/análise , Poluentes Químicos da Água/análise , Peixes/metabolismo , China , Monitoramento Ambiental/métodos
13.
Angew Chem Int Ed Engl ; 63(30): e202405287, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38712847

RESUMO

Marangoni self-propulsion refers to motion of liquid or solid driven by a surface tension gradient, and has applications in soft robots/devices, cargo delivery, self-assembly etc. However, two problems remain to be addressed for motion control (e.g., ON-OFF) with conventional surfactants as Marangoni fuel: (1) limited motion lifetime due to saturated interfacial adsorption of surfactants; (2) in- situ motion stop is difficult once Marangoni flows are triggered. Instead of covalent surfactants, supra-amphiphiles with hydrophilic and hydrophobic parts linked noncovalently, hold promise to solve these problems owing to its dynamic and reversible surface activity responsively. Here, we propose a new concept of 'supra-amphiphile fuel and switch' based on the facile synthesis of disodium-4-azobenzene-amino-1,3-benzenedisulfonate (DABS) linked by a Schiff base, which has amphiphilicity for self-propulsion, hydrolyzes timely to avoid saturated adsorption, and provides pH-responsive control over ON-OFF motion. The self-propulsion lifetime is extended by 50-fold with DABS and motion control is achieved. The mechanism is revealed with coupled interface chemistry involving two competitive processes of interfacial adsorption and hydrolysis of DABS based on both experiments and simulation. The concept of 'supra-amphiphile fuel and switch' provides an active solution to prolong and control Marangoni self-propulsive devices for the advance of intelligent material systems.

14.
J Biol Chem ; 298(6): 102027, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35568198

RESUMO

The production of secondary metabolites is a major mechanism used by beneficial rhizobacteria to antagonize plant pathogens. These bacteria have evolved to coordinate the production of different secondary metabolites due to the heavy metabolic burden imposed by secondary metabolism. However, for most secondary metabolites produced by bacteria, it is not known how their biosynthesis is coordinated. Here, we showed that PhlH from the rhizobacterium Pseudomonas fluorescens is a TetR-family regulator coordinating the expression of enzymes related to the biosynthesis of several secondary metabolites, including 2,4-diacetylphloroglucinol (2,4-DAPG), mupirocin, and pyoverdine. We present structures of PhlH in both its apo form and 2,4-DAPG-bound form and elucidate its ligand-recognizing and allosteric switching mechanisms. Moreover, we found that dissociation of 2,4-DAPG from the ligand-binding domain of PhlH was sufficient to allosterically trigger a pendulum-like movement of the DNA-binding domains within the PhlH dimer, leading to a closed-to-open conformational transition. Finally, molecular dynamics simulations confirmed that two distinct conformational states were stabilized by specific hydrogen bonding interactions and that disruption of these hydrogen bonds had profound effects on the conformational transition. Our findings not only reveal a well-conserved route of allosteric signal transduction in TetR-family regulators but also provide novel mechanistic insights into bacterial metabolic coregulation.


Assuntos
Proteínas de Bactérias , Regulação Bacteriana da Expressão Gênica , Pseudomonas fluorescens , Transdução de Sinais , Proteínas de Bactérias/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ligação de Hidrogênio , Ligantes , Mupirocina/metabolismo , Oligopeptídeos/metabolismo , Floroglucinol/metabolismo , Conformação Proteica , Pseudomonas fluorescens/metabolismo , Metabolismo Secundário
15.
BMC Genomics ; 24(1): 13, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36627555

RESUMO

BACKGROUND: Taraxacum kok-saghyz Rodin (TKS) is a promising commercial alternative natural rubber (NR) yielding plant. Cultivating TKS with a high NR content is an important breeding target, and developing molecular markers related to NR content can effectively accelerate the breeding process of TKS. RESULTS: To construct a high-density SNP genetic map and uncover genomic regions related to the NR content in TKS, an F1 mapping population of TKS was constructed by crossing two parents (l66 and X51) with significant differences in NR contents. The NR content of the F1 plants ranged from 0.30 to 15.14% and was distributed normally with a coefficient of variation of 47.61%, indicating quantitative trait inheritance. Then, employing whole-genome resequencing (WGR), a TKS genetic linkage map of 12,680 bin markers comprising 322,439 SNPs was generated. Based on the genetic map and NR content of the F1 population, six quantitative trait loci (QTLs) for NR content with LOD > 4.0 were identified on LG01/Chr01 and LG06/Chr06. Of them, the 2.17 Mb genomic region between qHRC-C6-1 and qHRC-C6-2 on ChrA06, with 65.62% PVE in total, was the major QTL region. In addition, the six QTLs have significant additive genetic effects on NR content and could be used to develop markers for marker-assisted selection (MAS) in TKS with a high NR content. CONCLUSION: This work constructed the first high-density TKS genetic map and identified the QTLs and genomic regions controlling the NR content, which provides useful information for fine mapping, map-based cloning, and MAS in TKS.


Assuntos
Locos de Características Quantitativas , Taraxacum , Borracha , Taraxacum/genética , Polimorfismo de Nucleotídeo Único , Melhoramento Vegetal , Fenótipo , Ligação Genética
16.
Br J Cancer ; 128(9): 1723-1732, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36807337

RESUMO

BACKGROUND: A non-invasive endometrial cancer detection tool that can accurately triage symptomatic women for definitive testing would improve patient care. Urine is an attractive biofluid for cancer detection due to its simplicity and ease of collection. The aim of this study was to identify urine-based proteomic signatures that can discriminate endometrial cancer patients from symptomatic controls. METHODS: This was a prospective case-control study of symptomatic post-menopausal women (50 cancers, 54 controls). Voided self-collected urine samples were processed for mass spectrometry and run using sequential window acquisition of all theoretical mass spectra (SWATH-MS). Machine learning techniques were used to identify important discriminatory proteins, which were subsequently combined in multi-marker panels using logistic regression. RESULTS: The top discriminatory proteins individually showed moderate accuracy (AUC > 0.70) for endometrial cancer detection. However, algorithms combining the most discriminatory proteins performed well with AUCs > 0.90. The best performing diagnostic model was a 10-marker panel combining SPRR1B, CRNN, CALML3, TXN, FABP5, C1RL, MMP9, ECM1, S100A7 and CFI and predicted endometrial cancer with an AUC of 0.92 (0.96-0.97). Urine-based protein signatures showed good accuracy for the detection of early-stage cancers (AUC 0.92 (0.86-0.9)). CONCLUSION: A patient-friendly, urine-based test could offer a non-invasive endometrial cancer detection tool in symptomatic women. Validation in a larger independent cohort is warranted.


Assuntos
Biomarcadores Tumorais , Neoplasias do Endométrio , Humanos , Feminino , Estudos de Casos e Controles , Proteômica/métodos , Biomarcadores , Espectrometria de Massas/métodos , Neoplasias do Endométrio/diagnóstico , Proteínas de Ligação a Ácido Graxo , Proteínas da Matriz Extracelular
17.
Ann Surg ; 277(4): e777-e784, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35129490

RESUMO

OBJECTIVE: To evaluate the long-term and short-term outcomes of MIE compared with OE in localized ESCC patients in real-world settings. BACKGROUND: MIE is an alternative to OE, despite the limited evidence regarding its effect on long-term survival. METHODS: We recruited 5822 consecutive patients with resectable ESCC in 2 typical high-volume centers in southern and northern China, 1453 of whom underwent MIE. Propensity score-based overlap weighted regression adjusted for multifaceted confounding factors was used to compare outcomes in the MIE and OE groups. RESULTS: Five-year OS was 62.7% in the MIE group and 57.7% in the OE group. The overlap weighted Cox regression showed slightly better OS in the MIE group (hazard ratio 0.93, 95% confidence interval: 0.82-1.06). Although duration of surgery was longer and treatment cost higher in the MIE group than in the OE group, the number of lymph nodes harvested was larger, the proportion of intraoperative blood transfusions lower, and postoperative complications less in the MIE group. 30-day (risk ratio [RR] 0.77, 0.381.55) and 90-day (RR 0.79, 0.46-1.35) mortality were lower in the MIE group versus the OE group, although not statistically significant. These findings were consistent across different analytic approaches and subgroups, notably in the subset of ESCC patients with large tumors. CONCLUSIONS: MIE can be performed safely with OS comparable to OE for patients with localized ESCC, indicating MIE may be recommended as the primary surgical approach for resectable ESCC in health facilities with requisite technical capacity.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/cirurgia , Resultado do Tratamento , Esofagectomia/efeitos adversos , Estudos Retrospectivos , Procedimentos Cirúrgicos Minimamente Invasivos/efeitos adversos , Complicações Pós-Operatórias/etiologia
18.
Lancet ; 400(10346): 104-115, 2022 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-35810756

RESUMO

BACKGROUND: Whether thrombectomy alone is equally as effective as intravenous alteplase plus thrombectomy remains controversial. We aimed to determine whether thrombectomy alone would be non-inferior to intravenous alteplase plus thrombectomy in patients presenting with acute ischaemic stroke. METHODS: In this multicentre, randomised, open-label, blinded-outcome trial in Europe and Canada, we recruited patients with stroke due to large vessel occlusion confirmed with CT or magnetic resonance angiography admitted to endovascular centres. Patients were randomly assigned (1:1) via a centralised web server using a deterministic minimisation method to receive stent-retriever thrombectomy alone or intravenous alteplase plus stent-retriever thrombectomy. In both groups, thrombectomy was initiated as fast as possible with any commercially available Solitaire stent-retriever revascularisation device (Medtronic, Irvine, CA, USA). In the combined treatment group, intravenous alteplase (0·9 mg/kg bodyweight, maximum dose 90 mg per patient) was administered as early as possible after randomisation for 60 min with 10% of the calculated dose given as an initial bolus. Personnel assessing the primary outcome were masked to group allocation; patients and treating physicians were not. The primary binary outcome was a score of 2 or less on the modified Rankin scale at 90 days. We assessed the non-inferiority of thrombectomy alone versus intravenous alteplase plus thrombectomy in all randomly assigned and consenting patients using the one-sided lower 95% confidence limit of the Mantel-Haenszel risk difference, with a prespecified non-inferiority margin of 12%. The main safety endpoint was symptomatic intracranial haemorrhage assessed in all randomly assigned and consenting participants. This trial is registered with ClinicalTrials.gov, NCT03192332, and is closed to new participants. FINDINGS: Between Nov 29, 2017, and May 7, 2021, 5215 patients were screened and 423 were randomly assigned, of whom 408 (201 thrombectomy alone, 207 intravenous alteplase plus thrombectomy) were included in the primary efficacy analysis. A modified Rankin scale score of 0-2 at 90 days was reached by 114 (57%) of 201 patients assigned to thrombectomy alone and 135 (65%) of 207 patients assigned to intravenous alteplase plus thrombectomy (adjusted risk difference -7·3%, 95% CI -16·6 to 2·1, lower limit of one-sided 95% CI -15·1%, crossing the non-inferiority margin of -12%). Symptomatic intracranial haemorrhage occurred in five (2%) of 201 patients undergoing thrombectomy alone and seven (3%) of 202 patients receiving intravenous alteplase plus thrombectomy (risk difference -1·0%, 95% CI -4·8 to 2·7). Successful reperfusion was less common in patients assigned to thrombectomy alone (182 [91%] of 201 vs 199 [96%] of 207, risk difference -5·1%, 95% CI -10·2 to 0·0, p=0·047). INTERPRETATION: Thrombectomy alone was not shown to be non-inferior to intravenous alteplase plus thrombectomy and resulted in decreased reperfusion rates. These results do not support omitting intravenous alteplase before thrombectomy in eligible patients. FUNDING: Medtronic and University Hospital Bern.


Assuntos
Acidente Vascular Cerebral , Trombectomia , Ativador de Plasminogênio Tecidual , Fibrinolíticos/efeitos adversos , Humanos , Hemorragias Intracranianas/etiologia , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Ativador de Plasminogênio Tecidual/efeitos adversos , Resultado do Tratamento
19.
Langmuir ; 39(31): 11003-11015, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37493597

RESUMO

Densely grafted polymer chains onto spherical nanoparticles produce a diverse range of conformations. At high grafting densities, the corona region near the nanoparticle surface undergoes intense confinement due to a high concentration of chains in the concentrated polymer brush (CPB) region, which results in strong stretching for portions of the chains located within. In contrast, a semi-dilute polymer brush (SDPB) forms farther away from the core and offers reduced confinement for the polymer and more ideal conformations. However, conventional experimental methods are limited in their ability to provide detailed information on individual segments of grafted polymers in these regions; hence, molecular dynamics (MD) simulations are essential for gaining comprehensive insights into the behavior of the grafted chains. This study aims to explore the variations in polymer structure and dynamics that occur along the contour of the grafted chains as influenced by spatial confinement. We focus on the motions and relative positions of each bead along grafted polymers. Our results show that only the initial few grafted beads near the nanoparticle surface exhibit the strong stretching attributed segments in the CPB region of the brush. Increased grafting density or decreased chain flexibility leads to more stretched grafted chains and more aligned bond vectors. As a result, the relaxation dynamics of local regions of the polymer are also strongly influenced by these parameters. Although the grafted beads in the interior of the CPB region are highly sensitive to these parameters, those farther from the nanoparticle core experience significantly diminished effects. In comparison to the Daoud-Cotton (DC) model's predictions of CPB size, beads near the nanoparticle surface show slower dynamic decay, especially in high grafting densities, aligning with the DC model's estimates. Finally, we compare our simulations to previous works for additional insight into polymer-grafted nanoparticles.

20.
Langmuir ; 39(28): 9703-9714, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37417905

RESUMO

The reverse non-equilibrium molecular dynamics simulation is used to investigate the influence of functional groups (FGs) on the thermal conductivity of a graphene/poly(vinyl alcohol) (PVA) composite, which considers non-polar (methyl) and polar (hydroxyl, amino, and carboxyl) groups. First, the polar groups can be more effective to improve the interfacial thermal conductivity than the non-polar group. This can be explained well by characterizing the interfacial Coulombic energy, number and lifetime of hydrogen bonds, vibrational density of states, and integrated autocorrelation of the interfacial heat power. Moreover, the hydroxyl group can improve the interfacial thermal conductivity more than the other groups, which can be rationalized by analyzing the surface roughness of graphene and the radial distribution function of FGs and the PVA chains. However, the introduction of FGs destroys the graphene structure, which consequently reduces the intrinsic thermal conductivity. Furthermore, by adopting the effective medium approximation model and finite element method, there exists a critical graphene length where the overall thermal conductivities are equal for the functionalized and pristine graphene. Finally, the distribution state of graphene is emphasized to be more vital in determining the overall thermal conductivity than the generally accepted interfacial thermal conductivity.

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