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1.
Cell ; 184(16): 4251-4267.e20, 2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34260899

RESUMO

Genetic recombination generates novel trait combinations, and understanding how recombination is distributed across the genome is key to modern genetics. The PRDM9 protein defines recombination hotspots; however, megabase-scale recombination patterning is independent of PRDM9. The single round of DNA replication, which precedes recombination in meiosis, may establish these patterns; therefore, we devised an approach to study meiotic replication that includes robust and sensitive mapping of replication origins. We find that meiotic DNA replication is distinct; reduced origin firing slows replication in meiosis, and a distinctive replication pattern in human males underlies the subtelomeric increase in recombination. We detected a robust correlation between replication and both contemporary and historical recombination and found that replication origin density coupled with chromosome size determines the recombination potential of individual chromosomes. Our findings and methods have implications for understanding the mechanisms underlying DNA replication, genetic recombination, and the landscape of mammalian germline variation.


Assuntos
Células Germinativas/citologia , Recombinação Homóloga , Meiose , Animais , Composição de Bases/genética , Cromossomos de Mamíferos/genética , Quebras de DNA de Cadeia Dupla , Replicação do DNA , Genoma , Células Germinativas/metabolismo , Humanos , Masculino , Mamíferos/metabolismo , Camundongos , Origem de Replicação , Fase S , Telômero/metabolismo , Testículo/citologia
2.
Small ; 20(12): e2307393, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37897146

RESUMO

Described here are sterically hindered tetradentate [Pt(O^N^C^N)] emitters (Pt-1, Pt-2, and Pt-3) developed for stable and high-performance green phosphorescent organic light-emitting diodes (OLEDs). These Pt(II) emitters exhibit strong saturated green phosphorescence (λmax = 517-531 nm) in toluene and mCP thin films with emission quantum yields as high as 0.97, radiative rate constants (kr) as high as 4.4-5.3 × 105 s-1 and reduced excimer emission, and with a preferential horizontally oriented transition dipole ratio of up to 84%. Theoretical calculations show that p-(hetero)arene substituents at the periphery of the ligand scaffolds in Pt-1, Pt-2, and Pt-3 can i) enhance the spin-orbit coupling (SOC) between the lower singlet excited states and the T1 state, and S0→Sn (n = 1 or 2) transition dipole moment, and ii) introducing additional SOC activity and the bright 1ILCT[π(carbazole)→π*(N^C^N)] excited state (Pt-2 and Pt-3), which are the main contributors to the increased kr values. Utilizing these tetradentate Pt(II) emitters, green phosphorescent OLEDs are fabricated with narrow-band electroluminescence (FWHM down to 36 nm), high external quantum efficiency, current efficiency up to 27.6% and 98.7 cd A-1, and an unprecedented device lifetime (LT95) of up to 9270 h at 1000 cd m-2 under laboratory conditions.

3.
Small ; 20(23): e2309318, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38174636

RESUMO

Graphene, a promising material with excellent properties, suffers from a major limitation in electronics due to its zero bandgap. The gas molecules adsorption has proven to be an effective approach for band regulation, which usually requires a harsh environment. Here, O2 - ions produced with triboelectric plasma are used for in situ regulation of graphene, and the switching ratio can reach 1010. The O2 - ions physical adsorption will reduce the Fermi-level (EF) of graphene. As the EF of graphene is lower than the lowest unoccupied molecular orbital (LUMO) level of O2-, the adsorption of O2 - changes from uniform physical adsorption to local chemical adsorption, thereby realizing the semiconductor properties of graphene. The local graphene bandgap is calculated to be 83.4 meV by the variable-temperature experiment. Furthermore, annealing treatment can restore to 1/10 of the initial conductance. The C─O bond formed by O2 - adsorption has low bond energy and is easy to desorb, while the C═O bond formed by adsorption on defects and edges has higher bond energy and is difficult to desorb. The study proposes a simple in situ method to investigate the microscopic process of O2 - adsorption on the graphene surface, demonstrating a new perspective for local energy band engineering of graphene.

4.
Small ; : e2400961, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38534173

RESUMO

Functionalized nanochannels can convert environmental thermal energy into electrical energy by driving water evaporation. This process involves the interaction between the solid-liquid interface and the natural water evaporation. The evaporation-driven water potential effect is a novel green environmental energy capture technology that has a wide range of applications and does not depend on geographical location or environmental conditions, it can generate power as long as there is water, light, and heat. However, suitable materials and structures are needed to harness this natural process for power generation. MOF materials are an emerging field for water evaporation power generation, but there are still many challenges to overcome. This work uses MOF-801, which has high porosity, charged surface, and hydrophilicity, to enhance the output performance of evaporation-driven power generation. It can produce an open circuit voltage of ≈2.2 V and a short circuit current of ≈1.9 µA. This work has a simple structure, easy preparation, low-cost and readily available materials, and good stability. It can operate stably in natural environments with high practical value.

5.
Eur J Clin Invest ; 54(6): e14179, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38363025

RESUMO

BACKGROUND: Emerging data suggested that lipoprotein(a) [Lp(a)] is an independent risk factor for atherosclerotic cardiovascular disease. Previous studies indicated fibrinogen (Fib) had synergetic effect on Lp(a)-induced events. However, combined impact of Fib and Lp(a) on ischemic stroke has not been elucidated. METHODS: In this prospective study, we consecutively enrolled 8263 patients with stable coronary artery diseases (CAD) from 2011 to 2017. Patients were categorized into three groups according to tertiles of Lp(a) levels [Lp(a)-low, Lp(a)-medium, and Lp(a)-high] and further divided into nine groups by Lp(a) and Fib levels. All subjects were followed up for the occurrence of ischemic stroke. RESULTS: During a median follow-up of 37.7 months, 157 (1.9%) ischemic strokes occurred. Stroke incidence increased by Lp(a) (1.1 vs. 2.1 vs. 2.5%, Cochran-Armitage p < .001) and Fib (1.1 vs. 2.0 vs. 2.6%, Cochran-Armitage p < .001) categories. When further classified into nine groups by Lp(a) and Fib levels, the incidence of ischemic stroke in group 9 [Lp(a)-high and Fib-high] was significantly higher than that in group 1 [Lp(a)-low and Fib-low] (3.1 vs. 6%, p < .001). The group 9 was associated with a highest risk for ischemic stroke (adjusted HR 4.907, 95% CI: 2.154-11.18, p < .001), compared with individuals in the Lp(a)-high (adjusted HR 2.290, 95% CI: 1.483-3.537, p < .001) or Fib-high (adjusted HR 1.184, 95% CI: 1.399-3.410, p = .001). Furthermore, combining Lp(a) with Fib increased C-statistics by .045 (p = .004). CONCLUSIONS: Current study first demonstrated that elevated Lp(a) combining with Fib evaluation enhanced the risk of ischemic stroke in patients with CAD beyond Lp(a) or Fib alone.


Assuntos
Doença da Artéria Coronariana , Fibrinogênio , AVC Isquêmico , Lipoproteína(a) , Humanos , Lipoproteína(a)/sangue , Lipoproteína(a)/metabolismo , Fibrinogênio/metabolismo , Masculino , Feminino , Doença da Artéria Coronariana/epidemiologia , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , AVC Isquêmico/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Incidência , Fatores de Risco
6.
Nanotechnology ; 35(18)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38271735

RESUMO

A single ZnO nanowire device with volatile resistive switching behavior has been prepared. Different from traditional resistive switching devices, such ZnO nanowire devices do not exhibit resistive switching behaviors under a single bias voltage, and appear resistive switching behavior under the combined action of light stimuli and bias voltage. Through the demonstration of the time-dependent hysteresis curve and atmosphere-dependent hysteresis loop of the resistive switching devices, it is believed that under the resistive switching process, ultraviolet illumination can increase the carrier concentration and modulate the barrier depletion structure, and external bias voltage can ionize the surface state. They work together to modulate the switching process of the devices. Such light stimuli and bias voltage dual-modulated resistive switching device enables optical control and may thus be considered for sensory applications or optically tunable memories.

7.
Nanotechnology ; 35(13)2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37802048

RESUMO

Sliding grating-structured triboelectric nanogenerators (SG-TENGs) can multiply transferred charge, reduce open-circuit voltage, and increase short-circuit current, which have wide application prospects in self-powered systems. However, conventional SG-TENGs have an ultrahigh internal equivalent impedance, which reduces the output voltage and energy under low load resistances (<10 MΩ). The Pulsed SG-TENGs can reduce the equivalent impedance to near zero by introducing a synchronously triggered mechanical switch (STMS), but its limited output time causes the incomplete charge transfer under high load resistances (>1 GΩ). In this paper, a conventional and pulsed hybrid SG-TENG (CPH-SG-TENG) is developed through rational designing STMS with tunable width and output time. The matching relationship among grid electrode width, contactor width of STMS, sliding speed, and load resistance has been studied, which provides a feasible solution for simultaneous realization of high output energy under small load resistances and high output voltage under high load resistances. The impedance matching range is extended from zero to at least 10 GΩ. The output performance of CPH-SG-TENG under low and high load resistances are demonstrated by passive power management circuit and arc discharge, respectively. The general strategy using tunable STMS combines the advantages of conventional and pulsed TENGs, which has broad application prospects in the fields of TENGs and self-powered systems.

8.
Chem Rev ; 122(23): 17073-17154, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36201481

RESUMO

The term "zwitterionic polymers" refers to polymers that bear a pair of oppositely charged groups in their repeating units. When these oppositely charged groups are equally distributed at the molecular level, the molecules exhibit an overall neutral charge with a strong hydration effect via ionic solvation. The strong hydration effect constitutes the foundation of a series of exceptional properties of zwitterionic materials, including resistance to protein adsorption, lubrication at interfaces, promotion of protein stabilities, antifreezing in solutions, etc. As a result, zwitterionic materials have drawn great attention in biomedical and engineering applications in recent years. In this review, we give a comprehensive and panoramic overview of zwitterionic materials, covering the fundamentals of hydration and nonfouling behaviors, different types of zwitterionic surfaces and polymers, and their biomedical applications.


Assuntos
Materiais Biocompatíveis , Polímeros , Adsorção , Proteínas
9.
Bioorg Chem ; 149: 107506, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38833989

RESUMO

Janus kinases (JAKs), a kind of non-receptor tyrosine kinases, the function has been implicated in the regulation of cell proliferation, differentiation and apoptosis, immune, inflammatory response and malignancies. Among them, JAK1 represents an essential target for modulating cytokines involved in inflammation and immune function. Rheumatoid arthritis, atopic dermatitis, ulcerative colitis and psoriatic arthritis are areas where approved JAK1 drugs have been applied for the treatment. In the review, we provided a brief introduction to JAK1 inhibitors in market and clinical trials. The structures of high active JAK1 compounds (IC50 ≤ 0.1 nM) were highlighted, with primary focus on structure-activity relationship and selectivity. Moreover, the druggability processes of approved drugs and high active compounds were analyzed. In addition, the issues involved in JAK1 compounds clinical application as well as strategies to surmount these challenges, were discussed.


Assuntos
Janus Quinase 1 , Inibidores de Proteínas Quinases , Relação Estrutura-Atividade , Humanos , Janus Quinase 1/antagonistas & inibidores , Janus Quinase 1/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/síntese química , Estrutura Molecular , Animais , Relação Dose-Resposta a Droga
10.
Nature ; 560(7720): 582-588, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30158607

RESUMO

The Newtonian gravitational constant, G, is one of the most fundamental constants of nature, but we still do not have an accurate value for it. Despite two centuries of experimental effort, the value of G remains the least precisely known of the fundamental constants. A discrepancy of up to 0.05 per cent in recent determinations of G suggests that there may be undiscovered systematic errors in the various existing methods. One way to resolve this issue is to measure G using a number of methods that are unlikely to involve the same systematic effects. Here we report two independent determinations of G using torsion pendulum experiments with the time-of-swing method and the angular-acceleration-feedback method. We obtain G values of 6.674184 × 10-11 and 6.674484 × 10-11 cubic metres per kilogram per second squared, with relative standard uncertainties of 11.64 and 11.61 parts per million, respectively. These values have the smallest uncertainties reported until now, and both agree with the latest recommended value within two standard deviations.

11.
J Exp Child Psychol ; 243: 105928, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38643735

RESUMO

Previous studies have shown that adults exhibit the strongest attentional bias toward neutral infant faces when viewing faces with different expressions at different attentional processing stages due to different stimulus presentation times. However, it is not clear how the characteristics of the temporal processing associated with the strongest effect change over time. Thus, we combined a free-viewing task with eye-tracking technology to measure adults' attentional bias toward infant and adult faces with happy, neutral, and sad expressions of the same face. The results of the analysis of the total time course indicated that the strongest effect occurred during the strategic processing stage. However, the results of the analysis of the split time course revealed that sad infant faces first elicited adults' attentional bias at 0 to 500 ms, whereas the strongest effect of attentional bias toward neutral infant faces was observed at 1000 to 3000 ms, peaking at 1500 to 2000 ms. In addition, women and men had no differences in their responses to different expressions. In summary, this study provides further evidence that adults' attentional bias toward infant faces across stages of attention processing is modulated by expressions. Specifically, during automatic processing adults' attentional bias was directed toward sad infant faces, followed by a shift to the processing of neutral infant faces during strategic processing, which ultimately resulted in the strongest effect. These findings highlight that this strongest effect is dynamic and associated with a specific time window in the strategic process.


Assuntos
Viés de Atenção , Expressão Facial , Reconhecimento Facial , Humanos , Feminino , Masculino , Viés de Atenção/fisiologia , Adulto Jovem , Adulto , Reconhecimento Facial/fisiologia , Lactente , Tecnologia de Rastreamento Ocular , Atenção , Fatores de Tempo
12.
J Appl Toxicol ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38462915

RESUMO

Acute pancreatitis represents an inflammatory disease featuring pancreatic necrosis and inflammation. Inflammatory injury of pancreatic acinar cells (PACs) is critically involved in the initiation and progression of acute pancreatitis. Pyroptosis, a new kind of programmed cell death concomitant with a low-grade inflammatory reaction, plays a function in acute pancreatitis pathology. It is unclear whether saikosaponin d (SSd), a pharmacologically active natural product, could protect PACs by regulating pyroptosis. Here, we established a PAC injury model in vitro using cerulein to treat AR42J cells. SSd restored viability and proliferation and lowered the release of pancreatic enzymes and inflammatory interleukins in cerulein-treated AR42J cells. Cerulein-induced pyroptosis was evidenced by typical ultrastructural changes and NLRP3/caspase-1 activation in AR42J cells, but SSd attenuated cerulein-induced pyroptosis and inhibited NLRP3/caspase-1 pathway. Mechanically, SSd reduced mitochondrial damage and mtDNA release, and blocked cGAS-STING signaling in AR42J cells treated with cerulein, contributing to the inhibition of NLRP3-mediated pyroptosis. Furthermore, SSd abolished cerulein-elevated oxidative stress in AR42J cells, leading to the mitigation of mitochondrial damage and inhibition of cGAS-STING signaling and pyroptosis. In conclusion, SSd protected PACs against cerulein-induced pyroptosis by alleviating mitochondrial damage and inhibiting the cGAS-STING pathway, and it could be a therapeutic candidate for acute pancreatitis.

13.
Nanomedicine ; 58: 102743, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38484918

RESUMO

Cancer-associated fibroblasts (CAFs) play a crucial role in creating an immunosuppressive environment and remodeling the extracellular matrix within tumors, leading to chemotherapy resistance and limited immune cell infiltration. To address these challenges, integrating CAFs deactivation into immunogenic chemotherapy may represent a promising approach to the reversal of immune-excluded tumor. We developed a tumor-targeted nanomedicine called the glutathione-responsive nanocomplex (GNC). The GNC co-loaded dasatinib, a CAF inhibitor, and paclitaxel, a chemotherapeutic agent, to deactivate CAFs and enhance the effects of immunogenic chemotherapy. Due to the modification with hyaluronic acid, the GNC preferentially accumulated in the tumor periphery and responsively released cargos, mitigating the tumor stroma as well as overcoming chemoresistance. Moreover, GNC treatment exhibited remarkable immunostimulatory efficacy, including CD8+ T cell expansion and PD-L1 downregulation, facilitating immune checkpoint blockade therapy. In summary, the integration of CAF deactivation and immunogenic chemotherapy using the GNC nanoplatform holds promise for rebuilding immune-excluded tumors.


Assuntos
Fibroblastos Associados a Câncer , Paclitaxel , Fibroblastos Associados a Câncer/efeitos dos fármacos , Fibroblastos Associados a Câncer/imunologia , Fibroblastos Associados a Câncer/patologia , Fibroblastos Associados a Câncer/metabolismo , Animais , Humanos , Camundongos , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Dasatinibe/farmacologia , Dasatinibe/uso terapêutico , Neoplasias/imunologia , Neoplasias/tratamento farmacológico , Neoplasias/terapia , Neoplasias/patologia , Linhagem Celular Tumoral , Nanopartículas/química , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Feminino , Glutationa/metabolismo
14.
PLoS Genet ; 17(3): e1009383, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33657091

RESUMO

As both host and pathogen require iron for survival, iron is an important regulator of host-pathogen interactions. However, the molecular mechanism by which how the availability of iron modulates host innate immunity against bacterial infections remains largely unknown. Using the metazoan Caenorhabditis elegans as a model, we demonstrate that infection with a pathogenic bacterium Salmonella enterica serovar Typhimurium induces autophagy by inactivating the target of rapamycin (TOR). Although the transcripts of ftn-1 and ftn-2 encoding two H-ferritin subunits are upregulated upon S. Typhimurium infection, the ferritin protein is kept at a low level due to its degradation mediated by autophagy. Autophagy, but not ferritin, is required for defense against S. Typhimurium infection under normal circumstances. Increased abundance of iron suppresses autophagy by activating TOR, leading to an increase in the ferritin protein level. Iron sequestration, but not autophagy, becomes pivotal to protect the host from S. Typhimurium infection in the presence of exogenous iron. Our results show that TOR acts as a regulator linking iron availability with host defense against bacterial infection.


Assuntos
Infecções Bacterianas/metabolismo , Sinais (Psicologia) , Resistência à Doença/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata , Ferro/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Animais , Autofagia , Infecções Bacterianas/etiologia , Caenorhabditis elegans , Resistência à Doença/genética , Suscetibilidade a Doenças , Ferritinas/metabolismo , Interações Hospedeiro-Patógeno/genética , Humanos , Modelos Biológicos , Salmonella typhimurium/imunologia
15.
Acta Neurochir (Wien) ; 166(1): 289, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980513

RESUMO

PURPOSE: Although ipsilateral C7 nerve transfer is used for the treatment of C5-C6 brachial plexus injuries, accurately evaluating the functional quality of the donor nerve (ipsilateral C7 nerve root) is difficult, especially when the C7 nerve root is slightly injured. The purpose of this study was to determine the indicators to evaluate the quality of the ipsilateral C7 nerve and assess the clinical outcomes of this procedure. METHODS: This study employed the following three indicators to assess the quality of the ipsilateral C7 nerve: (1) the muscle strength and electrophysiological status of the latissimus dorsi, triceps brachii, and extensor digitorum communis; (2) the sensibility of the radial three digits, especially the index finger; and (3) the intraoperative appearance, feel and electrophysiological status of the ipsilateral C7 nerve root. Transfer of the ipsilateral C7 nerve root to the upper trunk was implemented only when the following three tests were conducted, the criteria were met, and the clinical outcomes were assessed in eight patients with C5-C6 brachial plexus injuries. RESULTS: Patients were followed-up for an average of 90 ± 42 months. At the final follow-up, all eight patients achieved recovery of elbow flexion, with five and three patients scoring M4 and M3, respectively, according to the Medical Research Council scoring. The shoulder abduction range of motor recovery averaged 86 ± 47° (range, 30°-170°), whereas the shoulder external rotation averaged 51 ± 26° (range, 15°-90°). CONCLUSION: Ipsilateral C7 nerve transfer is a reliable and effective option for the functional reconstruction of the shoulder and elbow after C5-C6 brachial plexus injuries when the three prerequisites are met.


Assuntos
Plexo Braquial , Transferência de Nervo , Humanos , Transferência de Nervo/métodos , Adulto , Masculino , Plexo Braquial/lesões , Plexo Braquial/cirurgia , Feminino , Resultado do Tratamento , Pessoa de Meia-Idade , Raízes Nervosas Espinhais/cirurgia , Raízes Nervosas Espinhais/lesões , Adulto Jovem , Neuropatias do Plexo Braquial/cirurgia , Neuropatias do Plexo Braquial/fisiopatologia , Força Muscular/fisiologia , Recuperação de Função Fisiológica/fisiologia
16.
Ren Fail ; 46(1): 2332492, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38584135

RESUMO

Acute kidney injury (AKI) is associated with a high mortality rate. Pathologically, renal ischemia/reperfusion injury (RIRI) is one of the primary causes of AKI, and hypoxia-inducible factor (HIF)-1α may play a defensive role in RIRI. This study assessed the role of hypoxia-inducible factor 1α (HIF-1α)-mediated mitophagy in protection against RIRI in vitro and in vivo. The human tubular cell line HK-2 was used to assess hypoxia/reoxygenation (H/R)-induced mitophagy through different in vitro assays, including western blotting, immunofluorescence staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), and reactive oxygen species (ROS) measurement. Additionally, a rat RIRI model was established for evaluation by renal histopathology, renal Doppler ultrasound, and transmission electron microscopy to confirm the in vitro data. The selective HIF-1α inhibitor LW6 reduced H/R-induced mitophagy but increased H/R-induced apoptosis and ROS production. Moreover, H/R treatment enhanced expression of the FUN14 domain-containing 1 (FUNDC1) protein. Additionally, FUNDC1 overexpression reversed the effects of LW6 on the altered expression of light chain 3 (LC3) BII and voltage-dependent anion channels as well as blocked the effects of HIF-1α inhibition in cells. Pretreatment of the rat RIRI model with roxadustat, a novel oral HIF-1α inhibitor, led to decreased renal injury and apoptosis in vivo. In conclusion, the HIF-1α/FUNDC1 signaling pathway mediates H/R-promoted renal tubular cell mitophagy, whereas inhibition of this signaling pathway protects cells from mitophagy, thus aggravating apoptosis, and ROS production. Accordingly, roxadustat may protect against RIRI-related AKI.


Assuntos
Injúria Renal Aguda , Traumatismo por Reperfusão , Animais , Humanos , Ratos , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/prevenção & controle , Injúria Renal Aguda/metabolismo , Apoptose , Hipóxia/metabolismo , Hipóxia/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Isquemia , Rim/patologia , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais , Mitofagia , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais
17.
Nano Lett ; 23(16): 7552-7560, 2023 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-37494635

RESUMO

Zwitterionic polymers have emerged as promising trans-mucus nanocarriers due to their superior antifouling properties. However, for pH-sensitive zwitterionic polymers, the effect of the pH microenvironment on their trans-mucus fate remains unclear. In this work, we prepared a library of zwitterionic polydopamine-modified silica nanoparticles (SiNPs-PDA) with an isoelectric point of 5.6. Multiple-particle tracking showed that diffusion of SiNPs-PDA in mucus with a pH value of 5.6 was 3 times faster than that in mucus with pH value 3.0 or 7.0. Biophysical analysis found that the trans-mucus behavior of SiNPs-PDA was mediated by hydrophobic and electrostatic interactions and hydrogen bonding between mucin and the particles. Furthermore, the particle distribution in the stomach, intestine, and lung demonstrated the pH-mediated mucus penetration behavior of the SiNPs-PDA. This study reveals the pH-mediated mucus penetration behavior of zwitterionic nanomaterials, which provides rational design strategies for zwitterionic polymers as nanocarriers in various mucus microenvironments.


Assuntos
Portadores de Fármacos , Nanopartículas , Portadores de Fármacos/química , Dióxido de Silício/química , Polímeros/química , Nanopartículas/química , Muco , Concentração de Íons de Hidrogênio
18.
Int J Psychol ; 59(1): 30-38, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37700731

RESUMO

This study's objective was to examine the growth trajectories of freshman students' perceived stress and whether hostile attribution bias predicts the pattern of perceived stress change using latent growth analyses. A longitudinal dataset with fourth measurement points was gathered from a total of 1109 college students enrolled at a university in Guizhou Province in the first 3 months after college freshmen enrollment. The freshman students' levels of perceived stress tend to show a piecewise linear decline during the transition period, which manifests as a faster decline in the first stage (within the first month) than in the second stage (after the first month). Moreover, hostile attribution bias not only positively predicted the initial level of perceived stress but also positively predicted the slope of perceived stress in the first and second stages. In addition, there was a significant sex difference in the initial level of perceived stress where the initial level of perceived stress was higher in females than in males, but there was no significant sex difference in the rate of perceived stress decline. These results highlight the longitudinal relationship between hostile attribution bias and perceived stress and have implications for improving freshmen' college adaptation.


Assuntos
Percepção Social , Estudantes , Humanos , Masculino , Feminino , Estresse Psicológico , Universidades
19.
Angew Chem Int Ed Engl ; : e202405891, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769062

RESUMO

Organic solvent nanofiltration (OSN) plays important roles in pharmaceutical ingredients purification and solvent recovery. However, the low organic solvent permeance under cross-flow operation of OSN membrane hampers their industrial applications. Herein, we report the construction of coffee-ring structured membrane featuring high OSN permeance. A water-insoluble crystal monomer that dissolved in EtOH/H2O mixed solvent was designed to react with trimesoyl chloride via interfacial polymerization. Owing to the diffusion of EtOH to n-hexane, coffee-ring nanostructure on the support membrane appeared, which served as the template for construction of coffee-ring structured membrane. The optimal nanostructured membrane demonstrated 2.6-fold enhancement in the effective surface area with reduced membrane thickness. Resultantly, the membrane afforded a 2.7-fold enhancement in organic solvent permeance, e.g., ~13 LMH/bar for MeOH, without sacrificing the rejection ability. Moreover, due to the rigid monomer structure, the fabricated membrane shows distinctive running stability in active pharmaceutical ingredients purification and the ability for concentration of medicines.

20.
J Biol Chem ; 298(3): 101637, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35085555

RESUMO

Adaptation to nutrient deprivation depends on the activation of metabolic programs to use reserves of energy. When outside a host plant, second-stage juveniles (J2) of the root-knot nematode (Meloidogyne spp.), an important group of pests responsible for severe losses in the production of crops (e.g., rice, wheat, and tomato), are unable to acquire food. Although lipid hydrolysis has been observed in J2 nematodes, its role in fitness and the underlying mechanisms remain unknown. Using RNA-seq analysis, here, we demonstrated that in the absence of host plants, the pathway for the biosynthesis of polyunsaturated fatty acids was upregulated, thereby increasing the production of arachidonic acid in middle-stage J2 Meloidogyne incognita worms. We also found that arachidonic acid upregulated the expression of the transcription factor hlh-30b, which in turn induced lysosomal biogenesis. Lysosomes promoted lipid hydrolysis via a lysosomal lipase, LIPL-1. Furthermore, our data demonstrated that blockage of lysosomal lipolysis reduced both lifespan and locomotion of J2 worms. Strikingly, disturbance of lysosomal lipolysis resulted in a decline in infectivity of these juveniles on tomato roots. Our findings not only reveal the molecular mechanism of lipolysis in J2 worms but also suggest potential novel strategies for the management of root-knot nematode pests.


Assuntos
Solanum lycopersicum , Tylenchoidea , Animais , Ácidos Araquidônicos/metabolismo , Metabolismo dos Lipídeos , Lipólise , Solanum lycopersicum/parasitologia , Lisossomos , Tylenchoidea/metabolismo , Tylenchoidea/fisiologia
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