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1.
Bioresour Technol ; 368: 128321, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36379295

RESUMO

Bioconversion of sustainable feedstocks to commodity chemicals is considered as an effective solution for transforming the fossil-based economy into a carbon-neutral model. Here, the CO2-fixing bacterium Cupriavidus necator H16 was exploited for myo-inositol production from renewable substrates. First, by introducing the glucose transportation system, the glucose consumption route was established. Second, two key enzymes involved in myo-inositol biosynthesis were screened and evaluated. A myo-inositol-producing strain was constructed via overexpression of myo-inositol-3-phosphate synthase from Saccharomyces cerevisiae and inositol monophosphatase from Escherichia coli. Finally, carbon flux redirection was achieved through disruption of Entner-Doudoroff pathway and poly(3-hydroxybutyrate) synthesis pathway, resulting in a final myo-inositol production of 520.2, 1076.3 and 1054.8 mg/L from glucose, glycerol and CO2, respectively. The myo-inositol production level from CO2 achieved here set up the record. This study underlines the potential of C. necator to be utilized as microbial factory for upcycling the renewable feedstocks and CO2 to high-value biochemicals.


Assuntos
Cupriavidus necator , Cupriavidus necator/metabolismo , Dióxido de Carbono/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Ciclo do Carbono , Inositol , Glucose/metabolismo
2.
Bioact Mater ; 22: 291-311, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36263099

RESUMO

Flexible piezoelectrics realise the conversion between mechanical movements and electrical power by conformally attaching onto curvilinear surfaces, which are promising for energy harvesting of biomedical devices due to their sustainable body movements and/or deformations. Developing secondary functions of flexible piezoelectric energy harvesters is becoming increasingly significant in recent years via aiming at issues that cannot be addressed or mitigated by merely increasing piezoelectric efficiencies. These issues include loose interfacial contact and pucker generation by stretching, power shortage or instability induced by inadequate mechanical energy, and premature function degeneration or failure caused by fatigue fracture after cyclic deformations. Herein, the expedient secondary functions of flexible piezoelectrics to mitigate above issues are reviewed, including stretchability, hybrid energy harvesting, and self-healing. Efforts have been devoted to understanding the state-of-the-art strategies and their mechanisms of achieving secondary functions based on piezoelectric fundamentals. The link between structural characteristic and function performance is unravelled by providing insights into carefully selected progresses. The remaining challenges of developing secondary functions are proposed in the end with corresponding outlooks. The current work hopes to help and inspire future research in this promising field focusing on developing the secondary functions of flexible piezoelectric energy harvesters.

3.
Neural Regen Res ; 18(5): 1090-1098, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36254998

RESUMO

Neural progenitor cells (NPCs) capable of self-renewal and differentiation into neural cell lineages offer broad prospects for cell therapy for neurodegenerative diseases. However, cell therapy based on NPC transplantation is limited by the inability to acquire sufficient quantities of NPCs. Previous studies have found that a chemical cocktail of valproic acid, CHIR99021, and Repsox (VCR) promotes mouse fibroblasts to differentiate into NPCs under hypoxic conditions. Therefore, we used VCR (0.5 mM valproic acid, 3 µM CHIR99021, and 1 µM Repsox) to induce the reprogramming of rat embryonic fibroblasts into NPCs under a hypoxic condition (5%). These NPCs exhibited typical neurosphere-like structures that can express NPC markers, such as Nestin, SRY-box transcription factor 2, and paired box 6 (Pax6), and could also differentiate into multiple types of functional neurons and astrocytes in vitro. They had similar gene expression profiles to those of rat brain-derived neural stem cells. Subsequently, the chemically-induced NPCs (ciNPCs) were stereotactically transplanted into the substantia nigra of 6-hydroxydopamine-lesioned parkinsonian rats. We found that the ciNPCs exhibited long-term survival, migrated long distances, and differentiated into multiple types of functional neurons and glial cells in vivo. Moreover, the parkinsonian behavioral defects of the parkinsonian model rats grafted with ciNPCs showed remarkable functional recovery. These findings suggest that rat fibroblasts can be directly transformed into NPCs using a chemical cocktail of VCR without introducing exogenous factors, which may be an attractive donor material for transplantation therapy for Parkinson's disease.

4.
Oncol Rep ; 49(1)2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36382661

RESUMO

Lung cancer (LC) is the leading cause of cancer­related death, with high incidence and mortality rate. Early diagnosis and treatment of LC are imperative to improve the 5­year survival rate for patients with LC. In recent years, miRNAs as promising biomarkers with high sensitivity and specificity for LC have been studied increasingly. In LC regulatory networks, miRNAs play crucial roles in the occurrence, development and metastasis of non­small cell lung cancer (NSCLC), such as oncogenic factors, tumor suppressors and regulators. Dysfunctional miRNAs perform tumor­suppressive or oncogenic functions in the regulation of cell proliferation, invasion, apoptosis, cell cycle disorder and angiogenesis by negatively regulating target genes. In the present review, the biological process of miRNAs was firstly summarized and recent advances in the mechanism of miRNAs involved in tumor formation and development were described. In addition, the present review concentrated on the latest findings on the miRNAs related with circulating free and extracellular vesicles in the early diagnosis of NSCLC. Additionally, the diagnostic performances of circulating free and extracellular vesicles­associated miRNAs in NSCLC were contrasted. Owing to the increased stability and wide­ranging practical applicability, miRNA may be one promising biomarker for NSCLC diagnosis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Humanos , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Biomarcadores Tumorais/genética , Carcinogênese/genética , Regulação Neoplásica da Expressão Gênica
5.
J Comp Neurol ; 531(1): 149-169, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36222577

RESUMO

The Fragile X mental retardation protein (FMRP) is an mRNA binding protein that is essential for neural circuit assembly and synaptic plasticity. Loss of functional FMRP leads to Fragile X syndrome (FXS), a neurodevelopmental disorder characterized by sensory dysfunction including abnormal auditory processing. While the central mechanisms of FMRP regulation have been studied in the brain, whether FMRP is expressed in the auditory periphery and how it develops and functions remains unknown. In this study, we characterized the spatiotemporal distribution pattern of FMRP immunoreactivity in the inner ear of mice, rats, gerbils, and chickens. Across species, FMRP was expressed in hair cells and supporting cells, with a particularly high level in immature hair cells during the prehearing period. Interestingly, the distribution of cytoplasmic FMRP displayed an age-dependent translocation in hair cells, and this feature was conserved across species. In the auditory ganglion (AG), FMRP immunoreactivity was detected in neuronal cell bodies as well as their peripheral and central processes. Distinct from hair cells, FMRP intensity in AG neurons was high both during development and after maturation. Additionally, FMRP was evident in mature glial cells surrounding AG neurons. Together, these observations demonstrate distinct developmental trajectories across cell types in the auditory periphery. Given the importance of peripheral inputs to the maturation of auditory circuits, these findings implicate involvement of FMRP in inner ear development as well as a potential contribution of periphery FMRP to the generation of auditory dysfunction in FXS.


Assuntos
Orelha Interna , Síndrome do Cromossomo X Frágil , Animais , Camundongos , Ratos , Proteína do X Frágil de Retardo Mental/genética , Proteína do X Frágil de Retardo Mental/metabolismo , Gerbillinae , Galinhas/metabolismo , Síndrome do Cromossomo X Frágil/genética , Orelha Interna/metabolismo
6.
J Environ Manage ; 325(Pt B): 116587, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36323118

RESUMO

In this study, magnetic CoMoO4/CoFe2O4 (CMO/CFO) nanospheres with a core-shell structure were synthesized via two-step hydrothermal methods. The obtained particles were employed as catalysts to activate peroxymonosulfate (PMS) and degrade methylene blue (MB). The physico-chemical characterizations of the synthesized CMO/CFO showed that the CMO shell contributed to the enhancement of redox conversion and the increase in the concentration of oxygen vacancies (OVs). By examining reactive oxygen species (ROS) in the CMO/CFO/PMS system, the MB degradation was dominated by a non-radical pathway, and 1O2 was identified as the most abundant ROS. Besides, the CMO/CFO exhibited faster reaction kinetics than the pristine CFO. Moreover, the magnetic properties guaranteed the recycling and reuse of CMO/CFO, and the removal rate of MB was maintained at ∼94% after continuous use five times. Both the tolerance to SO42-and the wide pH range where the material is applicable make it a promising catalyst for dyeing wastewater treatment.


Assuntos
Azul de Metileno , Peróxidos , Azul de Metileno/química , Espécies Reativas de Oxigênio , Peróxidos/química , Fenômenos Magnéticos
7.
Chemosphere ; 311(Pt 1): 137073, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36332733

RESUMO

Runoff loss of nitrogen from paddy fields has received increasing attention in recent years. Duckweed is an aquatic plant frequently found in paddy fields. In this study, the effects of duckweed (Lemna minor L.) in floodwater on aqueous nitrogen losses from paddy fields were systematically investigated. Results demonstrated that the growth of duckweed decreased total nitrogen concentrations in floodwater and nitrogen runoff loss from paddy fields by 16.7%-18.3% and 11.2%-13.6%, respectively. Moreover, compared with NO3-, NH4+ was preferentially removed by duckweed. 15N isotope tracer experiments revealed that the growth and decomposition of duckweed acted as a "buffer" against the nitrogen variation in floodwater after fertilization. During the growth of duckweed, leaves were found to be the principal organ to assimilate NH4+ and release NO3- by using non-invasive micro-test technology. Duckweed degradation increased the content of hydrophobic acids and marine humic-like substances in floodwater, which promoted the migration of nitrogen from floodwater to soil. Redundancy analysis and structural equation models further illustrated that pH and temperature variation in floodwater caused by duckweed played a greater role in aqueous nitrogen loss reduction than the nitrogen accumulation in duckweed. This study suggested that the growth of duckweed in paddy fields was an effective supplementary method for controlling aqueous nitrogen loss during agricultural production.


Assuntos
Araceae , Oryza , Nitrogênio/análise , Fertilizantes/análise , Oryza/metabolismo , Agricultura/métodos , Araceae/metabolismo , Água/química , Fertilização
8.
J Environ Sci (China) ; 125: 185-193, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36375904

RESUMO

It is extremely important to analyze the contaminative behaviors of Perfluoroalkyl acids (PFAAs) due to their serious threats to urban environments which are closely related to humans. Current study aimed to explore the distribution, source apportionment and ecological risk assessment of PFAAs in surface water from Shijiazhuang, China. The concentrations of ∑PFAAs ranged from 19.5 to 125.9 ng/L in the investigation area. Perfluorobutanesulfonic acid (PFBS) and perfluoropentanoic acid (PFPeA) were the predominant contaminants (mean value: 14.3 ng/L and 16.6 ng/L, respectively). The distribution of PFAAs according to geospatial analysis and hierarchical clustering analysis (HCA) showed that higher levels of ∑PFAAs were detected in the southern surface water of Shijiazhuang and there was a stepwise decrease from the wet season to the dry season. Furthermore, based on source apportionment, the dominant potential sources were found to be wastewater treatment plant (WWTP) effluents and industrial discharge. The risk quotients (RQs) revealed low ecological risks of all PFAAs for aquatic organisms in Shijiazhuang surface water. Collectively, this study provided basic data for regulatory strategies for controlling PFAA pollutions in urban surface water.


Assuntos
Ácidos Alcanossulfônicos , Fluorcarbonetos , Poluentes Químicos da Água , Humanos , Fluorcarbonetos/análise , Rios , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Água/análise , China , Ácidos Alcanossulfônicos/análise
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 285: 121867, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36108408

RESUMO

Fluorescent material exhibiting aggregation-induced emission (AIE) has demonstrated to be a facile and effective method to detect 2,4,6-trinitrophenol (TNP) due to its excellent features. In this study, a novel diphenyl imidazole-based fluorescent material (DINP) was successfully synthesized via a facile method. Fluorescence spectra showed that DINP had a typical AIE effect in DMSO/water solution, and the fluorescence emission was effectively quenched by TNP without being affected by other explosives. The Stern-Volmer quenching constant of 2.70 × 105 M-1 and detection limit of 7.2 × 10-8 M demonstrated that the DINP aggregates could serve as potential chemosensor for TNP detection. The mechanism behind the quenching of fluorescence could be ascribed to the formation of ground state complex. In addition, fluorescent test strips and TLC plate prepared with the aggregates provided an easy and low cost method for TNP detection in the aqueous solution. Especially, DINP was applied to quantitatively detect the content of TNP in real water samples. Furthermore, the aggregates exhibited good selective adsorptive performance to rhodamine B dye in aqueous solution with high adsorption efficiency of 98 % in a few minutes.


Assuntos
Corantes Fluorescentes , Água , Espectrometria de Fluorescência/métodos , Imidazóis
10.
J Affect Disord ; 320: 319-329, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36183818

RESUMO

BACKGROUND: Social and interpersonal context are associated with the onset and persistence of psychiatric disorders. We compared the effects of short-term interpersonal psychotherapy (IPT) on weight loss, binge eating behaviors, and depressive symptoms against cognitive-behavioral therapy (CBT), health education (HE), and behavioral weight loss (BWL). METHODS: We searched until May 28th, 2022 following databases: PubMed, CINAHL, Science Direct, Web of Science, EMBASE, and Scopus. Articles on parallel randomized clinical trials were included. Outcomes were body mass index (BMI), binge days (bulimic episode), and depressive symptoms. These outcomes were self-reported or measured with specific scales (BMI) or instrument (depressive symptoms). RESULTS: The initial search retrieved 820 articles, a total of 10 studies met the eligibility criteria, and seven were included in the meta-analysis. Participants with overweight/obesity were women (62-100 %), aged between 11 and 50 years. There was a trivial to small effect on BMI favoring IPT over other interventions (standardized mean difference [SMD] = -0.10; 95%CI: -0.27 to 0.07, I2 = 0 %), especially when compared to health education (SMD = -0.21; 95%CI: -0.54 to 0.12, I2 = 0 %); no effect on number of binge days (SMD = -0.09; 95%CI: -0.30 to 0.11, I2 = 0 %); and a small effect on depressive symptoms (SMD = -0.25, 95%CI = -0.50 to 0.00, I2 = 0 %). LIMITATIONS: Small number of studies, the discrepancy in age cohorts, and racial diversity. Psychotherapeutic protocols and assessment tools had to be adapted across studies. CONCLUSIONS: Patients with overweight/obesity and depression had some benefit from IPT when compared with other interventions. In view of existing evidence, an IPT program adapted to obesity could help to achieve reliable and long-term effects.


Assuntos
Psicoterapia Interpessoal , Psicoterapia , Humanos , Feminino , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Masculino , Psicoterapia/métodos , Sobrepeso/terapia , Obesidade/terapia , Obesidade/psicologia , Redução de Peso
11.
Medicine (Baltimore) ; 101(47): e31678, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36451432

RESUMO

RATIONALE: 5-Fluorouracil (5-FU) and actinomycin D (ActD) are often used in chemotherapy for various cancers. Side effects are more common in bone marrow suppression, liver function impairment, and gastrointestinal responses. Skin effects are rare and easy to be ignored by doctors and patients, which can lead to life-threatening consequence. PATIENT CONCERNS: We reported a 45-year-old woman patient developed skin erythema and fingernail belt in chemotherapy of 5-FU and ActD. DIAGNOSIS: Erythema multiforme drug eruption. INTERVENTIONS: Laboratory tests including blood and urine routine, liver and kidney function, electrolytes and coagulation function and close observation. OUTCOMES: The rash was gone and the nail change returned. LESSONS: Delays in diagnosis or treatment may lead to serious consequence. We should pay attention to the dosage of 5-FU and ActD, monitor adverse reactions strictly, to reduce occurrence of skin malignant events.


Assuntos
Erupção por Droga , Eritema Multiforme , Mola Hidatiforme Invasiva , Neoplasias Uterinas , Feminino , Gravidez , Humanos , Pessoa de Meia-Idade , Dactinomicina/efeitos adversos , Fluoruracila/efeitos adversos , Eritema Multiforme/induzido quimicamente , Erupção por Droga/etiologia
12.
Food Chem ; 406: 135068, 2022 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-36462358

RESUMO

This study aimed to investigate the effects of dynamic high-pressure homogenization (DHPH), dynamic high-pressure microfluidization (DHPM), and wet media milling (WMM) processes on the particle size, microstructure, triple helix structure, wettability and suspension stability of insoluble undenatured type II collagen (IUC-II). The structural and powdery properties were regulated by different processes and parameters. By contrast, WMM-treated IUC-II showed smallest particle size (15.70 µm), highest wetting rate (216.94 mm/h) and best suspension stability. However, individual mechanical processes caused partial disruption of IUC-II triple helix structure. Low-acyl gellan gum (LAGG) could bind to IUC-II through hydrogen bonds and hydrophobic interactions, which protected the triple helix structure and further enhanced powdery properties of IUC-II treated by WMM process, but restrained the soluble transition during digestion. These results demonstrated that WMM process was more suitable for enhancing powdery properties of IUC-II, while the triple helix structure of IUC-II could be effectively protected by LAGG.

13.
Endocrine ; 2022 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-36462146

RESUMO

PURPOSE: To evaluate the application value of a generally trained artificial intelligence (AI) automatic diagnosis system in the malignancy diagnosis of rare thyroid carcinomas, such as follicular thyroid carcinoma, medullary thyroid carcinoma, primary thyroid lymphoma and anaplastic thyroid carcinoma and compare the diagnostic performance with radiologists of different experience levels. METHODS: We retrospectively studied 342 patients with 378 thyroid nodules that included 196 rare malignant nodules by using postoperative pathology as the gold standard, and compared the diagnostic performances of three radiologists (one junior, one mid-level, one senior) and that of AI automatic diagnosis system. RESULTS: The accuracy of the AI system in malignancy diagnosis was 0.825, which was significantly higher than that of all three radiologists and higher than the best radiologist in this study by a margin of 0.097 with P-value of 2.252 × 10-16. The mid-level radiologist and senior radiologist had higher sensitivity (0.857 and 0.959) than that of the AI system (0.847) at the cost of having much lower specificity (0.533, 0.478 versus 0.802). The junior radiologist showed relatively balanced sensitivity and specificity (0.816 and 0.549) but both were lower than that of the AI system. CONCLUSIONS: The generally trained AI automatic diagnosis system showed high accuracy in the differential diagnosis of begin nodules and rare malignancy nodules. It may assist radiologists for screening of rare malignancy nodules that even senior radiologists are not acquainted with.

14.
Theranostics ; 12(18): 7729-7744, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36451853

RESUMO

Rationale: IgA can induce activation of neutrophils which are the most abundant cell type in blood, but the development of IgA as therapeutic has been confounded by its short half-life and a weak ability to recruit NK cells as effector cells. Therefore, we generated an X-shaped antibody (X-body) based on the principle of molecular self-assembly that combines the activities of both IgG and IgA, which can effectively recruit and activate NK cells, macrophages, and neutrophils to kill tumor cells. Methods: X-body was generated by using a self-assembly strategy. The affinity of the X-body with the antigen and Fc receptors was tested by surface plasmon resonance. The shape of X-body was examined using negative staining transmission electron microscopy. The tumor cell killing activity of X-body was assessed in vitro and in multiple syngeneic mouse models. To explore the mechanism of X-body, tumor-infiltrating immune cells were analyzed by single-cell RNA-seq and flow cytometry. The dependence of neutrophil, macrophage, and NK cells for the X-body efficacy was confirmed by in vivo depletion of immune cell subsets. Results: The X-body versions of rituximab and trastuzumab combined the full spectrum activity of IgG and IgA and recruited NK cells, macrophages, and neutrophils as effector cells for eradication of tumor cells. Treatment with anti-hCD20 and anti-hHER2 X-bodies leads to a greater reduction in tumor burden in tumor-bearing mice compared with the IgA or IgG counterpart, and no obvious adverse effect is observed upon X-body treatment. Moreover, the X-body has a serum half-life and drug stability comparable to IgG. Conclusions: The X-body, as a myeloid-cell-centered therapeutic strategy, holds promise for the development of more effective cancer-targeting therapies than the current state of the art.


Assuntos
Células Matadoras Naturais , Neoplasias , Camundongos , Animais , Neoplasias/terapia , Contagem de Leucócitos , Imunoglobulina A , Imunoglobulina G
15.
Zhen Ci Yan Jiu ; 47(11): 993-8, 2022 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-36453676

RESUMO

OBJECTIVE: To observe the effect of early electroacupuncture(EA) intervention on ionized calcium binding adapter molecule 1 (Iba-1), tyrosine hydroxylase (TH) and tumor necrosis factor-α (TNF-α) in Parkinson's disease (PD) mice, so as to explore its neuroinflammation mechanism in treating PD. METHODS: A total of 24 male C57BL/6J mice (9 weeks old) were randomly divided into control, model and EA groups, with 8 mice in each group. The PD model was established by long-term low dose subcutaneous injection of rotenone. Started at the same time with modeling, EA (2 Hz/100 Hz, 1 mA) was applied to "Shenting"(GV24), bilateral "Tianshu"(LI11), "Quchi"(ST25), and "Shangjuxu"(ST37) for 15 min, once a day for 8 weeks. The motor function was assessed by rotorod test and step length test. The expression levels of Iba-1 and TH proteins in substantia nigra pars compacta (SNpc) was detected by Western blot and immunohistochemistry. The expression level of TNF-α protein in colon tissue was examined by Western blot and immunofluorescence staining. RESULTS: Compared with the control group, the fall latency shortened at 4, 6, and 8 weeks after modeling (P<0.01) and the step length of hind limbs shortened at 5 and 7 weeks after modeling (P<0.01), the expression levels of Iba-1 in SNpc and TNF-α in colon tissue were increased (P<0.01), and the expression level of TH in SNpc was decreased (P<0.01) in the model group. Compared with the model group, the fall latency prolonged at 6 and 8 weeks after modeling (P<0.01) and the step length of hind limbs prolonged at 5 and 7 weeks after modeling (P<0.01), the expression levels of Iba-1 in SNpc and TNF-α in colon tissue were decreased (P<0.01, P<0.05), and the expression level of TH in SNpc was increased (P<0.05, P<0.01) in the EA group. CONCLUSION: Early EA intervention can delay the occurring time of motor disfunction, alleviated the loss of substantia nigra dopaminergic neurons, and exerted a good neuroprotective effect on the degenerative changes in rotenone-induced PD mice, which may be related to its effects in alleviating the intestinal inflammation, inhibiting the activation of microglia, thereby reducing the neuroinflammation.


Assuntos
Eletroacupuntura , Doença de Parkinson , Masculino , Camundongos , Animais , Camundongos Endogâmicos C57BL , Fator de Necrose Tumoral alfa/genética , Doença de Parkinson/genética , Doença de Parkinson/terapia , Rotenona , Tirosina 3-Mono-Oxigenase/genética
16.
Nanomaterials (Basel) ; 12(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36364635

RESUMO

Converting carbon dioxide into high-value-added formic acid as a basic raw material for the chemical industry via an electrochemical process under ambient conditions not only alleviates greenhouse gas effects but also contributes to effective carbon cycles. Unfortunately, the most commonly used Pd-based catalysts can be easily poisoned by the in situ formed minor byproduct CO during the carbon dioxide reduction reaction (CRR) process. Herein, we report a facile method to synthesize highly uniformed PdAg alloys with tunable morphologies and electrocatalytic performance via a simple liquid synthesis approach. By tuning the molar ratio of the Ag+ and Pd2+ precursors, the morphologies, composition, and electrocatalytic activities of the obtained materials were well-regulated, which was characterized by TEM, XPS, XRD, as well as electrocatalytic measurements. The CRR results showed that the as-obtained Pd3Ag exhibited the highest performance among the five samples, with a faradic efficient (FE) of 96% for formic acid at -0.2 V (vs. reference hydrogen electrode (RHE)) and superior stability without current density decrease. The enhanced ability to adsorb and activate CO2 molecules, higher resistance to CO, and a faster electronic transfer speed resulting from the alloyed PdAg nanostructure worked together to make great contributions to the improvement of the CRR performance. These findings may provide a new feasible route toward the rational design and synthesis of alloy catalysts with high stability and selectivity for clean energy storage and conversion in the future.

17.
Plants (Basel) ; 11(21)2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36365447

RESUMO

Alfalfa (Medicago sativa L.) is an important forage crop, and its productivity is severely affected by salt stress. Although proline is a compatible osmolyte that plays an important role in regulating plant abiotic stress resistance, the basic mechanism of proline requires further clarification regarding the effect of proline in mitigating the harmful effects of salinity. Here, we investigate the protective effects and regulatory mechanisms of proline on salt tolerance of alfalfa. The results show that exogenous proline obviously promotes seed germination and seedling growth of salt-stressed alfalfa. Salt stress results in stunted plant growth, while proline application alleviates this phenomenon by increasing photosynthetic capacity and antioxidant enzyme activities and decreasing cell membrane damage and reactive oxygen species (ROS) accumulation. Plants with proline treatment maintain a better K+/Na+ ratio by reducing Na+ accumulation and increasing K+ content under salt stress. Additionally, proline induces the expression of genes related to antioxidant biosynthesis (Cu/Zn-SOD and APX) and ion homeostasis (SOS1, HKT1, and NHX1) under salt stress conditions. Proline metabolism is mainly regulated by ornithine-δ-aminotransferase (OAT) and proline dehydrogenase (ProDH) activities and their transcription levels, with the proline-treated plants displaying an increase in proline content under salt stress. In addition, OAT activity in the ornithine (Orn) pathway rather than Δ1-pyrroline-5-carboxylate synthetase (P5CS) activity in the glutamate (Glu) pathway is strongly increased under salt stress, made evident by the sharp increase in the expression level of the OAT gene compared to P5CS1 and P5CS2. Our study provides new insight into how exogenous proline improves salt tolerance in plants and that it might be used as a significant practical strategy for cultivating salt-tolerant alfalfa.

18.
Polymers (Basel) ; 14(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36365650

RESUMO

This paper provides a comprehensive understanding of the amplitude- and frequency-dependent characteristics of rubber springs. The dynamic nonlinear inelasticity of rubber is a key academic problem for continuum mechanics and a bottleneck problem for the practical use of rubber structures. Despite intensive efforts witnessed in industrial applications, it still demands an unambiguous constitutive model for dynamic nonlinear inelasticity, which is known as the Payne effect. To this end, three types of rubber springs (shear-type (ST), compression-type (CT) and shear-compression-combination-type (SCCT)) were tested with amplitude and frequency sweeps in different conditions. We investigated and present changes in dynamic stiffness and loss factor with amplitude, frequency and the hysteresis loops of different rubber springs. We also propose a hypothesis and research strategy to study a constitutive model involving multiple factors of hyperelasticity, the Mullins effect, viscoelasticity and the Payne effect, which we hope will provide new ideas for the establishment of a constitutive equation.

19.
Acta Biomater ; 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36328127

RESUMO

Transition-metal chalcogenides, such as noble metal chalcogenides, hold tremendous potential as efficient agents for photo-induced cancer theranostics due to their unique physicochemical properties. However, a critical bottleneck still lies in exploring simple and controllable methods to synthesize noble metal chalcogenides especially PtS for in vivo photo-induced cancer imaging and simultaneous therapy. Herein, we proposed the albumin-templated synthesis of size-controllable platinum (II) sulfide nanodots (PtS-NDs) for multimodal cancer imaging and potent photothermal therapy. PtS-NDs were precisely synthesized with a tunable size ranging from 2.1 nm to 4.5 nm through a thermodynamically controlled growth inside albumin nanocages. PtS-NDs yielded significant near-infrared (NIR) absorbance and outstanding photothermal conversion under NIR laser irradiation, as well as effective resistance to photobleaching, thereby generating remarkable in vivo photoacoustic signals and distinct hyperthermia at tumor site. Moreover, these nanodots possessed efficient cellular uptake and tumor targeting capabilities in a size-dependent manner, thus leading to controllable diagnostic and thermo-therapeutic efficacy. Specifically, PtS-NDs with core diameter of 4.5 nm displayed preferable in vivo photoacoustic and CT imaging with high sensitivity, spatially and anatomically enhanced imaging contrast, together with hyperthermia mediated tumor ablation. Thus, the albumin-templated biomimetic synthesis provided an insightful strategy on fabricating theranostic PtS-NDs for potential clinical applications. STATEMENT OF SIGNIFICANCE: Noble metal chalcogenides especially PtS are of particular importance in the field of precise nanomedicine to improve both accuracy of cancer diagnosis and efficiency of tumor treatment. However, the intensively preclinical investigation of PtS was limited due to the lack of simple and controllable synthetic methods. Here, we report an albumin-templated biomineralization synthesis of platinum (II) sulfide nanodots (PtS-NDs). Specifically, albumin-templated biomineralization of PtS-NDs was induced by the electrostatic interactions between albumin and Pt2+, followed by the nucleation and growth inside the albumin nanocages. The resulting PtS-NDs showed good dispersibility and biosafety, as well as size-dependent photophysical properties and biological behaviors. Therefore, albumin-based biomineralization is a promising and safe strategy to facilely fabricate Pt-based chalcogenide for tumor theranostics.

20.
Soc Sci Med ; 314: 115398, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36327631

RESUMO

RATIONALE: Health misinformation poses a significant threat to public health. Understanding why people believe health misinformation and who is at risk is crucial for developing effective interventions to reduce the harmful impact of misinformation. APPROACH: We conducted a systematic review of published empirical research that examined individual differences in susceptibility to health misinformation, focusing on the psychological, demographic, and behavioral correlates of health misinformation susceptibility. To guide our review on psychological correlates, we developed an integrative psychological model of susceptibility to health misinformation based on one's ability and motivation to reason. RESULTS: We identified 47 publications (61 empirical studies) that met our criteria. Our review suggests that subject knowledge, literacy and numeracy, analytical thinking (vs. intuitive thinking), and trust in science confer strong resistance to health misinformation, whereas conspiracy thinking, religiosity, conservative ideology, and conservative party identification are associated with more susceptibility to health misinformation. Demographically, older age and higher educational attainment predict less susceptibility to health misinformation, whereas racial minority status is associated with greater susceptibility. Behaviorally, relying on health professionals or scientists as information sources predicts less susceptibility to health misinformation, whereas social media use is associated with greater susceptibility. CONCLUSIONS: Susceptibility to health misinformation is driven by multiple psychological processes. Interventions for reducing the spread and impact of health misinformation should be tailored to the psychological mechanism underlying susceptibility to health misinformation. Limited resources should be used to support interventions targeted at individuals at risk.


Assuntos
Individualidade , Mídias Sociais , Humanos , Alfabetização , Confiança , Pessoal de Saúde
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