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1.
J Hazard Mater ; 448: 130880, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36736216

RESUMO

Cadmium (Cd) contamination is becoming a widespread environmental problem. However, the differential responsive mechanisms of Cd hyperaccumulator Solanum nigrum to low or high dose of Cd are not well documented. In this study, phenotypic and physiological analysis firstly suggested that the seedlings of S. nigrum showed slight leaf chlorosis symptoms under 25 µM Cd and severe inhibition on growth and photosynthesis under 100 µM Cd. Further proteomic analysis identified 105 differentially expressed proteins (DEPs) in the Cd-treated leaves. Under low dose of Cd stress, 47 DEPs are mainly involved in primary metabolic processes, while under high dose of Cd stress, 92 DEPs are mainly involved in photosynthesis, energy metabolism, production of phytochelatin and reactive oxygen species (ROS). Protein-protein interaction (PPI) network analysis of DEPs support above differential responses in the leaves of S. nigrum to low and high dose of Cd treatments. This work provides the differential responsive mechanisms in S. nigrum to low and high dose of Cd, and the theoretical foundation for the application of hyperaccumulating plants in the phytoremediation of Cd-contaminated soils.

2.
Chemosphere ; 318: 137967, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36731661

RESUMO

Decreases in microelement contents and increases in toxic element levels seriously affect crop growth and human health. Thus, improving the elemental content of food crops is an important environmental issue for enhancing crop production and quality. Previous research showed that metal tolerance protein 1 (MTP1) is localized at the vacuole membrane, wherein it mediates the translocation of heavy metal ions. Therefore, LmMTP1 was isolated from annual ryegrass (Lolium multiflorum). Real-time quantitative PCR analyses revealed LmMTP1 expression increased significantly in the roots after Zn, Co, and Cd treatments. Confocal microscopy images indicated LmMTP1 was localized at the vacuole membrane. The expression of LmMTP1 in transgenic yeast and rice resulted in increased Zn, Co, and Cd tolerance. The examination of heavy metal contents detected increases in the Zn and Co contents, but decreases in the Cd contents, of yeast and rice. Moreover, the grains of LmMTP1-expressing transgenic rice had higher Zn/Co contents and lower Cd contents than wild-type rice grains. These results imply that LmMTP1 influences Zn, Co, and Cd tolerance and accumulation. Furthermore, LmMTP1 might be a novel biofortification-related candidate gene useful for improving the storage of essential elements and eliminating toxic heavy metals from crops.

3.
Artigo em Inglês | MEDLINE | ID: mdl-36728053

RESUMO

BACKGROUND: Ankylosing spondylitis-related cervical spine fracture with neurologic impairment (ASCF-NI) is a rare but often lethal injury. Factors independently associated with survival after treatment remain poorly defined, and identifying patients who are likely to survive the injury remains challenging. QUESTIONS/PURPOSES: (1) What factors are independently associated with survival after treatment among patients with ASCF-NI? (2) Can a nomogram be developed that is sufficiently simple for clinicians to use that can identify patients who are the most likely to survive after injury? METHODS: This retrospective study was conducted based on a multi-institutional group of patients admitted and treated at one of 29 tertiary hospitals in China between March 1, 2003, and July 31, 2019. A total of 363 patients with a mean age of 53 ± 12 years were eventually included, 343 of whom were male. According to the National Household Registration Management System, 17% (61 of 363) died within 5 years of injury. Patients were treated using nonsurgical treatment or surgery, including procedures using the anterior approach, posterior approach, or combined anterior and posterior approaches. Indications for surgery included three-column injury, unstable fracture displacement, neurologic impairment or continuous progress, and intervertebral disc incarceration. By contrast, patients generally received nonsurgical treatment when they had a relatively stable fracture or medical conditions that did not tolerate surgery. Demographic, clinical, and treatment data were collected. The primary study goal was to identify which factors are independently associated with death within 5 years of injury, and the secondary goal was the development of a clinically applicable nomogram. We developed a multivariable Cox hazards regression model, and independent risk factors were defined by backward stepwise selection with the Akaike information criterion. We used these factors to create a nomogram using a multivariate Cox proportional hazards regression analysis. RESULTS: After controlling for potentially confounding variables, we found the following factors were independently associated with a lower likelihood of survival after injury: lower fracture site, more-severe peri-injury complications, poorer American Spinal Injury Association (ASIA) Impairment Scale, and treatment methods. We found that a C5 to C7 or T1 fracture (ref: C1 to C4 and 5; hazard ratio 1.7 [95% confidence interval 0.9 to 3.5]; p = 0.12), moderate peri-injury complications (ref: absence of or mild complications; HR 6.0 [95% CI 2.3 to 16.0]; p < 0.001), severe peri-injury complications (ref: absence of or mild complications; HR 30.0 [95% CI 11.5 to 78.3]; p < 0.001), ASIA Grade A (ref: ASIA Grade D; HR 2.8 [95% CI 1.1 to 7.0]; p = 0.03), anterior approach (ref: nonsurgical treatment; HR 0.5 [95% CI 0.2 to 1.0]; p = 0.04), posterior approach (ref: nonsurgical treatment; HR 0.4 [95% CI 0.2 to 0.8]; p = 0.006), and combined anterior and posterior approach (ref: nonsurgical treatment; HR 0.4 [95% CI 0.2 to 0.9]; p = 0.02) were associated with survival. Based on these factors, a nomogram was developed to predict the survival of patients with ASCF-NI after treatment. Tests revealed that the developed nomogram had good performance (C statistic of 0.91). CONCLUSION: The nomogram developed in this study will allow us to classify patients with different mortality risk levels into groups. This, coupled with the factors we identified, was independently associated with survival, and can be used to guide more appropriate treatment and care strategies for patients with ASCF-NI. LEVEL OF EVIDENCE: Level III, therapeutic study.

4.
Zhongguo Zhong Yao Za Zhi ; 48(1): 265-272, 2023 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-36725279

RESUMO

The present study explored the consistency of the content proportions of active components of Aurantii Fructus and analyzed the influencing factors based on three-dimensional multi-component analysis. A total of 839 Aurantii Fructus samples in 65 research articles were analyzed using the three-dimensional multi-component analysis mode. The content data of flavonoid components(naringin, hesperidin, neohesperidin, narirutin, and nobiletin), coumarin components(meranzin and gluconolactone), and alkaloid(synephrine) in 386 samples which met the criteria of 2020 edition of the Chinese Pharmacopoeia were extracted and adjusted to percentages, and the content ratios between components were calculated. The influencing factors of Aurantii Fructus quality were analyzed. The results showed content ratios of components as follows: neohesperidin∶naringin in the range of 0.4-1.2; narirutin∶naringin in the range of 0.02-0.16; hesperidin∶naringin in the range of 0.01-0.3; nobiletin∶naringin in the range of 0.000 588 3-0.069 68; synephrine∶naringin in the range of 0.02-0.042; gluconolactone∶naringin in the range of 0.001-0.01; meranzin∶naringin in the range of 0.000 4-0.035. The quality of Aurantii Fructus was closely related to the origin, variety, harvesting time, and processing method of medicinal materials. Harvesting time had a greater impact on the quality of Aurantii Fructus, and the origin and variety had a certain impact on the quality of Aurantii Fructus. The findings of this study indicated that the ratios between flavonoid components, flavonoids and coumarin components, and flavonoids and alkaloids fluctuated. The production base should optimize the varieties, harvesting period, and processing methods of Aurantii Fructus to provide a scientific basis for the production of high-quality Aurantii Fructus.


Assuntos
Citrus , Medicamentos de Ervas Chinesas , Flavonoides/análise , Frutas/química , Cumarínicos/análise , Cromatografia Líquida de Alta Pressão/métodos
5.
Proc Natl Acad Sci U S A ; 120(3): e2207080119, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36623198

RESUMO

The electrochemical conversion of waste nitrate (NO3-) to valuable ammonia (NH3) is an economical and environmentally friendly technology for sustainable NH3 production. It is beneficial for environmental nitrogen pollution management and is also an appealing alternative to the current Haber-Bosch process for NH3 production. However, owing to the competing hydrogen evolution reaction, it is necessary to design highly efficient and stable electrocatalysts with high selectivity. Herein, we report a rational design of Fe nanoparticles wrapped in N-doped carbon (Fe@N10-C) as a high NH3 selective and efficient electrocatalyst using a metal-organic framework precursor. We constructed a catalyst with new active sites by doping with nitrogen, which activated neighboring carbon atoms and enhanced metal-to-carbon electron transfer, resulting in high catalytic activity. These doped N sites play a key role in the NO3- electroreduction. As a result, the Fe@N10-C nanoparticles with optimal doping of N demonstrated remarkable performance, with a record-high NO3- removal capacity of 125.8 ± 0.5 mg N gcat-1 h-1 and nearly 100 % (99.7 ± 0.1%) selectivity. The catalyst also delivers an impressive NH3 production rate of 2647.7 µg h-1 cm-2 and high faradaic efficiency of 91.8 ± 0.1%. This work provides a new route for N-doped carbon-iron catalysis application and paves the way for addressing energy and environmental issues.

6.
Heliyon ; : e13119, 2023 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-36712914

RESUMO

Social distancing has been essential during the COVID-19 pandemic to slow the spread of the disease. Online learning ensures students can participate in learning activities while also maintaining a physical distance from other students. Although online learning was used to prevent the spread of COVID-19, the development of online learning has also been promoted. Here, we sought to explore the perceptions and responses of students to online learning during the pandemic using a cross-sectional study. Electronic questionnaire was used for data collection. Statistical analyses were performed for 1614 valid questionnaires and P < 0.05 was considered statistically significant. Overall, COVID-19 had more effect on female students, such as fear of COVID-19 (2.4 times higher than the number of male students) and length of time spent learning (H = 42.449, P < 0.05). However, the higher the students' grades were, the less the impact of COVID-19. For the style of lessons, all students would prefer shorter lessons (P < 0.05). Female and fifth-grade students were more prefer combined online and face-to-face learning, and male and freshmen students were more likely to prefer face-to-face learning after the pandemic. More than 50% of students thought the main advantage of online learning was convenience, with low efficiency being a disadvantage. The main factors negatively influencing online learning were eyestrain, poor network connections, and poor learning environments at home. In conclusion, synchronous online and face-to-face learning may become more common in future curricula, however the efficiency of online learning and the female students more attentions.

7.
SSM Popul Health ; 21: 101333, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36691488

RESUMO

Retirement has a heterogeneous impact depending on gender and occupation. This study aimed to analyze and evaluate the heterogeneity and potential mechanism of retirement on the biomedical risk factors for cardiovascular and metabolic diseases. Physical examination data from 2017 to 2020 were extracted from a hospital database in Shanghai. The fluctuation tendency of biomedical risk factor indicators for cardiovascular and metabolic diseases was evaluated by gender and occupation shortly after retirement using fuzzy regression discontinuity design and was analyzed for internal mechanism. Retirement had a significantly negative influence on body weight (ß = -3.943), body mass index (ß = -2.152), and diastolic blood pressure (ß = -5.180) in women working in public institutions or state-owned enterprises, but a positive influence on their blood glucose level (ß = 0.696). Retirement had a significantly positive effect on high-density lipoprotein in men (ß = 0.138), particularly those employed in private enterprises (ß = 0.339). The internal influencing mechanism of retirement showed that the health attention effect after retirement among women in government or public institutions on diastolic blood pressure reduction was better than that before retirement. The body weight, body mass index, and diastolic blood pressure of women in public institutions or state-owned enterprises were reduced at retirement; however, they were exposed to higher risks of elevated blood glucose level. Conversely, high-density lipoprotein level, which is protective against cardiovascular disease, was increased in men at retirement. Retirement has a heterogeneous effect on cardiovascular and metabolic health among people of different genders or occupational experiences. Retirees with low health awareness should be targeted for behavioral interventions and monitored conscientiously by health providers during retirement adaptation.

8.
ACS Omega ; 8(1): 1693-1701, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36643473

RESUMO

Multiple myeloma (MM), a plasma cell cancer in bone marrow, remains an incurable disease. Melphalan, an alkylating agent, is a conventional anticancer drug that is still widely used for MM treatment in clinics. However, melphalan-induced organ toxicity and side effects are common. In this study, we loaded melphalan into a liposomal capsule and constituted liposomal melphalan (liposomal MEL). Liposomal MEL particles were approximately 120 nm in size and stable in vitro. The liposomal particles could be effectively taken up by MM cells. In vitro cytotoxicity assays using MM cell lines and primary MM cells showed that liposomal MEL exhibited similar anti-MM activity compared to an equivalent amount of free melphalan (free MEL) compound. In animal models, liposomal particles had bone marrow enrichment and prolonged half-life in vivo. Liposomal MEL exposure resulted in less liver and colon organ toxicity than exposure to an equivalent amount of free MEL-treated mice. Importantly, liposomal MEL had potent anti-MM activity in vivo in a human MM xenograft mouse model. Overall, our findings suggested that liposome-encapsulated melphalan was an effective drug modification of the melphalan compound and showed promise in MM treatment.

9.
J Chem Inf Model ; 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36647267

RESUMO

Molecular descriptors are essential to quantitative structure activity/property relationship (QSAR/QSPR) models and machine learning models. Here we propose persistent path-spectral (PPS), PPS-based molecular descriptors, and PPS-based machine learning model for the prediction of the protein-ligand binding affinity, for the first time. For the graph, simplicial complex, and hypergraph representation of molecular structures and interactions, the path-Laplacian can be constructed and the derived path-spectral naturally gives a quantitative description of molecules. Further, by introducing the filtration process of the representation, the persistent path-spectral can be derived, which gives a multiscale characterization of molecules. Molecular descriptors from the persistent path-spectral attributes then are combined with the machine learning model, in particular, the gradient boosting tree, to form our PPS-ML model. We test our model on three most commonly used data sets, i.e., PDBbind-v2007, PDBbind-v2013, and PDBbind-v2016, and our model can achieve competitive results.

10.
Curr Pharm Des ; 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717995

RESUMO

BACKGROUND: Scutellarin exerts anticancer effects on diverse malignancies. However, its function in gastric cancer has not been explored. OBJECTIVE: This study aimed to examine the anticancer effect and molecular mechanism of scutellarin in gastric cancer. MATERIALS AND METHODS: Gastric cancer cells were treated with scutellarin and transfected with the Wnt1 overexpression plasmid. Cell viability, proliferation, toxicity, and apoptosis were determined by cell counting kit-8 (CCK-8), colony formation, lactate dehydrogenase (LDH) activity, TdT-mediated dUTP Nick-End Labeling (TUNEL), and flow cytometry assays. Expressions of apoptosis-related and Wnt/ß-catenin signaling pathway-related proteins were examined by western blot and quantitative reverse transcription polymerase chain reaction (qRT-PCR). RESULTS: Scutellarin concentration dependently restrained cell viability. Scutellarin (20 and 80 µmol/L) suppressed proliferation and promoted LDH release and apoptosis. Moreover, scutellarin elevated Bax and Cytochrome C levels but diminished the levels of Bcl-2, Wnt1, cytoplasmic ß-catenin, and basal cytoplasmic ß-catenin. However, the above-mentioned regulatory effects of scutellarin were all reversed by Wnt1 overexpression. CONCLUSION: Scutellarin suppressed gastric cancer cell proliferation and promoted apoptosis by inhibition of the Wnt/ß-catenin pathway.

11.
Sci Total Environ ; 869: 161875, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36709894

RESUMO

Aeration is of great importance in landfill remediation. However, most existing studies on aerobic waste degradation ignore the presence of landfill gases. In this study, gas characteristics during aerobic waste degradation in the presence of landfill gas in lab-scale lysimeters were investigated. Oxygen (O2) was intermittently injected into municipal solid waste. Changes in the gas concentration and reaction rate of methane (CH4), carbon dioxide (CO2), and O2 during the reaction process were monitored and calculated. The results showed that all reactions, including aerobic degradation, CH4 oxidation, and anaerobic waste degradation, occurred simultaneously during landfill aeration. The maximum O2 consumption rate was 0.013 mol day-1 kg-1 dry waste. CH4 production was stimulated after the O2 content was insufficient to sustain the aerobic environment. Higher CH4 production was likely attributed to the remaining substrate and biomass from dead aerobic microorganisms decomposed by growing anaerobic microorganisms. Based on the biochemical reaction and principle of mass conservation, a gas balance model during waste aeration was established to analyze the proportions of aerobic waste degradation, CH4 oxidation, and anaerobic waste degradation. The CH4 oxidation reaction was more advantageous than the aerobic waste degradation reaction during aeration. With an increase in gas injection times, the anaerobic reaction gradually weakened. The maximum proportion of CH4 oxidation reaction could achieve at 21.4 % during aeration, which is of great significance for the waste degradation reaction. The maximum proportion of aerobic waste degradation and the minimum proportion of anaerobic waste degradation were approximately 16.0 % and 74.2 %, respectively. The results show that landfill gas should be considered in the progress of landfill aeration. This study provides a novel approach for calculating the proportion of reactions during landfill aeration, which deepens the understanding of the reaction process and contributes to the design of aerobic landfill projects.

12.
Angew Chem Int Ed Engl ; : e202216083, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36594790

RESUMO

The electro-reforming of glycerol is an emerging technology of simultaneous hydrogen production and biomass valorization. However, its complex reaction network and limited catalyst tunability restrict the precise steering toward high selectivity. Herein, we incorporated the chelating phenanthrolines into the bulk nickel hydroxide and tuned the electronic properties by installing functional groups, yielding tunable selectivity toward formate (max 92.7 %) and oxalate (max 45.3 %) with almost linear correlation with the Hammett parameters. Further combinatory study of intermediate analysis and various spectroscopic techniques revealed the electronic effect of tailoring the valence band that balances between C-C cleavage and oxidation through the key glycolaldehyde intermediate. A two-electrode electro-reforming setup using the 5-nitro-1,10-phenanthroline-nickel hydroxide catalyst was further established to convert crude glycerol into pure H2 and isolable sodium oxalate with high efficiency.

13.
Sci Data ; 10(1): 35, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36653358

RESUMO

Data of the diabetes mellitus patients is essential in the study of diabetes management, especially when employing the data-driven machine learning methods into the management. To promote and facilitate the research in diabetes management, we have developed the ShanghaiT1DM and ShanghaiT2DM Datasets and made them publicly available for research purposes. This paper describes the datasets, which was acquired on Type 1 (n = 12) and Type 2 (n = 100) diabetic patients in Shanghai, China. The acquisition has been made in real-life conditions. The datasets contain the clinical characteristics, laboratory measurements and medications of the patients. Moreover, the continuous glucose monitoring readings with 3 to 14 days as a period together with the daily dietary information are also provided. The datasets can contribute to the development of data-driven algorithms/models and diabetes monitoring/managing technologies.


Assuntos
Automonitorização da Glicemia , Diabetes Mellitus , Humanos , Algoritmos , Glicemia , China , Aprendizado de Máquina
14.
Accid Anal Prev ; 181: 106950, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36592490

RESUMO

When transporting hazardous materials by rail, train types (unit train or manifest train) can influence derailment and release risks in several ways. Unit trains only experience risks on mainlines and when arriving at or departing from terminals, while manifest trains experience additional switching risks in yards. A comprehensive risk assessment methodology is needed to quantitively compare shipments with unit trains and manifest trains, considering both mainline and yard operations. To fulfill this research gap, this paper constructs event chains for line-haul risks, arrival/departure risks, and yard switching risks using various probabilistic models and finally determines expected casualties as the consequences of a potential train derailment and release incident. Five illustrative scenarios are designed to analyze the best and worst cases and compare the transportation risk differences between service options using unit trains and manifest trains. The comparison results indicate that placing all tank cars at the positions with the lowest probability of derailing and switching tank cars alone in classification yards could provide the lowest risk estimate given the same transportation demand.


Assuntos
Substâncias Perigosas , Ferrovias , Humanos , Acidentes de Trânsito , Medição de Risco , Meios de Transporte
15.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(1): 142-147, 2023 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-36647657

RESUMO

Objective: To prospectively explore the risk factors of suicide in patients with schizophrenia. Methods: Data on schizophrenia patients in Sichuan Province between 2006 and 2018 were obtained from the National Severe Mental Disorders Information System, and the Cox proportional hazards regression model was used to explore for risk factors for suicide in schizophrenia patients. Result: A total of 170006 patients with schizophrenia were included in the study. At the end of the follow-up period, 160570 patients were alive and 9436 died from various causes, 929 of which being suicide deaths, resulting in a suicide rate of 223.61/100, 000 person-years. The Cox proportional hazards regression model suggested that risk factors for suicide in patients with schizophrenia included poverty ( HR=1.20, 95% CI: 1.02-1.41), higher education level (primary school [ HR=1.32, 95% CI: 1.09-1.60], middle school [ HR=1.40, 95% CI: 1.14-1.73], high school and above [ HR=1.93, 95% CI: 1.49-2.52]) in comparison with illiteracy and semi-literacy, suicide attempts ( HR=2.70, 95% CI: 1.70-4.29), strict medication compliance ( HR=1.91, 95% CI: 1.66-2.20), history of antipsychotic drug therapy ( HR=1.42, 95% CI: 1.06-1.90), younger age group of patients of 46-60 ( HR=1.95, 95% CI: 1.60-2.39), 31-45 ( HR=3.61, 95% CI: 2.92-4.47), and 15-30 ( HR=12.37, 95% CI: 9.69-15.78) compared with the 61-90 age group, and doing agriculture jobs ( HR=1.36, 95% CI: 1.13-1.65). Conclusion: Young and middle-aged schizophrenia patients with higher education levels, especially those with a history of suicide attempts, are at high risk for suicide. Focused interventions should be directed at high-risk groups to reduce suicide deaths in patients with schizophrenia.


Assuntos
Esquizofrenia , Pessoa de Meia-Idade , Humanos , Esquizofrenia/epidemiologia , Tentativa de Suicídio , Fatores de Risco , China/epidemiologia
16.
Bioact Mater ; 24: 252-262, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36632501

RESUMO

Ventricular septal defect (VSD) is one of the commonest congenital heart diseases (CHDs). Current occluders for VSD treatment are mainly made of nitinol, which has the risk of nickel allergy, persistent myocardial abrasion and fatal arrythmia. Herein, a fully biodegradable polydioxanone (PDO) occluder equipped with a shape line and poly-l-lactic acid PLLA membranes is developed for VSD closure without the addition of metal marker. PDO occluder showed great mechanical strength, fatigue resistance, geometry fitness, biocompatibility and degradability. In a rat subcutaneous implantation model, PDO filaments significantly alleviated inflammation response, mitigated fibrosis and promoted endothelialization compared with nitinol. The safety and efficacy of PDO occluder were confirmed in a canine VSD model with 3-year follow-up, demonstrating the biodegradable PDO occluder could not only effectively repair VSD, induce cardiac remodeling but also address the complications associated with metal occluders. Furthermore, a pilot clinical trial with five VSD patients indicated that all the occluders were successfully implanted under the guidance of echocardiography and no adverse events occurred during the 3-month follow-up. Collectively, the fully bioresorbable PDO occluder is safe and effective for clinical VSD closure and holds great promise for the treatment of structural CHDs.

17.
Small ; : e2206487, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36642861

RESUMO

Cardiovascular disease is a leading cause of disability and death worldwide. Although the survival rate of patients with heart diseases can be improved with contemporary pharmacological treatments and surgical procedures, none of these therapies provide a significant improvement in cardiac repair and regeneration. Stem cell-based therapies are a promising approach for functional recovery of damaged myocardium. However, the available stem cells are difficult to differentiate into cardiomyocytes, which result in the extremely low transplantation efficiency. Nanomaterials are widely used to regulate the myocardial differentiation of stem cells, and play a very important role in cardiac tissue engineering. This study discusses the current status and limitations of stem cells and cell-derived exosomes/micro RNAs based cardiac therapy, describes the cardiac repair mechanism of nanomaterials, summarizes the recent advances in nanomaterials used in cardiac repair and regeneration, and evaluates the advantages and disadvantages of the relevant nanomaterials. Besides discussing the potential clinical applications of nanomaterials in cardiac therapy, the perspectives and challenges of nanomaterials used in stem cell-based cardiac repair and regeneration are also considered. Finally, new research directions in this field are proposed, and future research trends are highlighted.

18.
ACS Appl Mater Interfaces ; 15(4): 5974-5989, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36649205

RESUMO

The existence of lead ions seriously affects the quality of many metal products in metallurgical enterprises. Currently, the various methods of lead-ion removal tried by researchers will affect valuable metals in the removal process, thus resulting in low economic efficiency. In this study, a novel metal-organic framework adsorbent (UiO-FHD) which efficiently and selectively captures lead ions is developed by introducing multiple ligands. The maximum adsorption capacity of lead ions is 433.15 mg/g at pH 5. The adsorption process accords with the pseudo-second-order kinetic and the Langmuir isotherm models at room temperature. Thermodynamic experiments indicate that the removal of Pb(II) is facilitated by appropriate temperature reduction. The performance tests indicate that UiO-FHD maintains a high removal rate of 90.35% for Pb(II) after four consecutive adsorption-desorption cycles. The distribution coefficient of lead ions (26.7 L/g) shows that UiO-FHD has excellent selective adsorption for lead ions. It is revealed that the chelation of the sulfhydryl groups and the electrostatic interaction of the hydroxyl groups are the dominant factors to improve the removal rate of Pb(II) by density functional theory calculations. This study clarifies the value of self-designed novel organic ligands in metal-organic framework materials that selectively capture heavy-metal ions.

19.
ACS Appl Mater Interfaces ; 15(4): 6209-6216, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36654188

RESUMO

The integration of ferromagnetic/antiferromagnetic bilayers with exchange bias effect on flexible substrates is crucial for flexible spintronics. Here, the epitaxial Co/MnN bilayers are deposited on mica by facing-target sputtering. A large in-plane exchange bias field (HEB) of 1800 Oe with a coercive field (HC) of 2750 Oe appears in the Co (3.8 nm)/MnN (15.0 nm) bilayer at 5 K after field cooling from 300 to 5 K. Effective interfacial exchange energy Jeff of the Co/MnN bilayer is 0.83 erg/cm2. The strain-induced maximum increase of HEB and HC reaches 18% and 21%, respectively, in the Co(3.8 nm)/MnN(15.0 nm) bilayer. Strain-modulated HEB is attributed to the change of interfacial exchange coupling between Co and MnN layers. HEB is inversely proportional to Co thickness but independent of MnN thickness. The change of HEB is less than 5% after 100 bending cycles, indicating mechanical durability. The out-of-plane exchange bias also appears since Co spins are not fully reversed due to the strong pinning effect. Anisotropic magnetoresistance (AMR) and planar Hall resistance (Rxy) show obvious hysteresis due to HEB. Exchange bias-induced phase difference of AMR and Rxy almost remains unchanged at different bending strains. The results provide the basis for understanding the bending strain tailored exchange bias.

20.
Nat Commun ; 14(1): 61, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36599845

RESUMO

The multifunctional GSDMB protein is an important molecule in human immunity. The pyroptotic and bactericidal activity of GSDMB is a host response to infection by the bacterial pathogen Shigella flexneri, which employs the virulence effector IpaH7.8 to ubiquitinate and target GSDMB for proteasome-dependent degradation. Furthermore, IpaH7.8 selectively targets human but not mouse GSDMD, suggesting a non-canonical mechanism of substrate selection. Here, we report the crystal structure of GSDMB in complex with IpaH7.8. Together with biochemical and functional studies, we identify the potential membrane engagement sites of GSDMB, revealing general and unique features of gasdermin proteins in membrane recognition. We further illuminate how IpaH7.8 interacts with GSDMB, and delineate the mechanism by which IpaH7.8 ubiquitinates and suppresses GSDMB. Notably, guided by our structural model, we demonstrate that two residues in the α1-α2 loop make the mouse GSDMD invulnerable to IpaH7.8-mediated degradation. These findings provide insights into the versatile functions of GSDMB, which could open new avenues for therapeutic interventions for diseases, including cancers and bacterial infections.


Assuntos
Piroptose , Shigella flexneri , Humanos , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/fisiologia , Morte Celular , /fisiologia , Proteínas Citotóxicas Formadoras de Poros , Shigella flexneri/metabolismo , Shigella flexneri/patogenicidade
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