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1.
Front Med (Lausanne) ; 11: 1404479, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38994335

RESUMO

Background: The incidence of cardiac arrest (CA) during percutaneous coronary intervention (PCI) is relatively rare. However, when it does occur, the mortality rate is extremely high. Extracorporeal cardiopulmonary resuscitation (ECPR) has shown promising survival rates for in-hospital cardiac arrests (IHCA), with low-flow time being an independent prognostic factor for CA. However, there is no definitive answer on how to reduce low-flow time. Methods: This retrospective study, conducted at a single center, included 39 patients who underwent ECPR during PCI between January 2016 and December 2022. The patients were divided into two cohorts based on whether standby extracorporeal membrane oxygenation (ECMO) was utilized during PCI: standby ECPR (SBE) (n = 13) and extemporaneous ECPR (EE) (n = 26). We compared the 30-day mortality rates between these two cohorts and investigated factors associated with survival. Results: Compared to the EE cohort, the SBE cohort showed significantly lower low-flow time (P < 0.01), ECMO operation time (P < 0.01), and a lower incidence of acute kidney injury (AKI) (P = 0.017), as well as peak lactate (P < 0.01). Stand-by ECMO was associated with improved 30-day survival (p = 0.036), while prolonged low-flow time (p = 0.004) and a higher SYNTAX II score (p = 0.062) predicted death at 30 days. Conclusions: Standby ECMO can provide significant benefits for patients who undergo ECPR for CA during PCI. It is a viable option for high-risk PCI cases and may enhance the overall prognosis. The low-flow time remains a critical determinant of survival.

2.
Sci Data ; 11(1): 726, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956094

RESUMO

High-resolution oasis maps are imperative for understanding ecological and socio-economic development of arid regions. However, due to the late establishment and relatively niche nature of the oasis discipline, there are no high-precision datasets related to oases in the world to date. To fill this gap, detailed visual interpretation of remote sensing images on Google Earth Professional or Sentinel-2 was conducted in summer 2020, and for the first time, a high-precision dataset of China's oases (abbreviation HDCO) with a resolution of 1 meter was constructed. HDCO comprises 1,466 oases with a total area of 277,375.56 km2. The kappa coefficient for this dataset validated by the field survey was 0.8686 and the AUC value for the ROC curve was 0.935. In addition, information on the geographic coordinates, climatic conditions, major landforms, and hydrological features of each oasis was added to the attribute table of the dataset. This dataset enables researchers to quantitatively monitor location and area of oases, fosters exploration of the relationship between oases and human under climate change and urbanization.

3.
ACS Omega ; 9(26): 28293-28310, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38973882

RESUMO

The addition of ammonia and hydrogen into natural gas fuel is an effective method to reduce carbon emissions. This study aims to investigate the effect of adding ammonia and hydrogen on the mechanism of natural gas combustion and emission characteristics. Based on a self-developed mixed gas deflagrate experimental platform, the deflagrate characteristics, emission characteristics, and chemical reaction kinetics mechanism of mixed gas fuels under different composition ratios (natural gas 0-100%, hydrogen 10-85%, and ammonia 0-100%) were studied. The results indicate that the propagation of the deflagration shock wave can be categorized into an initial stage (L < 3 m) and a development stage (L > 3 m) based on the observed trend of shock wave intensity variation with distance. The intensity of the deflagration shock wave for the mixed gases increases monotonically as the hydrogen content ratio rises. In contrast, the impact of the ammonia content ratio on the shock wave intensity exhibits a distinct pattern that varies with changes in the equivalence ratio and hydrogen content ratio. In terms of carbon emissions per unit of heat value produced by the fuel, adding hydrogen to natural gas proves to be more effective at reducing carbon emissions than adding ammonia. When the ammonia content ratio is 50% and the hydrogen content ratio is 40%, the combustion performance of the mixed gas fuel is similar to that of natural gas, but its carbon emissions are lower than 30% of natural gas, making it a new type of mixed fuel with potential application value; the interaction between reflected pressure waves and flames is the main reason for the fluctuation of deflagrate shock wave pressure; ammonia lowers the temperature of the reaction system by reducing the concentration of OH radicals.

4.
Anal Chem ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980807

RESUMO

Stroke is an acute injury of the central nervous system caused by the disorders of cerebral blood circulation, which has become one of the major causes of disability and death. Hemorrhage, particularly subarachnoid hemorrhage (SAH), is one of the poorest prognostic factors in stroke, which is related to the thrombolytic therapy, and has been considered very dangerous. In this context, the MR angiography with high sensitivity and resolution has been developed based on biocompatible paramagnetic ultrasmall NaGdF4 nanoprobes. Owing to the appropriate hydrodynamic diameter, the nanoprobe can be confined inside the blood vessels and it only extravasates at the vascular injury site when the bleeding occurs. Relying on this property, the three-dimensional (3D) anatomic structures of artery occlusion of stroke rat can be precisely visualized; reperfusion-related SAH has been successfully visualized and identified. Benefiting from the long blood half-life of the nanoprobe, the observation window of MR angiography can last for the whole period of reperfusion, thereby monitoring the probable SAH in real time during thrombolytic therapy. More importantly, through reconstruction of multiparametric MRI, the arterial occlusion, cerebral ischemic region, and SAH can be simultaneously visualized in vivo in a 3D manner for the first time. Therefore, the current study provides a novel approach for both noninvasive 3D vascular visualization and hemorrhage alert, which possesses great prospects for clinical translation.

5.
Biomaterials ; 311: 122659, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38861831

RESUMO

Pathogenic infection leads to excessive senescent cell accumulation and stagnation of wound healing. To address these issues, we devise and develop a hydrogen selenide (H2Se)-evolving bio-heterojunction (bio-HJ) composed of graphene oxide (GO) and FeSe2 to deracinate bacterial infection, suppress cellular senescence and remedy recalcitrant infected wounds. Excited by near-infrared (NIR) laser, the bio-HJ exerts desired photothermal and photodynamic effects, resulting in rapid disinfection. The crafted bio-HJ could also evolve gaseous H2Se to inhibit cellular senescence and dampen inflammation. Mechanism studies reveal the anti-senescence effects of H2Se-evolving bio-HJ are mediated by selenium pathway and glutathione peroxidase 1 (GPX1). More critically, in vivo experiments authenticate that the H2Se-evolving bio-HJ could inhibit cellular senescence and potentiate wound regeneration in rats. As envisioned, our work not only furnishes the novel gasotransmitter-delivering bio-HJ for chronic infected wounds, but also gets insight into the development of anti-senescence biomaterials.

6.
Fitoterapia ; 177: 106052, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38848978

RESUMO

Hypoxia-inducing factor-1α (HIF-1α) is overexpressed in variety of tumor patients and plays an important role in the regulation of hypoxia response in tumor cells. Therefore, its inhibitors have become one of the targets for the treatment of a variety of cancers. Two series of panaxadiol (PD) ester derivatives containing pyrazole (18a-j) and pyrrole (19a-n) moiety were synthesized and their HIF-1α inhibitory activities were evaluated. Among all the target compouds, compounds 18c, 19d, and 19n (IC50 = 8.70-10.44 µM) showed better HIF-1α inhibitory activity than PD (IC50 = 13.35 µM). None of these compounds showed cytotoxicity above 100 µM and inhibited HIF-1α transcription in a dose-dependent manner. These compounds showed good antitumor activity and provide lead compounds for further design and activity study of PD ester derivatives.

7.
ACS Omega ; 9(22): 23853-23863, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38854566

RESUMO

To evaluate the explosion hazard of CH4/H2 mixtures, experiments were conducted in a long and closed pipeline with a length-to-diameter ratio of 51 and built-in obstacles, and the characteristic parameters of deflagration shock waves were analyzed under different hydrogen blending ratios (0 ≤ λ ≤ 100%) and equivalence ratios (0.5 ≤ Φ ≤ 3). The results indicate that within the range of Φ = 0.8-1.2, the explosion overpressure (P P) exhibits a "two-zone" structure distribution. When 0 ≤ λ ≤ 80%, P P shows an initial increase and then a decrease in both regions, while deflagration to detonation transition (DDT) occurs in the second evolution region when λ = 100%, which is caused by the different strengths of the positive feedback mechanism coupled with flames and shock waves. The P max, (dP/dt)max, and V a show a trend of first increasing and then decreasing and monotonically increasing with the increase of the equivalence ratio and hydrogen blending ratio, respectively, and reach their maximum values at Φ = 1.0 and λ = 100%. For CH4/H2 mixtures with low hydrogen blending ratios (λ = 0 and 20%), the P max and (dP/dt)max in the fuel-lean conditions (Φ = 0.9 and 0.8) are higher than those in the fuel-rich conditions (Φ = 1.1 and 1.2), while the CH4/H2 mixtures under high hydrogen blending ratios (λ = 80 and 100%) are the opposite. Overall, the increase in H2 at a high hydrogen blending ratio and the increase in the equivalence ratio at a fuel-lean condition significantly enhance the average V a. In addition, chemical kinetics analysis found that R38 and R52 elementary reactions are the dominant elementary reactions that promote and inhibit temperature increase, respectively. Their temperature sensitivity coefficients are negatively correlated with the hydrogen blending ratio and positively correlated with the equivalence ratio. The research results provide vital information for evaluating the explosion hazards of CH4/H2 mixtures and developing safety protection measures.

8.
J Cardiothorac Surg ; 19(1): 379, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926836

RESUMO

BACKGROUND: For acute type A aortic dissection involving the aortic root with root diameter no more than 45 mm, there are various aortic root repair techniques. In this study, a novel surgical technique using a pericardial autograft for aortic root repair was introduced. We described its surgical steps in detail and compare its clinical outcomes with direct suture technique. METHODS: Between July 2017 and August 2022, 95 patients with acute type A aortic dissection who underwent aortic root repair were enrolled, including aortic root repair using pericardial autograft (group A, n = 49) or direct suture (group B, n = 46). The patient's clinical data were retrospectively analyzed, and a 5-year follow-up was conducted. RESULTS: The 30-day mortality, re-exploration for bleeding, postoperative new-onset renal failure requiring continuous renal replacement therapy, stroke, and paraplegia occurred in 3%, 4%, 11%, 5%, and 2% of the overall patients, respectively. There was no significant difference in the 30-day mortality and complication rate between the two groups. The 30-day mortality and re-exploration for bleeding marked the primary endpoint events. Logistic regression analysis indicated that there was a significant correlation between the primary endpoint events and surgical technique (odds ratio, 0.002; 95% confidence interval, 0-0.159; P = 0.026). The aortic valve insufficiency of the two groups were significantly improved after operation (group A, P < 0.001; group B, P < 0.001). During follow-up, there was no significant difference in short-term survival between the two groups after surgery (log-rank P = 0.75), and all patients were free from reoperation for aortic disease. CONCLUSIONS: Patients who underwent aortic root repair using pericardial autograft tended to have reduced 30-day mortality and a lower risk of re-exploration for bleeding. Using pericardial autograft for aortic root repair is a safe and useful approach for patients with acute type A aortic dissection involving the aortic root.


Assuntos
Dissecção Aórtica , Pericárdio , Humanos , Dissecção Aórtica/cirurgia , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Pericárdio/transplante , Resultado do Tratamento , Autoenxertos , Aneurisma da Aorta Torácica/cirurgia , Idoso , Doença Aguda , Complicações Pós-Operatórias , Implante de Prótese Vascular/métodos , Transplante Autólogo , Seguimentos
9.
Poult Sci ; 103(9): 103929, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38943802

RESUMO

This study aimed to investigate the developmental change of body growth and gene expression related to fatty acid uptake and oxidation in the yolk sac membrane (YSM) and jejunum during embryogenesis in Muscovy ducks. The weights of embryos and yolk sac (YS) (5 embryos per replicate, n = 6) were recorded on embryonic days (E)16, E19, E22, E25, E28, E31, and the day of hatch (DOH). The fat and fatty acid contents in YSM, jejunal histology, and gene expression related to fatty acid metabolism in YSM and jejunum were determined in each sampling time. Among the nonlinear models, the maximum growth is estimated at 2.83 (E22.5), 2.67 (E22.1), and 2.60 (E21.3) g/d using logistic, Gompertz, and Von Bertalanffy models, respectively. The weight of YS, and ether extract-free YS as well as the amounts of fat and fatty acids in YS decreased (P < 0.05) linearly, whereas the villus height, crypt depth, villus height/crypt depth, and musculature thickness in jejunum increased (P < 0.05) linearly during embryogenesis. The mRNA expression of CD36, SLC27A4, and FABP1 related to fatty acid uptake as well as the mRNA and protein expressions of PPARα and CPT1 related to fatty acid oxidation increased in a quadratic manner (P < 0.05) in both YS and jejunum, and the maximum values were achieved during E25 to E28. In conclusion, the maximum growth rate of Muscovy duck embryos was estimated at 2.60 to 2.83 g/d on E21.3 to E23.5, while the accumulations of lipid and fatty acid in YS were decreased in association with the increased absorptive area of morphological structures in jejunum. The gene and protein expression involved in fatty acid metabolism displayed a similar enhancement pattern between YSM and jejunum during E25 to E28, suggesting that fatty acid utilization could be strengthened to meet the energy demand for embryonic development.

10.
PLoS One ; 19(6): e0304946, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38875289

RESUMO

Agarwood is a resinous heartwood of Aquilaria sinensis that is formed in response to mechanical wounding. In the present study pre-treatment of Aquilaria sinensis was carried out, and then the dominant fungi were isolated and purified from the surface and electroshock holes of trees. The isolated Trichoderma sp. and Neurospora sp. were then screened for resistance against benzyl acetone and then inoculated into healthy Aquilaria sinensis trees. After six months, the agarwood was collected for analysis. The chemical composition of incense was analyzed using gas chromatography-mass spectroscopy, and 82 chemical constituents were identified. Agarwood products formed by using Trichoderma sp. and Neurospora sp. consisted of 50.22% and 48.71% ether extracts, respectively, which surpassed the 10% threshold specified by the Chinese Pharmacopoeia. Similarly, relative aromatic contents in the two agarwood products were 30.1% and 32.86%, while proportions of sesquiterpene constituents were 10.21% and 11.19%, respectively. These two agarwood-specific chemical constituents accounted for a large proportion of the total chemical composition, which showed that the generated agarwood was of good quality. The results of the study revealed that both Trichoderma sp. and Neurospora sp. were able to effectively induce agarwood production in Aquilaria sinensis trees in 6 months. This study expands the library of fungi that promote the production of agarwood from Aquilaria sinensis trees.


Assuntos
Thymelaeaceae , Trichoderma , Madeira , Thymelaeaceae/microbiologia , Thymelaeaceae/química , Trichoderma/metabolismo , Trichoderma/isolamento & purificação , Madeira/microbiologia , Madeira/química , Cromatografia Gasosa-Espectrometria de Massas , Árvores/microbiologia
11.
Mult Scler Relat Disord ; 87: 105647, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38838422

RESUMO

BACKGROUND: Observational studies looking at clinical a++nd MRI outcomes of treatments in pediatric MS, could assess current treatment algorithms, and provide insights for designing future clinical trials. OBJECTIVE: To describe baseline characteristics and clinical and MRI outcomes in MS patients initiating ocrelizumab and fingolimod under 18 years of age. METHODS: MS patients seen at 12 centers of US Network of Pediatric MS were included in this study if they had clinical and MRI follow-up and started treatment with either ocrelizumab or fingolimod prior to the age of 18. RESULTS: Eighty-seven patients initiating fingolimod and 52 initiating ocrelizumab met the inclusion criteria. Before starting fingolimod, mean annualized relapse rate was 0.43 (95 % CI: 0.29 - 0.65) and 78 % developed new T2 lesions while during treatment it was 0.12 (95 % CI: 0.08 - 1.9) and 47 % developed new T2 lesions. In the ocrelizumab group, the mean annualized relapse rate prior to initiation of treatment was 0.64 (95 % CI: 0.38-1.09) and a total of 83 % of patients developed new T2 lesions while during treatment it was 0.09 (95 % CI: 0.04-0.21) and none developed new T2 lesions. CONCLUSION: This study highlights the importance of evaluating current treatment methods and provides insights about the agents in the ongoing phase III trial comparing fingolimod and ocrelizumab.


Assuntos
Anticorpos Monoclonais Humanizados , Cloridrato de Fingolimode , Imageamento por Ressonância Magnética , Humanos , Cloridrato de Fingolimode/efeitos adversos , Cloridrato de Fingolimode/uso terapêutico , Cloridrato de Fingolimode/administração & dosagem , Feminino , Masculino , Adolescente , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/administração & dosagem , Criança , Fatores Imunológicos/efeitos adversos , Fatores Imunológicos/administração & dosagem , Imunossupressores/efeitos adversos , Imunossupressores/administração & dosagem , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/diagnóstico por imagem , Resultado do Tratamento , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Encéfalo/patologia
12.
Front Plant Sci ; 15: 1354384, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38742214

RESUMO

One-time application of blended controlled-release nitrogen fertilizer (CRN) has the potential to solve the difficulty of top-dressing fertilizer in the cultivation of rice and reduce the cost of CRN fertilizer application. However, its effects on rice dry matter and nitrogen (N) accumulation and translocation, yield and N-use efficiency (NUE) remain uncertain. Field experiments were carried out at three sites (Mingguang, Chaohu, and Guichi) in the Yangtze River Delta in China to compare the effects of the conventional split applications of urea and the blended CRN and on post-anthesis dry matter and N accumulation and translocation, yield, and NUE in rice at 0, 60, 120, 180, and 240 kg N ha-1. The results showed that at the equal N application rates, compared under the conventional N fertilizer treatment, the blended CRN application significantly increased the rice yield by an average of 0.9-6.9%, mainly due to increase the number of spikelets per panicle. The highest yield achieved with blended CRN treatment occurred at 200 kg N ha-1, with an NUE of 45.9%. Moreover, in comparison to the conventional N fertilizer, the blended CRN treatment increased pre-anthesis N translocation (Pre-NT) by 1.0-19.8%, and the contribution of pre-NT to grain N by 0.2-8.7%, and NUE by 3.2-28.4%. Meanwhile, the blended CRN treatment reduced labor costs by 1800 Yuan ha-1 and enhanced the economic gains by 21.5-68.8%. Therefore, one-time application of blended CRN ≤ 200 kg N ha-1 application rate improved rice yield, NUE, and economic profit compared to equivalent rates of split applied conventional N fertilizers.

14.
Environ Technol ; : 1-17, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38820568

RESUMO

This study aimed to create a comprehensive evaluation method for sewage sludge (SS) treatment and disposal technologies, considering carbon emission and environmental impacts. Life cycle assessment (LCA) were conducted on six SS treatment and disposal technologies in China. The assessments used the IPCC emission factor approach to calculate carbon emissions and the CML2001 method to determine environmental impact factors. Additionally, a colour-coded method was implemented to quantify the evaluation results. The study found that S1 (anaerobic digestion + land application) had the lowest carbon emissions and environmental impact, making it the optimal technology. The S1 scenario had carbon emissions of 669 kg CO2(t DS)-1 and environmental impacts of 5.20E-10. A sensitivity analysis was conducted to show the impacts of each unit in the six technologies on total carbon emissions and environmental impacts. The results showed that landfilling has a high sensitivity to carbon emissions and environmental impacts. Therefore, controlling greenhouse gases and toxic substances in sludge landfills is crucial for reducing carbon emissions and environmental pollution.

15.
Viruses ; 16(5)2024 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-38793564

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) is a pathogen that causes severe abortions in sows and high piglet mortality, resulting in huge economic losses to the pig industry worldwide. The emerging and novel PRRSV isolates are clinically and biologically important, as there are likely recombination and pathogenic differences among PRRSV genomes. Furthermore, the NADC34-like strain has become a major epidemic strain in some parts of China, but the characterization and pathogenicity of the latest strain in Inner Mongolia have not been reported in detail. In this study, an NADC34-like strain (CHNMGKL1-2304) from Tongliao City, Inner Mongolia was successfully isolated and characterized, and confirmed the pathogenicity in pigs. The phylogenetic tree showed that this strain belonged to sublineage 1.5 and had high homology with the strain JS2021NADC34. There is no recombination between CHNMGKL1-2304 and any other domestic strains. Animal experiments show that the CHNMGKL1-2304 strain is moderately virulent to piglets, which show persistent fever, weight loss and high morbidity but no mortality. The presence of PRRSV nucleic acids was detected in both blood, tissues, nasal and fecal swabs. In addition, obvious pathological changes and positive signals were observed in lung, lymph node, liver and spleen tissues when subjected to hematoxylin-eosin (HE) staining and immunohistochemistry (IHC). This report can provide a basis for epidemiological investigations and subsequent studies of PRRSV.


Assuntos
Genoma Viral , Filogenia , Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Animais , Suínos , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/patogenicidade , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , China , Síndrome Respiratória e Reprodutiva Suína/virologia , Síndrome Respiratória e Reprodutiva Suína/patologia , Virulência , Evolução Molecular
16.
Arch Pharm (Weinheim) ; : e2400131, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38678538

RESUMO

Three series of N-{[4-([1,2,4]triazolo[1,5-α]pyridin-6-yl)-5-(6-methylpyridin-2-yl)-1H-imidazol-2-yl]methyl}acetamides (14a-d, 15a-n, and 16a-f) were synthesized and evaluated for activin receptor-like kinase 5 (ALK5) inhibitory activities in an enzymatic assay. The target compounds showed high ALK5 inhibitory activity and selectivity. The half maximal inhibitory concentration (IC50) for phosphorylation of ALK5 of 16f (9.1 nM), the most potent compound, was 2.7 times that of the clinical candidate EW-7197 (vactosertib) and 14 times that of the clinical candidate LY-2157299. The selectivity index of 16f against p38α mitogen-activated protein kinase was >109, which was much higher than that of positive controls (EW-7197: >41, and LY-2157299: 4). Furthermore, a molecular docking study provided the interaction modes between the target compounds and ALK5. Compounds 14c, 14d, and 16f effectively inhibited the protein expression of α-smooth muscle actin (α-SMA), collagen I, and tissue inhibitor of metalloproteinase 1 (TIMP-1)/matrix metalloproteinase 13 (MMP-13) in transforming growth factor-ß-induced human umbilical vein endothelial cells. Compounds 14c and 16f showed especially high activity at low concentrations, which suggests that these compounds could inhibit myocardial cell fibrosis. Compounds 14c, 14d, and 16f are potential preclinical candidates for the treatment of cardiac fibrosis.

17.
J Am Chem Soc ; 146(15): 10640-10654, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38568727

RESUMO

Foreign ions as additives are of great significance for realizing excellent control over the morphology of noble metal nanostructures in the state-of-the-art seed-mediated growth method; however, they remain largely unexplored in chiral synthesis. Here, we report on a Cu2+-dominated chiral growth strategy that can direct the growth of concave chiral Au nanoparticles with C3-dominant chiral centers. The introduction of trace amounts of Cu2+ ions in the seed-mediated chiral growth process is found to dominate the chirality transfer from chiral molecules to chiral nanoparticles, leading to the formation of chiral nanoparticles with a concave VC geometry. Both experimental and theoretical results further demonstrate the correlation between the nanoparticle structure and optical chirality for the concave chiral nanoparticle. The Cu2+ ion is found to dominate the chiral growth by selectively activating the deposition of Au atoms along the [110] and [111] directions, facilitating the formation of the concave VC. We further demonstrate that the Cu2+-dominated chiral growth strategy can be employed to generate a variety of concave chiral nanoparticles with enriched geometric chirality and desired chiroptical properties. Concave chiral nanoparticles also exhibit appealing catalytic activity and selectivity toward electrocatalytic oxidation of enantiomers in comparison to helicoidal nanoparticles. The ability to tune the geometric chirality in a controlled manner by simply manipulating the Cu2+ ions as additives opens up a promising strategy for creating chiral nanomaterials with increasing architectural diversity for chirality-dependent optical and catalytic applications.

18.
Zhongguo Zhong Yao Za Zhi ; 49(3): 770-778, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621881

RESUMO

This paper aims to study the therapeutic effect of Massa Medicata Fermentata on hyperlipidemia model rats and investigate its mechanism of hypolipidemic effect with the help of non-targeted metabolomics. The mixed hyperlipidemia model rats were constructed by giving high-fat chow. After successful modeling, the rats were divided into the model group, pravastatin sodium group(4.4 mg·kg~(-1)), lipotropic group(0.1 g·kg~(-1)), high-dose group(2.4 g·kg~(-1)), medium-dose group(1.2 g·kg~(-1)), and low-dose group(0.6 g·kg~(-1)) of Massa Medicata Fermentata, and they were administered for four weeks once daily. An equal volume of ultrapure water was given to the blank group and model group. Serum lipid level and liver hematoxylin-eosin(HE) staining were used as indicators to estimate the intervention effect of Massa Medicata Fermentata on mixed hyperlipidemia, and the changes in metabolites in plasma of mixed hyperlipidemia model rats were analyzed by non-targeted metabolomics. The mechanism of the hypolipidemic effect of Massa Medicata Fermentata was analyzed through metabolite pathway enrichment. The results showed that compared with the model group, the Massa Medicata Fermentata administration group, especially the high-dose group, could significantly reduce the content of total cholesterol(TC), triglyceride(TG), and low-density lipoprotein cholesterol(LDL-c)(P<0.05 or P<0.01), and liver HE staining revealed that the number of adipocytes in the high-dose group was reduced to some extent. The potential biomarkers obtained by non-targeted metabolomics screening included glycerol 3-phosphate, sphingomyelin, sphingosine 1-phosphate, and deoxyuridine, which were mainly involved in the sphingolipid metabolism process, glycerophospholipid metabolism process, glycerol ester metabolism pathway, and pyrimidine metabolism pathway, totaling four possible metabolic pathways related to lipid metabolism. This study provides a reference for an in-depth investigation of the hypolipidemic mechanism of Massa Medicata Fermentata, which is of great significance for further promoting the clinical application of Massa Medicata Fermentata and increasing the indications.


Assuntos
Medicamentos de Ervas Chinesas , Hiperlipidemias , Ratos , Animais , Medicamentos de Ervas Chinesas/farmacologia , Fígado , Hiperlipidemias/tratamento farmacológico , Metabolômica , Colesterol , Dieta Hiperlipídica/efeitos adversos
19.
Plant Commun ; 5(6): 100856, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38431772

RESUMO

Actinidia arguta, the most widely distributed Actinidia species and the second cultivated species in the genus, can be distinguished from the currently cultivated Actinidia chinensis on the basis of its small and smooth fruit, rapid softening, and excellent cold tolerance. Adaptive evolution of tetraploid Actinidia species and the genetic basis of their important agronomic traits are still unclear. Here, we generated a chromosome-scale genome assembly of an autotetraploid male A. arguta accession. The genome assembly was 2.77 Gb in length with a contig N50 of 9.97 Mb and was anchored onto 116 pseudo-chromosomes. Resequencing and clustering of 101 geographically representative accessions showed that they could be divided into two geographic groups, Southern and Northern, which first diverged 12.9 million years ago. A. arguta underwent two prominent expansions and one demographic bottleneck from the mid-Pleistocene climate transition to the late Pleistocene. Population genomics studies using paleoclimate data enabled us to discern the evolution of the species' adaptation to different historical environments. Three genes (AaCEL1, AaPME1, and AaDOF1) related to flesh softening were identified by multi-omics analysis, and their ability to accelerate flesh softening was verified through transient expression assays. A set of genes that characteristically regulate sexual dimorphism located on the sex chromosome (Chr3) or autosomal chromosomes showed biased expression during stamen or carpel development. This chromosome-level assembly of the autotetraploid A. arguta genome and the genes related to important agronomic traits will facilitate future functional genomics research and improvement of A. arguta.


Assuntos
Actinidia , Genoma de Planta , Tetraploidia , Actinidia/genética , Evolução Molecular , Adaptação Fisiológica/genética , Evolução Biológica
20.
Neural Netw ; 174: 106265, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38552351

RESUMO

Graph Transformers (GTs) have achieved impressive results on various graph-related tasks. However, the huge computational cost of GTs hinders their deployment and application, especially in resource-constrained environments. Therefore, in this paper, we explore the feasibility of sparsifying GTs, a significant yet under-explored topic. We first discuss the redundancy of GTs based on the characteristics of existing GT models, and then propose a comprehensive Graph Transformer SParsification (GTSP) framework that helps to reduce the computational complexity of GTs from four dimensions: the input graph data, attention heads, model layers, and model weights. Specifically, GTSP designs differentiable masks for each individual compressible component, enabling effective end-to-end pruning. We examine our GTSP through extensive experiments on prominent GTs, including GraphTrans, Graphormer, and GraphGPS. The experimental results demonstrate that GTSP effectively reduces computational costs, with only marginal decreases in accuracy or, in some instances, even improvements. For example, GTSP results in a 30% reduction in Floating Point Operations while contributing to a 1.8% increase in Area Under the Curve accuracy on the OGBG-HIV dataset. Furthermore, we provide several insights on the characteristics of attention heads and the behavior of attention mechanisms, all of which have immense potential to inspire future research endeavors in this domain. Our code is available at https://github.com/LiuChuang0059/GTSP.

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