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1.
Eur J Pharm Biopharm ; : 114435, 2024 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-39103002

RESUMO

The clinical usage of docetaxel (DTX) is severely hindered by the dose-limiting neutropenia and peripheral neurotoxicity of polysorbate 80-solubilized DTX injection, and there are no alternative formulations until now. In this study, we developed a new liposomal formulation of DTX to reduce its toxicities, accompanying with the greatly improved antitumor activity. The DTX was encapsulated into liposomes in the form of hydrophilic glutathione (GSH)-conjugated prodrugs using a click drug loading method, which achieved a high encapsulation efficiency (∼95 %) and loading capacity (∼30 % wt). The resulting liposomal DTX-GSH provided a sustained and efficient DTX release (∼50 % within 48 h) in plasma, resulting in a greatly improved antitumor activities as compared with that of polysorbate 80-solubilized DTX injection in the subcutaneous and orthotopic 4 T1 breast tumor bearing mice. Even large tumors > 500 mm3 could be effectively inhibited and shrunk after the administration of liposomal DTX-GSH. More importantly, the liposomal DTX-GSH significantly decreased the neutropenia and peripheral neurotoxicity as compared with that of polysorbate 80-solubilized DTX injection at the equivalent dose. These data suggested that the liposomal DTX-GSH might become a superior alternative formulation to the commercial DTX injection.

2.
Environ Sci Technol ; 58(31): 13636-13647, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-38961559

RESUMO

Emerging data suggest a close correlation between ambient fine particle (AFP) exposure and eye disorders and pinpoint potential threats of AFPs to eye health in humans. However, the possible passage (including direct intrusion) and the interactions of AFPs with the eye microenvironment in addition to morphological and physiological injuries remain elusive. To this end, the likely transport of AFPs into the eyes via blood-ocular barrier (BOB) in humans and animals was investigated herein. Exogenous particles were recognized inside human eyes with detailed structural and chemical fingerprints. Importantly, comparable AFPs were found in sera with constant structural and chemical fingerprints, hinting at the translocation pathway from blood circulation into the eye. Furthermore, we found that the particle concentrations in human eyes from patients with diabetic retinopathy were much higher than those from patients with no fundus pathological changes (i.e., myopia), indicating that the damaged BOB increased the possibility of particle entrance. Our diseased animal model further corroborated these findings. Collectively, our results offer a new piece of evidence on the intrusion of exogenous particles into human eyes and provide an explanation for AFP-induced eye disorders, with substantially increased risk in susceptible individuals with BOB injuries.


Assuntos
Material Particulado , Humanos , Animais , Olho/patologia , Masculino
3.
BMC Psychiatry ; 24(1): 517, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039478

RESUMO

BACKGROUND: Depression and anxiety symptoms among medical students are often a concern. The Patient Health Questionnaire-Four (PHQ-4), an important tool for depression and anxiety screening, is commonly used and easy to administer. This study aimed to assess and update the longitudinal measurement invariance and psychometric properties of the simplified Chinese version. METHODS: A three-wave longitudinal survey was conducted among healthcare students using the PHQ-4. Structural validity was based on one-factor, two-factor, and second-order factor models, construct validity was based on the Self-Rated Health Questionnaire (SRHQ), Sleep Quality Questionnaire (SQQ), and Rosenberg Self-Esteem Scale (RSES), and longitudinal measurement invariance (LMI), internal consistency, and test-retest reliability were based on structural consistency across three time points. RESULTS: The results of the confirmatory factor analysis indicated that two-factor model was the best fit, and LMI was supported at three time points. Inter-factor, factor-total, and construct validity correlations of the PHQ-4 were acceptable. Additionally, Cronbach's alpha, McDonald's omega, and the intraclass correlation coefficient demonstrated acceptable/moderate to excellent reliability of the PHQ-4. CONCLUSIONS: This study adds new longitudinal evidence that the Chinese version of the PHQ-4 has promising LMI and psychometric properties. Such data lends confidence to the routine and the expanded use of the PHQ-4 for routine screening of depression and anxiety in Chinese healthcare students.


Assuntos
Ansiedade , Depressão , Questionário de Saúde do Paciente , Psicometria , Humanos , China , Feminino , Masculino , Estudos Longitudinais , Reprodutibilidade dos Testes , Depressão/psicologia , Depressão/diagnóstico , Ansiedade/psicologia , Ansiedade/diagnóstico , Adulto , Adulto Jovem , Estudantes de Medicina/psicologia , Análise Fatorial , Inquéritos e Questionários/normas
4.
Front Pharmacol ; 15: 1356725, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39070786

RESUMO

Objective: Both camrelizumab plus paclitaxel and carboplatin (CTC) and sintilimab plus gemcitabine and cisplatin or carboplatin (SGP) have been approved by the National Medical Products Administration of China (NMPA) for the first-line treatment of local advanced or metastatic sqNSCLC. However, the comparison of the two treatments as first-line treatments in efficacy or pharmacoeconomics has barely been studied. To deeply understand the costs and outcomes of the two treatments, this work directly compared the cost-effectiveness for the first-line treatment of local advanced or metastatic squamous NSCLC in the Chinese mainland. Methods: A network meta-analysis was first performed based on the three clinical trials, namely, CameL-Sq, ORIENT-12, and C-TONG1002, to compare the clinical benefits of the two treatments. The Weibull approximation was applied to further calculate the life expectancy of the two treatments. The partitioned survival model (PSM) was next established, and one-way sensitivity analysis and probabilistic sensitivity analysis were also performed to evaluate the stability of the underlying parameter values and assumptions within the model. Results: CTC treatment gained 0.68 QALYs and cost $14,764. SGP treatment gained 0.54 QALYs and cost $14,584. The CTC arm gained 0.14 additional QALYs and cost $179 more than the SGP arm, and the ICERs was $1,269/QALY, which was lower than one-fold GDP per capita in the Chinese mainland ($12,734 GDP per capita in 2022). In probabilistic sensitivity analysis, when the WTP ranged from $12,734-38,202 (1-3 folds, 2022 GDP per capita in China), the CTC group had higher probabilities than the SGP group for being cost effective, which ranged from 85.65% to 88.38%. Conclusion: From the perspective of the payers, camrelizumab plus chemotherapy was cost-effective compared with sintilimab plus chemotherapy for the first-line treatment of local advanced or metastatic squamous NSCLC in the Chinese mainland.

5.
Adv Sci (Weinh) ; : e2401014, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39083299

RESUMO

Precise identification of glioblastoma (GBM) microinfiltration, which is essential for achieving complete resection, remains an enormous challenge in clinical practice. Here, the study demonstrates that Raman spectroscopy effectively identifies GBM microinfiltration with cellular resolution in clinical specimens. The spectral differences between infiltrative lesions and normal brain tissues are attributed to phospholipids, nucleic acids, amino acids, and unsaturated fatty acids. These biochemical metabolites identified by Raman spectroscopy are further confirmed by spatial metabolomics. Based on differential spectra, Raman imaging resolves important morphological information relevant to GBM lesions in a label-free manner. The area under the receiver operating characteristic curve (AUC) for Raman spectroscopy combined with machine learning in detecting infiltrative lesions exceeds 95%. Most importantly, the cancer cell threshold identified by Raman spectroscopy is as low as 3 human GBM cells per 0.01 mm2. Raman spectroscopy enables the detection of previously undetectable diffusely infiltrative cancer cells, which holds potential value in guiding complete tumor resection in GBM patients.

6.
Front Plant Sci ; 15: 1401525, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38966140

RESUMO

Powdery mildew caused by Blumeria graminis f. sp. tritici (Bgt) seriously threatens wheat production worldwide. It is imperative to identify novel resistance genes from wheat and its wild relatives to control this disease by host resistance. Dasypyrum villosum (2n = 2x = 14, VV) is a relative of wheat and harbors novel genes for resistance against multi-fungal diseases. In the present study, we developed a complete set of new wheat-D. villosum disomic introgression lines through genomic in situ hybridization (GISH), fluorescence in situ hybridization (FISH) and molecular markers analysis, including four disomic substitution lines (2n=42) containing respectively chromosomes 1V#6, 2V#6, 3V#6, and 6V#6, and four disomic addition lines (2n=44) containing respectively chromosomes 4V#6, 5V#6, 6V#6 and 7V#6. These lines were subsequently evaluated for their responses to a mixture Bgt isolates at both seedling and adult-plant stages. Results showed that introgression lines containing chromosomes 3V#6, 5V#6, and 6V#6 exhibited resistance at both seedling and adult-plant stages, whereas the chromosome 4V#6 disomic addition line NAU4V#6-1 exhibited a high level of adult plant resistance to powdery mildew. Moreover, two translocation lines were further developed from the progenies of NAU4V#6-1 and the Ph1b mutation line NAU0686-ph1b. They were T4DL·4V#6S whole-arm translocation line NAU4V#6-2 and T7DL·7DS-4V#6L small-fragment translocation line NAU4V#6-3. Powdery mildew tests of the two lines confirmed the presence of an adult-plant powdery mildew resistance gene, Pm4VL, located on the terminal segment of chromosome arm 4V#6L (FL 0.6-1.00). In comparison with the recurrent parent NAU0686 plants, the T7DL·7DS-4V#6L translocation line NAU4V#6-3 showed no obvious negative effect on yield-related traits, providing a new germplasm in breeding for resistance.

7.
PLoS One ; 19(7): e0306867, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38980890

RESUMO

With the development of earthquake disaster reduction efforts in China, the content of earthquake disaster reduction policies has become increasingly enriched and improved. Particularly, multiple provincial governments have proposed earthquake disaster reduction planning policies. It is important to explore whether these policies can affect disaster mitigation. Therefore, this paper summarizes the earthquake disaster reduction plans and factors influencing seismic resilience. Panel data from 24 provinces between 2012 and 2021 were collected, and a difference-in-differences approach was used to construct an econometric model to evaluate the policy effects and analyze the enhancement of seismic resilience. The results show that the implementation of earthquake disaster reduction policies has a positive impact on earthquake monitoring, evacuation, and emergency relief capabilities, and the estimated policy effects are statistically significant. Moreover, a series of tests were conducted. The conclusions are as follows: (1) Earthquake disaster reduction policies have a positive impact on the improvement of seismic resilience in provinces. (2) Provinces with a higher number of earthquakes experience more significant effects from earthquake disaster reduction policies. (3) Provinces with higher seismic peak ground acceleration values exhibit more pronounced improvements in seismic resilience.


Assuntos
Planejamento em Desastres , Terremotos , China , Humanos , Planejamento em Desastres/métodos , Desastres
8.
Plants (Basel) ; 13(13)2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38999715

RESUMO

Stripe rust (Puccinia striiformis West. f.sp. tritici, Pst) is a destructive disease that seriously threatens wheat production globally. Exploring novel resistance genes for use in wheat breeding is an urgent need, as continuous Pst evolution frequently leads to a breakdown of host resistance. Here, we identified a set of wheat-Dasypyrum villosum 01I139 (V#6) disomic introgression lines for the purpose of determining their responses to a mixture of Pst isolates CYR32, CYR33 and CYR34 at both seedling and adult-plant stages. The results showed that all introgression lines exhibited high susceptibility at the seedling stage, with infection-type (IT) scores in the range of 6-8, whereas, for chromosomes 5V#6 and 7V#6, disomic addition lines NAU5V#6-1 and NAU7V#6-1 displayed high resistance at the adult-plant stage, indicating that adult-plant resistance (APR) genes were located on them. Further, in order to transfer the stripe-rust resistance on chromosome 7V#6, four new wheat-D. villosum introgression lines were identified, by the use of molecular cytogenetic approaches, from the self-pollinated seeds of 7D and 7V#6, in double monosomic line NAU7V#6-2. Among them, NAU7V#6-3 and NAU7V#6-4 were t7V#6L and t7V#6S monosomic addition lines, and NAU7V#6-5 and NAU7V#6-6 were homozygous T7DS·7V#6L and T7DL·7V#6S whole-arm translocation lines. Stripe-rust tests and genetic analyses of chromosome 7V#6 introgression lines revealed a dominant APR gene designated as Yr7VS on the chromosome arm 7V#6S. Comparison with the homozygous T7DL·7V#6S translocation line and the recurrent parent NAU0686 showed no significant differences in yield-related traits. Thus, T7DL·7V#6S whole-arm translocation with the APR gene Yr7VS provided a valuable germplasm for breeding for resistance.

9.
Anal Methods ; 16(30): 5231-5238, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39007341

RESUMO

Deoxynivalenol (DON) has drawn considerable attention for its obvious pathogenicity and wide use in agro-products, which cause a potential threat to human health. In this work, an electrochemical immunosensor is developed for the highly sensitive and selective detection of DON in wheat flour using AuNPs-BP-MWCNTs-COOH and antibodies. The AuNPs-BP-MWCNTs-COOH nanocomposite was prepared via an in situ reduction reaction and ultrasonic-assisted liquid-phase exfoliation. The nanocomposite exhibits a larger surface area, decent stability, excellent electron transfer capability, good protein binding capability and prominent specificity. The plentiful carboxyl group on the nanocomposite can bind to the amino group of the antibody, and AuNPs have an affinity for the sulfhydryl group of the antibody, which makes it feasible for the nanocomposite to load the antibody. The peak currents are plotted against the logarithm of DON concentration from 0.002 to 80 ng mL-1 with a limit of detection (LOD) of 0.5 pg mL-1. This approach establishes an effective label-free immunosensor platform for the detection of DON with high sensitivity and selectivity in various food and agricultural products.


Assuntos
Técnicas Eletroquímicas , Farinha , Ouro , Nanopartículas Metálicas , Tricotecenos , Triticum , Tricotecenos/análise , Tricotecenos/imunologia , Farinha/análise , Triticum/química , Nanopartículas Metálicas/química , Ouro/química , Técnicas Eletroquímicas/métodos , Imunoensaio/métodos , Técnicas Biossensoriais/métodos , Limite de Detecção , Nanotubos de Carbono/química , Contaminação de Alimentos/análise , Nanocompostos/química
10.
Exp Neurol ; 380: 114899, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39059737

RESUMO

Various health issues have emerged due to consuming high-fat diets (HFD), particularly the detrimental impact they have on mitochondrial dynamics and subsequet cognition functions. Specially, mitochondrial fission can serve as an upstream signal in the regulation of cortical inflammation and neural pyroptosis. Our study was designed to verify the existence of neuroinflammation in the pathogenesis of HFD-induced cognitive dysfunction and demonstrated that resveratrol (RSV) attenuated neural deficits via regulation of cortical mitochondrial fission. A total of 50 male Sprague Dawley rats were randomly divided into five groups: control (Cont, 26 weeks on normal rodent diet); high-fat diet (HFD); dietary adjustments (HFD + ND); resveratrol intervention (HFD + R); joint intervention (HFD + ND + R) for 26 weeks. The spatial learning and memory function, spine density, NLRP3 inflammasome associated protein, mRNA and protein expression involved in mitochondrial dynamics and SIRT1/PGC-1α signaling pathway in brain were measured. Furthermore, reactive oxygen species (ROS) accumulation and resultant mitochondrial membrane potential (MMP) alteration in PC12 cells exposed to palmitic acid (PA) or Drp1 inhibitor (Mdivi-1) were detected to reflect mitochondrial function. The findings suggested that prolonged treatment of RSV improved cognitive deficits and neuronal damage induced by HFD, potentially attributed to activation of the SIRT1/PGC-1α axis. We further indicated that the activation of the NLRP3 inflammasome in PA (200 µM) treated PC12 cells could be inhibited by Mdivi-1. More importantly, Mdivi-1 (10 µM) reduced intracellular ROS levels and enhanced MMP by reversing Drp1-mediated aberrant mitochondrial fission. To summarize, those results clearly indicated that a HFD inhibited the SIRT1/PGC-1α pathway, which contributed to an imbalance in mitochondrial dynamics and the onset of NLRP3-mediated pyroptosis. This effect was mitigated by the RSV possibly through triggering the SIRT1/PGC-1α axis, prevented aberrant mitochondrial fission and thus inhibited the activation of the NLRP3 inflammatory pathway.

11.
Nature ; 631(8020): 300-306, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38898282

RESUMO

Graphene-based, high-quality, two-dimensional electronic systems have emerged as a highly tunable platform for studying superconductivity1-21. Specifically, superconductivity has been observed in both electron- and hole-doped twisted graphene moiré systems1-17, whereas in crystalline graphene systems, superconductivity has so far been observed only in hole-doped rhombohedral trilayer graphene (RTG)18 and hole-doped Bernal bilayer graphene (BBG)19-21. Recently, enhanced superconductivity has been demonstrated20,21 in BBG because of the proximity to a monolayer WSe2. Here we report the observation of superconductivity and a series of flavour-symmetry-breaking phases in electron- and hole-doped BBG/WSe2 devices by electrostatic doping. The strength of the observed superconductivity is tunable by applied vertical electric fields. The maximum Berezinskii-Kosterlitz-Thouless transition temperature for the electron- and hole-doped superconductivity is about 210 mK and 400 mK, respectively. Superconductivities emerge only when the applied electric fields drive the BBG electron or hole wavefunctions towards the WSe2 layer, underscoring the importance of the WSe2 layer in the observed superconductivity. The hole-doped superconductivity violates the Pauli paramagnetic limit, consistent with an Ising-like superconductor. By contrast, the electron-doped superconductivity obeys the Pauli limit, although the proximity-induced Ising spin-orbit coupling is also notable in the conduction band. Our findings highlight the rich physics associated with the conduction band in BBG, paving the way for further studies into the superconducting mechanisms of crystalline graphene and the development of superconductor devices based on BBG.

12.
ACS Omega ; 9(24): 26363-26379, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38911801

RESUMO

In tight sandstone reservoirs, diagenesis has a significant impact on the development of reservoirs and pore structures. To clarify the effect of diagenesis on the pore structure of tight sandstone, 12 samples of the Yanchang Formation in the basin were studied based on experiments such as high-pressure mercury intrusion and low-temperature nitrogen adsorption. The diagenetic facies in the study area are divided into two categories: strong cementation facies of carbonate minerals and strong compaction facies of soft component minerals, which are relatively unfavorable diagenetic facies, and stable facies of felsic minerals and strong dissolution facies of feldspar minerals, which are dominant diagenetic facies. The pore structure of the Chang 63 reservoir in the study area has obvious fractal characteristics, with a fractal dimension D 1 greater than D 2 and a greater heterogeneity of large pore throats. Compared to compaction and cementation, dissolution has a stronger controlling effect on the pore structure of reservoirs. In tight sandstone reservoirs with low porosity and permeability, dissolution has a more important impact on reservoir transformation and development. The intensity of different types of diagenesis in the Chang 63 reservoir affects reservoir heterogeneity, and the level of the reservoir heterogeneity affects the complexity of reservoir pore structure. In tight sandstone reservoirs, cementation has a stronger controlling effect on the structural complexity of large pores, while dissolution has a stronger controlling effect on the structural complexity of small pores. The dissolution has a strong control effect on the physical properties of the reservoir. This study provides insights into the relationships among the diagenetic facies, reservoir quality, and pore structure of tight sandstone reservoirs. This study has reference significance for the exploration and development of tight oil in the research area.

13.
Molecules ; 29(11)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38893303

RESUMO

In this study, we designed a novel electrochemical sensor by modifying a glass carbon electrode (GCE) with Pd confined mesoporous carbon hollow nanospheres (Pd/MCHS) for the simultaneous detection of ascorbic acid (AA), dopamine (DA), and uric acid (UA). The structure and morphological characteristics of the Pd/MCHS nanocomposite and the Pd/MCHS/GCE sensor are comprehensively examined using SEM, TEM, XRD and EDX. The electrochemical properties of the prepared sensor are investigated through CV and DPV, which reveal three resolved oxidation peaks for AA, DA, and UA, thereby verifying the simultaneous detection of the three analytes. Benefiting from its tailorable properties, the Pd/MCHS nanocomposite provides a large surface area, rapid electron transfer ability, good catalytic activity, and high conductivity with good electrochemical behavior for the determination of AA, DA, and UA. Under optimized conditions, the Pd/MCHS/GCE sensor exhibited a linear response in the concentration ranges of 300-9000, 2-50, and 20-500 µM for AA, DA, and UA, respectively. The corresponding limit of detection (LOD) values were determined to be 51.03, 0.14, and 4.96 µM, respectively. Moreover, the Pd/MCHS/GCE sensor demonstrated outstanding selectivity, reproducibility, and stability. The recovery percentages of AA, DA, and UA in real samples, including a vitamin C tablet, DA injection, and human urine, range from 99.8-110.9%, 99.04-100.45%, and 98.80-100.49%, respectively. Overall, the proposed sensor can serve as a useful reference for the construction of a high-performance electrochemical sensing platform.


Assuntos
Ácido Ascórbico , Carbono , Dopamina , Técnicas Eletroquímicas , Limite de Detecção , Nanosferas , Paládio , Ácido Úrico , Ácido Ascórbico/análise , Ácido Ascórbico/urina , Ácido Úrico/urina , Ácido Úrico/análise , Dopamina/análise , Dopamina/urina , Nanosferas/química , Técnicas Eletroquímicas/métodos , Carbono/química , Paládio/química , Porosidade , Humanos , Eletrodos , Técnicas Biossensoriais/métodos , Reprodutibilidade dos Testes
14.
Environ Geochem Health ; 46(6): 184, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695941

RESUMO

Excessive fluoride can adversely affect bone mineral density (BMD). Oxidative stress and mitochondrial dysfunction are crucial mechanisms of health damage induced by fluoride. Here, a cross-sectional survey involving 907 Chinese farmers (aged 18-60) was carried out in Tongxu County in 2017, aiming to investigate the significance of mitochondrial DNA copy number (mtDNAcn) and oxidative stress in fluoride-related BMD change. Concentrations of urinary fluoride (UF), serum oxidative stress biomarkers, including total antioxidant capacity (T-AOC), total superoxide dismutase (T-SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA), as well as relative mtDNAcn in peripheral blood were determined. The multivariable linear model and mediation analysis were performed to assess associations between UF, oxidative stress, and relative mtDNAcn with BMD. Results showed that GSH-Px levels increased by 6.98 U/mL [95% confidence interval (CI) 3.41-10.56)] with each 1.0 mg/L increment of UF. After stratification, the T-AOC, relative mtDNAcn, and BMD decreased by 0.04 mmol/L (-0.08 ~ -0.01), 0.29-unit (-0.55 ~ -0.04), and 0.18-unit (-0.33 ~ -0.03) with every 1.0 mg/L elevation of UF in the excessive fluoride group (EFG, adults with UF > 1.6 mg/L), respectively. Furthermore, T-AOC and relative mtDNAcn were favorably related to the BMD in the EFG (ß = 0.82, 95%CI 0.16-1.48 for T-AOC; ß = 0.11, 95%CI 0.02-0.19 for relative mtDNAcn). Mediation analysis showed that relative mtDNAcn and T-AOC mediated 15.4% and 17.1% of the connection between excessive fluoride and reduced BMD, respectively. Findings suggested that excessive fluoride was related to lower BMD in adults, and the decrement of T-AOC and relative mtDNAcn partially mediate this relationship.


Assuntos
Densidade Óssea , DNA Mitocondrial , Fazendeiros , Fluoretos , Estresse Oxidativo , Fluoretos/toxicidade , Humanos , Densidade Óssea/efeitos dos fármacos , Adulto , Pessoa de Meia-Idade , Masculino , Estudos Transversais , Adolescente , China , Adulto Jovem , Feminino , Variações do Número de Cópias de DNA , Exposição Ocupacional/efeitos adversos , Biomarcadores/sangue
15.
Physiol Plant ; 176(3): e14329, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38695156

RESUMO

Although tetraploid wheat has rich genetic variability for cultivar improvement, its physiological mechanisms associated with photosynthetic productivity and resilience under nitrogen (N) deficit stress have not been investigated. In this study, we selected emmer wheat (Kronos, tetraploid), Yangmai 25 (YM25, hexaploid), and Chinese Spring (CS, hexaploid) as materials and investigated the differences in net photosynthetic rate (Pn), carboxylation capacity, electron transfer capacity, photosynthetic product output, and photosynthetic N allocation under normal N (CK) and low N (LN) through hydroponic experiments. Tetraploid emmer wheat (Kronos) had a stronger photosynthetic capacity than hexaploid wheat (YM25, CS) under low N stress, which mainly associated with the higher degree of PSII opening, electron transfer rate, Rubisco content and activity, ATP/ADP ratio, Rubisco activase (Rca) activity and Rubisco activation state, and more leaves N allocation to the photosynthetic apparatus, especially the proportion of N allocation to carboxylation under low N stress. Moreover, Kronos reduced the feedback inhibition of photosynthesis by sucrose accumulation through higher sucrose phosphate synthetase (SPS) activity and triose phosphate utilization rate (VTPU). Overall, Kronos could allocate more N to the photosynthetic components to improve Rubisco content and activity to maintain photosynthetic capacity under low N stress while enhancing triose phosphate output to reduce feedback inhibition of photosynthesis. This study reveals the physiological mechanisms of emmer wheat that maintain the photosynthetic capacity under low N stress, which will provide indispensable germplasm resources for elite low-N-tolerant wheat improvement and breeding.


Assuntos
Nitrogênio , Fotossíntese , Ribulose-Bifosfato Carboxilase , Triticum , Fotossíntese/fisiologia , Triticum/fisiologia , Triticum/genética , Triticum/metabolismo , Nitrogênio/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo , Estresse Fisiológico , Folhas de Planta/fisiologia , Folhas de Planta/metabolismo , Adaptação Fisiológica , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Clorofila/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Glucosiltransferases/metabolismo , Glucosiltransferases/genética
16.
Heliyon ; 10(9): e30316, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38774107

RESUMO

In the post-epidemic era, public panic has emerged as a highly significant secondary disaster, necessitating an urgent enhancement of emergency management capabilities by governments at all levels. In order to ensure a robust assessment of the government's ability to manage public panic, it is crucial to effectively address the influence of uncertain and ambiguous factors associated with such scenarios. This paper proposes a governmental public panic emergency management capability assessment method based on fuzzy Petri nets. By analyzing the factors influencing public panic across the four evolutionary stages, namely gestation, outbreak, diffusion, and fading, we establish a hierarchical evaluation index system for assessing emergency management capabilities. Additionally, we develop a range of multi-scenario emergency management strategies. To address the challenges posed by uncertainty, randomness, fuzziness, and insufficient statistical data within the assessment index system, we introduce fuzzy Petri nets and fuzzy reasoning rules to evaluate the emergency management capability of the assessment system and derive the optimal emergency management strategy. According to example simulations, the effectiveness and practicality of models and rules constructed using fuzzy Petri nets are demonstrated, highlighting their superiority over traditional assessment methods. This comprehensive approach equips the government with a versatile toolkit for effectively managing public panic emergencies.

18.
Mol Pharm ; 21(5): 2327-2339, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38576375

RESUMO

In the present study, we investigated the role of lipid composition of camptothecin (CPT)-loaded liposomes (CPT-Lips) to adjust their residence time, drug distribution, and therefore the toxicities and antitumor activity. The CPT was loaded into liposomes using a click drug loading method, which utilized liposomes preloaded with GSH and then exposed to CPT-maleimide. The method produced CPT-Lips with a high encapsulation efficiency (>95%) and sustained drug release. It is shown that the residence times of CPT-Lips in the body were highly dependent on lipid compositions with an order of non-PEGylated liposomes of unsaturated lipids < non-PEGylated liposomes of saturated lipids < PEGylated liposomes of saturated lipids. Interestingly, the fast clearance of CPT-Lips resulted in significantly decreased toxicities but did not cause a significant decrease in their in vivo antitumor activity. These results suggested that the lipid composition could effectively adjust the residence time of CPT-Lips in the body and further optimize their therapeutic index, which would guide the development of a liposomal formulation of CPT.


Assuntos
Camptotecina , Lipídeos , Lipossomos , Camptotecina/química , Camptotecina/administração & dosagem , Camptotecina/farmacocinética , Camptotecina/farmacologia , Lipossomos/química , Animais , Camundongos , Lipídeos/química , Humanos , Liberação Controlada de Fármacos , Sistemas de Liberação de Medicamentos/métodos , Polietilenoglicóis/química , Linhagem Celular Tumoral , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacocinética , Antineoplásicos Fitogênicos/farmacologia , Feminino , Química Click/métodos , Camundongos Endogâmicos BALB C
19.
Planta ; 259(5): 107, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38554244

RESUMO

MAIN CONCLUSION: Early-stage low nitrogen priming promotes root growth and delays leaf senescence through gene expression, enhancing nitrogen absorption and assimilation in wheat seedlings, thereby alleviating growth inhibition under nitrogen deficit stress and supporting normal seedling development. Verifying the strategies to reduce the amount of nitrogen (N) fertilizer while maintaining high crop yields is important for improving crop N use efficiency (NUE) and protecting the environment. To determine whether low N (LN) priming (LNP) can alleviate the impact of N-deficit stress on the growth of wheat seedlings and improve their tolerance to N-deficit stress, we conducted hydroponic experiments using two wheat cultivars, Yangmai 158 (YM158, LN tolerant) and Zaoyangmai (ZYM, LN sensitive) to study the effects of LNP on wheat seedlings under N-deficit stress. N-deficit stress decreased the plant dry weight, leaf area, and leaf N content (LNC), while LNP could significantly reduce this reduction. Distinct sensitivities to N-deficit stress were observed between the wheat cultivars, with ZYM showing an early decrease in leaf N content compared to YM158, which exhibited a late-stage reduction. LNP promoted root growth, expanded N uptake area, and upregulated the expression of TaNRT1.1, TaNRT2.1, and TaNRT2.2 in wheat seedlings, suggesting that LNP can enhance root N uptake capacity to increase N accumulation in plants. In addition, LNP improved the activity of glutamine synthase (GS) to enhance the capacity of N assimilation of plants. The relative expression of TaGS1 in the lower leaves of priming and stress (PS) was lower than that of no priming and stress (NS) after LNP, indicating that the rate of N transfer from the lower leaves to the upper leaves became slower after LNP, which alleviated the senescence of the lower leaves. The relative expression of TaGS2 was significantly increased, which might be related to the enhanced photorespiratory ammonia assimilation capacity after LNP, which reduced the N loss and maintained higher LNC. Therefore, LNP in the early stage can improve the N absorption and assimilation ability and maintain the normal N supply to alleviate the inhibition of N-deficit stress in wheat seedlings.


Assuntos
Plântula , Tetrazóis , Tiazóis , Triticum , Triticum/genética , Nitrogênio/metabolismo , Plantas/metabolismo
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