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1.
Front Oncol ; 14: 1344290, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38469234

RESUMO

Ferroptosis differs from traditional cell death mechanisms like apoptosis, necrosis, and autophagy, primarily due to its reliance on iron metabolism and the loss of glutathione peroxidase activity, leading to lipid peroxidation and cell death. The dysregulation of iron metabolism is a hallmark of various cancers, contributing to tumor progression, metastasis, and notably, drug resistance. The acquisition of mesenchymal characteristics by epithelial cells is known as Epithelial-Mesenchymal Transition (EMT), a biological process intricately linked to cancer development, promoting traits such as invasiveness, metastasis, and resistance to therapeutic interventions. EMT plays a pivotal role in cancer progression and contributes significantly to the complex dynamics of carcinogenesis. Research findings indicate that mesenchymal cancer cells exhibit greater susceptibility to ferroptosis compared to their epithelial counterparts. The induction of ferroptosis becomes more effective in eliminating drug-resistant cancer cells during the process of EMT. The interplay between ferroptosis and EMT, a process where epithelial cells transform into mobile mesenchymal cells, is crucial in understanding cancer progression. EMT is associated with increased cancer metastasis and drug resistance. The review delves into how ferroptosis and EMT influence each other, highlighting the role of key proteins like GPX4, which protects against lipid peroxidation, and its inhibition can induce ferroptosis. Conversely, increased GPX4 expression is linked to heightened resistance to ferroptosis in cancer cells. Moreover, the review discusses the implications of EMT-induced transcription factors such as Snail, Zeb1, and Twist in modulating the sensitivity of tumor cells to ferroptosis, thereby affecting drug resistance and cancer treatment outcomes. Targeting the ferroptosis pathway offers a promising therapeutic strategy, particularly for tumors resistant to conventional treatments. The induction of ferroptosis in these cells could potentially overcome drug resistance. However, translating these findings into clinical practice presents challenges, including understanding the precise mechanisms of ferroptosis induction, identifying predictive biomarkers, and optimizing combination therapies. The review underscores the need for further research to unravel the complex interactions between ferroptosis, EMT, and drug resistance in cancer. This could lead to the development of more effective, targeted cancer treatments, particularly for drug-resistant tumors, offering new hope in cancer therapeutics.

2.
Front Plant Sci ; 14: 1266791, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023921

RESUMO

The canopies of high stalk crops, such as maize, intersect the rows at the later stages of growth, making conventional sprayers unable to enter the field for spraying. Air-assisted sprayers are often used to improve the deposition of droplets inside the canopy. In this study, the sprayer structure, the air-assisted system, and the spraying system were designed. The air-assisted conveyor system characteristics were numerically analyzed, and the wind-field distribution was tested. The wind-field distribution results showed that the near-ground wind speed exceeded 5 m s-1 in the sampling interval from 10 to 35 metres. The wind field covered a concentrated spatial area with a downward pressure trend, resulting in better drift resistance and penetration. Field tests for droplet distribution were conducted at three maize heights to verify the powerful air-assisted sprayer's technical performance and working quality. The test results showed that the droplet deposition and coverage decreased gradually along the range direction, and the top layer had the highest deposition and coverage across the canopy. The upper canopy of 0 to 12 metres range demonstrated a greater extent of coverage and deposition. The peak deposition area expanded from 9 to 33 metres in the lower canopy, with an average value of 3.77 µg cm-2. The droplet coverage within the 30 to 60 metres range only amounted to 15% to 18% of the total coverage.

3.
Zhongguo Zhong Yao Za Zhi ; 37(7): 934-6, 2012 Apr.
Artigo em Zh | MEDLINE | ID: mdl-22792792

RESUMO

OBJECTIVE: To apply the membrane separation process in the concentration process of Chuanxiong Chatiao granules and to lay the foundation for its industrialized application. METHOD: The type of membrane, the optimal pressure, the optimal temperature and the optimal detergent were selected by the single factor method. A comparative study was conducted between qualities of extracts from Chuanxiong Chatiao granules by new and traditional processes. RESULT: The type of membrane was determined to be SMN-130A2350054. The optimal pressure was 1.7 MPa. The optimal temperature was 36 degrees C and the optimal detergent was 1% sodium polyphosphate. The qualities of extracts from Chuanxiong Chatiao granules by new and traditional processes showed no difference. CONCLUSION: The selected membrane separation process can effectively achieve concentration and save energy. The extracts from Chuanxiong Chatiao granules by the new process show no difference with traditional processes. Therefore, it provides basis for the industrialized application of Chuanxiong Chatiao granules.


Assuntos
Medicamentos de Ervas Chinesas/química , Tecnologia Farmacêutica/métodos
4.
Sci Total Environ ; 812: 152558, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34952086

RESUMO

As one of three top-priority eutrophic lakes in China, Dianchi Lake has received national attention due to its severe eutrophication in recent decades. Meteorological factors are the main factors driving the formation and persistence of algae blooms. In addition, meteorological variation-induced algal blooms usually have a hysteresis effect. However, there have been few quantitative studies on this hysteresis effect. In the present study, Landsat images were used to extract the dynamic characteristics of changes in algal blooms in Dianchi Lake from 1988 to 2020. The hysteresis effect of meteorological factors driving algal blooms was studied by employing the modified lag-correlation method. The results showed that the algal blooms in Dianchi Lake were most severe between 1998 and 2008. During the periods of algal blooms, the values of air temperature (AT) and precipitation (PP) were significantly higher, while those wind velocity (WV) and sunshine duration (SSD) were obviously lower, than the corresponding annual mean values. AT and PP were significantly positively correlated with algal bloom factors in both the formation and persistence stages of algal blooms, while SSD and WV both promoted their regression, but these effects were less significant in the persistence period than in the formation period. Moreover, rainfall led to a decrease in SSD and WV, indirectly contributing to algal blooms. Furthermore, AT, PP and SSD are the main factors impacting the duration of persistent blooms. The time periods during which each meteorological factor was most influential were as follows: 1) AT - 25-30 days before the maximum bloom. 2) PP - within the first 10 days before the maximum bloom. 3) Both SSD and WV - 15-20 days before the maximum bloom. The results of this study support the prediction of algal blooms in Dianchi Lake.


Assuntos
Monitoramento Ambiental , Lagos , China , Eutrofização , Vento
5.
Mitochondrial DNA B Resour ; 6(12): 3501-3502, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869891

RESUMO

The complete chloroplast genome of Trollius macropetalus was sequenced in this study. It has a cyclic tetrad structure typical of angiosperms. The total length is 160,094 bp, including a large single copy region (LSC) with a length of 88,555 bp, a small single copy region (SSC) with a length of 18,291 bp and two equal-length inverted repeat regions (IRA/IRB) with a length of 26,624 bp. It encodes a total of 137 genes, including 87 protein-coding genes, 42 tRNA genes, and 8 rRNA genes, with a CG content of 38.03%.

6.
J Mol Model ; 22(11): 277, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27787776

RESUMO

The ground state and excited state properties of three coumarin dyes, ZCJ1, ZCJ2 and ZCJ3, including ground state structures, energy levels, absorption spectra and driving forces of electron injection, were investigated via density functional theory (DFT) and time-dependent density functional theory (TD-DFT). In addition, five new molecules ZCJ3-1, ZCJ3-2, ZCJ3-3, ZCJ3-4 and ZCJ3-5 were designed through the introduction of a -CN group into molecule ZCJ3. The ground state and excited state properties of the five designed molecules were also calculated and compared with that of the original molecule, aiming to investigate the effect of different position of -CN groups on the optical and electrical properties of dye molecules. Moreover, the external electric field was taken into account. The results indicated that all three original molecules have better absorption within the visible-light range, and the molecule with a thiophene-thiophene conjugated bridge enables a red shift of the absorption spectrum. The molecule with a thiophene-benzene ring conjugated bridge enables the increase of driving force of electron injection. The energy levels, spectra and driving force of electron injection for the designed molecules are discussed in terms of studying their potential utility in dye-sensitized solar cells.

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