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1.
Int J Mol Sci ; 25(2)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38255880

RESUMO

Auxin Response Factors (ARFs) mediate auxin signaling and govern diverse biological processes. However, a comprehensive analysis of the ARF gene family and identification of their key regulatory functions have not been conducted in Melastoma dodecandrum, leading to a weak understanding of further use and development for this functional shrub. In this study, we successfully identified a total of 27 members of the ARF gene family in M. dodecandrum and classified them into Class I-III. Class II-III showed more significant gene duplication than Class I, especially for MedARF16s. According to the prediction of cis-regulatory elements, the AP2/ERF, BHLH, and bZIP transcription factor families may serve as regulatory factors controlling the transcriptional pre-initiation expression of MedARF. Analysis of miRNA editing sites reveals that miR160 may play a regulatory role in the post-transcriptional expression of MeARF. Expression profiles revealed that more than half of the MedARFs exhibited high expression levels in the stem compared to other organs. While there are some specific genes expressed only in flowers, it is noteworthy that MedARF16s, MedARF7A, and MedARF9B, which are highly expressed in stems, also demonstrate high expressions in other organs of M. dodecandrum. Further hormone treatment experiments revealed that these MedARFs were sensitive to auxin changes, with MedARF6C and MedARF7A showing significant and rapid changes in expression upon increasing exogenous auxin. In brief, our findings suggest a crucial role in regulating plant growth and development in M. dodecandrum by responding to changes in auxin. These results can provide a theoretical basis for future molecular breeding in Myrtaceae.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica , Melastomataceae , Embaralhamento de DNA , Flores , Duplicação Gênica , Ácidos Indolacéticos/farmacologia
2.
Int J Mol Sci ; 25(2)2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38256078

RESUMO

Heat shock factors (HSFs) are the key regulators of heat stress responses and play pivotal roles in tissue development and the temperature-induced regulation of secondary metabolites. In order to elucidate the roles of HSFs in Cymbidium ensifolium, we conducted a genome-wide identification of CeHSF genes and predicted their functions based on their structural features and splicing patterns. Our results revealed 22 HSF family members, with each gene containing more than one intron. According to phylogenetic analysis, 59.1% of HSFs were grouped into the A subfamily, while subfamily HSFC contained only two HSFs. And the HSF gene families were differentiated evolutionarily between plant species. Two tandem repeats were found on Chr02, and two segmental duplication pairs were observed on Chr12, Chr17, and Chr19; this provided evidence for whole-genome duplication (WGD) events in C. ensifolium. The core region of the promoter in most CeHSF genes contained cis-acting elements such as AP2/ERF and bHLH, which were associated with plant growth, development, and stress responses. Except for CeHSF11, 14, and 19, each of the remaining CeHSFs contained at least one miRNA binding site. This included binding sites for miR156, miR393, and miR319, which were responsive to temperature and other stresses. The HSF gene family exhibited significant tissue specificity in both vegetative and floral organs of C. ensifolium. CeHSF13 and CeHSF15 showed relatively significant expression in flowers compared to other genes. During flower development, CeHSF15 exhibited markedly elevated expression in the early stages of flower opening, implicating critical regulatory functions in organ development and floral scent-related regulations. During the poikilothermic treatment, CeHSF14 was upregulated over 200-fold after 6 h of heat treatment. CeHSF13 and CeHSF14 showed the highest expression at 6 h of low temperature, while the expression of CeHSF15 and CeHSF21 continuously decreased at a low temperature. The expression patterns of CeHSFs further confirmed their role in responding to temperature stress. Our study may help reveal the important roles of HSFs in plant development and metabolic regulation and show insight for the further molecular design breeding of C. ensifolium.


Assuntos
Temperatura Baixa , Resposta ao Choque Térmico , Temperatura , Filogenia , Resposta ao Choque Térmico/genética , Sítios de Ligação
3.
Polymers (Basel) ; 16(2)2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38257028

RESUMO

Soft materials bearing rigid, lightweight, and vibration-dampening properties offer distinct advantages over traditional wooden and metal-based fillings for spent fuel transport casks, due to their low density, tunable structure, excellent mechanical properties, and ease of processing. In this study, a novel type of rigid polyurethane foam is prepared using a conventional polycondensation reaction between isocyanate and hydroxy groups. Moreover, the density and size of the pores in these foams are precisely controlled through simultaneous gas generation. The as-prepared polyurethane exhibits high thermal stability exceeding 185 °C. Lifetime predictions based on thermal testing indicate that these polyurethane foams could last up to over 60 years, which is double the lifetime of conventional materials of about 30 years. Due to their occlusive structure, the mechanical properties of these polymeric materials meet the design standards for spent fuel transport casks, with maximum compression and tensile stresses of 6.89 and 1.37 MPa, respectively, at a testing temperature of -40 °C. In addition, these polymers exhibit effective flame retardancy; combustion ceased within 2 s after removal of the ignition source. All in all, this study provides a simple strategy for preparing rigid polymeric foams, presenting them as promising prospects for application in spent fuel transport casks.

5.
Materials (Basel) ; 16(11)2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37297285

RESUMO

In sand casting, gas porosity is a common defect that can result in decreased strength, leakage, rough surfaces, or other problems. Although the forming mechanism is very complicated, gas release from sand cores is often a significant contributor to the formation of gas porosity defects. Therefore, studying the gas release behavior of sand cores is crucial to solving this problem. Current research on the gas release behavior of sand cores mainly focuses on parameters such as gas permeability and gas generation properties, through experimental measurement and numerical simulation methods. However, accurately reflecting the gas generation situation in the actual casting process is difficult, and there are certain limitations. To achieve the actual casting condition, a sand core was designed and enclosed inside a casting. The core print was extended to the sand mold surface, with two types of core prints: hollow and dense. Pressure and airflow speed sensors were installed on the exposed surface of the core print to investigate the burn-off of the binder of the 3D-printed furan resin quartz sand cores. The experimental results showed that the gas generation rate was high in the initial stage of the burn-off process. The gas pressure quickly reached its peak in the initial stage and then decreased rapidly. The exhaust speed of the dense type of core print was 1 m/s, lasting for 500 s. The pressure peak of the hollow-type sand core was 1.09 kPa, and the exhaust speed peak was 1.89 m/s. The binder can be sufficiently burned off for the location surrounding the casting and the crack-affected area, so the burnt sand appears white, while the burnt core appears black due to insufficient burning of the binder because of isolation from the air. The gas generated by the burnt resin sand in contact with air was 30.7% less than that generated by the burnt resin sand insulated from the air.

6.
Zhen Ci Yan Jiu ; 47(12): 1107-12, 2022 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-36571227

RESUMO

OBJECTIVE: To observe the clinical efficacy of shallow-needle therapy combined with estazolam on insomnia differentiated as liver stagnation transforming into fire and its effect on adrenocorticotropic hormone (ACTH) and cortisol (CORT), so as to explore the mechanism of this combined treatment. METHODS: A total of 119 patients with insomnia of liver stagnation transforming into fire pattern were randomly divided into shallow-needle therapy group (n=40), medication group (n=39), and shallow-needle therapy combined with medication group (combined therapy group,n=40). In the shallow-needle therapy group, the patients were treated with finger pressure and operation with shallow stimulating at Zhenjing (Dong's extra point, sedative point) and Taichong (LR3). In the medication group, the patients were administered with estazolam (1 mg) orally. In the combined therapy group, both shallow-needle therapy and medication were administered. The treatment was given once daily in each group, 10 days as one session of treatment and 2 sessions were required. Before and after the treatment, Pittsburgh sleep quality index scale (PSQI) and Self-rating anxiety scale (SAS) were used to assess sleep and anxiety status. ELISA was used to detect the contents of ACTH and CORT in plasma. The clinical efficacy was evaluated in each group. RESULTS: In within-group comparison, PSQI scores, SAS scores and the concentrations of ACTH and CORT in plasma were all decreased (P<0.05) after treatment for the patients of three groups. After treatment, the total PSQI score, the score for sleep latency, sleep duration and daytime dysfunction, as well as SAS score in the combined therapy group were all lower than those of the shallow-needle therapy group (P<0.05); the total PSQI score, the score for sleep duration and sleep efficiency, as well as SAS score were lower when compared with the medication group (P<0.05). The total effective rates were 87.50% (35/40), 82.05% (32/39) and 95.00% (38/40) in the shallow-needle therapy group, the medication group and the combined therapy group, respectively. The total effective rate in the combined therapy group was higher than those of the shallow-needle therapy group and the medication group separately (P<0.05). CONCLUSION: Shallow-needle therapy combined with estazolam is effective on insomnia of liver stagnation transforming into fire pattern, and its underlying effect mechanism is related to the reduction of plasma ACTH and CORT levels.


Assuntos
Terapia por Acupuntura , Distúrbios do Início e da Manutenção do Sono , Humanos , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Estazolam/uso terapêutico , Pontos de Acupuntura , Resultado do Tratamento , Fígado , Hormônio Adrenocorticotrópico , Hidrocortisona
7.
Zhongguo Zhong Yao Za Zhi ; 46(24): 6435-6446, 2021 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-34994136

RESUMO

A sensitive and efficient method was established and validated for qualitative and quantitative analysis of total alkaloids from the extract of Eurycoma longifolia by high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(HPLC-Q-TOF-MS) combined with ultra-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry(UPLC-QQQ-MS/MS). The HPLC-Q-TOF-MS conditions are as follows: Welch Ultimate XB-C_(18) column(4.6 mm×250 mm, 5 µm) with acetonitrile(containing 0.1% formic acid)-0.1% formic acid in water as mobile phase for gradient elution. The UPLC-QQQ-MS/MS conditions are as below: Agilent Eclipse Plus C_(18) column(2.1 mm×50 mm, 1.8 µm) with acetonitrile(containing 0.1% formic acid) and 0.1% formic acid in water as mobile phase for gradient elution. MS data were collected by electrospray ionization in positive ion mode. According to the comparison with reference standards and the accurate masses of molecules, a total of 17 alkaloids in E. longifolia extract were identified by HPLC-Q-TOF-MS. The UPLC-QQQ-MS/MS quantitative analysis result of 3 alkaloids showed that the linear ranges of them were good(r≥0.999 7) and the overall recoveries ranged from 108.8%-110.2%, with RSDs of 2.9%-5.3%. The method is accurate, reliable, and efficient, which can comprehensively reflect the constituents and content of alkaloids in E. longifolia. The result can serve as a reference for further elucidating its therapeutic material basis and quality control.


Assuntos
Alcaloides , Eurycoma , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Espectrometria de Massas em Tandem
8.
Cell Physiol Biochem ; 33(2): 375-88, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24556579

RESUMO

BACKGROUND/AIMS: The effects of glycyrrhizin treatment in lung cancer remain undetermined, despite extensive studies of the anti-tumor activities of glycyrrhizin. METHODS: Lung adenocarcinoma A549 and NCI-H23 cell lines were used in this study. Cell growth was examined by MTS assays, while apoptosis and cell cycle were determined by flow cytometric analysis. Both real-time PCR and western blotting were used to examine the expression levels of thromboxane synthase (TxAS), and TxAS activity was measured using EIA detection of the biosynthesis of TxA2. TxAS was overexpressed in NCI-H23 cells by transfection with TxAS cDNA, while TxAS was inhibited by transfection with TxAS siRNA in A549 cells. For the mouse model of lung adenocarcinoma, the effects of glycyrrhizin on tumor growth were analyzed by western blot evaluation of TxAS, PTEN and survivin. TxAS activity was determined by EIA assay. RESULTS: Glycyrrhizin suppressed cell growth in A549 cells, but not in NCI-H23 cells, by induction of apoptosis. TxAS was overexpressed in A549 cells, but the TxAS levels in NCI-H23 cells were minimal. Moreover, TxAS expression and activity were suppressed by glycyrrhizin. Glycyrrhizin had no additive effects with TxAS siRNA knockdown in suppressing A549 cell growth, whereas it completely suppressed cell growth of NCI-H23 cells transfected with TxAS cDNA. These results were further confirmed by the in vivo study. CONCLUSION: Our study suggests that the anti-tumor effect of glycyrrhizin in lung adenocarcinoma is, at least in part, TxAS-dependent. Therefore, glycyrrhizin is a promising anti-cancer agent for the treatment of lung adenocarcinoma.


Assuntos
Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Ácido Glicirrízico/farmacologia , Neoplasias Pulmonares , Proteínas de Neoplasias/metabolismo , Tromboxano-A Sintase/metabolismo , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Anti-Inflamatórios/farmacologia , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Tromboxano-A Sintase/genética
9.
J Chromatogr A ; 1217(36): 5687-92, 2010 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-20688334

RESUMO

A method of using high-speed counter-current chromatography (HSCCC) was established for preparative isolation and purification of antimycin A components from antimycin fermentation broth. Six antimycin A components were successfully purified for the first time by HSCCC with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (5:2:4:1, by volume). Total of 20mg antimycin A(4)(a or b), 25mg antimycin A(3)(a or b), 21mg antimycin A(8)(a or b), 34mg antimycin A(2)(a or b), 26mg antimycin A(1)(a or b) and 34mg antimycin A(1)(a or b) with the purities of 93.2, 98.6, 96.2, 94.1, 94.9 and 96.7%, respectively, determined by high-performance liquid chromatography (HPLC), were yielded from 200mg crude sample only in one HSCCC run.


Assuntos
Antimicina A/química , Distribuição Contracorrente/métodos , Fermentação , Acetatos/química , Antimicina A/isolamento & purificação , Antimicina A/metabolismo , Reatores Biológicos , Meios de Cultivo Condicionados/química , Hexanos/química , Metanol/química , Streptomyces/metabolismo , Água/química
10.
J Chromatogr A ; 1216(22): 4668-72, 2009 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-19394946

RESUMO

Three macrolide antibiotic components - ascomycin, tacrolimus and dihydrotacrolimus - were separated and purified by silver ion high-speed counter-current chromatography (HSCCC). The solvent system consisted of n-hexane-tert-butyl methyl ether-methanol-water (1:3:6:5, v/v) and silver nitrate (0.10mol/l). The silver ion acted as a pi-complexing agent with tacrolimus because of its extra side double bond compared with ascomycin and dihydrotacrolimus. This complexation modified the partition coefficient values and the separation factors of the three components. As a result, ascomycin, tacrolimus and dihydrotacrolimus were purified from 150mg extracted crude sample with purities of 97.6%, 98.7% and 96.5%, respectively, and yields over 80% (including their tautomers). These results cannot be achieved with the same solvent system but without the addition of silver ion.


Assuntos
Antibacterianos/isolamento & purificação , Distribuição Contracorrente/métodos , Íons/química , Macrolídeos/isolamento & purificação , Prata/química , Antibacterianos/química , Macrolídeos/química
11.
Zhonghua Nan Ke Xue ; 9(5): 367-9, 2003 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-14513648

RESUMO

OBJECTIVE: To observe the effect of low-dose triptorelin in later luteal phase on pituitary down-regulation for patients undergoing IVF-ET. METHODS: One hundred and twenty patients were randomly divided into 2 groups(A and B). In group A, the patients were treated with triptorelin of 0.1 mg subcutaneously daily started on day 21 of menstrual cycle for 7 days. In group B, the patients were treated with long protocol of Buserelin intranasal spray. Comparisons were made between the groups in serum concentrations of FSH, LH, E2, T, PRL and P on the third day (D3) of superovulation cycle and on the day of hCG administration, highly purified follicle-stimulating hormone (HP) dosages, and so on. RESULTS: In group A, mean serum LH level on D3 and the day of hCG was (1.55 +/- 0.99) U/L and (2.70 +/- 1.45) U/L, E2 was (85.66 +/- 13.13) pmol/L and (5,451.31 +/- 1,900.61) pmol/L, respectively, significantly lower than those of group B (P < 0.001; P < 0.01; P < 0.05; P < 0.001). Mean HP(75 IU/Amp) dosage per treatment cycle in group A was 28.20 +/- 11.03 ampoules, significantly higher than 22.30 +/- 6.40 ampoules in group B(P < 0.001). CONCLUSIONS: Low-dose triptorelin in later luteal phase is effective for down-regulation of pituitary and produces more suppression on endogenous LH in pituitary than Buserelin long protocol.


Assuntos
Transferência Embrionária , Fertilização in vitro , Luteolíticos/administração & dosagem , Hipófise/fisiologia , Pamoato de Triptorrelina/administração & dosagem , Adulto , Regulação para Baixo , Estradiol/sangue , Feminino , Humanos , Injeções Subcutâneas , Hormônio Luteinizante/sangue , Hipófise/efeitos dos fármacos
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