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1.
Sci Rep ; 13(1): 9842, 2023 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-37330532

RESUMO

In this study, a sump in the Xingdong coal mine (buried at a depth of over 1200 m) was used to analyze the surrounding rock's stability and control technology. Under the combined influences of various complex conditions, such as the burial depth of over 1200 m, ultra-high ground stress, and location under the goaf, the sump support became extremely difficult, severely restricting the efficient production of the mine. The overall pressure-relief mechanisms and degree of the sump surrounding the rock environment under the goaf were studied, and the rationality of the sump location was verified through numerical simulations and field tests. A more effective support scheme was proposed based on the deformation characteristics and failure mechanisms of the temporary sump-surrounding rock under the supporting conditions. The combined control technology employed the lengthened strong anchor bolts (cables), full-section concrete-filled steel tubular supports, and pouring full-section reinforced concrete and full-section long-hole grouting reinforcement. The field test results showed that after adopting the new support scheme, the sump-surrounding rock tended to be stable after three months. The sump roof subsidence amount, floor heave amount, and convergence of the two sidewalls of the sump were 17.2-19.2 mm, 13.9-16.5 mm, and 23.2-27.9 mm, respectively, thus satisfying the application requirements. This study provides an essential reference for deep-mine roadway support under a complex high-ground-stress environment.


Assuntos
Asma , Doença Pulmonar Obstrutiva Crônica , Humanos , Sepultamento , Reforço Psicológico , Tecnologia
2.
Mycobiology ; 51(3): 169-177, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37359953

RESUMO

To further explore the molecular mechanism of triterpenoid biosynthesis and acquire high-value strain of Sanghuangporus baumii, the Agrobacterium tumefaciens-mediated transformation (ATMT) system was studied. The key triterpenoid biosynthesis-associated gene isopentenyl diphosphate isomerase (IDI) was transformed into S. baumii by ATMT system. Then, the qRT-PCR technique was used to analyze gene transcript level, and the widely targeted metabolomics was used to investigate individual triterpenoid content. Total triterpenoid content and anti-oxidant activity were determined by spectrophotometer. In this study, we for the first time established an efficient ATMT system and transferred the IDI gene into S. baumii. Relative to the wild-type (WT) strain, the IDI-transformant (IT) strain showed significantly higher transcript levels of IDI and total triterpenoid content. We then investigated individual triterpenoids in S. baumii, which led to the identification of 10 distinct triterpenoids. The contents of individual triterpenoids produced by the IT2 strain were 1.76-10.03 times higher than those produced by the WT strain. The triterpenoid production showed a significant positive correlation with the IDI gene expression. Besides, IT2 strain showed better anti-oxidant activity. The findings provide valuable information about the biosynthetic pathway of triterpenoids and provide a strategy for cultivating high-value S. baumii strains.

3.
Molecules ; 28(5)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36903461

RESUMO

The rhizome of Atractylodes lancea (RAL) is a well-known Chinese herbal medicine (CHM) that has been applied in clinical settings for thousands of years. In the past two decades, cultivated RAL has gradually replaced wild RAL and become mainstream in clinical practice. The quality of CHM is significantly influenced by its geographical origin. To date, limited studies have compared the composition of cultivated RAL from different geographical origins. As essential oil is the primary active component of RAL, a strategy combining gas chromatography-mass spectrometry (GC-MS) and chemical pattern recognition was first applied to compare the essential oil of RAL (RALO) from different regions in China. Total ion chromatography (TIC) revealed that RALO from different origins had a similar composition; however, the relative content of the main compounds varied significantly. In addition, 26 samples obtained from various regions were divided into three categories by hierarchical cluster analysis (HCA) and principal component analysis (PCA). Combined with the geographical location and chemical composition analysis, the producing regions of RAL were classified into three areas. The main compounds of RALO vary depending on the production areas. Furthermore, a one-way analysis of variance (ANOVA) revealed that there were significant differences in six compounds, including modephene, caryophyllene, γ-elemene, atractylon, hinesol, and atractylodin, between the three areas. Hinesol, atractylon, and ß-eudesmol were selected as the potential markers for distinguishing different areas by orthogonal partial least squares discriminant analysis (OPLS-DA). In conclusion, by combining GC-MS with chemical pattern recognition analysis, this research has identified the chemical variations across various producing areas and developed an effective method for geographic origin tracking of cultivated RAL based on essential oils.


Assuntos
Atractylodes , Óleos Voláteis , Óleos Voláteis/química , Cromatografia Gasosa-Espectrometria de Massas , Atractylodes/química , Rizoma/química
4.
Int J Mol Sci ; 24(5)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36901784

RESUMO

The external electric field (E-field), which is an important stimulus, can change the decomposition mechanism and sensitivity of energetic materials. As a result, understanding the response of energetic materials to external E-fields is critical for their safe use. Motivated by recent experiments and theories, the two-dimensional infrared (2D IR) spectra of 3,4-bis (3-nitrofurazan-4-yl) furoxan (DNTF), which has a high energy, a low melting point, and comprehensive properties, were theoretically investigated. Cross-peaks were observed in 2D IR spectra under different E-fields, which demonstrated an intermolecular vibration energy transfer; the furazan ring vibration was found to play an important role in the analysis of vibration energy distribution and was extended over several DNTF molecules. Measurements of the non-covalent interactions, with the support of the 2D IR spectra, indicated that there were obvious non-covalent interactions among different DNTF molecules, which resulted from the conjugation of the furoxan ring and the furazan ring; the direction of the E-field also had a significant influence on the strength of the weak interactions. Furthermore, the calculation of the Laplacian bond order, which characterized the C-NO2 bonds as trigger bonds, predicted that the E-fields could change the thermal decomposition process of DNTF while the positive E-field facilitates the breakdown of the C-NO2 in DNTFⅣ molecules. Our work provides new insights into the relationship between the E-field and the intermolecular vibration energy transfer and decomposition mechanism of the DNTF system.


Assuntos
Dióxido de Nitrogênio , Vibração , Espectrofotometria Infravermelho , Transferência de Energia
5.
J Fungi (Basel) ; 8(9)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36135614

RESUMO

Triterpenoids are secondary metabolites produced by the fungus Sanghuangporus baumii that have important pharmacological activities. However, the yield of triterpenoids is low and cannot meet market demand. Here, we treated S. baumii with several concentrations of MeJA (methyl jasmonate) and found that the total triterpenoid content was highest (23.31 mg/g) when the MeJA concentration was 250 µmol/L. qRT-PCR was used to quantify the transcription of five key genes involved in triterpenoid biosynthesis. The results showed that the relative transcription of most genes increased with increasing MeJA concentration, indicating that MeJA is a potent inducer of triterpenoid biosynthesis in S. baumii. To further explore whether other terpenoid biosynthesis pathways are also involved in the accumulation of triterpenoids induced by MeJA, we measured the contents of cis-Zeatin (cZ), gibberellins (GAs), and the transcript levels of related biosynthesis genes. We found that MeJA significantly inhibited the biosynthesis of cZ, GAs, and the transcription of related genes. The repressive effects of MeJA on cZ and GA accumulation were further confirmed by growth rate and biomass assays. In conclusion, our study provides an effective method to enhance the triterpenoid content of S. baumii, and also provides novel insights into the mechanism of MeJA-induced triterpenoid biosynthesis.

6.
J Fungi (Basel) ; 8(7)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35887404

RESUMO

Sanghuangporus baumii is a traditional medicinal fungus that produces pharmacological terpenoids, but natural resources are insufficient for applications, and its growth and development mechanisms are poorly understood. Combining metabolomic and transcriptomic analyses, we found four terpenoid hormones and a central gene, isopentenyl diphosphate isomerase (IDI), involved in growth and development. Additionally, an exogenous hormone test was used to further confirm the importance of the four terpenoid hormones. Finally, hormone content determination and qRT−PCR were performed to explore the growth and development mechanism; we found thatcis-zeatin (CZ) plays a major role in the mycelia stage, trans-zeatin (TZ) and gibberellin A4 (GA4) are important in the primordia stage, GA4 is crucial for the fruiting bodies stage, and abscisic acid (ABA) may be a marker of maturity. The IDI gene was also found to affectterpenoid hormone content by regulating the relative gene transcript levels, thereby controlling morphological changes in S. baumii. Our results revealthe growth and development mechanisms of S. baumii and may promote the breeding and utilisation of high-quality varieties.

7.
J Fungi (Basel) ; 8(6)2022 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-35736065

RESUMO

Mushrooms produce a large number of medicinal bioactive metabolites with antioxidant, anticancer, antiaging, and other biological activities. However, whether they produce flavonoids and, if so, how they synthesize them remains a matter of some debate. In the present study, we combined flavonoid-targeted metabolomics and transcriptome analysis to explore the flavonoid synthesis in the medicinal mushroom Sanghuangporus baumii. The S. baumii synthesized 81 flavonoids on a chemically defined medium. The multiple classes of flavonoids present were consistent with the biosynthetic routes in plants. However, paradoxically, most of the genes that encode enzymes involved in the flavonoid biosynthetic pathway are missing from S. baumii. Only four genes related to flavonoid synthesis were found in S. baumii, among which phenylalanine ammonia lyase gene (PAL) is a key gene regulating flavonoid synthesis, and overexpression of SbPAL increases the accumulation of flavonoids. These results suggest that the flavonoid synthesis pathway in S. baumii is different from that in known plants, and the missing genes may be replaced by genes from the same superfamilies but are only distantly related. Thus, this study provides a novel method to produce flavonoids by metabolic engineering using mushrooms.

8.
Molecules ; 27(7)2022 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-35408551

RESUMO

Inspired by the recent cocrystallization and theory of energetic materials, we theoretically investigated the intermolecular vibrational energy transfer process and the non-covalent intermolecular interactions between explosive compounds. The intermolecular interactions between 2,4,6-trinitrotoluene (TNT) and 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) and between 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX) and CL-20 were studied using calculated two-dimensional infrared (2D IR) spectra and the independent gradient model based on the Hirshfeld partition (IGMH) method, respectively. Based on the comparison of the theoretical infrared spectra and optimized geometries with experimental results, the theoretical models can effectively reproduce the experimental geometries. By analyzing cross-peaks in the 2D IR spectra of TNT/CL-20, the intermolecular vibrational energy transfer process between TNT and CL-20 was calculated, and the conclusion was made that the vibrational energy transfer process between CL-20 and TNTII (TNTIII) is relatively slower than between CL-20 and TNTI. As the vibration energy transfer is the bridge of the intermolecular interactions, the weak intermolecular interactions were visualized using the IGMH method, and the results demonstrate that the intermolecular non-covalent interactions of TNT/CL-20 include van der Waals (vdW) interactions and hydrogen bonds, while the intermolecular non-covalent interactions of HMX/CL-20 are mainly comprised of vdW interactions. Further, we determined that the intermolecular interaction can stabilize the trigger bond in TNT/CL-20 and HMX/CL-20 based on Mayer bond order density, and stronger intermolecular interactions generally indicate lower impact sensitivity of energetic materials. We believe that the results obtained in this work are important for a better understanding of the cocrystal mechanism and its application in the field of energetic materials.


Assuntos
Substâncias Explosivas , Trinitrotolueno , Transferência de Energia , Substâncias Explosivas/química , Ligação de Hidrogênio , Trinitrotolueno/química , Vibração
9.
ACS Omega ; 7(4): 3758-3767, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35128284

RESUMO

It is reported that the cis/trans conformation change of the peptide hormone oxytocin plays an important role in its receptors and activation and the cis conformation does not lead to antagonistic activity. Motivated by recent experiments and theories, the quasi-static amide-I 2D IR spectra of oxytocin are investigated using DFT/B3LYP (D3)/6-31G (d, p) in combination with the isotope labeling method under different electric fields. The theoretical amide-I IR spectra and bond length of the disulfide bond are consistent with the experimental values, which indicates that the theoretical modes are reasonable. Our theoretical results demonstrate that the oxytocin conformation is transformed from the cis conformation to the trans conformation with the change of the direction of the electric field, which is confirmed by the distance of the backbone carbonyl oxygen of Cys6 and Pro7, the Ramachandran plot of Cys6 and Pro7, the dihedral angle of Cß-S-S-Cß, and the rmsd of the oxytocin backbone. Moreover, the trans conformation as the result of the turn in the vicinity of Pro7 has a tighter secondary spatial structure than the cis conformation, including stronger hydrogen bonds, longer γ-turn geometry involving five amino acids, and a more stable disulfide bond. Our work provides new insights into the relationship between the conformation, the activation of the peptide hormone oxytocin, and the electric fields.

10.
J Thromb Thrombolysis ; 48(2): 187-194, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31177487

RESUMO

Relatively little information is known about the definitive role of phosphatidylserine (PS) in the hypercoagulability of heart failure (HF). Our objectives were to assess the levels of PS exposure on microparticles (MPs) and blood cells (BCs) in each group of HF patients and to evaluate their procoagulant activity (PCA). HF patients in each NYHA functional class II-IV (II n = 30, III n = 30, IV n = 30) and healthy controls (n = 25) were enrolled in the present study. PS exposure on MPs, BCs was analyzed with flow cytometry. MPs were classified based on their cellular origin: platelets (CD41a+), neutrophils (CD66b+), endothelial cells (CD31+CD41a-), erythrocytes (CD235a+), monocytes (CD14+), T lymphocytes (CD3+), and B lymphocytes (CD19+). PCA was evaluated by clotting time, extrinsic/intrinsic FXa and prothrombinase production assays, as well as fibrin formation assays. Inhibition assays of PCA of PS+ BCs and MPs were performed by lactadherin. There was no significant difference in MP cellular origin between healthy and HF subjects. However, the total number of PS+ MPs was significantly increased in HF patients compared with healthy controls. In addition, circulating PS+ BCs cooperated with PS+ MPs to markedly shorten coagulation time and dramatically increase FXa/thrombin generation and fibrin formation in each HF group. Moreover, blockade of exposed PS on BCs and MPs with lactadherin inhibited PCA by approximately 80%. Our results lead us to believe that exposing PS on the injured BCs and MPs played a pivotal role in the hypercoagulability state in HF patients.


Assuntos
Micropartículas Derivadas de Células/fisiologia , Células Endoteliais/fisiologia , Insuficiência Cardíaca/sangue , Fosfatidilserinas/metabolismo , Trombofilia/etiologia , Adulto , Idoso , Células Sanguíneas/patologia , Coagulação Sanguínea , Testes de Coagulação Sanguínea , Estudos de Casos e Controles , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade
11.
Int J Oncol ; 52(6): 1981-1990, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29620266

RESUMO

Multiple myeloma (MM) is characterized by an increased incidence of thromboembolic events, particularly when treated with immunomodulatory drugs (IMiDs) in combination with dexamethasone. The optimal prophylactic strategy to prevent the hypercoagulable state of patients with MM is still debated. The aim of the current study was to investigate the definitive role of phosphatidylserine (PS) in supporting procoagulant activity (PCA) in patients with MM. Patients with MM (n=20) and healthy subjects (n=15) were recruited for the present study. PS analyses were performed by flow cytometry and confocal microscopy. The PCA was evaluated by clotting time, purified coagulation complex assays and fibrin production assays. The percentage of PS+ blood cells was significantly higher in patients with MM than in healthy subjects. Additionally, the patient serum induced more PS exposure on endothelial cells (ECs) in vitro than serum from healthy subjects. Isolated blood cells from patients with MM and ECs cultured with patient serum in vitro demonstrated significantly shortened coagulation time, greatly intrinsic/extrinsic factor Xa generation and increased thrombin formation. In addition, the levels of PS+ erythrocytes, platelets, leukocytes, and ECs incubated with IMiDs and dexamethasone were higher than with IMiDs alone. The findings support the hypothesis that increased PS exposure on blood cells and ECs participates in the hypercoagulable state in patients with MM. Thus, blocking PS may be a novel therapeutic target for the prevention of thrombosis in these patients.


Assuntos
Fator Xa/metabolismo , Mieloma Múltiplo/complicações , Fosfatidilserinas/sangue , Tromboembolia Venosa/sangue , Adulto , Idoso , Coagulação Sanguínea , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/sangue , Mieloma Múltiplo/metabolismo , Células Tumorais Cultivadas , Tromboembolia Venosa/metabolismo
12.
Ying Yong Sheng Tai Xue Bao ; 25(9): 2511-20, 2014 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-25757299

RESUMO

Dendrochronological techniques including correlation functions and single-years analysis were used to study the relationship between the two kinds of Korean pine radial growth in Liangshui Natural Reserve and climatic variables, and to assess the similarities and differences between Korean pine with coarse bark (Pinus koraiensis forma pachidermis) and fine bark (Pinus koraiensis forma leptodermis) in response to climate factors, the main affecting factors and whether the response relationship could be of long-term stability. The results showed that the Korean pine with fine bark was more suitable for dendrochronological study. The radial growth of the two kinds of Korean pine was very sensitive to environmental variables and their climate responses had no significant differ- ences. From 1902 to 2009, meteorological factors in the growing season, especially in June were the primary factors affecting the radial growth of the two kinds of Korean pine in the study area. The temperature showed a significant negative correlation and the precipitation showed a significant positive correlation. The Korean pine growing in different periods had a significantly different iresponse to meteorological factors. With the rapid rise of temperature and drought after 1970, the radial growth of the two kinds of Korean pine was more sensitive to the meteorological factors than before, which was especially more sensitive to temperature in growing season and PDSI in many seasons.


Assuntos
Clima , Pinus/crescimento & desenvolvimento , China , Casca de Planta , Estações do Ano , Temperatura
13.
Opt Express ; 18(7): 7421-6, 2010 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-20389765

RESUMO

A novel prism-chamber assembly was prepared for application in optical waveguide based chemical and biological sensors, making the sensor easily and reproducibly operate. By using the prism-chamber assembly, the performance of a composite waveguide based integrated Young interferometer sensor was investigated. The temporal interference pattern detected with a single-slit photodetector heavily relies on the slit width, and regular high-contrast patterns can be obtained under the condition that the slit width is smaller than the spatial periodicity of the sensor. Increasing the temperature of water in the chamber leads to a quasi-linear variation in the phase difference with Deltaphi/DeltaT approximately -9.1 degrees/degrees C. Significant dependence of the sensor's sensitivity on the polarization state of the guided mode was also observed. The sensor is stable and reliable, capable of real-time detection of very slow bioreactions at the interface.


Assuntos
Técnicas Biossensoriais , Interferometria/métodos , Óptica e Fotônica , Algoritmos , Simulação por Computador , Desenho de Equipamento , Interferometria/instrumentação , Temperatura , Termodinâmica , Fatores de Tempo
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