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1.
J Chem Phys ; 158(13): 134711, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37031159

RESUMO

As an important phase-change material, GeTe has many high-pressure phases as well, but its phase transitions under pressure are still lack of clarity. It is challenging to identify high-pressure GeTe crystal structures owing to the phase coexistence in a wide pressure range and the reversibility of phase transitions. Hence, first-principles calculations are required to provide further information in addition to limited experimental characterizations. In this work, a new orthorhombic Cmca GeTe high-pressure phase has been predicted via the CALYPSO method as the most energetically favorable phase in the pressure range between ∼30 and ∼38.5 GPa, which would update the GeTe high-pressure phase transition sequence. The crystal structure of the Cmca phase is composed of alternate stacking puckered layers of Ge six-membered rings and Te four-membered rings along the b direction. The high density of states near the Fermi level and delocalization of electrons from the two-dimensional electron localization function indicate a strong metallic property of the Cmca phase. Electron-phonon coupling calculations indicate that the Cmca phase is superconductive below ∼4.2 K at 35 GPa. The simulated x-ray diffraction pattern of the Cmca phase implies that this phase might coexist with the Pnma-boat phase under high pressure. These results offer further understanding on the high-pressure structural evolution and physical properties in GeTe and other IV-VI semiconductors.

2.
Inorg Chem ; 61(21): 8144-8152, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35576525

RESUMO

In recent years, skutterudite filled with electronegative elements (S, Se, Cl, Br) has attracted the extensive attention of researchers. By doping electron donors (Pb, Ni, or Te, S, Se) at the Co or Sb sites, the electronegative elements can form thermodynamically stable compounds in the intrinsic pores of the skutterudite, substantially expanding the research scope of skutterudite. In this study, S0.05Co4Sb11.3Te0.6Se0.1 skutterudite was synthesized at high pressure and high temperature, with a pressure range of 2.0-3.5 GPa. The phase composition, micro-morphology, and electrical and thermal transport properties were systematically characterized. The micromorphology analysis shows that the introduction of S element and substituting Te and Se at the Sb sites inhibit the grain growth in a suitable high-pressure environment. Substantial differences are observed in the directions of the lattice stripes in the samples, and rich grain boundaries and many lattice distortions and dislocation defects occur. The carrier concentration can be optimized by filling the voids of the skutterudite with a few S atoms, and the thermoelectric properties can be optimized by scattering phonons through resonance scattering and defect scattering. The samples synthesized at a pressure of 3.0 GPa and a temperature of 900 K have a maximum power factor of 23.85 × 10-4 W m-1 K-2 and a maximum zT value of 1.30 at a test temperature of 773 K.

3.
Mamm Genome ; 32(5): 371-380, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33993322

RESUMO

Prostate cancer is not easy to metastasize because it is difficult to diagnose at an early stage, and there is no effective treatment currently. miRNA-217-5p has been reported to be a regulator in the process of prostate cancer. This study aimed to investigate how miRNA-217-5p affects the invasion and migration of prostate cancer. Luciferase assay was used to clarify whether the target gene Clusterin (CLU) was interacted directly with miR-217-5p. miR-217-5p and CLU were knocked down by transfecting respective siRNA into DU145 cells. The expression level of epithelial-mesenchymal transition (EMT)-related proteins was detected by Western blotting. Invasion and migration of DU145 cell were examined by wound healing assay. The results showed that miR-217-5p directly interacted with its target gene CLU, and the transfection of si-CLU and si-miR-217-5p had similar ability to regulate the expression level of EMT-related proteins, which in turn affected the migration and invasion of prostate cancer cell line DU145. In addition, miR-217-5p inhibited the expression of EMT-related proteins by regulating the expression of the target gene CLU, and further inhibited the invasion and migration of prostate cancer cells. Our findings provide a theoretical target basis for the treatment of prostate cancer.


Assuntos
Clusterina/metabolismo , MicroRNAs/genética , Invasividade Neoplásica/genética , Metástase Neoplásica/genética , Neoplasias da Próstata/patologia , Transição Epitelial-Mesenquimal/genética , Humanos , Masculino
4.
Appl Microbiol Biotechnol ; 104(4): 1545-1553, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31897521

RESUMO

Increasing attention has recently been focused on complex symbiotic associations, for instance coral and its symbionts. Sea cucumber, harboring diverse fungi, has also attracted more and more attention for their functional diversity. Here, secondary metabolites produced by Chaetomium globosum associated with sea cucumber, Apostichopus japonicus, were investigated using gene mining with third-generation sequencing technology (PacBio SMRT). Nine compounds, including one new compound cytoglobosin X (1), were isolated from cultures of Chaetomium globosum. Compound 1 was identified based on NMR data, HRESIMS, and ECD, and the absolute configurations were identified as 3S, 4R, 7S, 8R, 9R, 16S, 19S, 20S, and 23S. In an antimicrobial assay, compound 4 showed moderate activity against Staphylococcus aureus and methicillin-resistant Staphylococcus aureus with MICs of 47.3 and 94.6 µM, respectively. Our results suggest that the microbiomes associated with sea cucumber could be an important resource for biodiversity and structural novelty, and the bioactive compounds may protect the host from pathogen microbial.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Benzopiranos/farmacologia , Chaetomium/química , Alcaloides Indólicos/farmacologia , Pigmentos Biológicos/farmacologia , Stichopus/microbiologia , Animais , Antibacterianos/isolamento & purificação , Benzopiranos/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Alcaloides Indólicos/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Pigmentos Biológicos/isolamento & purificação , Metabolismo Secundário , Staphylococcus aureus/efeitos dos fármacos , Simbiose
6.
Inorg Chem ; 57(11): 6762-6766, 2018 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-29792420

RESUMO

It has been discussed for a long time that synthetic pressure can effectively optimize thermoelectric properties. The beneficial effect of synthesis pressures on thermoelectric properties has been discussed for a long time. In this paper, it is theoretically and experimentally demonstrated that appropriate synthesis pressures can increase the figure of merit (ZT) through optimizing thermal transport and electronic transport properties. Indium and barium atoms double-filled CoSb3 samples were prepared use high-pressure and high-temperature technique for half an hour. X-ray diffraction and some structure analysis were used to reveal the relationship between microstructures and thermoelectric properties. In0.15Ba0.35Co4Sb12 samples were synthesized by different pressures; sample synthesized by 3 GPa has the best electrical transport properties, and sample synthesized by 2.5 GPa has the lowest thermal conductivity. The maximum ZT value of sample synthesized by 3.0 GPa reached 1.18.

7.
Inorg Chem ; 57(6): 3323-3328, 2018 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-29494140

RESUMO

The thermoelectric (TE) properties of n-type polycrystalline Yb0.5Ba7.5Ga16Ge30 bulks can be optimized by high-pressure and high-temperature (HPHT) sintering. After HPHT sintering, abundant nanograins are randomly distributed in the sample. Grains are refined by HPHT, with the grains being smaller with higher pressure. In comparison with the arc-melted sample, the samples obtained by quenching under high pressure possess a great number of nanograins and lattice structural disorders. Lower thermal conductivity is benefited by our deliberately engineered microstructures via HPHT, and the minimum thermal conductivity is 0.86 W m-1 K-1 at 773 K. The thermal conductivity and electrical properties are optimized simultaneously by raising the reactive sintering pressure. In comparison with the arc-melted sample (0.56), a maximum zT value of 1.13 at 773 K is obtained for the Yb0.5Ba7.5Ga16Ge30 sample fabricated at 5 GPa. This demonstrates that HPHT provides an effective strategy to improve TE performance through simultaneously enhancing electrical and thermal transport properties and should be applicable to other thermoelectric materials.

8.
IUBMB Life ; 69(1): 16-21, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27862841

RESUMO

Epithelial to mesenchymal transition (EMT) is an important prerequisite for metastasis to secondary organs. Interleukin-like EMT inducer (ILEI) protein has been shown to translationally upregulated during EMT and metastatic progression as a consequence of aberrant TGF-ß signaling. Our initial evaluation of FAM3C (encoding ILEI) and ILEI expression in normal prostate (PCS-440-010) and prostate cancer cell lines (DU145, LNCaP, and PC3) revealed detectable protein expression in only LNCaP cell line even though all cell lines tested had comparable FAM3C expression. Given that PC3 and DU145 cell lines did not have detectable ILEI expression hinted at additional level of regulation of ILEI expression. Treatment with MG-132 resulted in robust detection of ILEI in the PCS-440-010, PC3 and DU145 cell lines, suggesting that at least in these cell lines, ILEI is actively degraded by the proteasome. Mass spectrometric analysis of FLAG immunoprecipitates of untreated and MG-132 treated FLAG-ILEI transfected cells indicated that UBE4A and UBE3C ubiquitin ligases were interacting with ILEI. Ectopic overexpression of UBE4A, but not UBE3C, resulted in destabilization of ILEI in LNCaP cells, whereas RNAi-mediated silencing of UBE4A in PCS-440-010, PC3 and DU145 cell lines resulted in robust accumulation of ILEI, indicating UBE4A as the cognate ubiquitin ligase for ILEI. Co-immunoprecipitation experiments established direct interaction of endogenous ILEI and UBE4A. Furthermore, co-immunoprecipitation of FLAG-tagged ILEI in cells co-transfected with either HA-UBE4A or HA-UBE3C revealed robust polyubiquitinated smear of ILEI in cells transfected with UBE4A, but not UBE3C, thus confirming UBE4A as the ubiquitin ligase for ILEI degradation. Ectopic overexpression of UBE4A, but not UBE3C, in cells was downregulated in vitro migration and invasion in these cells. Cumulatively, our data reveals a novel post-translational regulatory mechanism of regulating ILEI1 expression, a protein required for metastatic progression in prostate cancer cells. © 2016 IUBMB Life, 69(1):16-21, 2017.


Assuntos
Citocinas/genética , Proteínas de Neoplasias/genética , Neoplasias da Próstata/genética , Ubiquitina-Proteína Ligases/biossíntese , Linhagem Celular Tumoral , Movimento Celular/genética , Citocinas/biossíntese , Citocinas/metabolismo , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Invasividade Neoplásica/genética , Metástase Neoplásica , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/metabolismo , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Ubiquitina-Proteína Ligases/genética
9.
Inorg Chem ; 56(18): 11275-11281, 2017 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-28853562

RESUMO

We developed suitable high-pressure and high-temperature (HPHT) conditions for improvement of the thermoelectric properties of nonstoichiometric TiO1.80. X-ray diffraction, scanning transmission microscopy, transmission electron microscopy, and ultraviolet spectral measurements demonstrate that the crystal structures and microstructures are strongly modulated by our HPHT. The electrical properties and thermal conductivity are improved simultaneously by raising the reactive sintering pressure. The band gap was narrowed, contributing to the increase of the electrical properties with the pressure. In addition, relatively low thermal conductivities were obtained here as a result of a full spectrum of phonon scattering, benefiting from our deliberately engineered microstructures via HPHT. As a consequence, a high dimensionless figure of merit (zT) of 0.36 was obtained at 700 °C in the sample fabricated at 5 GPa. As far as we know, this is higher than all of the results of nonstoichiometric titanium oxide by other means and an enhancement of 57% of the best ever result. HPHT offers us a promising alternative for optimization of the thermoelectric properties, and it is worthwhile to popularize it.

10.
Lipids Health Dis ; 16(1): 59, 2017 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-28330470

RESUMO

BACKGROUND: Present study aimed to better understand the potential apoptotic pathways that involved in docosahexaenoic acid (DHA)-induced apoptosis of prostate cancer cells. METHODS: Human prostate cancer DU145 cells were treated with different concentrations of fish oil, omega-3 PUFA (DHA, and Eicosapentaenoic acid, EPA), or omega-6 PUFA (Arachidonic acid, AA). Cell viability and apoptosis were evaluated by MTT assay and Hoechst staining. Pathway-focused gene expression profiling of DU145 cells was analyzed with the RT2 Profile PCR Array System. The results were verified by real time quantitative polymerase chain reaction (RT-qPCR). RESULTS: AA exposure showed no obvious effect on viability of DU145 cells. However, exposure with fish oil, EPA, or DHA for 24 h significantly affected cell viability. The growth inhibition of DHA was more pronounced than that of EPA and showed a time-dependent increase. DHA exposure caused typical apoptotic characteristics. Ten genes were more expressed, while 5 genes were less expressed following DHA exposure. RT-qPCR confirmed the time dependent effect of DHA on the expression of these differentially expressed genes. KEGG pathway analysis showed that DHA may induce the apoptosis of cancer cells preferentially through mediating P53, MAPK, TNF, PI3K/AKT, and NF-κB signaling pathways. CONCLUSION: Our study demonstrated the beneficial action of DHA on human prostate carcinoma cell line DU145. The pro-apoptotic effect of DHA on DU145 cells may involve mediation various pathways, especially P53, MAPK, TNF, PI3K/AKT, and NF-κB signaling pathways. Molecular mechanisms of DHA on apoptosis of cancer cells still need to be further clarified.


Assuntos
Apoptose/efeitos dos fármacos , Ácidos Docosa-Hexaenoicos/farmacologia , Ácido Eicosapentaenoico/farmacologia , Regulação Neoplásica da Expressão Gênica , Próstata/efeitos dos fármacos , Ácido Araquidônico/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Perfilação da Expressão Gênica , Humanos , Masculino , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Próstata/metabolismo , Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-26113008

RESUMO

BACKGROUND: The aim of our study was to investigate the clinical role of aldehyde dehydrogenase 1 (ALDH1) and leucine-rich repeat-containing G-protein-coupled receptor 5 (Lgr5) expressions in epithelial ovarian cancer (EOC) and their prognostic significance. METHODS: One hundred primary EOC samples were obtained for immunohistochemical analysis of ALDH1 and Lgr5 expressions. Correlation analysis was performed between ALDH1 or Lgr5 and clinical factors. RESULTS: High expression of ALDH1 and Lgr5 was identified in 71 and 55 cases of EOC tissues, respectively. The ALDH1 and Lgr5 expressions in EOC tissues were significantly higher as compared to the normal ovaries and benign ovarian tumors. High expression of ALDH1 and Lgr5 was strongly correlated with advanced International Federation of Gynecology and Obstetrics (FIGO) stages, higher tumor grades, and poor overall survival of the patients. CONCLUSIONS: Lgr5 and ALDH1 were highly expressed in EOC tissues, and correlated with different FIGO operation-pathological stages and tumor grades, clinical outcome, and with each other. The combined use of ALDH1 and Lgr5 might be useful for the diagnosis and prognosis prediction of EOC patients. © 2015 S. Karger AG, Basel.

12.
IUBMB Life ; 66(12): 847-53, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25631296

RESUMO

Recent reports have indicated that not only the primary glandular tissue but also the surrounding stromal tissue plays an active role in the progression of carcinoma. Such is true for cancer tissues arising in the prostate. However, the precise role of stromal tissue in benign prostatic hyperplasia (BPH) and prostate adenocarcinoma is not well described. We undertook this current investigation to examine the changes in orientation of the extracellular matrix and correlate with prostatic cancer progression. We used a novel form of image analysis called gray level entropy matrix (GLEM) texture analysis to evaluate morphometric changes in stromal tissues. We used normal prostatic tissue obtained from cadaveric specimen and compared with BPH, prostatic intraepithelium neoplastic, hormone responsive prostatic adenocarcinoma and castration-resistant prostatic adenocarcinoma tissues. GLEM showed higher entropy in disease-resistant prostatic tissues, compared with benign forms of all spectra of pathologically diagnosed prostatic tissues (P < 0.05, ANOVA, between groups). Higher entropy is reflective of the disorganized morphological organization of the stroma, possibly reflecting the reactive matrix. In contrast, ELISA revealed that although individually correlated with the progressive stages of benign and carcinomatous prostatic tissues and trend correlation between groups, intergroup comparisons failed to arrive at statistical significance of comparisons between markers of neovasculogenesis, vascular endothelial growth factor, epithelial-mesenchymal transition (beta1-integrin, E-cadherin, MMP3) and osteogenic metastasis (RANKL and osteoprotegerin). The results of our study demonstrate the potential of GLEM entropy of gray level pixel in providing quasiquantitative estimate of a reactive stroma in advance stages of prostatic adenocarcinoma and thus can be routinely used in clinical decision making.


Assuntos
Biomarcadores Tumorais/análise , Entropia , Próstata/patologia , Hiperplasia Prostática/patologia , Neoplasia Prostática Intraepitelial/secundário , Neoplasias da Próstata/patologia , Células Estromais/patologia , Idoso , Idoso de 80 Anos ou mais , Cadáver , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Estudos de Viabilidade , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Próstata/metabolismo , Hiperplasia Prostática/metabolismo , Neoplasia Prostática Intraepitelial/metabolismo , Neoplasias da Próstata/metabolismo , Células Estromais/metabolismo , Células Tumorais Cultivadas
13.
ScientificWorldJournal ; 2014: 620610, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25089295

RESUMO

The interaction of wind and water in semiarid and arid areas usually leads to low-frequency flash flood events in desert rivers, which have adverse effects on river systems and ecology. In arid zones, many aeolian dune-fields terminate in stream channels and deliver aeolian sand to the channels. Although aeolian processes are common to many desert rivers, whether the aeolian processes contribute to fluvial sediment loss is still unknown. Here, we identified the aeolian-fluvial cycling process responsible for the high rate of suspended sediment transport in the Sudalaer desert stream in the Ordos plateau of China. On the basis of element geochemistry data analysis, we found that aeolian sand was similar to suspended sediment in element composition, which suggests that aeolian sand contributes to suspended sediment in flash floods. Scatter plots of some elements further confirm that aeolian sand is the major source of the suspended sediment. Factor analysis and the relation between some elements and suspended sediment concentration prove that the greater the aeolian process, the higher the suspended sediment concentration and the greater the contribution of aeolian sand to suspended sediment yield. We conclude that aeolian sand is the greatest contributor to flash floods in the Sudalaer desert stream.


Assuntos
Inundações , Sedimentos Geológicos/análise , China , Monitoramento Ambiental , Rios
14.
Anticancer Agents Med Chem ; 23(14): 1626-1633, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37638593

RESUMO

Background/Introduction: Prostate cancer ranks as the second leading cause of cancer death. No effective pharmacological agent is available for prostate cancer treatment. Berbamine is an alkaloid extracted from the Chinese herb berberis, which exerts an effect on inhibiting cancer cell proliferation. OBJECTIVE: This study aimed to explore the mechanism of berbamine in inhibiting prostate cancer. METHODS: Prostate cancer cell lines PC-3 and DU145 cells were used to evaluate the effects of berbamine. Cell viability was determined using cell-counting kit 8. The intracellular reactive oxygen species (ROS) levels were measured using a ROS assay kit. Cell apoptosis rate was examined using flow cytometry. The protein levels associated with cell proliferation, NF-κB pathway, and apoptosis were determined using western blot. RESULTS: It was found that berbamine induced cell cycle arrest in the S phase and inhibited prostate cancer cell growth and proliferation. Berbamine inhibited prostate cancer cells by inhibiting the activation of the NF-κB pathway in vitro. Berbamine increased ROS as an upstream molecule that inhibited the NF-κB pathway. CONCLUSION: Our results demonstrated that berbamine can effectively reduce the proliferation of prostate cancer cells. The ROS/NF-κB axis plays a crucial role in berbamine-mediated anti-prostate cancer cell proliferation.


Assuntos
Hiperplasia Prostática , Neoplasias da Próstata , Humanos , Masculino , NF-kappa B , Espécies Reativas de Oxigênio , Neoplasias da Próstata/tratamento farmacológico , Próstata
15.
Am J Cancer Res ; 13(9): 4115-4124, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37818083

RESUMO

In this study, we aim to investigate the role and mechanism of T-box transcription factor 3 (TBX3) in cervical cancer. The mRNA and protein expression of TBX3, inhibitor of DNA binding 1 (ID1), and epithelial mesenchymal transition (EMT) markers (E-Cadherin, N-Cadherin, and vimentin) were measured using qRT-PCR and Western blot. shTBX3 and shID1 were transfected into SiHa cells to knockdown TBX3 and ID1. The metastasis and invasion abilities of cervical cancer cells were determined using a wound healing assay and an invasive assay. The shTBX3- and shID1-transfected SiHa cells were injected into nude mice using a xenograft tumor growth model. We found that TBX3 and ID1 were highly expressed in cervical cancer cells. Importantly, silencing TBX3 and ID1 significantly reduced the migration and metastasis of cervical cancer cells. In addition, silencing TBX3 and ID1 significantly inhibited the EMT, evidenced by the increased E-cadherin, and decreased N-cadherin and vimentin. The size and weight of the xenograft tumor were significantly reduced by shTBX3 and shID1. We demonstrate that TBX3 or ID1 knockdown can effectively inhibit cervical cancer cells migration and invasion. These findings indicate that TBX3 and ID1 can act as potential therapeutic targets for the prevention and treatment of cervical cancer.

16.
Bioresour Technol ; 390: 129846, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37820970

RESUMO

Tar problem seriously hinders the development of biomass gasification. The tar formation of biomass is greatly influenced by cellulose. In this work, PY-GC/MS was employed for providing a precise insight into the formation of primary and secondary products, and a tar contribution index was introduced to evaluate the potential of tar formation from different origins. Combined with statistical analysis and corroboration by DFT analysis, key intermediates for tar formation are recognized, and corresponding influence is confirmed. A new framework from cellulose to tar was built. The secondary reaction acts a more important role for tar formation. The aromatic precursors and high-activity small-molecular gases are two key compounds responding to tar formation, and the existence of high-activity small-molecular gases could significantly reduce the energy barrier during tar formation. For furans, the energy barrier can be reduced from 100.2 kcal/mol to 74.2 kcal/mol in the presence of ethylene.


Assuntos
Celulose , Gases , Biomassa
17.
BMC Biotechnol ; 12: 55, 2012 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-22916830

RESUMO

BACKGROUND: The ketoisovalerate reductase (EC 1.2.7.7 ) is required for the formation of beauvericin via the nonribosomal peptide synthetase biosynthetic pathway. It catalyzes the NADPH-specific reduction of ketoisovaleric acid to hydroxyisovalerate. However, little is known about the bioinformatics' data about the 2-Kiv reductase in Fusarium. To date, heterologous production of the gene KivRFp from Fusarium has not been achieved. RESULTS: The KivRFp gene was subcloned and expressed in Escherichia coli BL21 using the pET expression system. The gene KivRFp contained a 1,359 bp open reading frame (ORF) encoding a polypeptide of 452 amino acids with a molecular mass of 52 kDa. Sequence analysis indicated that it showed 61% and 52% amino acid identities to ketoisovalerate reductase from Beauveria bassiana ATCC 7159 (ACI30654) and Metarhizium acridum CQMa 102 (EFY89891), respectively; and several conserved regions were identified, including the putative nucleotide-binding signature site, GXGXXG, a catalytic triad (Glu405, Asn184, and Lys285). The KivRFp exhibited the highest activity at 35°C and pH 7.5 respectively, by reduction of ketoisovalerate. It also exhibited the high level of stability over wide temperature and pH spectra and in the presence of metal ions or detergents. CONCLUSIONS: A new ketoisovalerate reductase KivRFp was identified and characterized from the depsipeptide-producing fungus F. proliferatum. KivRFp has been shown to have useful properties, such as moderate thermal stability and broad pH optima, and may serve as the starting points for future protein engineering and directed evolution, towards the goal of developing efficient enzyme for downstream biotechnological applications.


Assuntos
Oxirredutases do Álcool/química , Oxirredutases do Álcool/genética , Clonagem Molecular , Depsipeptídeos/biossíntese , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Fusarium/enzimologia , Oxirredutases do Álcool/metabolismo , Sequência de Aminoácidos , Estabilidade Enzimática , Proteínas Fúngicas/metabolismo , Fusarium/química , Fusarium/classificação , Fusarium/genética , Fusarium/metabolismo , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência
18.
Front Pharmacol ; 13: 894812, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35645804

RESUMO

Endotoxins and other harmful substances may cause an increase in permeability in endothelial cells (ECs) monolayers, as well as ECs shrinkage and death to induce lung damage. Lipopolysaccharide (LPS) can impair endothelial progenitor cells (EPCs) functions, including proliferation, migration, and tube formation. EPCs can migrate to the damaged area, differentiate into ECs, and participate in vascular repair, which improves pulmonary capillary endothelial dysfunction and maintains the integrity of the endothelial barrier. Hydrogen (H2) contributes to the repairment of lung injury and the damage of ECs. We therefore speculate that H2 protects the EPCs against LPS-induced damage, and it's mechanism will be explored. The bone marrow-derived EPCs from ICR Mice were treated with LPS to establish a damaged model. Then EPCs were incubated with H2, and treated with PI3K inhibitor LY294002 and endothelial nitric oxide synthase (eNOS) inhibitor L-NAME. MTT assay, transwell assay and tube formation assay were used to detect the proliferation, migration and angiogenesis of EPCs. The expression levels of target proteins were detected by Western blot. Results found that H2 repaired EPCs proliferation, migration and tube formation functions damaged by LPS. LY294002 and L-NAME significantly inhibited the repaired effect of H2 on LPS-induced dysfunctions of EPCs. H2 also restored levels of phosphor-AKT (p-AKT), eNOS and phosphor-eNOS (p-eNOS) suppressed by LPS. LY294002 significantly inhibited the increase of p-AKT and eNOS and p-eNOS expression exposed by H2. L-NAME significantly inhibited the increase of eNOS and p-eNOS expression induced by H2. H2 repairs the dysfunctions of EPCs induced by LPS, which is mediated by PI3K/AKT/eNOS signaling pathway.

19.
Environ Monit Assess ; 173(1-4): 969-83, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20354782

RESUMO

The Yellow River flows through an extensive, aeolian desert area and extends from Xiaheyan, Ningxia Province, to Toudaoguai, Inner Mongolia Province, with a total length of 1,000 km. Due to the construction and operation of large reservoirs in the upstream of the Yellow River, most water and sediment from upstream were stored in these reservoirs, which leads to the declining flow in the desert channel that has no capability to scour large amount of input of desert sands from the desert regions. By analyzing and comparing the spatial distribution of weight percent of mineral compositions between sediment sources and riverbed sediment of the main tributaries and the desert channel of the Yellow River, we concluded that the coarse sediment deposited in the desert channel of the Yellow River were mostly controlled by the local sediment sources. The analyzed results of the Quartz-Feldspar-Mica (QFM) triangular diagram and the R-factor models of the coarse sediment in the Gansu reach and the desert channel of the Yellow River further confirm that the Ningxia Hedong desert and the Inner Mongolian Wulanbuhe and Kubuqi deserts are the main provenances of the coarse sediment in the desert channel of the Yellow River. Due to the higher fluidity of the fine sediment, they are mainly contributed by the local sediment sources and the tributaries that originated from the loess area of the upper reach of the Yellow River.


Assuntos
Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Rios , China , Análise Fatorial
20.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(1): 181-187, 2021 Feb.
Artigo em Zh | MEDLINE | ID: mdl-33554816

RESUMO

OBJECTIVE: To deeply understand the clinical manifestation, laboratory examination characteristics, diagnosis and treatment of an eight p11 myeloproliferative syndrome (EMS) with rare phenotypes. METHODS: The clinical and laboratory characteristics and the process of allogeneic hematopoietic stem cell transplantation (allo-HSCT) were summarized in 1 rare EMS case involving T/B/myeloid cells. Meanwhile, 2 similar cases in the previous literature were also discussed. RESULTS: The bone marrow examination indicated that the patient with B-cell acute lymphocytic leukemia. The lymph node biopsy showed that the patient was T lymphoblastic/myeloid lymphoma. The 8p11 abnormality was found by the examination of bone marrow chromosomes. The RT-PCR examination showed that the BCR-ABL fused gene was negtive. The FGFR1 breakage was found by using the FISH with FGFR1 probe in lymph node. The Mutation of FMNL3, NBPF1 and RUNX1 genes was found by using the whole exome sequencing. The patient received allo-HSCT under CR2. By the follow-up till to September 2019, the patient survived without the above-mentioned disease. CONCLUSION: EMS manifest as neoplasms involving T-lineage, B-lineage, and myeloid-lineage simultaneously is extremely rare. Although the FGFR1 gene-targeted therapy can be conducted, allo-HSCT should be actively considered.


Assuntos
Neoplasias Hematológicas , Transtornos Mieloproliferativos , Medula Óssea , Cromossomos Humanos Par 8 , Forminas , Humanos , Transtornos Mieloproliferativos/genética , Fenótipo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Translocação Genética
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