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1.
Phys Chem Chem Phys ; 25(23): 15929-15940, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37260414

RESUMEN

This paper investigated the defect generation mechanism of two self-made ytterbium-doped fibers (a Yb-doped fiber and a Yb/Ce-doped fiber) under proton irradiation and the influence of Ce-doping on proton radiation defects. The macroscopic damage of different optical fibers caused by proton irradiation energy and irradiation doses was further studied. Fluorescence spectroscopy, EPR electron paramagnetic resonance and SEM experiments were used to characterize the micro defects and macro damage of the fibers. The following conclusions are drawn: the damage on the surface of optical fibers increases continuously with the increase of irradiation dose, and does not change significantly with the increase of proton energy. The main defect in the irradiated fibers is proved to be the Al-OHC defect which leads to energy loss in the visible light region and a photon darkening effect. After Ce doping, the change trend of the amount of Al-OHC defect is greatly suppressed, while it shows little effect on the oxygen defect (intrinsic), and basically does not change this trend. On the other hand, Ce doping can also effectively reduce the generation of Si-E' defects in the irradiated fibers according to the EPR electron paramagnetic resonance experiment. In conclusion, due to the presence of two valence states of Ce ions, Ce doping prominently improves the performance of high-power Yb-doped fibers under proton irradiation.

2.
Appl Microbiol Biotechnol ; 107(10): 3191-3204, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37058231

RESUMEN

Lignocellulosic biomass has emerged as a promising environmental resource. Enzyme catalysis, as one of the most environmentally friendly and efficient tools among various treatments, is used for the conversion of biomass into chemicals and fuels. Cellulase is a complex enzyme composed of ß-glucosidase (BGL), endo-ß-1,4-glucanase (EG), and exo-ß-1,4-glucanase (CBH), which synergistically hydrolyzes cellulose into monosaccharides. BGL, which further deconstructs cellobiose and short-chain cellooligosaccharides obtained by EG and CBH catalysis into glucose, is the most sensitive component of the synergistic enzyme system constituted by the three enzymes and is highly susceptible to inactivation by external conditions, becoming the rate-limiting component in biomass conversion. This paper firstly introduces the source and catalytic mechanism of BGL used in the process of biomass resource utilization. The focus is on the review of various factors affecting BGL activity during hydrolysis, including competitive adsorption of lignin, gas-liquid interface inactivation, thermal inactivation, and solvent effect. And the methods to improve BGL inactivation are proposed from two aspects-substrate initiation and enzyme initiation. In particular, the screening, modification, and alteration of the enzyme molecules themselves are discussed with emphasis. This review can provide novel ideas for studies of BGL inactivation mechanism, containment of inactivation, and activity enhancement. KEY POINTS: • Factors affecting ß-glucosidase inactivation are described. • Process intensification is presented in terms of substrate and enzyme. • Solvent selection, protein engineering, and immobilization remain topics of interest.


Asunto(s)
Celulasa , beta-Glucosidasa , beta-Glucosidasa/metabolismo , Biomasa , Celulosa/metabolismo , Lignina/metabolismo , Hidrólisis , Solventes , Celulasa/metabolismo
3.
Biotechnol Lett ; 45(11-12): 1529-1539, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37831286

RESUMEN

PURPOSE: Erythritol is a valuable compound as sweetener and chemical material however cannot be fermented from the abundant substrate xylose. METHODS: The strain Trichosporonoides oedocephalis ATCC 16958 was employed to produce polyols including xylitol and erythritol by metabolic engineering approaches. RESULTS: The introduction of a substrate-specific ribose-5-phosphate isomerase endowed T. oedocephalis with xylose-assimilation activity to produce xylitol, and eliminated glycerol production simultaneously. A more value-added product, erythritol was produced by further introducing a homologous xylulose kinase. The carbon flux was redirected from xylitol to erythritol by adding high osmotic pressure. The production of erythritol was improved to 46.5 g/L in flasks by fermentation adjustment, and the process was scaled up in a 5-L fermentor, with a 40 g/L erythritol production after 120 h, and a time-space yield of 0.56 g/L/h. CONCLUSION: This study demonstrated the potential of T. oedocephalis in the synthesis of multiple useful products from xylose.


Asunto(s)
Eritritol , Xilitol , Xilosa/metabolismo , Fermentación , Redes y Vías Metabólicas
4.
Lasers Med Sci ; 38(1): 223, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37758965

RESUMEN

The choice between radiotherapy (RT) and CO2 laser surgery (CO2-LS) for early glottic cancer remains controversial. We systematically examined electronic databases in order to identify prospective trials comparing patients who had undergone CO2-LS or RT to treat early glottic cancer. Eleven studies involving 1053 patients were included. In the selected literature, the parameter setting of CO2 laser equipment can be summarized as wavelength 10.6 µm, superpulsed mode, continuous setting, power tailored on target structures (1-3 W for subtle resections and 4-15 W for cutting a larger tumor), and approximately 2080-3900 W/cm2 of laser energy. Using RevMan 5.3, we estimated pooled odds ratios (ORs) for dichotomous variables and pooled mean differences (MDs) for continuous variables, along with associated 95% confidence intervals (CIs). The heterogeneity in the treatment variables was measured using Higgins' inconsistency test and expressed as I2 values. The continuous variables were then depicted as histograms developed using PlotDigitizer 2.6.8. Compared to patients treated with CO2-LS, those treated with RT had better jitter (MD 1.27%, 95% CI 1.21 ~ 1.32, P < 0.001), and high scores on the "Grade (MD 6.54, 95% CI 5.31 ~ 7.76, P < 0.001), Breathiness (MD 9.08, 95% CI 4.02 ~ 14.13, P < 0.001), Asthenia (MD 2.13, 95% CI 0.29 ~ 3.98, P = 0.02), and Strain (MD 3.32, 95% CI 0.57 ~ 6.07, P = 0.02)" scale. Patients treated with CO2-LS had worse local control rates (OR 3.14, 95% CI 1.52 ~ 6.48, P = 0.002) while lower incidence of second primary tumor (OR 0.30, 95% CI 0.15 ~ 0.61, P < 0.001). It is hoped that retrospective analysis can provide suggestions for early glottis patients to choose personalized treatment.


Asunto(s)
Neoplasias Laríngeas , Terapia por Láser , Neoplasias de la Lengua , Humanos , Dióxido de Carbono , Resultado del Tratamiento , Estudios Retrospectivos , Microcirugia , Neoplasias Laríngeas/radioterapia , Neoplasias Laríngeas/cirugía , Neoplasias Laríngeas/patología , Estudios Prospectivos , Terapia por Láser/efectos adversos , Glotis/cirugía , Glotis/patología , Neoplasias de la Lengua/patología
5.
J Sci Food Agric ; 103(4): 1974-1980, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36448581

RESUMEN

BACKGROUND: The fermentation valorization of two main lignocellulosic monosaccharides, glucose and xylose, is extensively developed; however, it is restricted by limited yield and process complexity. An in vitro enzymatic cascade reaction can be an alternative approach. RESULTS: In this study, a three-stage, five-enzyme cascade was developed to convert pretreated biomass to valuable chemicals. First, a ribose-5-phosphate isomerase B mutant isomerized xylose to d-xylulose with high substrate specificity, and a d-arabinose dehydrogenase continued to reduce d-xylulose to d-arabitol. Simultaneously, glucose was utilized for the coenzyme regeneration catalyzed by a glucose dehydrogenase, generating useful gluconic acid and achieving 73% of total conversion rate after 36 h. Then, six kinds of pretreated biomass lignocellulose were hydrolyzed by cellulase and hemicellulase, and corn cob was identified as the initial substrate for providing the highest monosaccharide content. A 65% conversion rate of the lignocellulosic xylose was obtained after 24 h. CONCLUSIONS: This study presents a proof of concept to convert main lignocellulosic monosaccharides systematically by an enzymatic cascade at stoichiometric ratio. © 2022 Society of Chemical Industry.


Asunto(s)
Monosacáridos , Xilosa , Xilulosa , Lignina/metabolismo , Glucosa , Fermentación
6.
Zhongguo Zhong Yao Za Zhi ; 48(23): 6434-6441, 2023 Dec.
Artículo en Zh | MEDLINE | ID: mdl-38212001

RESUMEN

This study aimed to investigate the effect and underlying mechanism of Poria cocos polysaccharides(PCP) on myocardial cell apoptosis in the rat model of myocardial ischemia-reperfusion injury(MI/RI). Male SPF-grade SD rats were randomly divided into a sham group(saline), a model group(saline), low-and high-dose PCP groups(100 and 200 mg·kg~(-1)), and a fasudil group(10 mg·kg~(-1)), with 16 rats in each group. Except for the sham group, the other four groups underwent left anterior descending coronary artery ligation for 30 min followed by reperfusion for 2 h to establish the MI/RI model. The myocardial infarct area was assessed by TTC staining. Histological changes were observed through HE staining. Myocardial cell apoptosis was evaluated using TUNEL staining. Serum lactate dehydrogenase(LDH), creatine kinase MB(CK-MB), interleukin-1ß(IL-1ß) and IL-18 levels, myocardial superoxide dismutase(SOD) activity and malondialdehyde(MDA) levels were detected by ELISA. Protein expression of B-cell lymphoma 2(Bcl-2), Bcl-2 associated X protein(Bax), cleaved caspase-3, Ras homolog gene A(RhoA), myosin phosphatase target subunit 1(MYPT-1), phosphorylated MYPT-1(p-MYPT-1), and Rho-associated coiled-coil forming kinase 1(ROCK 1) were measured by Western blot. Pathological staining of myocardial tissue revealed that in the model group, there was focal necrosis of myocardial tissue, myocardial cell swelling, unclear boundaries, and neutrophil infiltration. These pathological changes were alleviated in the low-and high-dose PCP groups and the fasudil group. Compared with the model group, the low-and high-dose PCP groups and the fasudil group showed significantly reduced myocardial infarct area and myocardial cell apoptosis rate. Compared with the sham group, the model group exhibited elevated serum LDH, CK-MB, IL-1ß and IL-18 levels, increased MDA levels, relative protein expression of Bax, cleaved caspase-3, RhoA, ROCK1 and p-MYPT-1, and decreased myocardial SOD levels and Bcl-2 protein expression. Compared with the model group, the PCP groups and the fasudil group showed lowered serum LDH, CK-MB, IL-1ß and IL-18 levels, decreased MDA levels, relative protein expression of Bax, cleaved caspase-3, RhoA, ROCK1 and p-MYPT-1, and increased myocardial SOD levels and Bcl-2 protein expression. PCP exhibited a certain preventive effect on myocardial tissue pathological damage and myocardial cell apoptosis in MI/RI rats, possibly related to the inhibition of the Rho-ROCK signaling pathway activation, thereby reducing oxidative stress and inflammatory responses.


Asunto(s)
1-(5-Isoquinolinesulfonil)-2-Metilpiperazina/análogos & derivados , Infarto del Miocardio , Daño por Reperfusión Miocárdica , Wolfiporia , Ratas , Masculino , Animales , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Proteína X Asociada a bcl-2/metabolismo , Ratas Sprague-Dawley , Caspasa 3/metabolismo , Interleucina-18 , Transducción de Señal , Infarto del Miocardio/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Forma MB de la Creatina-Quinasa , Apoptosis , Polisacáridos/farmacología , Superóxido Dismutasa/metabolismo
7.
BMC Neurosci ; 23(1): 56, 2022 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-36171542

RESUMEN

BACKGROUND: Dysregulation of long noncoding RNA (lncRNA) expression is related to aging and age-associated neurodegenerative diseases, and the lncRNA expression profile in the aging hippocampus is not well characterized. In the present investigation, the changed mRNAs and lncRNAs were confirmed via deep RNA sequencing. GO and KEGG pathway analyses were conducted to investigate the principal roles of the clearly dysregulated mRNAs and lncRNAs. Subsequently, through the prediction of miRNAs via which mRNAs and lncRNAs bind together, a competitive endogenous RNA network was constructed. RESULTS: A total of 447 lncRNAs and 182 mRNAs were upregulated, and 385 lncRNAs and 144 mRNAs were downregulated. Real-time reverse transcription-polymerase chain reaction validated the reliability of mRNA and lncRNA sequencing. KEGG pathway and GO analyses revealed that differentially expressed (DE) mRNAs were associated with cell adhesion molecules (CAMs), the p53 signaling pathway (SP), phagosomes, PPAR SP and ECM-receptor interactions. KEGG pathway and GO analyses showed that the target genes of the DE lncRNAs were related to cellular senescence, the p53 signaling pathway, leukocyte transendothelial migration and tyrosine metabolism. Coexpression analyses showed that 561 DE lncRNAs were associated with DE mRNAs. A total of 58 lncRNA-miRNA-mRNA target pairs were confirmed in this lncRNA‒miRNA‒mRNA network, comprising 10 mRNAs, 13 miRNAs and 38 lncRNAs. CONCLUSIONS: We found specific lncRNAs and mRNAs in the hippocampus of natural aging model rats, as well as abnormal regulatory ceRNA networks. Our outcomes help explain the pathogenesis of brain aging and provide direction for further research.


Asunto(s)
MicroARNs , ARN Largo no Codificante , Envejecimiento , Animales , Redes Reguladoras de Genes , Hipocampo/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Receptores Activados del Proliferador del Peroxisoma/genética , Receptores Activados del Proliferador del Peroxisoma/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , ARN Mensajero/metabolismo , Ratas , Reproducibilidad de los Resultados , Proteína p53 Supresora de Tumor/genética , Tirosina
8.
Plant Cell ; 31(12): 2947-2972, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31628167

RESUMEN

Flowers are essential but vulnerable plant organs, exposed to pollinators and florivores; however, flower chemical defenses are rarely investigated. We show here that two clustered terpene synthase and cytochrome P450 encoding genes (TPS11 and CYP706A3) on chromosome 5 of Arabidopsis (Arabidopsis thaliana) are tightly coexpressed in floral tissues, upon anthesis and during floral bud development. TPS11 was previously reported to generate a blend of sesquiterpenes. By heterologous coexpression of TPS11 and CYP706A3 in yeast (Saccharomyces cerevisiae) and Nicotiana benthamiana, we demonstrate that CYP706A3 is active on TPS11 products and also further oxidizes its own primary oxidation products. Analysis of headspace and soluble metabolites in cyp706a3 and 35S:CYP706A3 mutants indicate that CYP706A3-mediated metabolism largely suppresses sesquiterpene and most monoterpene emissions from opening flowers, and generates terpene oxides that are retained in floral tissues. In flower buds, the combined expression of TPS11 and CYP706A3 also suppresses volatile emissions and generates soluble sesquiterpene oxides. Florivory assays with the Brassicaceae specialist Plutella xylostella demonstrate that insect larvae avoid feeding on buds expressing CYP706A3 and accumulating terpene oxides. Composition of the floral microbiome appears also to be modulated by CYP706A3 expression. TPS11 and CYP706A3 simultaneously evolved within Brassicaceae and form the most versatile functional gene cluster described in higher plants so far.plantcell;31/12/2947/FX1F1fx1.


Asunto(s)
Transferasas Alquil y Aril/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Flores/metabolismo , Terpenos/antagonistas & inhibidores , Transferasas Alquil y Aril/genética , Animales , Arabidopsis/enzimología , Arabidopsis/genética , Arabidopsis/microbiología , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Sistema Enzimático del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450/genética , Flores/genética , Flores/microbiología , Expresión Génica , Larva , Microbiota , Modelos Moleculares , Simulación del Acoplamiento Molecular , Monoterpenos/metabolismo , Mariposas Nocturnas , Familia de Multigenes , Filogenia , Sesquiterpenos/metabolismo , Terpenos/química , Terpenos/metabolismo , Nicotiana/metabolismo , Levaduras/metabolismo
9.
Bioprocess Biosyst Eng ; 45(8): 1407-1419, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35871697

RESUMEN

The production of ε-poly-L-lysine (ε-PL) from cassava bagasse hydrolysate (CBH) by Streptomyces albulus US3-18 was investigated in this study. With 30 g/L glucose from CBH, 1.30 g/L ε-PL and 10.68 g/L biomass were obtained in shake flask fermentation. Interestingly, the two values were increased by 14.0% and 21.5%, respectively, compared to the control (1.14 g/L and 8.79 g/L). Simultaneously, the activities of four key enzymes of ε-PL synthesis during CBH fermentation were enhanced to varying degrees. In batch fermentation of 5-L bioreactor, 3.39 g/L ε-PL and 10.17 g/L DCW were harvested with 40 g/L glucose from CBH. The combination of fed-batch fermentation with two-stage pH strategy significantly increased ε-PL titer and biomass to 37.41 g/L and 41.0 g/L, respectively. Moreover, eleven volatile components were detected in CBH by GC-MS, and 6-pentyl-α-pyrone (6PP) was first identified as the most abundant volatile ingredient. The results in CBH fermentation demonstrated that S. albulus US3-18 exhibited high tolerance to these volatile byproducts. Using ICP-MS, the calcium concentration in CBH was determined as 195.0 mg/(kg hydrolyzate), and cobalt, copper, lead, chromium, mercury and arsenic were not detected. By adding 0.05 g/L CaCl2 to M3G medium, ε-PL yield was improved by 28.0%, indicating calcium was one of the factors for the enhanced ε-PL production. The study provides a reference for the efficient production of ε-PL from low-cost agricultural residues.


Asunto(s)
Manihot , Polilisina , Calcio , Carbono , Celulosa , Fermentación , Glucosa , Streptomyces
10.
Prep Biochem Biotechnol ; 52(5): 525-533, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34455924

RESUMEN

ε-Poly-l-lysine (ε-PL) is used as a natural food preservative which consists of l-lysine units connected. However, due to the expensive culture medium, the production cost of ε-PL remains high. In this study, cheap raw materials cassava starch (CS) and fish meal (FM) were employed by S. albulus FQC-24 for ε-PL production. In the single factor experiment, the maximum ε-PL production reached 0.97 g/L at 60 g/L CS and 15 g/L FM. The results of screening experiments by Plackett-Burman design showed that three main components affecting ε-PL production were CS, FM, and (NH4)2SO4. And the standardized effects of CS, FM, and (NH4)2SO4 were 0.13, -0.22, and -0.2, respectively. The optimum fermentation medium developed by response surface methodology for ε-PL production contained (g/L) CS, 67.56; FM, 14.70 and (NH4)2SO4, 5.41. Under the optimum conditions, the ε-PL production was achieved 1.30 g/L, with 34.02% higher than that before optimization. Moreover, ε-PL productions of batch and fed-batch fermentation in a 7-L fermentor were improved to 2.13 and 17.17 g/L respectively, which increased by 0.64 and 12.2 times compared with the shake flask culture. The results indicated that FM and CS are promising substrates for the efficient production of ε-PL.


Asunto(s)
Manihot , Streptomyces , Medios de Cultivo/farmacología , Fermentación , Polilisina/farmacología , Almidón
11.
Appl Microbiol Biotechnol ; 105(2): 509-523, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33394147

RESUMEN

Ribose-5-phosphate isomerase B (RpiB) was first identified in the pentose phosphate pathway responsible for the inter-conversion of ribose-5-phosphate and ribulose-5-phosphate. Though there are seldom key enzymes in central carbon metabolic system developed as useful biocatalysts, RpiB with the advantages of wide substrate scope and high stereoselectivity has become a potential biotechnological tool to fulfill the demand of rare sugars currently. In this review, the pivotal roles of RpiB in carbon metabolism are summarized, and their sequence identity and structural similarity are discussed. Substrate binding and catalytic mechanisms are illustrated to provide solid foundations for enzyme engineering. Interesting differences in origin, physiological function, structure, and catalytic mechanism between RpiB and ribose-5-phosphate isomerase A are introduced. Moreover, enzyme engineering efforts for rare sugar production are stressed, and prospects of future development are concluded briefly in the viewpoint of biocatalysis. Aided by the progresses of structural and computational biology, the application of RpiB will be promoted greatly in the preparation of valuable molecules. KEY POINTS: • Detailed illustration of RpiB's vital function in central carbon metabolism. • Potential of RpiB in sequence, substrate scope, and mechanism for application. • Enzyme engineering efforts to promote RpiB in the preparation of rare sugars.


Asunto(s)
Isomerasas Aldosa-Cetosa , Azúcares , Isomerasas Aldosa-Cetosa/genética , Isomerasas Aldosa-Cetosa/metabolismo , Carbono , Vía de Pentosa Fosfato
12.
Proc Natl Acad Sci U S A ; 115(23): E5410-E5418, 2018 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-29784821

RESUMEN

Gossypol and related sesquiterpene aldehydes in cotton function as defense compounds but are antinutritional in cottonseed products. By transcriptome comparison and coexpression analyses, we identified 146 candidates linked to gossypol biosynthesis. Analysis of metabolites accumulated in plants subjected to virus-induced gene silencing (VIGS) led to the identification of four enzymes and their supposed substrates. In vitro enzymatic assay and reconstitution in tobacco leaves elucidated a series of oxidative reactions of the gossypol biosynthesis pathway. The four functionally characterized enzymes, together with (+)-δ-cadinene synthase and the P450 involved in 7-hydroxy-(+)-δ-cadinene formation, convert farnesyl diphosphate (FPP) to hemigossypol, with two gaps left that each involves aromatization. Of six intermediates identified from the VIGS-treated leaves, 8-hydroxy-7-keto-δ-cadinene exerted a deleterious effect in dampening plant disease resistance if accumulated. Notably, CYP71BE79, the enzyme responsible for converting this phytotoxic intermediate, exhibited the highest catalytic activity among the five enzymes of the pathway assayed. In addition, despite their dispersed distribution in the cotton genome, all of the enzyme genes identified show a tight correlation of expression. Our data suggest that the enzymatic steps in the gossypol pathway are highly coordinated to ensure efficient substrate conversion.


Asunto(s)
Gosipol/biosíntesis , Gosipol/metabolismo , Vías Biosintéticas , Gossypium/metabolismo , Isomerasas/biosíntesis , Isomerasas/metabolismo , Hojas de la Planta/metabolismo , Sesquiterpenos Policíclicos , Sesquiterpenos/metabolismo , Transcriptoma/efectos de los fármacos
13.
J Neurosci ; 39(46): 9107-9118, 2019 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-31597725

RESUMEN

Although several genes have been identified to promote axon regeneration in the CNS, our understanding of the molecular mechanisms by which mammalian axon regeneration is regulated is still limited and fragmented. Here by using female mouse sensory axon and optic nerve regeneration as model systems, we reveal an unexpected role of telomerase reverse transcriptase (TERT) in regulation of axon regeneration. We also provide evidence that TERT and p53 act downstream of c-Myc to control sensory axon regeneration. More importantly, overexpression of p53 in sensory neurons and retinal ganglion cells is sufficient to promote sensory axon and optic never regeneration, respectively. The study reveals a novel c-Myc-TERT-p53 signaling pathway, expanding horizons for novel approaches promoting CNS axon regeneration.SIGNIFICANCE STATEMENT Despite significant progress during the past decade, our understanding of the molecular mechanisms by which mammalian CNS axon regeneration is regulated is still fragmented. By using sensory axon and optic nerve regeneration as model systems, the study revealed an unexpected role of telomerase reverse transcriptase (TERT) in regulation of axon regeneration. The results also delineated a c-Myc-TERT-p53 pathway in controlling axon growth. Last, our results demonstrated that p53 alone was sufficient to promote sensory axon and optic nerve regeneration in vivo Collectively, the study not only revealed a new mechanisms underlying mammalian axon regeneration, but also expanded the pool of potential targets that can be manipulated to enhance CNS axon regeneration.


Asunto(s)
Axones/metabolismo , Ganglios Espinales/metabolismo , Regeneración Nerviosa , Nervio Óptico/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Telomerasa/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Células Cultivadas , Femenino , Ratones Endogámicos C57BL
14.
J Cell Biochem ; 120(11): 18600-18607, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31338882

RESUMEN

Lung cancer (especially, non-small cell lung cancer [NSCLC]) is one of the most malignant cancers in the world. Hinesol is the major component of the essential oil of Atractylodes lancea (Thunb.) DC and possesses the most promising anticancer function. However, the effects and molecular mechanism of hinesol on antiproliferation in NSCLC cells has not been well understood. In this study, we found that hinesol effectively inhibited the A549 and NCI-H1299 cells in a dose- and time-dependent manner by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay. In addition, hinesol induced cell cycle arrest at G0/G1 phase and apoptosis assessed by flow cytometry in A549 cells. Furthermore, Western blot analysis showed that hinesol decreased phosphorylation of mitogen-activated protein kinase, extracellular signal-regulated kinase, IκBα, and p65 inhibited the expressions of Bcl-2, cyclin D1 and upregulated the expression of Bax. Based on these results, hinesol might be a potential drug candidate of anti-NSCLC for therapy.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Atractylodes/química , Proliferación Celular/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , FN-kappa B/metabolismo , Sesquiterpenos/farmacología , Compuestos de Espiro/farmacología , Células A549 , Proteínas Reguladoras de la Apoptosis/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Estructura Molecular , Extractos Vegetales/farmacología , Fase de Descanso del Ciclo Celular/efectos de los fármacos , Sesquiterpenos/química , Compuestos de Espiro/química , Factores de Tiempo
15.
Appl Microbiol Biotechnol ; 103(6): 2483-2492, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30685813

RESUMEN

Ionic liquids (ILs) have been applied as an environmentally friendly solvent in the pretreatment of lignocellulosic biomass for more than a decade. The ILs involved pretreatment processes for cellulases mediated saccharification lead to both the breakdown of cellulose crystallinity and the decrease of lignin content, thereby improving the solubility of cellulose and the accessibility of cellulase. However, most cellulases are partially or completely inactivated in the presence of even low amount of ILs. Immobilized cellulases are found to perform improved stability and higher apparent activity in practical application compared with its free counterparts. Enzyme immobilization therefore has become a promising way to relieve the deactivation of cellulase in ILs. Various immobilization carriers and methods have been developed and achieved satisfactory results in improving the stability, activity, and recycling of cellulases in IL pretreatment systems. This review aims to provide detailed introduction of immobilization methods and carrier materials of cellulase, including natural polysaccharides, synthetic polymers, inorganic materials, magnetic materials, and newly developed composite materials, and illustrate key methodologies in improving the performance of cellulase in the presence of ILs. Especially, novel materials and concepts from the recently representative researches are focused and discussed comprehensively, and future trends in immobilization of cellulases in non-natural ILs environments are speculated in the end.


Asunto(s)
Celulasa/metabolismo , Enzimas Inmovilizadas/metabolismo , Líquidos Iónicos/química , Biomasa , Celulosa/metabolismo , Hidrólisis , Lignina/metabolismo , Polisacáridos/química , Solventes
16.
Clin Exp Pharmacol Physiol ; 46(1): 75-85, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30221384

RESUMEN

Diabetic retinopathy (DR) is one of the most frequently occurring microvascular complications of diabetes. Recent evidence indicates that epidermal growth factor receptors (EGFRs) are critical pathogenic players in non-neoplastic diseases, including diabetic cardiomyopathy and DR. However, the precise pathogenic mechanism of EGFR in DR has yet to be fully understood. In this study, we developed a type 1 diabetic early-stage retinopathy mouse model using injections of streptozotocin and an oxygen-induced end-stage diabetic retinopathy (OIR) model characterized by hypoxia-induced revascularization. We tested the hypothesis that the pathogenesis of DR can be reduced by the classic EGFR inhibitor, AG1478, in the mouse models. Our data indicated that treatment of AG1478 prevented retinal dysfunction, and reduced impairment of retinal structures as well as mitochondrial structures in retinal blood vessels in diabetic mice. Furthermore, AG1478 reduced neovascular tufts formation but had no effects on revascularization at the avascular sites when compared to untreated littermates in the OIR model. Our findings provide strong evidence that EGFR critically promoted retinal dysfunction, retinal structural impairment, and retinal vascular abnormalities in models of DR. We conclude that EGFR can be a potential important therapeutic target for treatment of DR.


Asunto(s)
Retinopatía Diabética/patología , Retinopatía Diabética/fisiopatología , Receptores ErbB/antagonistas & inhibidores , Neovascularización Patológica/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Quinazolinas/farmacología , Tirfostinos/farmacología , Animales , Progresión de la Enfermedad , Femenino , Inflamación/patología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Masculino , Ratones , Mitocondrias/efectos de los fármacos , Mitocondrias/patología , Inhibidores de Proteínas Quinasas/uso terapéutico , Quinazolinas/uso terapéutico , Vasos Retinianos/efectos de los fármacos , Vasos Retinianos/patología , Tirfostinos/uso terapéutico
17.
Mediators Inflamm ; 2018: 4934592, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30057486

RESUMEN

Inflammation is a key factor in the pathogenesis of ALI. Therefore, suppression of inflammatory response could be a potential strategy to treat LPS-induced lung injury. Osthole, a natural coumarin extract, has been reported to protect against acute kidney injury through an anti-inflammatory mechanism, but its effect on ALI is poorly understood. In this study, we investigated whether osthole ameliorates inflammatory sepsis-related ALI. Results from in vitro studies indicated that osthole treatment inhibited the LPS-induced inflammatory response in mouse peritoneal macrophages through blocking the nuclear translocation of NF-κB. Consistently, the in vivo studies indicated that osthole significantly prolonged the survival of septic mice which was accompanied by inflammation suppression. In the ALI mouse model, osthole effectively inhibited the development of lung tissue injury, leukocytic recruitment, and cytokine productions, which was associated with inhibition of NF-κB nuclear translocation. These findings provide evidence that osthole was a potent inhibitor of NF-κB and inflammatory injury and suggest that it could be a promising anti-inflammatory agent for therapy of septic shock and acute lung injury.


Asunto(s)
Lesión Pulmonar Aguda/prevención & control , Cumarinas/farmacología , Inflamación/tratamiento farmacológico , FN-kappa B/metabolismo , Transporte Activo de Núcleo Celular , Lesión Pulmonar Aguda/inducido químicamente , Adyuvantes Inmunológicos/farmacología , Animales , Antiinflamatorios/farmacología , Líquido del Lavado Bronquioalveolar , Ensayo de Inmunoadsorción Enzimática , Lesión Pulmonar/metabolismo , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Reacción en Cadena en Tiempo Real de la Polimerasa , Factor de Necrosis Tumoral alfa/metabolismo
18.
Sensors (Basel) ; 18(9)2018 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-30200347

RESUMEN

In energy harvesting wireless sensor networks (EHWSNs), the energy tension of the network can be relieved by obtaining the energy from the surrounding environment, but the cost on hardware cannot be ignored. Therefore, how to minimize the cost of energy harvesting hardware to reduce the network deployment cost, and further optimize the network performance, is still a challenging issue in EHWSNs. In this paper, an energy conserving and transmission radius adaptive (ECTRA) scheme is proposed to reduce the cost and optimize the performance of solar-based EHWSNs. There are two main innovations of the ECTRA scheme. Firstly, an energy conserving approach is proposed to conserve energy and avoid outage for the nodes in hotspots, which are the bottleneck of the whole network. The novelty of this scheme is adaptively rotating the transmission radius. In this way, the nodes with maximum energy consumption are rotated, balancing energy consumption between nodes and reducing the maximum energy consumption in the network. Therefore, the battery storage capacity of nodes and the cost on hardware. Secondly, the ECTRA scheme selects a larger transmission radius for rotation when the node can absorb enough energy from the surroundings. The advantages of using this method are: (a) reducing the energy consumption of nodes in near-sink areas, thereby reducing the maximum energy consumption and allowing the node of the hotspot area to conserve energy, in order to prevent the node from outage. Hence, the network deployment costs can be further reduced; (b) reducing the network delay. When a larger transmission radius is used to transmit data in the network, fewer hops are needed by data packet to the sink. After the theoretical analyses, the results show the following advantages compared with traditional method. Firstly, the ECTRA scheme can effectively reduce deployment costs by 29.58% without effecting the network performance as shown in experiment analysis; Secondly, the ECTRA scheme can effectively reduce network data transmission delay by 44⁻71%; Thirdly, the ECTRA scheme shows a better balance in energy consumption and the maximum energy consumption is reduced by 27.89%; And lastly, the energy utilization rate is effectively improved by 30.09⁻55.48%.

19.
Prep Biochem Biotechnol ; 48(3): 257-263, 2018 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-29355459

RESUMEN

Erythritol, a well-known natural sweetener, is mainly produced by microbial fermentation. Various metal ions (Al3+, Cu2+, Mn2+, and Ni2+) were added to the culture medium of Trichosporonoides oedocephalis ATCC 16958 at 30 mg/L in shake flask cultures. Compared with controls, Cu2+ increased the erythritol content by 86% and decreased the glycerol by-product by 31%. After 48 hr of shake flask culture, sodium dodecyl sulfate polyacrylamide gel electrophoresis showed that expression levels of erythrose reductase (ER) in the presence of 30 mg/L CuSO4 · 5H2O were higher than those obtained after treatment with other examined metal ions. Furthermore, after 108 hr of batch culture in a 5-L bioreactor, supplementation with 30 mg/L of CuSO4 · 5H2O increased the specific erythritol content by 27%. Further studies demonstrated that ER activity under 30 mg/L CuSO4 · 5H2O supplementation in a fermentor was overtly increased compared with the control after 60 hr, while glycerol-3-phosphate dehydrogenase activity was clearly reduced in most of the fermentation process. Furthermore, the NADPH/NADP ratio was slightly lower in T. oedocephalis cells treated with Cu2+ compared with control cells. These results provide further insights into Cu2+ effects on erythritol biosynthesis in T. oedocephalis and should improve the industrial production of erythritol by biological processes.


Asunto(s)
Basidiomycota/enzimología , Técnicas de Cultivo Celular por Lotes/métodos , Eritritol/metabolismo , Microbiología Industrial/métodos , NADP/metabolismo , Edulcorantes/metabolismo , Aldehído Reductasa/metabolismo , Basidiomycota/metabolismo , Reactores Biológicos/microbiología , Cationes/metabolismo , Fermentación , Glicerol/metabolismo , Glicerolfosfato Deshidrogenasa/metabolismo , Metales/metabolismo
20.
Bioinformatics ; 31(22): 3700-2, 2015 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-26227144

RESUMEN

UNLABELLED: Synthetic fusion proteins have shown great potential in various biotechnological and (bio)pharmaceutical applications. They usually contain more than two protein domains joined by a linker peptide sequence which is often selected intuitively or in ad hoc manner. Thus, we developed an integrated web-based system, SynLinker, to provide appropriate linker candidates for constructing fusion proteins. We compiled a total of 2260 linker sequences comprising of natural linkers extracted from a set of non-redundant multi-domain proteins in Protein Data Bank and artificial/empirical linkers collected from literature and patents. Multiple query interface allows users to search for the desired linker candidates based on selection criteria and their preferences. In addition, a selected linker can be combined with two domain structures which are uploaded and appended at its N and C terminals, thereby predicting a de novo structure of the fusion protein. Hence, SynLinker can serve as a systematic tool for researchers who are interested in designing synthetic fusion proteins. AVAILABILITY AND IMPLEMENTATION: SynLinker is freely available at http://bioinfo.bti.a-star.edu.sg/synlinker. CONTACT: cheld@nus.edu.sg SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Proteínas Recombinantes de Fusión/síntesis química , Programas Informáticos , Secuencia de Aminoácidos , Bases de Datos de Proteínas , Humanos , Interfaz Usuario-Computador
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