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Inspired by the metal-oxo cluster structural feature and charge separation behaviour of the oxygen evolving center (OEC) in photosystem II (PS-II) under photoirradiation, a new crystalline photochromic polyoxomolybdate, MV2 [ß-Mo8 O26 ] (1, MV=methyl viologen cation), is designed as a biomimetic oxygen evolution reaction (OER) catalyst in neutral electrolytes. After photoinduced electron transfer (PIET) with colour change from colourless to grey, it remains in an ultra-stable charge-separated state over a year under ambient conditions. The observed overpotential at 10â mA â cm-2 and Tafel slope decrease by 49â mV and 62.8â mV â dec-1 after coloration, respectively. The outstanding OER performance of the coloured state in neutral electrolytes even outperforms the commercial RuO2 benchmark. Experimental and theoretical studies show that oxygen holes within polyanions after irradiation serve as sites for enhancing direct O-O coupling, thus effectively promoting OER. This is the first successful application of electron-transfer photochromism to realize OER activity gain.
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Poplar is an important afforestation and ornamental tree species in Northeast China. The distribution area of saline-alkali land is approximately 765 hm2 in Northeast China. The breeding of saline-alkali-resistant transgenic trees could be an effective method of afforestation in saline-alkali land. WRKY transcription factors play a crucial role in abiotic stress. In this study, we analyzed the genetic stability of the two-year-old PsnWRKY70 transgenic poplars. The results showed that PsnWRKY70 of transgenic poplars had been expressed stably and normally at the mRNA level. The gene interference expression (RE) lines had no significant effect on the growth of PsnWRKY70 under NaHCO3 stress, and the alkali damage index of RE lines was significantly lower than that of WT and overexpression (OE) lines at day 15 under NaHCO3 stress. POD activity was significantly higher in RE lines than in WT. The MDA content of the RE line was lower than that of the WT line. Transcriptome analysis showed that RE lines up-regulated genes enriched in cell wall organization or biogenesis pathway-related genes such as EXPA8, EXPA4, EXPA3, EXPA1, EXPB3, EXP10, PME53, PME34, PME36, XTH9, XTH6, XTH23, CESA1, CESA3, CES9; FLA11, FLA16 and FLA7 genes. These genes play an important role in NaHCO3 stress. Our study showed that the interference expression of the PsnWRKY70 gene can enhance the tolerance of NaHCO3 in poplar.
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Populus , Populus/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Melhoramento Vegetal , Estresse Fisiológico/genética , Álcalis/metabolismoRESUMO
To investigate the effects of apigenin on the injury caused by oxygen and glucose deprivation in neurons and the underlying mechanisms, primary cultured rat hippocampal neurons were incubated with apigenin for 90 min before a 2-h oxygen and glucose deprivation followed by a 24-h reperfusion (OGD/R). Subsequently, cell viability, lactate dehydrogenase (LDH) leakage rate, apoptotic rate of neurons and activity of the sodium pump were assessed. In addition, activity of the sodium pump was also examined in the hippocampus of SD rats injected intraperitoneally with apigenin 90 min before a 10-min global cerebral ischemia/24-h reperfusion. The results showed that cell viability and activity of the sodium pump markedly decreased but LDH leakage rate and apoptotic rate significantly increased in OGD/R-treated neurons. However, pretreatment with apigenin (20-50µmol/L) reversed the changes dose-dependently. Compared to sham controls, activity of the sodium pump was significantly suppressed in global ischemia/reperfusion rats; application of apigenin (200mg/kg) restored the activity of the sodium pump. Furthermore, the neuroprotective effect of apigenin was blocked partly by the sodium pump inhibitor ouabain. Our findings provide the evidence that apigenin has a neuroprotective effect against OGD/R injury and the protective effect may be associated with its ability to improve sodium pump activity.
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Apigenina/farmacologia , Hipocampo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Glucose/metabolismo , Hipocampo/metabolismo , Masculino , Neurônios/metabolismo , Oxigênio/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismoRESUMO
OBJECTIVE: To study the effect of hyperoxic exposure on the dynamic expression of heme oxygenase-1 (HO-1) and glutamate-L-cysteine ligase catalytic subunit (GCLC) in the lung tissue of preterm neonatal rats. METHODS: Cesarean section was performed for rats on day 21 of gestation to obtain 80 preterm rats, which were randomly divided into air group and hyperoxia group after one day of feeding. The rats in the air group were housed in room air under atmospheric pressure, and those in the hyperoxia group were placed in an atmospheric oxygen tank (oxygen concentration 85%-95%) in the same room. Eight rats each were selected from each group on days 1, 4, 7, 10, and 14, and lung tissue samples were collected. Hematoxylin and eosin staining was used to observe the pathological changes of lung tissue at different time points after air or hyperoxic exposure. Western blot and RT-qPCR were used to measure the protein and mRNA expression of HO-1 and GCLC in the lung tissue of preterm rats at different time points after air or hyperoxic exposure. RESULTS: Compared with the air group, the hyperoxia group had a significant reduction in the body weight (P<0.05). Compared with the air group, the hyperoxia group had structural disorder, widening of alveolar septa, a reduction in the number of alveoli, and simplification of the alveoli on the pathological section of lung tissue. Compared with the air group, the hyperoxia group had significantly lower relative mRNA expression of HO-1 in the lung tissue on day 7 and significantly higher expression on days 10 and 14 (P<0.05). Compared with the air group, the hyperoxia group had significantly lower mRNA expression of GCLC in the lung tissue on days 1, 4, and 7 and significantly higher expression on day 10 (P<0.05). Compared with the air group, the hyperoxia group had significantly higher protein expression of HO-1 in the lung tissue on all days, and the protein expression of GCLC had same results as HO-1, except on day 1 (P<0.05). CONCLUSIONS: Hyperoxia exposure may lead to growth retardation and lung developmental retardation in preterm rats. Changes in the protein and mRNA expression of HO-1 and GCLC in the lung tissue of preterm rats may be associated with the pathogenesis of hyperoxia-induced lung injury in preterm rats.
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Hiperóxia , Animais , Animais Recém-Nascidos , Domínio Catalítico , Cesárea , Cisteína , Feminino , Glutamatos , Heme Oxigenase-1 , Humanos , Recém-Nascido , Pulmão , Gravidez , Ratos , Ratos Sprague-DawleyRESUMO
Objective To observe the protective effects of Bushen Jiedu Recipe (BJR) on radia- tion induced hematopoietic injury. Methods C57BL/10J mice TLR4 gene (TLR4 +/+) and knockout mice (TLR4 -/-) were randomly divided into 3 groups, the blank control group, the radiation model group, the BJR group. Sampling was respectively performed at day 1 , 14, and 30 after radiation. The general condi- tion of mice was observed. White blood cell (WBC) , red blood cell ( RBC) , and platelet ( PLT) were counted in each group. Thigh bone of mice was collected for bone marrow specimen. Bone marrow slice was prepared. Pathomorphological changes were observed under electron microscope. Results Com- pared with the blank control group, WBC, RBC, and PLT all decreased or showed a decreasing tendency after one day radiation. RBC and PLT significantly decreased after 14 days of radiation (P <0. 01 , P < 0. 05). Counts of WBC and RBC were higher in the TLR4 +/+ BJR group than in the rest 2 groups (P < 0. 01 , P <0. 05). No statistical difference in RBC or PLT between mice after 30 days of radiation and mice in the blank control group (P >0. 05). PLT count in the TLR4 +/+ BJR group was most approximate to the normal value. WBC count obviously increased, but still with statistical difference as compared with the blank control group (P <0.01). WBC count recovered most rapidly in the TLR4 +/+ BJR group. Results under light microscope showed the structure of bone marrow was injured to different degrees in all mice except those in the TLR4 +/+ BJR group. Conclusion BJR could attenuate radiation induced hematopoi- etic injury possibly through TLR4 signal pathway, thus playing significant radioprotective roles.
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Medicamentos de Ervas Chinesas , Sistema Hematopoético , Lesões por Radiação , Receptor 4 Toll-Like , Animais , Medula Óssea , Medicamentos de Ervas Chinesas/uso terapêutico , Transplante de Células-Tronco Hematopoéticas , Sistema Hematopoético/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Lesões por Radiação/prevenção & controle , Receptor 4 Toll-Like/genéticaRESUMO
The X-ray fluorescence well logging technology is a significant method that can make quantitative analysis orsemi-quantitative analysis on the wellface. This method is very important to mineral exploration. The spectrum shifting is often observed in the X-rayfluorescence well logging because the temperature in the well changes acutely. The hardware is used to release the spectrum shifting and the software method is used to rescale the tiny spectrum shifting. There are too manyspectra to be rescaled in a well logging task by manually. In this paper, an auto method to rescale spectrum shifting, via the expert system model which is based on the special process to rescale spectrum shifting in manual, is presented. The symmetric zero-area conversion method, which is not sensitive to the changes of the baseline, is used to research the peaks. And then, the characteristic peaks will be identified by the standard errors, automatically. The prior knowledge (the last energy scale) and the gauss probability density function are used to analyze the peaks qualitatively and confirm the energy of characteristic peaks. Then the least square method is applied energy calibration. The singular deviation point, away from the calibrationline, will be rejected and the energy ratio will be obtained again. This method is applied for rescaling spectrum shifting in 322 spectra and obtains a satisfactory achievement.
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We reported a one-pot, no added seeding and green method to synthesize gold nanoflowers, in which HAuC4 and H2O2 were added one by one into the alkaline protocatechuic aldehyde solution at room temperature. Au(III) was partially reduced by protocatechuic aldehyde to produce primary Au nanocrystals, and then Au nanocrystals agglomerated into loose flower-like nanoparticles as seeds, which catalyzed H2O2 reduction of the residual Au(III), thus accelerating the formation of compact 3D gold nanoflowers. The key synthesis strategy was to use protocatechuic aldehyde as a structure-induced agent to influence the growth of gold nanoflowers. The pH value of growth solution could tune the size and/or morphology of gold nanoflowers through its influence on the adhesion force of protocatechuic aldehyde on gold surfaces and the species type of Au(III) complexes. When the pH value of growth solution was above 7.26 (the pKa of protocatechuic aldehyde), the flower-like of gold nanostructural architectures with different sizes could be fabricated. The obtained gold nanoflowers had a large dimension of 198 and 157 nm at the pH of 7.6 and 8, respectively. Size control of gold nanoflowers can be accomplished in the growth solutions of pH 9.4-12.0 with a similar diameter around 60 nm. The as-synthesized gold nanoflowers exhibited good stability and have the prospects for surface-enhanced Raman scattering enhancement.
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Ouro/química , Nanoestruturas/química , Nanotecnologia/métodos , Aldeídos , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Análise Espectral RamanRESUMO
A series of proof-of-concept models of polyoxomolybdates with different protonated disubstituted aniline counterions and the same ß-Mo8O26 polyanion were synthesized to study the mechanism governing the formation of the intermolecular charge transfer (inter-CT) band.
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Excessive UVB exposure increased the production of reactive oxygen species (ROS), leading to oxidative damage and epidermal inflammation. To enhance UVB protection effect, a strong phenolic antioxidant, ferulic acid (FA) was designed onto HA via a free radical mediated method. Our previous work has confirmed its structural characterization and in vitro antioxidant. The aim of this study was to evaluate its protective effects against UVB-induced damage in human HaCaT cells. We observed a significant reduction in cell viability to 57.43 % following UVB exposure at a dose of 80 mJ/cm2. However, pretreatment with FA-HA (250 to 2000 µg·mL-1) significantly attenuated cytotoxicity in a dose-dependent manner. Furthermore, FA-HA was found to suppress the intracellular generation of ROS and up-regulated the expression of the antioxidant enzyme superoxide dismutase (SOD). The elevated levels of pro-inflammatory cytokines, including interleukin-1 beta (IL-1ß), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-α) as well as the mRNA expression of matrix metalloproteinase-1/9 (MMP-1/9) induced by UVB irradiation, were also effectively reduced by FA-HA. Additionally, FA-HA treatment decreases the phosphorylation of mitogen-activated protein kinase (MAPK) and activator protein-1 (AP-1), ultimately preventing apoptosis. These findings suggest that FA-HA is a promising candidate for UVB protection in skincare formulations.
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Sobrevivência Celular , Ácidos Cumáricos , Células HaCaT , Ácido Hialurônico , Espécies Reativas de Oxigênio , Raios Ultravioleta , Humanos , Ácidos Cumáricos/farmacologia , Ácidos Cumáricos/química , Raios Ultravioleta/efeitos adversos , Sobrevivência Celular/efeitos dos fármacos , Ácido Hialurônico/farmacologia , Ácido Hialurônico/química , Espécies Reativas de Oxigênio/metabolismo , Citocinas/metabolismo , Antioxidantes/farmacologia , Antioxidantes/química , Protetores contra Radiação/farmacologia , Protetores contra Radiação/química , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Superóxido Dismutase/metabolismo , Polímeros/química , Polímeros/farmacologiaRESUMO
A series of proof-of-concept models with different degrees of hydration in the same donor-acceptor system were obtained through a functional motif-oriented structural design and screening strategy. The effect of water molecules on photoinduced electron transfer was explored from a crystallographic perspective for the first time. The reasons for the structural differences caused by different degrees of hydration were also discussed.
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Elétrons , Água , Transporte de ElétronsRESUMO
Leaves are one of the vegetative organs of plants that are essential for plant growth and development. PIN-FORMED (PINs) gene is an indoleacetic acid (IAA) transporter that plays a critical role in leaf development. To determine the function of BpPIN3 in leaf polarity formation in Betula pendula, the transgenic lines with BpPIN3 overexpression (OE) and BpPIN3-reduced expression (RE) were analyzed using the Agrobacterium-mediated method. The RE lines displayed the characteristics of leaf margin adaxial upward curling, with lower expression of BpPIN3 resulting in greater rolling. Tissue localization of IAA in the auxin GUS reporter system proved that auxin in the RE was mainly distributed in the secondary veins, palisade tissues, and epidermal cells in the leaf margin area. The auxin content in the leaf margin area was significantly greater than that in the main vein tissue. The cell density of the palisade tissue and the ratio of palisade tissue to spongy tissue in the curled leaf margin of the RE lines were found to be significantly decreased. RNA-seq analysis revealed that the RE hormone-signaling pathway genes were significantly enriched compared with those of the OE and WT lines; in particular, the auxin response-related genes SAURs (i.e., SAUR23, SAUR24, SAUR28, and SAUR50) and GH3.10 were found to be significantly upregulated. qRT-PCR analysis indicated that BpPIN3 expression at the leaf margin was significantly lower than that near the main vein in the RE lines. In contrast, the expression levels of SAURs and GH3.10 were significantly higher than those near the midrib. In conclusion, BpPIN3 regulates the expression of auxin response-related genes and the polar transport of auxin to change the polar form of the proximal and distal axes of birch leaves.
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The fruit juice food industry produces huge waste annually, mainly Citrus peel and seeds. We investigated their chemical composition using hydrophilic interaction chromatography (HILIC-) and reverse phase liquid chromatography tandem mass spectrometry (RPLC-MS/MS), revealing 277 compounds, mainly containing flavonoids and limonoids. As the primary representative component in Citrus waste, limonin was selected to be explored new bio-functions. We applied Zebrafish larvae to study the metabolomic response invoked by limonin. The differential metabolites (DMs) varied depending on the exposing concentration of limonin. Enrichment analysis indicated that the identified DMs related to inflammation and neurologic disorders, including epilepsy which were newly discovered for limonoids and Citrus waste. Limonin was found to restore amino acids disorder to take neuroprotection against epilepsy. Our findings provided a new bio-function and purpose for Citrus waste and limonoids. Also, we demonstrated a concise case to repurpose food waste for new applications under metabolome investigation.
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Citrus , Limoninas , Eliminação de Resíduos , Aminoácidos/análise , Animais , Citrus/química , Frutas/química , Limoninas/análise , Espectrometria de Massas em Tandem , Peixe-Zebra/metabolismoRESUMO
1,2,3,4,6-Penta-O-galloyl-ß-D-glucopyranose (ß-PGG) is a compound commonly available in vegetables and fruits. It exhibited potential inhibition of α-glucosidase and hypoglycemic effect in vivo. This study explored its dynamics properties inhibiting α-glucosidase by Lineweaver - Burk plots, spectral analysis, docking analysis, and molecular dynamics simulations. ß-PGG showed a mix-type inhibition when it was interacting with α-glucosidase. The fluorescence quenching indicated that the PGG-glucosidase complex formed in a spontaneous exothermic process and was driven by enthalpy. The synchronous fluorescence and ECD spectra indicate that ß-PGG induced and changed the enzyme conformation in the complex formation. Docking results revealed multiple hydrogen bonds between the phenols and the amino acid residues. Further dynamic simulations indicated that the residues Asp345, Phe153, Arg435, Glu300, Pro305, and Phe296 played a more critical role in the interactions between ß-PGG and α-glucosidase.
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Taninos Hidrolisáveis , Polifenóis , alfa-Glucosidases , Dieta , Taninos Hidrolisáveis/farmacologia , Simulação de Acoplamento Molecular , alfa-Glucosidases/metabolismoRESUMO
Insulin mimic can promote transporting glucose to muscle tissue and accelerate glucose consumption. It is commonly occurring in many functional foods or traditional medicines. Anti-diabetes molecules from food sources are highly safe and suitable for long-term use to prevent early diabetes. The leaves of Acer truncatum was found glucose uptake promotion in our phenotypic screening. However, its bioactive components and mechanism are still unclear. We collected leaves from trees of different ages (2, 3, 4, 7 and 11 years old) and profiled the ingredients by LC-MS/MS. The essential active component (myricitrin) was acquired following bio-guide on a whole organism Zebrafish (Danio rerio). Its content in the leaves was not affected by tree ages. Therefore, myricitrin can serve as a quality mark for functional foods derived from A. truncatum leaves. The transcriptomic and metabolomic analysis in Zebrafish explored the differentially expressed genes and metabolites. Based on joint-pathway enrichment and qRT-PCR verification, the critical bioactive component myricitrin was found to affect toll-like receptors signaling pathways to regulate glucose uptake. Our findings disclosed a bioactive marker (myricitrin) in A. truncatum leaves and explored its regulation mechanism, which rationalized the anti-diabetes function of the herbal food.
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The coexistence of multiferroic orders has attracted increasing attention for its potential applications in multiple-state memory, switches, and computing, but it is still challenging to design single-phase crystalline materials hosting multiferroic orders at above room temperature. By utilizing versatile ABX3-type perovskites as a structural model, we judiciously introduced a polar organic cation with easily changeable conformations into a tetrafluoroborate-based perovskite system, and successfully obtained an unprecedented molecular perovskite, (homopiperazine-1,4-diium)[K(BF4)3], hosting both ferroelectricity and ferroelasticity at above room temperature. By using the combined techniques of variable-temperature single-crystal X-ray structural analyses, differential scanning calorimetry, and dielectric, second harmonic generation, and piezoresponse force microscopy measurements, we demonstrated the domain structures for ferroelectric and ferroelastic orders, and furthermore disclosed how the delicate interplay between stepwise changed dynamics of organic cations and cooperative deformation of the inorganic framework induces ferroelectric and ferroelastic phase transitions at 311 K and 455 K, respectively. This instance, together with the underlying mechanism of ferroic transitions, provides important clues for designing advanced multiferroic materials based on organic-inorganic hybrid crystals.
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Hydrogen sulfide (H2S) is a gaseous signaling molecule that plays multiple roles in plant development. However, whether endogenous H2S plays a role in fruit ripening in tomato is still unknown. In this study, we show that the H2S-producing enzyme L-cysteine desulfhydrase SlLCD1 localizes to the nucleus. By constructing mutated forms of SlLCD1, we show that the amino acid residue K24 of SlLCD1 is the key amino acid that determines nuclear localization. Silencing of SlLCD1 by TRV-SlLCD1 accelerated fruit ripening and reduced H2S production compared with the control. A SlLCD1 gene-edited mutant obtained through CRISPR/Cas9 modification displayed a slightly dwarfed phenotype and accelerated fruit ripening. This mutant also showed increased cysteine content and produced less H2S, suggesting a role of SlLCD1 in H2S generation. Chlorophyll degradation and carotenoid accumulation were enhanced in the SlLCD1 mutant. Other ripening-related genes that play roles in chlorophyll degradation, carotenoid biosynthesis, cell wall degradation, ethylene biosynthesis, and the ethylene signaling pathway were enhanced at the transcriptional level in the lcd1 mutant. Total RNA was sequenced from unripe tomato fruit treated with exogenous H2S, and transcriptome analysis showed that ripening-related gene expression was suppressed. Based on the results for a SlLCD1 gene-edited mutant and exogenous H2S application, we propose that the nuclear-localized cysteine desulfhydrase SlLCD1 is required for endogenous H2S generation and participates in the regulation of tomato fruit ripening.
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Sodium benzoate (SB) is widely used as a preservative in food industry, and bovine serum albumin (BSA) is a major carrier protein similar to human serum albumin (HSA), the study of the binding between the two has great significance on human health. In this paper, we systematically investigated the binding of SB and BSA under the simulated physiological conditions combining with various common analytical methods, e.g., fluorescence, UV-vis absorption, synchronous fluorescence and circular dichroism (CD) spectra, as well as molecular docking method. The fluorescence quenching measurements were respectively carried out at 298 K, 303 K and 308 K using the Stern-Volmer method. The results reveal that ground state SB-BSA complex was formed within the binding constants from 2.02 × 104 to 7.9 × 103 M-1. Meanwhile, the negative values of ΔH 0 (- 43.92 kJ mol-1) and ΔS 0 (- 111.6 J mol-1 K-1) demonstrated that both the hydrogen binding interaction and van der Waals forces contributed to stabilizing the SB-BSA complex. The site marker competitive experiments show that the SB and BSA bound at site I. Furthermore, the experimental results of UV-vis absorption, synchronous fluorescence and CD spectra indicate that the binding of SB and BSA may change the conformation of BSA. In addition, the molecular docking experiment suggests that hydrogen bond was formed in the interaction between SB and BSA.
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Four new iridoids, valeriotetrates B and C (1 and 2), 8-methylvalepotriate (3), and 1,5-dihydroxy-3,8-epoxyvalechlorine A (4), together with three known iridoids, were isolated from the roots of Valeriana wallichii. The structures of the new compounds were elucidated by analysis of 1D and 2D NMR and HRESIMS data. Compound 4 is an unusual iridoid bearing a C-10 chloro group and an oxo bridge connecting C-3 and C-8, resulting in a rigid skeleton.
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Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Iridoides/química , Iridoides/isolamento & purificação , Plantas Medicinais/química , Valeriana/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Raízes de Plantas/químicaRESUMO
BACKGROUND: Cellulolytic enzymes produced by Trichoderma reesei are widely studied for biomass bioconversion, and enzymatic components vary depending on different inducers. In our previous studies, a mixture of glucose and disaccharide (MGD) was developed and used to induce cellulase production. However, the enzymatic profile induced by MGD is still not defined, and further optimization of the enzyme cocktail is also required for efficient ethanol production from lignocellulosic biomass. RESULTS: In this study, cellulolytic enzymes produced by T. reesei Rut C30 using MGD and alkali-pretreated corn stover (APCS) as inducer were compared. Cellular secretome in response to each inducer was analyzed, which revealed a similar enzyme profile. However, significant difference in the content of cellulases and xylanase was detected. Although MGD induction enhanced ß-glucosidase production, its activity was still not sufficient for biomass hydrolysis. To overcome such a disadvantage, aabgl1 encoding ß-glucosidase in Aspergillus aculeatus was heterologously expressed in T. reesei Rut C30 under the control of the pdc1 promoter. The recombinant T. reesei PB-3 strain showed an improved ß-glucosidase activity of 310 CBU/mL in the fed-batch fermentation, 71-folds higher than that produced by the parent strain. Meanwhile, cellulase activity of 50 FPU/mL was detected. Subsequently, the crude enzyme was applied for hydrolyzing corn stover with a solid loading of 20% through separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation, respectively, for ethanol production. Better performance was observed in the SHF process, through which a total of 119.9 g/L glucose was released within 12 h for concomitant ethanol production of 54.2 g/L. CONCLUSIONS: The similar profile of cellulolytic enzymes was detected under the induction of MGD and APCS, but higher amount of cellulases was present in the crude enzyme induced by MGD. However, ß-glucosidase activity induced by MGD was not sufficient for hydrolyzing lignocellulosic biomass. High titers of cellulases and ß-glucosidase were achieved simultaneously by heterologous expression of aabgl1 in T. reesei and fed-batch fermentation through feeding MGD. We demonstrated that on-site cellulase production by T. reesei PB-3 has a potential for efficient biomass saccharification and ethanol production from lignocellulosic biomass.
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Pleomorphic xanthoastrocytoma (PXA) is a rare astrocytic neoplasm that usually arises in children and young adults. Typically, lesions of PXA are superficially located in the cerebral hemispheres. Herein, we report two extremely rare patients with PXA arising from suprasellar regions. One of the patients is a 29-year-old man admitted to our hospital with a history of progressive headache for 1month. The patient's brain MRI revealed a large tumor arising from the suprasellar cistern of the third ventricle. The second patient, a 52-year-old woman, presented with progressive dizziness and visual disturbance that had developed over the course of 1year. The MRI revealed a well-enhanced suprasellar solid mass measuring 1.4×1.2×1.4cm. Both patients underwent surgical removal of their tumors, and both patients showed similar microscopic structures and immunohistochemical phenotypes: the tumor cells were pleomorphic with mixtures of spindle-shaped, and multinuclear giant cells. In addition, eosinophilic granular bodies and xanthomatous cells were seen on section. Immunohistochemistry was positive for GFAP, S-100, and CD34, and was negative for IDH 1, CK, and Syn. The Ki-67 proliferation index was less than 1%. Silver impregnation revealed reticulin fibers surrounding the individual tumor cells, and small cell groups. Based on these findings, the two patients were diagnosed with PXA in the suprasellar region. To date, only five such patients have been reported in the literature. PXA should be included in the differential diagnosis for tumors arising in the sellar region.