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A van der Waals intrinsic ferromagnet with double magnetic atom layers is of great interest for both revealing fundamental physics and exploring promising applications in low-dimensional spintronics. Here, the magnetic and electronic properties of the van der Waals ferromagnet MgV2S4 monolayer are studied under electrostatic doping using first-principles calculations. A MgV2S4 monolayer presents the desired physical properties such as that of being a half-semiconductor with a direct bandgap of 1.21 eV and a ferromagnetic ground state, and having a high Curie temperature of 462 K. Unlike the robust ferromagnetic ground state, magnetic anisotropy and Curie temperature are sensitive to electrostatic doping. Meanwhile, the transition from a semiconductor to a half-metal and the significant improvement in conductivity under electrostatic doping make the MgV2S4 monolayer a promising candidate for low-dimensional spintronic field-effect transistors.
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A novel peroxidase-like nanozyme has been constructed by decorating two-dimensional Ti3C2Tx nanosheets (Ti3C2Tx NSs) with gold nanoparticles (AuNPs) to develop a colorimetric and photothermal dual-mode immunosensor. The Ti3C2Tx/AuNPs nanocomposite-catalyzed 3,3',5,5'-tetramethylbenzidine (TMB)-H2O2 reaction system produces the one-electron oxidation product of TMB (oxTMB), which exhibits color change and strong near-infrared (NIR) laser-driven photothermal effect at 808 nm laser irradiation. Given these characteristics, the developed immunosensor achieves ultrasensitive dual-mode detection of zearalenone (ZEN) by measuring colorimetric and photothermal signals with a microplate reader and a portable infrared thermometer, respectively. Under optimal working conditions, the limit of detection (LOD) of ZEN is 0.15 pg mL-1 for the colorimetric mode and 0.48 pg mL-1 for the photothermal mode. In the analysis of actual contaminated cereals samples, the test result of this method was consistent with that of UPLC-MS/MS. The proposed colorimetric and photothermal dual-mode immunosensor offers a new strategy for the low-cost detection of hazardous substances. The application of a widely used household infrared thermometer makes the signal readout more convenient, which provides great prospects in food safety and environment inspection applications.
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Técnicas Biosensibles , Nanopartículas del Metal , Nanocompuestos , Zearalenona , Colorimetría/métodos , Oro , Grano Comestible , Peróxido de Hidrógeno , Cromatografía Liquida , Inmunoensayo , Espectrometría de Masas en Tándem , Titanio , PeroxidasaRESUMEN
The thermoelectric, phonon transport, and electronic transport properties of two-dimensional magnet CrI3 are systematically investigated by combining density functional theory with Boltzmann transport theory. A low lattice thermal conductivity of 1.355 W m-1K-1 is presented at 300 K due to the low Debye temperature and phonon group velocity. The acoustic modes dominate the lattice thermal conductivity, and the longitudinal acoustic mode has the largest contribution of 42.31% on account of its relatively large phonon group velocity and phonon lifetime. The high band degeneracy and the peaky density of states near the conduction band minimum appear for the CrI3 monolayer, which is beneficial for forming a significantly increased Seebeck coefficient (1561 µV K-1). Furthermore, the thermoelectric figure of merit is calculated reasonably, and the value is 1.57 for the optimal n-type doping level at 900 K. N-type doping maintains a higher thermoelectric conversion efficiency than p-type doping throughout the temperature range, while the difference gradually increases as the temperature rises. Our investigation may provide some theoretical support for the application of the CrI3 monolayer in the thermoelectric field.
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The authors describe a fluorometric method for the quantitation of nucleic acids by combining (a) cycled strand displacement amplification, (b) the unique features of the DNA probe SYBR Green, and (c) polydopamine nanotubes. SYBR Green undergoes strong fluorescence enhancement upon intercalation into double-stranded DNA (dsDNA). The polydopamine nanotubes selectively adsorb single-stranded DNA (ssDNA) and molecular beacons. In the absence of target DNA, the molecular beacon, primer and SYBR Green are adsorbed on the surface of polydopamine nanotubes. This results in quenching of the fluorescence of SYBR Green, typically measured at excitation/emission wavelengths of 488/518 nm. Upon addition of analyte (target DNA) and polymerase, the stem of the molecular beacon is opened so that it can bind to the primer. This triggers target strand displacement polymerization, during which dsDNA is synthesized. The hybridized target is then displaced due to the strand displacement activity of the polymerase. The displaced target hybridizes with another molecular beacon. This triggers the next round of polymerization. Consequently, a large amount of dsDNA is formed which is detected by addition of SYBR Green. Thus, sensitive and selective fluorometric detection is realized. The fluorescent sensing strategy shows very good analytical performances towards DNA detection, such as a wide linear range from 0.05 to 25 nM with a low limit of detection of 20 pM. Graphical abstract Schematic of a fluorometric strategy for highly sensitive and selective determination of nucleic acids by combining strand displacement amplification and the unique features of SYBR Green I (SG) and polydopamine nanotubes.
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Fluorometría/métodos , Ácidos Nucleicos/análisis , Benzotiazoles , Sondas de ADN/química , ADN de Cadena Simple , Diaminas , Fluorometría/normas , Indoles , Nanotubos/química , Técnicas de Amplificación de Ácido Nucleico/métodos , Compuestos Orgánicos , Polimerizacion , Polímeros , QuinolinasRESUMEN
In this work, an aptamer-based fluorescent strategy for label-free detection of ATP was developed by using Thioflavin T (ThT) as a fluorescence indicator, which can specifically bind with G-quadruplex DNAs to generate enhanced fluorescence intensity. In the absence of ATP, the folded structure of ATP aptamer allows the intercalation of ThT to produce strong fluorescence signal. However, upon ATP binding to the aptamer where ThT intercalated, the conformational change or distortion of the aptamer is large enough to cause much less intercalation of ThT and consequently drastic suppression of the fluorescence intensity. As such, the concentration of ATP could be identified very easily by observing fluorescence changes of this sensing system. This label-free assay could be accomplished very easily and quickly with a "mix-and-detect" detection method and exhibits high sensitivity to ATP with a detection limit of 33 nM in a wide range of 0.1-1000 µM. Furthermore, this proposed method is capable of detecting ATP in human serum and cell extracts. This method offers several advantages such as simplicity, rapidity, low cost, good stability and excellent selectivity, which make it hold great potential for the detection of ATP in bioanalytical and biological studies.
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Adenosina Trifosfato/análisis , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , Colorantes Fluorescentes/química , Suero/metabolismo , Tiazoles/química , Células A549 , Adenosina Trifosfato/química , Benzotiazoles , Fluorescencia , Células HeLa , Humanos , Límite de DetecciónRESUMEN
The HDM2-p53 loop is crucial for monitoring p53 level and human pathologies. Therefore, identification of novel molecules involved in this regulatory loop is necessary for understanding the dynamic regulation of p53 and treatment of human diseases. Here, we characterized that the ribosomal protein L6 binds to and suppresses the E3 ubiquitin ligase activity of HDM2, and subsequently attenuates HDM2-mediated p53 polyubiquitination and degradation. The enhanced p53 activity further slows down cell cycle progression and leads to cell growth inhibition. Conversely, the level of p53 is dramatically decreased upon the depletion of RPL6, indicating that RPL6 is essential for p53 stabilization. We also found that RPL6 translocalizes from the nucleolus to nucleoplasm under ribosomal stress, which facilitates its binding with HDM2. The interaction of RPL6 and HDM2 drives HDM2-mediated RPL6 polyubiquitination and proteasomal degradation. Longer treatment of actinomycin D increases RPL6 ubiquitination and destabilizes RPL6, and thereby putatively attenuates p53 response until the level of L6 subsides. Therefore, RPL6 and HDM2 form an autoregulatory feedback loop to monitor the level of p53 in response to ribosomal stress. Together, our study identifies the crucial function of RPL6 in regulating HDM2-p53 pathway, which highlights the importance of RPL6 in human genetic diseases and cancers.
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Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Proteínas Ribosómicas/metabolismo , Estrés Fisiológico , Proteína p53 Supresora de Tumor/metabolismo , Animales , Línea Celular , Proliferación Celular , Humanos , Ratones , UbiquitinaciónRESUMEN
PURPOSE: This study was to evaluate the influence of mtDNA deletion on the lung cancer cells under the conditions of hypoxia or irradiation. METHOD: The treatment conditions of lung cancer cell lines with (A549) and without mtDNA (ρ0A549: obtained by inducing from A549) included 2 h of hypoxia and 4 Gy irradiation (group 1: without treatment; group 2: 2 h of hypoxia; group 3: 4 Gy irradiation; group 4: 2 h of hypoxia plus 4 Gy irradiation). The Human OneArray™ microarray was used to hybridize with the Cy5-labeled aRNA in microarray sample preparation. Differentially expressed genes (DEGs) between the lung cancer cells with and without mtDNA were identified using NOISeq package in R. Gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were performed using the online tool of DAVID. RESULT: In the KEGG pathway analysis of down-regulated DEGs, nineteen pathways were simultaneously enriched in the four groups, which were mainly metabolism- and biosynthesis-related pathways. Nine lung cancer-related pathways were enriched in group 4, and more cancer-associated DEGs, such as MYC, MAX, and E2F1 were found in group 4 than in the other groups. CONCLUSION: The mtDNA deletion could inhibit the biosynthesis and metabolism of lung cancer cells and promote the effect of hypoxia and radiation on lung cancer cells. MYC might be the key gene of the cooperation of hypoxia and radiation and MYC, MAX, and E2F1 might play roles in hypoxia- and radiation-induced cell death in lung cancer cells without mtDNA.
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Proteínas Adaptadoras Transductoras de Señales/genética , Línea Celular Tumoral/efectos de la radiación , ADN Mitocondrial/genética , Eliminación de Gen , Hipoxia , Radiación Ionizante , Ubiquitina-Proteína Ligasas/genética , Estudios de Casos y Controles , Muerte Celular/genética , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/fisiopatología , Análisis por Micromatrices , Dosis de Radiación , Valores de Referencia , Sensibilidad y EspecificidadRESUMEN
The vertical integration of a ferromagnetic monolayer and a ferroelectric monolayer into van der Waals heterostructures offers a promising route to achieve two-dimensional multiferroic semiconductors owing to the lack of intrinsic single-phase multiferroic materials in nature. In this study, we propose a VN2H2/Al2O3 van der Waals magnetoelectric multiferroic heterostructure and investigate its electronic, magnetic, and transport properties using density functional theory combined with the Boltzmann transport theory. The VN2H2 monolayer is a room-temperature ferromagnetic semiconductor with a band gap of 0.24 eV and a Curie temperature of 411 K, while the Al2O3 monolayer is a ferroelectric semiconductor with a polarization value of 0.11 C m-2. In the VN2H2/Al2O3 van der Waals heterostructures, the conversion between the metal and the semiconductor can be controlled by altering the polarization of the Al2O3 layer. The VN2H2/Al2O3 van der Waals heterostructure retains room-temperature ferromagnetism, and the reverse of polarization is accompanied with a change in the direction of the easy magnetization axis. In addition, electrostatic doping can significantly improve the conductivity of the downward polarization state and transform the upward polarization state from a metal to a half-metal, achieving 100% spin polarization. Our results thus pave the way for achieving highly tunable electromagnetic and transport properties in van der Waals magnetoelectric heterostructures, which have potential applications in next-generation low-power logic and memory devices.
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We here describe the external morphology and complete mitochondrial genome characteristics of Mecidea indica Dallas, 1851, and clarify the evolutionary rate and divergence time. The M. indica mitochondrial genome length is 15,670 bp, and it exhibits a typical high A+T-skew (76.31%). The sequence shows strong synteny with the original gene arrangement of Drosophila yakuba Burla, 1954 without rearrangement. The M. indica mitochondrial genome characteristics were analyzed, and phylogenetic trees of Pentatomidae were reconstructed using Bayesian methods based on different datasets of the mitochondrial genome datasets. Phylogenetic analysis shows that M. indica belongs to Pentaotominae and form a sister-group with Anaxilaus musgravei Gross, 1976, and Asopinae is highly supported as monophyletic. Molecular clock analysis estimates a divergence time of Pentatomidae of 122.75 Mya (95% HPD: 98.76-145.43 Mya), within the Mesozoic Cretaceous; the divergence time of M. indica and A. musgravii was no later than 50.50 Mya (95% HPD: 37.20-64.80 Mya). In addition, the divergence time of Asopinae was 62.32 Mya (95% HPD: 47.08-78.23 Mya), which was in the Paleogene of the Cenozoic era. This study is of great significance for reconstructing the phylogeny of Pentatomidae and providing insights into its evolutionary history.
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Genoma Mitocondrial , Heterópteros , Animales , Filogenia , Teorema de Bayes , Heterópteros/genética , Evolución BiológicaRESUMEN
Capsaicinoids (CPCs) is a special ingredient with pungent smell in condiments, which can also be used as an exogenetic marker for kitchen waste oil. Development of immunoassay for CPCs remains a challenging due to relatively difficult preparation of the broad-spectrum antibody (Ab). In this work, a broad-spectrum polyclonal antibody (pAb) which can simultaneously recognize capsaicin (CPC), dihydrocapsaicin (DCPC), nordihydrocapsaicin (NDCPC), and N-vanillylnonanamide (N-V) is produced, and a non-enzyme immunoassay (NISA) based on this Ab, dendritic mesoporous silica nanomaterials (DMSNs), polydopamine (PDA), and high catalytic efficiency of Pt nanoparticles to prepare signal probe (DMSNs@PDA@Pt) is established. Here, the limit of detection (LOD) of NISA for CPC is as low as 0.04 µg L-1. It is worth mentioning that the LOD of the proposed NISA is at least 23 times lower than that of traditional enzyme-linked immunosorbent assay (ELISA) based on horseradish peroxidase (HRP). Moreover, the proposed NISA is applied to detect CPCs in edible oil samples, the result has good consistency with that of ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The proposed NISA based on DMSN@PDA@Pt and broad-spectrum Ab is an ideal tool for highly effective screening CPCs for kitchen waste oil abuse surveillance.
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Indoles , Nanopartículas , Polímeros , Dióxido de Silicio , Cromatografía Liquida , Espectrometría de Masas en Tándem/métodos , Anticuerpos , Inmunoensayo/métodos , Límite de DetecciónRESUMEN
Common typical ß-agonists mainly include ractopamine (RAC), salbutamol (SAL), and clenbuterol (CLB). In view of the harm to human health causes by the ingestion of animal derived food containing ß-agonists, and a series of regulations have been issued to restrict the usage of ß-agonists as growth promoters. In this work, a fluorescence immunoassay is developed for the simultaneous detection of typical ß-agonists based on blue-green upconversion nanoparticles (UCNPs) combine with magnetic separation. Here, blue-green UCNPs act as a signal amplification source, and magnetic polystyrene microspheres (MPMs) act as an ideal separation medium. Based on a competitive form, capture probe competes (RAC-OVA@MPMs and SAL-OVA@MPMs) with targets to bind corresponding signal probe (anti-RAC antibody@NaYF4:Yb, Tm UCNPs and anti-SAL antibody@NaYF4:Yb, Er UCNPs). The fluorescence difference values of the competitive immune-complex obtained via magnetic separation at 483 nm and 550 nm are proportional to concentrations of RAC and SAL, respectively. The immunoassay has the wide detection linear range from 0.001 to 100 µg L-1, and the low limit of detection (LOD) is 5.04 × 10-4 µg L-1 for RAC, 1.97 × 10-4 µg L-1 for SAL, respectively. Meanwhile, use of antibody with same recognition ability for SAL and CLB makes that the fluorescence immunoassay can achieve simultaneous detection of three typical ß-agonists (RAC, SAL, and CLB). This fluorescence immunoassay has good application value and practicability for simultaneous detection of typical ß-agonists in animal derived food.
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Clenbuterol , Nanopartículas , Animales , Humanos , Fenetilaminas , Albuterol , InmunoensayoRESUMEN
Low temperatures significantly affect the growth and yield of peanuts. Temperatures lower than 12 °C are generally detrimental for the germination of peanuts. To date, there has been no report on precise information on the quantitative trait loci (QTL) for cold tolerance during the germination in peanuts. In this study, we developed a recombinant inbred line (RIL) population comprising 807 RILs by tolerant and sensitive parents. Phenotypic frequencies of germination rate low-temperature conditions among RIL population showed normally distributed in five environments. Then, we constructed a high density SNP-based genetic linkage map through whole genome re-sequencing (WGRS) technique and identified a major quantitative trait locus (QTL), qRGRB09, on chromosome B09. The cold tolerance-related QTLs were repeatedly detected in all five environments, and the genetic distance was 6.01 cM (46.74 cM - 61.75 cM) after taking a union set. To further confirm that qRGRB09 was located on chromosome B09, we developed Kompetitive Allele Specific PCR (KASP) markers for the corresponding QTL regions. A regional QTL mapping analysis, which was conducted after taking the intersection of QTL intervals of all environments into account, confirmed that qRGRB09 was between the KASP markers, G22096 and G220967 (chrB09:155637831-155854093), and this region was 216.26 kb in size, wherein a total of 15 annotated genes were detected. This study illustrates the relevance of WGRS-based genetic maps for QTL mapping and KASP genotyping that facilitated QTL fine mapping of peanuts. The results of our study also provided useful information on the genetic architecture underlying cold tolerance during germination in peanuts, which in turn may be useful for those engaged in molecular studies as well as crop improvement in the cold-stressed environment.
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Peanut (Arachis hypogaea L.), one of the leading oilseed crops worldwide, is an important source of vegetable oil, protein, minerals and vitamins. Peanut is widely cultivated in Asia, Africa and America, and China is the largest producer and consumer of peanut. Genetic engineering has shown great potential to alter the DNA makeup of an organism which is largely hindered by the low transformation and screening efficiency including in peanut. DsRed2 is a reporter gene widely utilized in genetic transformation to facilitate the screening of transformants, but never used in peanut genetic transformation. In this study, we have demonstrated the potential of the red fluorescence protein DsRed2 as a visual reporter to improve screening efficiency in peanut. DsRed2 was firstly expressed in protoplasts isolated from peanut cultivar Zhonhua 12 by PEG, and red fluorescence was successfully detected. Then, DsRed2 was expressed in peanut plants Zhonghua 12 driven by 35S promoter via Agrobacterium tumefaciens-mediated transformation. Red fluorescence was visually observed in calli and regenerated shoots, as well as in roots, leaves, flowers, fresh pod shells and mature seeds, suggesting that transgenic screening could be initiated at the early stage of transformation, and continued to the progeny. Upon screening with DsRed2, the positive plant rate was increased from 56.9% to 100%. The transgenic line was then used as the male parent to be crossed with Zhonghua 24, and the hybrid seeds showed red fluorescence as well, indicating that DsRed2 could be applied to hybrid plant identification very efficiently. DsRed2 was also expressed in hairy roots of Huayu 23 via Agrobacterium rhizogenes-mediated transformation, and the transgenic roots were easily selected by red fluorescence. In summary, the DsRed2 is an ideal reporter to achieve maximum screening efficiency and accuracy in peanut genetic transformation.
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Cold stress is a major environmental factor that affects plant growth and development, as well as fruit postharvest life and quality. MicroRNAs (miRNAs) are a class of non-coding small RNAs that play crucial roles in various abiotic stresses. Peanuts (Arachis hypogaea L.), one of the most important grain legumes and source of edible oils and proteins, are cultivated in the semi-arid tropical and subtropical regions of the world. To date, there has been no report on the role of miRNAs in the response to cold stress in cultivated peanuts. In this study, we profiled cold-responsive miRNAs in peanuts using deep sequencing in cold-sensitive (WQL20) alongside a tolerant variety (WQL30). A total of 407 known miRNAs and 143 novel peanut-specific miRNAs were identified. The expression of selected known and novel miRNAs was validated by northern blotting and six known cold-responsive miRNAs were revealed. Degradome sequencing identified six cold-responsive miRNAs that regulate 12 target genes. The correlative expression patterns of several miRNAs and their target genes were further validated using qRT-PCR. Our data showed that miR160-ARF, miR482-WDRL, miR2118-DR, miR396-GRF, miR162-DCL, miR1511-SRF, and miR1511-SPIRAL1 modules may mediate cold stress responses. Transient expression analysis in Nicotiana benthamiana found that miR160, miR482, and miR2118 may play positive roles, and miR396, miR162, and miR1511 play negative roles in the regulation of peanut cold tolerance. Our results provide a foundation for understanding miRNA-dependent cold stress response in peanuts. The characterized correlations between miRNAs and their response to cold stress could serve as markers in breeding programs or tools for improving cold tolerance of peanuts.
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Multiple myeloma (MM) is a hematological malignancy that results from the malignant proliferation of plasma cells in the bone marrow. B cell maturation antigen (BCMA) is highly selectively expressed in malignant plasma cells and is a novel therapeutic target for MM. Here, we developed a bispecific T cell engager, IBI379, that targets BCMA and CD3, and investigated its antitumor efficacy against MM. IBI379 showed strong binding affinity with both BCMA and CD3, which triggered T cell activation, proliferation, and cytokine release. An in vitro study demonstrated that IBI379 induced the lysis of MM cells expressing differing levels of BCMA on the cell surface. Administration of IBI379 in H929 or Daudi-BCMA cell xenograft mouse models significantly inhibited tumor growth without inducing body weight loss. The mechanism of action study revealed the accumulation of CD4+CD8+ T cells and granzyme B-positive T cells in tumors that were treated with IBI379. Moreover, administration of low dose of IBI379 in cynomolgus monkeys was well-tolerated and induced the depletion of BCMA+ B cells and a mild transient increase of cytokines. Collectively, these results demonstrate that IBI379 is a highly potent therapeutic strategy for depleting BCMA-positive B cells and is a promising approach for the treatment of MM.
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Anticuerpos Biespecíficos , Mieloma Múltiple , Animales , Anticuerpos Biespecíficos/farmacología , Anticuerpos Biespecíficos/uso terapéutico , Antígeno de Maduración de Linfocitos B/metabolismo , Complejo CD3/inmunología , Linfocitos T CD8-positivos/metabolismo , Citocinas/uso terapéutico , Humanos , Ratones , Mieloma Múltiple/tratamiento farmacológico , Mieloma Múltiple/patología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Chronic elevated free fatty (FFA) levels are linked to metabolic disorders and tumorigenesis. However, the molecular mechanism by which FFAs induce cancer remains poorly understood. Here, we show that the tumor suppressor PTEN protein levels were decreased in high fat diet (HFD) fed mice. As palmitic acid (PA, C16:0) showed a significant increase in the HFD fed mice, we further investigated its role in PTEN down regulation. Our studies revealed that exposure of cells to high doses of PA induced mTOR/S6K-mediated phosphorylation of PTEN at T366. The phosphorylation subsequently enhanced the interaction of PTEN with the E3 ubiquitin ligase WW domain-containing protein 2 (WWP2), which promoted polyubiquitination of PTEN and protein degradation. Consistent with PTEN degradation, exposure of cells to increased concentrations of PA also promoted PTEN-mediated AKT activation and cell proliferation. Significantly, a higher level of S6K activation, PTEN T366 phosphorylation, and AKT activation were also observed in the livers of the HFD fed mice. These results provide a molecular mechanism by which a HFD and elevated PA regulate cell proliferation through inactivation of tumor suppressor PTEN.
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Proliferación Celular , Neoplasias del Colon/patología , Obesidad/patología , Fosfohidrolasa PTEN/metabolismo , Ácido Palmítico/farmacología , Treonina/metabolismo , Animales , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/metabolismo , Inhibidores Enzimáticos/farmacología , Células HCT116 , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Obesidad/etiología , Obesidad/metabolismo , Fosfohidrolasa PTEN/genética , Fosforilación , Proteolisis , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Treonina/química , Treonina/genética , UbiquitinaciónRESUMEN
Corncob is an economic feedstock and more than 20 million tons of corncobs are produced annually in China. Abundant xylose can be potentially converted from the large amount of hemicellulosic materials in corncobs, which makes the crop residue an attractive alternative substrate for a value-added production of a variety of bioproducts. Lactic acid can be used as a precursor for poly-lactic acid production. Although current industrial lactic acid is produced by lactic acid bacteria using enriched medium, production by Rhizopus oryzae is preferred due to its exclusive formation of the L-isomer and a simple nutrition requirement by the fungus. Production of L-(+)-lactic acid by R. oryzae using xylose has been reported; however, its yield and conversion rate are poor compared with that of using glucose. In this study, we report an adapted R. oryzae strain HZS6 that significantly improved efficiency of substrate utilization and enhanced production of L-(+)-lactic acid from corncob hydrolysate. It increased L-(+)-lactic acid final concentration, yield, and volumetric productivity more than twofold compared with its parental strain. The optimized growth and fermentation conditions for Strain HZS6 were defined.
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Ácido Láctico/biosíntesis , Rhizopus/metabolismo , Zea mays/metabolismo , Adaptación Fisiológica , Alimentación Animal/análisis , Reactores Biológicos , Biotecnología , Celulosa/metabolismo , Fermentación , Hidrólisis , Ácido Láctico/química , Lignina/metabolismo , Estereoisomerismo , Xilosa/metabolismo , Zea mays/químicaRESUMEN
MicroRNAs (miRNAs) can function as tumor suppressor or oncogenic genes. The putative targets of miR-223 include tumor suppressor gene, RhoB. Here we sought to investigate the role of miR-223-RhoB signaling pathway in proliferation of colon cancer. We used Western blot, immunofluorescence staining, or RT-PCR to detect expression levels of miR-223 and RhoB in colon adenocarcinoma and adjacent non-cancerous tissue samples, or in human colon adenocarcinoma cell lines. MTT assay was used to determine proliferation and apoptosis in cell lines. We further used Western blot to determine levels of cell cycle regulators CDK1 and Cyclin B1 with anti-miR-223 or apoptosis with overexpression of RhoB. The expression level of miR-223 was significantly upregulated in clinical samples and cell lines of colon adenocarcinoma, in contrast to down-regulation of RhoB. In addition, we showed that inhibition of miR-223 led to upregulation of RhoB and in turn suppression of proliferation of colon adenocarcinoma. Moreover, inhibition of miR-223 or overexpression of RhoB induced cell arrest or apoptosis in colon adenocarcinoma. These results suggest that miR-223-RhoB signaling pathway plays an important role in modulation of proliferation, cell arrest, and apoptosis in colon cancer.
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Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Apoptosis , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , MicroARNs/metabolismo , Transducción de Señal , Proteína de Unión al GTP rhoB/metabolismo , Adenocarcinoma/genética , Apoptosis/genética , Secuencia de Bases , Puntos de Control del Ciclo Celular/genética , Línea Celular Tumoral , Proliferación Celular , Neoplasias del Colon/genética , Regulación hacia Abajo/genética , Femenino , Fase G2/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , MicroARNs/genética , Persona de Mediana Edad , Mitosis/genética , Regulación hacia Arriba/genéticaRESUMEN
It is of great importance for the detection of epilepsy in clinical applications. Based on the limitations of the common used approximate entropy (ApEn) in the epilepsy detection, this paper analyzes epileptic EEG signals with the sample entropy (SampEn) approach, a new method for signal analysis with much higher precision than that of the ApEn. Data analysis results show that the values from both ApEn and SampEn decrease significantly when the epilepsy is burst. Furthermore, the SampEn is more sensitive to EEG changes caused by the epilepsy, about 15%-20% higher than the results of the ApEn.
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Algoritmos , Electroencefalografía/métodos , Epilepsia/diagnóstico , Dinámicas no Lineales , Procesamiento de Señales Asistido por Computador , Interpretación Estadística de Datos , Entropía , Epilepsia/fisiopatología , HumanosRESUMEN
Dysfunctions in ribosome biogenesis cause developmental defects and increased cancer susceptibility; however, the connection between ribosome assembly and tumorigenesis remains unestablished. Here we show that hCINAP (also named AK6) is required for human 18S rRNA processing and 40S subunit assembly. Homozygous CINAP(-/-) mice show embryonic lethality. The heterozygotes are viable and show defects in 18S rRNA processing, whereas no delayed cell growth is observed. However, during rapid growth, CINAP haploinsufficiency impairs protein synthesis. Consistently, hCINAP depletion in fast-growing cancer cells inhibits ribosome assembly and abolishes tumorigenesis. These data demonstrate that hCINAP reduction is a specific rate-limiting controller during rapid growth. Notably, hCINAP is highly expressed in cancers and correlated with a worse prognosis. Genome-wide polysome profiling shows that hCINAP selectively modulates cancer-associated translatome to promote malignancy. Our results connect the role of hCINAP in ribosome assembly with tumorigenesis. Modulation of hCINAP expression may be a promising target for cancer therapy.