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1.
Prehosp Emerg Care ; : 1-13, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950135

RESUMO

Objectives: Emergency medical triage is crucial for prioritizing patient care in emergency situations, yet its effectiveness can vary significantly based on the experience and training of the personnel involved. This study aims to evaluate the efficacy of integrating Retrieval Augmented Generation (RAG) with Large Language Models (LLMs), specifically OpenAI's GPT models, to standardize triage procedures and reduce variability in emergency care.Methods: We created 100 simulated triage scenarios based on modified cases from the Japanese National Examination for Emergency Medical Technicians. These scenarios were processed by the RAG-enhanced LLMs, and the models were given patient vital signs, symptoms, and observations from emergency medical services (EMS) teams as inputs. The primary outcome was the accuracy of triage classifications, which was used to compare the performance of the RAG-enhanced LLMs to that of emergency medical technicians and emergency physicians. Secondary outcomes included the rates of under-triage and over-triage.Results: The Generative Pre-trained Transformer 3.5 (GPT-3.5) with RAG model achieved a correct triage rate of 70%, significantly outperforming Emergency Medical Technicians (EMTs) with 35% and 38% correct rates, and emergency physicians with 50% and 47% correct rates (p < 0.05). Additionally, this model demonstrated a substantial reduction in under-triage rates to 8%, compared to 33% for GPT-3.5 without RAG, and 39% for GPT-4 without RAG.Conclusions: The integration of RAG with LLMs shows promise in improving the accuracy and consistency of medical assessments in emergency settings. Further validation in diverse medical settings with broader datasets is necessary to confirm the effectiveness and adaptability of these technologies in live environments.

2.
Water Sci Technol ; 88(11): 2719-2732, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38096064

RESUMO

Various types of small-scale wastewater treatment systems are widely used in rural areas, and life-cycle assessment (LCA) should be performed to evaluate their environmental performance. In this study, septic systems were first classified into five categories based on their wastewater treatment performance. Effluent samples from actual systems were collected, and their water qualities were determined. A model to evaluate the environmental load from the septic systems using LCA methods was then established. The water-quality values obtained were input to the model, and the life-cycle environmental costs of the classified septic systems were calculated. The mean environmental load of the effluent during the operation stage was 37.6%, confirming that evaluation of an effluent discharge inventory using LCA, inspection, and water-quality monitoring to improve operations is critical for reducing the environmental load. The operation stage accounts for over 99% of the involved eutrophication, biological toxicity, and toxic chemicals, which are strongly related to the quality of the effluent. Evaluation of the effluent discharge inventory using LCA is of great significance, even for small-scale wastewater treatment systems. The set of procedures developed in this study can be used to calculate comprehensive environmental impacts at wastewater treatment plants.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias , Eliminação de Resíduos Líquidos/métodos , Água , Japão , Meio Ambiente
3.
Biosci Biotechnol Biochem ; 86(1): 68-77, 2021 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-34661636

RESUMO

We performed whole genome sequence analyses of Agreia sp. D1110 and Microbacterium trichothecenolyticum D2006 that secrete enzymes to produce cyclo-{→6)-α-d-Glcp-(1→6)-α-d-Glcp-(1→6)-α-d-Glcp-(1→6)-α-d-Glcp-(1→} (CI4) from dextran. Full-length amino acid sequences of CI4-forming enzymes were identified by matching known N-terminal amino acid sequences with products of the draft genome. Domain searches revealed that the CI4-forming enzymes are composed of Glycoside Hydrolase family 66 (GH66) domain, Carbohydrate Binding Module family 35 (CBM35) domain, and CBM13 domain, categorizing the CI4-forming enzymes in the GH66. Furthermore, the amino acid sequences of the two CI4-forming enzymes were 71% similar to each other and up to 51% similar to cycloisomaltooligosaccharide glucanotransferases (CITases) categorized in GH66. Differences in sequence between the CI4-forming enzymes and the CITases suggest mechanisms to produce specific cycloisomaltooligosaccharides, and whole genome sequence analyses identified a gene cluster whose gene products likely work in concert with the CI4-forming enzymes.


Assuntos
Microbacterium
4.
Curr Genet ; 64(6): 1245-1260, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29654355

RESUMO

The paralogous transcription factors AraR and XlnR in Aspergillus regulate genes that are involved in degradation of cellulose and hemicellulose and catabolism of pentose. AraR and XlnR target the same genes for pentose catabolism but target different genes encoding enzymes for polysaccharide degradation. To uncover the relationship between these paralogous transcription factors, we examined their contribution to regulation of the PCP genes and compared their preferred recognition sequences. Both AraR and XlnR are involved in induction of all the pentose catabolic genes in A. oryzae except larA encoding L-arabinose reductase, which was regulated by AraR but not by XlnR. DNA-binding studies revealed that the recognition sequences of AraR and XlnR also differ only slightly; AraR prefers CGGDTAAW, while XlnR prefers CGGNTAAW. All the pentose catabolic genes possess at least one recognition site to which both AraR and XlnR can bind. Cooperative binding by the factors was not observed. Instead, they competed to bind to the shared sites. XlnR bound to the recognition sites mentioned above as a monomer, but bound to the sequence TTAGSCTAA on the xylanase promoters as a dimer. Consequently, AraR and XlnR have significantly similar, but not the same, DNA-binding properties. Such a slight difference in these paralogous transcription factors may lead to complex outputs in enzyme production depending on the concentrations of coexisting inducer molecules in the natural environment.


Assuntos
Aspergillus oryzae/metabolismo , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica/fisiologia , Via de Pentose Fosfato/fisiologia , Multimerização Proteica/fisiologia , Elementos de Resposta , Transativadores/metabolismo , Aspergillus oryzae/química , Aspergillus oryzae/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Transativadores/química , Transativadores/genética
5.
Microb Cell Fact ; 17(1): 151, 2018 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-30241528

RESUMO

BACKGROUND: Genetic tools including constitutive and inducible promoters have been developed over the last few decades for strain engineering in Streptomyces. Inducible promoters are useful for controlling gene expression, however only a limited number are applicable to Streptomyces. The aim of this study is to develop a controllable protein expression system based on an inducible promoter using sugar inducer, which has not yet been widely applied in Streptomyces. RESULTS: To determine a candidate promoter, inducible protein expression was first examined in Streptomyces avermitilis MA-4680 using various carbon sources. Xylose isomerase (xylA) promoter derived from xylose (xyl) operon was selected due to strong expression of xylose isomerase (XylA) in the presence of D-xylose. Next, a xylose-inducible protein expression system was constructed by investigating heterologous protein expression (chitobiase as a model protein) driven by the xylA promoter in Streptomyces lividans. Chitobiase activity was detected at high levels in S. lividans strain harboring an expression vector with xylA promoter (pXC), under both xylose-induced and non-induced conditions. Thus, S. avermitilis xylR gene, which encodes a putative repressor of xyl operon, was introduced into constructed vectors in order to control protein expression by D-xylose. Among strains constructed in the study, XCPR strain harboring pXCPR vector exhibited strict regulation of protein expression. Chitobiase activity in the XCPR strain was observed to be 24 times higher under xylose-induced conditions than that under non-induced conditions. CONCLUSION: In this study, a strictly regulated protein expression system was developed based on a xylose-induced system. As far as we could ascertain, this is the first report of engineered inducible protein expression in Streptomyces by means of a xylose-induced system. This system might be applicable for controllable expression of toxic products or in the field of synthetic biology using Streptomyces strains.


Assuntos
Engenharia Metabólica/métodos , Streptomyces/genética , Acetilglucosaminidase/biossíntese , Aldose-Cetose Isomerases/genética , Regulação Bacteriana da Expressão Gênica , Regiões Promotoras Genéticas , Streptomyces/metabolismo
6.
Drug Metab Dispos ; 44(1): 137-50, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26534988

RESUMO

The human pregnane X receptor (hPXR) is a xenobiotic-sensing nuclear receptor that transcriptionally regulates drug metabolism-related genes. The aim of the present study was to elucidate the mechanism by which hPXR is regulated through threonine-408. A phosphomimetic mutation at threonine-408 (T408D) reduced the transcriptional activity of hPXR and its protein stability in HepG2 and SW480 cells in vitro and mouse livers in vivo. Proteasome inhibitors (calpain inhibitor I and MG132) and Hsp90 inhibitor geldanamycin, but not Hsp70 inhibitor pifithrin-µ, increased wild-type (WT) hPXR in the nucleus. The translocation of the T408D mutant to the nucleus was significantly reduced even in the presence of proteasome inhibitors, whereas the complex of yellow fluorescent protein (YFP)-hPXR T408D mutant with heat shock cognate protein 70/heat shock protein 70 and carboxy terminus Hsp70-interacting protein (CHIP; E3 ligase) was similar to that of the WT in the cytoplasm. Treatment with pifithrin-µ and transfection with anti-CHIP small-interfering RNA reduced the levels of CYP3A4 mRNA induced by rifampicin, suggesting the contribution of Hsp70 and CHIP to the transactivation of hPXR. Autophagy inhibitor 3-methyladenine accumulated YFP-hPXR T408D mutant more efficiently than the WT in the presence of proteasome inhibitor lactacystin, and the T408D mutant colocalized with the autophagy markers, microtubule-associated protein 1 light chain 3 and p62, which were contained in the autophagic cargo. Lysosomal inhibitor chloroquine caused the marked accumulation of the T408D mutant in the cytoplasm. Protein kinase C (PKC) directly phosphorylated the threonine-408 of hPXR. These results suggest that hPXR is regulated through its phosphorylation at threonine-408 by PKC, CHIP/chaperone-dependent stability check, and autophagic degradation pathway.


Assuntos
Autofagia , Hepatócitos/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Receptores de Esteroides/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Citocromo P-450 CYP3A/biossíntese , Citocromo P-450 CYP3A/genética , Indução Enzimática , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Humanos , Masculino , Camundongos Endogâmicos ICR , Mutação , Fosforilação , Receptor de Pregnano X , Complexo de Endopeptidases do Proteassoma/genética , Inibidores de Proteassoma/farmacologia , Proteína Quinase C/metabolismo , Estabilidade Proteica , Proteólise , Interferência de RNA , Receptores de Esteroides/química , Receptores de Esteroides/genética , Treonina , Fatores de Tempo , Transcrição Gênica , Transfecção , Ubiquitina-Proteína Ligases/genética
7.
Drug Metab Dispos ; 42(10): 1708-18, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25074870

RESUMO

The human pregnane X receptor (hPXR) is recognized as a xenobiotic-sensing nuclear receptor that transcriptionally regulates the gene expression of drug-metabolizing enzymes and transporters. Our study elucidates the mechanism by which the localization of hPXR is regulated through threonine-290. A phosphomimetic mutation at threonine-290 (T290D) retained hPXR in the cytoplasm of HepG2, HuH6, and SW480 cells in vitro and the mouse liver in vivo even after treatment with rifampicin, and a phosphodeficient mutation (T290A) translocated from the cytoplasm to the nucleus as the wild-type hPXR. The amount of the unphosphorylated wild-type yellow fluorescent protein-hPXR fusion protein but not the T290A mutant increased on Phos-tag gels in response to stimulations with rifampicin and cyclin-dependent kinase 2 inhibitor roscovitine, and a marked increase was observed in the unphosphorylated levels of the T290A mutant in nontreated cells. The Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) inhibitor KN93 [2-[N-(2-hydroxyethyl)]-N-(4-methoxybenzenesulfonyl)]amino-N-(4-chlorocinnamyl)-N-methylbenzylamine)] and transfection with anti-CaMKII small-interfering RNA (siRNA) enhanced the unphosphorylated levels of the wild-type protein. CaMKII directly phosphorylated the threonine-290 of hPXR, and the T290A mutant conferred resistance to CaMKII. The protein phosphatase (PP) inhibitor okadaic acid (100 nM) and transfection with anti-PP1 siRNA but not anti-PP2A siRNA led to reduced expression of CYP3A4 mRNA. After the rifampicin and roscovitine stimulations, PP1 was recruited to the wild-type hPXR but not the T290A mutant. These results suggest that phosphorylation at threonine-290 by CaMKII may impair the function of hPXR by repressing its translocation to the nucleus, and dephosphorylation by PP1 is necessary for the xenobiotic-dependent nuclear translocation of hPXR.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Núcleo Celular/metabolismo , Proteína Fosfatase 1/metabolismo , Receptores de Esteroides/química , Receptores de Esteroides/metabolismo , Treonina/metabolismo , Animais , Benzilaminas/farmacologia , Linhagem Celular , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Glucuronosiltransferase/biossíntese , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Mutação , Ácido Okadáico/farmacologia , Fosforilação/efeitos dos fármacos , Receptor de Pregnano X , Transporte Proteico , Purinas/farmacologia , RNA Interferente Pequeno/farmacologia , Rifampina/farmacologia , Roscovitina , Sulfonamidas/farmacologia , Treonina/genética
8.
Breed Sci ; 63(2): 211-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23853516

RESUMO

Strawberry is rich in anthocyanins, which are responsible for the red color, and contains several colorless phenolic compounds. Among the colorless phenolic compounds, some, such as hydroxycinammic acid derivatives, emit blue-green fluorescence when excited with ultraviolet (UV) light. Here, we investigated the effectiveness of image analyses for estimating the levels of anthocyanins and UV-excited fluorescent phenolic compounds in fruit. The fruit skin and cut surface of 12 cultivars were photographed under visible and UV light conditions; colors were evaluated based on the color components of images. The levels of anthocyanins and UV-excited fluorescent compounds in each fruit were also evaluated by spectrophotometric and high performance liquid chromatography (HPLC) analyses, respectively and relationships between these levels and the image data were investigated. Red depth of the fruits differed greatly among the cultivars and anthocyanin content was well estimated based on the color values of the cut surface images. Strong UV-excited fluorescence was observed on the cut surfaces of several cultivars, and the grayscale values of the UV-excited fluorescence images were markedly correlated with the levels of those fluorescent compounds as evaluated by HPLC analysis. These results indicate that image analyses can select promising genotypes rich in anthocyanins and fluorescent phenolic compounds.

9.
Sci Rep ; 13(1): 6771, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37186239

RESUMO

Sodium niobate (NaNbO3) is a potential material for lead-free dielectric ceramic capacitors for energy storage applications because of its antipolar ordering. In principle, a reversible phase transition between antiferroelectric (AFE) and ferroelectric (FE) phases can be induced by an application of electric field (E) and provides a large recoverable energy density. However, an irreversible phase transition from the AFE to the FE phase usually takes place and an AFE-derived polarization feature, a double polarization (P)-E hysteresis loop, does not appear. In this study, we investigate the impact of chemically induced hydrostatic pressure (pchem) on the phase stability and polarization characteristics of NaNbO3-based ceramics. We reveal that the cell volume of Ca-modified NaNbO3 [(CaxNa1-2xVx)NbO3], where V is A-site vacancy, decreases with increasing x by a positive pchem. Structural analysis using micro-X-ray diffraction measurements shows that a reversible AFE-FE phase transition leads to a double P-E hysteresis loop for the sample with x = 0.10. DFT calculations support that a positive pchem stabilizes the AFE phase even after the electrical poling and provides the reversible phase transition. Our study demonstrates that an application of positive pchem is effective in delivering the double P-E loop in the NaNbO3 system for energy storage applications.

10.
Nanomaterials (Basel) ; 12(23)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36500793

RESUMO

We investigate the origin of ferroelectricity in the BiFeO3-LaFeO3 system in rhombohedral R3c and tetragonal P4mm symmetries by ab initio density functional theory calculations and compare their electronic features with paraelectric orthorhombic Pnma symmetry. We show that a coherent accommodation of stereo-active lone pair electrons of Bi is the detrimental factor of ferroelectricity. A Bloch function arising from an indirect Bi_6p-Fe_3d hybridization mediated through O_2p is the primary origin of spontaneous polarization (Ps) in the rhombohedral system. In the orthorhombic system, a similar Bloch function was found, whereas a staggered accommodation of stereo-active lone pair electrons of Bi exclusively results in paraelectricity. A giant Ps reported in the tetragonal system originates from an orbital hybridization of Bi_6p and O_2p, where Fe-3d plays a minor role. The Ps in the rhombohedral system decreases with increasing La content, while that in the tetragonal system displays a discontinuous drop at a certain La content. We discuss the electronic factors affecting the Ps evolutions with La content.

11.
Biosci Biotechnol Biochem ; 75(5): 953-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21597200

RESUMO

XlnR is a transcription factor that mediates D-xylose-triggered induction of xylanolytic and cellulolytic genes in Aspergillus. In order to clarify the molecular mechanisms underlying XlnR-mediated induction, Aspergillus oryzae XlnR was fused with the c-myc tag and examined by Western blotting. Phosphate-affinity SDS-PAGE revealed that XlnR was present as a mixture of variously phosphorylated forms in the absence of D-xylose, and that D-xylose triggered additional phosphorylation of the protein. D-Xylose-triggered phosphorylation was a rapid process occurring within 5 min prior to the accumulation of xynG2 mRNA, and removal of D-xylose caused slow dephosphorylation, leading to less-phosphorylated forms. At 30 min after removal, the phosphorylation status was almost identical to that in the absence of D-xylose, and the level of xynG2 mRNA started to decrease. These results indicate that XlnR is highly phosphorylated when it is active in transactivation, implying that D-xylose-triggered reversible phosphorylation controls XlnR activity.


Assuntos
Aspergillus oryzae/genética , Celulose/metabolismo , Proteínas Fúngicas/metabolismo , Transativadores/metabolismo , Ativação Transcricional , Xilanos/metabolismo , Xilose/farmacologia , Aspergillus oryzae/efeitos dos fármacos , Aspergillus oryzae/metabolismo , Proteínas Fúngicas/genética , Glucose/farmacologia , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/genética , Álcoois Açúcares/farmacologia , Transativadores/genética , Transcrição Gênica/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos
13.
Nanomaterials (Basel) ; 11(7)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34361243

RESUMO

Superlattice-structured epitaxial thin films composed of Mn(5%)-doped BiFeO3 and BaTiO3 with a total thickness of 600 perovskite (ABO3) unit cells were grown on single-crystal SrTiO3 substrates by pulsed laser deposition, and their polarization and dielectric properties were investigated. When the layers of Mn-BiFeO3 and BaTiO3 have over 25 ABO3 unit cells (N), the superlattice can be regarded as a simple series connection of their individual capacitors. The superlattices with an N of 5 or less behave as a unified ferroelectric, where the BaTiO3 and Mn-BiFeO3 layers are structurally and electronically coupled. Density functional theory calculations can explain the behavior of spontaneous polarization for the superlattices in this thin regime. We propose that a superlattice formation comprising two types of perovskite layers with different crystal symmetries opens a path to novel ferroelectrics that cannot be obtained in a solid solution system.

14.
Front Plant Sci ; 12: 645111, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33747025

RESUMO

Cultivated strawberry is the most widely consumed fruit crop in the world, and therefore, many breeding programs are underway to improve its agronomic traits such as fruit quality. Strawberry cultivars were vegetatively propagated through runners and carried a high risk of infection with viruses and insects. To solve this problem, the development of F1 hybrid seeds has been proposed as an alternative breeding strategy in strawberry. In this study, we conducted a potential assessment of genomic selection (GS) in strawberry F1 hybrid breeding. A total of 105 inbred lines were developed as candidate parents of strawberry F1 hybrids. In addition, 275 parental combinations were randomly selected from the 105 inbred lines and crossed to develop test F1 hybrids for GS model training. These populations were phenotyped for petiole length, leaf area, Brix, fruit hardness, and pericarp color. Whole-genome shotgun sequencing of the 105 inbred lines detected 20,811 single nucleotide polymorphism sites that were provided for subsequent GS analyses. In a GS model construction, inclusion of dominant effects showed a slight advantage in GS accuracy. In the across population prediction analysis, GS models using the inbred lines showed predictability for the test F1 hybrids and vice versa, except for Brix. Finally, the GS models were used for phenotype prediction of 5,460 possible F1 hybrids from 105 inbred lines to select F1 hybrids with high fruit hardness or high pericarp color. These F1 hybrids were developed and phenotyped to evaluate the efficacy of the GS. As expected, F1 hybrids that were predicted to have high fruit hardness or high pericarp color expressed higher observed phenotypic values than the F1 hybrids that were selected for other objectives. Through the analyses in this study, we demonstrated that GS can be applied for strawberry F1 hybrid breeding.

15.
Sci Rep ; 11(1): 16673, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34404826

RESUMO

This study aimed to perform a comparative analysis of postoperative results between lumbar degenerative spondylolisthesis (LDS) treated with oblique lateral interbody fusion (OLIF) and transforaminal lumbar interbody fusion (TLIF) from the Chiba spine surgery registry database. Sixty-five patients who underwent single-level OLIF (O group) for LDS with ≥ 3 years' follow-up were retrospectively reviewed. The control group comprised 78 patients who underwent single-level TLIF (T group). The analyzed variables included global alignment, radiological parameters of fused segments, asymptomatic and symptomatic ASD incidence, clinical outcomes at 3 years postoperatively using the Japanese Orthopedic Association Back Pain Evaluation Questionnaire data, visual analogue scale scores for low back pain, lower extremity pain, and lower extremity numbness. There was no significant change in global alignment between the two groups. The rate of improvement in anterior intervertebral disc height was not significantly different between the groups at 1-month postoperatively. However, at the final evaluation, the anterior intervertebral disc height and incidence of asymptomatic ASD were significantly higher in the O group. There was no significant difference in symptomatic ASD, reoperation cases, or clinical results between groups. Thus, single-level OLIF can maintain the corrected disc height, but as it has no effect on global alignment, its benefit is limited.


Assuntos
Vértebras Lombares/cirurgia , Espondilolistese/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Estudos Retrospectivos , Fusão Vertebral/métodos , Resultado do Tratamento
16.
Transgenic Res ; 19(2): 211-20, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19557540

RESUMO

Lettuce big-vein disease is caused by Mirafiori lettuce virus (MiLV), which is vectored by the soil-borne fungus Olpidium brassicae. A MiLV-resistant transgenic lettuce line was developed through introducing inverted repeats of the MiLV coat protein (CP) gene. Here, a detailed characterization study of this lettuce line was conducted by comparing it with the parental, non-transformed 'Kaiser' cultivar. There were no significant differences between transgenic and non-transgenic lettuce in terms of pollen fertility, pollen dispersal, seed production, seed dispersal, dormancy, germination, growth of seedlings under low or high temperature, chromatographic patterns of leaf extracts, or effects of lettuce on the growth of broccoli or soil microflora. A significant difference in pollen size was noted, but the difference was small. The length of the cotyledons of the transgenic lettuce was shorter than that of 'Kaiser,' but there were no differences in other morphological characteristics. Agrobacterium tumefaciens used for the production of transgenic lettuce was not detected in transgenic seeds. The transgenic T(3), T(4), and T(5) generations showed higher resistance to MiLV and big-vein symptoms expression than the resistant 'Pacific' cultivar, indicating that high resistance to lettuce big-vein disease is stably inherited. PCR analysis showed that segregation of the CP gene was nearly 3:1 in the T(1) and T(2) generations, and that the transgenic T(3) generation was homozygous for the CP gene. Segregation of the neomycin phosphotransferase II (npt II) gene was about 3:1 in the T(1) generation, but the full length npt II gene was not detected in the T(2) or T(3) generation. The segregation pattern of the CP and npt II genes in the T(1) generation showed the expected 9:3:3:1 ratio. These results suggest that the fragment including the CP gene and that including the npt II gene have been integrated into two unlinked loci, and that the T(1) plant selected in our study did not have the npt II gene. DNA sequences flanking T-DNA insertions in the T(2) generation were determined using inverse PCR, and showed that the right side of the T-DNA including the npt II gene had been truncated in the transgenic lettuce.


Assuntos
Lactuca , Vírus de Plantas/patogenicidade , Plantas Geneticamente Modificadas/virologia , Vírus de RNA/patogenicidade , Agrobacterium tumefaciens/genética , Sequência de Bases , Proteínas do Capsídeo/genética , DNA Bacteriano/genética , Lactuca/genética , Lactuca/crescimento & desenvolvimento , Lactuca/virologia , Dados de Sequência Molecular , Doenças das Plantas/virologia , Vírus de Plantas/classificação , Vírus de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Vírus de RNA/classificação , Vírus de RNA/genética , Análise de Sequência de DNA , Microbiologia do Solo , Transgenes/genética
18.
J Phys Condens Matter ; 33(3)2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-32927450

RESUMO

The determination of local atomic structure at nanoscale for inhomogeneous systems is challenging. The local arrangement of atoms needs to be studied to understand the local or short-range order structures for disordered materials with a lack of long-range order periodicity. Pair distribution function (PDF) analysis is a technique, that is used to study the short-range order structure of materials: this technique is based on the evaluation of local atomic arrangement using synchrotron and neutron sources. An attempt was made to determine the local arrangement at 20 nm-scale for a typical relaxor ferroelectric material, Pb(Mg1/3Nb2/3)O3(PMN). The PDF technique was employed owing to the limited structural coherence in this disordered material. It was determined that there are three types of structures depending on the distance. A glass-like network structure was observed as a short-range order structure owing to the large off-center shift of lead atoms. With an increase in distance, the structure of PMN changed from rhombohedral to cubic. Using the above-mentioned approach, we elucidated the process of local structure averaging.

19.
Nat Commun ; 11(1): 966, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32075971

RESUMO

Titanium oxide materials have multiple functions such as photocatalytic and photovoltaic effects. Ferroelectrics provide access to light energy conversion that delivers above-bandgap voltages arising from spatial inversion symmetry breaking, whereas their wide bandgap leads to poor absorption of visible light. Bandgap narrowing offers a potential solution, but this material modification suppresses spontaneous polarization and, hence, sacrifices photovoltages. Here, we report successive-redox mediated ferrophotovoltaics that exhibit a robust visible-light response. Our single-crystal experiments and ab initio calculations, along with photo-luminescence analysis, demonstrate that divalent Fe2+ and trivalent Fe3+ coexisted in a prototypical ferroelectric barium titanate BaTiO3 introduce donor and acceptor levels, respectively, and that two sequential Fe3+/Fe2+ redox reactions enhance the photogenerated power not only under visible light but also at photon energies greater than the bandgap. Our approach opens a promising route to the visible-light activation of photovoltaics and, potentially, of photocatalysts.

20.
Appl Microbiol Biotechnol ; 85(1): 141-54, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19777228

RESUMO

XlnR is a Zn(II)2Cys6 transcriptional activator of xylanolytic and cellulolytic genes in Aspergillus. Overexpression of the aoxlnR gene in Aspergillus oryzae (A. oryzae xlnR gene) resulted in elevated xylanolytic and cellulolytic activities in the culture supernatant, in which nearly 40 secreted proteins were detected by two-dimensional electrophoresis. DNA microarray analysis to identify the transcriptional targets of AoXlnR led to the identification of 75 genes that showed more than fivefold increase in their expression in the AoXlnR overproducer than in the disruptant. Of these, 32 genes were predicted to encode a glycoside hydrolase, highlighting the biotechnological importance of AoXlnR in biomass degradation. The 75 genes included the genes previously identified as AoXlnR targets (xynF1, xynF3, xynG2, xylA, celA, celB, celC, and celD). Thirty-six genes were predicted to be extracellular, which was consistent with the number of proteins secreted, and 61 genes possessed putative XlnR-binding sites (5'-GGCTAA-3', 5'-GGCTAG-3', and 5'-GGCTGA-3') in their promoter regions. Functional annotation of the genes revealed that AoXlnR regulated the expression of hydrolytic genes for degradation of beta-1,4-xylan, arabinoxylan, cellulose, and xyloglucan and of catabolic genes for the conversion of D-xylose to xylulose-5-phosphate. In addition, genes encoding glucose-6-phosphate 1-dehydrogenase and L-arabinitol-4- dehydrogenase involved in D-glucose and L-arabinose catabolism also appeared to be targets of AoXlnR.


Assuntos
Aspergillus oryzae/fisiologia , Proteínas Fúngicas/biossíntese , Regulação Fúngica da Expressão Gênica , Regulon , Transativadores/fisiologia , Aspergillus oryzae/genética , Sítios de Ligação , Celulose/metabolismo , Biologia Computacional/métodos , DNA Fúngico/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/fisiologia , Perfilação da Expressão Gênica , Glucanos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Pentosefosfatos/metabolismo , Regiões Promotoras Genéticas , Análise de Sequência , Xilanos/metabolismo , Xilose/metabolismo
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