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1.
Int J Clin Pract ; 2023: 1489905, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37497125

RESUMO

Objective: In this study, we aimed to explore the efficacy of the autologous platelet-rich plasma (PRP) interventional circulatory perfusion combined with radiofrequency ablation and thermocoagulation (RFAT) in the treatment of discogenic low back pain (DLBP). Methods: From January 2020 to November 2022, 158 patients of the Second Affiliated Hospital of Nanchang University were selected as the study subjects, and 24 patients met the exclusion criteria. The 134 patients who met the inclusion criteria were divided into 65 patients in the control group (3 patients lost to follow-up) and 69 patients in the observation group (5 patients lost to follow-up), so 126 patients were actually completed the study, including 62 patients in the control group and 64 patients in the observation group. The control group responsible disc received RFAT, and an interventional circulatory perfusion was performed; the observation group received RFAT, and an interventional circulatory perfusion was performed, and then autologous PRP 2 ml was injected. Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) were performed before and 4 and 8 weeks after treatment, and the efficacy was evaluated at 4 and 8 weeks after treatment. The changes of lumbar disc MRI before and after treatment were observed. Results: The differences in the Visual Analog Scale (VAS) scores and the Oswestry Disability Index (ODI) between the observation group and the control group before the treatment were not statistically significant (P > 0.05 in both). However, four weeks and eight weeks after the treatment, the VAS scores and the ODIs were significantly lower in both groups than those before the treatment (P < 0.05 in both). In terms of the therapeutic efficacy, eight weeks after the treatment, the total effective rates in the control group and the observation group were 67.7% and 87.5%, respectively, with the observation group being superior to the control group (P < 0.05). Conclusion: After RFAT, interventional circulatory perfusion combined with autologous PRP intramedullary injection in the lumbar disc is a safe and effective treatment for DLBP, and it had superior long-term effects in improving the clinical symptoms and patient dysfunction than the RFAT and interventional circulatory perfusion.


Assuntos
Dor Lombar , Plasma Rico em Plaquetas , Ablação por Radiofrequência , Humanos , Dor Lombar/terapia , Resultado do Tratamento , Eletrocoagulação , Perfusão , Vértebras Lombares/cirurgia
2.
BMC Gastroenterol ; 22(1): 77, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35193513

RESUMO

BACKGROUND: Hepatocellular carcinoma (HCC) was frequently considered as a kind of malignant tumor with a poor prognosis. Cyclin-dependent kinases (CDK) 4 was considered to be cell-cycle-related CDK gene. In this study, we explored the clinical significance of CDK4 in HCC patients. METHODS: Data of HCC patients were obtained from The Cancer Genome Atlas database (TCGA) and the Gene Expression Omnibus (GEO) database. Kaplan-Meier analysis and Cox regression model were performed to calculate median survival time (MST) and the hazard ration (HR), respectively. The joint-effect analysis and prognostic risk score model were constructed to demonstrate significance of prognosis-related genes. The differential expression of prognostic genes was further validated using reverse transcription-quantitative PCR (RT-qPCR) of 58 pairs of HCC samples. RESULTS: CDK1 and CDK4 were considered prognostic genes in TCGA and GSE14520 cohort. The result of joint-effect model indicated patients in CDK1 and CDK4 low expression groups had a better prognosis in TCGA (adjusted HR = 0.491; adjusted P = 0.003) and GSE14520 cohort (adjusted HR = 0.431; adjusted P = 0.002). Regarding Kaplan-Meier analysis, high expression of CDK1 and CDK4 was related to poor prognosis in both the TCGA (P < 0.001 and = 0.001 for CDK1 and CDK4, respectively) and the GSE14520 cohort (P = 0.006 and = 0.033 for CDK1 and CDK4, respectively). However, only CDK4 (P = 0.042) was validated in RT-qPCR experiment, while CDK1 (P = 0.075) was not. CONCLUSION: HCC patients with high CDK4 expression have poor prognosis, and CDK4 could be a potential candidate diagnostic biomarker for HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/patologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/patologia , Prognóstico
3.
Nano Lett ; 19(8): 4897-4903, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-30973231

RESUMO

Creation of functional patterns in two-dimensional (2D) materials provides opportunities to extend their potential for applications. Transition-metal dichalcogenides (TMDCs) are suitable 2D materials for pattern generation because of properties including alterable polymorphic phases, easy chalcogen-vacancy formation, metal-atom insertion, and alloying. Such patterning can be used for selective functionalization. Here we report the spontaneous formation of long-range, well-ordered 1D patterns in monolayer vanadium diselenide (VSe2) by a single annealing stage during growth. Atomic-resolution images in real space combined with density-functional-theory (DFT) calculations reveal the 1D features of patterned VSe2. Further experimental characterization of the intermediate states in the growth process confirm the spontaneous formation of the 1D pattern by annealing-induced Se-deficient linear defects. The 1D pattern can be reversibly transformed to homogenous VSe2 monolayer by reintroducing Se atoms. Moreover, additional experiments demonstrate that a dispersive deposition of Pt atoms along the 1D structures of patterned VSe2 is achieved, while DFT calculations find that their catalytic activity for hydrogen evolution reaction (HER) is as good as that of Pt surfaces. The formation of long-range, well-ordered 1D patterns not only demonstrates an effective way of dimension modulation in 2D materials but also enriches the potential of intrinsically patterned 2D materials for promising catalytic activities.

4.
Nano Lett ; 19(9): 6323-6329, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31431010

RESUMO

Two-dimensional topological materials have attracted intense research efforts owing to their promise in applications for low-energy, high-efficiency quantum computations. Group-VA elemental thin films with strong spin-orbit coupling have been predicted to host topologically nontrivial states as excellent two-dimensional topological materials. Herein, we experimentally demonstrated for the first time that the epitaxially grown high-quality antimonene monolayer islands with buckled configurations exhibit significantly robust one-dimensional topological edge states above the Fermi level. We further demonstrated that these topologically nontrivial edge states arise from a single p-orbital manifold as a general consequence of atomic spin-orbit coupling. Thus, our findings establish monolayer antimonene as a new class of topological monolayer materials hosting the topological edge states for future low-power electronic nanodevices and quantum computations.

5.
Nano Lett ; 18(3): 2133-2139, 2018 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-29457727

RESUMO

Group-V elemental monolayers were recently predicted to exhibit exotic physical properties such as nontrivial topological properties, or a quantum anomalous Hall effect, which would make them very suitable for applications in next-generation electronic devices. The free-standing group-V monolayer materials usually have a buckled honeycomb form, in contrast with the flat graphene monolayer. Here, we report epitaxial growth of atomically thin flat honeycomb monolayer of group-V element antimony on a Ag(111) substrate. Combined study of experiments and theoretical calculations verify the formation of a uniform and single-crystalline antimonene monolayer without atomic wrinkles, as a new honeycomb analogue of graphene monolayer. Directional bonding between adjacent Sb atoms and weak antimonene-substrate interaction are confirmed. The realization and investigation of flat antimonene honeycombs extends the scope of two-dimensional atomically-thick structures and provides a promising way to tune topological properties for future technological applications.

6.
Chem Pharm Bull (Tokyo) ; 66(1): 96-100, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29118309

RESUMO

Cyprotuoside C (1) and cyprotuoside D (2), two new cycloartane glycosides were isolated from the ethanol extract of the rhizomes of Cyperus rotundus. Their structures were identified as 24R-9,10-seco-cycloartan-1(10),9(11)-dien-3ß,7ß,24,25-tetraol 3-O-ß-D-xylopyranosyl-(1→4)-[α-L-arabinopyranosyl-(1→6)]-ß-D-glucopyranosyl-25-O-ß-D-glucuronide (1) and 9,10-seco-cycloartan-1(10),9(11),23(24)-trien-3ß,7ß,25-triol 3-O-ß-D-xylopyranosyl-(1→4)-{α-L-arabinopyranosyl-(1→6)-[α-L-rhamnopyranosyl-(1→2)]}-ß-D-glucopyranosyl-25-O-ß-D-glucuronide (2) by spectroscopic methods.


Assuntos
Cyperus/química , Rizoma/química , Triterpenos/isolamento & purificação , Glicosídeos , Conformação Molecular , Triterpenos/química
7.
Org Biomol Chem ; 15(12): 2562-2568, 2017 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-28266679

RESUMO

The synthesis of optically pure secondary epoxy alcohols from racemic allylic alcohols using a single whole-cell biocatalyst of recombinant Escherichia coli coexpressing three oxidoreductases is described. The cascade involves the concurrent action of a styrene monooxygenase that catalyzes the formation of the chiral epoxy group, and two alcohol dehydrogenases that fulfil the epimerisation of the hydroxy group. Two sets of alcohol dehydrogenases were each applied to couple with styrene monooxygenase in order to realize the epimerisation in a stereo-complementary manner. Excellent enantio- and diastereo-selectivities were achieved for most of the 12 substrates.

8.
Appl Microbiol Biotechnol ; 101(5): 1945-1952, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27830294

RESUMO

(1S)-2-chloro-1-(3, 4-difluorophenyl) ethanol ((S)-CFPL) is an intermediate for the drug ticagrelor, and is manufactured via chemical approaches. To develop a biocatalytic solution to (S)-CFPL, an inventory of ketoreductases from Chryseobacterium sp. CA49 were rescreened, and ChKRED20 was found to catalyze the reduction of the ketone precursor with excellent stereoselectivity (>99 % ee). After screening an error-prone PCR library of the wild-type ChKRED20, two mutants, each bearing a single amino acid substitution of H145L or L205M, were identified with significantly increased activity. Then, the two critical positions were each randomized by constructing saturation mutagenesis libraries, which delivered several mutants with further enhanced activity. Among them, the mutant L205A was the best performer with a specific activity of 178 µmol/min/mg, ten times of that of the wild-type. Its k cat/K m increased by 15 times and half-life at 50 °C increased by 70 %. The mutant catalyzed the complete conversion of 150 and 200 g/l substrate within 6 and 20 h, respectively, to yield enantiopure (S)-CFPL with an isolated yield of 95 %.


Assuntos
Adenosina/análogos & derivados , Chryseobacterium/enzimologia , Etanol/análogos & derivados , Etanol/síntese química , Cetonas/metabolismo , Oxirredutases/metabolismo , 2-Propanol/química , Adenosina/síntese química , Adenosina/química , Biocatálise , Chryseobacterium/metabolismo , Etanol/química , Biblioteca Gênica , Mutagênese , NAD/química , Oxirredução , Oxirredutases/genética , Especificidade por Substrato , Ticagrelor
9.
Appl Microbiol Biotechnol ; 101(23-24): 8395-8404, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29067484

RESUMO

ChKRED20 is an efficient and robust anti-Prelog ketoreductase that can catalyze the reduction of ketones to chiral alcohols as pharmaceutical intermediates with great industrial potential. To overcome its limitation on the bioreduction of ortho-substituted acetophenone derivatives, the X-ray crystal structure of the apo-enzyme of ChKRED20 was determined at a resolution of 1.85 Å and applied to the molecular modeling and reshaping of the catalytic cavity via three rounds of iterative saturation mutagenesis together with alanine scanning and recombination. The mutant Mut3B was achieved with expanded catalytic scope that covered all the nine substrates tested as compared with two substrates for the wild type. It exhibited 13-20-fold elevated k cat/K m values relative to the wild type or to the first gain-of-activity mutant, while retaining excellent stereoselectivity toward seven of the substrates (98-> 99% ee). Another mutant 29G10 displayed complementary selectivity for eight of the ortho-substituted acetophenone derivatives, with six of them delivering excellent stereoselectivity (90-99% ee). Its k cat/K m value toward 1-(2-fluorophenyl)ethanone was 5.6-fold of the wild type. The application of Mut3B in elevated substrate concentrations of 50-100 g/l was demonstrated in 50-ml reactions, achieving 75-> 99% conversion and > 99% ee.


Assuntos
Chryseobacterium/enzimologia , Cetonas/metabolismo , Mutagênese , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Oxirredutases/genética , Oxirredutases/metabolismo , Cristalografia por Raios X , Cinética , Modelos Moleculares , Proteínas Mutantes/química , Oxirredutases/química , Conformação Proteica , Especificidade por Substrato
10.
Chemistry ; 22(39): 14048-14055, 2016 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-27514844

RESUMO

A series of novel α-diamine nickel complexes, (ArNH-C(Me)-(Me)C-NHAr)NiBr2 , 1: Ar=2,6-diisopropylphenyl, 2: Ar=2,6-dimethylphenyl, 3: Ar=phenyl), have been synthesized and characterized. X-ray crystallographic analysis showed that the coordination geometry of the α-diamine nickel complexes is markedly different from conventional α-diimine nickel complexes, and that the chelate ring (N-C-C-N-Ni) of the α-diamine nickel complex is significantly distorted. The α-diamine nickel catalysts also display different steric effects on ethylene polymerization in comparison to the α-diimine nickel catalyst. Increasing the steric hindrance of the α-diamine ligand by substitution of the o-methyl groups with o-isopropyl groups leads to decreased polymerization activity and molecular weight; however, catalyst thermal stability is significantly enhanced. Living polymerizations of ethylene can be successfully achieved using 1/Et2 AlCl at 35 °C or 2/Et2 AlCl at 0 °C. The bulky α-diamine nickel catalyst 1 with isopropyl substituents can additionally be used to control the branching topology of the obtained polyethylene at the same level of branching density by tuning the reaction temperature and ethylene pressure.

11.
Appl Microbiol Biotechnol ; 100(8): 3567-75, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26658823

RESUMO

Ethyl (S)-4-chloro-3-hydroxybutanoate ((S)-CHBE) is an important chiral intermediate for the synthesis of "blockbuster" drug statins. The carbonyl reductase ChKRED20 from Chryseobacterium sp. CA49 was found to catalyze the bio-reductive production of (S)-CHBE with excellent stereoselectivity (>99.5 % ee). Perceiving a capacity for improvement, we sought to increase the thermostability of ChKRED20 to allow a higher reaction temperature. After one round of error-prone PCR (epPCR) library screening followed by the combination of beneficial mutations, a triple-mutant MC135 was successfully achieved with substantially enhanced thermostablity. The activity of MC135 at 50 °C was similar to the wild type. However, at its temperature optima of 65 °C, the mutant displayed 63 % increase of activity compared to the wild type and remained >95 % activity after being incubated for 15 days, while the wild type had a half-life of 11.9 min at 65 °C. At a substrate/catalyst ratio of 100 (w/w), the mutant catalyzed the complete conversion of 300 g/l substrate within 1 h to yield enantiopure (S)-CHBE with an isolated yield of 95 %, corresponding to a space-time yield of 1824 mM/h.


Assuntos
Acetoacetatos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Chryseobacterium/enzimologia , Oxirredutases/genética , Oxirredutases/metabolismo , Acetoacetatos/química , Biocatálise , Chryseobacterium/química , Chryseobacterium/genética , Estabilidade Enzimática , Temperatura Alta , Isomerismo , Cinética , Mutação , Oxirredutases/química
12.
Chem Pharm Bull (Tokyo) ; 64(11): 1641-1646, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27523640

RESUMO

Six polyphenolic acids (1-6), including the three new compounds citriodolic acids A, B, and C (1-3), were isolated from the leaves of Eucalyptus citriodora. Their structures were elucidated by spectroscopic methods including one dimensional (1D)- and 2D-NMR, high-resolution electrospray ionization (HR-ESI)-MS, and circular dichroism (CD). The potential antivirus activity against respiratory syncytial virus (RSV) of all the isolated compounds was evaluated.


Assuntos
Antivirais/farmacologia , Ácidos Cafeicos/farmacologia , Dioxanos/farmacologia , Eucalyptus/química , Folhas de Planta/química , Polifenóis/farmacologia , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Antivirais/química , Antivirais/isolamento & purificação , Ácidos Cafeicos/química , Ácidos Cafeicos/isolamento & purificação , Dioxanos/química , Dioxanos/isolamento & purificação , Relação Dose-Resposta a Droga , Testes de Sensibilidade Microbiana , Conformação Molecular , Polifenóis/química , Polifenóis/isolamento & purificação , Relação Estrutura-Atividade
13.
Chem Pharm Bull (Tokyo) ; 64(1): 73-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26726748

RESUMO

Based on bioactive screening results, two new iridoid glycosides, named rotunduside G (1) and rotunduside H (2), were isolated from the rhizomes of Cyperus rotundus, together with four known ones, negundoside (3), nishindaside (4), isooleuropein (5) and neonuezhenide (6). Their structures were elucidated on the basis of spectroscopic methods and from literature values. In mice models of despair, 1 and 2 showed significant antidepressant activity.


Assuntos
Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Cyperus/química , Glicosídeos Iridoides/farmacologia , Atividade Motora/efeitos dos fármacos , Animais , Antidepressivos/química , Antidepressivos/isolamento & purificação , Elevação dos Membros Posteriores , Glicosídeos Iridoides/química , Glicosídeos Iridoides/isolamento & purificação , Masculino , Camundongos , Estrutura Molecular , Natação
14.
J Asian Nat Prod Res ; 18(7): 662-8, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26978535

RESUMO

Two new cycloartane glycosides, cyprotusides A (1) and B (2), were isolated from the rhizomes of Cyperus rotundus. Their chemical structures were elucidated on the basis of IR, MS, NMR spectroscopic analyses coupled with chemical degradation. The potential antidepressant activity of the two compounds was evaluated. In the despair mice models, compounds 1 and 2 showed significant antidepressant activity.


Assuntos
Antidepressivos/isolamento & purificação , Antidepressivos/farmacologia , Cyperus/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Rizoma/química , Triterpenos/isolamento & purificação , Triterpenos/farmacologia , Animais , Antidepressivos/química , Medicamentos de Ervas Chinesas/química , Glicosídeos/química , Camundongos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Triterpenos/química
15.
Org Biomol Chem ; 13(7): 2146-52, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25531755

RESUMO

Styrene monooxygenase (SMO) can catalyze the kinetic resolution of secondary allylic alcohols to provide enantiopure glycidol derivatives. To overcome the low theoretical yield of kinetic resolution, we designed a one-pot two-step enzymatic cascade using prochiral α,ß-unsaturated ketones as the substrates. An S-specific ketoreductase ChKRED03 was screened for the efficient bioreduction of the substrates to provide (S)-allylic alcohols, which underwent SMO-catalyzed epoxidation to achieve glycidol derivatives with contiguous stereogenic centers. Excellent enantioselectivity (ee > 99%) and diastereoselectivity (de > 99%) were achieved for the majority of the substrates, and product yields reached up to >99%.


Assuntos
Oxirredutases do Álcool/metabolismo , Compostos de Epóxi/metabolismo , Oxigenases/metabolismo , Propanóis/metabolismo , Biocatálise , Compostos de Epóxi/química , Cinética , Propanóis/química , Estereoisomerismo
16.
Environ Sci Technol ; 48(16): 9236-45, 2014 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-25072510

RESUMO

Biogenic organosulfates (OSs) are important markers of secondary organic aerosol (SOA) formation involving cross reactions of biogenic precursors (terpenoids) with anthropogenic pollutants. Until now, there has been rare information about biogenic OSs in the air of highly polluted areas. In this study, fine particle (PM2.5) samples were separately collected in daytime and nighttime from summer to fall 2010 at a site in the central Pearl River Delta (PRD), South China. Pinene-derived nitrooxy-organosulfates (pNOSs) and isoprene-derived OSs (iOSs) were quantified using a liquid chromatograph (LC) coupled with a tandem mass spectrometer (MS/MS) operated in negative electrospray ionization (ESI) mode. The pNOSs with MW 295 exhibited higher levels in fall (151 ± 86.9 ng m(-3)) than summer (52.4 ± 34.0 ng m(-3)), probably owing to the elevated levels of NOx and sulfate in fall when air masses mainly passed through city clusters in the PRD and biomass burning was enhanced. In contrast to observations elsewhere where higher levels occurred at nighttime, pNOS levels in the PRD were higher during the daytime in both seasons, indicating that pNOS formation was likely driven by photochemistry over the PRD. This conclusion is supported by several lines of evidence: the specific pNOS which could be formed through both daytime photochemistry and nighttime NO3 chemistry exhibited no day-night variation in abundance relative to other pNOS isomers; the production of the hydroxynitrate that is the key precursor for this specific pNOS was found to be significant through photochemistry but negligible through NO3 chemistry based on the mechanisms in the Master Chemical Mechanism (MCM). For iOSs, 2-methyltetrol sulfate ester which could be formed from isoprene-derived epoxydiols (IEPOX) under low-NOx conditions showed low concentrations (below the detection limit to 2.09 ng m(-3)), largely due to the depression of IEPOX formation by the high NOx levels over the PRD.


Assuntos
Butadienos/química , Hemiterpenos/química , Monoterpenos/química , Pentanos/química , Sulfatos/análise , China , Rios , Estações do Ano , Sulfatos/química , Espectrometria de Massas em Tandem
17.
Appl Microbiol Biotechnol ; 98(2): 705-15, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23644746

RESUMO

A putative enoate reductase, Achr-OYE4, was mined from the genome of Achromobacter sp. JA81, expressed in Escherichia coli, and was characterized. Sequence analysis and spectral properties indicated that Achr-OYE4 is a typical flavin mononucleotide-dependent protein; it preferred NADH over NADPH as a cofactor. The heterologously expressed protein displayed good activity and excellent stereoselectivity toward some activated alkenes in the presence of NADH, NADPH, or their recycling systems. The glucose dehydrogenase-based recycling system yielded the best results in most cases, with a product yield of up to 99 % and enantiopurity of >99 % ee. Achr-OYE4 is an important addition to the asymmetric reduction reservoir as an "old yellow enzyme" from Achromobacter.


Assuntos
Achromobacter/enzimologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/metabolismo , Achromobacter/genética , Sequência de Aminoácidos , Clonagem Molecular , Coenzimas/metabolismo , Estabilidade Enzimática , Escherichia coli/genética , Flavoproteínas/química , Flavoproteínas/genética , Flavoproteínas/isolamento & purificação , Flavoproteínas/metabolismo , Expressão Gênica , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , NAD/metabolismo , NADP/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/genética , Oxirredutases atuantes sobre Doadores de Grupo CH-CH/isolamento & purificação , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Especificidade por Substrato , Temperatura
18.
Nat Prod Res ; : 1-7, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39084249

RESUMO

Two new sulphur-containing amides, glylucidamides C-D (1-2), along with twelve known analogues (3-14) were isolated and characterised from the leaves of Glycosmis lucida. The chemical structures of 1 and 2 were elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons their data with those reported in the literatures. All new compounds were evaluated for their anti-inflammatory activities via examining the inhibitory activity on nitric oxide (NO) production induced by lipopolysaccharide in mouse macrophage RAW 264.7 cells in vitro.

19.
Transfus Apher Sci ; 49(3): 600-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23972777

RESUMO

BACKGROUND: A variety of screening methods are currently used worldwide in order to decrease the risk of transfusion-transmitted sepsis and improve the safety of PCs. METHODS/MATERIALS: PCs inoculated with five different transfusion-relevant species of bacteria at concentrations of 1, 10, and 100 colony-forming units (CFU)ml(-1) were stored at 22°C for 7 days. Flow cytometry (FACS), BacT/Alert automated culturing, and a quantitative real-time PCR (Q-PCR) were then used to detect the presence of bacteria in samples prepared from these PCs. RESULTS: At the initial spiking concentrations of 1, 10, and 100 CFU ml(-1), Q-PCR detected all five bacterial species tested. Screening with the BacT/Alert culture-based system allowed bacterial detection (inoculated on day 0) within a mean time of 15.13 h for all three spiking concentrations. Using FACS, positive signals were obtained for all three concentrations of Escherichia coli and Bacillus cereus on day 1 and for initial spiking concentrations of Pseudomonas aeruginosa and Staphylococcus aureus of 1 CFU ml(-1) on day 2. For Staphylococcus epidermidis, detection of an initial inoculum of 1 CFU ml(-1) was possible only beginning on day 6. CONCLUSION: This study shows that under standard laboratory conditions the sensitivity of FACS in the detection of bacterial contamination of PCs was lower than that of either the BacT/Alert automated culturing method or Q-PCR.


Assuntos
Bactérias/isolamento & purificação , Plaquetas/microbiologia , Plaquetoferese/métodos , Bactérias/genética , Citometria de Fluxo/métodos , Humanos , Plaquetoferese/instrumentação , Reação em Cadeia da Polimerase em Tempo Real/métodos
20.
J Cloud Comput (Heidelb) ; 12(1): 49, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37007982

RESUMO

Teaching has become a complex essential tool for students' abilities, due to their different levels of learning and understanding. In the traditional offline teaching methods, dance teachers lack a target for students 'classroom teaching. Furthermore, teachers have limited time, so they cannot take full care of each student's learning needs according to their understanding and learning ability, which leads to the polarization of the learning effect. Because of this, this paper proposes an online teaching method based on Artificial Intelligence and edge calculation. In the first phase, standard teaching and student-recorded dance learning videos are conducted through the key frames extraction through a deep convolutional neural network. In the second phase, the extracted key frame images were then extracted for human key points using grid coding, and the fully convolutional neural network was used to predict the human posture. The guidance vector is used to correct the dance movements to achieve the purpose of online learning. The CNN model is distributed into two parts so that the training occurs at the cloud and prediction happens at the edge server. Moreover, the questionnaire was used to obtain the students' learning status, understand their difficulties in dance learning, and record the corresponding dance teaching videos to make up for their weak links. Finally, the edge-cloud computing platform is used to help the training model learn quickly form vast amount of collected data. Our experiments show that the cloud-edge platform helps to support new teaching forms, enhance the platform's overall application performance and intelligence level, and improve the online learning experience. The application of this paper can help dance students to achieve efficient learning.

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