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Water lilies belong to the angiosperm order Nymphaeales. Amborellales, Nymphaeales and Austrobaileyales together form the so-called ANA-grade of angiosperms, which are extant representatives of lineages that diverged the earliest from the lineage leading to the extant mesangiosperms1-3. Here we report the 409-megabase genome sequence of the blue-petal water lily (Nymphaea colorata). Our phylogenomic analyses support Amborellales and Nymphaeales as successive sister lineages to all other extant angiosperms. The N. colorata genome and 19 other water lily transcriptomes reveal a Nymphaealean whole-genome duplication event, which is shared by Nymphaeaceae and possibly Cabombaceae. Among the genes retained from this whole-genome duplication are homologues of genes that regulate flowering transition and flower development. The broad expression of homologues of floral ABCE genes in N. colorata might support a similarly broadly active ancestral ABCE model of floral organ determination in early angiosperms. Water lilies have evolved attractive floral scents and colours, which are features shared with mesangiosperms, and we identified their putative biosynthetic genes in N. colorata. The chemical compounds and biosynthetic genes behind floral scents suggest that they have evolved in parallel to those in mesangiosperms. Because of its unique phylogenetic position, the N. colorata genome sheds light on the early evolution of angiosperms.
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Genoma de Planta , Nymphaea/genética , Filogenia , Flores/genética , Flores/metabolismo , Nymphaea/metabolismo , Odorantes/análiseRESUMO
Multi-enzyme cascade catalysis has become an important technique for chemical reactions used in manufacturing and scientific study. In this research, we designed a four-enzyme integrated catalyst and used it to catalyse the deracemization reaction of cyclic chiral amines, where monoamine oxidase (MAO) catalyses the enantioselective oxidation of 1-methyl-1,2,3,4-tetrahydroisoquinoline (MTQ), imine reductase (IRED) catalyses the stereo selective reduction of 1-methyl-3,4-dihydroisoquinoline (MDQ), formate dehydrogenase (FDH) is used for the cyclic regeneration of cofactors, and catalase (CAT) is used for decomposition of oxidative reactions. The four enzymes were immobilized via polydopamine (PDA)-encapsulated dendritic organosilica nanoparticles (DONs) as carriers, resulting in the amphiphilic core-shell catalysts. The hydrophilic PDA shell ensures the dispersion of the catalyst in water, and the hydrophobic DON core creates a microenvironment with the spatial confinement effect of the organic substrate and the preconcentration effect to enhance the stability of the enzymes and the catalytic efficiency. The core-shell structure improves the stability and reusability of the catalyst and rationally arranges the position of different enzymes according to the reaction sequence to improve the cascade catalytic performance and cofactor recovery efficiency.
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Aminas , Monoaminoxidase , Polímeros , Aminas/química , Aminas/metabolismo , Monoaminoxidase/metabolismo , Monoaminoxidase/química , Polímeros/química , Polímeros/metabolismo , Formiato Desidrogenases/metabolismo , Formiato Desidrogenases/química , Catalase/química , Catalase/metabolismo , Indóis/química , Indóis/metabolismo , Estereoisomerismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Oxirredução , Nanopartículas/química , Biocatálise , Compostos de Organossilício/química , Oxirredutases/metabolismo , Oxirredutases/química , CatáliseRESUMO
Insect-induced plant volatile organic compounds (VOCs) may function as either direct defence molecules to deter insects or indirect defence signals to attract the natural enemies of the invading insects. Tea (Camellia sinensis L.), an important leaf-based beverage crop, is mainly infested by Ectropis obliqua which causes the most serious damage. Here, we report a mechanistic investigation of tea plant-derived VOCs in an indirect defence mechanism against E. obliqua. Parasitoid wasp Parapanteles hyposidrae, a natural enemy of E. obliqua, showed strong electrophysiological response and selection behaviour towards S-linalool and ß-ocimene, two monoterpenes with elevated emission from E. obliqua-damaged tea plants. Larvae frass of E. obliqua, which also released S-linalool and ß-ocimene, was found to attract both mated female or male Pa. hyposidrae according to gas chromatography-electroantennogram detection and Y-tube olfactometer assays. In a field setting, both S-linalool and ß-ocimene were effective in recruiting both female and male Pa. hyposidrae wasps. To understand the molecular mechanism of monoterpenes-mediated indirect defence in tea plants, two novel monoterpene synthase genes, CsLIS and CsOCS-SCZ, involved in the biosynthesis of S-linalool or ß-ocimene, respectively, were identified and biochemically characterised. When the expression of these two genes in tea plants was inhibited by antisense oligodeoxynucleotide, both volatile emission and attraction of wasps were reduced. Furthermore, gene expression analysis suggested that the expression of CsLIS and CsOCS-SCZ is regulated by the jasmonic acid signalling pathway in the tea plant.
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Monoterpenos Acíclicos , Alcenos , Camellia sinensis , Mariposas , Vespas , Animais , Monoterpenos , Camellia sinensis/genética , Sinais (Psicologia) , Mariposas/fisiologia , Insetos , CháRESUMO
The enantioselective synthesis of chiral diarylmethanols is highly desirable in synthetic chemistry and the pharmaceutical industry, but it remains challenging, especially in terms of green and sustainable production. Herein, a resin-immobilized palladium acetate catalyst was fabricated with high activity, stability, and reusability in Suzuki cross-coupling reaction of acyl halides with boronic acids, and the coimmobilization of alcohol dehydrogenase and glucose dehydrogenase on resin supports was also conducted for asymmetric bioreduction of diaryl ketones. Experimental results revealed that the physicochemical properties of the resins and the immobilization modes played important roles in affecting their catalytic performances. These two catalysts enabled the construction of a chemoenzymatic cascade for the enantioselective synthesis of a series of chiral diarylmethanols in high yields (83-90%) and enantioselectivities (87-98% ee). In addition, the asymmetric synthesis of the antihistaminic and anticholinergic drugs (S)-neobenodine and (S)-carbinoxamine was also achieved from the chiral diarylmethanol precursors, demonstrating the synthetic utility of the chemoenzymatic cascade.
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Álcool Desidrogenase , Paládio , Paládio/química , Estereoisomerismo , Estrutura Molecular , CatáliseRESUMO
Electrochemically converting NO3 - into NH3 offers a promising route for water treatment. Nevertheless, electroreduction of dilute NO3 - is still suffering from low activity and/or selectivity. Herein, B as a modifier was introduced to tune electronic states of Cu and further regulate the performance of electrochemical NO3 - reduction reaction (NO3 RR) with dilute NO3 - concentration (≤100â ppm NO3 - -N). Notably, a linear relationship was established by plotting NH3 yield vs. the oxidation state of Cu, indicating that the increase of Cu+ content leads to an enhanced NO3 - -to-NH3 conversion activity. Under a low NO3 - -N concentration of 100â ppm, the optimal Cu(B) catalyst displays a 100 % NO3 - -to-NH3 conversion at -0.55 to -0.6â V vs. RHE, and a record-high NH3 yield of 309â mmol h-1 gcat -1 , which is more than 25â times compared with the pristine Cu nanoparticles (12â mmol h-1 gcat -1 ). This research provides an effective method for conversion of dilute NO3 - to NH3 , which has certain guiding significance for the efficient and green conversion of wastewater in the future.
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Context: Lung carcinoma accounts for the majority of cancer deaths, and its 5-year survival rate isn't optimistic. Remarkable progress has been made in recent decades toward understanding the biological behavior of non-small-cell lung carcinoma (NSCLC) and creating targeted molecular therapies for diagnosis and treatment. However, little literature is available on the topic, and the clinical significance and application of miR-489-3p for NSCLC can't yet be determined. Objective: The study intended to determine if miR-489-3p can predict prognosis for patients with NSCLC. Design: The research team designed a prospective study to examine in depth and analyze the molecular science of NSCLC tumors in a clinical setting. Setting: The study took place in the Department of the Special Ward at the Shanxi Provincial Cancer Hospital in Taiyuan, Shanxi, China. Participants: Participants were 116 patients with NSCLC at the hospital and 87 healthy people. Outcome Measures: A type of microRNA (miRNA), MiR-489-3p, was detected using nano-polymerase chain reaction (PCR). The diagnostic value of miR-489-3p for lung carcinoma and its predictive value for death from the disease were analyzed using a receiver operating characteristic (ROC) curve, and the three-year prognosis for patients was examined. Human NSCLC cell lines and normal, human, lung epithelial cells were obtained, and miR-489-3p was detected to assess the biological effects on lung-cancer cells. Results: MiR-489-3p has low expression in lung-cancer tissues, which indicates its good predictive value for prognosis for and death of lung-cancer patients. The activity of tumor cells increased after the inhibition of miR-489-3p. Conclusions: A low level of miR-489-3p indicates a poor prognosis for patients with NSCLC. A deeper understanding of the mechanism of miR-489-3p in lung carcinoma may be the key to the earlier diagnosis and treatment of lung carcinoma.
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Carcinoma Pulmonar de Células não Pequenas , Carcinoma , Neoplasias Pulmonares , MicroRNAs , Biomarcadores , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Proliferação de Células , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Prognóstico , Estudos ProspectivosRESUMO
BACKGROUND: Three-dimensional computed tomography bronchography and angiography (3D-CTBA) provides detailed imaging information for pulmonary segmentectomy. This study was performed to verify the feasibility of 3D-CTBA-guided thoracoscopic segmentectomy for the treatment of pulmonary nodules. METHODS: A retrospective analysis was performed on all patients who underwent 3D-CTBA-guided uniport thoracoscopic segmentectomies or subsegmentectomies for pulmonary nodules in the period from May 2019 to May 2020. All of the information related to perioperative management and surgical operations was retrieved from the medical records and operating notes for detailed analysis. RESULTS: A total of 104 eligible operations involving the resection of 110 nodules with diameters in the range of 5-20 mm were included. Under 3D-CTBA guidance, the pulmonary nodules were located with an accuracy of 100% (110/110) and the median resection margin was 24.3 mm (17-33 mm). Additionally, the segmental (subsegmental) bronchi, arteries, and veins were identified with accuracy rates of 100% (104/104), 96.2% (100/104), and 94.2% (98/104), respectively. The postoperative complications consisted of 3 cases of pulmonary infection (2.9%), 6 cases of arrhythmia (5.8%), 2 cases of hemoptysis (1.9%), 4 cases of air leak (3.8%), and 2 cases of subcutaneous emphysema (1.9%). No perioperative death occurred. CONCLUSION: 3D-CTBA-guided thoracoscopic segmentectomy is an effective surgical approach for the management of pulmonary nodules.
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Broncografia , Neoplasias Pulmonares , Angiografia/métodos , Humanos , Imageamento Tridimensional/métodos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Mastectomia Segmentar , Pneumonectomia/métodos , Estudos Retrospectivos , Cirurgia Torácica Vídeoassistida/métodos , Tomografia Computadorizada por Raios XRESUMO
Although loose nanofiltration membranes have been extensively studied for dye desalination, high-throughput membranes with antifouling and antibacterial properties are still highly needed. In this study, a zwitterion-modified molybdenum disulfide (MoS2) dual-layer loose nanofiltration membrane was prepared with the integration of antibacterial, antifouling, and high-flux properties. To be specific, MoS2 nanosheets were loaded on a polyacrylonitrile ultrafiltration membrane through pressure-assisted self-assembly. Then, poly (sulfobetaine methacrylate) (PSBMA) was coated on the surface of the MoS2 membrane via a simple polydopamine (PDA)-assisted one-step codeposition to prepare PSBMA/PDA/MoS2 nanofiltration membranes. Elemental and morphological analyses confirmed the formation of the MoS2 layer and PSBMA/PDA coating. In addition, the effect of the PSBMA amount and codeposition time on surface properties and membrane performances was investigated. Under optimum conditions, the as-prepared membrane showed excellent water permeance of 262 LMH/bar with good dye rejection (99.8% for methylene blue) and salt permeability, as well as excellent antifouling and antibacterial properties benefiting from the synergy of PSBMA/PDA coating layers and MoS2 layers.
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To observe and analyze the effect of CT-guided drug injection around the nerve root in the treatment of lumbar disc herniation, the 140 patients diagnosed with lumbar disc herniation in our hospital, were selected as the study subjects for CT-guided drug injection around the nerve root and treatment efficacy was observed. According to the modified Mac Nab criteria, there were 80 cases, 50 cases, 6 cases, and 4 cases of excellent, good, fair, and poor results, with excellent and good rate at 92.86%; the patients whose onset time was less than three months and more than three months were compared in terms of VAS scores before and after surgery. The results showed that the postoperative pain score was significantly lower in patients whose onset time was less than three months compared to those whose onset time was more than three months, P<0.05; observation of patients' quality of life before and after treatment shows great improvement in quality of life after treatment, P<0.05. The treatment of lumbar disc herniation with CT-guided drug injection around the nerve root can achieve relatively good results with significantly improved therapeutic effect and great application value.
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Anti-Inflamatórios/uso terapêutico , Injeções Espinhais/métodos , Deslocamento do Disco Intervertebral/tratamento farmacológico , Vértebras Lombares , Salvia miltiorrhiza , Raízes Nervosas Espinhais/efeitos dos fármacos , Tomografia Computadorizada por Raios X , Adulto , Idoso , Anti-Inflamatórios/administração & dosagem , Meios de Contraste/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/efeitos dos fármacos , Medição da Dor/estatística & dados numéricos , Dor Pós-Operatória , Qualidade de Vida , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
This study examined the impacts of ultrasonic power (0, 150, 300, 450, 600, and 750 W) and ultrasonic durations (3, 6, 9, 12, and 15 min) on the physicochemical properties and microstructure of diacylglycerol (DAG)-loaded emulsions stabilized with soybean protein isolate (SPI) and sodium alginate (SA). The findings indicated that the smallest particle size, zeta potential, and contact angle for SPI-SA-DAG emulsions were respectively 5.58 µm, -49.85 mV, and 48.65°, achieved at an ultrasonic power of 450 W. The emulsification properties, loss modulus, storage modulus, and apparent viscosity of the emulsions were optimal at this power setting and at a duration of 9 min. Analytical techniques, including confocal laser scanning-, scanning electron-, and atomic force microscopy, revealed that ultrasonication significantly altered emulsion aggregation state, with the surface roughness (Rq) being minimized at 450 W. These results demonstrated that the stability of SPI-SA-DAG emulsions can be effectively enhanced by an appropriate ultrasonic treatment at 450 W for 9 min. This research provides theoretical support for the broad application of sonication techniques in the food industry.
Assuntos
Alginatos , Diglicerídeos , Emulsões , Proteínas de Soja , Alginatos/química , Proteínas de Soja/química , Diglicerídeos/química , Sonicação , Ácidos Hexurônicos/química , Ácido Glucurônico/química , Fenômenos Químicos , Tamanho da Partícula , Ondas UltrassônicasRESUMO
Tropospheric ozone (O3) pollution can affect plant nutritional quality and secondary metabolites by altering plant biochemistry and physiology, which may lead to unpredictable effects on crop quality and resistance to pests and diseases. Here, we investigated the effects of O3 (ambient air, Am; ambient air +80 ppb of O3, EO3) on the quality compounds and chemical defenses of a widely cultivated tea variety in China (Camellia sinensis cv. 'Baiye 1 Hao') using open-top chamber (OTC). We found that elevated O3 increased the ratio of total polyphenols to free amino acids while decreasing the value of the catechin quality index, indicating a reduction in leaf quality for green tea. Specifically, elevated O3 reduced concentrations of amino acids and caffeine but shows no impact on the concentrations of total polyphenols in tea leaves. Within individual catechins, elevated O3 increased the concentrations of ester catechins but not non-ester catechins, resulting in a slight increase in total catechins. Moreover, elevated O3 increased the emission of biogenic volatile organic compounds involved in plant defense against herbivores and parasites, including green leaf volatiles, aromatics, and terpenes. Additionally, concentrations of main chemical defenses, represented as condensed tannins and lignin, in tea leaves also increased in response to elevated O3. In conclusion, our results suggest that elevated ground-level O3 may reduce the quality of tea leaves but could potentially enhance the resistance of tea plants to biotic stresses.
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Direct synthesis of aliphatic amines from alkynes is highly desirable due to its atom economy and high stereoselectivity but still challenging, especially for the long-chain members. Here, a combination of Au-catalyzed alkyne hydration and amine dehydrogenase-catalyzed (AmDH) reductive amination was constructed, enabling sequential conversion of alkynes into chiral amines in aqueous solutions, particularly for the synthesis of long-chain aliphatic amines on a large scale. The production of chiral aliphatic amines with more than 6 carbons reached 36-60 g/L. A suitable biocatalyst [PtAmDH (A113G/T134G/V294A)], obtained by data mining and active site engineering, enabled the transformation of previously inactive long-chain ketones at high concentrations. Computational analysis revealed that the broader substrate scope and tolerance with the high substrate concentrations resulted from the additive effects of mutations introduced to the three gatekeeper residues 113, 134, and 294.
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Metal-enzyme integrated catalysts (MEICs) that combine metal and enzyme offer great potential for sustainable chemoenzymatic cascade catalysis. However, rational design and construction of optimal microenvironments and accessible active sites for metal and enzyme in individual nanostructures are necessary but still challenging. Herein, Pd nanoparticles (NPs) and Candida antarctica lipase B (CALB) are co-immobilized into the pores and surfaces of covalent organic frameworks (COFs) with tunable functional groups, affording Pd/COF-X/CALB (X = ONa, OH, OMe) MEICs. This strategy can regulate the microenvironment around Pd NPs and CALB, and their interactions with substrates. As a result, the activity of the COF-based MEICs in catalyzing dynamic kinetic resolution of primary amines is enhanced and followed COF-OMe > COF-OH > COF-ONa. The experimental and simulation results demonstrated that functional groups of COFs modulated the conformation of CALB, the electronic states of Pd NPs, and the affinity of the integrated catalysts to the substrate, which contributed to the improvement of the catalytic activity of MEICs. Further, the MEICs are prepared using COF with hollow structure as support material, which increased accessible active sites and mass transfer efficiency, thus improving catalytic performance. This work provides a blueprint for rational design and preparation of highly active MEICs.
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Organometallic catalyst is extensively applied for the non-enzymatic regeneration of nicotinamide adenine dinucleotide (phosphate) cofactors, but suffering from the mutual inactivation with the enzymes in one pot. The spatially separated immobilization of organometallic catalyst and enzymes on suitable carriers not only can reduce their mutual inhabitation but also can enhance their reusability. Here in this work, we present a hierarchical porous COFs (HP-TpBpy) that incorporated with [(Cp*RhCl2]2 to generate the metalized COF, Rh-HP-TpBpy. The obtained Rh-HP-TpBpy exhibited superior performance in nicotinamide adenine dinucleotide (NADH) and nicotinamide adenine dinucleotide phosphate (NADPH) regeneration using formate as the hydride donor, significantly outperforming the natural formate dehydrogenases in cofactor preference toward NADP+. Subsequently, the Lactobacillus fermentum short-chain dehydrogenase/reductase 1 (LfSDR1) was then cross-linked into enzyme aggregates (CLEA) and immobilized on hierarchical Rh-HP-TpBpy, achieving the integrated chemoenzymatic catalyst, LfSDR1@Rh-HP-TpBpy, which can catalyze the chemoenzymatic reduction of halogenated aryl ketones and give the corresponding optically active halohydrins with high conversion and enantiomeric excess (ee) value up to 99 %. The LfSDR1@Rh-HP-TpBpy also exhibits largely enhanced stability compared with the free LfSDR1 and the CLEAs-LfSDR1, enabling its excellent reusability.
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Chemoenzymatic cascade catalysis has emerged as a revolutionary tool for streamlining traditional retrosynthetic disconnections, creating new possibilities for the asymmetric synthesis of valuable chiral compounds. Here we construct a one-pot concurrent chemoenzymatic cascade by integrating organobismuth-catalyzed aldol condensation with ene-reductase (ER)-catalyzed enantioselective reduction, enabling the formal asymmetric α-benzylation of cyclic ketones. To achieve this, we develop a pair of enantiocomplementary ERs capable of reducing α-arylidene cyclic ketones, lactams, and lactones. Our engineered mutants exhibit significantly higher activity, up to 37-fold, and broader substrate specificity compared to the parent enzyme. The key to success is due to the well-tuned hydride attack distance/angle and, more importantly, to the synergistic proton-delivery triade of Tyr28-Tyr69-Tyr169. Molecular docking and density functional theory (DFT) studies provide important insights into the bioreduction mechanisms. Furthermore, we demonstrate the synthetic utility of the best mutants in the asymmetric synthesis of several key chiral synthons.
Assuntos
Aldeídos , Cetonas , Estrutura Molecular , Simulação de Acoplamento Molecular , Aldeídos/química , Catálise , Cetonas/química , EstereoisomerismoRESUMO
Photocatalysis is an eco-friendly method to regenerate nicotinamide (NADH) cofactors, which is essential for biotransformation over oxidoreductases. Organic polymers exhibit high stability, biocompatibility and functional designability as photocatalysts, but still suffering from rapid charge recombination. Herewith the heteroatom structural engineering of donor-π-acceptor (D-π-A) conjugated porous polymers were conducted to promote charge transfer and photocatalytic NADH regeneration. The electron delocalization of polymer photocatalysts can be readily tuned by changing the electron density of the donor unit, leading to faster charge separation and better photocatalytic performance. The optimum sulfur-doped polymer exhibits the highest NADH regeneration yield of 47.4 % in 30â min and 94.1 % in 4â h, which can drive the biocatalytic C=C bond reduction of 2-cyclohexen-1-one by ene-reductase, giving the corresponding cyclohexanone yield of 96.7 % in 10â h. Moreover, the oxygen-doped polymer, from biomass derived 2,5-diformylfuran, exhibits comparable photocatalytic activity to the sulfur-doped CPP, suggesting the potential of furan as alternative donor unit to thiophene.
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Multiple infections of Bordetella avium (B. avium) with virus, especially immunosuppressive virus, have become more and more severe in chickens in China. The increasing morbidity and mortality of its complications have amplified concerns about the impact of B. avium on animal health. To evaluate the pathogenicity of B. avium under immunosuppression status, we developed four types of Reticuloendotheliosis virus (REV) infection models. After a comparison of body weight, relative immune organ index, Newcastle disease virus antibody titers and lymphocyte ratio, we chose the early age with low dose infection as our immunosuppressive model. To investigate the pathogenicity of B. avium under this model, a study was completed in which chickens were inoculated with REV-only, B. avium-only, both agents (REV -B. avium) or first inoculated with REV and 5 d later with B. avium (REV/B. avium). Results revealed that antibody titers to B. avium, concentrations of IFN-γ and SIgA were decreased in coinfected chickens when compared to the B. avium-only chickens, but the changing trend was similar between REV/B. avium and B. avium-only groups. Overall, REV did enhance the pathogenicity of B. avium. However, B. avium-only did not cause severe immune dysfunction unless chicks were coinfected with REV. REV preceding infection with B. avium showed mild impairment, which needs further exploration.
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Infecções por Bordetella/patologia , Bordetella avium/patogenicidade , Hospedeiro Imunocomprometido , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/patologia , Infecções por Retroviridae/complicações , Organismos Livres de Patógenos Específicos , Animais , Infecções por Bordetella/imunologia , Infecções por Bordetella/microbiologia , Galinhas , China , Coinfecção/imunologia , Coinfecção/microbiologia , Coinfecção/patologia , Coinfecção/virologia , DNA Bacteriano/química , DNA Bacteriano/genética , Modelos Animais de Doenças , Imunoglobulina A Secretora/sangue , Terapia de Imunossupressão , Interferon gama/sangue , Dados de Sequência Molecular , Vírus da Reticuloendoteliose/imunologia , Vírus da Reticuloendoteliose/patogenicidade , Infecções por Retroviridae/imunologia , Análise de Sequência de DNARESUMO
This study was conducted to evaluate the radioactivity level in the granite building raw material production area in Cenxi, China. Natural radionuclide concentrations, γ absorbed dose rates (ADRs) and radon exhalation rates were measured in the area. The spatial distribution of natural radionuclides, γ ADR and radon exhalation rate were mapped with GPS information. The radioactivity levels in the study area were analysed based on the descriptive statistics and frequency distribution of measurement data. According to the Chinese standard, the granite raw materials used for building and decoration in this region were classified based on their radiological hazards. In addition, radiation protection measures were proposed for the mining of local granite building materials products as well as environmental protection around the work area and resident safety.
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Nymphaea is a key genus of the ANA grade (Amborellales, Nymphaeales, and Austrobaileyales) of basal flowering plants, which serve as a key model to study the early evolution of floral traits. In this study, we comprehensively investigated the emission, biosynthesis, and biological function of the floral scent in a night-blossoming waterlily Nymphaea prolifera. The headspace volatile collection combined with GC-MS analysis showed that the floral scent of N. prolifera is predominately comprised by methylated benzenoids including anisole, veratrole, guaiacol, and methoxyanisole. Moreover, the emission of these floral benzenoids in N. prolifera exhibited temporal and spatial pattern with circadian rhythm and tissue specificity. By creating and mining transcriptomes of N. prolifera flowers, 12 oxygen methyltransferases (NpOMTs) were functionally identified. By in vitro enzymatic assay, NpOMT3, 6, and 7 could produce anisole and NpOMT5, 7, 9, produce guaiacol, whereas NpOMT3, 6, 9, 11 catalyzed the formation of veratrole. Methoxyanisole was identified as the universal product of all NpOMTs. Expression patterns of NpOMTs provided implication for their roles in the production of the respective benzenoids. Phylogenetic analysis of OMTs suggested a Nymphaea-specific expansion of the OMT family, indicating the evolution of lineage-specific functions. In bioassays, anisole, veratrole, and guaiacol in the floral benzenoids were revealed to play the critical role in repelling waterlily aphids. Overall, this study indicates that the basal flowering plant N. prolifera has evolved a diversity and complexity of OMT genes for the biosynthesis of methylated benzenoids that can repel insects from feeding the flowers. These findings provide new insights into the evolutional mechanism and ecological significance of the floral scent from early-diverged flowering plants.
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Cascade catalysis that combines chemical catalysis and biocatalysis has received extensive attention in recent years, especially the integration of metal nanoparticles (MNPs) with enzymes. However, the compatibility between MNPs and enzymes, and the stability of the integrated nanocatalyst should be improved to promote the application. Therefore, in this study, we proposed a strategy to space-separately co-immobilize MNPs and enzymes to the pores and surface of a highly stable covalent organic framework (COF), respectively. Typically, Pd NPs that were prepared by in situ reduction with triazinyl as the nucleation site were distributed in COF (Tz-Da), and organophosphorus hydrolase (OPH) was immobilized on the surface of Tz-Da by a covalent method to improve its stability. The obtained integrated nanocatalyst Pd@Tz-Da@OPH showed high catalytic efficiency and reusability in the cascade degradation of organophosphate nerve agents. Furthermore, the versatility of the preparation strategy of COF-based integrated nanocatalyst has been preliminarily expanded: (1) Pd NPs and OPH were immobilized in the triazinyl COF (TTB-DHBD) with different pore sizes for cascade degradation of organophosphate nerve agent and the particle size of MNPs can be regulated. (2) Pt NPs and glucose oxidase were immobilized in COF (Tz-Da) to obtain an integrated nanocatalyst for efficient colorimetric detection of phenol.