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1.
Nature ; 580(7802): 201-204, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32269343

RESUMO

Distributing entanglement over long distances using optical networks is an intriguing macroscopic quantum phenomenon with applications in quantum systems for advanced computing and secure communication1,2. Building quantum networks requires scalable quantum light-matter interfaces1 based on atoms3, ions4 or other optically addressable qubits. Solid-state emitters5, such as quantum dots and defects in diamond or silicon carbide6-10, have emerged as promising candidates for such interfaces. So far, it has not been possible to scale up these systems, motivating the development of alternative platforms. A central challenge is identifying emitters that exhibit coherent optical and spin transitions while coupled to photonic cavities that enhance the light-matter interaction and channel emission into optical fibres. Rare-earth ions in crystals are known to have highly coherent 4f-4f optical and spin transitions suited to quantum storage and transduction11-15, but only recently have single rare-earth ions been isolated16,17 and coupled to nanocavities18,19. The crucial next steps towards using single rare-earth ions for quantum networks are realizing long spin coherence and single-shot readout in photonic resonators. Here we demonstrate spin initialization, coherent optical and spin manipulation, and high-fidelity single-shot optical readout of the hyperfine spin state of single 171Yb3+ ions coupled to a nanophotonic cavity fabricated in an yttrium orthovanadate host crystal. These ions have optical and spin transitions that are first-order insensitive to magnetic field fluctuations, enabling optical linewidths of less than one megahertz and spin coherence times exceeding thirty milliseconds for cavity-coupled ions, even at temperatures greater than one kelvin. The cavity-enhanced optical emission rate facilitates efficient spin initialization and single-shot readout with conditional fidelity greater than 95 per cent. These results showcase a solid-state platform based on single coherent rare-earth ions for the future quantum internet.

2.
Inorg Chem ; 63(9): 4447-4460, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38385361

RESUMO

Photocatalytic coupling technologies have emerged as popular strategies to increase the treatment efficiency of dye-containing wastewater. Herein, the Z-scheme Co3O4/BiOBr heterojunction (Z-CBH) was constructed and developed as a photocatalytic peroxydisulfate (PDS) activator for the degradation of high-concentration Rhodamine B (RhB). Multiple testing techniques were employed to confirm the formation of Z-CBHs. When 0.1 g·L-1 of Z-CBH20 and 1.0 mmol·L-1 of PDS were added simultaneously under simulated sunlight irradiation, the RhB degradation efficiency could approach 91.3%. Its reaction rate constant (0.01231 min-1) was much beyond the sum of those in the Z-CBH20/light system (0.00436 min-1) and the PDS/light system (0.0062 min-1). h+, •OH, •O2-, SO4•-, and 1O2 were detected as the dominant reactive species for RhB degradation. The potential mechanism of photocatalytic PDS oxidation was proposed. The possible intermediates were determined by high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry assisted with density functional theory and Fukui theory. The possible degradation pathways of RhB degradation were put forward. The toxicological properties of RhB and its intermediates were evaluated by quantitative structure-activity relationship prediction. This work will not only provide a reference for developing photocatalytic persulfate activators but also gain an insight into the degradation pathways of RhB and the toxicity of its intermediates.

3.
Inorg Chem ; 63(14): 6500-6513, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38532637

RESUMO

It is a challenging task to design a piezoelectric photocatalyst with excellent performance under mechanical agitation instead of ultrasonic irradiation. Integrating vacancy defects into a heterojunction seems to be an effective strategy for synergistically increasing its piezo-photocatalytic performance. For this goal, a two-step hydrothermal method was adopted to architect a type-I oxygen-vacancy-rich BaTiO3/BiOBr heterojunction to surge the degradation of Rhodamine B (RhB) under the combined action of simulated sunlight irradiation and mechanical agitation. Various instrumental techniques demonstrated the formation of a BaTiO3/BiOBr heterojunction with high crystallinity. The existence of surface oxygen vacancies was confirmed by XPS and EPR tests. PFM results manifested that this heterojunction had excellent piezoelectric properties, with a piezoelectric response value of 30.31 pm V-1. Comparative experiments indicated that RhB degradation efficiency under piezo-photocatalysis over this heterojunction largely exceeded the total sum of those under piezocatalysis and photocatalysis. h+, ·O2-, and 1O2 were the dominant reactive species for RhB degradation. The improved separation efficiency of photogenerated charges was verified by electrochemical measurements. DFT calculations indicated that the polarization of BaTiO3 could affect the electronic band structure of BiOBr. This work will provide comprehensive insights into piezo-photocatalytic mechanism at a microcosmic level and help to develop new-styled piezoelectric photocatalysts.

4.
J Appl Clin Med Phys ; 25(3): e14195, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37915300

RESUMO

OBJECTIVE: Surface-guided radiation therapy (SGRT, AlignRT) was used to analyze motion during stereotactic body radiotherapy (SBRT) in lung cancer patients and to explore the margin of the planning target volume (PTV). METHODS: The residual errors of the AlignRT were evaluated based on grayscale cone-beam computed tomography registration results before each treatment. AlignRT log file was used to analyze the correlation between the frequency and longest duration of errors larger than 2 mm and lasting longer than 2 s and maximum error with age and treatment duration. The displacement value at the end of treatment, the average displacement value, and the 95% probability density displacement interval were defined as intrafraction errors, and PTV1, PTV2, PTV3 were calculated by Van Herk formula or Z score analysis. Organ dosimetric differences were compared after the experience-based margin was replaced with PTV3. RESULTS: The interfraction residual errors were Vrt0 , 0.06 ± 0.18 cm; Lng0 , -0.03 ± 0.19 cm; Lat0 , 0.02 ± 0.15 cm; Pitch0 , 0.23 ± 0.7°; Roll0 , 0.1 ± 0.69°; Rtn0 , -0.02 ± 0.79°. The frequency, longest duration and maximum error in vertical direction were correlated with treatment duration (r = 0.404, 0.353, 0.283, p < 0.05, respectively). In the longitudinal direction, the frequency was correlated with age and treatment duration (r = 0.376, 0.283, p < 0.05, respectively), maximum error was correlated with age (r = 0.4, P < 0.05). Vertical, longitudinal, lateral margins of PTV1, PTV2, PTV3 were 2 mm, 4 mm, 2 mm; 2 mm, 2 mm, 2 mm, 3 mm, 5 mm, 3 mm, respectively. After replacing the original PTV, mean lung dose (MLD), 2-cm3 chest wall dose (CD), lung V20 decreased by 0.2 Gy, 2.1 Gy, 0.5%, respectively (p < 0.05). CONCLUSION: AlignRT can be used for interfraction setup and monitoring intrafraction motion. It is more reasonable to use upper and lower limits of the 95% probability density interval as an intrafraction error.


Assuntos
Neoplasias Pulmonares , Radiocirurgia , Radioterapia Guiada por Imagem , Humanos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Radiocirurgia/métodos , Radioterapia Guiada por Imagem/métodos , Pulmão , Tomografia Computadorizada de Feixe Cônico , Planejamento da Radioterapia Assistida por Computador/métodos , Erros de Configuração em Radioterapia/prevenção & controle
5.
Nanotechnology ; 32(26)2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33361556

RESUMO

Characterizing electrical breakdown limits of materials is a crucial step in device development. However, methods for repeatable measurements are scarce in two-dimensional materials, where breakdown studies have been limited to destructive methods. This restricts our ability to fully account for variability in local electronic properties induced by surface contaminants and the fabrication process. To tackle this, we implement a two-step deep-learning model to predict the breakdown mechanism and breakdown voltage of monolayer MoS2devices with varying channel lengths and resistances using current measured in the low-voltage regime as inputs. A deep neural network (DNN) first classifies between Joule and avalanche breakdown mechanisms using partial current traces from 0 to 20 V. Following this, a convolutional long short-term memory network (CLSTM) predicts breakdown voltages of these classified devices based on partial current traces. We test our model with electrical measurements collected using feedback-control of the applied voltage to prevent device destruction, and show that the DNN classifier achieves an accuracy of 79% while the CLSTM model has a 12% error when requiring only 80% of the current trace as inputs. Our results indicate that information encoded in the current behavior far from the breakdown point can be used for breakdown predictions, which will enable non-destructive and rapid material characterization for 2D material device development.

6.
Dermatol Ther ; 33(3): e13389, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32268443

RESUMO

Discoid lupus erythematosus (DLE) is a chronic autoimmune skin disease that usually causes disfiguring scarring, dyspigmentation, and atrophy. Despite a range of available topical and systemic therapies, the treatment of DLE remains a therapeutic challenge, especially in some refractory cases. Here, we reported three male patients with long-term chronic lesions of unilateral facial localized DLE, who failed to have their disease controlled with many previous topical/systemic treatments, showed rapid and well response to intralesional injections of betamethasone (2 mg/mL, 0.2 mL/site) monotherapy once every 2 weeks for two, two, and four times of treatment, respectively. Intralesional betamethasone may provide a safe and effective alternative in the management of refractory localized DLE skin lesions.


Assuntos
Betametasona , Lúpus Eritematoso Discoide , Administração Cutânea , Administração Tópica , Betametasona/uso terapêutico , Cicatriz , Humanos , Lúpus Eritematoso Discoide/diagnóstico , Lúpus Eritematoso Discoide/tratamento farmacológico , Masculino
7.
Water Sci Technol ; 81(5): 1080-1089, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32541124

RESUMO

Bismuth oxyhalides (BiOXs, X = Cl, Br and I) are emerging photocatalytic materials with unique layered structure, flexible band structure and superior photocatalytic activity. The purpose of this study was to develop a facile alcoholysis route to prepare BiOClxI1-x nanosheet solid solutions at room temperature. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), UV-vis diffuse reflectance spectroscopy (UV-vis DRS), photoluminescence emission spectroscopy (PL) and Brunauer-Emmett-Teller (BET) surface area analyzer were used to characterize the as-prepared photocatalysts. These results revealed that two-dimension BiOClxI1-x nanosheet solid solutions could be obtained with high percentage of {001} crystal facets exposed. Moreover, the formation of solid solution could regularly change the optical absorption thresholds and band gaps of BiOClxI1-x photocatalysts. The photocatalytic experiments indicated that BiOCl0.75I0.25 exhibited the highest photocatalytic performance for the degradation of Rhodamine B (RhB) under simulated sunlight irradiation and the photocatalytic process followed a pseudo-first-order kinetic equation. A possible mechanism of RhB photodegradation over BiOClxI1-x solid solutions was proposed based on the structural properties of BiOClxI1-x solid solutions and RhB photosensitization.


Assuntos
Luz , Água , Catálise , Rodaminas
8.
Acta Biochim Biophys Sin (Shanghai) ; 51(2): 197-203, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30590376

RESUMO

Perioperative hyperglycemia is a common metabolic disorder in clinic settings. Hyperglycemia leads to endothelial inflammation, endothelial cell apoptosis, and dysfunction, thus resulting in endothelial injury. Propofol (2,6-diisopropylphenol) is a widely used intravenous anesthetic in clinic settings. Our previous study indicated that propofol inhibits mitochondrial reactive oxygen species (ROS) production via down-regulation of phosphatase A2 (PP2A) expression, inhibition of Ser36-p66shc dephosphorylation and mitochondrial translocation, thus improving high glucose-induced endothelial injury. The expression of p66shc was inhibited by propofol in hyperglycemic human umbilical vein endothelial cells (HUVECs). However, the mechanism by which propofol inhibits p66shc expression in hyperglycemic HUVECs is still obscure. In the present study, we mainly examined how propofol inhibited high glucose-induced p66shc expression in HUVECs. Compared with 5 mM glucose treatment, high glucose increased p66shc expression and decreased sirt1 expression, which was inhibited by propofol treatment. Moreover, EX527 (a sirt1 inhibitor) reversed the effect of propofol against high glucose-induced p66shc expression. However, EX527 did not reverse the effects of propofol against high glucose-induced ROS accumulation, endothelial inflammation, and apoptosis. Furthermore, when cells were incubated with propofol, EX527, and FTY720 (a PP2A activator) simultaneously, the effects of propofol against high glucose-induced ROS accumulation, inflammation, and apoptosis were reversed. Our results suggested that propofol inhibited high glucose-induced p66shc expression via upregulation of sirt1 expression in hyperglycemic HUVECs. Moreover, propofol protects against high glucose-mediated ROS accumulation and endothelial injury via both inhibition of p66shc expression and dephosphorylation of Ser36-p66shc.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Propofol/farmacologia , Sirtuína 1/genética , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/genética , Anestésicos Intravenosos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Caspase 3/genética , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Fosforilação/efeitos dos fármacos , Sirtuína 1/metabolismo , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src/metabolismo
9.
Angew Chem Int Ed Engl ; 58(8): 2448-2453, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30600893

RESUMO

Heterogeneous, metal, single-site catalysts often exhibit higher catalytic performance than other catalysts because of their maximized atom efficiency of 100 %. Reported herein is a precoordination/solvothermal polymerization strategy to fabricate a stable mononuclear Pd-metalized porous organic polymer catalyst (Pd@POP). Pd@POP was easy to use in regioselective organic reactions because the internal structure of this Pd@POP can be easily modified. The catalyst was used to solve the intractable regioselectivity problems of Heck reactions. Pd@POP-9 can efficiently activate the ends of olefins, thereby leading to high selectivity for substitution at the external position. To understand the reason underlying the high selectivity and activity of the catalyst, the systemic characterization of Pd@POP-9 and density-functional theory calculations were conducted. This Heck reaction is the first to be catalyzed by a recyclable mononuclear metal catalyst with unprecedented catalytic activity and regioselectivity.

10.
Water Sci Technol ; 77(11-12): 2929-2939, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30065145

RESUMO

The development of a catalyst with high catalytic activity was one of the most important issues for the heterogeneous Fenton-like process. In this study, nanocomposites of Fe3O4 anchored onto reduced graphene oxide (RGO) were prepared by a moderate alkaline-thermal precipitation method and developed as highly efficient heterogeneous Fenton-like catalysts. The characterization results indicated that Fe3O4 nanoparticles (NPs) were tightly anchored onto few-layer RGO sheets via a strong interaction. Contrast experiments showed that Fe3O4/RGO nanocomposites had much better Fenton-like catalytic activity than Fe3O4 NPs. The process optimization of methyl orange (MO) discoloration in Fe3O4/RGO-H2O2 system was accomplished by central composite design under response surface methodology. A second-order polynomial model was established to predict the optimal values of MO discoloration and its significance was evaluated by analysis of variance. Three-dimensional response surfaces for the interaction between two variables were constructed. Based on the model prediction, the optimum conditions for MO discoloration in Fe3O4/RGO-H2O2 system were 2.9 for solution pH, 16.5 mM H2O2 concentration, 2.5 g/L catalyst dosage and 33.5 min of reaction time, with the maximum predicted value for MO discoloration ratio of 99.98%.


Assuntos
Compostos Azo/química , Grafite/química , Modelos Químicos , Nanopartículas/química , Poluentes Químicos da Água/química , Catálise , Cor , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Ferro/química , Microscopia Eletrônica de Transmissão , Óxidos/química , Análise Espectral Raman , Difração de Raios X
11.
J Reprod Dev ; 62(1): 71-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26537205

RESUMO

Nuclear reprogramming induced by somatic cell nuclear transfer is an inefficient process, and donor cell DNA methylation status is thought to be a major factor affecting cloning efficiency. Here, the role of donor cell DNA methylation status regulated by 5-aza-2'-deoxycytidine (5-aza-dC) or 5-methyl-2'-deoxycytidine-5'-triphosphate (5-methyl-dCTP) in the early development of porcine cloned embryos was investigated. Our results showed that 5-aza-dC or 5-methyl-dCTP significantly reduced or increased the global methylation levels and altered the methylation and expression levels of key genes in donor cells. However, the development of cloned embryos derived from these cells was reduced. Furthermore, disrupted pseudo-pronucleus formation and transcripts of early embryo development-related genes were observed in cloned embryos derived from these cells. In conclusion, our results demonstrated that alteration of the DNA methylation status of donor cells by 5-aza-dC or 5-methyl-dCTP disrupted nuclear reprogramming and impaired the developmental competence of porcine cloned embryos.


Assuntos
Clonagem de Organismos/métodos , Metilação de DNA , Animais , Azacitidina/análogos & derivados , Azacitidina/química , Blastocisto/metabolismo , Núcleo Celular/metabolismo , Células Cultivadas , Reprogramação Celular , Decitabina , Nucleotídeos de Desoxicitosina/química , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário/efeitos dos fármacos , Fertilização in vitro , Fibroblastos/metabolismo , Genoma , Oócitos/citologia , Suínos
12.
J Dairy Sci ; 99(5): 3305-3315, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26947286

RESUMO

The influence of the molecular weight (Mw; 270, 750, and 2,500 kDa) and concentration of carboxymethylcellulose (CMC) on the stability and properties of whey protein isolate (WPI)-stabilized oil-in-water emulsions were assessed by measuring ζ-potential, droplet size, apparent viscosity, protein surface coverage, and creaming stability. Emulsions were prepared to contain 5% oil, 0.5% WPI, and 0 to 0.5% CMC at pH 7. After emulsification, pH was adjusted to 5.2. In the absence of CMC, the WPI-stabilized emulsion was unstable to droplet flocculation and coalescence due to the relatively low droplet charge. Emulsions stabilized by mixed WPI-CMC had improved surface properties as well as reduced droplet flocculation, as indicated by increased negative charges and protein surface coverage as well as smaller droplet size. Increased viscosity due to nonadsorbed CMC also contributed to increased stability at high CMC concentration. The high-Mw CMC was more effective in enhancing surface properties and providing better stability against creaming compared with lower-Mw CMC. Maximum stability was achieved with mixed WPI-CMC stabilized emulsion containing 0.08% CMC 2,500 kDa.


Assuntos
Emulsões/química , Proteínas do Soro do Leite , Animais , Carboximetilcelulose Sódica , Concentração de Íons de Hidrogênio , Proteínas do Leite/química , Peso Molecular , Água/química
13.
Water Sci Technol ; 74(10): 2417-2426, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27858798

RESUMO

Due to the difficult separation of superfine schorl powder (SSP) from solution after being used, millimetre-scale porous schorl ceramisite (PSC) was obtained through solid-phase sintering method and used as a heterogeneous catalyst for Fenton-like discoloration of organic dyes. SSP and PSC were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and field emission scanning electron microscopy. The results demonstrated that both SSP and PSC were mainly composed of schorl and there existed large amounts of micropores on the surface of PSC. A series of control experiments indicated that PSC exhibited higher Fenton-like catalytic activity than SSP. Methylene blue (MB) discoloration in both PSC-H2O2 and SSP-H2O2 systems followed pseudo-first-order kinetics and the reaction rate constant k1 obtained in PSC-H2O2 system was 3.23 times as large as the one in SSP-H2O2 system. Then, the process optimization of MB discoloration in heterogeneous Fenton-like reaction catalyzed by PSC was operated by central composite design under response surface methodology. Based on the model prediction, the optimum conditions for MB discoloration in this system were determined.


Assuntos
Corantes/química , Peróxido de Hidrogênio/química , Azul de Metileno/química , Silicatos/química , Poluentes Químicos da Água/química , Catálise , Cinética , Porosidade , Purificação da Água/métodos , Difração de Raios X
14.
J Surg Res ; 193(1): 324-33, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25255722

RESUMO

BACKGROUND: The choice between volar locking plates (VLP) and external fixation (EF) for unstable distal radius fractures have not reached a consensus. The meta-analysis of randomized controlled trials was performed to compare VLP with EF to determine the dominant strategy. MATERIALS AND METHODS: Meta-analysis was performed with a systematic search of studies conducted by using the PubMed, Embase, and Cochrane Central Register of Controlled Trials databases. The randomized controlled trials that compared VLP with EF was identified. Characteristics, functional outcomes, radiological results, and complications were manually extracted from all the selected studies. RESULTS: Six studies encompassing 445 patients met the inclusion criteria. There was significant difference between two procedures in disabilities of the arm shoulder and hand scores at 3,6, and 12 mo, visual analogue scale at 6 mo, grip strength at 3 mo, supination at 3 and 6 mo, extension at 3 mo, ulnar variance at 12 mo, and reoperation rate at 12 mo, postoperatively. However, there was no significant difference between flexion, pronation, radial deviation, and ulnar deviation at all follow-up points postoperatively and overall complications at 12 mo, postoperatively. CONCLUSIONS: EF had less reoperative rate due to complications, however, VLP had advantages in functional recovery in the early period after surgery, but two methods had similar functional recovery at 12 mo, postoperatively. Clinician should make the treatment decision with great caution for the patients who sustained unstable distal radial fractures.


Assuntos
Placas Ósseas , Fixadores Externos , Placa Palmar/cirurgia , Fraturas do Rádio/cirurgia , Avaliação da Deficiência , Humanos , Placa Palmar/diagnóstico por imagem , Radiografia , Fraturas do Rádio/diagnóstico por imagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica
15.
J Reprod Dev ; 60(5): 377-82, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25047549

RESUMO

Incomplete DNA methylation reprogramming in cloned embryos leads to low cloning efficiency. Our previous studies showed that the epigenetic modification agents 5-aza-2'-deoxycytidine (5-aza-dC) or trichostatin A (TSA) could enhance the developmental competence of porcine cloned embryos. Here, we investigated genomic methylation dynamics and specific gene expression levels during early embryonic development in pigs. In this study, our results showed that there was a typical wave of DNA demethylation and remethylation of centromeric satellite repeat (CenRep) in fertilized embryos, whereas in cloned embryos, delayed demethylation and a lack of remethylation were observed. When cloned embryos were treated with 5-aza-dC or TSA, CenRep methylation reprogramming was improved, and this was similar to that detected in fertilized counterparts. Furthermore, we found that the epigenetic modification agents, especially TSA, effectively promoted silencing of tissue specific genes and transcription of early embryo development-related genes in porcine cloned embryos. In conclusion, our results showed that the epigenetic modification agent 5-aza-dC or TSA could improve genomic methylation reprogramming in porcine cloned embryos and regulate the appropriate expression levels of genes related to early embryonic development, thereby resulting in high developmental competence.


Assuntos
Clonagem de Organismos/veterinária , Metilação de DNA/genética , Epigênese Genética , Suínos/embriologia , Suínos/genética , Animais , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Reprogramação Celular , Clonagem de Organismos/métodos , Decitabina , Técnicas de Cultura Embrionária , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/genética , Epigênese Genética/efeitos dos fármacos , Fertilização in vitro/veterinária , Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Técnicas de Transferência Nuclear/veterinária
16.
Chemosphere ; 362: 142597, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38889873

RESUMO

In the past decades, the amount of biomass waste has continuously increased in human living environments, and it has attracted more and more attention. Biomass is regarded as the most high-quality and cost-effective precursor material for the preparation carbon of adsorbents and catalysts. The application of biomass carbon has extensively explored. The efficient application of biomass carbon in organic wastewater purification were reviewed. With briefly introducing biomass types, the latest progress of Machine learning in guiding the preparation and application of biomass carbon was emphasized. The key factors in constructing efficient biomass carbon for adsorption and catalytic applications were discussed. Based on the functional groups, rich pore structure and active site of biomass carbon, it exhibits high efficiency in water purification performance in the fields of adsorption and catalysis. In addition, out of a firm belief in the enormous potential of biomass carbon, the remaining challenges and future research directions were discussed.

17.
Fitoterapia ; 176: 105976, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38685511

RESUMO

Phytochemical research on an extract of Notopterygium incisum yielded fifteen compounds (1-15), including four previously undescribed compounds (10-13). The structures of the unreported compounds were elucidated by spectroscopic and spectrometric data analysis such as 1D and 2D NMR, IR and HR-ESI-MS. Compounds 1-5 and 10-14 were isolated from N. incisum for the first time. 7S⁎,8R⁎-Phenethyl-(7-methoxy-8-isoeugenol)-ferulate (10), 7S⁎,8R⁎-p-hydroxyphenethyl-(7-methoxy-8-isoeugenol)-ferulate (11), 7S⁎,8R⁎-benzyl-(7-methoxy-8-isoeugenol)-ferulate (12) and p-hydroxyphenethyl-(4-benzoy-3-methoxy)-cinnamate (13) are the undescribed ferulic acid derivatives. Additionly, the anti-neuroinflammatory effects of compounds were evaluated in lipopolysaccharide (LPS)-induced BV2 cells. The pharmacological results showed that 6ß,10ß-epoxy-4α-hydroxy-guaiane (6), teuclatriol (7) and 7S⁎,8R⁎-p-hydroxyphenethyl-(7-methoxy-8-isoeugenol)-ferulate (11) inhibited the production and expression of nitric oxide (NO) in the LPS-induced BV2 cells in a concentration-dependent manner. Acorusnol (4), teucladiol (9), 7S⁎,8R⁎-benzyl-(7-methoxy-8-isoeugenol)-ferulate (12) and p-hydroxyphenethyl-(4-benzoy-3-methoxy)-cinnamate (13) only inhibited the release of NO at concentration of 20 µM. Moreover, 7S⁎,8R⁎-p-hydroxyphenethyl-(7-methoxy-8-isoeugenol)-ferulate (11) reduced the level of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in LPS-stimulated BV2 cells. The results demonstrated 7S⁎,8R⁎-p-hydroxyphenethyl-(7-methoxy-8-isoeugenol)-ferulate (11) could be a potential anti-neuroinflammatory agent and is worthy of further study.


Assuntos
Anti-Inflamatórios , Apiaceae , Compostos Fitoquímicos , Camundongos , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/isolamento & purificação , Estrutura Molecular , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Apiaceae/química , Linhagem Celular , Óxido Nítrico/metabolismo , China , Microglia/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química
18.
J Reprod Dev ; 59(5): 442-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23748715

RESUMO

The efficiency of cloning by somatic cell nuclear transfer (SCNT) has remained low. In most cloned embryos, epigenetic reprogramming is incomplete, and usually the genome is hypermethylated. The DNA methylation inhibitor 5-aza-2'-deoxycytidine (5-aza-dC) could improve the developmental competence of cow, pig, cat and human SCNT embryos in previous studies. However, the parameters of 5-aza-dC treatment among species are different, and whether 5-aza-dC could enhance the developmental competence of porcine cloned embryos has still not been well studied. Therefore, in this study, we treated porcine fetal fibroblasts (PFF) that then were used as donor nuclei for nuclear transfer or fibroblast-derived reconstructed embryos with 5-aza-dC, and the concentration- and time-dependent effects of 5-aza-dC on porcine cloned embryos were investigated by assessing pseudo-pronucleus formation, developmental potential and pluripotent gene expression of these reconstructed embryos. Our results showed that 5-aza-dC significantly reduced the DNA methylation level in PFF (0 nM vs. 10 nM vs. 25 nM vs. 50 nM, 58.70% vs. 37.37% vs. 45.43% vs. 39.53%, P<0.05), but did not improve the blastocyst rate of cloned embryos derived from these cells. Treating cloned embryos with 25 nM 5-aza-dC for 24 h significantly enhanced the blastocyst rate compared with that of the untreated group. Furthermore, treating cloned embryos, but not donor cells, significantly promoted pseudo-pronucleus formation at 4 h post activation (51% for cloned embryos treated, 34% for donor cells treated and 36% for control, respectively, P<0.05) and enhanced the expression levels of pluripotent genes (Oct4, Nanog and Sox2) up to those of in vitro fertilized embryos during embryo development. In conclusion, treating cloned embryos, but not donor cells, with 5-aza-dC enhanced the developmental competence of porcine cloned embryos by promotion of pseudo-pronucleus formation and improvement of pluripotent gene expression.


Assuntos
Azacitidina/análogos & derivados , Blastômeros/efeitos dos fármacos , Clonagem de Organismos/veterinária , Metilação de DNA/efeitos dos fármacos , Ectogênese/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Sus scrofa , Matadouros , Animais , Azacitidina/farmacologia , Blastocisto/efeitos dos fármacos , Blastocisto/enzimologia , Blastocisto/metabolismo , Blastômeros/enzimologia , Blastômeros/metabolismo , Células Cultivadas , DNA (Citosina-5-)-Metiltransferase 1 , DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , DNA (Citosina-5-)-Metiltransferases/metabolismo , Decitabina , Regulação para Baixo/efeitos dos fármacos , Técnicas de Cultura Embrionária/veterinária , Epigênese Genética/efeitos dos fármacos , Feminino , Feto/citologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Masculino , Técnicas de Transferência Nuclear/veterinária , RNA Mensageiro/metabolismo
19.
Chemosphere ; 291(Pt 2): 132954, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34800505

RESUMO

As a clean and efficient technology for the degradation of organic contaminants, sulfate radical based advanced oxidation processes (SR-AOPs) have attracted more and more attention in the past decades. Cobalt is regarded as the most reactive and efficient non-noble metal catalyst for the activation of persulfate including peroxymonosulfate (PMS) and peroxydisulfate (PDS) to produce sulfate radicals. Due to the limitations of homogeneous catalytic systems, the heterogeneous cobalt-containing catalysts have been emerged and rapidly developed. Various strategies have been schemed to further enhance the activation ability of persulfate by heterogeneous cobalt-containing catalysts. This paper provides an overview on the recent progress in enhancement strategies for the highly efficient activation of persulfate by heterogeneous cobalt-containing catalysts. With a brief introduction on the chemistry and feature of sulfate radical reactions catalyzed by homogeneous Co2+/Co3+ species, the main strategies for enhancing persulfate activation by heterogeneous cobalt-containing catalysts are summarized, such as surface and morphology design, multiple reactive centers design, organic-inorganic hybrids and heterostructure composites. Future perspectives of heterogeneous SR-AOPs systems catalyzed by cobalt-containing catalysts are outlined.


Assuntos
Cobalto , Metais , Catálise , Oxirredução
20.
Yi Chuan ; 33(7): 749-56, 2011 Jul.
Artigo em Zh | MEDLINE | ID: mdl-22049689

RESUMO

Uncompleted epigenetic reprogramming is attributed to the low efficiency of producing transgenic cloned animals. Histone modification associated with epigenetics can directly influence the embryo development and transgene expression. Trichostatin A (TSA), as an inhibitor of histone deacetylase, can change the status of histone acetylation, improve somatic cell reprogramming, and enhance cloning efficiency. TSA prevents the chromatin structure from being condensed, so that transcription factor could binds to DNA sequence easily and enhance transgene expression. Our study established the optimal TSA treatment on porcine donor cells and cloned embryos, 250 nmol/L, 24 h and 40 nmol/L, 24 h, respectively. Furthermore, we found that both the cloned embryo and the donor cell treated by TSA resulted in the highest development efficiency. Meanwhile, TSA can improve transgene expression in donor cell and cloned embryo. In summary, TSA can significantly improve porcine reconstructed embryo development and transgene expression.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , Suínos/embriologia , Suínos/genética , Transgenes/efeitos dos fármacos , Acetilação , Animais , Células Clonais , Clonagem de Organismos , Feminino , Masculino , Técnicas de Transferência Nuclear , Gravidez , Suínos/metabolismo
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