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1.
J Asian Nat Prod Res ; : 1-17, 2024 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-39317172

RESUMEN

As a kind of glycoside, pentacyclic triterpenoid saponins have good biological activities, such as anticancer, antibacterial, antiviral and hypoglycemic effects [1]. In this paper, twenty-four pentacyclic triterpenoid derivatives, including twelve monosaccharide derivatives, were designed and synthesized. The anticancer effect and antibacterial activities of all compounds were evaluated. It is noteworthy that compound UA-2b has the strongest inhibitory effect on the growth of A549, Hela and HepG2 cancer cells (IC50 = 5.37 ± 0.22 µM, 5.82 ± 0.25 µM and 5.47 ± 0.06 µM, respectively). Compounds OA-2b, OA-6a, OA-6b, UA-2b and UA-6a have the best activity against Escherichia coli 1924 (MIC = 16 µg/ml).

2.
J Asian Nat Prod Res ; 26(7): 812-823, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38477295

RESUMEN

Nineteen isosteviol derivatives were designed and synthesized by C-16, C-19 and D-ring modifications of isosteviol. These compounds were screened for their cytotoxic activities against Hela and A549 cells in vitro. Among them, the inhibitory effect of compounds 3b and 16 on Hela cells was comparable to that of the positive control gefitinib, and the compounds 3b (IC50=7.84 ± 0.84 µM) and 7a (IC50=6.89 ± 0.33 µM) exhibited significant cytotoxicity superior to gefitinib (IC50=11.02 ± 3.27 µM) against A549 cells.


Asunto(s)
Diterpenos de Tipo Kaurano , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Diterpenos de Tipo Kaurano/farmacología , Diterpenos de Tipo Kaurano/síntesis química , Diterpenos de Tipo Kaurano/química , Estructura Molecular , Células HeLa , Antineoplásicos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Células A549 , Gefitinib/farmacología , Relación Estructura-Actividad , Proliferación Celular/efectos de los fármacos , Quinazolinas/farmacología , Quinazolinas/química , Quinazolinas/síntesis química
3.
Hepatology ; 76(1): 66-77, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35007334

RESUMEN

BACKGROUND AND AIMS: The study objective was to compare the effectiveness of microwave ablation (MWA) and laparoscopic liver resection (LLR) on solitary 3-5-cm HCC over time. APPROACH AND RESULTS: From 2008 to 2019, 1289 patients from 12 hospitals were enrolled in this retrospective study. Diagnosis of all lesions were based on histopathology. Propensity score matching was used to balance all baseline variables between the two groups in 2008-2019 (n = 335 in each group) and 2014-2019 (n = 257 in each group) cohorts, respectively. For cohort 2008-2019, during a median follow-up of 35.8 months, there were no differences in overall survival (OS) between MWA and LLR (HR: 0.88, 95% CI 0.65-1.19, p = 0.420), and MWA was inferior to LLR regarding disease-free survival (DFS) (HR 1.36, 95% CI 1.05-1.75, p = 0.017). For cohort 2014-2019, there was comparable OS (HR 0.85, 95% CI 0.56-1.30, p = 0.460) and approached statistical significance for DFS (HR 1.33, 95% CI 0.98-1.82, p = 0.071) between MWA and LLR. Subgroup analyses showed comparable OS in 3.1-4.0-cm HCCs (HR 0.88, 95% CI 0.53-1.47, p = 0.630) and 4.1-5.0-cm HCCs (HR 0.77, 95% CI 0.37-1.60, p = 0.483) between two modalities. For both cohorts, MWA shared comparable major complications (both p > 0.05), shorter hospitalization, and lower cost to LLR (all p < 0.001). CONCLUSIONS: MWA might be a first-line alternative to LLR for solitary 3-5-cm HCC in selected patients with technical advances, especially for patients unsuitable for LLR.


Asunto(s)
Carcinoma Hepatocelular , Ablación por Catéter , Laparoscopía , Neoplasias Hepáticas , Carcinoma Hepatocelular/patología , Hepatectomía , Humanos , Neoplasias Hepáticas/patología , Microondas/uso terapéutico , Puntaje de Propensión , Estudios Retrospectivos , Resultado del Tratamiento
4.
Eur Radiol ; 33(10): 6781-6793, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37148350

RESUMEN

OBJECTIVES: This study evaluated the ability of a preoperative contrast-enhanced CT (CECT)-based radiomics nomogram to differentiate benign and malignant primary retroperitoneal tumors (PRT). METHODS: Images and data from 340 patients with pathologically confirmed PRT were randomly placed into training (n = 239) and validation sets (n = 101). Two radiologists independently analyzed all CT images and made measurements. Key characteristics were identified through least absolute shrinkage selection combined with four machine-learning classifiers (support vector machine, generalized linear model, random forest, and artificial neural network back propagation) to create a radiomics signature. Demographic data and CECT characteristics were analyzed to formulate a clinico-radiological model. Independent clinical variables were merged with the best-performing radiomics signature to develop a radiomics nomogram. The discrimination capacity and clinical value of three models were quantified by the area under the receiver operating characteristics (AUC), accuracy, and decision curve analysis. RESULTS: The radiomics nomogram was able to consistently differentiate between benign and malignant PRT in the training and validation datasets, with AUCs of 0.923 and 0.907, respectively. Decision curve analysis manifested that the nomogram achieved higher clinical net benefits than did separate use of the radiomics signature and clinico-radiological model. CONCLUSIONS: The preoperative nomogram is valuable for differentiating between benign and malignant PRT; it can also aid in treatment planning. KEY POINTS: • A noninvasive and accurate preoperative determination of benign and malignant PRT is crucial to identifying suitable treatments and predicting disease prognosis. • Associating the radiomics signature with clinical factors facilitates differentiation of malignant from benign PRT with improved diagnostic efficacy (AUC) and accuracy from 0.772 to 0.907 and from 0.723 to 0.842, respectively, compared with the clinico-radiological model alone. • For some PRT with anatomically special locations and when biopsy is extremely difficult and risky, a radiomics nomogram may provide a promising preoperative alternative for distinguishing benignity and malignancy.


Asunto(s)
Radiología , Neoplasias Retroperitoneales , Humanos , Neoplasias Retroperitoneales/diagnóstico por imagen , Nomogramas , Área Bajo la Curva , Tomografía Computarizada por Rayos X , Estudios Retrospectivos
5.
Phys Rev Lett ; 128(6): 060501, 2022 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-35213196

RESUMEN

As an important degree of freedom (d.o.f.) in photonic integrated circuits, the orthogonal transverse mode provides a promising and flexible way to increase communication capability, for both classical and quantum information processing. To construct large-scale on-chip multimode multi-d.o.f.s quantum systems, a transverse mode-encoded controlled-NOT (CNOT) gate is necessary. Here, with the help of our new transverse mode-dependent directional coupler and attenuator, we demonstrate the first multimode implementation of a 2-qubit quantum gate. The ability of the gate is demonstrated by entangling two separated transverse mode qubits with an average fidelity of 0.89±0.02 and the achievement of 10 standard deviations of violations in the quantum nonlocality verification. In addition, a fidelity of 0.82±0.01 is obtained from quantum process tomography used to completely characterize the CNOT gate. Our work paves the way for universal transverse mode-encoded quantum operations and large-scale multimode multi-d.o.f.s quantum systems.

6.
J Asian Nat Prod Res ; 24(8): 746-753, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35137660

RESUMEN

Two new stilbene glucosides, trans-3,5-dihydroxy-4-methoxystilbene 3-O-ß-D-glucopyranoside (1), cis-3,5-dihydroxy-4-methoxystilbene 3-O-ß-D-glucopyranoside (2), one new benzoic acid derivative, cis-4-hydroxy-3-hydroxymethyl-2-butenyl benzoate 4-O-ß-D-glucopyranoside (3), and four known compounds (4 - 7) were isolated from Tournefortia sibirica L. The structures of these compounds were elucidated on the basis of spectral data. Anti-inflammatory effects of compounds (1 - 7) were evaluated in terms of inhibition on production of NO, TNF-α and IL-6 in LPS-induced RAW 264.7 cells. Compounds 1, 2 and 5 - 7 could inhibit the levels of NO, TNF-α and IL-6 in LPS-induced RAW264.7 cells with IC50 values ranging from 40.96 to 88.76 µM.


Asunto(s)
Boraginaceae , Estilbenos , Ácido Benzoico/farmacología , Glucósidos/química , Glucósidos/farmacología , Interleucina-6 , Lipopolisacáridos/farmacología , Estructura Molecular , Estilbenos/química , Estilbenos/farmacología , Factor de Necrosis Tumoral alfa
7.
Phys Rev Lett ; 126(23): 230503, 2021 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-34170155

RESUMEN

Topological photonics has been introduced as a powerful platform for integrated optics, since it can deal with robust light transport, and be further extended to the quantum world. Strikingly, valley-contrasting physics in topological photonic structures contributes to valley-related edge states, their unidirectional coupling, and even valley-dependent wave division in topological junctions. Here, we design and fabricate nanophotonic topological harpoon-shaped beam splitters (HSBSs) based on 120-deg-bending interfaces and demonstrate the first on-chip valley-dependent quantum information process. Two-photon quantum interference, namely, Hong-Ou-Mandel interference with a high visibility of 0.956±0.006, is realized with our 50/50 HSBS, which is constructed by two topologically distinct domain walls. Cascading this kind of HSBS together, we also demonstrate a simple quantum photonic circuit and generation of a path-entangled state. Our work shows that the photonic valley state can be used in quantum information processing, and it is possible to realize more complex quantum circuits with valley-dependent photonic topological insulators, which provides a novel method for on-chip quantum information processing.

8.
Nano Lett ; 20(4): 2763-2769, 2020 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-32125868

RESUMEN

Developing efficient charge separation strategies is essential to achieve high-power conversion efficiency in the fields of chemistry, biology, and material science. Herein, we develop a facile strategy for fabrication of unique wafer-scale radial nanowire assemblies by exploiting shear force in rotary solution. The assembly mechanism can be well revealed by the large-scale stochastic dynamics simulation. Free electrons can be rapidly generated to produce quantitatively tunable current output when the radial nanowire assemblies rotate under the magnetic field. Moreover, the photoconductive performance of the radial semiconductor nanowire assemblies can be remarkably enhanced as the electron-hole recombination was retrained by the efficient charge separation under the rotating magnetic field. Such large-scale unique nanowire assemblies will facilitate the design of an efficient charge separation process in biosystem, sensors, and photocatalysis.


Asunto(s)
Nanocables/química , Semiconductores , Conductividad Eléctrica , Electrones , Diseño de Equipo , Campos Magnéticos , Procesos Estocásticos
9.
Nanotechnology ; 31(20): 205201, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-31952059

RESUMEN

We present a systematic study on the effects of CF4 plasma immersion ion implantation (PIII) in Si on the phase evolution of ultra-thin Ni silicides. For 3 nm Ni, NiSi2 was formed on Si substrates with and without CF4 PIII at temperature as low as 400 °C. For 6 nm Ni, NiSi was formed on pure Si, while epitaxial NiSi2 was obtained on CF4 PIII Si. The incorporation of C and F atoms in the thin epitaxial NiSi2 significantly reduces the layer resistivity. Increasing the Ni thickness to 8 nm results in the formation of NiSi, where the thermal stability of NiSi, the NiSi/Si interface and Schottky contacts are significantly improved with CF4 PIII. We suggest that the interface energy is lowered by the F and C dopants present in the layer and at the interface, leading to phase evolution of the thin Ni silicide.

10.
J Viral Hepat ; 26 Suppl 1: 85-89, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31380589

RESUMEN

BACKGROUND: The long-term administration of nucleotide analogues (NAs) and hepatitis B immune globulin (HBIG) comprises standard prophylaxis for patients with hepatitis B virus (HBV)-related liver diseases to prevent HBV reinfection after liver transplantation (LT). However, prolonging the prophylaxis strategy involves safety issues, such as the development of escape mutations and/or emerging resistant strains, and is also associated with high costs; further, it remains unclear how long prophylactic treatment should be continued. METHOD: Liver transplantation recipients responding to hepatitis B vaccination due to HBV-related liver diseases were retrospectively analysed after stopping HBIG and/or NAs, administered to prevent HBV reinfection, after long-term follow-up. The safety and effectiveness of the strategy were then evaluated for these responders. RESULT: Seventy-eight responders were enrolled. All responders discontinued HBIG, among which 36 stopped both HBIG and NAs. During follow-up, four recipients experienced HBV reinfection, which was associated with HBV escape mutations, after the withdrawal of both HBIG and NAs. No death or graft loss occurred in recipients during the follow-up period. CONCLUSION: A careful withdrawal of HBIG and/or NAs is feasible and safe for responders to hepatitis B vaccination receiving transplants for HBV-related liver diseases.


Asunto(s)
Vacunas contra Hepatitis B/administración & dosificación , Hepatitis B/prevención & control , Trasplante de Hígado , Privación de Tratamiento , Adulto , Anciano , Antivirales/administración & dosificación , Femenino , Estudios de Seguimiento , Hepatitis B/etiología , Vacunas contra Hepatitis B/inmunología , Humanos , Inmunoglobulinas/administración & dosificación , Trasplante de Hígado/efectos adversos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Factores de Tiempo
11.
Opt Express ; 27(20): 27991-28008, 2019 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-31684558

RESUMEN

In this paper, a kind of super-mode orbital angular momentum microstructured fiber (SM-OAM-MSF) is proposed. By introducing 20 Ge-doped equiangular cylindrical inclusions in the ring-core region, mode coupling mechanism is employed in the formation of super-OAM (SOAM) modes. Specifically, the double degenerated out-of-phase SMs are first generated by the coupling of individual core mode, then the quadruple degenerated SOAM modes are formed by combining two components of the out-of-phase SMs with a phase difference of ±π/2. Theoretical analysis and numerical results reveal that the effective index difference (Δneff) between adjacent out-of-phase SM groups are strongly influenced by the parameters of the individual core except the ring-core's width. Therefore, large mode area and SOAM modes' index separation larger than 1.0×10-4 can be achieved simultaneously in our proposed SM-OAM-MSF. Through careful fiber design, HE1,1 and HE2,1 are used in the formation of SMs and SOAM modes. Simulations show that all the nine SOAM groups originating from HE1,1 mode and the first five SOAM groups stemming from normal coupling of HE2,1 mode can be supported above 1.0µm, that are 56 SOAM modes in total. The highest purity is 99.86% for SOAM±2,1±,5 mode. And the maximum mode area (Aeff) value reaches up to 638.88µm2 at 1.55µm, which is nearly eight times larger compared to that of conventional ring-core MSFs.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2011-6, 2016 Jul.
Artículo en Zh | MEDLINE | ID: mdl-30035516

RESUMEN

Tapered microstructure fibers with different taper lengths and waist diameters are pumped with femtosecond laser for supercontinuum generation. With "fast and cold tapered method", home made microstructure fiber with air-hole pitch Λ=6.53 µm and normalized air-hole diameter d/Λ=0.79 were tapered to 6, 8, 10 mm taper length while keeping d/Λ unchanged. Numerical simulations show that the zero dispersion wavelength shifts to blue when the taper waist shrinks. The zero dispersion wavelengths for untapered and 6, 8, 10 mm length tapered fiber were 1 029, 885, 806, and 637 nm, respectively. In the experiment, 120 fs pulses centered at 810 nm, which is generated by mode-locked Ti:sapphire laser at a repetition rate of 76 MHz, is coupled into the tapered microstructure fiber. With the tapered length of 6 mm, the center wavelength of the pump light locates in the normal dispersion region of the fiber and near the zero dispersion wavelength of the tapered waist. The main factors causes spectra broaden are intrapulse Raman scattering and cascaded four-wave mixing. When the pump power reaches 450 mW, continuous spectra with -5 dB flatness are generated at 390~461 and 1 134~1 512 nm. With 500 mW pump power, supercontinuum spans from 366 to 2 450 nm, which has already covered ultraviolet, visible, near-infrared and mid-infrared. This broadband spectrum almost reaches the red and blue edges of the microstructure fiber's transmission bandwidth. With 8mm tapered length and 450 mW pump power, the blue edge of the continuous spectrum shifts down to 366 nm as a result of group velocity match and group acceleration mismatch, a 9 nm deeper blue shift compared to results from 6mm tapered length. With the tapered length of 10 mm, because the zero dispersion wavelength of the waist also moves to visible region, phase matching condition can still be satisfied in that region. Due to the effect of cascaded four-wave mixing, the frequency up conversion is realized in visible region. When pump power reaches 500mW, up conversion frequency lies in 30 nm band from 382 to 412 nm, the conversion efficiency is up to 27.7%.

13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(6): 1650-5, 2016 Jun.
Artículo en Zh | MEDLINE | ID: mdl-30052365

RESUMEN

Photonic crystal fiber can generate particular dispersion properties and highly nonlinear, because of the special guiding mechanism and the adjustable structure parameters,which provides new conditions for the study of nonlinear fiber optics. There are rich nonlinear spectral properties produced by a variety of nonlinear physical effect, under different pump light pulse parameters in photonic crystal fibers with different structure and transmission properties. At present many papers have reported the experimental results of nonlinear optical properties in photonic crystal fiber, but there is little theoretical analysis about the produced mechanism and the change rule of the nonlinear spectrum. In the paper, solving nonlinear Schrodinger equation with split-step Fourier method, transmission process of femtosecond laser pulse in photonic crystal fiber is simulated. The relationship between the output spectrum and incident light pulse parameters (the peak power of pump light P, the wavelength of pump light λ, the shape of light pulse, the width of light pulse TFWHM), the structure parameters of optical fiber (the pitch Λ, the hole-to-pitch ratio d/Λ, the length of fiber), the transmission characteristics (the dispersion properties, the nonlinear coefficient) is obtained. The spectral characteristics produced by nonlinear effects of the Raman soliton, dispersive wave, self-phase modulation are analyzed. The nonlinear optical spectrum of cladding note in photonic crystal fiber is studied in experiments, the broadband spectrum of soliton wave and dispersive wave is obtained. There are blue-shift dispersive wave near the wavelength of 0.5 µm, residual pump light near the wavelength of 0.82 µm, soliton wave near the wavelength of 1.1 µm, red-shift broadband dispersion wave near the wavelength of 2 µm in the spectrum obtained both in theory and experiment. The numerical simulation is confirmed through experimental observation. The physics principle of the nonlinear spectrum in photonic crystal fiber is revealed. These are useful and practical to realize the controllable output of broadband spectrum. These provide guidance for the structure design, fabrication, applied research of high nonlinear photonic crystal fiber.

14.
Exp Cell Res ; 319(3): 46-55, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23164508

RESUMEN

Cell research often requires combinational detection of RNA and DNA by fluorescence in situ hybridization (RNA-DNA FISH). However, it is difficult to preserve the fragile RNA signals through the harsh conditions used to denature the DNA template in DNA FISH. The current protocols of RNA-DNA FISH still cannot work robustly in all experiments. RNA-DNA FISH remains as a technically challenging and tedious experiment. By incorporating protein components into the signal detection steps of RNA FISH, which is then followed by a post-fixation step, we established an improved protocol of RNA-DNA FISH. The established method worked satisfyingly and robustly in our studies on Xist (inactivated X chromosome specific transcript) RNA and Terra (telomeric repeat-containing RNA). Our results provided the direct evidence to show that, not all the telomeres are associated with Terra, and a significant fraction of Terra foci do not overlap with telomere DNA in interphase cell nuclei. The improved method of simultaneous RNA-DNA FISH is reliable and time-efficient. It can be used in a variety of biological studies.


Asunto(s)
ADN/análisis , Hibridación Fluorescente in Situ/métodos , ARN/análisis , Procesamiento de Señales Asistido por Computador , Animales , Biotina/química , Biotina/metabolismo , Carbocianinas/química , Carbocianinas/farmacología , Células Cultivadas , ADN/metabolismo , Femenino , Técnica del Anticuerpo Fluorescente , Masculino , Ratones , Modelos Biológicos , Preservación Biológica/métodos , ARN/metabolismo , ARN Largo no Codificante/química , ARN Largo no Codificante/metabolismo , Manejo de Especímenes
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(6): 1460-4, 2014 Jun.
Artículo en Zh | MEDLINE | ID: mdl-25358145

RESUMEN

In the present paper, the four-wave mixing principle of fiber was analyzed, and the high-gain phase-matching conditions were shown. The nonlinear coefficient and dispersion characteristics of photonic crystal fibers were calculated by multipole method. The phase mismatch characteristics of fibers with multiple zero-dispersion wavelengths were analyzed for the first time. The changing rules of phase matching wavelength with the pump wavelength and the pump power were obtained, and the phase matching curves were shown. The characteristics of phase matching wavelengths for different dispersion curves were analyzed. There are four new excitation wavelengths of four-wave mixing spectrum in two zero-dispersion wavelength photonic crystal fiers. Four-wave mixing spectroscopy of photonic crystal fibers with two zero-dispersion wavelengths was obtained in the experi-ent, which is consistent with the theoretical analysis, and verified the reliability of the phase matching theory. The fiber with multiple zero-dispersion wavelengths can create a ricbhphase-matching topology, excite more four-wave mixing wavelengths, ena-ling enhanced control over the spectral locations of the four-wave mixing and resonant-radiation bands emitted by solitons and short pulses. These provide theoretical guidance for photonic crystal fiber wavelength conversion and supercontinoum generation based on four-wave mixing.

16.
Biochem Pharmacol ; 230(Pt 1): 116551, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39307317

RESUMEN

With the abuse of antibiotics, multidrug resistant strains continue to emerge and spread rapidly. Therefore, there is an urgent need to develop new antimicrobial drugs. As a highly conserved cell division protein in bacteria, filamenting temperature-sensitive mutant Z (FtsZ) has been identified as a potential antimicrobial target. This paper reviews the structure, function, and action mechanism of FtsZ and a variety of natural and synthetic compounds targeting FtsZ, including 3-MBA derivatives, taxane derivatives, cinnamaldehyde, curcumin, quinoline and quinazoline derivatives, aromatic compounds, purpurin, and totarol. From these studies, FtsZ has a clear supporting role in the field of antimicrobial drug discovery. The urgent need and interest of antibacterial drugs will contribute to the discovery of new clinical drugs targeting FtsZ.

17.
Huan Jing Ke Xue ; 45(7): 3839-3848, 2024 Jul 08.
Artículo en Zh | MEDLINE | ID: mdl-39022932

RESUMEN

In order to control the increasing ozone (O3) pollution in Hebi, Henan Province, clarifying the pollution characteristics of ozone and its precursors is vital. Therefore, we conducted a comprehensive analysis of O3 pollution utilizing the OFP-PMF-EKMA method combined with online hourly resolution monitoring data of conventional pollutants and volatile organic compounds (VOCs) in the summer of 2022 (June-September). Ozone formation potential (OFP) was used to identify the key VOCs species, and the PMF model was used to identify the VOCs emission sources, whereas EKMA curves and scenario analysis were used to identify the main ozone control area in Hebi and to determine the reduction ratio of VOCs and NOx in a scientifically refined way. In 2022, Hebi had persistent O3 pollution, with the highest concentration in June. Conditions of high temperature, low humidity, and low atmospheric pressure contributed to the O3 accumulation. Aromatic and oxygenated volatile organic compounds (OVOCs) contributed significantly to the OFP and VOCs fraction, which were the dominant active substance and concentration dominant species. The results of the VOCs source analysis indicated that vehicle exhaust sources (25.3%) were the main source of atmospheric VOCs, followed by process sources (17.7%) and biomass combustion sources (17.6%). Thus, emission sources associated with the combustion of fossil fuels and industrial production emissions were the most urgent sources of atmospheric VOCs to be controlled in Hebi. The O3 generation in Hebi occurred in the VOCs-sensitive zones, and the emission reduction results showed that a synergistic emission reduction of VOCs and nitrogen oxide (NOx) could effectively control O3 pollution with a 75% reduction in VOCs and a 10% reduction in NOx.

18.
Huan Jing Ke Xue ; 44(8): 4728-4741, 2023 Aug 08.
Artículo en Zh | MEDLINE | ID: mdl-37694665

RESUMEN

The extensive application of plastic products leads to the increasingly significant harm of plastic wastes to the ecological environment, which is also a focus of global environmental issues. Due to the lack of a sound plastic waste management system, most plastic waste is still treated by the traditional mode or remains in the environment, with low recycling efficiency, and the plastic life cycle has not yet formed. Plastics in the environment will age and degrade under the actions of physical (wear, waves), chemical (ultraviolet radiation, hydrolysis), and biological (fungi, bacteria) factors for a long time and generate micro (nano) plastics. Due to their small particle size, large specific surface area, and charged characteristics, in addition to their own toxicity, they can also be used as carriers or covert carriers of pollutants (heavy metals, persistent organic pollutants, polycyclic aromatic hydrocarbons, bacteria, etc.) to migrate in the environment through runoff, sewage discharge, and hydrometeorology, causing ecological environmental pollution. MPs pollution has been listed as the second largest scientific problem in the field of environmental and ecological science by the United Nations Environment Programme. MPs are widely distributed, and there are different degrees of MPs pollution in the global water (freshwater, ocean), soil, and atmospheric environment. Traces of MPs have also been found in human placentas, human breastmilk, living lungs, and blood in recent years. Therefore, the formation mechanisms of MPs under the actions of physics, chemistry, and microorganisms, as well as their abundance levels and migration characteristics in water, soil, and atmosphere environment were comprehensively reviewed, with the hope of providing reference for monitoring the pollution levels of MPs in the environment, exploring their transport laws in the environment, proposing the management strategy of MPs pollution, and revealing the degradation mechanisms of MPs under different effects.


Asunto(s)
Microplásticos , Plásticos , Humanos , Femenino , Embarazo , Rayos Ultravioleta , Atmósfera , Ambiente
19.
Acta Biomater ; 157: 467-486, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36460288

RESUMEN

Diabetic wounds are challenging to heal due to complex pathogenic abnormalities. Routine treatment with acid fibroblast growth factor (aFGF) is widely used for diabetic wounds but hardly offers a satisfying outcome due to its instability. Despite the emergence of various nanoparticle-based protein delivery approaches, it remains challenging to engineer a versatile delivery system capable of enhancing protein stability without the need for complex preparation. Herein, a polyphenol-driven facile assembly of nanosized coacervates (AE-NPs) composed of aFGF and Epigallocatechin-3-gallate (EGCG) was constructed and applied in the healing of diabetic wounds. First, the binding patterns of EGCG and aFGF were predicted by molecular docking analysis. Then, the characterizations demonstrated that AE-NPs displayed higher stability in hostile conditions than free aFGF by enhancing the binding activity of aFGF to cell surface receptors. Meanwhile, the AE-NPs also had a powerful ability to scavenge reactive oxygen species (ROS) and promote angiogenesis, which significantly accelerated full-thickness excisional wound healing in diabetic mice. Besides, the AE-NPs suppressed the early scar formation by improving collagen remodeling and the mechanism was associated with the TGF-ß/Smad signaling pathway. Conclusively, AE-NPs might be a potential and facile strategy for stabilizing protein drugs and achieving the scar-free healing of diabetic wounds. STATEMENT OF SIGNIFICANCE: Diabetic chronic wound is among the serious complications of diabetes that eventually cause the amputation of limbs. Herein, a polyphenol-driven facile assembly of nanosized coacervates (AE-NPs) composed of aFGF and EGCG was constructed. The EGCG not only acted as a carrier but also possessed a therapeutic effect of ROS scavenging. The AE-NPs enhanced the binding activity of aFGF to cell surface receptors on the cell surface, which improved the stability of aFGF in hostile conditions. Moreover, AE-NPs significantly accelerated wound healing and improved collagen remodeling by regulating the TGF-ß/Smad signaling pathway. Our results bring new insights into the field of polyphenol-containing nanoparticles, showing their potential as drug delivery systems of macromolecules to treat diabetic wounds.


Asunto(s)
Diabetes Mellitus Experimental , Ratones , Animales , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Factor 1 de Crecimiento de Fibroblastos/farmacología , Simulación del Acoplamiento Molecular , Especies Reactivas de Oxígeno , Cicatrización de Heridas , Cicatriz , Colágeno/farmacología , Factor de Crecimiento Transformador beta/farmacología
20.
Zhonghua Gan Zang Bing Za Zhi ; 20(6): 468-71, 2012 Jun.
Artículo en Zh | MEDLINE | ID: mdl-23044207

RESUMEN

To identify the integration sites in the host genome for the hepatitis B virus (HBV)-encoded X protein (HBx) in hepatocellular carcinoma (HCC) biopsies that are positive for hepatitis B surface antigen (HBsAg). HCC biopsies were obtained from six patients that were HBV carriers, as demonstrated by the presence of HBsAg in their serum and sero-negativity for antibody to HBsAg. DNA was extracted from the tissue, fractionated, and circularized. Primers were designed according to the HBx sequence and used to amplify the circularized DNA templates by inverse polymerase chain reaction (IPCR). The amplified DNA fragments were checked by electrophoresis, cloned into the PMD18-T expression vector, and sequenced. Sequence alignment was performed by the Blast algorithms. Seven electrophoresis bands yielded 22 sequencing results, which represented a total of three HBx integration sites in the host genome: 19q12, 2q32.2, 22q12. The 19q12 integration site encompasses the CCNE1 gene, which encodes a G1/S-specific cyclin-E1. HBx-related integration sites exist in HBsAg-positive HCC biopsies. The CCNE1 gene may play a role in the development of HBx-related HCC.


Asunto(s)
Carcinoma Hepatocelular/genética , Virus de la Hepatitis B/fisiología , Neoplasias Hepáticas/genética , Transactivadores/genética , Integración Viral , Carcinoma Hepatocelular/sangre , Ciclina E/genética , Cartilla de ADN , ADN Viral/genética , Antígenos de Superficie de la Hepatitis B/metabolismo , Virus de la Hepatitis B/genética , Humanos , Neoplasias Hepáticas/sangre , Proteínas Oncogénicas/genética , Proteínas Reguladoras y Accesorias Virales
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