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1.
Animals (Basel) ; 11(3)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668322

RESUMO

This study aimed to investigate the effect of the fermented soybean meal on the reproductive performance, oxidative stress and colostrum composition of sows, and the growth performance of their progeny. A total of 44 sows were allotted to four dietary groups (n = 11/group). The dietary groups included the basal diet group (control) and the treatment groups in which soybean meal in the basal diet was replaced with 2%, 4%, and 6% fermented soybean meal, respectively. The experimental diets were fed to the sows from the 78th day of gestation to the 21st day of lactation. Replacing soybean meal in the basal maternal diet with the fermented soybean meal decreased the levels of malondialdehyde, cortisol, and 8-iso-prostaglandinF2α in the serum of sows and increased the average weight of piglets on the 14th day and the 21st day after birth. The activity of superoxide dismutase in the serum of sows was increased in the group with 4% fermented soybean meal on the 17th day of lactation. The levels of estrogen and growth factors in the serum of sows were enhanced in the group with 6% fermented soybean meal. In the colostrum, the levels of the protein and the immunoglobulin G were enhanced in the group with 4% fermented soybean meal. In conclusion, replacing the soybean meal in the basal maternal diet with the fermented soybean meal attenuates the oxidative stress status of the gestational and lactational sows, and enhances the average weight of their offspring.

2.
J Biomed Nanotechnol ; 17(2): 312-321, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33785101

RESUMO

The establishment of sensing platform for trace analysis of Fe3+ in biological systems is meaningful for health monitoring. Herein, a Fe3+ sensitive fluorescent nanoprobe was constructed based on highly fluorescent N-doped carbon quantum dots (NCQDs) derived from bamboo stems through a hydrothermal method employing ethylenediamine as the nitrogen dopant. The prepared NCQDs had a uniformly distributed size and their mean size was around 2.43 nm. Abundant functional groups (C=N, N-H, C=O, and carboxyl) anchored on NCQDs demonstrated successful doping of N in CQDs. The obtained NCQDs possessed a high fluorescence quantum yield of 20.02% and outstanding fluorescence stability over a wide pH range and at high ionic strengths. Moreover, Fe3+ ions presented a specific fluorescent quenching effect to the as-prepared NCQDs. The calibration curve for fluorescence quenching degree corresponding to Fe3+ concentration showed a linear response in a range of 0.01-10 µM, and detection limit was 0.486 µM, which indicated that the NCQDs had high sensitivity to Fe3+ ions. Ascribed to these unique properties, the NCQDs were selected as luminescent probes for trace amount of Fe3+ ions in human serum. These results demonstrated their promising use in clinical diagnostics and other biologically relevant studies.


Assuntos
Pontos Quânticos , Carbono , Corantes Fluorescentes , Humanos , Íons , Nitrogênio , Espectrometria de Fluorescência
3.
Chemosphere ; 276: 130138, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33740647

RESUMO

Three different visible-light photocatalysts (hematite (α-Fe2O3), bismuth vanadate (BiVO4) and Mo-doped bismuth vanadate (BiMoVO4)) deposited on transparent fluorine-doped SnO2 (FTO) were evaluated for the solar-driven photoelectrocatalytic treatment of emerging pollutants. BiMoVO4 was found to be the most effective photoanode, yielding the fastest degradation rate constant and highest mineralization efficiency using phenol as the oxidation probe. The BiMoVO4 photoanode was then used to degrade the herbicide simazine in a photoelectrolytic cell combining photoelectrocatalysis (PEC) with photoelectron-Fenton (PEF) under solar light (SPEC-SPEC). Total simazine removal was achieved within 1 min of treatment (kapp = 4.21 min-1) at the optimum electrode potential of 2.5 V vs Ag/AgCl, with complete TOC removal in 2 h. The analysis of anionic species in solution during treatment showed that most of the nitrogen heteroatoms in the simazine structure were converted into NO3- following •OH addition to organic N. This innovative process combining BiMoVO4-PEC with PEF using solar light as a sustainable source of energy (SPEC-SPEF) achieved the highest degradation/mineralization efficiency ever reported for simazine treatment. Besides, this is the first work reporting the photo(electrochemical) degradation of this toxic herbicide.

4.
Artigo em Inglês | MEDLINE | ID: mdl-33401757

RESUMO

(1) Background: Assignment of pathogens to the correct genus, species, and type is vital for controlling infectious epidemics. However, the role of different enteroviruses during hand, foot, and mouth disease (HFMD) epidemics and the major contributing factors remain unknown. (2) Methods: HFMD cases from 2016 to 2018 in Guangzhou, China were collected. The relationship between HFMD cases and genotype frequency, as well as the association between genotype frequency and climate factors, were studied using general linear models. We transformed the genotype frequency to the isometric log-ratio (ILR) components included in the model. Additionally, vaccination rates were adjusted in the climate-driven models. (3) Results: We observed seasonal trends in HFMD cases, genotype frequency, and climate factors. The model regressing case numbers on genotype frequency revealed negative associations with both the ILRs of CAV16 (RR = 0.725, p < 0.001) and EV71 (RR = 0.421, p < 0.001). The model regressing genotype frequency on driven factors showed that the trends for EV71 proportions were inversely related to vaccination rate (%, ß = -0.152, p = 0.098) and temperature (°C, ß = -0.065, p = 0.004). Additionally, the trends for CVA16 proportions were inversely related to vaccination rate (%, ß = -0.461, p = 0.004) and temperature (°C, ß = -0.068, p = 0.031). The overall trends for genotype frequency showed that EV71 decreased significantly, while the trends for CVA16 increased annually. (4) Conclusions: Our findings suggest a potential pathway for climate factors, genotype frequency, and HFMD cases. Our study is practical and useful for targeted prevention and control, and provides environmental-based evidence.


Assuntos
Clima , Infecções por Enterovirus/epidemiologia , Infecções por Enterovirus/virologia , Enterovirus/genética , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/virologia , Vacinação/estatística & dados numéricos , China/epidemiologia , Feminino , Genótipo , Humanos , Modelos Lineares , Masculino , Filogenia , Vigilância da População , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Nutrition ; 81: 110940, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32755743

RESUMO

OBJECTIVES: The aim of the present study was to investigate the potential of pterostilbene, a beneficial component primarily found in blueberries, to alleviate the intrauterine growth retardation (IUGR)-induced early liver injury and oxidative stress in a porcine model. METHODS: Thirty-six IUGR piglets and an equal number of normal birth weight (NBW) counterparts received a diet with or without pterostilbene (250 mg/kg diet) during the first week post-weaning. Parameters related to the hepatic injury, oxidative stress, and antioxidant defense mechanisms were analyzed. RESULTS: Relative to NBW, IUGR induced liver injury, which corresponded to increments in circulating alanine transaminase activity and hepatic apoptotic cell rate, superoxide radical generation, and the accumulation of oxidative damage products (P < 0.05). Administering pterostilbene reduced plasma transaminase activities, decreased hepatocyte apoptosis rate, and prevented the augmented levels of hepatic superoxide anion, 8-hydroxy-2 deoxyguanosine, and 4-hydroxynonenal-modified protein (P < 0.05). In terms of the hepatic antioxidant function, pterostilbene was efficient in improving the superoxide dismutase activity and the metabolic cycle between reduced glutathione and its oxidized form (P < 0.05). The pterostilbene-supplemented diet facilitated the nuclear translocation of nuclear factor erythroid-2-related factor 2 (NRF2) and promoted the expression levels of superoxide dismutase 2 in the liver of IUGR piglets (P < 0.05). CONCLUSION: This study indicates that pterostilbene treatment has an auxiliary therapeutic potential to ameliorate early liver injury in IUGR neonates, presumably by stimulating the NRF2 signals and the associated antioxidant function.

6.
J Hazard Mater ; 402: 123359, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-32738779

RESUMO

Both secondary pollution and the low mechanical strength of adsorbents have severely impeded the practical application of adsorption methods in the dye wastewater treatment. In this work, we innovatively synthesized a composite hydrogel adsorbent by incorporating polydopamine (PDA) and montmorillonite (MMT) into the pullulan hydrogel matrix for dye adsorption. First, the successful formation of the resultant adsorbents was verified by Fourier-transform infrared spectroscopy and scanning electron microscope elemental mapping analysis. Then, several physicochemical properties (such as thermal and swelling properties, microarchitecture, and mechanical strength) of the five prepared adsorbents (PM1-PM5) were investigated. These results demonstrated the adsorbents had tunable properties, which can be achieved by adjusting the PDA/MMT mass ratio. Next, the dye adsorption performance was systematically explored. The resultant adsorbent (PM3) had a maximum adsorption capacity of 112.45 mg/g and its adsorption data was best described by a Langmuir isotherm and pseudo-second-order kinetic. Finally, the adsorption mechanisms and potential commercial practicability of the adsorbent were studied. Altogether, the designed adsorbent could effectively avoid generating the secondary pollution typical of adsorbents and it displayed excellent mechanical strength, thus opening up a new horizon in mitigating environmental pollution from textile industries.

7.
Biomaterials ; 265: 120392, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32992116

RESUMO

The large-scale utilization of nanotechnology depends on public and consumer confidence in the safety of this new technology. Studying the interaction of nanoparticles with immune cells plays a vital role in the safety assessment of nanomedicine. Although some researches have indicated that the immune cells undergo severe interfere after phagocytosis of nanoparticles, the impact on immune system of the whole body are still unclear. Here, we use immune cells labeled transgenic zebrafish to study the mechanisms of nanoparticles on zebrafish immune cells. We demonstrate that gold nanoparticles (Au NPs) phagocytized by immune cells can reduce and retard the sensitivity of immune response, resulting nanoparticle-induced bluntness in immune cell (NIBIC). RNA-seq and functional analysis reveal that NIBIC is mainly induced by the inhibiting expression of chemokine receptor 5 (CCR5). Furthermore, PVP-modified Au NPs can eliminate NIBIC by inhibiting the cell phagocytosis. Our results highlight the potential risk for Au NPs in vivo and further the understanding of the mechanism of the interaction between Au NPs and the immune response. We should consider this factor in future material design and pay more attention to the process of using nanomedicines on immune diseases.

8.
Front Chem ; 8: 599981, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33282842

RESUMO

Hierarchically nanoporous carbon materials (HNCMs) with well-defined morphology and excellent electrochemical properties are promising in fabrication of energy storage devices. In this work, we made a comparative study on the supercapacitive performances of HNCMs with different morphologies. To this end, four types of HNCMs with well-defined morphologies including submicrospheres (HNCMs-S), hexagonal nanoplates (HNCMs-N), dumbbell-like particles (HNCMs-D), and hexagonal microprisms (HNCMs-P) were successfully synthesized by dual-template strategy. The relationship of structural-electrochemical property was revealed by comparing the electrochemical performances of these HNCMs-based electrodes using a three-electrode system. The results demonstrated that the HNCMs-S-based electrode exhibited the highest specific capacitance of 233.8 F g-1 at the current density of 1 A g-1 due to the large surface area and well-defined hierarchically nanoporous structure. Moreover, the as-prepared HNCMs were further fabricated into symmetrical supercapacitor devices (HNCMs-X//HNCMs-X) using KOH as the electrolyte and their supercapacitive performances were checked. Notably, the assembled HNCMs-S//HNCMs-S symmetric supercapacitors displayed superior supercapacitive performances including high specific capacitance of 55.5 F g-1 at 0.5 A g-1, good rate capability (retained 71.9% even at 20 A g-1), high energy density of 7.7 Wh kg-1 at a power density of 250 W kg-1, and excellent cycle stability after 10,000 cycles at 1 A g-1. These results further revealed the promising prospects of the prepared HNCMs-S for high-performance energy storage devices.

9.
Animals (Basel) ; 10(9)2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32825099

RESUMO

The aim of this study is to investigate the effect of the maternal diet with fish oil on the oxidative stress and inflammatory response in sows, and the protective effect on the piglets suckling the sows fed the diet with fish oil in the context of inflammatory stimulation. Twelve sows were divided into two groups. Sows were fed soybean oil diet (SD) or soybean oil + fish oil diet (FD) from gestation to lactation period. The blood samples of sows were collected from the auricular vein at the 16th day of lactation. One piglet was selected from each litter on the 14th day after birth. Lipopolysaccharide (LPS) was injected into the neck muscle after pre-treatment blood samples were collected from the anterior vena cava of piglets. The blood samples of piglets were collected at 5 h and 48 h post-LPS injection from the front cavity vein. Liver samples were collected at 48 h post-LPS injection. The FD diet significantly increased the level of high-density lipoprotein cholesterol (HDL-C) in the plasma of lactating sow, decreased the levels of alkaline phosphatase(AKP) and tumor necrosis factor alpha(TNF-α) in the plasma of lactating sows, and increased the level of immunoglobulin G(IgG) in the colostrum and interleukin-10(IL-10) in the milk (p < 0.05). In the FD group, the levels of glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) significantly increased in the plasma of piglets at 48 h post-LPS injection (p < 0.05). Meanwhile, the relative expression of GSH-Px mRNA was decreased in the FD group (p < 0.05). However, the levels of interleukin-1 beta (IL-1ß) and interleukin-6(IL-6) in the plasma of piglets were significantly higher in the FD group pre- and post-LPS injection (p < 0.05). The ratio of the phosphonated extracellular regulated protein kinases to the extracellular regulated protein kinases (p-ERK/ERK) protein in the livers of piglets was decreased (p < 0.05), but the expression of nuclear transcription factor-κB (NF-κB) mRNA and the ratio of the phosphonated inhibitor of NF-κB to the inhibitor of NF-κB (p-IκB-α/IκB-α) protein was increased in the livers of piglets (p < 0.05). These results indicate that a maternal diet with fish oil might decrease the oxidative stress and inflammatory response in sows, and enhance the antioxidative ability but increase the susceptibility to inflammatory stimulation in their progenies.

10.
Int J Infect Dis ; 99: 149-155, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32795602

RESUMO

BACKGROUND: The DTaP-IPV/Hib combination vaccine can replace the acellular tetanus vaccine, polio vaccine, and the Haemophilus influenzae type B vaccine. Data on the safety of DTaP-IPV/Hib vaccines are required. We aimed to evaluate the safety of the vaccination program. METHODS: Using the National Adverse Events Following Immunization (AEFI) surveillance system (CNAEFIS) in Guangzhou, China, a retrospective study was performed from May 11, 2011, to December 31, 2017. There were 376 cases of adverse events after vaccination with the DTaP IPV/Hib vaccine. The primary analysis indicators were the number of vaccines used, the number of AEFI reports received, and the reporting rate (per 100,000). RESULTS: From May 1, 2011, to December 31, 2017, 516,000 doses of vaccine were inoculated, and 376 cases of adverse reactions were reported; the reporting rate was 72.8 per 100,000 vaccines. There were eight cases of serious AEFIs (1.5 per 100,000), with four cases of thrombocytopenic purpura (0.8 per 100,000); three cases of cyanosis of the lips, stiffness, and flexion of limbs, and convulsions (0.6 per 100,000); and one case of a high fever (0.2 per 100,000). The highest incidence of AEFIs occurred after the fourth dose (n = 207, 55.0%, 40.1 per 100,000), followed by the first dose (n = 81, 21.5%, 15.7 per 100,000), second dose (n = 48, 12.8%, 9.3 per 100,000) and third dose (n = 40, 10.6%, 7.7 per 100,000). The AEFI incidence was higher after injection of the vaccine into the deltoid muscle of the upper arm (n = 276, 73.4%, 53.5 per 100,000) than after injection of the vaccine into the thigh (n = 100, 26.6%, 19.4 per 100,000). There was a significant difference between AEFIs after injection into the deltoid of the upper arm deltoid and the thigh (x2 = 164.8, P < 0.05). CONCLUSIONS: Most of the reported AEFIs after DTaP-IPV/Hib vaccination are not serious. There were four cases of TP in this study; vaccination may be a rare cause of thrombocytopenic purpura.

11.
J Mater Chem B ; 8(27): 5952-5961, 2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32667025

RESUMO

Rational design and fabrication of bio-nanoprobes for intracellular miRNA biosensing are highly desired for early clinical diagnosis and prognosis. Herein, we have developed a versatile LRET-based ratiometric (LBRU) nanoprobe of NaYF4:Yb,Er@NaYF4@NH2-mSiO2/rhodamine B/C-DNA sandwich-structured nanocomposites for intracellular miRNA biosensing. The nanoprobe was composed of NaYF4:Yb,Er@NaYF4 upconversion nanoparticles (energy donor) with an amino functionalized mesoporous silica shell (NH2-mSiO2), rhodamine B (acceptor) loaded into the mesopores of NH2-mSiO2, and the complementary sequences of target miRNA (denoted as C-DNA) acting as recognition species wrapped on the nanocomposite. Due to the LRET behavior between donors and acceptors, the loaded rhodamine B can quench the green upconversion emission of NaYF4:Yb,Er@NaYF4 at 540 nm completely. Moreover, it can be released from the nanocomposite in the presence of target miRNA, which blocked the LRET behavior to "turn on" the green upconversion luminescence. Besides, as the unaffected red upconversion luminescence (at 660 nm) can be used as an internal standard to provide built-in correction for environmental effects, the intensity ratio of upconversion luminescence at 540 and 660 nm (I540/I660) was employed as the output signal to afford an accurate detection of target miRNA. Due to the biocompatibility, high photostability and low auto-fluorescence background, the nanoprobe was successfully utilized to diagnose the intracellular miRNA-21 expression in MCF-7 cells via upconversion fluorescence imaging. We envision that the proposed LBRU nanoprobe has great potential applications in early cancer diagnosis.

12.
Hum Vaccin Immunother ; : 1-7, 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32530733

RESUMO

OBJECTIVE: Hand, foot, and mouth disease (HFMD) is an important public health issue in China. Although efficacy has been demonstrated by randomized controlled trials, the evidence for effectiveness of the monovalent Enterovirus 71 (EV71) vaccine against HFMD remains unknown. This study aimed to assess the vaccine effectiveness for HFMD in Guangzhou, China. METHODS: Routinely collected vaccination and HFMD surveillance data were captured from the China Information System for Disease Control and Prevention. We estimated the EV71 vaccine effectiveness using spatial ecologic and time-series analysis approaches. RESULTS: A total of 174,002 HFMD cases under 5 years of age were reported to the Guangzhou, China surveillance system from January 2016 to December 2018. A total of 408,664 children completed a two-dose EV71 vaccination series. In an ecologic analysis, a two-dose EV71 vaccination rate above the median conferred lower HFMD risk relative to a vaccination rate below the median (ratio ratio = 0.955, 95% confidence interval (CI): 0.949, 0.962; P < .001). In the time-series approach, 0.9% fewer HFMD cases were associated with a 1% increase in the two-dose EV71 vaccination rate, but without statistical significance (P = .094). However, we detected statistically significant protective associations for HFMD among children 3 years of age (0.9% fewer HFMD cases with a 1% increased vaccination rate; P = .046), and for EV71 (1.4%; P = .012) and "other viruses" (1.3%; P = .002), although not for Coxsackievirus A16 (CVA16). CONCLUSION: Our findings, based on real-world data, provide evidence of EV71 vaccine effectiveness for preventing EV71 and "other" viruses associated with HFMD. An expanded program of EV71 vaccination is urgently needed.

13.
Food Funct ; 11(5): 4202-4215, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32352466

RESUMO

This study investigated the potential of resveratrol (RSV) and its derivative pterostilbene (PT) to prevent diquat (DQ)-induced hepatic oxidative damage and mitochondrial dysfunction in piglets. Seventy-two weanling piglets were randomly divided into the following treatment groups: non-challenged control group, DQ-challenged control group, and DQ-challenged groups supplemented with either 300 mg RSV per kg of diet or an equivalent amount of PT. Each treatment group consisted of six replicates with three piglets per replicate (n = 6). After a two-week feeding trial, piglets were intraperitoneally injected with either 10 mg DQ per kg of body weight or sterile saline. At 24 hours post-injection, one piglet from each replicate (six piglets per treatment) was randomly selected for sample collection and biochemical analysis. Compared with the DQ-challenged control group, PT attenuated the growth loss of piglets after the DQ challenge (P < 0.05). Administration of PT was more effective than its parent compound in inhibiting the DQ-induced hepatic apoptosis and the increased generation of total cholesterol, superoxide anion, and lipid peroxidation products (P < 0.05). Specifically, PT facilitated nuclear factor erythroid 2-related factor 2 signals and the expression and activity of manganese superoxide dismutase, while it also prevented mitochondrial swelling, membrane potential collapse, and adenosine triphosphate depletion, possibly through the activation of sirtuin 1 (P < 0.05). These results indicate that PT may be superior to RSV as an antioxidant to protect the liver of young piglets from oxidative insults.

14.
Fish Shellfish Immunol ; 102: 336-349, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32360278

RESUMO

The study investigated whether dietary berberine supplementation could improve intestinal barrier against inflammation induced by high-fat and high-carbohydrate diets in blunt snout bream. Fish (average initial weight 44.83 ± 0.06 g) were fed with six kinds of diets (control, high-fat diet (10% lipid) and high-carbohydrate (43% nitrogen-free extract) diet, control/berberine, high-fat/berberine or high-carbohydrate/berberine) for 8 weeks, respectively. Feeding mode of berberine (50 mg/kg diet) was adopted to two-week interval. After feeding trial, fish growth performance and intestinal barrier function were estimated. The result showed that no significant interactions between diet and berberine in growth performance, whole body composition or protein utilization were observed (P > 0.05). Specific growth rate (SGR) and feed conversion ratio (FCR) were significantly affected by berberine (P < 0.05). Protein efficiency ratio (PER), nitrogen retention (NRE), fish whole-body lipid contents increased greatly in high-fat or high-carbohydrate diets (P < 0.05). Significant interactions between diet and berberine were observed in fish intestinal barrier (physical, chemical, immunological and microbiological barriers) (P < 0.05). High-fat and high-carbohydrate diets could increase significantly intestinal permeability and inflammatory response, decrease intestinal mucins gene expression levels, and make the intestinal microbiota out of balance (P < 0.05). Berberine significantly inhibited inflammation response and modulated intestinal microflora profile (P < 0.05). Taken together, berberine could alleviate intestinal barrier damage injured by high-fat or high-carbohydrate diet and improve the growth performance of blunt snout bream.

15.
Theranostics ; 10(5): 2374-2384, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32089746

RESUMO

Liquid biopsy has emerged in the last ten years as an appealing noninvasive strategy to support early cancer diagnosis and follow-up interventions. However, conventional liquid biopsy strategies involving specified biomarkers have encountered unexpected inconsistencies stemming from the use of different analytical methodologies. Recent reports have repeatedly demonstrated that integrated detection of multiple liquid biopsy biomarkers can significantly improve diagnostic performance by eliminating the influence of intratumoral heterogeneity. Herein, we review the progress in the field of liquid biopsy and propose a novel integrated liquid biopsy framework consisting of three categories: elementary, intermediate, and advanced integration. We also summarize the merits of the integration strategy and propose a roadmap toward refining cancer diagnosis, metastasis surveillance, and prognostication.

16.
Int J Biol Macromol ; 145: 1049-1058, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31759765

RESUMO

Designing a new adsorbent with recyclability, high efficiency and biodegradability is important for treating heavy metals contamination but remains a severe challenge. In this work, a novel type of hydrogel biosorbents based on pullulan and polydopamine were designed for heavy metal ions removal from aqueous solution. The physicochemical properties of the prepared pullulan/polydopamine (Pu/PDA) hydrogels were fully characterized by thermal gravimetric analysis, Fourier transform infrared spectroscopy, rheology, scanning electron microscopy, swelling and compression tests. We observed that their mechanical strength, pore size, water absorption and retention properties could be nicely controlled by adjusting the PDA concentration in the pre-gel solution. Subsequently, the adsorption ability of designed Pu/PDA hydrogels to Cu2+, Co2+ and Ni2+ was investigated in detail. These hydrogels presented excellent adsorption capability for heavy metal ions and matched well with the pseudo-second-order kinetic model and Freundlich isotherm model. Overall, having tunable physicochemical properties coupled with the high absorption ability for heavy metal ions, these Pu/PDA hydrogels may be a promising strategy for removal of pollutants from aqueous solution.

17.
J Nanosci Nanotechnol ; 20(3): 1511-1519, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492314

RESUMO

Recently, lanthanide-doped upconversion luminescent materials have showed great potential in optical data storage, information encryption and anti-counterfeiting. However, the low upconversion luminescence still limited their applications. In this work, we fabricated RGB NaYF4:Ln3+@NaYF4 core-shell nanoparticles (CSNPs) with enhanced upconversion luminescence by coating an inert NaYF4 shell onto NaYF4:Ln3+ core nanoparticles via thermal decomposition method. The effect of increased shell temperature and addition of shell precursors on crystal phase, morphology and luminescent property of the synthesized CSNPs were systematically investigated. It was demonstrated that high shell growing temperature facilitated the formation of pure ß-NaYF4 CSNPs. Upon increasing amount of shell precursors, the morphologies of hexagonal phase NaYF4 CSNPs changed from nanorod to nanocube and showed different luminescent properties. Pure hexagonal phase NaYF4 CSNPs with highest upconversion luminescence of about 15 times higher than NaYF4:Ln3+ core nanoparticles can be prepared at 310 °C with the addition of shell precursors at 3 mmol. Moreover, three-primary-color (RGB) CSNPs with enhanced upconversion luminescence were successfully prepared by changing the doping pair of lanthanide ions in core. The synthesized RGB CSNPs were fabricated into environment friendly luminescent ink by sequential surface modification by PAA ligand and dispersing in mixture solvent of ethanol, water and glycerol. Comparative results showed that the fluorescence enhanced RGB CSNPs inks were more suitable for inkjet printing of multicolored, complex and high resolution luminescent anti-counterfeiting patterns on paper substrates.

18.
Hum Vaccin Immunother ; 16(1): 76-79, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31403888

RESUMO

From 2017 to 2018, Guangzhou experienced a shortage in 3-6 types of National Immunization Program (NIP) vaccines. To evaluate the current situation and causes of the NIP vaccine shortage, we analysed the duration, intensity and causes of the shortage from data in the vaccine information system of the Guangzhou Center for Disease Control and Prevention; we also proposed countermeasures to resolve the shortage. In 2017, there were shortages of three types of NIP vaccines in Guangzhou. The most affected vaccines were inactivated poliovirus (IPV) vaccine and meningococcal group AC (MenAC) vaccine, accounting for 39.5% and 16.5% of the reported shortages, respectively. In 2018, the shortage extended to six vaccine types; the most affected were diphtheria, tetanus and pertussis (DTP) vaccine, MenAC vaccine, and Bacille Calmette Guerin (BCG) vaccine. The four main causes for the shortage were: 1) an insufficient production capacity; 2) a delay in batch issuance; 3) vaccine-related events; and 4) an extended bidding procurement cycle. Four solutions are proposed: 1) expand production output; 2) exempt creditworthy enterprises from batch inspections; 3) establish alternative enterprises and emergency use authorizations; and 4) establish public health funds and stockpile storage systems.

19.
Langmuir ; 35(35): 11503-11511, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31365824

RESUMO

Development of advanced fluorescent materials for constructing a secure and unclonable encryption is urgently required; however, their application in anti-counterfeiting applications is a great challenge. In this work, we proposed and synthesized a new type of upconversion nanoparticles@carbon dots@meso-SiO2 nanohybrids by integrating two fluorescent materials of lanthanide-doped NaYF4 upconversion nanoparticles (UCNPs) and carbon dots (CDs) into mesoporous silica (mSiO2) to produce a novel sandwichlike core-shell structure and a dual-mode fluorescence from UCNPs and CDs. By tailoring the UCNP core of different upconversion luminescence, all three kinds of dual-mode luminescent UCNPs@CDs@mSiO2 nanohybrids exhibited typical RGB upconversion luminescence under a 980 nm laser and blue downconversion luminescence under a 365 nm UV light. Due to strong the hydrophilic nature of the nanohybrids, they can be further fabricated into environmentally benign luminescent inks for creating highly secured, fluorescent-based, three-dimensional anti-counterfeiting barcodes via inkjet printing. The resultant UCNPs@CDs@mSiO2 inks with a dual-mode and tunable luminescence nature endow the inkjet-printing barcodes with an extremely high encoding capacity and high security. Such dual-mode fluorescent inks and barcodes are simple to fabricate, easy to view, efficient for coding, and difficult to clone, thus making them promising nanomaterials for anti-counterfeiting applications.

20.
Dalton Trans ; 48(20): 6971-6983, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31044193

RESUMO

Development of advanced luminescent nanomaterials and technologies is of great significance for anti-counterfeiting applications in global economy, security, and human health, but has proved to be a great challenge. In this work, we design, synthesize, and characterize mono-disperse, dumbbell-shaped lanthanide-doped NaYF4@NaGdF4 core-shell nanoparticles (CSNPs) with dual-mode fluorescence by coating the NaGdF4:Ln'3+ shell onto NaYF4:Ln3+ core nanospheres via a two-step oleic acid mediated thermal decomposition process. Different from the conventional synthesis method to produce spherical nanoparticles, the epitaxial growth of the NaGdF4:Ln'3+ shell onto the nanosphere cores and the lattice mismatch between ß-NaGdF4 and ß-NaYF4 nanocrystals enable the formation of dumbbell-shaped CSNPs, as evidenced by the morphological evolution of CSNPs and as explained by the Ostwald ripening growth mechanism. By tailoring different doped lanthanide ions in the core and the shell, the resultant CSNPs exhibit tunable but different up-/down-conversion luminescence under the irradiation of a 980 nm laser and 254 nm UV light, respectively. Finally, these hydrophilic CSNPs are further fabricated into environmentally benign luminescent inks for inkjet printing to create a variety of dual-mode fluorescent patterns (peacock, temple, and a logo of "Hunan University of Technology") on different paper-based substrates (A4 paper, envelope, and postcard). Our dual-mode light-responsive CSNPs, along with an easy fabrication method, provide a simple and promising material and technique for anti-counterfeiting applications.

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