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1.
World J Clin Cases ; 9(26): 7772-7785, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34621827

RESUMO

BACKGROUND: Several techniques of nasogastric tube (NGT) insertion have been described in the literature with different success rates. AIM: To systematically search the literature and conduct a meta-analysis comparing the success rates, insertion time and complications associated with different techniques of NGT insertion in anesthetized and intubated patients. METHODS: An electronic search of the PubMed, Scopus, CENTRAL (Cochrane Central Register of Controlled Trials), and Google Scholar databases were performed up to October 31, 2019. We included 17 randomized controlled trials with 2500 participants in the meta-analysis. RESULTS: As compared to the conventional method, successful insertion of the NGT on first attempt was higher with modified techniques such as the reverse Sellick's maneuver [relative risk (RR) 1.94; 95% confidence interval (CI): 1.62-2.31], use of a frozen NGT (RR 1.55; 95%CI: 1.13-2.13), inserting the NGT with neck flexion and lateral neck pressure (RR 1.64; 95%CI: 1.10-2.45), endotracheal tube-assisted (RR 1.88; 95%CI: 1.52-2.32) and video-assisted placements (RR 1.60; 95%CI: 1.31-1.95). All the modified techniques also led to comparatively higher insertion success rates than the conventional technique. CONCLUSION: The use of modified techniques of NGT insertion such as the reverse Sellick's maneuver, neck flexion with lateral neck pressure, frozen NGT, endotracheal tube-guided or video-assisted methods result in a significantly better chance of successful tube insertion at first attempt as compared to the conventional technique. All modified techniques also significantly improve the overall chance of successful NGT placement as compared to the conventional method.

2.
Opt Express ; 29(19): 30579-30589, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34614780

RESUMO

This paper presents a new design of linear-polarization metasurface converter with arbitrary polarization rotating angle. The linear-polarization conversion is achieved by first separating the linearly polarized incident wave into two orthogonal circularly polarized waves, then adding an additional phase to one of the circularly polarized waves, and finally recombining these two circularly polarized waves into a linearly polarized wave and reflecting it towards free space. A practical unit cell operating at 10 GHz with sandwich structure is applied to realize the linear-polarization metasurface converter, which consists of a top-layer square patch, a middle-layer ground plane, a bottom-layer 90° quadrature hybrid coupler, and two vias connecting the top layer and bottom layer. The proposed linear-polarization metasurface converter is analyzed theoretically and demonstrated by both simulating and experimental results.

3.
Opt Express ; 29(16): 25709-25719, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34614894

RESUMO

Metasurfaces have shown extraordinary light-manipulation abilities, however, most of them deal with free-space waves. It is highly desirable to develop a guided wave-driven metasurface which can extract the in-plane guided modes in the waveguide and mold it into the desired out-of-plane free-space modes. In this paper, an all-dielectric guided wave-driven metasurface, composed of an array of silicon meta-atoms on top of a silicon nitride waveguide, is proposed and simulatively demonstrated. When directly driven by fundamental transverse electric (TE00) and fundamental transverse magnetic (TM00) guided modes at operation wavelength 1.55 µm, the guided wave-driven metasurface converts them into y-polarized and x-polarized free-space light, respectively, and focuses them at different focal points, with polarization extinction ratio over 27 dB, thus simultaneously realizing triple functions of coupling guided modes to free-space waves, bifocal metalens and polarization demultiplexing. Our work offers an alternate way to control light across photonic integrated devices and free-space platforms.

4.
Opt Express ; 29(20): 32031-32041, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615282

RESUMO

We present a time-coding reconfigurable intelligent surface (RIS) enabled spread-spectrum secure wireless communication system. The time-coding spread-spectrum RIS is realized by altering the RIS between the two states of a perfect electrical conductor (PEC) and perfect magnetic conductor (PMC), according to a pseudo-random time sequence, respectively. This spectrum spreading function of the time-coding RIS can be simply applied to the secure wireless communication systems, providing a low-cost, easy-implementation encrypting architecture with the two key features of interception prevention and interference suppression. These two features together with the overall spread-spectrum secure wireless communication system are demonstrated by both theoretical analysis and experimental results using a designed 8 × 8 time-coding RIS.

5.
Soft Matter ; 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34617549

RESUMO

Halloysite nanotubes (HNTs) are one-dimensional clay nanomaterials with a length of 200-1000 nm and a diameter of ∼50 nm. Understanding the self-assembly behavior of such unique nanoparticles is important to develop their applications in functional devices. In this study, the "coffee-ring" patterns of HNTs are investigated which are formed by evaporation of the sessile droplets of HNT aqueous dispersion on different substrates. The coffee-ring pattern with various dimensions was characterized using a polarizing microscope (POM), a scanning electron microscope (SEM), and a 3D optical profilometer. The diameter, height, and area of the coffee-ring patterns depend on the concentration of HNT dispersion, the droplet volume, and surface wettability. POM and SEM results suggested that the nanotubes were highly ordered in the edge and the middle of the coffee-ring. The coffee-ring effect of HNTs could be suppressed by increasing the evaporation temperature of substrates or adding polymer additives. In addition, multiple-ring patterns consistent with protein rings surrounding HNT rings were formed, which can be utilized to detect the presence of proteins in biological samples. This work illustrated the relationship between the formation of coffee-ring patterns and the experimental conditions, which provided an additional research chance and allowed application development for HNTs using the liquid droplet self-assembly.

6.
Cell Rep ; 37(2): 109813, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34644565

RESUMO

A heterozygous missense mutation of the islet ß cell-enriched MAFA transcription factor (p.Ser64Phe [S64F]) is found in patients with adult-onset ß cell dysfunction (diabetes or insulinomatosis), with men more prone to diabetes than women. This mutation engenders increased stability to the unstable MAFA protein. Here, we develop a S64F MafA mouse model to determine how ß cell function is affected and find sex-dependent phenotypes. Heterozygous mutant males (MafAS64F/+) display impaired glucose tolerance, while females are slightly hypoglycemic with improved blood glucose clearance. Only MafAS64F/+ males show transiently higher MafA protein levels preceding glucose intolerance and sex-dependent changes to genes involved in Ca2+ signaling, DNA damage, aging, and senescence. MAFAS64F production in male human ß cells also accelerate cellular senescence and increase senescence-associated secretory proteins compared to cells expressing MAFAWT. These results implicate a conserved mechanism of accelerated islet aging and senescence in promoting diabetes in MAFAS64F carriers in a sex-biased manner.

7.
Antioxidants (Basel) ; 10(10)2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34679774

RESUMO

Lignin-carbohydrate complexes (LCCs) from different lignocellulosic biomass have shown biological qualities as antioxidant and immunostimulant. By contrast, the application of LCCs as protectant against neurotoxicity caused by different compounds is scarce. In this work, two kinds of LCCs with carbohydrate-rich and lignin-rich fractions were obtained from wheat stalk and used to protect against BPA-neurotoxicity in zebrafish. The results showed that BPA at a concentration of 500 µg/L results in neurotoxicity, including significant behavioral inhibition, and prevents the expression of central nervous system proteins in transgenic zebrafish models (Tg (HuC-GFP)). When the zebrafish was treated by LCCs, the reactive oxygen species of zebrafish decreased significantly with the change of antioxidant enzymes and lipid peroxidation, which was due to the LCCs' ability to suppress the mRNA expression level of key genes related to nerves. This is essential in view of the neurotoxicity of BPA through oxidative stress. In addition, BPA exposure had negative effects on the exercise behavior, the catalase (CAT) and superoxide dismutase (SOD) activity, and the larval development and gene expression of zebrafish larvae, and LCC preparations could recover these negative effects by reducing oxidative stress. In zebrafish treated with BPA, carbohydrate-rich LCCs showed stronger antioxidant activity than lignin-rich LCCs, showing their potential as a neuroprotective agents.

8.
J Biol Chem ; 297(4): 101144, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34473992

RESUMO

Huntington's disease (HD), a neurodegenerative disease characterized by progressive dementia, psychiatric problems, and chorea, is known to be caused by CAG repeat expansions in the HD gene HTT. However, the mechanism of this pathology is not fully understood. The translesion DNA polymerase θ (Polθ) carries a large insertion sequence in its catalytic domain, which has been shown to allow DNA loop-outs in the primer strand. As a result of high levels of oxidative DNA damage in neural cells and Polθ's subsequent involvement in base excision repair of oxidative DNA damage, we hypothesized that Polθ contributes to CAG repeat expansion while repairing oxidative damage within HTT. Here, we performed Polθ-catalyzed in vitro DNA synthesis using various CAG•CTG repeat DNA substrates that are similar to base excision repair intermediates. We show that Polθ efficiently extends (CAG)n•(CTG)n hairpin primers, resulting in hairpin retention and repeat expansion. Polθ also triggers repeat expansions to pass the threshold for HD when the DNA template contains 35 repeats upward. Strikingly, Polθ depleted of the catalytic insertion fails to induce repeat expansions regardless of primers and templates used, indicating that the insertion sequence is responsible for Polθ's error-causing activity. In addition, the level of chromatin-bound Polθ in HD cells is significantly higher than in non-HD cells and exactly correlates with the degree of CAG repeat expansion, implying Polθ's involvement in triplet repeat instability. Therefore, we have identified Polθ as a potent factor that promotes CAG•CTG repeat expansions in HD and other neurodegenerative disorders.

9.
Nanoscale ; 13(38): 16189-16196, 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34545905

RESUMO

Colloidal photonic crystals (CPCs) with a highly ordered crystal structure have attracted great attention in displays, colorimetric sensors and solar energy utilization fields. However, the easily cracking microstructure, inferior assembly efficiency and low refractive index contrast result in poor structural colors. Herein, we develop core-shell poly(styrene-acrylic)@polypyrrole (P(St-AA)@PPy) colloidal nanoparticles by the in situ chemical coupling reaction via droplet microfluidic technology. By membrane separation-assisted assembly (MSAA) and electrostatic spraying strategies, the P(St-AA)@PPy colloidal nanoparticles are assembled into the CPC film, which presents high assembly efficiency and saturated angle-independent structural colors, due to the light-absorbing PPy shell and hydrogen-bond interaction between nanoparticles. Benefitting from these outstanding performances, the P(St-AA)@PPy film shows excellent photothermal properties, which can realize a solar vaporization rate of 1.5825 kg m-2 h-1, corresponding to a light-to-vapor efficiency of 94.20%, under 1.0 sun solar irradiance conditions. Our findings open a path for the design of functional CPCs and new-generation photothermal applications.

10.
Nanomaterials (Basel) ; 11(9)2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34578641

RESUMO

Three-dimensional (3D) micronano structures have attracted much attention in tissue engineering since they can better simulate the microenvironment in vivo. Two-photon polymerization (TPP) technique provides a powerful tool for printing arbitrary 3D structures with high precision. Here, the desired 3D biocompatible hydrogel microscaffolds (3D microscaffold) with structure design referring to fibroblasts L929 have been fabricated by TPP technology, particularly considering the relative size of cell seed (cell suspension), spread cell, strut and strut spacing of scaffold. Modulation of the cell behavior has been studied by adjusting the porosity from 69.7% to 89.3%. The cell culture experiment results reveal that the obvious modulation of F-actin can be achieved by using the 3D microscaffold. Moreover, cells on 3D microscaffolds exhibit more lamellipodia than those on 2D substrates, and thus resulting in a more complicated 3D shape of single cell and increased cell surface. 3D distribution can be also achieved by employing the designed 3D microscaffold, which would effectively improve the efficiency of information exchange and material transfer. The proposed protocol enables us to better understand the cell behavior in vivo, which would provide high prospects for the further application in tissue engineering.

11.
Environ Microbiol ; 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34581470

RESUMO

Heterotrophic nitrifiers are able to oxidize and remove ammonia from nitrogen-rich wastewaters but the genetic elements of heterotrophic ammonia oxidation are poorly understood. Here, we isolated and identified a novel heterotrophic nitrifier, Alcaligenes ammonioxydans sp. nov. strain HO-1, oxidizing ammonia to hydroxylamine and ending in the production of N2 gas. Genome analysis revealed that strain HO-1 encoded a complete denitrification pathway but lacks any genes coding for homologous to known ammonia monooxygenases or hydroxylamine oxidoreductases. Our results demonstrated strain HO-1 denitrified nitrite (not nitrate) to N2 and N2 O at anaerobic and aerobic conditions respectively. Further experiments demonstrated that inhibition of aerobic denitrification did not stop ammonia oxidation and N2 production. A gene cluster (dnfT1RT2ABCD) was cloned from strain HO-1 and enabled E. coli accumulated hydroxylamine. Sub-cloning showed that genetic cluster dnfAB or dnfABC already enabled E. coli cells to produce hydroxylamine and further to 15 N2 from (15 NH4 )2 SO4 . Transcriptome analysis revealed these three genes dnfA, dnfB and dnfC were significantly upregulated in response to ammonia stimulation. Taken together, we concluded that strain HO-1 has a novel dnf genetic cluster for ammonia oxidation and this dnf genetic cluster encoded a previously unknown pathway of direct ammonia oxidation (Dirammox) to N2 .

12.
Technol Cancer Res Treat ; 20: 15330338211041193, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34520298

RESUMO

microRNA-342-3p plays an important role in tumor occurrence and development. However, the expression pattern and roles of microRNA-342-3p in nonsmall cell lung cancer remain poorly understood. In the current study, we explored the roles and underlying mechanisms of microRNA-342-3p in nonsmall cell lung cancer via gain- and loss-of-function analyses. We used quantitative reverse-transcription-polymerase chain reaction and western blotting assays to measure the expression levels of microRNA-342-3p in nonsmall-cell lung cancer and B-cell lymphoma-2. Furthermore, we used small interfering RNA and RNA mimics to analyze the functions and underlying mechanisms of microRNA-342-3p in nonsmall cell lung cancer cells. A luciferase reporter assay was performed to evaluate the direct binding site of the 5'-untranslated region of B-cell lymphoma-2 targeted by microRNA-342-3p. We found that the expression of microRNA-342-3p was significantly lower in nonsmall cell lung cancer cells and tissues than in normal cells and tissues. The upregulation of microRNA-342-3p suppressed cell proliferation while promoting apoptosis in H1975, H460, and H226 cells. The overexpression of microRNA-342-3p in nonsmall cell lung cancer cells led to the downregulation of mRNA and protein levels in B-cell lymphoma-2 cells. Thus, B-cell lymphoma-2 was identified as a direct target of microRNA-342-3p. These findings indicate that microRNA-342-3p inhibits the growth of nonsmall cell lung cancer by repressing the expression of B-cell lymphoma-2, which suggests that microRNA-342-3p could be a potential target for the treatment of nonsmall cell lung cancer.

13.
Arch Virol ; 2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34536128

RESUMO

Enterovirus 71 (EV71) poses a major threat to public health globally due to severe and even fatal hand, foot, and mouth disease (HFMD). However, no effective antiviral agents are available to treat HFMD caused by this virus. Polysaccharides have been shown to exhibit antiviral activity, and polysaccharides extracted from Picochlorum sp. 122 (PPE) could potentially be used to treat HFMD, but reports on their antiviral activity are limited. In this study, the antiviral activity of PPE against EV71 was verified in Vero cells. PPE was shown to limit EV71 infection, as demonstrated using an MTT assay and by observing the cellular cytopathic effect. In addition, a decrease in VP1 RNA and protein levels indicated that PPE effectively inhibits proliferation of EV71 in Vero cells. An annexin V affinity assay also indicated that PPE protects host cells from apoptosis through the AKT and ATM/ATR signalling pathways. These results demonstrate that PPE has potential as an antiviral drug to treat HFMD caused by EV71.

14.
Plant Biotechnol J ; 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34582620

RESUMO

Necrotrophic fungus Rhizoctonia solani Kühn (R. solani) causes serious diseases in many crops worldwide, including rice and maize sheath blight (ShB). Crop resistance to the fungus is a quantitative trait and resistance mechanism remains largely unknown, severely hindering the progress on developing resistant varieties. In this study, we found that resistant variety YSBR1 has apparently stronger ability to suppress the expansion of R. solani than susceptible Lemont in both field and growth chamber conditions. Comparison of transcriptomic profiles shows that the photosynthetic system including chlorophyll biosynthesis is highly suppressed by R. solani in Lemont but weakly in YSBR1. YSBR1 shows higher chlorophyll content than that of Lemont, and inducing chlorophyll degradation by dark treatment significantly reduces its resistance. Furthermore, three rice mutants and one maize mutant that carry impaired chlorophyll biosynthesis all display enhanced susceptibility to R. solani. Overexpression of OsNYC3, a chlorophyll degradation gene apparently induced expression by R. solani infection, significantly enhanced ShB susceptibility in a high-yield ShB-susceptible variety '9522'. However, silencing its transcription apparently improves ShB resistance without compromising agronomic traits or yield in field tests. Interestingly, altering chlorophyll content does not affect rice resistance to blight and blast diseases, caused by biotrophic and hemi-biotrophic pathogens, respectively. Our study reveals that chlorophyll plays an important role in ShB resistance and suppressing chlorophyll degradation induced by R. solani infection apparently improves rice ShB resistance. This discovery provides a novel target for developing resistant crop to necrotrophic fungus R. solani.

15.
ACS Chem Neurosci ; 12(18): 3410-3417, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34469110

RESUMO

Adenosine receptor (AR) radiotracers for positron emission tomography (PET) have provided knowledge on the in vivo biodistribution of ARs in the central nervous system (CNS), which is of therapeutic interest for various neuropsychiatric disorders. Additionally, radioligands that can image changes in endogenous adenosine levels in different physiological and pathological conditions are still lacking. The binding of known antagonist adenosine A1 receptor (A1R) radiotracer, [11C]MDPX, failed to be inhibited by elevated endogenous adenosine in a rodent PET study. Since most of the known AR PET radiotracers were antagonists, we propose that an A1R agonist radioligand may possess higher sensitivity to measure changes in endogenous adenosine concentration. Herein, we report our latest findings toward the development of a full agonist adenosine A1 radioligand for PET. Based on a 3,5-dicyanopyridine template, 16 new derivatives were designed and synthesized to optimize both binding affinity and functional activity, resulting in two full agonists (compounds 27 and 29) with single-digit nanomolar affinities and good subtype selectivity (A1/A2A selectivity of ∼1000-fold for compound 27 and 29-fold for compound 29). Rapid O-[11C]methylation provided [11C]27 and [11C]29 in high radiochemical yields and radiochemical purity. However, subsequent brain PET imaging in rodents showed poor brain permeability for both radioligands. An in vivo PET study using knockout mice for MDR 1a/a, BCRP, and MRP1 indicated that these compounds might be substrates for brain efflux pumps. In addition, in silico evaluation using multiparameter optimization identified high molecular weight and high polar surface area as the main molecular descriptors responsible for low brain penetration. These results will provide further insight toward development of full agonist adenosine A1 radioligands and also highly potent CNS A1AR drugs.


Assuntos
Proteínas de Neoplasias , Agonistas do Receptor Purinérgico P1 , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Adenosina , Animais , Camundongos , Tomografia por Emissão de Pósitrons , Distribuição Tecidual
16.
Appl Microbiol Biotechnol ; 105(19): 7395-7410, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34536105

RESUMO

In eukaryotes, myosin provides the necessary impetus for a series of physiological processes, including organelle movement, cytoplasmic flow, cell division, and mitosis. Previously, three members of myosin were identified in Magnaporthe oryzae, with class II and class V myosins playing important roles in intracellular transport, fungal growth, and pathogenicity. However, limited is known about the biological function of the class I myosin protein in the rice blast fungus. Here, we found that Momyo1 is highly expressed during conidiation and infection. Functional characterization of this gene via RNA interference (RNAi) revealed that Momyo1 is required for vegetative growth, conidiation, melanin pigmentation, and pathogenicity of M. oryzae. The Momyo1 knockdown mutant is defective in formation of appressorium-like structures (ALS) at the hyphal tips. In addition, Momyo1 also displays defects on cell wall integrity, hyphal hydrophobicity, extracellular enzyme activities, endocytosis, and formation of the Spitzenkörper. Furthermore, Momyo1 was identified to physically interact with the MoShe4, a She4p/Dim1p orthologue potentially involved in endocytosis, polarization of the actin cytoskeleton. Overall, our findings provide a novel insight into the regulatory mechanism of Momyo1 that is involved in fungal growth, cell wall integrity, endocytosis, and virulence of M. oryzae. KEY POINTS: • Momyo1 is required for vegetative growth and pigmentation of M. oryzae. • Momyo1 is essential for cell wall integrity and endocytosis of M. oryzae. • Momyo1 is involved in hyphal surface hydrophobicity of M. oryzae.


Assuntos
Ascomicetos/patogenicidade , Endocitose , Miosinas , Ascomicetos/crescimento & desenvolvimento , Miosinas/genética , Virulência
17.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 38(9): 833-837, 2021 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-34487524

RESUMO

OBJECTIVE: To analyze gene variants in a Chinese pedigree with oculocutaneous albinism (OCA). METHODS: Gene sequencing of the proband and his parents was performed using chip capture high-throughput sequencing and Sanger sequencing techniques, and PolyPhen-2, SIFT, MutationTaster, and FATHMM software were used to predict the function of new variants. At the same time,the pedigree and variant genes of 4 albinism patients from this pedigree were analyzed. RESULTS: Sequencing results showed that the proband's TYR gene (NM_000372) has c.230G>A (p.Arg77Gln) and c.120_121insG (p.Asp42GlyfsTer35) compound heterozygous variants. The proband's father carries c.230G>A heterozygous variant, and the mother carries c.120_121insG heterozygous variant, indicating that the proband's two variants are from his father and mother. The former is a known missense variant, which can cause abnormal or loss of the original function of the protein polypeptide chain. The latter c.120_121insG(p.Asp42GlyfsTer35) is an unreported frameshift variant of the TYR gene subregion (EX1; CDS1). PolyPhen-2, SIFT, MutationTaster and FATHMM predictions are all prompted as "harmful variants". This variant caused the amino acid encoded protein to terminate prematurely, producing a truncated protein, which eventually formed a 76-amino acid short-type TYR protein instead of the 529-amino acid wild-type TYR protein. Through the pedigree analysis, the four patients in the pedigree are all of the same type of compound heterozygous variants, and the disease-causing genes are all from the patient's parents. They belong to a special form of consanguineous marriage within 5 generations. CONCLUSION: The compound heterozygous variants of c.230G>A (p.Arg77Gln) and c.120_121insG (p.Asp42GlyfsTer35) of the TYR gene may underlie the disease in this pedigree. The gene sequencing results enrich the variant spectrum of the TYR gene, and has facilitated molecular diagnosis for the patient.


Assuntos
Albinismo Oculocutâneo , Albinismo Oculocutâneo/genética , Consanguinidade , Heterozigoto , Humanos , Mutação , Linhagem
18.
Sci Total Environ ; 805: 150210, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34534871

RESUMO

As more and more countries have prohibited the manufacture and sale of plastic products with bisphenol A (BPA), a number of bisphenol analogues (BPs), including BPS, BPF and BPAF, have gradually been used as its primary substitutes. Ideally, substitutes used to replace chemicals with environmental risks should be inert, so it makes sense that the risk of the similar chemical substitutes (BPS, BPF, and BPAF) should be assessed before they used. Therefore, in the present study, the neurotoxicity of four BPs at environmentally relevant concentration (200 µg/L) were systematically compared using zebrafish as a model. Our results showed that the four BPs (BPA, BPS, BPF and BPAF) exhibited no obvious effect on the hatchability, survival rate and body length of zebrafish larvae, noteworthily a significant inhibitory effect on spontaneous movement at 24 hpf was observed in the BPA, BPF and BPAF treatment groups. Behavioral tests showed that BPAF, BPF and BPA exposure significantly reduced the locomotor activity of the larvae. Additionally, BPAF treatment adversely affected motor neuron axon length in transgenic lines hb9-GFP zebrafish and decreased central nervous system (CNS) neurogenesis in transgenic lines HuC-GFP zebrafish. Intriguingly, BPAF displayed the strongest effects on the levels and metabolism of neurotransmitters, followed by BPF and BPA, while BPS showed the weakest effects on neurotransmitters. In conclusion, our study deciphered that environmentally relevant concentrations of BPs exposure exhibited differential degrees of neurotoxicity, which ranked as below: BPAF > BPF ≈ BPA > BPS. The possible mechanisms can be partially ascribed to the dramatical changes of multiple neurotransmitters and the inhibitory effects on neuronal development. These results suggest that BPAF and BPF should be carefully considered as alternatives to BPA.

19.
J Mater Chem B ; 9(33): 6691-6702, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34382634

RESUMO

Hydroxyapatite (HA) is the most commonly used orthopedic implant material. In recent years, the emergence of cationic doped hydroxyapatite has revealed more possibilities for the biological application of HA. Conventional HA does not promote new bone formation because of its poor osteoinductive activity, and has a similar density to that of bone, leading to difficulty in distinguishing both via imaging. Magnesium ions are useful for regulating the cellular behavior and promoting bone regeneration. Ba ion related compounds, such as BaSO4, have a strong X-ray shielding effect. In this study, Ba/Mg@HA was synthesized to prepare Ba/Mg@HA/PLGA composites, and we aimed to investigate if Ba/Mg@HA/PLGA composites enhanced bone repair on osteoblasts and tibial defects, as well as the X-ray and CT imaging ability of bone implants in rats. The in vitro experimental results showed that the Ba/Mg@HA/PLGA composites significantly improved the attachment and osteogenic differentiation of MC3T3-E1 cells. These include the promotion of mineral deposition, enhancement of alkaline phosphatase activity, upregulation of OCN and COL-1 gene expression, and increase in COL-1 and OCN protein expression in a time- and concentration-dependent manner. The in vivo experimental results showed that the Ba/Mg@HA/PLGA composites significantly increased the rate of bone defect healing and the expression of BMP-2 and COL-1 in the bones of rats. X-ray and CT imaging results showed that the Ba/Mg@HA/PLGA composites enhanced the X-ray imaging ability. These findings indicate that the Ba/Mg@HA/PLGA composites can effectively promote bone formation and improve the X-ray and CT imaging abilities to a certain extent.

20.
Front Immunol ; 12: 736129, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34447391

RESUMO

The present study evaluated the protection of Lactiplantibacillus plantarum CCFM8661, a candidate probiotic with excellent benzopyrene (B[a]P)-binding capacity in vitro, against B[a]P-induced toxicity in the colon and brain of mice. Mice that received B[a]P alone served as the model group. Each mouse in the L. plantarum treatment groups were administered 2×109 colony forming unit (CFU) of L. plantarum strains once daily, followed by an oral dose of B[a]P at 50 mg/kg body weight. Behavior, biochemical indicators in the colon and brain tissue, and the gut microbiota composition and short-chain fatty acid (SCFA) levels in the gut were investigated. Compared to the treatment in the model group, CCFM8661 treatment effectively reduced oxidative stress in the brain, improved behavioral performance, increased intestinal barrier integrity, and alleviated histopathological changes in mice. Moreover, CCFM8661 increased the gut microbiota diversity and abundance of Ruminococcus and Lachnospiraceae and reduced the abundance of pro-inflammatory Turicibacter spp. Additionally, the production of SCFAs was significantly increased by L. plantarum CCFM8661. Our results suggest that CCFM8661 is effective against acute B[a]P-induced toxicity in mice and that it can be considered as an effective and easy dietary intervention against B[a]P toxicity.

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