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1.
Angew Chem Int Ed Engl ; 63(20): e202403474, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38506404

RESUMO

Per- and polyfluoroalkyl substances (PFAS) pose a rapidly increasing global problem as their widespread use and high stability lead worldwide to water contamination, with significant detrimental health effects.[1] Supramolecular chemistry has been invoked to develop materials geared towards the specific capture of PFAS from water,[2] to reduce the concentration below advisory safety limits (e.g., 70 ng/L for the sum of perfluorooctane sulfonic acid, PFOS and perfluorooctanoic acid, PFOA). Scale-up and use in natural waters with high PFAS concentrations has hitherto posed a problem. Here we report a new type of host-guest interaction between deca-ammonium-functionalized pillar[5]arenes (DAF-P5s) and perfluoroalkyl acids. DAF-P5 complexes show an unprecedented 1 : 10 stoichiometry, as confirmed by isothermal calorimetry and X-ray crystallographic studies, and high binding constants (up to 106 M-1) to various polyfluoroalkyl acids. In addition, non-fluorinated acids do not hamper this process significantly. Immobilization of DAF-P5s allows a simple single-time filtration of PFAS-contaminated water to reduce the PFOS/PFOA concentration 106 times to 15-50 ng/L level. The effective and fast (<5 min) orthogonal binding to organic molecules without involvement of fluorinated supramolecular hosts, high breakthrough capacity (90 mg/g), and robust performance (>10 regeneration cycles without decrease in performance) set a new benchmark in PFAS-absorbing materials.

2.
J Org Chem ; 88(22): 15658-15665, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37903243

RESUMO

Here we report the first asymmetric synthesis of large chiral macrocycles with chiral sulfur atoms. Building on stereospecific SuFEx and SuPhenEx click chemistries, this approach utilizes disulfonimidoyl fluorides and disulfonimidoyl p-nitrophenolates─which are efficient building blocks with two chiral sulfur centers, and diphenols to efficiently form novel S-O bonds. Characteristic results include the enantiospecific one-step synthesis of rings consisting of 21-58 members and characterization of both enantiomers (R,R and S,S) by e.g. X-ray crystallography.

3.
Molecules ; 28(20)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37894487

RESUMO

We developed an improved, robust synthesis of a series of pillar[6]arenes with a varying number (0-3) of quinone moieties in the ring. This easy-to-control variation yielded a gradually less electron-rich cavity in going from zero to three quinone units, as shown from the strength of host-guest interactions with silver ions. Such macrocycle-Ag2 complexes themselves were shown to display an unprecedented, sharp distinction between terminal alkynes, which strongly bound to such complexes, and internal alkynes, internal alkenes and terminal alkenes, which do hardly bind.

4.
Molecules ; 27(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35164137

RESUMO

Foaming effect strongly impacts the physical and mechanical properties of foam glass materials, but an understanding of its mechanism especially at the molecular level is still limited. In this study, the foaming effects of dextrin, a mixture of dextrin and carbon, and different carbon allotropes are investigated with respect to surface morphology as well as physical and mechanical properties, in which 1 wt.% carbon black is identified as an optimal choice for a well-balanced material property. More importantly, the different foaming effects are elucidated by all-atomistic molecular dynamics simulations with molecular-level insights into the structure-property relationships. The results show that smaller pores and more uniform pore structure benefit the mechanical properties of the foam glass samples. The foam glass samples show excellent chemical and thermal stability with 1 wt.% carbon as the foaming agent. Furthermore, the foaming effects of CaSO4 and Na2HPO4 are investigated, which both create more uniform pore structures. This work may inspire more systematic approaches to control foaming effect for customized engineering needs by establishing molecular-level structure-property-process relationships, thereby, leading to efficient production of foam glass materials with desired foaming effects.

5.
Virus Genes ; 57(2): 194-204, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33559837

RESUMO

The structural protein VP3 of infectious bursal disease virus (IBDV) plays a critical role in viral assembly, replication, immune escape, and anti-apoptosis. Interaction between VP3 and host protein factors can affect stages in the viral replication cycle. In this study, 137 host proteins interacting with VP3 protein were screened through liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomics approach. The functions and relevance of the proteins were obtained through bioinformatics analysis. Most VP3-interacting proteins were linked to binding, catalytic activity, and structural molecular activity, and performed functions in cell parts and cells. Biological functions of VP3-interacting proteins were mainly relevant to "Cytoskeleton", "Translation", and "Signal transduction mechanisms", involving ribosomes, "Tight junction", regulation of actin cytoskeleton, and other pathways. Six potential VP3-interacting proteins in host cells were knocked down, and vimentin, myosin-9, and annexin A2 were found to be related to IBDV replication. This study would help explore regulatory pathways and cellular mechanisms in IBDV-infected cells, and also provided clues for the in-depth study of VP3 biological functions and IBDV replication or pathogenesis.


Assuntos
Vírus da Doença Infecciosa da Bursa/metabolismo , Proteínas Estruturais Virais/metabolismo , Animais , Linhagem Celular , Embrião de Galinha , Cromatografia Líquida , Fibroblastos/virologia , Ligação Proteica , Mapas de Interação de Proteínas , Proteínas/metabolismo , Proteoma/metabolismo , Espectrometria de Massas em Tandem , Replicação Viral
6.
Int J Health Plann Manage ; 34(4): e1661-e1674, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31385373

RESUMO

China's population is aging rapidly, while the traditional long-term care (LTC) system that heavily relies on families is eroding. In response, China has embarked on a journey of policy experimentation for long-term care insurance (LTCI) since 2016, launching LTCI pilots in 15 pioneer cities. These pilots have a great diversity in participation, eligibility, and provision. This paper estimates the prevalence of LTC needs and analyzes the impact of the LTCI pilots on access. Although substantial progress has been achieved, the overall coverage of LTCI is still relatively small, and a large proportion of vulnerable people needing LTC seem to be left behind because of the strict eligibility criteria. This analysis suggests that future policy experimentation on LTCI reform in China needs to address the following pressing policy issues: expanding the coverage of LTCI; narrowing rural-urban disparities in access; improving access for vulnerable subpopulations; and reducing the heavy reliance on institutional care.


Assuntos
Política de Saúde , Acessibilidade aos Serviços de Saúde , Seguro de Assistência de Longo Prazo , Fatores Etários , Idoso , China , Pessoas com Deficiência/estatística & dados numéricos , Acessibilidade aos Serviços de Saúde/organização & administração , Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Humanos , Cobertura do Seguro/estatística & dados numéricos , Seguro de Assistência de Longo Prazo/estatística & dados numéricos , Pessoa de Meia-Idade
7.
Wei Sheng Yan Jiu ; 48(4): 633-637, 2019 Jul.
Artigo em Zh | MEDLINE | ID: mdl-31601348

RESUMO

OBJECTIVE: To test the performance of direct chemiluminescence immunoassay(CLIA) in the determination of serum 25-hydroxyvitamin D [25(OH)D] concentration. METHODS: The CLIA analyzer of Italy DiaSorin was used to measure the 25(OH)D concentrations in the Standard Reference Material 972 a of National Institute of Standards and Technology, DiaSorin control materials, blind samples of Vitamin D External Quality Assessment Scheme(DEAQS), and outpatient serum samples. The functional sensitivity, precision, accuracy, recovery, and linearity were evaluated, and the samples of mild hemolysis, 5 days' storage at 4 ₿ and >1 year's storage at-80 ₿were tested for 25(OH)D. RESULTS: The functional sensitivity was<4 ng/mL. The coefficient of variations of intra-and inter batch were<8. 1%. The relative deviation was-3. 1%-5. 7%. The recovery rates were 82. 8%-112. 9% and it had good linearity in the range of 7. 6-128. 1 ng/mL. Compared with fresh serum, the serum 25(OH)D concentration was not affected by mild hemolysis or being stored at 4 ₿for 5 days, but averagely decreased at 7. 6% by being stored at-80 ₿for more than 1 year. Compared with others, the deviation was-2. 9%-3. 6%. The differences in precision, accuracy and recovery of this method among the three different hospitals is slightly. CONCLUSION: The performance of direct CLIA for 25(OH)D assay meet the basic technical requirements for laboratory medicine, and is laborsaving and timesaving.


Assuntos
Luminescência , Vitamina D/análogos & derivados , 25-Hidroxivitamina D 2 , Calcifediol , Imunoensaio , Vitamina D/sangue
8.
Soft Matter ; 12(40): 8348-8358, 2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-27714375

RESUMO

To elucidate the mechanism underlying the effect of polymer/solid interfacial interactions on the dynamics of thin polymer films, the glass transition of thin end-functionalized polystyrene films supported on SiO2-Si, such as proton-terminated PS (PS-H), α,ω-dicarboxy-terminated PS (PS-COOH), and α,ω-dihydroxyl-terminated PS (PS-OH), was investigated. All the PS films exhibited a substantial depression in Tg with decreasing film thickness, while the extent of such depression was strongly dependent on the chemical structure of the end groups and molecular weights. It was found that T - T of the various PS films increased linearly with increasing hads/Rg, in which hads is the thickness of the interfacial adsorbed layer and Rg is the radius of gyration of PS. The hads/Rg is a direct reflection of the macromolecular chain conformation within the adsorbed layer which was affected by its end groups and molecular weights. These findings are in line with the work of Napolitano, and present direct experimental evidence.

9.
Zhonghua Yu Fang Yi Xue Za Zhi ; 50(3): 244-9, 2016 Mar.
Artigo em Zh | MEDLINE | ID: mdl-26957243

RESUMO

OBJECTIVE: To investigate the effect of short and long term exposure to SiO2 nanoparticles on microRNA expression level in human bronchial epithelial cells(16HBE cells). METHODS: The 16HBE cells were exposed to 5, 10, 15, 20, 25, 30 and 40 µg/ml SiO2 nanoparticles for 24 h to detect the cell viability by using CCK-8 assay. The inhibition rate of proliferation activity and half inhibitory concentration (IC50) were calculated. The 16HBE cells were exposed to 10 µg/ml SiO2 nanoparticles for 10 and 30 generations, named P10 and P30, and the control P0 was set. The cells were treated with SiO2 nanoparticles at 0, 1/4 IC50, 1/2 IC50 and IC50 concentration and µm-SiO2 at IC50 concentration for 24 h, and the control serum-free culture medium was set. Agilent miRNAs microarray chip was used to screen differentially expressed miRNAs in P10, P30 and P0 groups. The expression level of miRNA was detected by reverse transcription fluorescence quantitative polymerase chain reaction (qRT-PCR). RESULTS: The inhibition rate of proliferation activity of 5, 10, 15, 20, 25,30,40 µg/ml group were (-3.33 ± 3.80)%, (20.40 ± 11.73)%, (39.08 ± 5.53)%, (55.10 ± 5.78)%, (66.42 ± 9.60)%, (71.67 ± 7.34)%, (81.43 ± 5.37)%, respectively; F=129.11, P<0.001. The IC50 (95%CI) was 18.35 (15.82-20.72) µg/ml. The expression level of miRNA-494-3p in P0, P10 and P30 were 1.00, 0.45 ± 0.08, 0.28 ± 0.07, respectively; F=60.77, P<0.001. miRNA-19a-3p were 1.00, 2.27 ± 0.45, 1.06 ± 0.19, respectively; F=30.05, P<0.001. miRNA-148b-3p were 1.00, 1.78 ± 0.29, 0.88 ± 0.19, respectively; F=30.23, P<0.001. Compared to control group, the expression level of miRNA-494-3p in 5, 10, 20 µg/ml SiO2 nanoparticles groups and 20 µg/ml µm-SiO2 group were 0.99 ± 0.04, 1.38 ± 0.19, 2.13 ± 0.14, 0.81 ± 0.25, respectively; F=57.03, P<0.001. miRNA-19a-3p were 0.91 ± 0.03, 1.12 ± 0.03, 0.53 ± 0.01, 0.86 ± 0.01, respectively; F=408.78, P<0.001. miRNA-148b-3p were 0.95 ± 0.02, 1.22 ± 0.00, 0.54 ± 0.02, 1.15 ± 0.04 respectively; F=264.14, P<0.001. CONCLUSION: Short and long term exposure to SiO2 nanoparticles can affect the expression level of miRNAs in 16HBE cells. The expressions of miRNA-494-3p after long and short period exposure are different.


Assuntos
Células Epiteliais/efeitos dos fármacos , MicroRNAs/metabolismo , Nanopartículas/química , Dióxido de Silício/química , Células Cultivadas , Células Epiteliais/metabolismo , Humanos , Análise de Sequência com Séries de Oligonucleotídeos
10.
Public Health Nutr ; 18(12): 2211-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25517289

RESUMO

OBJECTIVE: To examine the vitamin D status, SNP of the vitamin D receptor gene (VDR) and the effects of vitamin D supplementation on parathyroid hormone and insulin secretion in adult males with obesity or normal weight in a subtropical Chinese city. DESIGN: An intervention trial. SETTING: Shenzhen City, Guangdong Province, China. SUBJECTS: From a cross-sectional survey conducted from June to July, eighty-two normal-weight and ninety-nine obese males (18-69 years) were screened to analyse their vitamin D status and for five SNP of VDR. From these individuals, in the same season of a different year, obese and normal-weight male volunteers (twenty-one per group) were included for an intervention trial with oral vitamin D supplementation at 1250 µg/week for 8 weeks. RESULTS: For the survey, there was no significant difference (P>0·05) in baseline circulating 25-hydroxyvitamin D concentrations or in the percentages of participants in different categories of vitamin D status between the two groups. The VDR SNP, rs3782905, was significantly associated with obesity (P=0·043), but none of the examined SNP were correlated with serum 25-hydroxyvitamin D when adjusted for age, BMI and study group. After vitamin D supplementation, serum 25-hydroxyvitamin D concentration, hypersecretions of parathyroid hormone and insulin, and insulin resistance in the obese were changed beneficially (P<0·05); however, the increase in serum 25-hydroxyvitamin D was less than that of the normal-weight men. CONCLUSIONS: For obese and normal-weight men of subtropical China, the summer baseline vitamin D status was similar. However, oral vitamin D supplementation revealed a decreased bioavailability of vitamin D in obese men and ameliorated their hypersecretion of parathyroid hormone and insulin resistance.


Assuntos
Suplementos Nutricionais , Resistência à Insulina , Obesidade/sangue , Hormônio Paratireóideo/metabolismo , Vitamina D/sangue , Adolescente , Adulto , Idoso , Povo Asiático , Disponibilidade Biológica , Índice de Massa Corporal , China , Estudos Transversais , Relação Dose-Resposta a Droga , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Polimorfismo de Nucleotídeo Único , Receptores de Calcitriol/sangue , Receptores de Calcitriol/genética , Vitamina D/administração & dosagem , Vitamina D/farmacocinética , Adulto Jovem
11.
Technol Health Care ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39331119

RESUMO

BACKGROUND: Lung cancer is one of the most common cancers worldwide, with the incidence increasing each year. It is crucial to improve the prognosis of patients who have lung cancer. Non-Small Cell Lung Cancer (NSCLC) accounts for the majority of lung cancer. Though its prognostic significance in NSCLC has not been often documented, Endoplasmic Reticulum (ER) stress has been identified to be implicated in tumour malignant behaviours and resistance to treatment. OBJECTIVE: This work aimed to develop a gene profile linked to ER stress that could be applied to predictive and risk assessment for non-small cell lung cancer. METHODS: Data from 1014 NSCLC patients were sourced from The Cancer Genome Atlas (TCGA) database, integrating clinical and Ribonucleic Acid (RNA) information. Diverse analytical techniques were utilized to identify ERS-associated genes associated with patients' prognoses. These techniques included Kaplan-Meier analysis, univariate Cox regression, Least Absolute Shrinkage and Selection Operator regression analysis (LASSO) regression, and Pearson correlation analysis. Using a risk score model obtained from multivariate Cox analysis, a nomogram was created and validated to classify patients into high- and low-risk groups. The study employed the CIBERSORT algorithm and Single-Sample Gene Set Eenrichment Analysis (ssGSEA) to investigate the tumour immune microenvironment. We used the Genomics of Drug Sensitivity in Cancer (GDSC) database and R tools to identify medicines that could be responsive. RESULTS: Four genes - FABP5, C5AR1, CTSL, and LTA4H - were chosen to create the risk model. Overall Survival (OS) was considerably lower (P< 0.05) in the high-risk group. When it came to predictive accuracy, the risk model outperformed clinical considerations. Several medication types that are sensitive to high-risk groups were chosen. CONCLUSION: Our study has produced a gene signature associated with ER stress that may be employed to forecast the prognosis and therapeutic response of non-small cell lung cancer patients.

12.
Materials (Basel) ; 17(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38673085

RESUMO

This study utilized bismaleimide (BMI) resin, reinforced with introduced ether bonds, as a binding matrix, in combination with silicon carbide (SiC), for the fabrication of composite materials. A thorough investigation was conducted to assess the influence of diverse processing parameters on the mechanical properties and high-temperature thermo-oxidative stability of these composites. Experimental results indicate a notable improvement in the mechanical properties of the composites upon the incorporation of ether bonds, in contrast to their unmodified counterparts. The variation in performance among composites with different ratios and molding densities is apparent. Within a certain range, an increase in resin content and molding density is correlated with improved bending strength in the composites. With a resin content of 27.5 vol% and a molding density of 2.31 g/cm3, the composite achieved a maximum flexural strength of 109.52 MPa, representing a 24% increase compared to its pre-modification state. Even after exposure to high-temperature heat treatment, the composites displayed commendable mechanical properties compared to their pre-ether bond modification counterparts, maintaining 74.5% of the strength of the untreated composites at 300 °C. The scanning electron microscopy (SEM) microstructures of composite materials correlate remarkably well with their mechanical properties.

13.
Materials (Basel) ; 17(8)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38673155

RESUMO

Currently, the sol-gel technique is employed in the synthesis of high-performance vitrified bonds; however, its application in the fabrication of stacked abrasives has been minimally explored. Furthermore, the methods utilized in the production of abrasive particles for stacked abrasives are technically challenging and incur high costs, which hinders their actual industrial application. Consequently, this study utilizes the sol-gel approach to synthesize a Na2O-B2O3-SiO2 ternary system vitrified bond powder and employs a molding and crushing method, which offers a lower technological barrier and reduced preparation costs, for the production of abrasive particles subsequently fabricating corundum stacked abrasives. Upon setting the binder composition to a molar ratio of n(SiO2):n(B2O3):n(Na2O) = 65:23:12, it was observed that the crystallization within the glass matrix was minimized and the optimal sintering temperature for the synthesized laminate abrasive to be sustained at 820 °C. At the aforementioned temperature, the binder melt is capable of flowing uniformly amongst the abrasive granules, thereby ensuring a robust encapsulation of the particles. The average single particle compressive strength of the prepared corundum stacked abrasive with a grain size of forty mesh can reach the highest of all composition points at 28.56 N and the average single particle compressive strength of the prepared diamond stacked abrasive is 28.14 N.

14.
J Colloid Interface Sci ; 673: 301-311, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38878365

RESUMO

The development of catalysts with suitable adsorption behavior for the reaction molecules and the elucidation of their internal structure-adsorption-catalytic activity relationships are crucial for the electrooxidation of 5-hydroxymethylfurfural (HMF). In this work, NiO-CuO heterostructures with a spontaneous built-in electric field (BEF) are specifically designed and used to regulate the OH- adsorption site for freeing up the active site of HMF for the HMF oxidation reaction (HMFOR). The mechanism driving electron pumping/accumulation of the BEF is examined by X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). Electrochemical data and theoretical calculations show that BEF modulates the adsorption energy and adsorption site of substrate molecules, thereby enhancing the performance of HMFOR and hydrogen evolution reaction (HER). Notably, the NiO-CuO electrode demonstrates high 2,5-Furandicarboxylic acid (FDCA) selectivity (99.76 %) and generation rate (13.79 mmol gcat-1 h-1). It only requires 1.33 V to obtain a current density of 10 mA cm-2 for HMFOR-coupled H2 evolution. This research introduces a novel approach by regulating the adsorption of reactive molecules for HMFOR-assisted H2 evolution.

15.
Cureus ; 16(5): e61030, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38915970

RESUMO

Background Chemoprevention, such as berberine, has been developed as an alternative or complementary strategy to colonoscopy surveillance and has shown promise in reducing the morbidity and mortality of colorectal cancer. This study aims to evaluate the cost-effectiveness of berberine for postpolypectomy patients from the US third-party payer. Methods A Markov microsimulation model was developed to compare the cost and efficacy of berberine to no intervention, colonoscopy, and the combination of berberine and colonoscopy in postpolypectomy patients. Results After simulating 1 million patients, the study found that colonoscopy alone had a mean cost of $16,391 and mean quality-adjusted life-years (QALYs) of 16.03 per patient, whereas adding berberine slightly reduced the mean cost to $15,609 with a mean QALY of 16.05, making it a dominant strategy. Berberine therapy alone was less effective than colonoscopy alone, with a higher mean cost of $37,480 and a mean QALY of 15.32 per patient. However, berberine therapy was found to be a dominant strategy over no intervention. Conclusions Adding berberine to colonoscopy is the most cost-saving and effective approach for postpolypectomy patients. For patients who refuse or have limited access to colonoscopy, berberine alone is likely to be a dominant strategy compared to no intervention.

16.
RSC Adv ; 13(23): 15616-15623, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37228673

RESUMO

Titanium alloy, as a recognized difficult-to-cut material, places higher demands on the performance of cutting tools. Compared with the mainstream cemented carbide tools, PcBN tools have a higher life and better machining performance. In this paper, a new type of cubic boron nitride superhard tool was prepared by introducing Y2O3-stabilized ZrO2 (YSZ) under high temperature and high pressure (1500 °C, 5.5 GPa), and the effect of the variation of YSZ addition on the mechanical properties of the tool was systematically analyzed, and the cutting performance of the tool was also analyzed by cutting TC4. It was found that a small amount of YSZ addition, which generated a sub-stable t-ZrO2 phase during the sintering process, could improve the mechanical properties of the tool and increase its cutting life. When YSZ was added at 5 wt%, the flexural strength and fracture toughness of the composites reached the maximum values of 637.77 MPa and 7.18 MPa m1/2, while the cutting life of the tools reached the maximum value of 2615.81 m. And when YSZ was added at 2.5 wt%, the hardness of the material reached the maximum value of 43.62 GPa.

17.
Materials (Basel) ; 16(11)2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37297065

RESUMO

In this research, we report the synthesis of Si-TmC-B/PCD composites using Si, B, and transition metal carbide particles (TmC) as binders at high pressure and high temperature (HPHT method, 5.5 GPa and 1450 °C). The microstructure, elemental distribution, phase composition, thermal stability, and mechanical properties of PCD composites were systematically investigated. The Si-B/PCD sample is thermally stable in air at 919 °C. The initial oxidation temperature of the PCD sample with ZrC particles is as high as 976 °C, and it also has a maximum flexural strength of 762.2 MPa, and the highest fracture toughness of 8.0 MPa·m1/2.

18.
Chem Commun (Camb) ; 59(17): 2457-2460, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36752094

RESUMO

The complexation between tiara[5]arene (T[5]) and silver trifluoroacetate affords a binuclear metallo-pseudorotaxane on account of multiple endo-cavity AgI η2-arene interactions. Furthermore, two such enantiomeric [(CF3CO2Ag)2⊂T[5]] complexes are bridged by an extra (CF3CO2Ag)2 dimer through exo-wall AgI η2-arene coordination, resulting in a unique handcuff metallo-bis-pseudorotaxane structure in the solid state.

19.
Int J Biol Macromol ; 246: 125584, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37391002

RESUMO

Canine distemper virus (CDV) is an economically important virus responsible for canine distemper (CD), a highly contagious disease that afflicts various animal species worldwide. The hemagglutinin (H) protein is the major neutralizing target of virus. Therefore, it is often considered as immunogen to prepare neutralizing antibodies. The accurate identification of neutralizing epitope will provide important antigenic information and extend the knowledge of mechanisms of virus neutralization. In this study, we generated a neutralizing monoclonal antibody (mAb) 4C6 against CDV H protein, and defined the minimal linear epitope 238DIEREFDT245, which was highly conserved in America-1 genotype of CDV strains (vaccines). The mAb 4C6 could not react with a CDV strain that had two substitutions of D238Y and R241G in the epitope, which appeared in most CDV strains of the other genotypes. Besides, a few different amino acid mutations in the epitope were also included. Collectively, the epitope 238DIEREFDT245 was variable in the other genotypes of CDV strains. The epitope 238DIEREFDT245 was exposed to the surface of CDV H protein, showing good antigenicity. These data will provide insights into structure, function and antigenicity of H protein and lay the foundation for the development of diagnostic technologies and vaccine design for CDV.


Assuntos
Vírus da Cinomose Canina , Vacinas , Animais , Epitopos/genética , Vírus da Cinomose Canina/genética , Anticorpos Monoclonais , Genótipo , Filogenia
20.
Biol Trace Elem Res ; 201(1): 250-259, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35076866

RESUMO

Almost all selenogenes are expressed in the testis, and those have the highest and constant expressions will be the primary candidates for functional analysis of selenium (Se) in male reproduction. This study aimed to profile the mRNA expressions of the testis-abundant selenogenes of rat models in responses to growth and dietary Se concentrations. Forty-eight weaning SD male rats were fed Se deficient basal diet (BD) for 5 weeks and then randomly grouped (n = 12/group) for being fed BD or BD plus 0.25, 3, or 5 mg Se/kg for 4 more weeks before sacrifice. Abundances of selenogenomic mRNAs in the liver and testis were determined with relative qPCR and those of the testis-abundant selenogenes in 13 kinds of tissues were assayed with a molecular beacon-based qPCR. Spatiotemporal expressions of rat selenogenome were also analyzed with the RNA-Seq transcriptomic data published by NCBI. mRNA abundances of glutathione peroxidase 4 (Gpx4), nuclear Gpx4 (nGpx4), selenoprotein V (Selenov), and thioredoxin reductase 3 (Txnrd3) in the testis were significantly higher than that in any other tissues (P < 0.05). Moreover, testicular mRNA abundances of Gpx4, Selenov, and Txnrd3 were not affected by levels of dietary Se supplementation (P > 0.05), and much higher at 6-21 weeks old than at 2 and 104 weeks old (P < 0.05). The result showed that Gpx4, Selenov, and Txnrd3 were most highly expressed in the testis of rats especially at reproductive ages and resistant to the impact of dietary Se levels, which suggested their specific importance in male reproduction.


Assuntos
Selênio , Testículo , Animais , Masculino , Ratos , Glutationa Peroxidase/metabolismo , Fígado/metabolismo , Reprodução , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Selênio/metabolismo , Selenoproteínas/genética , Selenoproteínas/metabolismo , Testículo/metabolismo
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