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1.
Reprod Toxicol ; 106: 42-50, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34626775

RESUMO

Microplastics (MPs), which are emerging as a new type of environmental pollutants, have raised great concerns regarding their threats to human health. A successful pregnancy depends on the sophisticated regulation of the maternal-fetal immune balance, but the risks of polystyrene MP (PS-MP) exposure in early pregnancy remain unclear. In this study, we exposed the C57BL/6-mated BALB/c mice to PS-MP particles and used the flow cytometry to explore threats towards the immune system. Herein, the allogeneic mating murine model showed an elevated embryo resorption rate with a 10 µm PS-MP particle exposure during the peri-implantation period. Both the number and diameter of uterine arterioles decreased, which might reduce the uterine blood supply. Moreover, the percentage of decidual natural killer cells was reduced, whereas the helper T cells in the placenta increased. In addition, the M1/M2 ratio in macrophages reversed significantly to a dominant M2-subtype. Lastly, the cytokine secretion shifted towards an immunosuppressive state. Overall, our results demonstrated that PS-MPs have the potential to cause adverse effects on pregnancy outcomes via immune disturbance, providing new insights into the study of reproductive toxicity of MP particles in the human body.

2.
ACS Appl Mater Interfaces ; 13(39): 46225-46232, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34553591

RESUMO

To date, two-dimensional (2D) and three-dimensional (3D) metal organic frameworks (MOFs) have been promising materials for applications in electrocatalysis, separation, and sensing. However, the exploration of a simple method for simultaneous fabrication of 2D/3D MOFs on a surface remains challenging. Herein, a one-step and in situ electrosynthesis strategy for fabrication of 2D Hemin-bridged MOF sheets (Hemin-MOFs) or 2D/3D Zn(II)-MOF hybrid nanocomposites on an electrode is reported. It exhibits varied morphologies at different electrodeposition times and attains a 2D/3D complex morphology by adding 1,3,5-benzenetricarboxylic acid (H3BTC) as an organic ligand. The morphology and size of 2D Hemin-MOFs are important factors that influence their performance. Since Pt nanoparticles (PtNPs) are grown on 2D Hemin-MOF sheets, this composite can serve as the peroxidase mimics and PtNPs can act as an anchor to capture the antibody. Therefore, this hybrid nanosheet-modified electrode is used as an electrochemical sensing platform for ultrasensitive pig immunoglobulin G (IgG) and the surface-protective antigen (Spa) protein of Erysipelothrix rhusiopathiae immunodetection. Moreover, this work provides a new avenue for the electrochemical synthesis of 2D/3D MOF hybrid nanocomposites with a high surface area and biomimetic catalysts.

3.
Molecules ; 26(15)2021 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-34361602

RESUMO

Repairs of bone defects caused by osteoporosis have always relied on bone tissue engineering. However, the preparation of composite tissue engineering scaffolds with a three-dimensional (3D) macroporous structure poses huge challenges in achieving osteoconduction and osteoinduction for repairing bone defects caused by osteoporosis. In the current study, a three-dimensional macroporous (150-300 µm) reduced graphene oxide/polypyrrole composite scaffold modified by strontium (Sr) (3D rGO/PPY/Sr) was successfully prepared using the oxygen plasma technology-assisted method, which is simple, safe, and inexpensive. The findings of the MTT assay and AO/EB fluorescence double staining showed that 3D rGO/PPY/Sr has a good biocompatibility and effectively promoted MC3T3-E1 cell proliferation. Furthermore, the ALP assay and alizarin red staining showed that 3D rGO/PPY/Sr increased the expression levels of ALP activity and the formation of calcified nodules. The desirable biocompatibility, osteoconduction, and osteoinduction abilities, assure that the 3D macroporous rGO/PPY/Sr composite scaffold offers promising potential for use in the repair of bone defects caused by osteoporosis in bone tissue engineering.


Assuntos
Materiais Biocompatíveis/química , Osteoporose/terapia , Engenharia Tecidual/métodos , Tecidos Suporte/química , Animais , Linhagem Celular , Grafite/química , Camundongos , Osteoblastos , Polímeros/química , Impressão Tridimensional , Pirróis/química , Estrôncio/química
4.
Molecules ; 26(16)2021 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-34443680

RESUMO

Effect of temperature and pH on the interaction of curcumin with ß-casein was explored by fluorescence spectroscopy, ultraviolet-visible spectroscopy and molecular dynamics simulation. The spectroscopic results showed that curcumin could bind to ß-casein to form a complex which was driven mainly by electrostatic interaction. The intrinsic fluorescence of ß-casein was quenched by curcumin through static quenching mechanism. The binding constants of curcumin to ß-casein were 6.48 × 104 L/mol (298 K), 6.17 × 104 L/mol (305 K) and 5.73 × 104 L/mol (312 K) at pH 2.0, which was greater than that (3.98 × 104 L/mol at 298 K, 3.90 × 104 L/mol at 305 K and 3.41 × 104 L/mol at 312 K) at pH 7.4. Molecular docking study showed that binding energy of ß-casein-curcumin complex at pH 2.0 (-7.53 kcal/mol) was lower than that at pH 7.4 (-7.01 kcal/mol). The molecular dynamics simulation study showed that the binding energy (-131.07 kJ/mol) of ß-casein-curcumin complex was relatively low at pH 2.0 and 298 K. α-Helix content in ß-casein was decreased and random coil content was increased in the presence of curcumin. These results can promote a deep understanding of interaction between curcumin and ß-casein and provide a reference for improving the bioavailability of curcumin.


Assuntos
Caseínas/farmacologia , Curcumina/farmacologia , Simulação de Dinâmica Molecular , Análise Espectral , Caseínas/química , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Imageamento Tridimensional , Simulação de Acoplamento Molecular , Ligação Proteica , Estrutura Secundária de Proteína , Homologia Estrutural de Proteína , Termodinâmica
5.
J Biotechnol ; 337: 24-34, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-34197821

RESUMO

A thermostable T1 lipase from Geobacillus zalihae exhibits broad substrate specificity and good potential application in fats and oils. However, structural insight into the enzyme against substrates is poorly understood at the molecular level. Herein, the study aimed to examine interactions between a mutant T1 lipase (Mut-T1 lipase) and selected fatty acids (caprylic, myristic, stearic, oleic, linoleic and linolenic acids) by performing molecular docking and molecular dynamics (MD) simulation. The structure of Mut-T1 lipase obtained by homology modeling was reliable for molecular docking and MD simulation. Molecular docking revealed that Mut-T1 lipase showed low binding affinity for caprylic acid (-4.97 kcal/mol) compared to the other fatty acids (-5.65 to -6.88 kcal/mol). However, the conformation of Mut-T1 lipase-caprylic acid complex was comparably stable during the simulation, in terms of less root-mean square fluctuation. Besides, solvent accessible surface area value of Mut-T1 lipase-fatty acid complexes decreased with increasing chain length of fatty acid. van der Waals interactions were requisite in maintaining complex stability during the binding process. This work provides structural insight into interactions between the lipase and the fatty acids, which will facilitate design and applications of new mutants of T1 lipase in modifying fats and oils.


Assuntos
Ácidos Graxos , Simulação de Dinâmica Molecular , Geobacillus , Lipase/genética , Lipase/metabolismo , Simulação de Acoplamento Molecular
6.
Comp Immunol Microbiol Infect Dis ; 77: 101669, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34116388

RESUMO

Approximately 15 % of clinically recognized pregnancies end in miscarriage. To explore the vaginal microbiota profile in women diagnosed with early pregnancy miscarriage (including missed miscarriage [M] or empty-sac miscarriage [E]), the microbial community structure in vaginal fluid was evaluated by Illumina MiSeq sequencing of the 16S rRNA gene V4 region and compared with that in women with normal pregnancy (P). Taxa identified in samples from the P, E, and M groups formed distinct clusters. The M group had the highest bacterial species richness and diversity, with lower Lactobacillus levels and higher Bacteroides, Halomonas, Miscellaneous-Crenarchaeota, Bacillus, Staphylococcus, Escherichia/Shigella, and Acetobacter levels than in the other two groups. The vaginal community-state types differed significantly among the three groups (P = 0.02) but were similar between the P and E groups (P = 0.21). Moreover, we identified an optimal marker set composed of 12 operational taxonomic units based on a random forest model that distinguished the M and P groups, with areas under the receiver-operating characteristic curve of 86.76 % and 93.33 % in the training and test groups, respectively. In conclusion, this study highlights that patients with early pregnancy miscarriage had a significantly different vaginal microbiota profile. Microbial markers analyzed by RT-qPCR may be applied for the etiological diagnosis of miscarriage. Further studies should be performed to elucidate the possible mechanism of special strains affecting miscarriage during early pregnancy.


Assuntos
Aborto Animal , Microbiota , Animais , Feminino , Lactobacillus/genética , Gravidez , RNA Ribossômico 16S/genética , Vagina
7.
Sci Total Environ ; 787: 147660, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34004543

RESUMO

Robinia pseudoacacia L., a pioneer woody legume grown in mining areas, has been recognized as a remarkable accumulator of various heavy metals. Compared with other hazardous heavy metals (HMs), it is of low capacity in accumulating Cd, which, as a result, may hinder the phytoremediation efficiency. To enhance R. pseudoacacia's uptake efficiency of Cd, the individual effects of various rhizobia and arbuscular mycorrhizal fungi have been reported, however, the combined influence of endophytes and biochar receives little attention. In the current study, a Cd-adsorbing endophyte Enterobacter sp. YG-14 was inoculated to R. pseudoacacia, and its extraordinary effect on increasing R. pseudoacacia's Cd uptake was found, which was ascribed to the reinforced root Cd chelation by the strain through secreting siderophores/LMWOAs. Further, P-enriched sludge biochar was applied along with YG-14 to form a combined biochar-endophyte-accumulator system, in which biomineralization were reinforced (i.e. CdCO3 and Cd2P2O7 were generated), as the total and acid-soluble Cd in rhizosphere were reduced by 61.75% and 69.01% respectively, and soil's bacterial diversity was further improved with diversified N2-fixing microbial biomarkers. Multiple synergistic effects (E > 0) were also found, with the optimum performance on plant growth parameters (increased by 39.61%-561.91%) in comparison to the control group. Moreover, the system exhibited a preferable Cd phytostabilization capacity with the highest increase (81.42%) in Cd accumulation and a significant reduction (72.73%) in Cd root-to-shoot translocation.


Assuntos
Robinia , Poluentes do Solo , Biodegradação Ambiental , Cádmio/análise , Carvão Vegetal , Endófitos , Enterobacter , Rizosfera , Esgotos , Solo , Poluentes do Solo/análise
8.
Food Chem ; 360: 129952, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34000632

RESUMO

This study explored the effects of ß-glucan and various processing methods on the digestion of hulless barley starch in vitro. The whole hulless barley showed significantly lower starch digestibility compared to that hydrolyzed by ß-glucanase, indicating that ß-glucan had inhibitory effects on starch digestion. However, ß-glucan slightly accelerated the hydrolysis of extracted starch. Microscope observations of grains and flours revealed that the inhibitory effects of ß-glucan benefited from the integral cellular structure of hulless barley. Besides, the hulless barley processed through flaking-roasting and stir-frying exhibited significantly lower starch digestibility (41.5% and 38.9%, respectively) and considerable intact cells and starch granules. The hulless barley processed by steam flash-explosion showed moderate starch digestibility (48.2%), which may be attributed to the encapsulation of starch-protein-ß-glucan complexes. This elucidated the possible mechanism of ß-glucan limiting the hydrolysis of hulless barley starch and provided useful direction to produce hulless barley products with desirable starch digestibility.


Assuntos
Hordeum/química , Amido/química , beta-Glucanas/química , Digestão , Hidrólise , Técnicas In Vitro , Viscosidade
9.
BMC Surg ; 21(1): 164, 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33765960

RESUMO

BACKGROUND: Prosthetic valve detachment is not rare after aortic valve replacement in Behcet's disease. However, destruction of the intervalvular fibrous body (IFB) due to Behcet's disease was rarely reported. CASE PRESENTATION: We report a case of 30 year-old woman, with valve detachment and IFB separation. The patient received aortic valve replacement three months ago. Her medical history included recurrent oral ulcers and cutaneous lesions. Finally, reoperation was performed and peri-operative steroid therapy was carried out. CONCLUSIONS: The case presented a rare complication of valve detachment in Behcet's disease.


Assuntos
Valva Aórtica , Síndrome de Behçet , Próteses Valvulares Cardíacas , Falha de Prótese , Adulto , Valva Aórtica/cirurgia , Síndrome de Behçet/complicações , Síndrome de Behçet/diagnóstico , Feminino , Próteses Valvulares Cardíacas/efeitos adversos , Humanos
10.
Reproduction ; 161(6): 623-632, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33784242

RESUMO

Preeclampsia is a gestational hypertensive disease; however, preeclampsia remains poorly understood. Bioinformatics analysis was applied to find novel genes involved in the pathogenesis of preeclampsia and identified CLDN1 as one of the most differentially expressed genes when comparing patients with preeclampsia and healthy controls. The results of the qRT-PCR, Western blotting and immunohistochemistry experiments demonstrated that CLDN1 was significantly downregulated in the chorionic villi in samples from patients with preeclampsia. Furthermore, knockdown of CLDN1 in HTR-8/SVneo cells resulted in the inhibition of proliferation and induction of apoptosis, and overexpression of CLDN1 reversed these effects. In addition, RNA-seq assays demonstrated that the gene BIRC3 is potentially downstream of CLDN1 and is involved in the regulation of apoptosis. Knockdown of CLDN1 confirmed that the expression level of BIRC3 was obviously decreased and was associated with a significant increase in cleaved PARP. Interestingly, the apoptotic effect in CLDN1 knockdown cells was rescued after BIRC3 overexpression. Overall, these results indicate that a decrease in CLDN1 inhibits BIRC3 expression and increases cleaved PARP levels thus participating in the pathogenesis of preeclampsia.

11.
J Oleo Sci ; 70(2): 227-236, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33456003

RESUMO

n-3 polyunsaturated fatty acids (PUFA)-rich triacylglycerols (TAG) with many beneficial effects are still difficult to be synthesized efficiently and rapidly by current synthetic techniques. This study reports the fatty acid specificity of immobilized MAS1 lipase and its efficient synthesis of n-3 PUFA-rich TAG by esterification of glycerol with n-3 PUFA in natural deep eutectic solvents (NADES) systems. Immobilized MAS1 lipase showed the highest preference for capric acid [C10:0, the highest specificity constant (1/α)=1] whereas it discriminated strongly against docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) due to their lowest specificity constants (1/α=0.19 and 0.2). Moreover, the highest n-3 PUFA-rich TAG content (55.8%) with similar n-3 PUFA composition to the substrate was obtained in choline chloride/glycerol (CG) system. There was a 1.38-fold increase of TAG content in CG system compared with that in the solvent-free system. Interestingly, immobilized MAS1 lipase exhibited no regiospecificity in the solvent-free and various NADES systems. Besides, the potential reaction mechanism of immobilized MAS1 lipase-catalyzed esterification of glycerol with n-3 PUFA in NADES systems was described. It was found that the use of NADES as solvents could greatly enhance TAG content, and make it easy to separate the product. These results indicated that immobilized MAS1 lipase is a promising biocatalyst for the efficient synthesis of n-3 PUFA-rich TAG by esterification of glycerol with n-3 PUFA in NADES systems.


Assuntos
Enzimas Imobilizadas/química , Ácidos Graxos Ômega-3/química , Lipase/química , Solventes/química , Triglicerídeos/síntese química , Catálise , Colina/química , Ácidos Decanoicos , Ácidos Docosa-Hexaenoicos , Ácido Eicosapentaenoico , Esterificação , Glicerol/química , Triglicerídeos/química
12.
Bioprocess Biosyst Eng ; 44(3): 575-584, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33216225

RESUMO

This study reports the properties of immobilized MAS1-H108A lipase from marine Streptomyces sp. strain W007 on XAD1180 resin and its application in the synthesis of n-3 polyunsaturated fatty acids (PUFA)-rich triacylglycerols (TAG) for the first time. It was found that the optimal temperature and pH for both immobilized MAS1-H108A lipase and free lipase MAS1-H108A were 70 °C and 7.0, respectively. However, immobilized MAS1-H108A lipase exhibited higher thermostability when compared with free lipase MAS1-H108A. It was also interesting that both immobilized MAS1-H108A lipase and free lipase MAS1-H108A showed no regiospecificity in the hydrolysis of triolein. Subsequently, immobilized MAS1-H108A lipase and free lipase MAS1-H108A were employed to catalyze glycerolysis of n-3 PUFA-rich ethyl esters (EE) and esterification of n-3 PUFA with glycerol under vacuum in the solvent-free system. The results showed that n-3 PUFA-rich TAG were synthesized efficiently by non-regiospecific immobilized MAS1-H108A lipase and TAG contents separately reached 92.07% and 76.13% during the esterification and glycerolysis reactions, which were significantly higher than those (71.82% and 39.62%, respectively) obtained by free lipase MAS1-H108A. Besides, TAG exhibited similar n-3 PUFA composition to the substrate. These findings indicated that non-regiospecific immobilized MAS1-H108A lipase is a promising and efficient biocatalyst for the industrial synthesis of n-3 PUFA-rich TAG.

13.
Mol Cell Endocrinol ; 518: 111028, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32911017

RESUMO

BACKGROUND: MiR-142-3p has been shown to be suppressed in obese patients, while the underlying regulatory mechanism is unclear. METHODS: Body shape indexes as well as peripheral blood for biochemical parameter analysis were obtained from obese and healthy subjects. When 3T3-L1 cells were induced to differentiate, miR-142-3p expression was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The effects of miR-142-3p on triglyceride (TG) and adipogenic differentiation-related genes during the adipogenic differentiation of 3T3-L1 cells were detected by transfection, Oil Red O staining, and Western blot. The targeting relationship between miR-142-3p and Krueppel-like transcription factor 9 (KLF9) was verified by TargetScan and dual-luciferase experiment. The specific regulatory effects of miR-142-3p on cell adipogenic differentiation and autophagy were analyzed by rescue experiments. In vivo experiments further validated the results of in vitro experiments through obese mouse models. RESULTS: Obesity-marked biochemical indicators increased whereas high density lipoprotein and miR-142-3p decreased in obese patients. The content of miR-142-3p gradually decreased with cell lipid differentiation. Overexpression of miR-142-3p reduced TG deposition in cells by down-regulating lipid formation and fatty acid synthesis genes and up-regulating fatty acid oxidation genes. KLF9 targeting miR-142-3p was suppressed by miR-142-3p. KLF9 overexpression partially reversed the inhibitory effect of miR-142-3p mimic on adipogenic differentiation and the expressions of autophagy related-genes in 3T3-L1 cells. MiR-142-3p overexpression also inhibited fat cell differentiation and autophagy in obese mice. CONCLUSION: Overexpressed miR-142-3p inhibited adipogenic differentiation and autophagy through targeting KLF9.

15.
Int J Biol Macromol ; 156: 494-503, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32304788

RESUMO

This study aimed to simultaneously enhance the strength and ductility of films by adding graphene oxide (GO) into the sodium alginate (SA)-gelatin film system to prepare SA-gelatin-GO ternary composite films. The effects of the SA/gelatin weight ratio and the GO content on the morphology, structural, mechanical, hydrophobic, water vapor barrier, hygroscopic, and optical properties of composite films were investigated. Results showed that tensile strength and elongation at break values of the composite film with 0.5% GO content were significantly improved from 37.00 to 48.01 MPa and 20.19% to 25.75%, respectively, compared with the SA-gelatin film without GO, suggesting GO with the content of 0.5% simultaneously enhance the strength and ductility of the SA-gelatin film, which was due to the interaction of hydrogen bonds and the good dispersibility of GO in the film matrix. The surface hydrophobicity of composite films increased first and then decreased with increasing GO content. In addition, the hygroscopicity of composite films reduced due to the GO addition, especially when the GO content was 0.25%. The SA-gelatin-GO ternary composite films provide a good select for food packaging materials, especially the materials that require high strength and fine ductility.


Assuntos
Alginatos/química , Gelatina/química , Grafite/química , Resistência à Tração , Condutividade Térmica , Interações Hidrofóbicas e Hidrofílicas , Permeabilidade , Análise Espectral , Vapor , Água/química
16.
Waste Manag ; 108: 1-12, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32334329

RESUMO

Insulating strategies are indispensable for laboratory-scale composting reactors, however, current insulation methods interfere with the aerobic fermentation behaviors related to composting. To address this issue, a centre-oriented real-time temperature compensation strategy was designed in this study. Five 9 L reactors (R1-R5) with different insulation strategies were used for the co-composting of dewatered sludge and Phragmites australis and compared. The process performance was assessed by monitoring the temperature, O2 and CO2 emissions, the physical-chemical properties of the composting materials were evaluated by measuring the organic matter (OM), carbon nitrogen ratio (C/N), pH, electrical conductivity (EC), and fluorescence excitation-emission matrix (EEM) spectra. And a 16S rDNA analysis was used to quantify the evolution of bacterial community. The main findings are as follows. Compared with R1 as a control, the insulating strategies can increase the maximum temperature and prolong the thermophilic phase of composting. Comparing R1 and R3 showed that real-time temperature compensation can better restore the real fermentation of the compost. The results showed that R5 had the best composting effect, reaching 69.8 °C, which was 25.1%, 29.7%, 19.3%, and 17.3% higher than R1, R2, R3, and R4, respectively, and remaining in the thermophilic phase for 4.24 d, which is 1.4, 1.5, 1.3, and 0.2 times longer than R1, R2, R3, and R4, respectively. Furthermore, it can significantly reduce the temperature difference between the centre and edge of the reactor, which improved the composting material allocation efficiency and composting process control accuracy, further providing a basis for the actual full-scale composting operation.


Assuntos
Compostagem , Bactérias , Nitrogênio , Esgotos , Solo , Temperatura
17.
Cell Death Dis ; 11(2): 119, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-32051396

RESUMO

A successful pregnancy requires sophisticated regulation of uterine microenvironment to guarantee the existence of semi-allogeneic conceptus without immune rejection. T follicular regulatory (Tfr) cells exert a suppressive effect on Tfh-cell expansion, B-cell response, and antibody production. Although accumulating evidence has demonstrated that dysregulations of Tfr cells can bring on various immunological diseases, their immunomodulatory roles during pregnancy still remain unheeded. Herein, we introduced an allogeneic normal-pregnant mouse model and found that CD4+CXCR5hiPD-1hiFoxp3+ Tfr cells were preferentially accumulated in the uterus at mid-gestation and displayed a distinct phenotype. In addition, the absence of PDL1 resulted in increased fetal resorption by favoring Tfr cells accumulation and upregulating PD-1 expression on these cells. However, PDL1 blockade affected neither the ratio of Tfh/Tfr cells nor the maturation and differentiation of B cells. Overall, our results are the first to present a correlation of Tfr cells accumulation with healthy allogeneic pregnancy and PDL1 blockade-induced miscarriage, and to indicate that appropriate assembly of Tfr cells is important for pregnancy maintenance. Since blockade of PD-1-PDL1 pathway leads to more Tfr cells and fetal losses, the reproductive safety must be taken into consideration when PD-1/PD-L1 checkpoint blockade immunotherapy is used in pregnancy.


Assuntos
Aborto Espontâneo/induzido quimicamente , Linfócitos B/efeitos dos fármacos , Antígeno B7-H1/antagonistas & inibidores , Reabsorção do Feto/induzido quimicamente , Inibidores de Checkpoint Imunológico/toxicidade , Células T Auxiliares Foliculares/efeitos dos fármacos , Linfócitos T Reguladores/efeitos dos fármacos , Útero/efeitos dos fármacos , Aborto Espontâneo/imunologia , Aborto Espontâneo/metabolismo , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Antígeno B7-H1/metabolismo , Feminino , Reabsorção do Feto/imunologia , Reabsorção do Feto/metabolismo , Idade Gestacional , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fenótipo , Gravidez , Receptor de Morte Celular Programada 1/metabolismo , Medição de Risco , Transdução de Sinais , Células T Auxiliares Foliculares/imunologia , Células T Auxiliares Foliculares/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Útero/imunologia , Útero/metabolismo
18.
Anal Chem ; 92(2): 1890-1897, 2020 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-31920079

RESUMO

In this work, fullerenols were found to be able to enhance the ECL signals of the luminol and H2O2 system and were employed for the first time as a reducing, catalyzing, and stabilizing agent in the one-step fast synthesis of fullerenols@AuNPs in only 5 min. First, the prepared fullerenols@AuNPs were applied to fabricate a label-free immunosensor for the detection of human cardiopathy biomarker (cardiac troponin I, cTnI). Second, using the fullerenols@AuNPs as biolabels to establish a sandwich-type immunosensor and catalyzing in situ copper-stained reaction to generate Cu particles capped on the fullerenols@AuNPs, and then a novel electrochemical stripping chemiluminescent (ESCL) method was developed for detection of cTnI and IgG with about 20 times more sensitive than the former one. At the process of ESCL detection, Cu2+was stripped from Cu@fullerenols@AuNPs with significant increase of the ECL signals. This can be attributed to the fact that the fullerenols@AuNPs nanoparticles and the Cu2+ have excellent conductivity and could facilitate the decomposition of H2O2 to generate various reactive oxygen species (ROSs), thereby accelerating the ECL process. Both immunosensors show high sensitivity and selectivity to cTnI and IgG detection with a wide linear range from fg/mL to ng/mL and the low limits of detection down to fg/mL for cTnI and IgG, respectively.


Assuntos
Fulerenos/química , Imunoglobulina G/análise , Nanopartículas Metálicas/química , Troponina I/análise , Anticorpos Imobilizados/imunologia , Cobre/química , Técnicas Eletroquímicas/métodos , Ouro/química , Humanos , Peróxido de Hidrogênio/química , Imunoensaio/métodos , Imunoglobulina G/imunologia , Limite de Detecção , Luminescência , Medições Luminescentes/métodos , Luminol/química , Troponina I/imunologia
20.
Analyst ; 145(3): 873-879, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-31845932

RESUMO

In this work, an Au-Ag alloy nanourchin (Au-Ag alloy NU) based electrochemiluminescent (ECL) sensor for the measurement of cardiac troponin I (cTnI) was developed. The as-prepared Au-Ag alloy NUs exhibited higher specific surface area and better conductivity owing to their unique urchin-like morphology, which resulted in excellent electrocatalytic activity towards H2O2 in the luminol-H2O2 ECL system. We have found that the Au-Ag alloy NUs could enhance the ECL signal in the luminol-H2O2 solution. Based on these facts, a facile and label-free ECL immunosensor has been constructed for the analysis of cTnI, a cardiac biomarker, with a wide linear range of 3.5 pg mL-1-350 µg mL-1. This novel ECL immunosensor has good stability and reproducibility, showing potential application in clinical diagnostics. In addition, a non-enzymatic electrochemical sensor for H2O2 was also fabricated, with a wide linear detection range of 100 nM-200 µM, a low limit of detection of 45 nM and a fast response time (less than 2 s).

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