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1.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(9): 1015-1023, 2020.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-33051414

RESUMO

OBJECTIVES: To investigate the effect of ligand-receptor interaction of osteopontin (OPN)-CD44 on the expression of hyaluronic acid (HA) in the cultured human knee osteoarthritis (OA) chondrocytes via interfering the reaction between OPN and CD44 ligand-receptor. METHODS: The OA chondrocytes and normal chondrocytes were obtained from knee joint cartilage tissues in the patients with knee OA and malignant tumor respectively. The normal chondrocytes and OA chondrocytes were detected and analyzed, and then the intervention analysis of OA chondrocytes was carried out. The OA chondrocytes were divided into 4 groups: a negative control group, which was cultured with complete medium without any molecular intervention reagent; an OPN intervention group, which was cultured with recombinant human OPN (rhOPN) for 24 hours; a CD44 blocking group, which were pretreated with CD44 receptor specific antagonist for 1 hour to block the binding of OPN-CD44, and then treated with rhOPN for 23 hours; a CD44 homotype group, which was pretreated with CD44 for 1 hour and then treated with rhOPN for 23 hours. In addition, the study for OPN-CD44 axis was also divided into 4 groups: an OA-negative control group (OA-NC group), a si-OPN intervention group, a rhOPN intervention group, and a rhOPN + CD44 antibody (Ab) group. Western blotting, real-time PCR, and enzyme linked immunosorbent assay (ELISA) were used to detect the protein and mRNA expression levels of OPN, CD44, hyaluronate synthase (HAS), and HA, respectively. RESULTS: The protein expression levels of OPN, CD44, and HAS1 and the secretion levels of HA in the OA chondrocytes were higher than those in the normal chondrocytes. Compared with the OPN intervention group, the expression levels of HAS1, HAS2, HAS3 and HA in the CD44 blocking group were lower than those in OPN intervention group (all P<0.05); but there was no significant difference in the expression levels of HAS1, HAS2, HAS3 and HA between the CD44 homotype group and the OPN intervention group (all P>0.05). The results of OPN-CD44 axis study showed that: compared with the OA-NC group, the expression of CD44 in the rhOPN intervention group was slightly lower, but the protein and mRNA levels of HAS1 were significantly increased (all P<0.05); compared with the OA-NC group, the expression of CD44 was up-regulated, but the protein and mRNA level of HAS1 were significantly inhibited in the si-OPN intervention group (all P<0.05); compared with the OA-NC group, the protein and mRNA levels of HAS1 in the rhOPN+CD44 Ab group were also significantly inhibited (all P<0.05). CONCLUSIONS: The OPN in OA chondrocytes can promote the expression of HAS1, and the OPN can stimulate the secretion of HAS and induce HA expression by reacting with CD44 ligand receptor. They constitute the axis of OPN/CD44/HAS1, which plays an important role in regulating the expression of HA in chondrocytes.


Assuntos
Ácido Hialurônico , Osteoartrite do Joelho , Osteopontina , Condrócitos , Humanos , Receptores de Hialuronatos/genética , Articulação do Joelho , Osteopontina/genética , Osteopontina/fisiologia
2.
ACS Sens ; 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33064465

RESUMO

Photoanode sensing platforms with remarkable photoelectrochemical (PEC) response and satisfying visible-light absorption have become the most promising detection systems. Nevertheless, their inevitable electrophilic character limits their expansion in the bioassay because of reductive substances in serum or other body fluids that can severely interfere with the photocurrent to be read. To solve it, a PEC platform-assembled dual-active electrode is designed to realize the separation of biological monitoring from the photoanode. The ferricyanide ([Fe(CN)6]3-)-mediated redox cycle is first proposed to meet the gain and loss electron requirements of the PEC system. It can avoid the self-reaction in the electrolyte caused by the addition of a traditional electron donor and acceptor, for instance, ascorbic acid and hydrogen peroxide. As a consequence, the traditional counter electrode (Pt wire) is replaced by Fe2O3/AgInS2 heterojunction, which can amplify the PEC response of the cathode to meet the requirement of trace analysis. An aptasensor fabricated by the above strategies exhibits convincing data for 17ß-estradiol (E2) detection from which a wide detection range is obtained in 10 fg/mL to 1 µg/mL with a detection limit of 2.74 fg/mL (S/N = 3). These advanced elements show a rosy prospect for environmental monitoring and point-of-care biomarker diagnosis.

3.
Food Funct ; 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33048099

RESUMO

Despite that colorectal cancer (CRC) is a severe global health problem, effective chemopreventive strategies against CRC are still lacking. Huang-qin tea (HQT), a healthy herbal tea, is prepared from the aerial parts of Scutellaria baicalensis Georgi and has been consumed in China for thousands of years. HQT contains abundant flavonoids, which display potent anticancer effects, but no research studies have investigated the cancer-preventive effects of HQT on CRC in vivo. Here, we found that HQT inhibits azoxymethane-induced aberrant crypt foci (ACF) formation in a preneoplastic colonic ACF rat model. The essential role of the gut microbiota in the chemopreventive effect of HQT on CRC in a pseudo-germ-free rat model was confirmed. Besides, HQT modulates inflammatory cytokine expression by significantly decreasing IL-1ß, IL-6, IL-10, and TNF-α expression, and elevating IFN-γ production. 16S rDNA sequencing analysis indicated that HQT regulated the gut microbiota by increasing the abundance of beneficial bacteria (Lachnoclostridium, Alistipes, Roseburia, and Lactococcus) and reducing the levels of Bacteroides, Parasutterella, and unidentified_Clostridiales. Fecal metabolomics showed that HQT modulated the AOM-induced metabolomic disorder, and these altered metabolites were almost involved in the lipid metabolic pathways. The Spearman correlation analysis revealed a correlation between the gut microbiota and fecal metabolites. Collectively, these results suggested that HQT exerted beneficial effects on host health by inhibiting inflammation, and by regulating the gut microbiota profile and certain metabolic pathways. In conclusion, HQT inhibits AOM-induced ACF formation by modulating the gut microbiota composition and improving metabolomic disorders, indicating the potential of HQT as a functional beverage candidate for the prevention and treatment of CRC.

4.
Viruses ; 12(10)2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-33007975

RESUMO

Grapevine leafroll-associated virus 1 (GLRaV-1) is a major pathogen associated with grapevine leafroll disease. However, the molecular mechanisms underlying GLRaV-1 interactions with plant cells are unclear. Using Agrobacterium infiltration-mediated RNA-silencing assays, we demonstrated that GLRaV-1 p24 protein (p24G1) acts as an RNA-silencing suppressor (RSS), inhibiting local and systemic RNA silencing. Electrophoretic mobility shift assays showed that p24G1 binds double-stranded 21-nucleotide small interfering RNA (siRNA), and that siRNA binding is required but not sufficient for its RSS activity. p24G1 localizes in the nucleus and can self-interact through its amino acid 10 to 210 region. Dimerization is needed for p24G1 interaction with importin α1 before moving to the nucleus, but is not required for its siRNA binding and RSS activity. Expression of p24G1 from a binary pGD vector or potato virus X-based vector elicited a strong hypersensitive response in Nicotiana species, indicating that p24G1 may be a factor in pathogenesis. Furthermore, p24G1 function in pathogenesis required its RSS activity, dimerization and nuclear localization. In addition, the region of amino acids 122-139 played a crucial role in the nuclear import, siRNA binding, silencing suppression and pathogenic activity of p24G1. These results contribute to our understanding of the molecular mechanisms underlying GLRaV-1 infection.

6.
Inflammation ; 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33044666

RESUMO

The inflammatory response involving interleukin-1ß (IL-1ß) has been thought to play an important role in the development of late-phase sepsis. However, in this study, we wanted to explore the possibility of using IL-1ß to improve the prognosis of sepsis by triggering local differentiation of bone marrow cells (BMCs) into regulatory dendritic cells (DCs) in vivo, thereby reversing the immune paralysis in late-phase sepsis. Sepsis mouse models were induced by cecal ligation and puncture (CLP) and lethal Escherichia coli O18 infection. Mice were injected intraperitoneally with IL-1ß after CLP and after the lethal infection. Septic BMCs and liver immune cells were isolated at 0, 3, 6, 9, and 14 days post-CLP. BMCs and liver cells isolated from septic mice treated with IL-1ß were adoptively transferred into CLP mice. GFP+-C57BL/6 parabiosis models were established. Serum IL-1ß levels were determined by enzyme-linked immunosorbent assay (ELISA) kit, and the number, ratio, and phenotype of immune cells were observed by flow cytometry. IL-1ß treatment improved the survival of sepsis and increased the numbers of BMCs and liver immune cells in septic mice. Moreover, IL-1ß stimulation increased the number and the percentage of CD11c-CD45RBhigh DCs in septic BM and liver. Adoptive transfer of septic BMCs, liver immune cells, and CD11c-CD45RBhigh DCs treated with IL-1ß into CLP mice attenuated sepsis. IL-1ß triggered the redistribution of CD11c-CD45RBhigh DCs as well as BMCs in parabiosis models. IL-1ß protects against sepsis by stimulating local proliferation and differentiation of BMCs into CD11c-CD45RBhigh DCs at immune organs and non-immune organs.

7.
Bioorg Chem ; 104: 104314, 2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-33011538

RESUMO

Small molecule accurate recognition technology (SMART) is an emerging method for the rapid structural prediction of major constituents from crude extracts and fractions. In the present study, a targeted isolation of an Elephantopus scaber extract by SMART resulted in the obtention of 15 new (1-15) and five known germacranolide sesquiterpenes (16-20). Their structures were assigned by extensively analyzing HRESIMS, NMR, X-ray crystallographic analyses, modified Mosher's method results, and quantum chemical calculate electronic circular dichroism (ECD) spectra. All germacranolide sesquiterpenes were screened to determine their inhibitory effects with two hepatoma cell lines (HepG2 and Hep3B), and compounds 14, 16, 18, 19 and 20 showed significant cytotoxic activities against the HepG2 (IC50, 3.3-9.9 µM) and Hep3B (IC50, 4.5-8.6 µM) cell lines. Further study suggested that 18 can induce the apoptosis of hepatoma cells via mitochondrial dysfunction.

8.
Mol Med Rep ; 22(5): 3895-3903, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33000225

RESUMO

Potassium­channel tetramerization-domain-containing 1 (KCTD1) mutations are reported to result in scalp­ear­nipple syndrome. These mutations occur in the conserved broad­complex, tramtrack and bric a brac domain, which is associated with inhibited transcriptional activity. However, the mechanisms of KCTD1 mutants have not previously been elucidated; thus, the present study aimed to investigate whether KCTD1 mutants affect their interaction with transcription factor AP­2α and their regulation of the Wnt pathway. Results from the present study demonstrated that none of the ten KCTD1 mutants had an inhibitory effect on the transcriptional activity of AP­2α. Co­immunoprecipitation assays demonstrated that certain mutants exhibited changeable localization compared with the nuclear localization of wild­type KCTD1, but no KCTD1 mutant interacted with AP­2α. Almost all KCTD1 mutants, except KCTD1 A30E and H33Q, exhibited differential inhibitory effects on regulating TOPFLASH luciferase reporter activity. In addition, the interaction region of KCTD1 to the PY motif (amino acids 59­62) in AP­2α was identified. KCTD1 exhibited no suppressive effects on the transcriptional activity of the AP­2α P59A mutant, resulting in Char syndrome, a genetic disorder characterized by a distinctive facial appearance, heart defect and hand abnormalities, by altered protein cellular localization that abolished protein interactions. However, the P59A, P60A, P61R and 4A AP­2α mutants inhibited TOPFLASH reporter activity. Moreover, AP­2α and KCTD1 inhibited ß­catenin expression levels and SW480 cell viability. The present study thus identified a putative mechanism of disease­related KCTD1 mutants and AP­2α mutants by disrupting their interaction with the wildtype proteins AP­2α and KCTD1 and influencing the regulation of the Wnt/ß­catenin pathway.

9.
BMC Med Genet ; 21(1): 196, 2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33032550

RESUMO

BACKGROUND: Juvenile polyposis syndrome (JPS) is a rare autosomal dominant hereditary disorder characterized by the development of multiple distinct juvenile polyps in the gastrointestinal tract with an increased risk of colorectal cancer. Germline mutations in two genes, SMAD4 and BMPR1A, have been identified to cause JPS. CASE PRESENTATION: Here, we report a germline heterozygous missense variant (c.299G > A) in exon 3 BMPR1A gene in a family with juvenile polyposis. This variant was absent from the population database, and concluded as de novo compared with the parental sequencing. Further sequencing of the proband's children confirmed the segregation of this variant with the disease, while the variant was also predicted to have damaging effect based on online prediction tools. Therefore, this variant was classified as likely pathogenic according to the American College of Medical Genetics and Genomics (ACMG) guidelines. CONCLUSIONS: Germline genetic testing revealed a de novo germline missense variant in BMPR1A gene in a family with juvenile polyposis. Identification of the pathogenic variant facilitates the cancer risk management of at-risk family members, and endoscopic surveillance is recommended for mutation carriers.

11.
Sci Rep ; 10(1): 16573, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33024176

RESUMO

How to convert heat energy into other forms of usable energy more efficiently is always crucial for our human society. In traditional heat engines, such as the steam engine and the internal combustion engine, high-grade heat energy can be easily converted into mechanical energy, while a large amount of low-grade heat energy is usually wasted owing to its disadvantage in the temperature level. In this work, for the first time, the generation of mechanical energy from both high- and low-temperature steam is implemented by a hydrophilic polymer membrane. When exposed to water vapor with a temperature ranging from 50 to 100 °C, the membrane repeats rolling from one side to another. In nature, this continuously rolling of membrane is powered by the steam, like a miniaturized "steam engine". The differential concentration of water vapor (steam) on the two sides of the membrane generates the asymmetric swelling, the curve, and the rolling of the membrane. In particular, results suggest that this membrane based "steam engine" can be powered by the steam with a relatively very low temperature of 50 °C, which indicates a new approach to make use of both the high- and low-temperature heat energy.

12.
Biotechnol Bioeng ; 2020 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-33038015

RESUMO

Cancer has always been a global problem, with more cases of cancer patients being diagnosed every year. Conventional cancer treatments, including radiotherapy, chemotherapy and surgery, are still unable to bypass their obvious limitations, and developing effective targeted therapies is still required. More than one century ago, the doctor William B. Coley discovered that cancer patients had tumor regression by injection of Streptococcus bacteria. The studies of cancer therapy using bacterial microorganisms are now very widespread. In particular, the facultative anaerobic bacteria Salmonella Typhimurium is widely investigated as it can selectively colonize different types of tumors, locally deliver various anti-tumor drugs, and inhibit tumor growth. The exciting anti-tumor efficacy and safety observed in animal tumor models prompted the well-known attenuated Salmonella bacterial strain VNP20009 to be tested in human clinical trials in the early 21st century. Regrettably, no patients showed significant therapeutic effects and even bacterial colonization in tumor tissue was undetectable in most patients. Salmonella bacteria are still considered as a promising agent or vehicle for cancer therapy. Recent efforts have been focused on the generation of attenuated bacterial strains with higher targeting for tumor tissue, and optimization of the delivery of therapeutic anti-tumor cargoes into the tumor microenvironment. This review will summarize new technologies or approaches that may improve bacteria-mediated cancer therapy. This article is protected by copyright. All rights reserved.

13.
Chin Med J (Engl) ; 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33009019

RESUMO

BACKGROUND: Accumulating evidence has revealed that circulating microRNAs (miRNAs) can serve as non-invasive biomarkers for cancer diagnosis. This study aimed to identify differentially expressed miRNAs in serum which might become potential biomarkers for non-invasive diagnosis of papillary thyroid carcinoma (PTC). METHODS: The experiment was carried out between 2015 and 2017. In the screening stage, the Exiqon miRNA quantitative real-time polymerase chain reaction (qPCR) panel was applied to select candidate miRNAs. In the following training, testing, and external validation stages, the serum samples of 100 patients and 96 healthy controls (HCs) were analyzed to compare the expression levels of the identified miRNAs. The areas under the receiver operating characteristic curves (AUCs) were calculated to assess the diagnostic value of the identified signature. RESULTS: Three miRNAs (miR-25-3p, miR-296-5p, and miR-92a-3p) in serum were consistently up-regulated in PTC patients compared with HCs. A three-miRNA panel was constructed by logistic regression analysis and showed better diagnostic performance than a single miRNA for PTC detection. The AUCs of the panel were 0.727, 0.771, and 0.862 for the training, testing, and external validation stage, respectively. Meanwhile, the panel showed stable capability in differentiating PTC patients from patients with benign goiters, with an AUC as high as 0.969. For further exploration, the three identified miRNAs were analyzed in tissue samples (23 PTC vs. 23 HCs) and serum-derived exosomes samples (24 PTC vs. 24 HCs), and the altered expression in the tumor also indicated their close relationship with PTC disease. CONCLUSION: We identify a three-miRNA panel in serum which might serve as a promising biomarker for PTC diagnosis.

14.
Anal Bioanal Chem ; 2020 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33009597

RESUMO

In this study, a simple and efficient strategy for the construction of hydrangea-like mesoporous WO3 nanoflowers templated using diblock copolymer PS119-PtBA129 was developed. The nanoflower shows good gas sensing properties, especially for 3-hydroxy-2-butanone (3H-2B), which is the signature metabolite of Listeria monocytogenes (L. monocytogenes). Therefore, the gas sensing of 3H-2B by hydrangea-like mesoporous WO3 nanoflowers can be used to detect L. monocytogenes. In the case of 25 ppm 3H-2B as target gas, the response (Ra/Rg) of the hydrangea-like mesoporous WO3 nanoflowers at 205 °C is 152, where Ra and Rg are the resistances of the sensing device in air and target gas, respectively, and the response and recovery times at 25 ppm are 25 s and 146 s, respectively. Schematic illustration of the formation of hydrangea-like mesoporous WO3 nanoflowers and its gas sensing implication.

15.
J Cell Mol Med ; 2020 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33009892

RESUMO

Glioblastoma (GBM) is a malignant intracranial tumour with the highest proportion and lethality. It is characterized by invasiveness and heterogeneity. However, the currently available therapies are not curative. As an essential environmental cue that maintains glioma stem cells, hypoxia is considered the cause of tumour resistance to chemotherapy and radiation. Growing evidence shows that immunotherapy focusing on the tumour microenvironment is an effective treatment for GBM; however, the current clinicopathological features cannot predict the response to immunotherapy and provide accurate guidance for immunotherapy. Based on the ESTIMATE algorithm, GBM cases of The Cancer Genome Atlas (TCGA) data set were classified into high- and low-immune/stromal score groups, and a four-gene tumour environment-related model was constructed. This model exhibited good efficiency at forecasting short- and long-term prognosis and could also act as an independent prognostic biomarker. Additionally, this model and four of its genes (CLECL5A, SERPING1, CHI3L1 and C1R) were found to be associated with immune cell infiltration, and further study demonstrated that these four genes might drive the hypoxic phenotype of perinecrotic GBM, which affects hypoxia-induced glioma stemness. Therefore, these might be important candidates for immunotherapy of GBM and deserve further exploration.

16.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 5992-5995, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33019337

RESUMO

Cuffless and continuous blood pressure (BP) measurement using wearable devices is of great clinical value and health monitoring importance. Pulse arrival time (PAT) based technique was considered as one of the most promising methods for this purpose. Considering the dynamic and nonlinear relationship between BP, PAT and other cardiovascular variables, this paper proposes for the first time to use nonlinear autoregressive models with extra inputs (ARX) for BP estimation. The models were first trained by the baseline data of all 25 subjects to determine the model structure and then trained by individual data to obtain the personalized model parameters. To assess the effects of the dynamic and nonlinear factors, the data during water drinking and the first 5 minutes of recovery after drinking were used to validate the four models: linear regression, linear ARX, nonlinear regression and nonlinear ARX. The reference BP, which were measured by Finometer, were increased by 36.7±10.5 mmHg for SBP and 28.4 ±7.7 mmHg for DBP. This BP changes were best modelled by the nonlinear ARX, with Mean ± SD differences of 5.6 ± 8.8 mmHg for SBP and 3.8 ±5.8 mmHg for DBP. The study also showed that nonlinear factor significantly reduced the root mean square error (RSME) by about 50%, i.e., from 20.4 to 10.7 mmHg for SBP and 13.3 to 7.3 mmHg for DBP during drinking. While the effects of dynamic factors were not as significant as nonlinear factors, especially after introducing nonlinear factors.

17.
Medicine (Baltimore) ; 99(40): e22399, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-33019414

RESUMO

BACKGROUND: Essential hypertension remains an enormous public health concern, imposing a major burden of morbidity and mortality worldwide. Relevant studies showed that acupuncture therapy might be effective in treating essential hypertension. However, there is no consistent conclusion so far. The aim of this study was to assess the efficacy and safety of acupuncture therapy for patients with essential hypertension. METHODS: We searched the PubMed, Embase, the Cochrane Library, Web of Science, the Chinese National Knowledge Infrastructure (CNKI), and the Wan-fang databases from inception through November 29, 2019. Randomized controlled trials investigating acupuncture therapy for hypertension were included. We will use Endnote software X8 for studies selection, Review Manager software 5.3 for the data analysis. RESULTS: We will synthesize current studies to evaluate the safeties and effectiveness of acupuncture for essential hypertension. CONCLUSIONS: Our study will provide the evidence of acupuncture therapy for essential hypertension.

18.
World J Microbiol Biotechnol ; 36(11): 165, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33000364

RESUMO

YmdB, which can regulate biofilm formation independently, has been reported to exist in Bacillus subtilis. The B. cereus 0-9 genome also encodes a YmdB-like protein, which has measureable phosphodiesterase activity, and 72.35% sequence identity to YmdB protein of B. subtilis 168. In this work, we studied the function of YmdB protein and its encoding gene, ymdB, in B. cereus 0-9. Our results indicated that YmdB protein is critical for the biofilm formation of B. cereus 0-9. In ΔymdB mutant, the transcriptional levels of sinR and hag were up-regulated, and those of genes closely related to biofilm formation, such as sipW, tasA and calY, were down-regulated. Deletion of ymdB gene stimulates the swarming motility of B. cereus 0-9, and enhances it to travel outward, but reduces its ability to form complex spatial structures on the solid surface of MSgg plates. Hence, it is considered that YmdB plays a key role in biofilm formation, and this effect is likely achieved through the function of repressor SinR in B. cereus 0-9. Furthermore, by comparing the amino acid sequences of YmdB by Basic Local Alignment Search Tool (BLAST) in Genebank, we found that YmdB homologues are present in a variety of bacteria (Including Gram-negative bacteria) except B. subtilis and B. cereus. All these bacteria come at different evolutionary distances and belong to different genera. Therefore, we believe that YmdB exists in many types of bacteria and plays an important role in the stress-resistance of bacteria to adapt to the environment. These results can help us to further understand the biocontrol characteristics of B. cereus 0-9.

19.
Biosens Bioelectron ; 170: 112667, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-33035902

RESUMO

Electrochemical immunoassays are often used in the detection of biomarkers, and their sensitivity depends on the nature of the substrate and the catalytic activity of the signal amplification platform. In this work, a novel sandwich-type signal amplification strategy with a "gold-plated" organometallic frame (Au/IRMOF-3) as the substrate and the sea cucumber-like Pd@PtRh trimetallic nanomaterial (Pd@PtRh SNRs) as label was fabricated. For the substrate, gold nanoparticles (Au NPs) are stably connected to the free amino groups on the surface of organometallic frame (IRMOF-3), which not only prevent the agglomeration of Au NPs, but also greatly enhance the conductivity of the nanocomposites. The synergy between the two nanomaterials further shows a stronger affinity for the fixation of capture antibodies (Ab1). For the label, the effective high catalytic activity comes from the Pd@PtRh SNRs with a sea cucumber-like morphology. The nano-scale spherical PtRh crystals epitaxially grown on smooth Pd nanorods (Pd NRs) have more catalytically active sites because of the abundant edge and corner atoms, resulting in high catalytic activity and durability towards H2O2 reduction. Choosing calcitonin (PCT) as the target, differential pulse voltammetry (DPV) and amperometric i-t dual-mode detection was used to demonstrate the feasibility of the immunosensor. The results confirmed that the immunosensor exhibits excellent analytical capabilities and is satisfied in the analysis of human serum samples. Therefore, this strategy has great potential in the clinical application of electrochemical immunosensors.

20.
J Healthc Eng ; 2020: 7289648, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32952989

RESUMO

Neck injury is one of the most frequent spine injuries due to the complex structure of the cervical spine. The high incidence of neck injuries in collision accidents can bring a heavy economic burden to the society. Therefore, knowing the potential mechanisms of cervical spine injury and dysfunction is significant for improving its prevention and treatment. The research on cervical spine dynamics mainly concerns the fields of automobile safety, aeronautics, and astronautics. Numerical simulation methods are beneficial to better understand the stresses and strains developed in soft tissues with investigators and have been roundly used in cervical biomechanics. In this article, the simulation methods for the development and application of cervical spine dynamic problems in the recent years have been reviewed. The study focused mainly on multibody and finite element models. The structure, material properties, and application fields, especially the whiplash injury, were analyzed in detail. It has been shown that simulation methods have made remarkable progress in the research of cervical dynamic injury mechanisms, and some suggestions on the research of cervical dynamics in the future have been proposed.

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