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1.
Anal Chim Acta ; 1118: 1-8, 2020 Jun 29.
Article in English | MEDLINE | ID: mdl-32418599

ABSTRACT

In this paper a photoelectrochemical (PEC) aptasensor based on specific recognition with conformational changed after the target Cd(II) identification was fabricated. A ZnO and reduced graphene oxide (ZnO-rGO) nanocomposite with enhanced PEC activity was designed as photoactive material. After the further incorporation of gold nanoparticles (AuNPs) with ZnO-rGO nanocomposite, the enhanced photocurrent signal could be detected owing to the localized surface plasmon resonance and good conductivity of AuNPs. In addition, AuNPs were used as anchors for immobilization of -SH modified aptamer S1. After that aptamer S2 was paired with S1 sequence to form complementary double stranded DNA (dsDNA) on the electrode surface. Methylene blue (MB) was acted as sensitizer and assembled in dsDNA structure to amplify photocurrent response. When Cd(II) was bound to the aptamer presented on the sensing interface, S2 specifically recognized and captured Cd(II), which resulted in the unwinding of dsDNA structure and the separation of MB molecules from the electrode surface with photocurrent response decreased. The photocurrent was detected by a double-working-electrode system, which used the modified electrode as the first working electrode and glassy carbon electrode (GCE) as the second working electrode. Dopamine (DA) was added to the electrolyte and acted as the electron donor, which could be oxidized on the modified electrode and reduced on the GCE to form a cyclic reaction, leading to the enhanced photocurrent response with improved photocurrent stability. This MB sensitized PEC aptasensor exhibited a high sensitivity with a detection limit of 1.8 × 10-12 mol/L (3σ). Thus, a highly sensitive aptasensor with double-working-electrode detection method for Cd(II) determination were established and further applied to the water samples analysis.


Subject(s)
Aptamers, Nucleotide/chemistry , Cadmium/analysis , Electrochemical Techniques , Graphite/chemistry , Methylene Blue/chemistry , Zinc Oxide/chemistry , Biosensing Techniques , Oxidation-Reduction , Particle Size , Photochemical Processes , Surface Properties
2.
Mikrochim Acta ; 186(12): 826, 2019 11 21.
Article in English | MEDLINE | ID: mdl-31754803

ABSTRACT

A photoelectrochemical (PEC) aptasensor for Pb(II) detection is described. A nanocomposite consisting of CdS (2.5 µm) and TiO2 nanoparticles (10 nm) was used as a photoactive material, and gold nanochains (Au NCs) as the support for immobilization of the Pb(II)-binding aptamer. The quercetin-copper(II) complex was further employed as the intercalator for the improvement of the photoactivity by embedding it into dsDNA. In the presence of Pb(II), a Pb(II)-stabilized G-quadruplex was formed between Pb(II) and DNA S1. This is accompanied by unwinding of the dsDNA and the release of the quercetin-copper(II) complex from the surface of the sensor. This results in a decrease of the photocurrent that drops linearly from 5.0 × 10-12 to 1.0 × 10-8 mol·L-1 Pb(II) concentration range with a detection limit of 1.6 × 10-12 mol·L-1. The method was applied to the determination of Pb(II) in various samples and gave satisfactory results. Graphical abstractA photoelectrochemical aptasensor was fabricated for the detection of Pb(II) based on CdS-TiO2 nanocomposite modified indium tin oxide (ITO) electrode. Gold nanochains (AuNCs) were used as anchor to immobilize the aptamers S1 and S2 that form a double helix structure by DNA hybridization. After embedding of quercetin-copper(II) complex as intercalator and electron donor, the concentrations of Pb(II) were determined by the changes of photocurrents.


Subject(s)
Aptamers, Nucleotide/chemistry , Coordination Complexes/chemistry , DNA/chemistry , Intercalating Agents/chemistry , Lead/analysis , Metal Nanoparticles/chemistry , Biosensing Techniques , Cadmium Compounds/chemistry , Copper/chemistry , Electric Conductivity , Electrochemical Techniques , Electrodes , G-Quadruplexes , Gold/chemistry , Limit of Detection , Nucleic Acid Hybridization , Photochemical Processes , Quercetin/chemistry , Sulfides/chemistry , Surface Properties , Titanium/chemistry
3.
Zhongguo Zhen Jiu ; 35(2): 114-8, 2015 Feb.
Article in Chinese | MEDLINE | ID: mdl-25854013

ABSTRACT

OBJECTIVE: To explore the best therapy for infertility caused by polycystic ovary syndrome (PCOS). METHODS: One hundred and twenty patients were randomized into three groups, a clomi-phene group (group A), an acupuncture-moxibustion + Chinese medicine group (group B) and a clomiphene + acupuncture-moxibustion+ Chinese medicine group (group C), 40 cases in each one. In the group A, since the 5th day of menstruation, clomiphene was prescribed for oral administration. In the group B, on the 5th day of menstruation, warm needling therapy was applied at Zhongji (CV 3), Guanyuan (CV 4), Guilai (ST 29), etc. Additionally, the Chinese herbal medication for tonifying the kidney and activating blood circulation was provided. In the group C, the therapy as the group B was combined on the basis of the treatment as the group A. The treatment lasted continuously for 3 menstrual cycles. The endometrial thickness, endometrial type and cervical mucus score on human chorionic gon adotropin (HCG) day, and ovulatory cycle rate, clinical pregnancy rate and abortion rate after treatment were observed in the patients of the three groups. RESULTS: 1) HCG day cervical mucus score, endometrial thickness and endometrial morphology (A type rate): the results in the group C were better than those in the group A (all P<0.01); the results in the group B were better than those in the group A (all P<0.05). The difference in the endometrial thickness was not significant in comparison between the group C and the group B (P>0.05). The cervical mucus score and endometrial morphology (A type rate) in the group C were better than those in the group B (both P<0.05). 2) The ovulatory cycle rates in the group A and group (C were higher than that in the group B (both P<0.05), the pregnancy rate in the group C was higher than that in the other groups (both P<0.05), and the early abortion rate in the group C was lower than that in the group A and group B (both P<0.01). 3) Follicle diameter from 18 mm to 20 mm and endometrial thickness: the differences were not significant between the normal pregnancy patients and the early abortion patients (both P>0.05). The endometrial morphology A type rate in the normal pregnancy patients was higher than that in the early abortion patients (P<0.05). CONCLUSION: The combined therapy of acupuncture, herbal medicine and clomiphene improves the pregnancy rate and reduces early abortion rate by effectively improving HCG day cervical mucus, endometrial thickness and morphology. The efficacy is apparently superior to the simple medication with clomiphene and the combined application of acupuncture and herbal medicine.


Subject(s)
Acupuncture Therapy , Clomiphene/administration & dosage , Fertility Agents, Female/administration & dosage , Infertility, Female/therapy , Administration, Oral , Adult , Chorionic Gonadotropin/metabolism , Combined Modality Therapy , Female , Humans , Infertility, Female/drug therapy , Infertility, Female/etiology , Infertility, Female/metabolism , Moxibustion , Polycystic Ovary Syndrome , Pregnancy , Pregnancy Rate , Young Adult
4.
Zhongguo Zhen Jiu ; 34(2): 130-4, 2014 Feb.
Article in Chinese | MEDLINE | ID: mdl-24796046

ABSTRACT

OBJECTIVE: To explore the effects of warm needling combined with Zhangmo decoction (see text) on endometrial receptivity in patients with clomiphene (CC)-induced ovulation. METHODS: One hundred and sixty cases were randomly divided into a CC group (group A), a CC+ progynova group (group B), a CC+ Zhangmo decoction group (group C) and a CC+ Zhangmo decoction + warm needling group (group D), 40 cases in each one. In the Group A, CC alone was applied. In the group B, progynova was jointly used on the 8th day of menstrual cycle. In the Group C, Zhangmo decoction was jointly used on the 5th day of menstrual cycle. In the group D, based on treatment of the Zhangmo decoction, warm needling was applied at Guanyuan (CV 4), Zhongji (CV 3) and Zigong (EX-CA 1) etc. The endometrial thickness and type, pulsatility index (PI), resistance index (RI), ratio of S/D on day of human chorionic gonadotropin (HCG) and pregnancy rate were observed in fou groups. RESULTS: The PI, RI and S/D in the group C and D were obviously lower than those in group A and B (all P < 0.01). The endometrial thickness was (7.7 +/- 1.49) mm in group B, (8.2 +/- 1.54) mm in group C and (8.9 +/- 1.51) mm in group D, which were significantly different from (6.4 5 +/- 1.26) mm in the group A (all P < 0.01) also there was a significant difference between group C and D (P < 0.05). The rate of endometrial type A was 65.0% in the group D, which was significantly higer than 27.5% in the group A, 32.5% in the group B and 35.0% in the group C (all P < 0.01). The pregnancy rate was 30.0% in the group D, which was obviously higher than 12.5% in the group A, 15.0% in the group B and 17.5% in the group C (P < 0.05). The endometrial thickness and rate of endometrial type A in the pregnant were obviously higher than those in the non-pregnant (both P < 0.01) while PI, RI and S/D was lower than those in the non-pregnant (P < 0.01, P < 0.05). CONCLUSION: Warm needing combined with Zhangmo decoction could improve endometrial thickness, morphology and uterine spiral artery to improve pregnancy rate, which has superior effect to clomiphene, clomiphene combined with progynova and clomiphene combined with Zhangmo decoction.


Subject(s)
Drugs, Chinese Herbal/administration & dosage , Infertility, Female/therapy , Chorionic Gonadotropin/metabolism , Clomiphene/administration & dosage , Combined Modality Therapy , Embryo Transfer , Female , Fertilization in Vitro , Humans , Infertility, Female/drug therapy , Infertility, Female/metabolism , Infertility, Female/physiopathology , Ovulation Induction , Pregnancy
5.
Mol Immunol ; 57(2): 93-9, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24084097

ABSTRACT

Accumulative evidence demonstrates that multiple sclerosis (MS) is caused by activation of myelin Ag-reactive CD4+ T cells. Therefore, the CD4+ T cells specific for myelin Ag may be the important therapeutical target of MS. The novel coinhibitory receptor B and T lymphocyte attenuator (BTLA) may have a regulatory role in maintaining peripheral tolerance, however, its role in MS is still unknown. In this study, a novel nanoparticle containing MOG peptide with BTLA was designed and transduced into dendritic cells (DCs), and MOG peptide-induced EAE mice were administrated with the genetically modified DCs in vivo. The results demonstrated that modified DCs significantly enhanced the proportion of Foxp3+ CD4+ regulatory T cells, increased IL-10 and TGF-ß cytokine secretion, while decreased IL-2 and IFN-γ cytokine secretion. Furthermore, modified DCs supressed the CD4+ T cell response to MOG, cell infiltration into spinal cord, and the severity of EAE. In contrast, immune response to irrelevant exogenous Ag was not impaired by treatment with modified DCs. These findings suggested that DCs transduced with nanoparticle could induce specific CD4+ T-cells tolerance, which provided a promising therapeutic means to negatively manipulate immune response for autoimmune diseases without inhibition of the immune response to irrelevant Ag.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Encephalomyelitis, Autoimmune, Experimental/prevention & control , Multiple Sclerosis/prevention & control , Myelin-Oligodendrocyte Glycoprotein/therapeutic use , Nanoparticles/therapeutic use , Receptors, Immunologic/therapeutic use , Animals , Dendritic Cells/cytology , Dendritic Cells/immunology , Encephalomyelitis, Autoimmune, Experimental/immunology , Female , Forkhead Transcription Factors/metabolism , Gene Transfer Techniques , Immune Tolerance/immunology , Interferon-gamma/biosynthesis , Interleukin-10/biosynthesis , Interleukin-2/biosynthesis , Mice , Mice, Inbred C57BL , Multiple Sclerosis/immunology , Myelin Sheath/immunology , Transforming Growth Factor beta/biosynthesis
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