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1.
ACS Appl Mater Interfaces ; 11(45): 42856-42864, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31633324

RESUMO

Poly(acrylic acid) (PAA) hydrogels with a multi-bond network composed of sparse chemical cross-links and carboxyl-Fe3+ coordination are prepared through a controllable permeation strategy utilizing ferric citrate (FeCA). The existing strategies that directly soak PAA hydrogels in Fe3+ solutions usually induce an inhomogeneous network with densely cross-linked shells and uncertain water content of the hydrogels, which brings about ambiguity when investigating strengthening mechanisms because water content significantly affects the mechanical properties of hydrogels. Herein, the controllable permeation of Fe3+ into PAA networks based on the competition between citric acid (CA)-Fe3+ chelation and PAA-Fe3+ coordination guarantees sustained release of Fe3+, facilitating homogeneous distribution of ionic cross-links and a certain water content. The obtained hydrogels exhibit excellent and balanced mechanical properties (high tensile strength of 3.28 to 6.95 MPa with large elongations at break of 1400 to 780% when water content decreases from 80 to 50 wt %). The real robust tensile strength of this hydrogel originates from the effective energy dissipation of the homogeneous PAA-Fe3+ cross-links, and the high water content ensures a large elongation at break. Furthermore, the hydrogel also has pH-responsive and shape-memory properties.

2.
Sci Rep ; 9(1): 14013, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31570733

RESUMO

Few pieces of evidence have been published on the use of Apatinib Mesylate (AM) against EGFR-TKI resistance in lung adenocarcinoma (LA) patients. Here, we investigate the clinical efficacy and safety of AM in the treatment of advanced progressed epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKI) resistant LA patients. We conducted a double-blind, randomized controlled trial in 68 patients admitted to 18 hospitals of Anhui province in China. The efficacy and safety of AM treatment were evaluated in terms of progression-free survival (PFS), objective response rate (ORR), and disease control rate (DCR), as well as related adverse events (AE). A literature knowledge database analysis and a pathway model reconstruction were performed to decipher the relevant mechanism may be involved. Our results showed that, compared to the control group, AM presented improved efficacy in PFS (P = 0.033), ORR (P < 0.001), and DCR (P < 0.001). No significant difference was observed between case and control group in terms of AE, and no drug-related death occurred. Pathway analysis supports that Apatinib can be repurposed for the treatment of LA. Our results suggested that AM could be a potential option for advanced progressed LA patients to combat EGFR-TKI resistance.

3.
J Am Chem Soc ; 141(44): 17493-17497, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31609609

RESUMO

The affinity of aptamers relies on their adaptive folding, but the excessive flexibility of the aptamer backbone usually hampers the folding process. Thus, there is an urgent need to engineer aptamers with more stable and defined structures. Herein, we report a postselection strategy for stabilizing aptamer structures, by fixing both termini of the aptamer with a length-optimized triple helix structure. An anti-lysozyme aptamer was engineered in this way, and its affinity was enhanced by almost 10-fold. An electrochemical aptasensor was designed based on this engineered aptamer, assisted by a DNA tetrahedron as a spacer to orient the aptamer. The aptasensor achieved a 180-fold lower limit of detection than that achieved by the aptasensor without termini-fixed aptamer and exhibited high sensitivity and selectivity toward lysozyme in real red wine samples. This work sheds light on engineering aptamers to achieve enhanced affinity and on the application of aptasensors in complex matrices.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31650689

RESUMO

Expanding the number of nucleotides in DNA increases the information density of functional DNA molecules, creating nanoassemblies that cannot be invaded by natural DNA/RNA in complex biological systems. Here, we show how six-letter GACTZP DNA contributes this property in two parts of a nanoassembly: 1) in an aptamer evolved from a six-letter DNA library to selectively bind liver cancer cells; and 2) in a six-letter self-assembling GACTZP nanotrain that carries the drug doxorubicin. The aptamer-nanotrain assembly, charged with doxorubicin, selectively kills liver cancer cells in culture, as the selectivity of the aptamer binding directs doxorubicin into the aptamer-targeted cells. The assembly does not kill untransformed cells that the aptamer does not bind. This architecture, built with an expanded genetic alphabet, is reminiscent of antibodies conjugated to drugs, which presumably act by this mechanism as well, but with the antibody replaced by an aptamer.

5.
Sci Rep ; 9(1): 12058, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31427711

RESUMO

Clubroot disease is one of the major diseases affecting Brassica crops, especially Chinese cabbage (Brassica rapa L. ssp. pekinensis), which is known to be highly susceptible to the disease. In this study, the obligate biotrophic protist Plasmodiophora brassicae Woronin was used to infect the roots of Chinese cabbage seedlings. The disease symptoms were noticeable at 28 and 35 days after inoculation (DAI) in the susceptible (CM) line. Using isobaric tags for relative and absolute quantitation (iTRAQ) analysis, a total of 5,003 proteins of differential abundance were identified in the resistant/susceptible lines, which could be quantitated by dipeptide or polypeptide segments. Gene ontology (GO) analysis indicated that the differentially expressed proteins (DEPs) between the susceptible (CM) and resistant (CCR) lines were associated with the glutathione transferase activity pathway, which could catalyze the combination of glutathione and other electrophilic compounds to protect plants from disease. In addition, the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that the DEPs may be significantly enriched cytokinin signaling or arginine biosynthesis pathways, both of which are responses to stimuli and are plant defense reactions. The cytokinins may facilitate cell division in the shoot, resulting in the hypertrophy and formation of galls and the presentation of typical clubroot symptoms. In this study, the proteomic results provide a new perspective for creating germplasm resistance to P. brassicae, as well as a genetic basis for breeding to improve Chinese cabbage.

6.
BMC Genomics ; 20(1): 396, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31113376

RESUMO

BACKGROUND: Phenotypic plasticity is a common and highly adaptive phenomenon where the same genotype produces different phenotypes in response to environmental cues. Sogatella furcifera, a migratory pest of rice exhibits wing dimorphism, is a model insect for studying phenotypic plasticity of wing size. The Insullin-PI3K-Akt-FOXO signaling pathway plays a crucial role in the manipulation of wing size in the migratory insects. However, the regulatory mechanism via the pathway involved in wing dimorphism are still unexplored. RESULTS: Accompanied by special alternative splicing, genes involved in muscle contraction and energy metabolism were highly expressed in the wing hinges of macropters, demonstrating their adaptation for energy-demanding long-distance flights. Based on FOXO ChIP-Seq analysis, a total of 1259 putative target genes were observed in the wing hinges, including wing morph development, flight muscle and energy metabolism genes. An integrated gene interaction network was built by combining four heterogeneous datasets, and the IIS-PI3K-Akt-FOXO pathway was clustered in a divided functional module. In total, 45 genes in the module directly interacting with the IIS-PI3K-Akt-FOXO pathway showed differential expression levels between the two wing hinges, thus are regarded as potential Insulin pathway mediated wing dimorphism related genes (IWDRGs). Of the 45 IWDRGs, 5 were selected for verification by gene knockdown experiments, and played significant roles in the insect wing size regulation. CONCLUSIONS: We provided valuable insights on the genetic basis of wing dimorphism, and also demonstrated that network analysis is a powerful approach to identify new genes regulating wing dimorphic development via insulin signaling pathway in the migratory insect.


Assuntos
Genes de Insetos , Hemípteros/genética , Insulina/fisiologia , Asas de Animais/metabolismo , Processamento Alternativo , Animais , Ácidos Graxos/metabolismo , Feminino , Fatores de Transcrição Forkhead/metabolismo , Expressão Gênica , Redes Reguladoras de Genes , Hemípteros/anatomia & histologia , Hemípteros/metabolismo , Proteínas de Insetos/metabolismo , Proteínas Musculares/genética , Fenótipo , Transdução de Sinais , Asas de Animais/anatomia & histologia
7.
Angew Chem Int Ed Engl ; 58(6): 1621-1625, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30556364

RESUMO

Regulation of protein activity is essential for revealing the molecular mechanisms of biological processes. DNA and RNA achieve many uniquely efficient functions, such as genetic expression and regulation. The chemical capability to synthesize artificial nucleotides can expand the chemical space of nucleic acid libraries and further increase the functional diversity of nucleic acids. Herein, a versatile method has been developed for modular expansion of the chemical space of nucleic acid libraries, thus enabling the generation of aptamers able to regulate protein activity. Specifically, an aptamer that targets integrin alpha3 was identified and this aptamer can inhibit cell adhesion and migration. Overall, this chemical-design-assisted in vitro selection approach enables the generation of functional nucleic acids for elucidating the molecular basis of biological activities and uncovering a novel basis for the rational design of new protein-inhibitor pharmaceuticals.

8.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 30(11): 1029-1035, 2018 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-30541640

RESUMO

OBJECTIVE: To survey the distribution pattern and subject domain knowledge of the literatures about ventilator-associated pneumonia (VAP). METHODS: Literatures about VAP published until December 2017 were identified in SinoMed database for statistics and analysis. The information of author, organization and province was extracted by BICOMS software for generating co-occurrence matrix, at the same time, the topic words were cluster analyzed by Gcluto software to generate topical visual surface maps and visualization matrices, and the current research hotspots were analyzed. NetDraw from Ucinet 6.0 software was used to arrange the relationship among topic words according to the centrality, and the social network diagrams of authors, authors' provinces and institutions were draw to analyze the current status of VAP research cooperation. RESULTS: 4 851 VAP-related literatures were retrieved preliminarily, and 43 were excluded from abstracts, news reports, information and missing literatures. Finally, a total of 4 808 articles were enrolled in the visual analysis. From 2001 to 2004, the number of VAP-related literatures published was less than 10. Since 2009, the number of VAP documents had increased steadily, from 2010 to 2017, the peak period of publications reached 91.7% (4 411/4 808). According to the analysis of the amount of publications, the top three of 34 provincial administrative regions that published VAP-related literature in China were Guangdong Province (n = 628), Jiangsu Province (n = 478) and Zhejiang Province (n = 404), the number of hospitals issued by the First Affiliated Hospital of Chongqing Medical University was the largest (n = 20); there was only one journal with more than 100 articles, and there were 154 journals with only one article, accounting for 34.8% of the total number of journals. A total of 9 921 authors participated in the VAP-related literature writing, the number of high-yielding authors was not large, and the institution could not establish an effective social network diagram, suggesting that communication and cooperation should be strengthened in hospitals and outside hospitals. The results of the topic words social network analysis showed that the VAP research field was centered around the core of "mechanical ventilation", "intensive care unit (ICU)", "risk factor analysis", "nursing", "etiological analysis", "preventive measures" and "pathogens". The current research hotspots were at the edge of the network map, such as "drug sensitivity analysis", "Acinetobacter baumannii", "bronohoalveolar lavage (BAL)" and "acute exacerbation of chronic obstructive pulmonary disease (AECOPD)". By clustering 80 high-frequency topic words, at present, VAP research hotspots were mainly focus on five topics: obstructive pulmonary disease, especially in acute exacerbation, was prone to VAP; concerned about newborns and children's VAP; types, drug resistance and selection of antimicrobial agents for VAP pathogens in ICU; clinical efficacy and prognosis of VAP through preventive measures, pulmonary supportive care and comprehensive care interventions; oral care and airway management during mechanical ventilation was also the key aspect of the treatment of VAP. CONCLUSIONS: In recent years, the academics had attached great importance to the study of VAP, the number of publications had reached a historical peak, and the research direction was diverse. However, it was necessary to strengthen cooperation among research institutes, collect and count epidemiological data, improve and expand the research quality and scale of clinical diagnosis, nurse, prevention, pathogen distribution and drug resistance analysis.


Assuntos
Pesquisa Biomédica/estatística & dados numéricos , Pneumonia Associada à Ventilação Mecânica , China , Bases de Dados Factuais , Humanos
9.
Hippocampus ; 2018 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-30471164

RESUMO

OBJECTIVES: To investigate remodeling of hippocampal cholinergic inputs after noise exposure and determine the relevance of these changes to tinnitus. METHODS: To assess the effects of noise exposure on the hippocampus, guinea pigs were exposed to unilateral noise for two hours and 2 weeks later, immunohistochemistry was performed on hippocampal sections to examine vesicular acetylcholine transporter (VAChT) expression. To evaluate whether the changes in VAChT were relevant to tinnitus, another group of animals was exposed to the same noise band twice to induce tinnitus, which was assessed using gap-prepulse Inhibition of the acoustic startle (GPIAS) 12 weeks after the first noise exposure, followed by immunohistochemistry. RESULTS: Acoustic Brainstem Response (ABR) thresholds were elevated immediately after noise exposure for all experimental animals but returned to baseline levels several days after noise exposure. ABR wave I amplitude-intensity functions did not show any changes after 2 or 12 weeks of recovery compared to baseline levels. In animals assessed two-weeks following noise-exposure, hippocampal VAChT puncta density decreased on both sides of the brain by 20%-60% in exposed animals. By 12 weeks following the initial noise exposure, changes in VAChT puncta density largely recovered to baseline levels in exposed animals that did not develop tinnitus, but remained diminished in animals that developed tinnitus. These tinnitus-specific changes were particularly prominent in hippocampal synapse-rich layers of the dentate gyrus and areas CA3 and CA1, and VAChT density in these regions negatively correlated with tinnitus severity. CONCLUSIONS: The robust changes in VAChT labeling in the hippocampus two weeks after noise exposure suggest involvement of this circuitry in auditory processing. After chronic tinnitus induction, tinnitus-specific changes occurred in synapse-rich layers of the hippocampus, suggesting that synaptic processing in the hippocampus may play an important role in the pathophysiology of tinnitus. This article is protected by copyright. All rights reserved.

10.
Sci China Chem ; 61(4): 497-504, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30271427

RESUMO

Drug administration customized to individual cells could intrinsically address cancer heterogeneity and provide a safe and effective method for delivering personalized treatment. To accomplish this, we developed a smart nanodrug delivery system characterized by cancer cell-targeted drug delivery and intracellular biomarker-responsive drug activation. This system was composed of a long-nicked DNA duplex formed by tandem hybridization of two extended antisense oligonucleotides whose ends were separately blocked with a cancer cell-specific aptamer, AS1411, and a replaceable anti-biomarker probe (ABP). We demonstrated that this DNA nanodrug was directed to cancer cells with the guidance power of AS1411 and then activated by the presence of a given intracellular biomarker. By using such a belt-and-braces strategy, this DNA nanodrug system could safely and efficiently accelerate apoptosis of target cancer cells. Moreover, since the expression level of biomarkers tends to indicate the specific physiological state of individual cells, biomarker-responsive activation of the nanodrug is expected to enable customized drug administration at the cellular level.

11.
Plant Cell Environ ; 2018 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-30251262

RESUMO

Herbivore damage by chewing insects activates jasmonate (JA) signalling that can elicit systemic defense responses in rice. Few details are known, however, concerning the mechanism, whereby JA signalling modulates nutrient status in rice in response to herbivory. (15 NH4 )2 SO4 labelling experiments, proteomic surveys, and RT-qPCR analyses were used to identify the roles of JA signalling in nitrogen (N) uptake and allocation in rice plants. Exogenous applications of methyl jasmonate (MeJA) to rice seedlings led to significantly reduced N uptake in roots and reduced translocation of recently-absorbed 15 N from roots to leaves, likely occurring as a result of down-regulation of glutamine synthetase cytosolic isozyme 1-2 and ferredoxin-nitrite reductase. Shoot MeJA treatment resulted in a remobilization of endogenous unlabelled 14 N from leaves to roots, and root MeJA treatment also increased 14 N accumulation in roots but did not affect 14 N accumulation in leaves of rice. Additionally, proteomic and RT-qPCR experiments showed that JA-mediated plastid disassembly and dehydrogenases GDH2 up-regulation contribute to N release in leaves to support production of defensive proteins/compounds under N-limited condition. Collectively, our results indicate that JA signalling mediates large-scale systemic changes in N uptake and allocation in rice plants.

12.
Anal Chem ; 90(17): 10487-10493, 2018 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-30039967

RESUMO

A comprehensive nonlinear regression model for dissociation equilibria of cell-specific aptamers is proposed by considering the effect of receptor expression level. Benefiting from the global regression of simultaneous equations, the fitted parameters reach a very significant level, indicating the statistical validity of this updated model. According to the fitting results, we found that dissociation constants fitted using the previous model are obviously larger than the updated values, which can be explained by the effect of receptor number on curve fitting. In addition, equivalent receptor density can be estimated using the updated model, which may lead to some new judgments about reported results of cell-SELEX.

13.
Microb Cell Fact ; 17(1): 116, 2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30037328

RESUMO

BACKGROUND: Pine wilt disease, caused by the pinewood nematode Bursaphelenchus xylophilus (PWN), is an important destructive disease of pine forests worldwide. In addition to behaving as a plant-parasitic nematode that feeds on epithelial cells of pines, this pest relies on fungal associates for completing its life cycle inside pine trees. Manipulating microbial symbionts to block pest transmission has exhibited an exciting prospect in recent years; however, transforming the fungal mutualists to toxin delivery agents for suppressing PWN growth has received little attention. RESULTS: In the present study, a nematicidal gene cry5Ba3, originally from a soil Bacillus thuringiensis (Bt) strain, was codon-preferred as cry5Ba3Φ and integrated into the genome of a fungus eaten by PWN, Botrytis cinerea, using Agrobacterium tumefaciens-mediated transformation. Supplementing wild-type B. cinerea extract with that from the cry5Ba3Φ transformant significantly suppressed PWN growth; moreover, the nematodes lost fitness significantly when feeding on the mycelia of the cry5Ba3Φ transformant. N-terminal deletion of Cry5Ba3Φ protein weakened the nematicidal activity more dramatically than did the C-terminal deletion, indicating that domain I (endotoxin-N) plays a more important role in its nematicidal function than domain III (endotoxin-C), which is similar to certain insecticidal Cry proteins. CONCLUSIONS: Transformation of Bt nematicidal cry genes in fungi can alter the fungivorous performance of B. xylophilus and reduce nematode fitness. This finding provides a new prospect of developing strategies for breaking the life cycle of this pest in pines and controlling pine wilt disease.


Assuntos
Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/metabolismo , Botrytis/metabolismo , Nematoides/metabolismo , Nematoides/microbiologia , Animais , Bacillus thuringiensis/genética , Proteínas de Bactérias/genética , Botrytis/genética , Nematoides/genética , Pinus/parasitologia
14.
Nanoscale ; 10(23): 10986-10990, 2018 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-29856447

RESUMO

We designed an aptamer-based multifunctional ligand which, upon conjugation to the surface of upconversion nanoparticles (UCNPs), could realize phase transfer, covalent photosensitizer (PS) loading, and cancer cell targeting in one simple step. The as-built PDT nanodrug is selectively internalized into cancer cells and it exhibits highly efficient and selective cytotoxicity.

15.
Chem Sci ; 9(11): 3050-3055, 2018 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-29732089

RESUMO

We herein describe a simple and versatile approach to use conventional nicking endonuclease (NEase) for programmable sequence-specific cleavage of DNA, termed aligner-mediated cleavage (AMC), and its application to DNA isothermal exponential amplification (AMC-based strand displacement amplification, AMC-SDA). AMC uses a hairpin-shaped DNA aligner (DA) that contains a recognition site in its stem and two side arms complementary to target DNA. Thus, it enables the loading of an NEase on DA's stem, localization to a specific locus through hybridization of the side arms with target DNA, and cleavage thereof. By using just one NEase, it is easy to make a break at any specific locus and tune the cleavage site to the single-nucleotide scale. This capability also endows the proposed AMC-SDA with excellent universality, since the cleavage of target DNA, followed by a polymerase-catalyzed extension along a particular primer as a key step for initiating SDA, no longer relies on any special sequence. Moreover, this manner of initiation facilitates the adoption of 3'-terminated primers, thus making AMC-SDA highly sensitive and highly specific, as well as simple primer design.

16.
J Med Virol ; 90(9): 1541-1548, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29704442

RESUMO

To identify factors for predicting residual or recurrent cervical intraepithelial neoplasia (CIN) after cervical conization with negative margins. A total of 172 patients with histologically verified high-grade squamous intraepithelial lesions who underwent conization with negative margins were recruited at the General Hospital of Tianjin Medical University from December 2006 to January 2016. Follow-up comprised clinical examination, a liquid-based cytology test, a human papillomavirus (HPV) DNA genotyping test, colposcopy assessment, and if indicated, colposcopy-directed punch biopsy. The Kaplan-Meier method was used to analyze the median recurrent time, whereas log-rank tests and Cox regression models were used to determine the predictors of residual/recurrent CIN. Fourteen residual/recurrent cases (8.1%) were identified in 172 patients. In univariate analysis, cytologic abnormalities on follow-up (P = .000), conization method (P = .017), HPV positivity at any visit (P = .000), persistent HPV infection postconization (P = .000), persistent infection with the same HPV genotype (P = .000), and HPV positivity at 18 months after conization (P = .000) were predictive factors of residual/recurrent CIN. The results of multivariate analysis further revealed that persistent HPV infection postconization (P = .035), HPV positivity at 18 months after conization (P = .017), and cytologic abnormalities on follow-up (P = .000) had an increased risk of residual/recurrent CIN. During follow-up, patients with persistent HPV infection or cytologic abnormalities were at high risk of residual/recurrent CIN and should be identified for close surveillance and monitoring. Meanwhile, patients with HPV who became negative within 18 months after treatment had a low risk of recurrence.

17.
Oncotarget ; 9(10): 9166-9176, 2018 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-29507681

RESUMO

Objective: To evaluate the diagnostic accuracy of the 2011 International Federation for Cervical Pathology and Colposcopy (IFCPC) colposcopic terminology. Methods: The clinicopathological data of 2262 patients who underwent colposcopy from September 2012 to September 2016 were reviewed. The colposcopic findings, colposcopic impression, and cervical histopathology of the patients were analyzed. Correlations between variables were evaluated using cervical histopathology as the gold standard. Results: Colposcopic diagnosis matched biopsy histopathology in 1482 patients (65.5%), and the weighted kappa strength of agreement was 0.480 (P<0.01). Colposcopic diagnoses more often underestimated (22.1%) than overestimated (12.3%) cervical pathology. There was no significant difference between the colposcopic diagnosis and cervical pathology agreement among the various grades of lesions (P=0.282). The sensitivity, specificity for detecting high-grade lesions/carcinoma was 71.6% and 98.0%, respectively. Multivariate analysis showed that major changes were independent factors in predicting high-grade lesion/carcinoma, whereas transformation zone, lesion size, and non-stained were not statistically related to high-grade lesion/carcinoma. Conclusions: The 2011 IFCPC terminology can improve the diagnostic accuracy for all lesion severities. The categorization of major changes and minor changes is appropriate. However, colposcopic diagnosis remains unsatisfactory. Poor reproducibility of type 2 transformation zone and the significance of leukoplakia require further study.

18.
Oncotarget ; 9(4): 4366-4374, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29435108

RESUMO

Mutations in the dual oxidase 2 gene (DUOX2) impair hydrogen peroxide (H2O2) production and cause dyshormonogenesis. In addition, these mutations have been implicated in autosomal recessive congenital hypothyroidism (CH) with goiter. In this study, we identified DUOX2 mutations that were causative for CH and explored the effects of these mutations on DUOX2 function. Blood samples were collected from 10 infants born with CH and goiter to unrelated parents. We extracted genomic DNA and sequenced all exons by polymerase chain reaction direct sequencing. The effects of DUOX2 mutations were characterized by H2O2 production assays and cycloheximide (CHX) chase experiments. Sequence analysis revealed one novel DUOX2 mutation and one known DUOX2 mutation in unrelated families: c.1060C>T (p.R354W) and c.3616 G>A (p.A1206T). Both mutations impaired H2O2 production. CHX chase experiments demonstrated the DUOX2 mutants had shorter half-lives and degraded more rapidly than wild-type DUOX2. Our study identified two novel DUOX2 mutations in Chinese patients with CH and goiter, which were responsible for the deficit in the organification process.

19.
Phys Chem Chem Phys ; 20(6): 4373-4385, 2018 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-29368762

RESUMO

Two kinds of bidentate Schiff base ligands derived from benzaldehyde, benzaldehyde/m-aminophenol (BAMA) type and benzaldehyde/glutamic acid (BAGL) type ligands, were synchronously synthesized and bonded on the backbone of polysulfone (PSF) through molecular design and by polymer reactions, and two functional polymers, PSF-BAMA and PSF-BAGL, were obtained. Then two series of novel luminescent Schiff base-type polymer-rare earth complexes were prepared via coordination reactions. In this work, the effects of the structures of the bonded ligands on the photoluminescence performance of the complexes were investigated in detail, and for the different photophysical properties of the prepared complexes, relevant theoretical explanations were given. The experimental results show that the bonded ligand BAMA can strongly sensitize the fluorescence emission of Eu(iii) ions, and the binary complex PSF-(BAMA)3-Eu(iii) emits strong red fluorescence under UV light. The reason for this lies in the fact that a larger conjugate π-bond system is contained in the structure of BAMA, and so the triplet state of BAMA can be matched with the resonant energy level of the Eu(iii) ion. While the bonded ligand BAGL can effectively sensitize the fluorescence emission of Tb(iii) ions, the binary complex PSF-(BAGL)3-Tb(iii) exhibits very strong green fluorescence under UV light. The reason is that a smaller conjugate π-bond system is contained in the structure of BAGL and there is a good energy level matching between the triplet state of BAGL and the resonant energy level of the Tb(iii) ion. The fluorescence intensities of the two ternary complexes, PSF-(BAMA)3-Eu(iii)-(Phen)1 (phenanthroline, Phen) and PSF-(BAGL)3-Tb(iii)-(Phen)1, are much stronger than that of the corresponding binary complex because Phen as the second ligand has two effects, the effect of synergistic coordination with the first ligand and the effect of replacing the coordinated water around the central ion, and it has been confirmed by fluorescence spectroscopy and thermogravimetric analysis.

20.
J Am Chem Soc ; 140(1): 2-5, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29256602

RESUMO

Enhanced targeted gene transduction by AAV2 vectors is achieved by linking the vector to multiple sgc8 aptamers, which are selective for cell membrane protein PTK7. Aptamer molecules are conjugated to multiple sites on a DNA dendrimer (G-sgc8), which is then linked to AAV2 via a dithiobis(succinimidyl propionate) cross-linker containing a disulfide group, which can facilitate the release of AAV2 vectors by reaction with the reduced form of intracellular glutathione. The G-sgc8-AAV2 vectors showed a 21-fold enhancement in binding affinity and an enhanced ability to protect sgc8 aptamers against nuclease degradation to cells expressing PTK7 compared to single aptamer-AAV2 conjugates. The transduction efficiency was tested by loading AAV2 with the gene for green fluorescent protein. Therefore, this modified recombinant vector is an attractive and promising tool for targeted biomedical applications.


Assuntos
Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Dissulfetos/química , Vetores Genéticos/química , Vetores Genéticos/genética , Transdução Genética/métodos , Vírus/genética , Linhagem Celular Tumoral , DNA de Neoplasias/química , Dendrímeros/síntese química , Dendrímeros/química , Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Oxirredução , Vírus/química
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