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1.
Stem Cell Res ; 61: 102768, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35421845

RESUMO

Epilepsy is a common chronic neurological disorder related to genetic factors. Base on the non-integrating episomal vector technique, a human induced pluripotent stem cell (iPSC) line, termed as LZUSHI001-A, was generated from peripheral blood mononuclear cells (PBMCs) of a 11-year-old male patient with Epilepsy, who had a heterozygous (c.2042G>A, p.R681Q) mutation in the DGKG gene. LZUSHI001-A offers a useful resource to investigate pathogenic mechanisms in epilepsy, as well as a cell-based model for drug development to treat epilepsy.


Assuntos
Epilepsia , Células-Tronco Pluripotentes Induzidas , Criança , Epilepsia/genética , Epilepsia/patologia , Heterozigoto , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucócitos Mononucleares , Masculino , Mutação/genética
2.
Mikrochim Acta ; 187(4): 234, 2020 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-32180011

RESUMO

This review (with 145 refs.) summarizes the progress that has been made in the use of zeolitic imidazolate frameworks in chemical sensing and biosensing. Zeolitic imidazolate frameworks (ZIFs) are a type of porous material with zeolite topological structure that combine the advantages of zeolite and traditional metal-organic frameworks. Owing to the structural flexibility of ZIFs, their pore sizes and surface functionalization can be reasonably designed. Following an introduction into the field of metal-organic frameworks and the zeolitic imidazolate framework (ZIF) subclass, a first large section covers the various kinds and properties of ZIFs. The next large section covers electrochemical sensors and assays (with subsections on methods for gases, electrochemiluminescence, electrochemical biomolecules). This is followed by main sections on ZIF-based colorimetric and luminescent sensors, with subsections on sensors for metal ions and anions, for gases, and for organic biomolecules. The last section covers SERS-based assays. Several tables are presented that give an overview on the wealth of methods and materials. A concluding section summarizes the current status, addresses current challenges, and gives an outlook on potential future trends. Graphical abstract In recent years, ZIFs and their composites have been widely used as probes in chemical sensing, and these probes have shown great advantages over other materials. This review describes the current progress on ZIFs toward electrochemical, luminescence, colorimetric, and SERS-based sensing applications, highlighting the different strategies for designing ZIFs and their composites and potential challenges in this field.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Imidazóis/química , Estruturas Metalorgânicas/química , Zeolitas/química , Fenômenos Ópticos
3.
ACS Appl Mater Interfaces ; 11(35): 31755-31762, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31393692

RESUMO

Nanoscale metal-organic frameworks (NMOFs) have been proved to be effective quenching platforms for fluorescent detection of DNA via fluorophore-quencher pairs. Zeolitic imidazolate framework-8 (ZIF-8) is one type of the most promising NMOFs because of its excellent biocompatibility and easy preparation. However, ZIF-8 is rarely used as platforms for fluorescence sensing of DNA because of its bad fluorescence quenching property. In this study, lanthanide ions were doped into ZIF-8 to regulate its fluorescence quenching behavior. The La3+ doped ZIF-8 (ZIF-8-La) showed the best quenching efficiency on dye-labeled DNA. The signal-to-background ratio was around 3 times higher than ZIF-8. Furthermore, a core-shell La3+-doped ZIF-8 (CS-ZIF-8-La) was designed to modify more La3+ on the surface of ZIF-8. Compared with ZIF-8-La, the CS-ZIF-8-La exhibited the same fluorescence sensing behavior toward positive-dye-labeled DNA, but showed completely contrary quenching property on the negative-dye-labeled DNA. On the basis of this phenomenon, CS-ZIF-8-La was successfully used as quenching platform for designing a ratiometric sensor for DNA and microRNA.


Assuntos
Aptâmeros de Nucleotídeos/química , DNA/análise , Lantânio/química , Estruturas Metalorgânicas/química , MicroRNAs/análise , Zeolitas/química , Fluorescência , Células HeLa , Humanos
4.
Anal Sci ; 34(12): 1379-1384, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30146543

RESUMO

A new type of fluorescent coordination polymer (NCPCd) based on disulfide carboxylate ligand was prepared by using one-pot synthesis for sensitive detection of reactive oxygen species (ROS). With the reaction between NCPCd and ROS, the morphology of the NCPCd was transformed from nanorods to hexagon particles, then broken into nano-fragments. Meanwhile, the fluorescence of NCPCd (at 421 nm) was quenched accordingly. For designing the highly sensitive probe for ROS, Rhodamine 6G (R6G) was doped in NCPCd. In the presence of ROS, the fluorescence of NCPCd moiety at 421 nm was quenched, but the R6G moiety was released from the broken nanorods and the fluorescence at 555 nm from R6G moiety was recovered. The R6G doped NCPCd (NCPCd-R) can be used as a highly sensitive and selective probe for hydrogen peroxide (H2O2) with detection limit of 12.4 nM. Moreover, the NCPCd-R was further extended to the glucose sensing combined with glucose oxidase (GOx) to oxidate glucose and generate H2O2, demonstrating the potential for practical applications.


Assuntos
Benzoatos/química , Técnicas Biossensoriais/métodos , Complexos de Coordenação/química , Peróxido de Hidrogênio/análise , Polímeros/química , Compostos de Sulfidrila/química , Complexos de Coordenação/síntese química , Corantes Fluorescentes/química , Glucose/análise , Glucose Oxidase/metabolismo , Limite de Detecção , Nanotubos/química , Fenantrolinas/química , Polímeros/síntese química , Rodaminas/química , Espectrometria de Fluorescência
5.
Talanta ; 170: 74-80, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28501216

RESUMO

A new fluorescent sensing platform based on ultrathin metal-organic framework (MOF) nanosheets (MnDMS) was prepared from the flexible ligand 2,2-dimethylsuccinate and Mn ions. The MnDMS nanoparticles can be obtained by simply ultrasonication of the MnDMS crystal, and then can be exfoliated into nanosheets by Li-intercalation method. The MnDMS nanosheets can be easily assembled with biological probes, leading to efficient fluorescence quenching of the fluorophore tagged ssDNA and microRNA (miRNA). By using a hybridization chain reaction (HCR) strategy, the fluorescence signal can be obviously amplified. A good linearity was obtained from 1 pM to 200 pM of target ssDNA, with a detection limit of 0.2 pM. The HCR/MnDMS system provides an effective way to monitor miRNA in living cells. Therefore, the MnDMS nanosheets can be used as a new kind of platform in biomedical sensing applications.


Assuntos
DNA/metabolismo , Espaço Intracelular/metabolismo , Estruturas Metalorgânicas/química , MicroRNAs/metabolismo , Nanoestruturas/química , Nanotecnologia/instrumentação , DNA/química , Humanos , Modelos Lineares , Células MCF-7 , Manganês/química , MicroRNAs/química , Modelos Moleculares , Conformação de Ácido Nucleico , Sonicação , Succinatos/química
6.
J Agric Food Chem ; 65(17): 3481-3489, 2017 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-28436225

RESUMO

Respiratory syncytial virus (RSV) is one of the most common respiratory pathogens. Immoderate inflammation plays a great role in causing RSV-induced diseases. In the present study, watsonianone A, isolated from the fruit of Rhodomyrtus tomentosa (Ait.) Hassk, was found to show a good inhibitory effect on RSV-induced NO production, with a half-maximal inhibitory concentration of 37.2 ± 1.6 µM. Enzyme-linked immunosorbent assay and fluorescence quantitative polymerase chain reaction analyses indicated that watsonianone A markedly reduced both mRNA and protein levels of tumor necrosis factor α, interleukin 6, and monocyte chemoattractant protein 1 in RSV-infected RAW264.7 cells. Mechanistically, watsonianone A inhibited nuclear factor κB (NF-κB) activation by suppressing IκBα phosphorylation. Further analysis revealed that watsonianone A activated the thioredoxin system and decreased intracellular reactive oxygen species (ROS) levels, which are closely associated with NF-κB activation in RSV-infected cells. These results reveal that watsonianone A can attenuate RSV-induced inflammation via the suppression of ROS-sensitive inflammatory signaling.


Assuntos
Cicloexanonas/farmacologia , Frutas/química , Myrtaceae/química , Extratos Vegetais/farmacologia , Infecções por Vírus Respiratório Sincicial/imunologia , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Humanos , Proteínas I-kappa B/genética , Proteínas I-kappa B/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , NF-kappa B/genética , NF-kappa B/imunologia , Espécies Reativas de Oxigênio/imunologia , Infecções por Vírus Respiratório Sincicial/tratamento farmacológico , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sinciciais Respiratórios/fisiologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
7.
Int J Ophthalmol ; 9(1): 81-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26949615

RESUMO

AIM: To assess quantitative changes of the macula in diabetic eyes after cataract surgery using optical coherence tomography (OCT) and to estimate the incidence of development or worsening of macular edema (ME) in diabetic eyes with or without pre-existing ME. METHODS: In this prospective, observational study, 92 eyes of 60 diabetic patients who underwent cataract surgery were evaluated before surgery and 1, 3mo after surgery using OCT. Macular thickness was measured with OCT at nine macular subfields defined by the 9 zones early treatment of diabetic retinopathy study (ETDRS), as well as total macular volume obtained by OCT at 1, 3mo after surgery were compared with baseline features obtained before surgery. In addition, the incidence of development or worsening of ME was analyzed in diabetic eyes with or without pre-existing ME. RESULTS: The central subfield mean thickness increased 21.0 µm and 25.5 µm at 1, 3mo follow-up, respectively (P<0.01). The average thickness of inner ring and outer ring increased 14.2 µm and 9.5 µm at 1mo, 18.2 µm and 12.9 µm at 3mo. Central-involved ME developed in 12 eyes at 3mo, including 4 eyes with pre-existing central-involved and 8 eyes with pre-existing non-central involved ME. Pre-existing diabetic macular edema (DME) was significantly associated with central-involved ME development (P<0.001). CONCLUSION: A statistically significant increase could be detected in the central subfield as well as perifoveal and parafoveal sectors though the increase was mild. And eyes with pre-operative DME prior to cataract surgery are at higher risk for developing central-involved ME.

8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(5): 1222-7, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26415432

RESUMO

Phenol is an important chemical engineering material and ubiquitous in industry wastewater, its existence has become a thorny issue in many developed and developing country. More and more stringent standards for effluent all over the world with human realizing the toxicity of phenol have been announced. Many advanced biological methods are applied to industrial wastewater treatment with low cost, high efficiency and no secondary pollution, but the screening of function microorganisms is certain cumbersome process. In our study a rapid procedure devised for screening bacteria on solid medium can degrade phenol coupled with attenuated total reflection fourier transform infrared (ATR-FTIR) which is a detection method has the characteristics of efficient, fast, high fingerprint were used. Principal component analysis (PCA) is a method in common use to extract fingerprint peaks effectively, it couples with partial least squares (PLS) statistical method could establish a credible model. The model we created using PCA-PLS can reach 99. 5% of coefficient determination and validation data get 99. 4%, which shows the promising fitness and forecasting of the model. The high fitting model is used for predicting the concentration of phenol at solid medium where the bacteria were grown. The highly consistent result of two screening methods, solid cultural with ATR-FTIR detected and traditional liquid cultural detected by GC methods, suggests the former can rapid isolate the bacteria which can degrade substrates as well as traditional cumbersome liquid cultural method. Many hazardous substrates widely existed in industry wastewater, most of them has specialize fingerprint peaks detected by ATR-FTIR, thereby this detected method could be used as a rapid detection for isolation of functional microorganisms those can degrade many other toxic substrates.


Assuntos
Bactérias/isolamento & purificação , Fenol/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Bactérias/metabolismo , Análise dos Mínimos Quadrados , Águas Residuárias
9.
Anal Chim Acta ; 868: 36-44, 2015 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-25813232

RESUMO

Rapid and efficient characterization and identification of pathogens at the strain level is of key importance for epidemiologic investigations, which still remains a challenge. In this work, solvothermically Fe3O4-COOH@MIL-101 composites were fabricated by in situ crystallization approach. The composites combine the excellent properties of both chromium (III) terephthalate (MIL-101) and carboxylic-functionalized magnetite (Fe3O4-COOH) particles and possess the efficient peptides/proteins enrichment properties and magnetic responsiveness. Fe3O4-COOH@MIL-101 composites as magnetic solid phase extraction materials were used to increase the discriminatory power of MALDI-TOF MS profiles. BSA tryptic peptides at a low concentration of 0.25 fmol µL(-1) could be detected by MALDI-TOF MS. In addition, Fe3O4-COOH@MIL-101 composites were successfully applied in the selective enrichment of the protein biomarkers from bacterial cell lysates and discrimination of Escherichia coli at the strain level. This work provides the possibility for wide applications of magnetic MOFs to discriminate pathogens below the species level.


Assuntos
Escherichia coli/isolamento & purificação , Imãs/química , Animais , Proteínas de Bactérias/química , Biomarcadores/química , Bovinos , Técnicas de Química Sintética , Escherichia coli/química , Óxido Ferroso-Férrico/síntese química , Óxido Ferroso-Férrico/química , Peptídeos/química , Especificidade da Espécie
10.
Anal Chim Acta ; 832: 58-64, 2014 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-24890695

RESUMO

Novel hydrophilic microparticles containing ß-cyclodextrin (ß-CD) were prepared via one-pot synthesis using reversible addition-fragmentation chain-transfer (RAFT) precipitation polymerization, a "controlled/living" radical polymerization technique. The polymerization was initiated by hydrophilic macromolecular chain-transfer agent [poly(2-hydroxyethyl methacrylate), PHEMA]. The hydrophilic PHEMA on the surface of microparticles can well improve their surface hydrophilicity and lead to their biological compatibility. As chiral restricted access material (RAM), the hydrophilic microparticles can be used for determination of enantiomers in biological samples with direct injection via HPLC analysis.


Assuntos
Cromatografia Líquida/métodos , Animais , Precipitação Química , Humanos , Microscopia Eletrônica de Varredura , Leite/química , Estrutura Molecular , Praguicidas/química , Preparações Farmacêuticas/sangue , Preparações Farmacêuticas/química , Polimerização
11.
J Mol Model ; 19(3): 1205-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23160935

RESUMO

The possibility of a new endohedral fullerene with a trapped aluminum carbide cluster, Al(4)C@C(80)-I( h ), was theoretical investigated. The geometries and electronic properties of it were investigated using density functional theory methods. The Al(4)C unit formally transfers six electrons to the C(80) cage which induces stabilization of Al(4)C@C(80). A favorable binding energy, relatively large HOMO-LUMO gap, electron affinities and ionization potentials suggested the Al(4)C@C(80) is rather stable. The analysis of vertical ionization potential and vertical electron affinity indicate Al(4)C@C(80) is a good electron acceptor.

12.
Zhonghua Nan Ke Xue ; 12(8): 685-8, 2006 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-16970153

RESUMO

OBJECTIVE: To study the effect of endogenous carbon monoxide (CO) on the smooth muscle function of the dog penile corpus cavernosum in vitro. METHODS: Tissue bioassay was used to measure the corpus cavernosum muscle contraction and relaxation. The production of CO was induced in the corpus cavernosum smooth muscle, and the effect of CO on the penile corpus cavernosum smooth muscle pre-contracted by phenylephrine (PE) was determined. RESULTS: Chlorinous hemoglobin could relax the smooth muscle stripes pre-contracted by 10 micromol/L PE. A dose-dependent relaxation was observed. The relaxation responses by 10 -100 micromol/L chlorinous hemoglobin were significant compared with the control group (P < 0. 01). The pretreatment of the muscle stripes with ZnPP-IX or methylthioninium significantly reduced the relaxing effect of chlorinous hemoglobin (P < 0.01). CONCLUSION: The relaxing effect of endogenous CO on the smooth muscle of the penile corpus cavernosum depends on the concentration of endogenous CO. The underlying mechanism may involve the pathway from CO to cGMP production.


Assuntos
Monóxido de Carbono/fisiologia , Músculo Liso/fisiologia , Animais , Cães , Relação Dose-Resposta a Droga , Hemina/farmacologia , Técnicas In Vitro , Masculino , Músculo Liso/efeitos dos fármacos , Ereção Peniana/efeitos dos fármacos , Ereção Peniana/fisiologia , Pênis/efeitos dos fármacos , Pênis/fisiologia
13.
J Virol ; 78(22): 12576-90, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15507645

RESUMO

Here we report the complete genome sequence of Singapore grouper iridovirus (SGIV). Sequencing of the random shotgun and restriction endonuclease genomic libraries showed that the entire SGIV genome consists of 140,131 nucleotide bp. One hundred sixty-two open reading frames (ORFs) from the sense and antisense DNA strands, coding for lengths varying from 41 to 1,268 amino acids, were identified. Computer-assisted analyses of the deduced amino acid sequences revealed that 77 of the ORFs exhibited homologies to known virus genes, 23 of which matched functional iridovirus proteins. Forty-two putative conserved domains or signatures were detected in the National Center for Biotechnology Information CD-Search database and PROSITE database. An assortment of enzyme activities involved in DNA replication, transcription, nucleotide metabolism, cell signaling, etc., were identified. Viruses were cultured on a cell line derived from the embryonated egg of the grouper Epinephelus tauvina, isolated, and purified by sucrose gradient ultracentrifugation. The protein extract from the purified virions was analyzed by polyacrylamide gel electrophoresis followed by in-gel digestion of protein bands. Matrix-assisted laser desorption ionization-time of flight mass spectrometry and database searching led to identification of 26 proteins. Twenty of these represented novel or previously unidentified genes, which were further confirmed by reverse transcription-PCR (RT-PCR) and DNA sequencing of their respective RT-PCR products.


Assuntos
Genoma Viral , Iridovirus/genética , Perciformes/virologia , Proteômica , Proteínas Virais/análise , Animais , Sequência de Bases , Reparo do DNA , Replicação do DNA , Genômica , Iridovirus/classificação , Dados de Sequência Molecular , Filogenia , RNA Mensageiro/biossíntese , Sequências Repetitivas de Ácido Nucleico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Transcrição Gênica
14.
Artigo em Inglês | MEDLINE | ID: mdl-12115012

RESUMO

It was demonstrated by oxygen equilibrium curve that the pyridoxal 5-phosphate(PLP) modified porcine deoxyhemoglobin(pHbbeta) had lower oxygen affinity than that of stroma-free porcine hemoglobin(pHb). Accourding to analysis of SDS-PAGE, the porcine hemoglobin derivatives were not cross-linked between its subunits. A conjugate was synthesized between pHbbeta and p-toluenesolfonyl chloride-actived dextran. The oxygen affinity of Dx-pHbbeta was high than that of pHbbeta, but still lower than that of pHb. Judged by cellulose acetate film electrophoresis, the mobility of Dx-pHbbeta was apparently different from that of pHbbeta. Dx-pHbbeta has characterized absorbance peak in UV spectrum, which can be used to analysis the binding ratio between Dx and pHbbeta.

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