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1.
Talanta ; 235: 122803, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34517661

RESUMO

An electrochemical biosensor for highly sensitive detection of tobacco mosaic virus (TMV) RNA (tRNA) based on click chemistry and photoinduced atom transfer radical polymerization (photoATRP) is developed for the first time. Herein, tRNA is recognized and captured by hairpin DNA immobilized on the gold electrode surface by Au-S self-assembly. Propyl 2-bromoisobutyrate (PBIB), a photoATRP initiator containing an alkyne group, is conjugated to the azide group of hairpin DNA via a Cu(I)-catalyzed azidoalkyl cyclization reaction (CuAAC). Under the irradiation of 470 nm blue light, photoATRP is activated by the photoredox catalyst (eosin Y, EY), resulting in the formation of a large number of electroactive probes (ferrocenylmethyl methacrylate, FMMA), which significantly amplifies the signal. Under the optimal experimental parameters, the strategy has a wide linear detection (0.1 pM-10 nM) (R2 = 0.995) with a limit of detection (LOD) as low as 3.5 fM. In addition, the biosensor also exhibited good selectivity for mismatched bases, excellent stability and reproducibility. Moreover, satisfactory result was achieved when the biosensor was applied to the detection of tRNA from healthy rehmannia total RNA extracts, which demonstrates the great potential of the method in the practical detection of TMV.


Assuntos
Técnicas Biossensoriais , Vírus do Mosaico do Tabaco , Química Click , Técnicas Eletroquímicas , Limite de Detecção , Polimerização , RNA , Reprodutibilidade dos Testes
2.
Biosens Bioelectron ; 194: 113600, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34481242

RESUMO

A sensitive electrogenerated chemiluminescence (ECL) biosensor for glucose was developed based on in situ growth of TiO2 nanowires on Ti3C2 MXenes (TiO2-Ti3C2) as the nanoplatform. Via tuning the alkaline oxidation time, different amount of TiO2 nanowires can be found on MXenes. An ECL biosensor for glucose was constructed by covalent immobilization of glucose oxidase (GODx) on the glycine functional TiO2-Ti3C2 surface, with the ECL signal depending on the in-situ formation of H2O2 via the specifically catalysis of glucose by GODx, resulting in the apparent increase of ECL signal. The TiO2-Ti3C2 can also act as the catalyst for the oxidation of H2O2 into O2 to enhance the ECL of luminol. Based on this strategy, a highly sensitive ECL biosensor for glucose was obtained in wide concentration range of 20 nM-12 mM with a low detection limit of 1.2 nM (S/N = 3). The synergistic effects of large surface area, excellent conductivity, and high catalytic activity of the TiO2-Ti3C2 make the sensor highly sensitive toward glucose; the specific enzyme catalysis reaction promises excellent selectivity of the ECL sensor. The proposed biosensor has been employed to detect glucose in human serum, fruits, and sweat samples with excellent performance, providing a universal approach for glucose in various samples, which shows great prospect in clinical diagnostics and wearable sensors.

3.
Adv Healthc Mater ; : e2101722, 2021 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-34569171

RESUMO

Most injectable hydrogels used in biomedical engineering have unsatisfactory and untunable mechanical properties, making it difficult to match them with the mechanical strengths of different tissues and organs, which can cause a series of adverse consequences such as immune rejection and soft tissue contusion. In this contribution, dopamine-modified hyaluronic acid (HA-DA) is developed as the backbone for an injectable hydrogel using a catechol-Fe3+ coordination crosslinking strategy. Due to dynamic physical crosslinking, the hydrogel can be easily injected through a single syringe. Into the hydrogel, black phosphorous nanosheets loaded with a Zr-based porphyrinic metal-organic framework (PCN@BP) are introduced that could generate reactive oxygen species (ROS) under 660 nm laser irradiation, this promotes the oxidative coupling of dopamine in the presence of the ROS, introducing in situ chemical crosslinking into the hydrogel. A physical/chemical double-crosslinked hydrogel is obtained, effectively improving the hydrogel's mechanical properties, which are tuned in situ by adjusting the irradiation time to match the mechanical modulus of different biological tissues. Combining the excellent photothermal properties and photodynamic performance of the PCN@BP nanosheets yields effective sterilization under mild conditions (below 50 °C, low ROS production). The results show that this hydrogel is an excellent multifunctional wound dressing.

4.
Food Chem ; 370: 130975, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34507207

RESUMO

Hickory (Carya cathayensis) nuts contain higher amount of lipids, and possess high nutritional value and substantial health benefits. However, their lipid composition and dynamic changes during embryogenesis have not been thoroughly investigated. Therefore, lipidomics profile and lipid dynamic changes during embryonic development were analyzed using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Totally, 544 kinds of lipids were identified in mature hickory nuts with higher proportions of glycerolipids (59.94%) and glycerophospholipids (38.66%). Notably, diacylglycerols showed gradual uptrends, which corresponded with total glycerolipid and glycerophospholipid at middle and late stage of embryogenesis, suggesting the pivotal role of diacylglycerols in the accumulation of glycerolipids and glycerophospholipids. Moreover, triacylglycerols, diacylglycerols, phosphatidylethanolamines and phosphatidylcholines had high relative content with abundance of unsaturated fatty acids, specifically oleic acid, linoleic acid and linolenic acid, localized mainly at sn-2 lipid position. Together, our study provides innovative perspectives for studying the nutritional benefits of hickory nut lipids.

5.
Exp Clin Transplant ; 2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34387153

RESUMO

OBJECTIVES: Antithymocyte globulin is extensively used for prophylaxis of graft-versus-host disease in patients undergoing haploidentical hematopoietic stem cell transplantation. However, different doses of antithymocyte globulin are administered in clinical practice. This study aimed to identify the optimal dose of antithymocyte globulin (thymoglobulin) in haploidentical hematopoietic stem cell transplantation. MATERIALS AND METHODS: We retrospectively analyzed the effects of 10 mg/kg (2.5 mg/kg on days -5 to -2) versus 7.5 mg/kg thymoglobulin (2.5 mg/kg on days -4 to -2) on patients receiving haploidentical hematopoietic stem cell transplantation with myeloablative conditioning. RESULTS: We observed significant differences between the 2 treatment groups with regard to cumulative incidence of grade II to IV acute graft-versus-host disease (15.3% vs 14.6%; P = .93) and 3-year chronic graft-versus-host disease (12.1% vs 14.3%; P = .77). The probabilities of 3-year overall survival (68.9% vs 73.5%; P = .98) and graft-versus-host disease-free/relapse-free survival (66.7% vs 53.1%; P = .14) were comparable between the 2 groups. However, there was a trend for lower cumulative incidence of hemorrhagic cystitis in the 7.5 mg/kg treatment group compared with the 10 mg/kg treatment group (40.7% vs 24.4%; P = .07). CONCLUSIONS: For patients who received a reduced dose of antithymocyte globulin (7.5 vs 10 mg/kg), there was no impaired effect on prophylaxis of graft-versus-host disease, with a trend of reduced incidence of hemorrhagic cystitis. Further studies of the 7.5 mg/kg dose of antithymocyte globulin are warranted for patients receiving haploidentical hematopoietic stem cell transplantation.

6.
Microbiome ; 9(1): 171, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34389047

RESUMO

BACKGROUND: Plants live with diverse microbial communities which profoundly affect multiple facets of host performance, but if and how host development impacts the assembly, functions and microbial interactions of crop microbiomes are poorly understood. Here we examined both bacterial and fungal communities across soils, epiphytic and endophytic niches of leaf and root, and plastic leaf of fake plant (representing environment-originating microbes) at three developmental stages of maize at two contrasting sites, and further explored the potential function of phylloplane microbiomes based on metagenomics. RESULTS: Our results suggested that plant developmental stage had a much stronger influence on the microbial diversity, composition and interkingdom networks in plant compartments than in soils, with the strongest effect in the phylloplane. Phylloplane microbiomes were co-shaped by both plant growth and seasonal environmental factors, with the air (represented by fake plants) as its important source. Further, we found that bacterial communities in plant compartments were more strongly driven by deterministic processes at the early stage but a similar pattern was for fungal communities at the late stage. Moreover, bacterial taxa played a more important role in microbial interkingdom network and crop yield prediction at the early stage, while fungal taxa did so at the late stage. Metagenomic analyses further indicated that phylloplane microbiomes possessed higher functional diversity at the early stage than the late stage, with functional genes related to nutrient provision enriched at the early stage and N assimilation and C degradation enriched at the late stage. Coincidently, more abundant beneficial bacterial taxa like Actinobacteria, Burkholderiaceae and Rhizobiaceae in plant microbiomes were observed at the early stage, but more saprophytic fungi at the late stage. CONCLUSIONS: Our results suggest that host developmental stage profoundly influences plant microbiome assembly and functions, and the bacterial and fungal microbiomes take a differentiated ecological role at different stages of plant development. This study provides empirical evidence for host exerting strong effect on plant microbiomes by deterministic selection during plant growth and development. These findings have implications for the development of future tools to manipulate microbiome for sustainable increase in primary productivity. Video Abstract.


Assuntos
Microbiota , Zea mays , Bactérias/genética , Fungos/genética , Microbiota/genética , Raízes de Plantas
7.
J Sep Sci ; 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34453482

RESUMO

The separation and purification of biomacromolecules such as nucleic acid is a perpetual topic in separation processes and bioengineering (fine chemicals, biopharmaceutical engineering, diagnostics, and biological characterization). In principle, the solid-phase extraction for nucleic acid exhibits efficient phase separation, low pollution risk, and small sample demand, compared to the conventional liquid-phase extraction. Herein, solid-phase extraction methods are systematically reviewed to outline research progress and explore additional solid-phase sorbents and devices for novel, flexible, and high-efficiency nucleic acid separation processes. The functional materials capture nucleic acid, magnetic and magnetic-free solid-phase extraction methods, separation device design and optimization, and high-throughput automatable applications based on high-performance solid-phase extraction are summarized. Finally, the current challenges and promising topics are discussed.

8.
Acta Cytol ; 65(5): 368-376, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34350849

RESUMO

INTRODUCTION: There are few studies on the role of puncture feeling in thyroid nodules during ultrasound-guided fine-needle aspiration cytology (US-FNAC), although it is expected to become a new predictive technique. We aimed to analyze the importance of puncture feeling in combination with US-FNAC and investigate whether it can be used as an indicator to predict the nature of thyroid nodules. MATERIALS AND METHODS: From January 1, 2018, to October 31, 2020, a total of 623 thyroid nodules were included. Puncture feeling was classified as "soft," "hard," or "hard with grittiness." The correlation between puncture feeling and postoperative pathology and the diagnostic value of FNAC combined with puncture feeling were analyzed, and the influence of thyroid nodule size on puncture feeling, FNAC, and FNAC combined with puncture feeling was studied. We further explored the correlation between puncture feeling and histopathology in Bethesda III and IV thyroid nodules. RESULTS: There was a significant correlation between puncture feeling and postoperative pathology (p < 0.001). The sensitivity, negative predictive value, and total coincidence rate of US-FNAC combined with puncture feeling for the diagnosis of thyroid nodules were higher than those of US-FNAC alone (96.1, 83.6, and 94.7% vs. 89.0, 65.5, and 89.7%, respectively). Thyroid nodule size was the influencing factor for puncture feeling, FNAC, and FNAC combined with puncture feeling (p < 0.05 for all). The area under the curve for puncture feeling, FNAC, and FNAC combined with puncture feeling for thyroid nodules of size ≤1 cm was greater than for modules of size >1 cm. Puncture feeling was of great value in diagnosing Bethesda III thyroid nodules (p < 0.001), and all Bethesda IV thyroid nodules had puncture feeling of soft. CONCLUSION: Puncture feeling is of great value during US-FNAC. "Hard" and "hard with grittiness" were indicators for malignancy, while "soft" indicated that the thyroid nodule was likely to be benign. The diagnostic value of US-FNAC combined with puncture feeling for thyroid nodules is higher than US-FNAC alone, especially when nodule size is ≤1 cm. Puncture feeling is of great value in predicting the nature of Bethesda III thyroid nodules.


Assuntos
Punções , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/patologia , Biópsia por Agulha Fina/métodos , Citodiagnóstico/métodos , Técnicas Citológicas/métodos , Humanos , Biópsia Guiada por Imagem/métodos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Ultrassonografia/métodos
9.
Nat Commun ; 12(1): 5134, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34446734

RESUMO

The gastrointestinal tract may be a site of origin for α-synuclein pathology in idiopathic Parkinson's disease (PD). Disruption of the autophagy-lysosome pathway (ALP) may contribute to α-synuclein aggregation. Here we examined epigenetic alterations in the ALP in the appendix by deep sequencing DNA methylation at 521 ALP genes. We identified aberrant methylation at 928 cytosines affecting 326 ALP genes in the appendix of individuals with PD and widespread hypermethylation that is also seen in the brain of individuals with PD. In mice, we find that DNA methylation changes at ALP genes induced by chronic gut inflammation are greatly exacerbated by α-synuclein pathology. DNA methylation changes at ALP genes induced by synucleinopathy are associated with the ALP abnormalities observed in the appendix of individuals with PD specifically involving lysosomal genes. Our work identifies epigenetic dysregulation of the ALP which may suggest a potential mechanism for accumulation of α-synuclein pathology in idiopathic PD.


Assuntos
Apêndice/metabolismo , Autofagia , Epigênese Genética , Lisossomos/metabolismo , Doença de Parkinson/metabolismo , Animais , Apêndice/química , Encéfalo/metabolismo , Encéfalo/patologia , Metilação de DNA , Feminino , Humanos , Lisossomos/química , Lisossomos/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Doença de Parkinson/genética , Doença de Parkinson/patologia , Agregados Proteicos , alfa-Sinucleína/química , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
10.
Tree Physiol ; 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34409460

RESUMO

Hickory (Carya cathayensis Sarg.) is an extraordinary nut-bearing deciduous arbor with high content of oil in its embryo. However, it is greatly unknown about the molecular mechanism underlying high oil accumulation. Here, we reported that the lipid droplets and oil accumulation gradually increased with the embryo development and the oil content was up to about 76% at the maturity. Furthermore, transcriptome and proteome analysis of developing hickory embryo identified 32,907 genes and 9,857 proteins. Time-series analysis of gene expressions showed that these genes were divided into 12 clusters and lipid metabolism-related genes were enriched in cluster 3 with the highest expression levels at 95 days after pollination (S2). Differentially expressed genes and proteins indicated high correlation and both were enriched in the lipid metabolism. Notably, the genes involved in biosynthesis, transport of fatty acid/lipid and lipid droplets formation had high expression levels at S2, while the expression levels of other genes required for suberin/wax/cutin biosynthesis and lipid degradation were very low at all the sampling time points, ultimately promoting the accumulation of oil. qRT-PCR analysis also verified the results of RNA-seq. The co-regulatory networks of lipid metabolism were further constructed and WRINKLED1 (WRI1) was a core transcriptional factor located in the nucleus. Noteworthily, CcWRI1A/B could directly activate the expression of some genes (CcBCCP2A, CcBCCP2B, CcFATA and CcFAD3) required for fatty acid synthesis. These results provided in-depth evidence for revealing the molecular mechanism of high oil accumulation in hickory embryo.

11.
J Chromatogr Sci ; 2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34343279

RESUMO

The pomace of sea buckthorn berries is usually discarded when transforming into nonalcoholic or alcoholic beverages, jellies, jams, juices, candies and dairy products. Here, we established a promising approach for one step separation of five flavonoids from the waste pomace of sea buckthorn berries through counter-current chromatography. The crude extract of waste pomace of sea buckthorn berries after juicing was injected into counter-current chromatography with hexane/ethyl acetate/ethanol/water (v/v/v/v, 5:7:5:7) as the solvent system. As a result, five flavonoids, including quercetin, laricitrin, isorhamnetin-7-O-rhamnoside, kaempferol and isorhamnetin, were obtained in a single step separation. Our finding showed that ethanol is a good substitute for methanol to regulate the partition coefficient in hexane/ethyl acetate/ methanol/water system. This study provided a significant measure to utilize the waste pomace of Sea buckthorn berries.

12.
Sci Adv ; 7(31)2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34330711

RESUMO

Sunlight-associated melanomas carry a unique C-to-T mutation signature. UVB radiation induces cyclobutane pyrimidine dimers (CPDs) as the major form of DNA damage, but the mechanism of how CPDs cause mutations is unclear. To map CPDs at single-base resolution genome wide, we developed the circle damage sequencing (circle-damage-seq) method. In human cells, CPDs form preferentially in a tetranucleotide sequence context (5'-Py-T<>Py-T/A), but this alone does not explain the tumor mutation patterns. To test whether mutations arise at CPDs by cytosine deamination, we specifically mapped UVB-induced cytosine-deaminated CPDs. Transcription start sites (TSSs) were protected from CPDs and deaminated CPDs, but both lesions were enriched immediately upstream of the TSS, suggesting a mutation-promoting role of bound transcription factors. Most importantly, the genomic dinucleotide and trinucleotide sequence specificity of deaminated CPDs matched the prominent mutation signature of melanomas. Our data identify the cytosine-deaminated CPD as the leading premutagenic lesion responsible for mutations in melanomas.

13.
J Hazard Mater ; 419: 126443, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34175704

RESUMO

Two-dimensional luminescence metal organic framework nanosheets (LMOF) named NH2-CuMOFs were synthesized using Cu (II) nodes coordinated with negatively charged 2-aminoterephthalic acid (NH2-BDC) via a bottom-up strategy, which were first used as the fluorescent probes for the detection of chromium Cr (VI). The nanosheets possess stable fluorescence with the maximum emission wavelength of 436 nm at excitation of 338 nm that can be effectively quenched by hexavalent chromium Cr (VI). The NH2-CuMOFs nanosheets show superior advantage over the linker of NH2-BDC for the excellent selectivity to Cr (Ⅵ) without the interferences of other metal ions. The mechanism investigation suggested that the sensitive detection of Cr (VI) was attributed to the chemical oxidation-reduction (redox) reaction and internal filtration effect (IFE) between Cr (VI) and NH2-CuMOFs nanosheets. Based on this mechanism, the quantitation of Cr (VI) was realized in the linear range of 0.1-20 µM with a detection limit of 18 nM. Moreover, the detection of Cr (VI) in real samples was also conducted with good recovery. This work provides an optical sensing nanoplatform for heavy metal ions based on two-dimensional LMOFs via a novel mechanism integrating chemical redox reaction and IFE, which may promise broad application prospect for two-dimensional luminescence nanosheets.


Assuntos
Estruturas Metalorgânicas , Pontos Quânticos , Cromo , Luminescência , Oxirredução
14.
J Healthc Eng ; 2021: 8872022, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34188792

RESUMO

Objective: The purpose of this study was to observe the dental arch asymmetry in 12-year-olds with normal occlusion during the early permanent dentition stage. Methods: Ninety-two 12-year-old students (46 males and 46 females) who had normal occlusion during early permanent dentition were selected from a junior high school in Tangshan, China. Once per year for three consecutive years, a dental cast was obtained from each subject, and the cast was scanned with a 3D digital scanner (R700 3D). The median palatal plane (MPP) and transverse palatal plane (TPP) were used as the reference plane for the transverse and anteroposterior measurements, respectively. Results: Most of the dental arch asymmetry indicators decreased with age, but these differences were not statistically significant. The values of the midincisal edge of the upper central incisors (U1), midincisal edge of the upper lateral incisors (U2), upper canine cusp tip (U3), upper first premolar buccal cusp tip (U4), upper second premolar buccal cusp tip (U5), upper first molar mesiobuccal cusp tip (U6MB), and upper first molar distobuccal cusp tip (U6DB) to the TPP were 0.019 mm, 0.279 mm, 0.017 mm, 0.016 mm, 0.016 mm, 0.027 mm, and 0.200 mm, respectively; these values were larger in males than in females (P < 0.05). The values of 2-5, 6MB, and 6DB-TPP were 0.154 mm, 0.102 mm, 0.119 mm, 0.259 mm, 0.206 mm, and 0.123 mm, respectively, larger in the mandibular than in the maxillary dental arch (P < 0.05). The values of the midincisal edge of the lower central incisors (L1), midincisal edge of the lower lateral incisors (L2), lower canine cusp tip (L3), lower first premolar buccal cusp tip (L4), lower second premolar buccal cusp tip (L5), lower first molar mesiobuccal cusp tip (L6MB), and lower first molar distobuccal cusp tip (L6DB) to the MPP were 0.399 mm, 0.197 mm, 0.258 mm, 0.248 mm, 0.214 mm, 0.575 mm, and 0.531 mm, respectively, larger than L1-5, L6MB, and L6DB-TPP (P < 0.05). Conclusion: The asymmetry of the dental arch in 12-to-15-year-olds with normal occlusion did not change significantly with age. The anteroposterior asymmetry of the maxillary dental arch is larger in males than in females. With the exception of the central incisor, the anteroposterior asymmetry of the mandibular dental arch is larger than that of the maxillary dental arch. The transverse asymmetry of the mandibular dental arch is larger than the anteroposterior asymmetry.

15.
J Agric Food Chem ; 69(26): 7303-7312, 2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34160203

RESUMO

Formaldehyde (HCHO) pollution is a scientific problem of general concern and has aroused wide attention. In this work, a fluorometric method for sensitive detection of formaldehyde was developed based on the oxidase-mimicking activity of MnO2 nanosheets in the presence of o-phenylenediamine (OPD). The MnO2 nanosheets were prepared by the bottom-up approach using manganese salt as the precursor, followed by the exfoliation with bovine serum albumin. The as-prepared MnO2 nanosheets displayed excellent oxidase-mimicking activity, and can be used as the nanoplatform for sensing in fluorometric analysis. OPD was used as a typical substrate because MnO2 nanosheets can catalyze the oxidation of OPD to generate yellow 2,3-diaminophenazine (DAP), which can emit bright yellow fluorescence at the wavelength of 560 nm. While in the presence of formaldehyde, the fluorescence was greatly quenched because formaldehyde can react with OPD to form Schiff bases that decreased the oxidation reaction of OPD to DAP. The main mechanism and the selectivity of the platform were studied. As a result, formaldehyde can be sensitively detected in a wide linear range of 0.8-100 µM with the detection limit as low as 6.2 × 10-8 M. The platform can be used for the detection of formaldehyde in air, beer, and various food samples with good performance. This work not only expands the application of MnO2 nanosheets in fluorescence sensing, but also provides a sensitive and selective method for the detection of formaldehyde in various samples via a new mechanism.


Assuntos
Compostos de Manganês , Oxirredutases , Catálise , Formaldeído , Óxidos
16.
Mol Neurobiol ; 58(9): 4376-4391, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34014435

RESUMO

The transport system in cochlear hair cells (HCs) is important for their function, and the kinesin family of proteins transports numerous cellular cargos via the microtubule network in the cytoplasm. Here, we found that Klc2 (kinesin light chain 2), the light chain of kinesin-1 that mediates cargo binding and regulates kinesin-1 motility, is essential for cochlear function. We generated mice lacking Klc2, and they suffered from low-frequency hearing loss as early as 1 month of age. We demonstrated that deficiency of Klc2 resulted in abnormal transport of mitochondria and the down-regulation of the GABAA receptor family. In addition, whole-genome sequencing (WGS) of patient showed that KLC2 was related to low-frequency hearing in human. Hence, to explore therapeutic approaches, we developed adeno-associated virus containing the Klc2 wide-type cDNA sequence, and Klc2-null mice delivered virus showed apparent recovery, including decreased ABR threshold and reduced out hair cell (OHC) loss. In summary, we show that the kinesin transport system plays an indispensable and special role in cochlear HC function in mice and human and that mitochondrial localization is essential for HC survival.

17.
Mikrochim Acta ; 188(6): 186, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33978843

RESUMO

Metal-organic framework (UiO-66-NH2)-incorporated organic polymer monolith was prepared by thermal polymerization. By virtue of the superior physical and chemical properties, the UiO-66-NH2-modified organic monolith was then functionalized by chiral selector cellulase via the condensation reaction between the primary amino groups and aldehyde groups. The synthesized materials were characterized by Fourier transform infrared spectroscopy, high-resolution transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectrometry, thermogravimetric analysis, and nitrogen sorption isotherm. The cellulase@poly(glycidyl methacrylate-UiO-66-NH2-ethylene glycol dimethacrylate) (cellulase@poly(GMA-UiO-66-NH2-EDMA)) monolith was applied to enantiomerically separate the basic racemic forms of metoprolol, atenolol, esmolol, bisoprolol, and propranolol. In contrast to the cellulase@poly(GMA-co-EDMA) monolith without UiO-66-NH2, the cellulase@poly(GMA-UiO-66-NH2-EDMA) monolith reveals significantly improved enantiodiscrimination performance for metoprolol (Rs: 0 → 1.67), atenolol (Rs: 0 → 1.50), esmolol (Rs: 0 → 1.52), bisoprolol (Rs: 0 → 0.36), and propranolol (Rs: 0 → 0.44). The immobilization pH of cellulase, buffer pH, UiO-66-NH2 concentration, and the proportion of organic modifier were evaluated in detail with enantiomerically separating chiral molecules. The intra-day, inter-day, column-to-column, and inter-batch precision have been discussed, the result was preferable, and the relative standard deviation (RSD) of separation parameters was <4.3%. Schematic representation of the preparation of a UiO-66-NH2-modified organic polymer monolith for enantioseparating five racemic ß-blockers. UiO-66-NH2 was synthesized and converted into a monolith as the stationary phase. Then, the modified monolith containing cellulase as the chiral selector was applied in a capillary electrochromatography system for enantioseparating chiral drugs.

18.
Biosens Bioelectron ; 183: 113217, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33862395

RESUMO

Organic mercury including methyl-mercury and ethyl-mercury (CH3Hg+ and C2H5Hg+) has high toxicity and bio-accumulation, and thus is easy to generate bio-amplification in food chain. Hence, the specific detection of organic mercury has great significance for objectively assessing the health risk of mercury in seafood. We herein designed an aptamer (AS-T7), which consists of a silver nanoclusters (AgNCs) scaffold sequence (AS) and a T-rich sequence (AT7), for simultaneously synthetizing DNA-templated AgNCs and recognizing organic mercury, and further developed a label-free fluorescent method for the sensitive and specific determination of organic mercury (CH3Hg+ and C2H5Hg+ total concentration) by using DNA-templated AgNCs as signal. Without organic mercury, Ag+ in the mixture of aptamer and Ag+ was bond on AS of aptamer to form AS-templated AgNCs after reduction, and thus emitted strong fluorescence. Whereas, in the presence of organic mercury, CH3Hg+/C2H5Hg+ was bond on AT7 of aptamer to generate photoinduced electron transfer (PET) between CH3Hg+/C2H5Hg+ and AS-templated AgNCs, and thus results in fluorescence quenching of AS-templated AgNCs. The fluorescent method could be used to rapidly detect organic mercury with a detection limit of 5.0 nM (i.e. 1.01 ng Hg/g), which meets the U.S. EPA standard of 0.3 mg/kg (wet). The method was successfully used to detect organic mercury in water and fish muscle with a recovery of 96%-104% and an inter-days RSD (n = 5) < 7%. The success of the study promised a reliable method for rapid and specific detection of organic mercury in environmental and biological samples.


Assuntos
Técnicas Biossensoriais , Mercúrio , Nanopartículas Metálicas , Animais , DNA , Corantes Fluorescentes , Limite de Detecção , Alimentos Marinhos , Prata , Espectrometria de Fluorescência
19.
Aging (Albany NY) ; 13(8): 11336-11351, 2021 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-33833129

RESUMO

This study investigated the effects of transforming growth factor-ß1 (TGF-ß1) and cyclooxygenase-2 (COX-2) on bone morphogenetic protein 9 (BMP9) in mesenchymal stem cells (MSCs). We found that BMP9 increased mRNA levels of TGF-ß1 and COX-2 in C3H10T1/2 cells. BMP9-induced osteogenic markers were enhanced by TGF-ß1 and reduced by TGF-ßRI-specific inhibitor LY364947. BMP9 increased level of p-Smad2/3, which were either enhanced or reduced by COX-2 and its inhibitor NS398. BMP9-induced osteogenic markers were decreased by NS398 and it was partially reversed by TGF-ß1. COX-2 increased BMP9-induced osteogenic marker levels, which almost abolished by LY364947. BMP9-induced bone formation was enhanced by TGF-ß1 but reduced by silencing TGF-ß1 or COX-2. BMP9's osteogenic ability was inhibited by silencing COX-2 but partially reversed by TGF-ß1. TGF-ß1 and COX-2 enhanced activation of p38 signaling, which was induced by BMP9 and reduced by LY364947. The ability of TGF-ß1 to increase the BMP9-induced osteogenic markers was reduced by p38-specific inhibitor, while BMP9-induced TGF-ß1 expression was reduced by NS398, but enhanced by COX-2. Furthermore, CREB interacted with Smad1/5/8 to regulate TGF-ß1 expression in MSCs. These findings suggest that COX-2 overexpression leads to increase BMP9's osteogenic ability, resulting from TGF-ß1 upregulation which then activates p38 signaling in MSCs.


Assuntos
Ciclo-Oxigenase 2/metabolismo , Fator 2 de Diferenciação de Crescimento/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osteogênese/fisiologia , Fator de Crescimento Transformador beta1/metabolismo , Animais , Linhagem Celular , Feminino , Técnicas de Silenciamento de Genes , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Modelos Animais , Receptor do Fator de Crescimento Transformador beta Tipo I/antagonistas & inibidores , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Fator de Crescimento Transformador beta1/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
20.
Expert Rev Mol Diagn ; 21(7): 723-732, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33899643

RESUMO

INTRODUCTION: Rapid and accurate diagnostic approaches are essential for impeding the spread of infectious diseases. This review aims to summarize current progress of clustered regularly interspaced short palindromic repeats (CRISPR)-associated (Cas) systems in the applications for diagnostics of infectious diseases including the ongoing COVID-19 epidemic. AREAS COVERED: In this review, we discuss class 2 CRISPR-Cas biosensing systems-based diagnostics in various emerging and reemerging infectious diseases, CRISPR-Cas systems have created a new era for early diagnostics of infectious diseases, especially with the discovery of the collateral cleavage activity of Cas12 and Cas13. We mainly focus on different CRISPR-Cas effectors for the detection of pathogenic microorganisms as well as provide a detailed explanation of the pros and cons of CRISPR-Cas biosensing systems. In addition, we also introduce future research perspectives. EXPERT COMMENTARY: However, further improvement of newly discovered systems and engineering existing ones should be developed to increase the specificity, sensitivity or stability of the diagnostic tools. It may be a long journey to finish the clinical transition from research use. CRISPR-Cas approaches will emerge as more promising and robust tools for infectious disease diagnosis in the future.


Assuntos
Teste de Ácido Nucleico para COVID-19 , COVID-19 , Sistemas CRISPR-Cas , SARS-CoV-2/genética , COVID-19/diagnóstico , COVID-19/genética , Humanos
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