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1.
Carbohydr Polym ; 227: 115338, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31590863

RESUMO

New sources of AIE materials with good water solubility, biocompatibility, degradability, and mass production are urgently needed. Here, we found that chitosan, a very abundant polysaccharide in nature, has fluorescence emission in both solid and solution states with AIE effect, and explored its multifunctional applications. Chitosan can emit a variety of colors from blue to red at different excitation wavelengths with excellent multicolor imaging capabilities at the cellular level. Utilizing the cationic and antibacterial properties of chitosan, the quantification of bacteria can be achieved through the AIE effect. Concurrently, it can be used as fluorescent probes for multi-channel bacterial imaging via lighting-up bacteria. Furthermore, the chitosan solution exhibits a sensitive quenching response to Fe3+, which can be used as a biosensor for detecting the concentration of Fe3+. These interesting results indicate that chitosan will have broad application prospects as a new class of AIE material.

2.
Luminescence ; 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31667940

RESUMO

The emission wavelength of organic-inorganic hybrid perovskite quantum dots (QDs) can be tuned by controlling reaction time relevant to the halide exchange. It is because halide exchange with different time would lead to different molar ratio of halides in perovskite QDs such as Cl and Br. Here, to research the ligand's effect on the halide exchange, this work synthesized 3-mercaptopropionic acid (MPA)-capped CH3 NH3 PbBrx Cl3-x QDs. It was found that SH- of MPA appeared to inhibit the halide exchange during the reation. Moreover, although the MPA-capped CH3 NH3 PbBrx Cl3-x QDs did not contain the chiral centre, they exhibit the optical rotation. This may provide a method for chirality manipulation of perovskite.

3.
Dalton Trans ; 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31774092

RESUMO

2D materials have strong intermolecular van der Waals forces, and 2D superlattice heterostructures have exhibited many dramatic photo-electrochemical properties for energy conversion and storage. Herein, based on the excellent properties of reduced graphene and superlattice structures, we constructed a 2D flexible superlattice polyoxometalate/rGO heterojunction with enhanced electron-hole separation via interfacial self-assembly engineering to further fabricate DSSCs based on the heterojunction-modified photoanode, which exhibited good electron transport properties. Selecting two kinds of Dawson POMs (P2W15V3, P2W18 and the corresponding heteropoly blue) as the research object, the polyoxometalate superlattice structure was obtained by the self-assembly strategy, and characterized by IR, UV-Vis, XRD, EDX and XPS. The TEM and AFM results indicated that the monolayer POM superlattice structure and superlattice polyoxometalate/rGO heterojunction were successfully obtained. The superlattice P2W18(HPB)/rGO heterojunction was introduced into the DSSCs photoanode, and electrochemical tests indicated that the superlattice polyoxometalate/rGO heterojunction improved the electron-hole separation rate, inhibited the electron recombination, and improved the photoelectric conversion efficiency to 8.09%. The 2D superlattice heterojunction remarkably improved the electrochemical performances of the energy storage and conversion systems.

4.
J Phys Chem Lett ; 10(23): 7318-7323, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31713426

RESUMO

Single-atom catalysts have recently been subject to considerable attention within applied catalysis. However, complications in the preparation of well-defined single-atom model systems have hampered efforts to determine the reaction mechanisms underpinning the reported activity. By means of an atomic layer deposition method utilizing the steric hindrance of the ligands, isolated Fe1O3 motifs were grown on a single-crystal Cu2O(100) surface at densities up to 0.21 sites per surface unit cell. Ambient pressure X-ray photoelectron spectroscopy shows a strong metal-support interaction with Fe in a chemical state close to 3+. Results from scanning tunneling microscopy and density functional calculations demonstrate that isolated Fe1O3 is exclusively formed and occupies a single site per surface unit cell, coordinating to two oxygen atoms from the Cu2O lattice and another through abstraction from O2. The isolated Fe1O3 motif is active for CO oxidation at 473 K. The growth method holds promise for extension to other catalytic systems.

5.
Retina ; 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31725525

RESUMO

PURPOSE: To evaluate the efficacy and primary safety of treating rhegmatogenous retinal detachment (RRD) using foldable capsular vitreous body scleral buckling. METHODS: Five patients with simple RRD were treated with foldable capsular vitreous body scleral buckling. B-ultrasound and fundus photography examining of retina reattachment were used to evaluate the postsurgery efficacy. The safety of the treatment was evaluated based on the occurrence of infection, eye pain, diplopia, elevated intraocular pressure, and other serious postoperative complications after surgery. The observation time after the operation was at least 12 weeks. RESULTS: The simple RRD of all five patients was successfully reattached before being evaluating by B-ultrasound and fundus photography after surgery. Visual acuity was enhanced in two patients who were macularly affected. One patient had temporary diplopia and eye movement limitation after surgery. No other complications were recorded. CONCLUSION: This pilot study determined that foldable capsular vitreous body scleral buckling can be efficacious and safe for simple RRD. The results indicate that this surgery may be a novel alternative to the current extraocular procedures for simple RRD.

6.
Cell Mol Neurobiol ; 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31728694

RESUMO

The mammalian target of rapamycin (mTOR) was reported to regulate cell autophagy and outcomes of several neurological diseases. Mitochondria, which serve as critical organelles in neurons. are also involved in the pathology of neurological diseases. However, the role of mTOR in mitochondrial morphology has not been clarified especially in subarachnoid hemorrhage (SAH). In this study, we established SAH models both in vivo and in vitro. Rapamycin and 3-methyl adenine (3-MA) were then administered to alter mTOR activity. Post-SAH assessment included SAH grading, neurological evaluation, blood-brain barrier (BBB) permeability, brain water content, mitochondrial membrane potential (MMP), mitochondrial morphology, ATP content, cell viability, cytotoxicity, and expression of proteins related to apoptosis and mitochondrial fission. The results showed that (1) neurological deficits, BBB permeability, and brain edema were increased after SAH and that cell viability was exacerbated in brain tissue. (2) Excessive mitochondrial fission was evident based on changes in mitochondrial morphology, while MMP and ATP content were decreased in neurons after SAH. (3) Administration of rapamycin improved the excessive mitochondrial fission and restored mitochondrial function, which subsequently reduced apoptosis. (4) 3-MA showed an adverse effect on mitochondria and aggravated excessive mitochondrial fission and dysfunction in SAH. Neurological deficits and neuronal viability were also exacerbated following the administration of 3-MA. Therefore, our study suggests that mTOR inhibition has neuroprotective effects against neuronal injury after SAH via alleviating excessive mitochondrial fission.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31633335

RESUMO

Lead halide perovskite nanocrystals (NCs) are promising optical materials in many fields. However, their poor moisture stability, significant toxicity, and difficulty to be further functionalized greatly hinder their applications in bioimaging. Here, a universal strategy is demonstrated by simply encapsulating CsPbX3 (X = Cl, Br, I) NCs into phospholipids to achieve CsPbX3-phospholipid micelles (CsPbX3@phospholipid) as probes for multiplex encoding cellular imaging or tumor-targeted imaging. The layer of phospholipids endows CsPbX3 NCs with superior water-resistant characteristics, the ability to be further biofunctionalized, and greatly improved biocompatibility. The CsPbX3@phospholipid micelles exhibited strong luminescence with narrow fwhm in water for more than four months. Specifically, even after being modified with folic acid, the bright fluorescence of the micelles was well retained, which were employed for the targeting of Hela cells. Finally, the greatly reduced toxicity of the CsPbX3@phospholipid micelles was verified using HeLa cells and zebrafish as in vitro and in vivo models, respectively.

8.
MAbs ; 11(8): 1452-1463, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31570042

RESUMO

Protein primary structure is a potential critical quality attribute for biotherapeutics. Identifying and characterizing any sequence variants present is essential for product development. A sequence variant ~11 kDa larger than the expected IgG mass was observed by size-exclusion chromatography and two-dimensional liquid chromatography coupled with online mass spectrometry. Further characterization indicated that the 11 kDa was added to the heavy chain (HC) Fc domain. Despite the relatively large mass addition, only one unknown peptide was detected by peptide mapping. To decipher the sequence, the transcriptome of the manufacturing cell line was characterized by Illumina RNA-seq. Transcriptome reconstruction detected an aberrant fusion transcript, where the light chain (LC) constant domain sequence was fused to the 3' end of the HC transcript. Translation of this fusion transcript generated an extended peptide sequence at the HC C-terminus corresponding to the observed 11 kDa mass addition. Nanopore-based genome sequencing showed multiple copies of the plasmid had integrated in tandem with one copy missing the 5' end of the plasmid, deleting the LC variable domain. The fusion transcript was due to read-through of the HC terminator sequence into the adjacent partial LC gene and an unexpected splicing event between a cryptic splice-donor site at the 3' end of the HC and the splice acceptor site at the 5' end of the LC constant domain. Our study demonstrates that combining protein physicochemical characterization with genomic and transcriptomic analysis of the manufacturing cell line greatly improves the identification of sequence variants and understanding of the underlying molecular mechanisms.

9.
Ying Yong Sheng Tai Xue Bao ; 30(10): 3491-3500, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31621236

RESUMO

The dynamic simulation of cucumber growth and development in sunlight greenhouse can provide technical support for the intelligent management of cucumber production. According to the cucumber response characteristics to light and temperature, the cucumber development module based on the algorithm of clock model was established by using data from four-stage experiment with 'Jinyou 35' as experiment variety in two years. Based on the relationship between the leaf growth and key meteorological factors (temperature and radiation), leaf area index (LAI) module was established with the accumulated product of thermal effectiveness and photosynthetically active radiation (TEP) as independent variables. The simulation module of cucumber dry matter production was established by taking into consideration the double integral of LAI and daily length in photosynthesis per unit leaf area as well as the respiratory expenditure of different organs. Combined with water content of organs, fresh weight simulation module of cucumber organs was constructed. The whole cucumber development and growth simulation model in greenhouse was built based on each sub-module. The model parameters were calibrated and determined. The results showed that root mean square error (RMSE) of simulated values and observed values of four deve-lopment stages (from transplanting date to stretch tendril, to initial flowering, to early harvested and to uprooting), was 3.9-10.5 d. The normalized root mean square error (nRMSE) was 6.5%-28.6%. The coincidence index (D) was 0.79-0.97. The relationship between LAI and TEP was the regression of 'S' type curve. The RMSE of simulated and observed LAI values was 0.19. The nRMSE was 17.2%. The D value was 0.90. The RMSE of dry weight of root, stem, leaf, flower and fruit of the simulated values and observed values were 0.39-8.94 g·m-2. The nRMSE were 10.9%-17.7%. The D values were all above 0.98. The growth and development model of cucumber could accurately simulate the key development period of cucumber, leaf area and the dry and fresh weight of various organs and quantify the growth and development of cucumber in sunlight greenhouse.


Assuntos
Cucumis sativus , Crescimento e Desenvolvimento , Fotossíntese , Folhas de Planta , Luz Solar
10.
Medicine (Baltimore) ; 98(38): e17177, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31567958

RESUMO

Lumbar spinal canal stenosis (LSCS) associated with degenerative scoliosis has being increasingly aware by the public and studied by many researchers. Degenerative changes leading to spinal stenosis can precede a spinal deformity which will develop into the de novo scoliosis. There are few studies focusing on the risk factors contributing to the degenerative lumbar scoliosis (DLS) in lumbar spinal stenosis patients.From September, 2017 to December, 2017, 181 patients who were diagnosed with LSCS in the outpatient department of our hospital were enrolled in this retrospective investigation. The patients were divided into 2 groups: DLS group (Cobb angle >10°) and LSCS group. Sex, age, smoking status (yes or no), occupation (heavy or light labor), body mass index (BMI), bone mineral density (BMD) and radiographic parameters including the lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), thoracic kyphosis (TK), coronal vertical axis, and sagittal vertical axis (SVA) are all evaluated as potential risk factors. Multivariate logistic regression analysis and receiver-operating characteristic curves were used to identify potential risk factors.Forty-five of 181 patients were diagnosed with DLS and involved in the DLS group. There were significant differences between the 2 groups in BMI (P < .001), LL (P = .0046), BMD (P < .001), SVA (P < .001), and TK (P = .047). BMD < -1.85 g/cm (adjusted odds ratio [AOR] 0.030, 95% confidence interval [CI] 0.008-0.107, P < .001), BMI >25.57 kg/m (AOR 1.270, 95% CI 1.040-1.551, P = .019), and SVA >3.98 cm (AOR 3.651, 95% CI 2.226-5.990, P < .001) had good accuracy to predict the formation of degenerative lumbar scoliosis based on degenerative lumbar spinal stenosis.Degenerative lumbar scoliosis has a high incidence in degenerative lumbar spinal stenosis. BMD <-1.85 g/cm, BMI >25.57 kg/m, and SVA >3.98 cm were the potential risk factors for the formation of degenerative lumbar scoliosis based on degenerative lumbar spinal stenosis.


Assuntos
Vértebras Lombares , Escoliose/complicações , Estenose Espinal/etiologia , Estudos Transversais , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Masculino , Pessoa de Meia-Idade , Radiografia , Fatores de Risco , Escoliose/diagnóstico por imagem , Escoliose/patologia , Estenose Espinal/diagnóstico por imagem , Estenose Espinal/patologia
11.
World Neurosurg ; 132: 273-281, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31521758

RESUMO

OBJECTIVE: Although many risk factors for cage retropulsion (CR) after lumbar interbody fusion (LIF) have been described in the literature, they still remain controversial. The purpose of this study is to investigate the risk factors for CR after LIF. METHODS: The literature was searched in PubMed, Cochrane library, and Embase from October 2000 to October 2018. The key words and combinations used in the search included LIF, cage, retropulsion, posterior migration, and risk factors. Only studies with sufficient data to calculate odds ratio for CR were included. Odds ratio and 95% confidence interval were calculated for outcomes via RevMan5.3 and SPSS 22.0. RESULTS: A total of 10 studies were included in this study. Twelve risk factors were assessed by analyzing 4467 patients. The pooled results indicated that a pear-shaped disk and straight cage were significant risk factors for CR. However, factors that had no significant relation with CR were preoperative diagnosis (disk herniation, spinal stenosis, and spondylolisthesis); gender; surgical segments (from L2 to S1); multilevel fusion; and unilateral pedicle screws fixation. CONCLUSIONS: According to current evidence, a pear-shaped disk and straight cage are significant risk factors for CR. However, preoperative diagnosis, gender, multilevel fusion, surgical segments, and unilateral pedicle screws fixation are not the risk factors associated with CR. A revision surgery is needed when neurologic symptoms happen after CR. The conclusion should be consulted cautiously due to the limited number of included studies. Therefore larger-scale studies are still needed to investigate the risk factors for CR.

12.
Phys Chem Chem Phys ; 21(32): 17978-17984, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31385578

RESUMO

Ernzerhof (HSE) hybrid functional approximations based on the density functional theory (DFT) method were applied to investigate the electronic band structures of SnTe. First principles calculations indicate that Ag substitution in SnTe could effectively modify the valence band structures and decrease the energy separation between valence bands, ΔEVBL-Σ, which will enhance the Seebeck coefficient. All the fabricated Ag doped SnTe samples show the same crystal structure as cubic SnTe. Compared to the pure SnTe sample, the Ag doped ones exhibit greatly enhanced thermoelectric performance, especially at high temperatures, with the highest figure-of-merit of around 1.35 achieved at 900 K, by concurrent optimization of the electrical and thermal transport properties.

13.
Biomolecules ; 9(9)2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31466349

RESUMO

Adventitious root (AR) is a kind of later root, which derives from stems and leaf petioles of plants. Many different kinds of small signaling molecules can transmit information between cells of multicellular organisms. It has been found that small molecules can be involved in many growth and development processes of plants, including stomatal movement, flowering, fruit ripening and developing, and AR formation. Therefore, this review focuses on discussing the functions and mechanisms of small signaling molecules in the adventitious rooting process. These compounds, such as nitric oxide (NO), hydrogen gas (H2), hydrogen sulfide (H2S), carbon monoxide (CO), methane (CH4), ethylene (ETH), and hydrogen peroxide (H2O2), can be involved in the induction of AR formation or development. This review also sums the crosstalk between these compounds. Besides, those signaling molecules can regulate the expressions of some genes during AR development, including cell division genes, auxin-related genes, and adventitious rooting-related genes. We conclude that these small-molecule compounds enhance adventitious rooting by regulating antioxidant, water balance, and photosynthetic systems as well as affecting transportation and distribution of auxin, and these compounds further conduct positive effects on horticultural plants under environmental stresses. Hence, the effect of these molecules in plant AR formation and development is definitely a hot issue to explore in the horticultural study now and in the future.

14.
Inorg Chem ; 58(15): 10304-10312, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31328509

RESUMO

In recent years, although low-dimensional hybrid lead halides have received great attention due to the fascinating photoluminescent (PL) properties, the research is still on the early stage and only limited phases have been explored and characterized. Here, by introducing heterometals as mixed structural compositions and optical activity centers, we prepared a series of low-dimensional hybrid heterometallic halides, namely as, [(Me)-DABCO]2Cu2PbI6, [(Me)2-DABCO]2M5Pb2I13 (M = Cu and Ag) and [(Me)2-DABCO]Ag2PbBr6 (Me = methyl group, DABCO = 1,4-diazabicyclo[2.2.2]octane). These hybrid halides feature a low-dimensional 0D [Cu2PbI6]2- cluster, a 1D [M5Pb2I13]4- chain, and a 2D [Ag2PbBr6]2- layer, respectively, on the basis of corner-, edge- and face-sharing connecting of [MX4] tetrahedrons, [PbX5] quadrangular pyramids, and [PbX6] octahedrons. Under the photoexcitation, these hybrid heterometallic halides exhibit deep-red luminescent emissions from 711 to 801 nm with the largest Stocks shift of 395 nm. The temperature-dependent PL emissions, PL lifetime, and theoretical calculations are also investigated to probe into the intrinsic nature of photoluminescent emissions. This work affords new types of hybrid halides by introducing different metal centers to probe into the structural evolution and photoluminescent properties.

15.
Br J Nutr ; : 1-11, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31311615

RESUMO

Excessive intake of high-energy diets is an important cause of most obesity. The intervention of rats with high-fat diet can replicate the ideal animal model for studying the occurrence of human nutritional obesity. Proteomics and bioinformatics analyses can help us to systematically and comprehensively study the effect of high-fat diet on rat liver. In the present study, 4056 proteins were identified in rat liver by using tandem mass tag. A total of 198 proteins were significantly changed, of which 103 were significantly up-regulated and ninety-five were significantly down-regulated. These significant differentially expressed proteins are primarily involved in lipid metabolism and glucose metabolism processes. The intake of a high-fat diet forces the body to maintain physiological balance by regulating these key protein spots to inhibit fatty acid synthesis, promote fatty acid oxidation and accelerate fatty acid degradation. The present study enriches our understanding of metabolic disorders induced by high-fat diets at the protein level.

16.
J Chem Phys ; 150(23): 234703, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31228915

RESUMO

We investigate theoretically the stability of the wetting property, i.e., the contact angle values, as a function of the temperature. We find that the estimated temperature coefficient of the contact angle for the water droplets on an ordered water monolayer on a 100 surface of face-center cubic (FCC) is about one order of magnitude larger than that on a hydrophobic hexagonal surface in the temperature range between 290 K and 350 K, using molecular dynamics simulations. As temperature rises, the number of hydrogen bonds between the ordered water monolayer and the water droplet will increase, which therefore enhances the hydrophilicity of the ordered water monolayer at the FCC model surface. Our work thus provides an easily controllable and reversible way to control the degree of hydrophobicity of various solid surfaces exhibiting a similar wetting property of water droplets on the ordered water monolayer as such particular FCC (100) surfaces.

17.
J Pharm Pharmacol ; 71(9): 1393-1399, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31218683

RESUMO

OBJECTIVE: To evaluate the pharmacological characteristics of SU-011, a novel sodium-dependent glucose co-transporter 2 (SGLT2) inhibitor. METHODS: The in vitro activities of SU-011 were investigated in cell-based assays. The urinary glucose excretion, glucose tolerance and the risk of hypoglycaemia were evaluated in mice. Moreover, the dose-response relationship and chronic pharmacological studies of SU-011 were assessed in streptozotocin (STZ)-induced diabetic model, a STZ-treated model with impaired insulin secretion. KEY FINDINGS: SU-011 is a potential SGLT2 inhibitor with 5.6 nm inhibitory activity for SGLT2 and 1137-fold selectivity for SGLT1. In healthy mice, SU-011 improves the tolerance to a glucose load and promotes the urinary glucose excretion. Besides, SU-011 (10 mg/kg) still exhibited less risk of hypoglycaemia. During chronic treatment, SU-011 exhibited sustained glucose-lowering effect without the side effect of weight gain in STZ-induced diabetic mice. The levels of non-fasting and fasting plasma glucose, glycosylated haemoglobin, food and water intake were significantly decreased in SU-011-treated group. Moreover, SU-011 decreases the plasma levels of interleukin-1ß, tumour necrosis factor-α and C-reactive protein even better than that of dapagliflozin. CONCLUSIONS: All of these results indicated that SU-011 may be effective for the management of diabetes.

18.
ACS Appl Mater Interfaces ; 11(27): 23840-23847, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31251019

RESUMO

Here, we constructed a nanostructured pH/redox dual-responsive supramolecular drug carrier with both aggregation-induced emission (AIE) and Forster resonance energy transfer (FRET) effects, which enabled selective drug release and monitoring drug delivery and release processes. Taking the hyperbranched polyamide amine (H-PAMAM) with intrinsic AIE effects as the core, poly(ethylene glycol) (PEG) was bridged on its periphery by dithiodipropionic acid. Then, through the host-guest interaction of PEG and α-cyclodextrin, the supramolecular nanoparticles with AIE effects were constructed to load the anticancer drug doxorubicin (DOX). The supramolecular assembly has sufficiently large DOX loading due to the abundant cavities formed by branched structures. The hyperbranched core H-PAMAM has strong fluorescence, and the dynamic track of drug carriers and the dynamic drug release process can be monitored by the AIE and FRET effects between H-PAMAM and DOX, respectively. Furthermore, the introduction of disulfide bonds and the pH sensitivity of H-PAMAM enable the achievement of rapid selective release of loaded DOX at the tumor while remaining stable under normal physiological conditions. In vitro cytotoxicity indicates that the drug-loaded supramolecular assembly has a good therapeutic effect on cancer. In addition, the H-PAMAM core is different from the traditional AIE functional group, which has no conjugated structure, such as a benzene ring, thereby providing better biocompatibility. This technology will have broad applications as a new drug delivery system.

19.
Mol Brain ; 12(1): 40, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-31046797

RESUMO

Results of recent genome-wide association studies (GWAS) and whole genome sequencing (WGS) highlighted type II cadherins as risk genes for autism spectrum disorders (ASD). To determine whether these cadherins may be linked to the morphogenesis of ASD-relevant brain regions, in situ hybridization (ISH) experiments were carried out to examine the mRNA expression profiles of two ASD-associated cadherins, Cdh9 and Cdh11, in the developing cerebellum. During the first postnatal week, both Cdh9 and Cdh11 were expressed at high levels in segregated sub-populations of Purkinje cells in the cerebellum, and the expression of both genes was declined as development proceeded. Developmental expression of Cdh11 was largely confined to dorsal lobules (lobules VI/VII) of the vermis as well as the lateral hemisphere area equivalent to the Crus I and Crus II areas in human brains, areas known to mediate high order cognitive functions in adults. Moreover, in lobules VI/VII of the vermis, Cdh9 and Cdh11 were expressed in a complementary pattern with the Cdh11-expressing areas flanked by Cdh9-expressing areas. Interestingly, the high level of Cdh11 expression in the central domain of lobules VI/VII was correlated with a low level of expression of the Purkinje cell marker calbindin, coinciding with a delayed maturation of Purkinje cells in the same area. These findings suggest that these two ASD-associated cadherins may exert distinct but coordinated functions to regulate the wiring of ASD-relevant circuits in the cerebellum.

20.
Proc Natl Acad Sci U S A ; 116(21): 10576-10585, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31064880

RESUMO

Epigenetic markers, such as histone acetylation and DNA methylation, determine chromatin organization. In eukaryotic cells, metabolites from organelles or the cytosol affect epigenetic modifications. However, the relationships between metabolites and epigenetic modifications are not well understood in plants. We found that peroxisomal acyl-CoA oxidase 4 (ACX4), an enzyme in the fatty acid ß-oxidation pathway, is required for suppressing the silencing of some endogenous loci, as well as Pro35S:NPTII in the ProRD29A:LUC/C24 transgenic line. The acx4 mutation reduces nuclear histone acetylation and increases DNA methylation at the NOS terminator of Pro35S:NPTII and at some endogenous genomic loci, which are also targeted by the demethylation enzyme REPRESSOR OF SILENCING 1 (ROS1). Furthermore, mutations in multifunctional protein 2 (MFP2) and 3-ketoacyl-CoA thiolase-2 (KAT2/PED1/PKT3), two enzymes in the last two steps of the ß-oxidation pathway, lead to similar patterns of DNA hypermethylation as in acx4 Thus, metabolites from fatty acid ß-oxidation in peroxisomes are closely linked to nuclear epigenetic modifications, which may affect diverse cellular processes in plants.

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