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1.
Stroke ; 55(1): 156-165, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38037225

RESUMO

BACKGROUND: Stroke survivors with impaired balance and motor function tend to have relatively poor functional outcomes. The cerebellum and primary motor cortex (M1) have been suggested as targets for neuromodulation of balance and motor recovery after stroke. This study aimed to compare the efficacy and safety of intermittent theta-burst stimulation (iTBS) to the cerebellum or M1 on balance and motor recovery in patients with stroke. METHODS: In this randomized, double-blind, sham-controlled clinical trial, patients with subacute stroke were randomly divided into 3 groups: M1-, cerebellar-, and sham-iTBS (n=12 per group; 15 sessions, 3 weeks). All outcomes were evaluated before intervention (T0), after 1 week of intervention (T1), after 3 weeks of intervention (T2), and at follow-up (T3). The primary outcome was the Berg balance scale score at T2. Secondary outcomes include the Fugl-Meyer assessment scale for lower extremities, the trunk impairment scale, the Barthel index, the modified Rankin Scale, the functional ambulation categories, and cortical excitability. RESULTS: A total of 167 inpatients were screened, 36 patients (age, 57.50±2.41 years; 10 women, 12 ischemic) were enrolled between December 2020 and January 2023. At T2, M1- or cerebellar-iTBS significantly improved Berg balance scale scores by 10.7 points ([95% CI, 2.7-18.6], P=0.009) and 14.2 points ([95% CI, 1.2-27.2], P=0.032) compared with the sham-iTBS group. Moreover, the cerebellar-iTBS group showed a significantly greater improvement in Fugl-Meyer assessment scale for lower extremities scores by 5.6 points than the M1-iTBS ([95% CI, 0.3-10.9], P=0.037) and by 7.8 points than the sham-iTBS ([95% CI, 1.1-14.5], P=0.021) groups at T2. The motor-evoked potential amplitudes of the M1- and cerebellar-iTBS groups were higher than those of the sham-iTBS group (P<0.001). CONCLUSIONS: Both M1- and cerebellar-iTBS could improve balance function. Moreover, cerebellar-iTBS, but not M1-iTBS, induced significant effects on motor recovery. Thus, cerebellar-iTBS may be a valuable new therapeutic option in stroke rehabilitation programs. REGISTRATION: URL: https://www.chictr.org.cn/; Unique identifier: ChiCTR2100047002.


Assuntos
Córtex Motor , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Humanos , Feminino , Pessoa de Meia-Idade , Estimulação Magnética Transcraniana , Cerebelo
2.
Fish Shellfish Immunol ; 148: 109476, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38447780

RESUMO

Trachinotus ovatus is an economically important fish and has been recommended as a high-quality aquaculture fish breed for the high-quality development of sea ranches in the South China Sea. However, T. ovatus shows intolerance to low temperature, greatly limiting the extension of farming scale, reducing production efficiency in winter, and increasing farming risks. In this study, liver transcriptome analysis was investigated in T. ovatus under acute low temperature conditions (20 and 15 °C) using RNA sequencing (RNA-Seq) technology. Inter-groups differential expression analysis and trend analysis screened 1219 DEGs and four significant profiles (profiles 0, 3, 4, and 7), respectively. GO enrichment analysis showed that these DEGs were mainly related to metabolic process and cell growth and death process. KEGG enrichment analysis found that DEGs were mainly associated with lipid metabolism, carbohydrate metabolism, and cell growth and death, such as gluconeogenesis, glycolysis, fatty acid oxidation, cholesterol biosynthesis, p53 signaling pathway, cell cycle arrest, and apoptotic cell death. Moreover, protein-protein interaction networks identified two hub genes (FOS and JUNB) and some important genes related to metabolic process and cell growth and death process, that corresponding to enrichment analysis. Overall, gluconeogenesis, lipid mobilization, and fatty acid oxidation in metabolic process and cell cycle arrest and apoptotic cell death in cell growth and death process were enhanced, while glycolysis, liver glycogen synthesis and cholesterol biosynthesis in metabolic process were inhibited. The enhancement or attenuatment of metabolic process and cell growth and death process is conducive to maintain energy balance, normal fluidity of cell membrane, normal physiological functions of liver cell, enhancing the tolerance of T. ovatus to cold stress. These results suggested that metabolic process and cell growth and death process play important roles in response to acute cold stress in the liver of T. ovatus. Gene expreesion level analysis showed that acute cold stress at 15 °C was identified as a critical temperature point for T. ovatus in term of cellular metabolism alteration and apoptosis inducement, and rewarming intervention should be timely implemented above 15 °C. Our study can provide theoretical support for breeding cold-tolerant cultivars of T. ovatus, which is contributed to high-quality productions fish production.


Assuntos
Resposta ao Choque Frio , Perfilação da Expressão Gênica , Animais , Resposta ao Choque Frio/genética , Perfilação da Expressão Gênica/veterinária , Peixes/genética , Fígado/metabolismo , Temperatura Baixa , Colesterol/metabolismo , Ácidos Graxos/metabolismo , Transcriptoma
3.
Int J Mol Sci ; 25(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38256129

RESUMO

Trachinotus ovatus is an economically important mariculture fish, and hypoxia has become a critical threat to this hypoxia-sensitive species. However, the molecular adaptation mechanism of T. ovatus liver to hypoxia remains unclear. In this study, we investigated the effects of acute hypoxic stress (1.5 ± 0.1 mg·L-1 for 6 h) and re-oxygenation (5.8 ± 0.3 mg·L-1 for 12 h) in T. ovatus liver at both the transcriptomic and metabolic levels to elucidate hypoxia adaptation mechanism. Integrated transcriptomics and metabolomics analyses identified 36 genes and seven metabolites as key molecules that were highly related to signal transduction, cell growth and death, carbohydrate metabolism, amino acid metabolism, and lipid metabolism, and all played key roles in hypoxia adaptation. Of these, the hub genes FOS and JUN were pivotal hypoxia adaptation biomarkers for regulating cell growth and death. During hypoxia, up-regulation of GADD45B and CDKN1A genes induced cell cycle arrest. Enhancing intrinsic and extrinsic pathways in combination with glutathione metabolism triggered apoptosis; meanwhile, anti-apoptosis mechanism was activated after hypoxia. Expression of genes related to glycolysis, gluconeogenesis, amino acid metabolism, fat mobilization, and fatty acid biosynthesis were up-regulated after acute hypoxic stress, promoting energy supply. After re-oxygenation for 12 h, continuous apoptosis favored cellular function and tissue repair. Shifting from anaerobic metabolism (glycolysis) during hypoxia to aerobic metabolism (fatty acid ß-oxidation and TCA cycle) after re-oxygenation was an important energy metabolism adaptation mechanism. Hypoxia 6 h was a critical period for metabolism alteration and cellular homeostasis, and re-oxygenation intervention should be implemented in a timely way. This study thoroughly examined the molecular response mechanism of T. ovatus under acute hypoxic stress, which contributes to the molecular breeding of hypoxia-tolerant cultivars.


Assuntos
Metabolismo Energético , Hipóxia , Animais , Hipóxia/genética , Perfilação da Expressão Gênica , Peixes , Homeostase , Aminoácidos , Ácidos Graxos
4.
Eur J Neurol ; 30(9): 2620-2628, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37203242

RESUMO

BACKGROUND AND PURPOSE: This study was undertaken to investigate the longitudinal impact of type 2 diabetes mellitus (T2DM) on the prodromal and dementia stages of Alzheimer disease (AD), focusing on diabetes duration and other comorbidities. METHODS: A total of 1395 dementia-free individuals aged 55-90 years with maximum 15-year follow-up data were enrolled from the Alzheimer's Disease Neuroimaging Initiative database. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) of the incidence of prodromal or dementia stages of AD. RESULTS: Longer T2DM duration (≥5 years; multiadjusted HR = 2.19, 95% confidence interval [CI] = 1.05-4.58), but not shorter T2DM duration (<5 years), was associated with a significantly increased risk of incident prodromal AD over a mean follow-up of 4.8 years. APOE ε4 allele (HR = 3.32, 95% CI = 1.41-7.79) and comorbid coronary artery disease (CAD; HR = 3.20, 95% CI = 1.29-7.95) further increased the risk of incident prodromal AD in patients with T2DM. No significant association was observed between T2DM and the risk of progression from prodromal AD to AD dementia. CONCLUSIONS: T2DM, which is characterized by a longer duration, increases the incidence risk of prodromal AD but not AD dementia. APOE ε4 allele and comorbid CAD strengthen the relationship between T2DM and prodromal AD. These findings highlight T2DM characteristics and its comorbidities as predictors for accurate prediction of AD and screening of at-risk populations.


Assuntos
Doença de Alzheimer , Diabetes Mellitus Tipo 2 , Humanos , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/genética , Doença de Alzheimer/complicações , Estudos Longitudinais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Apolipoproteína E4/genética , Genótipo , Fatores de Risco
5.
Mol Biol Rep ; 51(1): 40, 2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38158471

RESUMO

PURPOSE: PABPN1 acts as a modulator of poly(A) tail length and alternative polyadenylation. This research was aimed to explore the role of PABPN1 in colorectal cancer (CRC). METHODS: Public databases were performed to analyze expression, location, roles of prognosis and tumor immunity and interaction with RNAs and proteins of PABPN1. To investigate PABPN1 expression in tissues, 78 CRC specimens were collected to conduct IHC, and 30 pairs of frozen CRC and corresponding adjacent normal tissues were used to conduct qRT-PCR and WB. In addition, in vitro experiments were then carried out to identify the role of PABPN1 in CRC. RESULTS: Compared with normal tissues, PABPN1 expression was significant higher in CRC. Its high level predicted poor outcome of CRC. Th1 and Treg had significant negative relationships not only with PABPN1 expression, but also with six molecules interacting with PABPN1, including IFT172, KIAA0895L, RECQL4, WDR6, PABPC1 and NCBP1. In addition, PABPN1 had negative relationships with quite a few immune markers, such as CSF1R, IL-10, CCL2 and so on. In cellular experiments, silencing PABPN1 inhibited proliferation and promoted apoptosis in HCT-116 CRC cells. CONCLUSION: In summary, PABPN1 might become a novel biomarker and correlate with tumor immunity in CRC.


Assuntos
Neoplasias Colorretais , RNA , Humanos , RNA Mensageiro , Células HCT116 , Biomarcadores , Neoplasias Colorretais/metabolismo , Proliferação de Células/genética , Linhagem Celular Tumoral , Proteína I de Ligação a Poli(A) , Proteínas do Citoesqueleto/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
6.
J Exp Bot ; 73(13): 4306-4322, 2022 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-35437589

RESUMO

Bryophytes including mosses, liverworts, and hornworts are among the earliest land plants, and occupy a crucial phylogenetic position to aid in the understanding of plant terrestrialization. Despite their small size and simple structure, bryophytes are the second largest group of extant land plants. They live ubiquitously in various habitats and are highly diversified, with adaptive strategies to modern ecosystems on Earth. More and more genomes and transcriptomes have been assembled to address fundamental questions in plant biology. Here, we review recent advances in bryophytes associated with diversity, phylogeny, and ecological adaptation. Phylogenomic studies have provided increasing supports for the monophyly of bryophytes, with hornworts sister to the Setaphyta clade including liverworts and mosses. Further comparative genomic analyses revealed that multiple whole-genome duplications might have contributed to the species richness and morphological diversity in mosses. We highlight that the biological changes through gene gain or neofunctionalization that primarily evolved in bryophytes have facilitated the adaptation to early land environments; among the strategies to adapt to modern ecosystems in bryophytes, desiccation tolerance is the most remarkable. More genomic information for bryophytes would shed light on key mechanisms for the ecological success of these 'dwarfs' in the plant kingdom.


Assuntos
Briófitas , Embriófitas , Briófitas/genética , Ecossistema , Embriófitas/genética , Genômica , Filogenia , Plantas/genética , Transcriptoma
7.
Scand J Gastroenterol ; 57(5): 603-609, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34983263

RESUMO

BACKGROUND: Esophagogastroduodenoscopy (EGD) is fundamental for detecting upper gastrointestinal (GI) neoplasms. However, the impact of sedation on small neoplasm detection during EGD has not been evaluated. The aim of this study was to investigate whether EGD with sedation could improve small upper GI neoplasm detection. METHODS: This propensity score-matched retrospective study analyzed the medical records of outpatients undergoing diagnostic EGD at a large tertiary center between January 2013 and December 2018. The primary outcome was the detection rate of small upper GI neoplasms (≤10 mm). The secondary outcomes were biopsy rate and small neoplasms in different anatomic subsites. RESULTS: After propensity score matching, 20,052 patients undergoing diagnostic EGD with or without propofol sedation were identified. A higher detection rate of small upper GI neoplasms was observed in the sedation group (2.80% vs. 2.02%; p < .001). In particular, the detection rate of small cancers in the sedation group was 3-fold higher than that in the no-sedation group (0.16% vs. 0.05%; p = .023). Small neoplasms were more likely identified at the gastric antrum (1.60% vs. 1.09%; p = .002) and angulus (0.66% vs. 0.45%; p = .044) in the sedation group. In addition, endoscopists were more likely to take biopsies when performing sedated EGD (41.4% vs. 36.4%, p < .001), and a higher biopsy rate was associated with an increased detection rate of small neoplasms. CONCLUSIONS: Sedation was significantly associated with a higher detection rate of small upper GI neoplasms and might be recommended for improving the quality of EGD.


Assuntos
Anestesia , Neoplasias , Propofol , Sedação Consciente , Endoscopia do Sistema Digestório , Humanos , Pontuação de Propensão , Estudos Retrospectivos
8.
Langmuir ; 37(3): 1194-1205, 2021 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-33423497

RESUMO

Non-van der Waals (non-vdW) solids are emerging sources of two-dimensional (2D) nanosheets that can be produced via liquid-phase exfoliation (LPE), and are beginning to expand our understanding of 2D and quasi-2D materials. Recently, nanosheets formed by LPE processing of bulk metal diborides, a diverse family of layered non-vdW ceramic materials, have been reported. However, detailed knowledge of the exfoliation efficiency of these nanomaterials is lacking, and is important for their effective solution-phase processing and for understanding their fundamental surface chemistry, since they have significant differences from more conventional nanosheets produced from layered vdW compounds. Here in this paper we use Hansen solubility theory to investigate nanosheets of the metal borides CrB2 and MgB2 derived from LPE. By preparing dispersions in 33 different solvents, we determine Hansen solubility parameters (δD, δP, δH) for both these metal diborides. We find that they exhibit notably higher δP and δH values compared to conventional vdW materials such as graphene and MoS2, likely as a result of the types of bonds broken in such materials from exfoliation which allows for more favorable interactions with more polar and hydrogen-bonding solvents. We apply the solubility parameters to identify cosolvent blends suitable for CrB2 and MgB2 that produce dispersions with concentrations that match or exceed those of the top-performing individual solvents for each material and that have markedly higher stability compared to the constituent solvents of the blends alone. This work provides insight into the exfoliation effectiveness of different solvents for preparation of nanosheets from metal diborides and non-vdW materials in general. Such knowledge will be crucial for developing liquid-phase exfoliation strategies for incorporating these materials in applications such as nanocomposites, inks, and coatings.

9.
Cancer Cell Int ; 20: 141, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32368187

RESUMO

BACKGROUND: Without targets, triple negative breast cancer (TNBC) has the worst prognosis in all subtypes of breast cancer (BC). Recently, eukaryotic translation initiation factor 3 m (eIF3m) has been declared to be involved in the malignant progression of various neoplasms. The aim of this study is to explore biological functions of eIF3m in TNBC. METHODS: Multiple databases, including Oncomine, KM-plotter and so on, were performed to analyze prognosis and function of eIF3m in TNBC. After transfection of eIF3m-shRNA lentivirus, CCK-8, colony formation assay, cell cycle analysis, wound healing assay, transwell assays, mitochondrial membrane potential assay and cell apoptosis analysis were performed to explore the roles of eIF3m in TNBC cell bio-behaviors. In addition, western blotting was conducted to analyze the potential molecular mechanisms of eIF3m. RESULTS: In multiple databases, up-regulated eIF3m had lower overall survival, relapse-free survival and post progression survival in BC. EIF3m expression in TNBC was obviously higher than in non-TNBC or normal breast tissues. Its expression in TNBC was positively related to differentiation, lymph node invasion and distant metastasis. After knockdown of eIF3m, cell proliferation, migration, invasion and levels of mitochondrial membrane potential of MDA-MB-231 and MDA-MB-436 were all significantly suppressed, while apoptosis rates of them were obviously increased. In addition, eIF3m could regulate cell-cycle, epithelial-mesenchymal transition and apoptosis-related proteins. Combined with public databases and RT-qPCR, 14 genes were identified to be modulated by eIF3m in the development of TNBC. CONCLUSIONS: eIF3m is an unfavorable indicator of TNBC, and plays a vital role in the process of TNBC tumorigenesis.

10.
Chemistry ; 26(29): 6292-6295, 2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32432399

RESUMO

This Special Issue of Chemistry-A European Journal is dedicated to the Chemical Functionalization of 2D Materials, and features some great contributions from experts in the field of 2D materials. This issue was originally assembled to support the Symposium G "Chemical Functionalization of 2D Materials" at the European Materials Research Society (E-MRS) 2020 Spring Meeting, which was originally scheduled to be held in Strasbourg, France, from May 25th to 29th, 2020. Although the E-MRS 2020 Spring Meeting has been cancelled due to the COVID-19 outbreak, the publication of this Special Issue has proceeded and has become even more important as the contributors discuss diverse and timely research themes related to 2D materials. In this Editorial, a brief overview of the different types of 2D materials is given, together with the chemical functionalization schemes that can be applied to them to achieve new properties as well as enable improved performance in applications. Some of the articles featured in this Special Issue are also highlighted, with the hope that they will inspire readers and further advance the field.

11.
Langmuir ; 35(17): 5693-5701, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30950619

RESUMO

The two-dimensional transition-metal dichalcogenide molybdenum disulfide (MoS2) has been intensely studied in the past several years due to its exceptional electronic, optical, and chemical properties in a wide range of applications. The chemical functionalization of MoS2 allows its properties and interfacial interactions to be tuned and controlled. Recently, we reported the direct covalent functionalization of semiconducting MoS2 with aryl diazonium salts, without the use of harsh initial treatments or phase engineering. In this paper, we confirm and expand the covalent functionalization reaction model by performing a detailed study of the reaction kinetics for monolayer MoS2 functionalized by 4-nitrobenzene tetrafluoroborate (4-NBD). We find that both the Freundlich and Temkin isotherm models are good descriptors of the reaction due to the energetically inhomogeneous surface of MoS2 and the indirect adsorbate-adsorbate interactions from previously attached nitrophenyl groups, respectively. The reaction kinetics was then found to be well described using a pseudo-second-order model, showing that the order of this reaction is two. This study supports our previous work and gives us a deeper understanding of the nature of the covalent functionalization of MoS2.

12.
Future Oncol ; 14(22): 2279-2291, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29656661

RESUMO

AIM: This present study was aimed to compare the role of Oct4 in left-sided colon cancer (LCC) with right-sided colon cancer (RCC). PATIENTS & METHODS: One hundred and fifty one pathology specimens, 68 frozen-thawed tumors and cell lines were used to evaluate the role of Oct4 in LCC and RCC through immunohistochemistry, western blot and real-time quantitative PCR. RESULTS: In LCC, positive expression of Oct4 was positively related to differentiation and Dukes stage (p < 0.01). Only in RCC, Oct4 expression was also positively related to lymphatic invasion and survival rates of 'negative group' were significantly higher. CONCLUSION: In summary, Oct4 was related to tumor differentiation and later Dukes stage in colon cancer, and was correlated with invasion of lymphatic only in RCC. In addition, Oct4 was a potential prognostic indicator in RCC.


Assuntos
Neoplasias do Colo/mortalidade , Neoplasias do Colo/patologia , Fator 3 de Transcrição de Octâmero/metabolismo , Idoso , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Neoplasias do Colo/metabolismo , Neoplasias do Colo/cirurgia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Fator 3 de Transcrição de Octâmero/genética , Prognóstico
13.
Proc Natl Acad Sci U S A ; 112(16): 5225-30, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25847999

RESUMO

Alzheimer's disease (AD) is one of most devastating diseases affecting elderly people. Amyloid-ß (Aß) accumulation and the downstream pathological events such as oxidative stress play critical roles in pathogenesis of AD. Lessons from failures of current clinical trials suggest that targeting multiple key pathways of the AD pathogenesis is necessary to halt the disease progression. Here we show that Edaravone, a free radical scavenger that is marketed for acute ischemic stroke, has a potent capacity of inhibiting Aß aggregation and attenuating Aß-induced oxidation in vitro. When given before or after the onset of Aß deposition via i.p. injection, Edaravone substantially reduces Aß deposition, alleviates oxidative stress, attenuates the downstream pathologies including Tau hyperphosphorylation, glial activation, neuroinflammation, neuronal loss, synaptic dysfunction, and rescues the behavioral deficits of APPswe/PS1 mice. Oral administration of Edaravone also ameliorates the AD-like pathologies and memory deficits of the mice. These findings suggest that Edaravone holds a promise as a therapeutic agent for AD by targeting multiple key pathways of the disease pathogenesis.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Antipirina/análogos & derivados , Transtornos Cognitivos/tratamento farmacológico , Administração Oral , Doença de Alzheimer/complicações , Doença de Alzheimer/patologia , Amiloide/metabolismo , Peptídeos beta-Amiloides/toxicidade , Animais , Antipirina/administração & dosagem , Antipirina/química , Antipirina/farmacologia , Antipirina/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Linhagem Celular , Transtornos Cognitivos/complicações , Transtornos Cognitivos/patologia , Dendritos/efeitos dos fármacos , Dendritos/patologia , Edaravone , Humanos , Inflamação/patologia , Camundongos Transgênicos , Neurotoxinas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Presenilina-1/metabolismo , Agregação Patológica de Proteínas/complicações , Agregação Patológica de Proteínas/tratamento farmacológico , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas tau/metabolismo
14.
Chem Soc Rev ; 46(15): 4530-4571, 2017 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-28621376

RESUMO

The participation of graphene in electron transfer chemistry, where an electron is transferred between graphene and other species, encompasses many important processes that have shown versatility and potential for use in important applications. Examples of these processes range from covalent functionalization of graphene to modify its properties and incorporate different functional groups, to electrochemical reactions and selective etching. In this paper, we review recent developments in these areas of the electron transfer chemistry of graphene. We address recent progress on controlling covalent functionalization through chemical and physical methods, and how carefully functionalized graphene can be incorporated into composite materials with enhanced properties. We review the selective etching of graphene to form edges and nanopores, which have unique chemical and physical properties. Nanoporous graphene is promising for new membrane and filtration applications. We also discuss the electrochemistry of graphene grown by chemical vapour deposition in two-dimensional and three-dimensional geometries, which enables large surface areas and control over the distribution and concentration of edge and basal plane sites. We discuss the potential for each of these areas to have an impact in future applications such as filtration membranes, electronic devices, electrochemical electrodes, composite materials, and chemical sensors.

15.
J Asian Nat Prod Res ; 19(6): 581-594, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28376654

RESUMO

The scorpion peptide BmK AngM1 was reported to exhibit evident analgesic effect, but its yield by extraction from scorpion venom limits the research and application. The heterologous expression of BmK AngM1 was achieved in Pichia pastoris in our previous study. In order to realize high-level expression of recombinant BmK AngM1 (rBmK AngM1), the gene dosage of BmK AngM1 was optimized in engineered strains. The yield of rBmK AngM1 in the four-copy strain reached up to 100 mg/L, which was further enhanced to 190 mg/L by co-expressing with chaperones of PDI, BiP, and HAC1. Moreover, the yield of rBmK AngM1 was up to 1200 mg/L by high-density fermentation in 10 L fermenter. Finally, 360 mg rBmK AngM1 was purified from 1 L cultures by a two-step purification method. The efficient and convenient techniques presented in this study could facilitate further scale-up for industrial production of rBmK AngM1.


Assuntos
Pichia/química , Venenos de Escorpião/farmacologia , Fermentação , Dosagem de Genes , Chaperonas Moleculares/metabolismo , Estrutura Molecular , Proteínas Recombinantes/metabolismo
16.
Nano Lett ; 16(6): 3571-7, 2016 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-27120519

RESUMO

In the pursuit of two-dimensional (2D) materials beyond graphene, enormous advances have been made in exploring the exciting and useful properties of transition metal dichalcogenides (TMDCs), such as a permanent band gap in the visible range and the transition from indirect to direct band gap due to 2D quantum confinement, and their potential for a wide range of device applications. In particular, recent success in the synthesis of seamless monolayer lateral heterostructures of different TMDCs via chemical vapor deposition methods has provided an effective solution to producing an in-plane p-n junction, which is a critical component in electronic and optoelectronic device applications. However, spatial variation of the electronic and optoelectonic properties of the synthesized heterojunction crystals throughout the homogeneous as well as the lateral junction region and the charge carrier transport behavior at their nanoscale junctions with metals remain unaddressed. In this work, we use photocurrent spectral atomic force microscopy to image the current and photocurrent generated between a biased PtIr tip and a monolayer WSe2-MoS2 lateral heterostructure. Current measurements in the dark in both forward and reverse bias reveal an opposite characteristic diode behavior for WSe2 and MoS2, owing to the formation of a Schottky barrier of dissimilar properties. Notably, by changing the polarity and magnitude of the tip voltage applied, pixels that show the photoresponse of the heterostructure are observed to be selectively switched on and off, allowing for the realization of a hyper-resolution array of the switchable photodiode pixels. This experimental approach has significant implications toward the development of novel optoelectronic technologies for regioselective photodetection and imaging at nanoscale resolutions. Comparative 2D Fourier analysis of physical height and current images shows high spatial frequency variations in substrate/MoS2 (or WSe2) contact that exceed the frequencies imposed by the underlying substrates. These results should provide important insights in the design and understanding of electronic and optoelectronic devices based on quantum confined atomically thin 2D lateral heterostructures.

17.
J Neurochem ; 138(1): 163-73, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26991827

RESUMO

The neurotrophin receptor p75 (p75NTR) is a receptor for amyloid-beta (Aß) and mediates Aß-induced neurodegenerative signals. The ectodomain of p75NTR (p75ECD) is a physiological protective factor against Aß in Alzheimer's disease (AD). We have previously demonstrated that the shedding of p75ECD from the cell surface is down-regulated in AD brains and restoration of the p75ECD level in the brain, through intracranial administration of p75ECD by adeno-associated virus vectors, attenuates AD-like pathologies in an AD mouse model. In this study, we further investigated the feasibility and efficacy of peripheral administration of AAV-p75ECD on brain amyloid burden and associated pathogenesis. We found that intramuscular delivery of AAV-p75ECD increased the level of p75ECD in the blood, significantly improved the behavioral phenotype of amyloid precursor protein/PS1 transgenic mice, and reduced brain amyloid burden, attenuated Tau hyperphosphorylation, and neuroinflammation. Furthermore, intramuscular delivery of AAV-p75ECD was well tolerated. Our results indicate that peripheral delivery of p75ECD represents a safe and effective therapeutic strategy for AD. The ectodomain of p75NTR (p75ECD) is a physiological protective factor against amyloid-beta (Aß) in Alzheimer's disease (AD). Intramuscular delivery of AAV-p75ECD increased the p75ECD levels in the blood, reduced brain amyloid burden through a 'peripheral sink' mechanism and alleviates AD-type pathologies. Peripheral delivery of p75ECD represents a promising therapeutic strategy for AD.


Assuntos
Doença de Alzheimer/patologia , Doença de Alzheimer/terapia , Transtornos Cognitivos/terapia , Receptor de Fator de Crescimento Neural/química , Receptor de Fator de Crescimento Neural/metabolismo , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Transtornos Cognitivos/genética , Dependovirus/genética , Modelos Animais de Doenças , Vetores Genéticos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Injeções Intramusculares , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Presenilina-1/genética , Receptor de Fator de Crescimento Neural/genética , Transdução Genética
18.
Yao Xue Xue Bao ; 50(7): 910-5, 2015 Jul.
Artigo em Zh | MEDLINE | ID: mdl-26552156

RESUMO

BmK AngM1 is a long-chain scorpion toxin purified from the venom of Buthus martensii Karsch. It has been reported to exhibit evident analgesic effect and low toxicity, and has the potential to be a novel analgesic drug. The BmKAngM1 gene was transformed into Pichiapastoris GS115. Mut+ and Mut(s) recombinant strains were screened by phenotype and Mut+ recombinant strains were used to detect BmK AngMl gene copy number in the real-time PCR. Expression of BmK AngM1 in the Mut+ recombinant strain was compared with that of the Mut(s) recombinant strain with the same single copy of BmK AngM1 gene under the same condition. The results indicated that the transcription level of BmK AngM1 gene in the Mut(s) recombinant strain was 2.7 fold of that in the Mut recombinant strain in the real-time PCR, and the expression of BmK AngM 1 in the Mut(s) recombinant strain was 1.5 fold of that in the Mut+ recombinant strain. Therefore, Mut(s) recombinant strain showed better ability to express BmK AngM1 than Mut+ recombinant strain.


Assuntos
Proteínas de Artrópodes/biossíntese , Pichia/metabolismo , Proteínas Recombinantes/biossíntese , Venenos de Escorpião/química , Animais , Dosagem de Genes
19.
Yao Xue Xue Bao ; 50(2): 148-53, 2015 Feb.
Artigo em Zh | MEDLINE | ID: mdl-25975020

RESUMO

Traditional herbal medicines, Panax ginseng, Panax quinquefolium and Panax notoginseng, attract our attention for their extensive and powerful pharmacological activities. Ginsenosides are the main active constituents of these medicinal herbs. The related glycosyltransferases involved in ginsenoside biosynthesis are the key enzymes which catalyze the last important step. Modification of ginsenoside aglycones by glycosyltransferases produces the complexity and diversity of ginsenosides, which have more extensive pharmacological activity. At present, ginsenoside aglycones and compound K have been obtained by synthetic biology. As the last step of ginsenoside biosynthesis, glycosylation of ginsenoside aglycones has been studied intensively in recent years. This review summarizes the basic strategies and research advances in studies on glycosyltransferases involved in ginsenoside biosynthesis, which is expected to lay the theoretical foundation for the in-depth research of biosynthetic pathway of ginsenosides and their production by synthetic biology.


Assuntos
Ginsenosídeos/biossíntese , Glicosiltransferases/metabolismo , Vias Biossintéticas , Panax/química , Plantas Medicinais/química , Biologia Sintética
20.
Yao Xue Xue Bao ; 50(1): 118-22, 2015 Jan.
Artigo em Zh | MEDLINE | ID: mdl-25924486

RESUMO

The cyclization of 2,3-oxidosqualene is the key branch point of ergosterol and triterpenoid biosynthesis. Downregulation of 2,3-oxidosqualene metabolic flux to ergosterol in Saccharomyces cerevisiae may redirect the metabolic flux toward the triterpenoid synthetic pathway. In our study, primers were designed according to erg7 gene sequence of S. cerevisiae. Three fragments including 5' long fragment, 5' short fragment and erg7 coding region fragment were amplified by PCR. 5' long fragment consists of the promoter and a part of erg7 coding region sequence. 5' short fragment consists of a part of promoter and a part of erg7 coding region sequence. These fragments were inserted reversely into pESC-URA to construct antisense expression plasmids. The recombinant plasmids were transformed into S. cerevisiae INVSc1 and recombinant strains were screened on the nutritional deficient medium SD-URA. The erg7 expression level of recombinant strains, which harbored antisense expression plasmid of erg7 coding region, was similar to that of INVScl by semi-quantitative PCR detection. But erg7 expression level of recombinant strains, which harbored 5' long antisense fragment and 5' short antisense fragment, was significantly lower than that of the control. The results of TLC and HPLC showed that the ergosterol content of recombinant strains, which harbored 5' long antisense fragment, decreased obviously. The ergosterol contents of the others were almost equal to that of INVSc1. Lanosterol synthase gene expression was downregulated by antisense RNA technology in S. cerevisiae, which lays a foundation for reconstructing triterpenoid metabolic pathway in S. cerevisiae by synthetic biology technology.


Assuntos
Transferases Intramoleculares/metabolismo , RNA Antissenso , Saccharomyces cerevisiae/genética , Esqualeno/análogos & derivados , Primers do DNA , Regulação para Baixo , Expressão Gênica , Transferases Intramoleculares/genética , Plasmídeos , Reação em Cadeia da Polimerase , Saccharomyces cerevisiae/enzimologia , Esqualeno/metabolismo , Transformação Genética
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