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1.
Cell Biol Int ; 47(7): 1170-1182, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37269228

RESUMO

Paclitaxel (PTX) is an effective chemotherapeutic agent for cancer patients. It has been reported that circular RNA (circRNA) circ_0005785is involved in the progression of hepatocellular carcinoma (HCC). The purpose of this study is to explore the role and mechanism of circ_0005785 in the PTX resistance of HCC. Cell viability, proliferation, invasion, migration, apoptosis, and angiogenesis were detected using 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT), colony formation, transwell, wound-healing, flow cytometry, and tube formation assay. Circ_0005785, microRNA-640 (miR-640), and Glycogen synthase kinase-3 beta (GSK3ß) levels were detected using real-time quantitative polymerase chain reaction. Protein levels of Proliferating cell nuclear antigen (PCNA), Bcl-2, and GSK3ß were measured using western blot assay. After being predicted using Circular RNA interactome or TargetScan, binding between miR-640 and circ_0005785 or GSK3ß was verified using dual-luciferase reporter and RNA Immunoprecipitation assay. PTX treatment could repress HCC cell viability, decrease circ_0005785 and GSK3ß expression, and increase the miR-640 level in HCC cell lines. Furthermore, circ_0005785 and GSK3ß were increased, and miR-640 was decreased in HCC tissues and cell lines. Moreover, circ_0005785 knockdown hindered proliferation, migration, invasion, angiogenesis, and boosted apoptosis in PTX-treated HCC cells in vitro. In addition, circ_0005785 silencing improved the PTX sensitivity of HCC in vivo. Mechanistically, circ_0005785 acted as a sponge of miR-640 to regulate GSK3ß expression. PTX restrained HCC tumorigenesis partly via regulating the circ_0005785/miR-640/GSK3ß axis, hinting at a promising therapeutic target for the HCC treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/genética , Glicogênio Sintase Quinase 3 beta/genética , RNA Circular/genética , Neoplasias Hepáticas/genética , Carcinogênese/genética , Transformação Celular Neoplásica , MicroRNAs/genética , Proliferação de Células , Linhagem Celular Tumoral
2.
Dev Med Child Neurol ; 65(4): 534-543, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36175372

RESUMO

AIM: To explore the phenotypic spectrum and refine the genotype-phenotype correlation of DYNC1H1-related epilepsy. METHOD: The clinical data of 15 patients with epilepsy in our cohort and 50 patients with epilepsy from 24 published studies with the DYNC1H1 variants were evaluated. RESULTS: In our cohort, 13 variants were identified from 15 patients (seven males, eight females). Twelve variants were de novo and seven were new. Age at seizure onset ranged from 3 months to 4 years 5 months (median age 1 year). Common seizure types were epileptic spasms, focal seizures, tonic seizures, and myoclonic seizures. Mild-to-severe developmental delay was present in all patients. Six patients were diagnosed with West syndrome and one was diagnosed with epileptic encephalopathy with continuous spikes and waves during slow sleep (CSWS). Collectively, in our cohort and published studies, 17% had ophthalmic diseases, 31% of variants were located in the stalk domain, and 92% patients with epilepsy had a malformation of cortical development (MCD). INTERPRETATION: The phenotypes of DYNC1H1-related epilepsy included multiple seizure types; the most common epileptic syndrome was West syndrome. CSWS is a new phenotype of DYNC1H1-related epilepsy. One-third of the variants in patients with epilepsy were located in the stalk domain. Most patients had a MCD and developmental delay. WHAT THIS PAPER ADDS: Nearly 40% of patients with DYNC1H1 variants had epilepsy. Ninety-two percent of patients with DYNC1H1-related epilepsy had malformation of cortical development. More than 10% of patients with DYNC1H1-related epilepsy were diagnosed with West syndrome. Continuous spikes and waves during slow sleep could be a new phenotype of DYNC1H1 variants. One-third of the variants in patients with epilepsy were located in the stalk domain.


Assuntos
Epilepsia , Espasmos Infantis , Masculino , Feminino , Humanos , Espasmos Infantis/genética , Mutação , Epilepsia/genética , Convulsões/genética , Estudos de Associação Genética , Eletroencefalografia , Dineínas do Citoplasma/genética
3.
Dev Med Child Neurol ; 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37960945

RESUMO

AIM: To investigate the seizure course of PCDH19 clustering epilepsy (PCDH19-CE) in a cohort of female children in China. METHOD: This ambidirectional cohort study examined 113 female patients with PCDH19-CE through multicentre collaboration. Prognostic factors for seizure freedom were evaluated by multivariate Cox regression analysis. RESULTS: The median seizure course period from seizure onset was 6 years 6 months. Of 113 patients, 78% and 56% experienced seizure freedom for at least 1 year and at least 2 years respectively. In patients younger than 5 years (n = 30), 5 to 10 years (n = 52), and older than 10 years (n = 31), 57%, 81%, and 94% experienced at least 1 year of seizure freedom, and 32%, 52%, and 84% experienced at least 2 years of seizure freedom, respectively. However, 58% (65 out of 113) relapsed at least once after more than 1 year of seizure freedom without trigger exposure (40%) or because of common triggers, including fever (43%) and antiseizure medication (ASM) reduction (29%). There was an 84% risk of seizure relapse after ASM reduction attempts. The likelihood of seizure freedom decreased with early age at seizure onset and developmental delay. INTERPRETATION: Patients with PCDH19-CE exhibit increasing seizure freedom with age, but there is a risk of relapse. ASM reduction in children younger than 10 years old requires caution. Patients with early seizure onset and developmental delay have a reduced chance of seizure freedom.

4.
Dev Med Child Neurol ; 64(1): 105-111, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34263451

RESUMO

AIM: To explore the genotypes and phenotypes of CACNA1A variants in children with epilepsy. METHOD: Eighteen children (six males, 12 females) with CACNA1A variants were identified using next-generation sequencing. RESULTS: There were 14 missense variants, two nonsense variants, one frameshift variant, and one splice site variant. Sixteen variants were de novo. Age at seizure onset ranged from 1 day to 8 years; median age was 8 months. Multiple seizure types were observed, including focal, generalized tonic-clonic, myoclonic, and absence seizures, as well as epileptic spasms and tonic seizures. Focal motor status epilepticus occurred in 10 individuals and generalized motor status epilepticus occurred in two individuals. All 18 children showed developmental delay. Focal motor status epilepticus resulted in cerebral atrophy in five individuals, mainly on the contralateral side. Interictal electroencephalogram showed focal discharges in 12 individuals, whereas five individuals had generalized discharges. Three individuals were seizure-free, whereas 15 still had seizures and five had recurrent status epilepticus at last follow-up. INTERPRETATION: Most children with epilepsy and CACNA1A variants had early seizure onset and developmental delay. Focal seizure was the most common seizure type. Most patients experienced status epilepticus. Unilateral cerebral atrophy could occur after focal motor status epilepticus. Patients with CACNA1A variants located in the transmembrane region may be at high risk of status epilepticus.


Assuntos
Canais de Cálcio/genética , Epilepsia/genética , Mutação , Convulsões/genética , Criança , Feminino , Estudos de Associação Genética , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Lactente , Recém-Nascido , Masculino , Fenótipo
5.
Lasers Med Sci ; 36(9): 1873-1881, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33392781

RESUMO

We aimed to investigate the mechanism and effect of photodynamic treatment mediated by 5-aminoketovalerate (5-ALA-PDT) on human ovarian cancer cells (OVCAR3 cells) and to provide a theoretical basis for the subsequent experimental step in vivo. Human ovarian cancer OVCAR3 cells were randomly divided into four groups: control group, laser irradiation alone group, photosensitizer alone group, and photodynamic treatment group. Alterations in cell morphology were observed with an inverted light microscope; cell viability was examined by CCK-8 assays. The ROS content and apoptosis rate were examined by flow cytometry analysis. Western blot was used to detect the expression of apoptosis-related proteins, such as caspase-3, Bax, and Bcl-2, and the expression of cleaved caspase-3 in live cells was detected by a cleaved caspase-3 assay kit. Inverted light microscopy showed alterations in cell morphology in different stages. Comparison with the three other groups indicated that tumor cell proliferation was significantly decreased in the photodynamic treatment group (P < 0.05). Flow cytometry analysis revealed that the content of ROS was higher in the photodynamic group than in the other three groups, and the apoptosis rate was higher in the photodynamic treatment group. The difference compared with the other three groups was statistically significant (P < 0.001). The western blot results indicated that the protein expression of Bcl-2 and caspase-3 was decreased in the photodynamic treatment group, and the protein expression level of Bax was increased (P < 0.05). The expression of cleaved caspase-3 was increased in the photodynamic treatment group compared with the other groups according to the data obtained with a microplate reader. Thus, our results demonstrated that the apoptosis and viability of OVCAR3 cells are altered in response to 5-ALA-PDT; however, no remarkable effects were observed in ovarian cancer cells treated with laser irradiation or photosensitizer alone. 5-ALA-PDT can significantly inhibit the growth of human ovarian cancer cells, and the mechanism of this effect is related to the tumor cell apoptosis mediated by the downregulation of Bcl-2 and caspase-3 and upregulation of Bax protein expression.


Assuntos
Neoplasias Ovarianas , Fotoquimioterapia , Apoptose , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico
6.
J Magn Reson Imaging ; 47(6): 1572-1577, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29236342

RESUMO

BACKGROUND: Previous studies indicated that two-dimensional-susceptibility weighted imaging (2D-SWI) could serve as a useful biomarker for differentiating the grade of liver fibrosis. PURPOSE: To evaluate the feasibility of 2D-SWI in the dynamic quantification of renal fibrosis in a rabbit model. STUDY TYPE: Longitudinal study. ANIMAL MODEL: Twenty-Four New Zealand White Rabbits including control group (n = 4); and renal fibrosis group (n = 20), by means of a unilateral ureteral obstruction (UUO) model. FIELD STRENGTH/SEQUENCE: The 3.0 T SWI using a 2D gradient-echo sequence. ASSESSMENT: The relative SWI signal ratio(r) of cortical and medulla (r = SIrenal /SImuscle ) was longitudinally assessed before ligation and on weeks 2, 4, 6, and 8 following ligation. Sirius Red staining was used to assess the degree of fibrosis in five high-power fields. STATISTICAL TESTS: The repeated measures of analysis of variance and linear regression analysis. RESULTS: Both the cortical and medullary r values were significantly higher in the UUO kidneys at week 2 compared with the kidneys before ligation. Over the course of UUO progression, significant changes occurred in the cortical and medullary r values in vivo and fibrosis scores in vitro (all P values < 0.05). The r values gradually decreased, while the fibrosis scores gradually increased over 8 weeks following ligation. The linear regression analysis showed a strong and significant correlation between cortical and medullary r values and the pathologic fibrosis scores (R2 = 0.91, 0.81, respectively). DATA CONCLUSION: The SWI sequence could provide a quantitative evaluation of renal fibrosis during UUO progression. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018;47:1572-1577.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Nefropatias/diagnóstico por imagem , Rim/diagnóstico por imagem , Imageamento por Ressonância Magnética , Ureter/diagnóstico por imagem , Obstrução Ureteral/patologia , Animais , Artefatos , Modelos Animais de Doenças , Progressão da Doença , Fibrose , Rim/patologia , Nefropatias/patologia , Modelos Lineares , Estudos Longitudinais , Masculino , Coelhos , Ureter/patologia
7.
Dev Med Child Neurol ; 60(6): 566-573, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29573403

RESUMO

AIM: To analyze the clinical outcome and neuroimaging over a long duration follow-up in the currently largest series of acute encephalopathy after status epilepticus in patients with Dravet syndrome. METHOD: Clinical and neuroimaging data of patients with Dravet syndrome with a history of acute encephalopathy (coma >24h) after status epilepticus from February 2005 to December 2016 at Peking University First Hospital were reviewed retrospectively. RESULTS: Thirty-five patients (15 males, 20 females) with a history of acute encephalopathy were enrolled from a total of 624 patients with Dravet syndrome (5.6%). The median onset age of acute encephalopathy was 3 years 1 month. The duration of status epilepticus varied between 40 minutes to 12 hours. Thirty-four patients had a high fever when status epilepticus occurred, and only one had a normal temperature. Coma lasted from 2 to 20 days. Twelve patients died and 23 survived with massive neurological regression. The median follow-up time was 2 years 1 month. Neuroimaging of 20 out of 23 survivors during the recovery phase showed diverse degrees of cortical atrophy with or without subcortical lesions. INTERPRETATION: Acute encephalopathy after status epilepticus is more prone to occur in patients with Dravet syndrome who had a high fever. The mortality rate is high in severe cases. Survivors are left with severe neurological sequelae but often with either no seizure or low seizure frequency. WHAT THIS PAPER ADDS: Acute encephalopathy is more prone to occur in patients with Dravet syndrome with a high fever. The mortality rate is high for acute encephalopathy after status epilepticus in patients with Dravet syndrome. Survivors have neurological sequelae.


Assuntos
Encefalopatias/diagnóstico por imagem , Encefalopatias/etiologia , Epilepsias Mioclônicas/complicações , Estado Epiléptico , Idade de Início , Criança , Pré-Escolar , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Lactente , Imageamento por Ressonância Magnética , Masculino , Estado Epiléptico/complicações , Estado Epiléptico/diagnóstico por imagem , Estado Epiléptico/etiologia
8.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 34(6): 787-791, 2017 Dec 10.
Artigo em Zh | MEDLINE | ID: mdl-29188601

RESUMO

OBJECTIVE: To determine the type and frequency of SCN1A deletions and duplications among patients with Dravet syndrome (DS). METHODS: For DS patients in which no mutations of the SCN1A gene were detected by PCR-DNA sequencing, SCN1A deletions and duplications were detected by multiplex ligation-dependent probe amplification (MLPA). RESULTS: In 680 DS patients, 489 had SCN1A mutations identified by PCR-DNA sequencing. In 191 patients who were negative for the SCN1A PCR-DNA sequencing, 15 (15/191, 7.9%) were detected with heterozygous SCN1A deletions or duplications, which included 14 (14/15, 93.3%) SCN1A deletions and 1 SCN1A duplication. There were 13 types of mutations, including whole SCN1A deletions in 3 patients, partial SCN1A deletions in 11 patients and partial SCN1A duplications in one patient. By testing the parents, 14 mutations were found to be de novo. For the remaining case, no SCN1A deletion or duplication was found in the mother, while the father was not available. CONCLUSION: Approximately 8% of Chinese patients who were negative for SCN1A mutation by PCR-sequencing have SCN1A deletions or duplications. The MLPA analysis should be considered as an important strategy for such patients. SCN1A deletions are more common than SCN1A duplications among DS patients, and the most common types are whole SCN1A deletions. The majority of SCN1A deletions or duplications are de novo.


Assuntos
Deleção de Genes , Duplicação Gênica , Canal de Sódio Disparado por Voltagem NAV1.1/genética , Epilepsias Mioclônicas/genética , Feminino , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase Multiplex
9.
J Am Chem Soc ; 138(1): 40-3, 2016 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-26675065

RESUMO

Encapsulation of sulfur in HiPCO-SWNTs leads to large changes in the Raman spectra with the appearance of new peaks at 319, 395, and 715 cm(-1) which originate from the sulfur species within the SWNTs, while the high frequency SWNT bands (ν > 1200 cm(-1)) are decreased in intensity. The encapsulated species also shifts the near-IR interband electronic transitions to lower energy by more than 10%. These effects seem to originate with the van der Waals interaction of the confined sulfur species with the walls of the SWNTs which are not expected to be significant in the case of the previously studied large diameter SWNTs. We suggest that sulfur in the small diameter SWNTs exists as a helical polymeric sulfur chain that enters the SWNT interior in the form of S2 ((3)Σ(g)(-)) molecules which undergo polymerization to linear diradicals.

10.
Acc Chem Res ; 48(8): 2270-9, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-26244611

RESUMO

Single-walled carbon nanotube (SWNT) thin films provide a unique platform for the development of electronic and photonic devices because they combine the advantages of the outstanding physical properties of individual SWNTs with the capabilities of large area thin film manufacturing and patterning technologies. Flexible SWNT thin film based field-effect transistors, sensors, detectors, photovoltaic cells, and light emitting diodes have been already demonstrated, and SWNT thin film transparent, conductive coatings for large area displays and smart windows are under development. While chirally pure SWNTs are not yet commercially available, the marketing of semiconducting (SC) and metallic (MT) SWNTs has facilitated progress toward applications by making available materials of consistent electronic structure. Nevertheless the electrical transport properties of networks of separated SWNTs are inferior to those of individual SWNTs. In particular, for semiconducting SWNTs, which are the subject of this Account, the electrical transport drastically differs from the behavior of traditional semiconductors: for example, the bandgap of germanium (E = 0.66 eV) roughly matches that of individual SC-SWNTs of diameter 1.5 nm, but in the range 300-100 K, the intrinsic carrier concentration in Ge decreases by more than 10 orders of magnitude while the conductivity of a typical SC-SWNT network decreases by less than a factor of 4. Clearly this weak modulation of the conductivity hinders the application of SC-SWNT films as field effect transistors and photodetectors, and it is the purpose of this Account to analyze the mechanism of the electrical transport leading to the unusually weak temperature dependence of the electrical conductivity of such networks. Extrinsic factors such as the contribution of residual amounts of MT-SWNTs arising from incomplete separation and doping of SWNTs are evaluated. However, the observed temperature dependence of the conductivity indicates the presence of midgap electronic states in the semiconducting SWNTs, which provide a source of low-energy excitations, which can contribute to hopping conductance along the nanotubes following fluctuation induced tunneling across the internanotube junctions, which together dominate the low temperature transport and limit the resistivity of the films. At high temperatures, the intrinsic carriers thermally activated across the bandgap as in a traditional semiconductor became available for band transport. The midgap states pin the Fermi level to the middle of the bandgap, and their origin is ascribed to defects in the SWNT walls. The presence of such midgap states has been reported in connection with scanning tunneling spectroscopy experiments, Coulomb blockade observations in low temperature electrical measurements, selective electrochemical deposition imaging, tip-enhanced Raman spectroscopy, high resolution photocurrent spectroscopy, and the modeling of the electronic density of states associated with various defects. Midgap states are present in conventional semiconductors, but what is unusual in the present context is the extent of their contribution to the electrical transport in networks of semiconducting SWNTs. In this Account, we sharpen the focus on the midgap states in SC-SWNTs, their effect on the electronic properties of SC-SWNT networks, and the importance of these effects on efforts to develop electronic and photonic applications of SC-SWNTs.

11.
Int J Mol Sci ; 17(10)2016 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-27706065

RESUMO

Degradation of rice straw by cooperative microbial activities is at present the most attractive alternative to fuels and provides a basis for biomass conversion. The use of microbial consortia in the biodegradation of lignocelluloses could reduce problems such as incomplete synergistic enzymes, end-product inhibition, and so on. In this study, a cellulolytic microbial consortium was enriched from the hindgut of Holotrichia parallela larvae via continuous subcultivation (20 subcultures in total) under static conditions. The degradation ratio for rice straw was about 83.1% after three days of cultivation, indicating its strong cellulolytic activity. The diversity analysis results showed that the bacterial diversity and richness decreased during the consortium enrichment process, and the consortium enrichment process could lead to a significant enrichment of phyla Proteobacteria and Spirochaetes, classes Clostridia, Epsilonproteobacteria, and Betaproteobacteria, and genera Arcobacter, Treponema, Comamonas, and Clostridium. Some of these are well known as typical cellulolytic and hemicellulolytic microorganisms. Our results revealed that the microbial consortium identified herein is a potential candidate for use in the degradation of waste lignocellulosic biomass and further highlights the hindgut of the larvae as a reservoir of extensive and specific cellulolytic and hemicellulolytic microbes.


Assuntos
Besouros/microbiologia , Lignina/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Bacteroidetes/enzimologia , Bacteroidetes/genética , Biomassa , Celulase/metabolismo , Besouros/crescimento & desenvolvimento , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Bacteriano/metabolismo , Firmicutes/enzimologia , Firmicutes/genética , Larva/microbiologia , Consórcios Microbianos , Análise de Componente Principal , Proteobactérias/enzimologia , Proteobactérias/genética , Análise de Sequência de DNA
12.
Nano Lett ; 14(7): 3930-7, 2014 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-24893323

RESUMO

The formation of covalent bonds to single-walled carbon nanotube (SWNT) or graphene surfaces usually leads to a decrease in the electrical conductivity and mobility as a result of the structural rehybridization of the functionalized carbon atoms from sp(2) to sp(3). In the present study, we explore the effect of metal deposition on semiconducting (SC-) and metallic (MT-) SWNT thin films in the vicinity of the percolation threshold and we are able to clearly delineate the effects of weak physisorption, ionic chemisorption with charge transfer, and covalent hexahapto (η(6)) chemisorption on these percolating networks. The results support the idea that for those metals capable of forming bis-hexahapto-bonds, the generation of covalent (η(6)-SWNT)M(η(6)-SWNT) interconnects provides a conducting pathway in the SWNT films and establishes the transition metal bis-hexahapto organometallic bond as an electronically conjugating linkage between graphene surfaces.

13.
Acc Chem Res ; 46(1): 65-76, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23116475

RESUMO

In this Account, we discuss the chemistry of graphitic materials with particular reference to three reactions studied by our research group: (1) aryl radical addition, from diazonium precursors, (2) Diels-Alder pericyclic reactions, and (3) organometallic complexation with transition metals. We provide a unified treatment of these reactions in terms of the degenerate valence and conduction bands of graphene at the Dirac point and the relationship of their orbital coefficients to the HOMO and LUMO of benzene and to the Clar structures of graphene. In the case of the aryl radical addition and the Diels-Alder reactions, there is full rehybridization of the derivatized carbon atoms in graphene from sp(2) to sp(3), which removes these carbon atoms from conjugation and from the electronic band structure of graphene (referred to as destructive rehybridization). The radical addition process requires an electron transfer step followed by the formation of a σ-bond and the creation of a π-radical in the graphene lattice, and thus, there is the potential for unequal degrees of functionalization in the A and B sublattices and the possibility of ferromagnetism and superparamagnetism in the reaction products. With regard to metal functionalization, we distinguish four limiting cases: (a) weak physisorption, (b) ionic chemisorption, in which there is charge transfer to the graphitic structure and preservation of the conjugation and band structure, (c) covalent chemisorption, in which there is strong rehybridization of the graphitic band structure, and (d) covalent chemisorption with formation of an organometallic hexahapto-metal bond that largely preserves the graphitic band structure (constructive rehybridization). The constructive rehybridization that accompanies the formation of bis-hexahapto-metal bonds, such as those in (η(6)-SWNT)Cr(η(6)-SWNT), interconnects adjacent graphitic surfaces and significantly reduces the internanotube junction resistance in single-walled carbon nanotube (SWNT) networks. The conversion of sp(2) hybridized carbon atoms to sp(3) can introduce a band gap into graphene, influence the electronic scattering, and create dielectric regions in a graphene wafer. However, the organometallic hexahapto (η(6)) functionalization of the two-dimensional (2D) graphene π-surface with transition metals provides a new way to modify graphitic structures that does not saturate the functionalized carbon atoms and, by preserving their structural integrity, maintains the delocalization in these extended periodic π-electron systems and offers the possibility of three-dimensional (3D) interconnections between adjacent graphene sheets. These structures may find applications in interconnects, 3D-electronics, organometallic catalysis, atomic spintronics and in the fabrication of new electronic materials.

14.
Heliyon ; 10(2): e24756, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38298677

RESUMO

Cerebral small vessel disease (CSVD) is a leading cause of ischaemic and haemorrhagic stroke and a major contributor to dementia. It occurs mostly in adult patients, rarely in children. COL4A1 is a candidate gene in monogenic CSVD with a wide clinical and neuroimaing spectrum. Here we presented a 12-year-old girl with recurrent dizziness, mild learning difficulties and inability to concentrate, the brain MRI showed diffuse periventricular leukoencephalopathy, lacunes in bilateral centrum semiovale, periventricles and basal ganglia, dilated perivascular spaces in bilateral basal ganglia with brain MRA and MRV were normal, highly mimicked the neuroimaging of CSVD regardless of the young age and no episodes of cerebrovascular events for now. We found no vascular risk factors and excluded other diseases such as primary angitis of central nervous system (PACNS). Then a trio-whole exome sequencing was performed. We found a de novo variant of COL4A1 gene c.2662G>A (p.Gly888Arg). She was finally diagnosed as a MRI-defined covert CSVD case. Though there are no specific treatments, with the very early diagnosis in our patient, excessive physical activity, trauma, anticoagulant therapy should be avoided for possible strokes in her future life. Therefore, genetic screening should be considered in familial cases and also in sporadic cases even in pediatric patients when the brain MRI showed diffuse periventricular leukoencephalopathy, dilated perivascular spaces, as well as microhemorrhage, and deep intracerebral hemorrhages, associated with early onset ischemic strokes or not.

15.
J Med Case Rep ; 18(1): 303, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38918846

RESUMO

BACKGROUND: Hemorrhage is the most common major complication after liver biopsy. Hemothorax is one type of bleeding and is very rare and dangerous. Several cases of hemothorax subsequent to liver biopsy have been documented, primarily attributed to injury of the intercostal artery or inferior phrenic artery and a few resulting from lung tissue damage; however, no previous case report of hemothorax caused by injury of musculophrenic artery after liver biopsy has been reported. CASE PRESENTATION: A 45-year-old native Chinese woman diagnosed with primary biliary cirrhosis due to long-term redness in urination and abnormal blood test indicators was admitted to our hospital for an ultrasound-guided liver biopsy to clarify pathological characteristics and disease staging. A total of 2 hours after surgery, the patient complained of discomfort in the right chest and abdomen. Ultrasound revealed an effusion in the right thorax and hemothorax was strongly suspected. The patient was immediately referred to the interventional department for digital subtraction angiography. Super-selective angiography of the right internal thoracic artery was performed which revealed significant contrast medium extravasation from the right musculophrenic artery, the terminal branch of the internal thoracic artery. Embolization was performed successfully. The vital signs of the patient were stabilized after the transarterial embolization and supportive treatment. CONCLUSION: This case draws attention to the musculophrenic artery as a potential source of hemorrhage after percutaneous liver biopsy.


Assuntos
Embolização Terapêutica , Hemotórax , Fígado , Humanos , Hemotórax/etiologia , Feminino , Pessoa de Meia-Idade , Fígado/patologia , Fígado/diagnóstico por imagem , Fígado/irrigação sanguínea , Ultrassonografia de Intervenção , Biópsia Guiada por Imagem/efeitos adversos , Angiografia Digital
16.
Epilepsia Open ; 9(2): 643-652, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38235958

RESUMO

OBJECTIVE: To investigate the effectiveness and tolerability of ketogenic diet therapy (KDT) in patients with developmental and epileptic encephalopathy (DEE) associated with genetic etiology which onset within the first 6 months of life, and to explore the association between response to KDT and genotype/clinical parameters. METHODS: We retrospectively reviewed data from patients with genetic DEE who started KDT at Beijing Children's Hospital between January 1, 2016, and December 31, 2021. RESULTS: A total of 32 patients were included, involving 14 pathogenic or likely pathogenic single genes, and 16 (50.0%) patients had sodium/potassium channel gene variants. The median age at onset of epilepsy was 1.0 (IQR: 0.1, 3.0) months. The median age at initiation of KDT was 10.0 (IQR: 5.3, 13.8) months and the median duration of maintenance was 14.0 (IQR: 7.0, 26.5) months, with a mean blood ß-hydroxybutyrate of 2.49 ± 0.62 mmol/L. During the maintenance period of KDT, 26 (81.3%) patients had a ≥50% reduction of seizure frequency, of which 12 (37.5%) patients achieved seizure freedom. Better responses were observed in patients with STXBP1 variants, with four out of five patients achieving seizure freedom. There were no statistically differences in the age of onset, duration of epilepsy before KDT, blood ketone values, or the presence of ion channel gene variants between the seizure-free patients and the others. The most common adverse effects were gastrointestinal side effects, which occurred in 21 patients (65.6%), but all were mild and easily corrected. Only one patient discontinued KDT due to nephrolithiasis. SIGNIFICANCE: KDT is effective in treating early onset genetic DEE, and no statistically significant relationship has been found between genotype and effectiveness in this study. KDT is well tolerated in most young patients, with mild and reversible gastrointestinal side effects being the most common, but usually not the reason to discontinue KDT. PLAIN LANGUAGE SUMMARY: This study evaluated the response and side effects of ketogenic diet therapy (KDT) in patients who had seizures within the first 6 months of life, and were diagnosed with genetic developmental and epileptic encephalopathy (DEE), a type of severe epilepsy with developmental delay caused by gene variants. Thirty-two patients involving 14 gene variants who started KDT at Beijing Children's Hospital between were included. KDT was effective in treating early onset genetic DEE in this cohort, and patients with STXBP1 variants responded better; however, no statistically significant relationship was found between gene variant and response. Most young patients tolerated KDT well, with mild and reversible gastrointestinal side effects being the most common.


Assuntos
Dieta Cetogênica , Epilepsia , Criança , Humanos , Estudos Retrospectivos , Dieta Cetogênica/efeitos adversos , Epilepsia/genética , Convulsões , Genótipo , Corpos Cetônicos , Canais de Sódio/genética
17.
Pediatr Neurol ; 152: 98-106, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38242024

RESUMO

BACKGROUND: Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is considered a demyelinating disease of the central nervous system, but an increasing number of encephalitis cases associated with MOG antibodies have been reported recently. METHODS: This was a single-center, retrospective study. All data for pediatric patients with MOGAD diagnosed at Beijing Children's Hospital from January 2017 to January 2022 were collected. Clinical characteristics and outcomes were analyzed, and treatment responses were compared between the rituximab (RTX) and mycophenolate mofetil (MMF) groups. RESULTS: A total of 190 patients (age range: 5 months to 16 years; median age: 7.2 years; females: 97) were included in this study. The phenotypes of the first attack included acquired demyelinating syndromes (105 [55%]), encephalitis other than acute disseminated encephalomyelitis (82 [43%]), and isolated meningitis (3 [2%]). After a median follow-up of 30.4 months (interquartile range: 14.8-43.7), 64 (34%) patients had relapses. Fifty-one of the 64 (80%) patients who had relapse received maintenance therapy, including MMF (41), RTX (11), maintenance intravenous immunoglobulin (two), and tocilizumab (two). The annualized relapse rates decreased significantly after treatment in both the RTX and MMF cohorts (P < 0.05); however, there were no significant differences between the two groups (P = 0.56). A total of 178 (94%) patients had complete (175 patients) or almost complete (three patients) recovery (modified Rankin scale [mRS] < 2), and 12 had moderate to severe deficits (mRS ≥ 2). CONCLUSIONS: The spectrum of pediatric MOGAD is broader than previously reported and includes demyelinating syndromes and encephalitis. Encephalitis is an important initial phenotype observed in pediatric patients with MOGAD.


Assuntos
Autoanticorpos , Encefalite , Feminino , Humanos , Criança , Lactente , Estudos de Coortes , Glicoproteína Mielina-Oligodendrócito , Estudos Retrospectivos , Encefalite/tratamento farmacológico , Rituximab/uso terapêutico , Recidiva , Ácido Micofenólico
18.
Artigo em Inglês | MEDLINE | ID: mdl-37908058

RESUMO

Fiber-based supercapacitors (FSCs) exhibit desirable application potential and development prospects in wearable energy storage devices because of their flexibility and wearability. However, the low capacity in the unit volume and insufficient fiber strength hinder their further development in practical application. Herein, the MnO2 nanomaterials with regulatable crystalline structure were synthesized by one-step hydrothermal strategy. The formation of the MnO2 crystalline structure involved the "crimp-phase transition" process. Among them, the 2 × 2 tunnel type α-MnO2 nanowires exhibited excellent electrochemical capacitance (43.8 F g-1), high rate performance (61%, 0.25 to 6 A g-1), and remarkable cyclic stability (99%), which can be attributed to their good symmetry in space and high shared vertices proportion. On this basis, the α-MnO2 nanowires were coblended with GO to construct MnO2/rGO hybrid fibers by scalable continuous wet spinning and in situ acid reduction. Noteworthily, in MnO2/rGO hybrid fibers, the doping amount of MnO2 nanowires as high as 50 wt % could be achieved, while the strength reached 11.73 MPa, which can be ascribed to the superior surface morphology of MnO2 nanowires and the unique cement wall structure of hybrid fibers. Finally, the obtained hybrid fiber electrodes were assembled into symmetrical FSCs. Notably, the FSCs delivered remarkable volume specific capacitance (129.5 F cm-3) and impressive energy density (18 mWh cm-3) at 1.75 A cm-3. In addition, the assembled all-solid-state FSCs indicated excellent deformability and application potential. This work offers some insight for promoting the continuous preparation of fiber electrodes, the development of FSCs, and practical application in wearable energy textile.

19.
Brain Dev ; 45(8): 422-431, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37142513

RESUMO

PURPOSE: To evaluate the clinical spectrum associated with ATP1A2 variants in Chinese children with hemiplegia, migraines, encephalopathy or seizures. METHODS: Sixteen children (12 males and 4 females), including ten patients with ATP1A2 variants whose cases had been published previously, were identified using next-generation sequencing. RESULTS: Fifteen patients had FHM2 (familial hemiplegic migraine type 2), including three who had AHC (alternating hemiplegia of childhood) and one who had drug-resistant focal epilepsy. Thirteen patients had DD (developmental delay). The onset of febrile seizures, which occurred between 5 months and 2 years 5 months (median 1 year 3 months) was earlier than the onset of HM (hemiplegic migraine), which occurred between 1 year 5 months and 13 years (median 3 years 11 months). Disturbance of consciousness subsided first, at 40 h to 9 days (median 4.5 days); hemiplegia and aphasia were resolved slowly, taking 30 min to 6 months (median 17.5 days) for the former and 24 h to over 1 year (median 14.5 days) for the latter. Cranial MRI showed edema in the cerebral hemispheres, mainly the left hemisphereacute attacks. All thirteen FHM2 patients recovered to baseline in 30 min to 6 months. Fifteen patients had between 1 and 7 (median 2) total attacks between the baseline and follow-up timepoints. We report twelve missense variants, including a novel variant ATP1A2 variant, p.G855E. CONCLUSIONS: The known genotypic and phenotypic spectra of Chinese patients with ATP1A2-related disorders were further expanded. Recurrent febrile seizures and DD combined with paroxysmal hemiplegia and encephalopathy should raise the clinical suspicion of FHM2. The avoidance of triggers and thus the prevention of attacks may be the most effective therapy for FHM2.


Assuntos
Epilepsia Resistente a Medicamentos , Enxaqueca com Aura , Convulsões Febris , Masculino , Feminino , Humanos , Criança , Hemiplegia/genética , População do Leste Asiático , Mutação/genética , ATPase Trocadora de Sódio-Potássio/genética , Análise Mutacional de DNA
20.
Front Microbiol ; 14: 1293206, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38029151

RESUMO

Paraclostridium bifermentans (P.b) is an emerging human pathogen that is phylogenomically close to Paeniclostridium sordellii (P.s), while their populational genomic features and virulence capacity remain understudied. Here, we performed comparative genomic analyses of P.b and compared their pan-genomic features and virulence coding profiles to those of P.s. Our results revealed that P.b has a more plastic pangenome, a larger genome size, and a higher GC content than P.s. Interestingly, the P.b and P.s share similar core-genomic functions, but P.b encodes more functions in nutrient metabolism and energy conversion and fewer functions in host defense in their accessory-genomes. The P.b may initiate extracellular infection processes similar to those of P.s and Clostridium perfringens by encoding three toxin homologs (i.e., microbial collagenase, thiol-activated cytolysin, phospholipase C, which are involved in extracellular matrices degradation and membrane damaging) in their core-genomes. However, P.b is less toxic than the P.s by encoding fewer secretion toxins in the core-genome and fewer lethal toxins in the accessory-genome. Notably, P.b carries more toxins genes in their accessory-genomes, particularly those of plasmid origin. Moreover, three within-species and highly conserved plasmid groups, encoding virulence, gene acquisition, and adaptation, were carried by 25-33% of P.b strains and clustered by isolation source rather than geography. This study characterized the pan-genomic virulence features of P.b for the first time, and revealed that P. bifermentans is an emerging pathogen that can threaten human health in many aspects, emphasizing the importance of phenotypic and genomic characterizations of in situ clinical isolates.

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