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1.
Cell Biol Int ; 47(7): 1170-1182, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37269228

RESUMEN

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.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroARNs , Humanos , Carcinoma Hepatocelular/genética , Glucógeno Sintasa Quinasa 3 beta/genética , ARN Circular/genética , Neoplasias Hepáticas/genética , Carcinogénesis/genética , Transformación Celular Neoplásica , MicroARNs/genética , Proliferación Celular , Línea Celular Tumoral
2.
Dev Med Child Neurol ; 65(4): 534-543, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36175372

RESUMEN

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.


Asunto(s)
Epilepsia , Espasmos Infantiles , Masculino , Femenino , Humanos , Espasmos Infantiles/genética , Mutación , Epilepsia/genética , Convulsiones/genética , Estudios de Asociación Genética , Electroencefalografía , Dineínas Citoplasmáticas/genética
3.
Dev Med Child Neurol ; 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37960945

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-34263451

RESUMEN

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.


Asunto(s)
Canales de Calcio/genética , Epilepsia/genética , Mutación , Convulsiones/genética , Niño , Femenino , Estudios de Asociación Genética , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Recién Nacido , Masculino , Fenotipo
5.
Lasers Med Sci ; 36(9): 1873-1881, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33392781

RESUMEN

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.


Asunto(s)
Neoplasias Ováricas , Fotoquimioterapia , Apoptosis , Línea Celular Tumoral , Femenino , Humanos , Neoplasias Ováricas/tratamiento farmacológico , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico
6.
J Magn Reson Imaging ; 47(6): 1572-1577, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29236342

RESUMEN

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.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Enfermedades Renales/diagnóstico por imagen , Riñón/diagnóstico por imagen , Imagen por Resonancia Magnética , Uréter/diagnóstico por imagen , Obstrucción Ureteral/patología , Animales , Artefactos , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Fibrosis , Riñón/patología , Enfermedades Renales/patología , Modelos Lineales , Estudios Longitudinales , Masculino , Conejos , Uréter/patología
7.
Dev Med Child Neurol ; 60(6): 566-573, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29573403

RESUMEN

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.


Asunto(s)
Encefalopatías/diagnóstico por imagen , Encefalopatías/etiología , Epilepsias Mioclónicas/complicaciones , Estado Epiléptico , Edad de Inicio , Niño , Preescolar , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Lactante , Imagen por Resonancia Magnética , Masculino , Estado Epiléptico/complicaciones , Estado Epiléptico/diagnóstico por imagen , Estado Epiléptico/etiología
8.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 34(6): 787-791, 2017 Dec 10.
Artículo en Zh | MEDLINE | ID: mdl-29188601

RESUMEN

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.


Asunto(s)
Eliminación de Gen , Duplicación de Gen , Canal de Sodio Activado por Voltaje NAV1.1/genética , Epilepsias Mioclónicas/genética , Femenino , Humanos , Lactante , Masculino , Reacción en Cadena de la Polimerasa Multiplex
9.
J Am Chem Soc ; 138(1): 40-3, 2016 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-26675065

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-26244611

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-27706065

RESUMEN

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.


Asunto(s)
Escarabajos/microbiología , Lignina/metabolismo , Animales , Proteínas Bacterianas/metabolismo , Bacteroidetes/enzimología , Bacteroidetes/genética , Biomasa , Celulasa/metabolismo , Escarabajos/crecimiento & desarrollo , ADN Bacteriano/química , ADN Bacteriano/aislamiento & purificación , ADN Bacteriano/metabolismo , Firmicutes/enzimología , Firmicutes/genética , Larva/microbiología , Consorcios Microbianos , Análisis de Componente Principal , Proteobacteria/enzimología , Proteobacteria/genética , Análisis de Secuencia de ADN
12.
Nano Lett ; 14(7): 3930-7, 2014 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-24893323

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-23116475

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-38298677

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-38918846

RESUMEN

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.


Asunto(s)
Embolización Terapéutica , Hemotórax , Hígado , Humanos , Hemotórax/etiología , Femenino , Persona de Mediana Edad , Hígado/patología , Hígado/diagnóstico por imagen , Hígado/irrigación sanguínea , Ultrasonografía Intervencional , Biopsia Guiada por Imagen/efectos adversos , Angiografía de Substracción Digital
16.
Ital J Pediatr ; 50(1): 134, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39075561

RESUMEN

BACKGROUND: To understand the clinical characteristics and prognosis of respiratory syncytial virus (RSV)-related encephalopathy in children. METHODS: A retrospective analysis of the data of children who were diagnosed with RSV-related encephalopathy and admitted to the paediatric intensive care unit (PICU) of Beijing Children's Hospital between November 2016 and November 2023 was performed. RESULTS: Four hundred and sixty-four children with RSV infection were treated in the PICU, and eight of these patients (1.7%) were diagnosed with RSV-related encephalopathy. The mean age of the patients was 24.89 (5.92 ∼ 36.86) months. Two patients had underlying diseases. The time from the onset of illness to impaired consciousness was 3 (1.88-3.75) days. Five patients had convulsions, and three patients had an epileptic status. The serum procalcitonin (PCT) level was 1.63 (0.24, 39.85) ng/ml for the eight patients, and the cerebrospinal fluid (CSF) protein level was 232 (163 ∼ 848) g/L. Among the 8 patients, four patients underwent electroencephalogram (EEG) monitoring or examination. One patient showed continuous low-voltage, nonresponsive activity, and another patient displayed persistent slow waves, the remaining two patients had negative results. One patient had a combination of acute necrotizing encephalopathy (ANE) and acute encephalopathy with biphasic seizures and late reduced diffusion (AESD). Additionally, one patient had ANE, and another had acute brain swelling (ABS). One patient died in the hospital, and the other seven patients were discharged with improvement. Routine follow-up was conducted for 4.58(0.5 ∼ 6.50) years, and all patients fully recovered. CONCLUSIONS: RSV-related encephalopathy could have varying clinical manifestations, and some types, such as ANE and ABS, are dangerous and can lead to death.


Asunto(s)
Infecciones por Virus Sincitial Respiratorio , Humanos , Masculino , Femenino , Estudios Retrospectivos , Infecciones por Virus Sincitial Respiratorio/complicaciones , Infecciones por Virus Sincitial Respiratorio/diagnóstico , Pronóstico , Preescolar , Lactante , Electroencefalografía , Unidades de Cuidado Intensivo Pediátrico , Encefalopatías/diagnóstico , Encefalopatías/virología
17.
Pediatr Neurol ; 152: 98-106, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38242024

RESUMEN

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.


Asunto(s)
Autoanticuerpos , Encefalitis , Femenino , Humanos , Niño , Lactante , Estudios de Cohortes , Glicoproteína Mielina-Oligodendrócito , Estudios Retrospectivos , Encefalitis/tratamiento farmacológico , Rituximab/uso terapéutico , Recurrencia , Ácido Micofenólico
18.
Epilepsia Open ; 9(2): 643-652, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38235958

RESUMEN

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.


Asunto(s)
Dieta Cetogénica , Epilepsia , Niño , Humanos , Estudios Retrospectivos , Dieta Cetogénica/efectos adversos , Epilepsia/genética , Convulsiones , Genotipo , Cuerpos Cetónicos , Canales de Sodio/genética
19.
Artículo en Inglés | MEDLINE | ID: mdl-37908058

RESUMEN

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.

20.
Front Microbiol ; 14: 1293206, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38029151

RESUMEN

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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