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1.
J Am Chem Soc ; 146(10): 6697-6705, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38419157

RESUMO

Synthesizing large metal-organic framework (MOF) single crystals has garnered significant research interest, although it is hindered by the fast nucleation kinetics that gives rise to numerous small nuclei. Given the different chemical origins inherent in various types of MOFs, the development of a general approach to enhancing their crystal sizes presents a formidable challenge. Here, we propose a simple isotopic substitution strategy to promote size growth in MOFs by inhibiting nucleation, resulting in a substantial increase in the crystal volume ranging from 1.7- to 165-fold. Impressively, the crystals prepared under optimized conditions by normal approaches can be further enlarged by the isotope effect, yielding the largest MOF single crystal (2.9 cm × 0.48 cm × 0.23 cm) among the one-pot synthesis method. Detailed in situ characterizations reveal that the isotope effect can retard crystallization kinetics, establish a higher nucleation energy barrier, and consequently generate fewer nuclei that eventually grow larger. Compared with the smaller crystals, the isotope effect-enlarged crystal shows 33% improvement in the X-ray dose rate detection limit. This work enriches the understanding of the isotope effect on regulating the crystallization process and provides inspiration for exploring potential applications of large MOF single crystals.

2.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(1): 25-31, 2024 Jan 10.
Artigo em Chinês | MEDLINE | ID: mdl-38171555

RESUMO

OBJECTIVE: To explore the early neurodevelopmental features of young children with SYNGAP1 variants and their genotype-phenotype correlation. METHODS: Young children with neurodevelopmental disorders (NDDs) (< 5 years old) who were referred to the Children's Hospital Affiliated to the Capital Institute of Pediatrics between January 2019 and July 2022 were selected as the study subjects. All children had undergone whole-exome sequencing, comprehensive pediatric neuropsychological assessment, familial segregation analysis, and pathogenicity classification. Meanwhile, young Chinese NDD children (< 5 years old) with pathogenic/likely pathogenic SYNGAP1 variants were retrieved from the literature, with information including detailed clinical and genetic testing, neurodevelopmental quotient (DQ) of the Children Neuropsychological and Behavior Scale-Revision 2016 (CNBS-R2016). Children who did not have a detailed DQ but had their developmental status assessed by a medical professional were also included. The correlation between neurodevelopmental severity, comorbidity and SYNGAP1 variants were summarized. RESULTS: Four young NDD children carrying SYNGAP1 variants were recruited (1 male and 3 females, with a mean age of 34.0 ± 18.2 months), among whom one harboring a novel variant (c.437C>G, p.S146*). Combined with 19 similar cases retrieved from the literature, 23 Chinese NDD young children were included in our study (8 males and 10 females, 5 with unknown sex, with a mean age of 37.1 ± 14.2 months). A loss of function (LOF) variant was found in 19 (82.6%) children. All of the children had presented global developmental delay (GDD) before the age of two. In addition, 16 (69.6%) had seizure/epilepsy at the age of 27.0 ± 12.1 months, among whom 15 had occurred independent of the global developmental delay. Myoclonic and absence were common types of seizures. Compared with those with variants of exons 8 to 15, the severity of developmental delay was milder among children with variants in exons 1 to 5. CONCLUSION: The early neurodevelopment features of the SYNGAP1 variants for young children (< 5 years old) have included global developmental delay and seizure/epilepsy. All of the children may present GDD before the age of two. The severity of developmental delay may be related to the type and location of the SYNGAP1 variants.


Assuntos
Epilepsia , Transtornos do Neurodesenvolvimento , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Epilepsia/genética , Testes Genéticos , Genótipo , Transtornos do Neurodesenvolvimento/genética , Proteínas Ativadoras de ras GTPase/genética , Convulsões/genética
3.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(6): 595-599, 2023 Jun 15.
Artigo em Chinês | MEDLINE | ID: mdl-37382128

RESUMO

OBJECTIVES: To study the clinical features of children with febrile seizures after Omicron variant infection. METHODS: A retrospective analysis was performed on the clinical data of children with febrile seizures after Omicron variant infection who were admitted to the Department of Neurology, Children's Hospital Affiliated to the Capital Institute of Pediatrics, from December 1 to 31, 2022 (during the epidemic of Omicron variant; Omicron group), and the children with febrile seizures (without Omicron variant infection) who were admitted from December 1 to 31, in 2021 were included as the non-Omicron group. Clinical features were compared between the two groups. RESULTS: There were 381 children in the Omicron group (250 boys and 131 girls), with a mean age of (3.2±2.4) years. There were 112 children in the non-Omicron group (72 boys and 40 girls), with a mean age of (3.5±1.8) years. The number of children in the Omicron group was 3.4 times that in the non-Omicron group. The proportion of children in two age groups, aged 1 to <2 years and 6-10.83 years, in the Omicron group was higher than that in the non-Omicron group, while the proportion of children in two age groups, aged 4 to <5 years and 5 to <6 years, was lower in the Omicron group than that in the non-Omicron group (P<0.05).The Omicron group had a significantly higher proportion of children with cluster seizures and status convulsion than the non-Omicron group (P<0.05). Among the children with recurrence of febrile seizures, the proportion of children aged 6-10.83 years in the Omicron group was higher than that in the non-Omicron group, while the proportion of children aged 3 years, 4 years, and 5 years in the Omicron group was lower than that in the non-Omicron group (P<0.05). CONCLUSIONS: Children with febrile seizures after Omicron variant infection tend to have a wider age range, with an increase in the proportion of children with cluster seizures and status convulsion during the course of fever.


Assuntos
Epidemias , Epilepsia Generalizada , Convulsões Febris , Masculino , Feminino , Humanos , Criança , Lactente , Pré-Escolar , Convulsões Febris/etiologia , Estudos Retrospectivos , Convulsões , Febre
4.
ChemSusChem ; 15(11): e202200474, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35365962

RESUMO

The conventional thermal method of preparing hafnium alkoxides [Hf(OR)4 , R=alkyl] - excellent precursors for gate-dielectric HfO2 on semiconductors - is severely hindered by its unsatisfactory environmental and economic burdens. Herein, we propose a promising electrodissolution-coupled Hf(OR)4 synthesis (EHS) system for green and efficient electrosynthesis of Hf(OR)4 . The operational principle of the electrically driven system consists of two simultaneous heterogeneous reactions of Hf dissolution and alcohol dehydrogenation, plus a spontaneous solution-based combination reaction. In applying ethanol as solvent and Hf metal as electrodissolution medium, we achieved waste-free production of high-purity hafnium ethoxide [Hf(OEt)4 ] with an equivalent "a concomitant" reduction in CO2 emission of 187.33 g CO2 per kg Hf(OEt)4 and a high net profit of 30 477 USD per kg Hf(OEt)4 . This system is very competitive with the thermal process, which unavoidably releases substantial waste and CO2 for a net profit of 27 700 USD per kg Hf(OEt)4 . We anticipate that the environmental and economic benefits of the EHS process could pave the way for its practical application.


Assuntos
Dióxido de Carbono , Háfnio , Metais , Semicondutores , Solventes
5.
Genes (Basel) ; 13(3)2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35328089

RESUMO

Variants in NAA15 are closely related to neurodevelopmental disorders (NDDs). In this study, we investigated the spectrum and clinical features of NAA15 variants in a Chinese NDD cohort of 769 children. Four novel NAA15 pathogenic variants were detected by whole-exome sequencing, including three de novo variants and one maternal variant. The in vitro minigene splicing assay confirmed one noncanonical splicing variant (c.1410+5G>C), which resulted in abnormal mRNA splicing. All affected children presented mild developmental delay, and catch-up trajectories were noted in three patients based on their developmental scores at different ages. Meanwhile, the literature review also showed that half of the reported patients with NAA15 variants presented mild/moderate developmental delay or intellectual disability, and possible catch-up sign was indicated for three affected patients. Taken together, our study expanded the spectrum of NAA15 variants in NDD patients. The affected patients presented mild developmental delay, and possible catch-up developmental trajectories were suggested. Studying the natural neurodevelopmental trajectories of NDD patients with pathogenic variants and their benefits from physical rehabilitations are needed in the future for precise genetic counseling and clinical management.


Assuntos
Deficiência Intelectual , Acetiltransferase N-Terminal A , Acetiltransferase N-Terminal E , Transtornos do Neurodesenvolvimento , Povo Asiático , Criança , Estudos de Coortes , Humanos , Deficiência Intelectual/genética , Acetiltransferase N-Terminal A/genética , Acetiltransferase N-Terminal E/genética , Transtornos do Neurodesenvolvimento/patologia , Sequenciamento do Exoma/métodos
6.
Artigo em Inglês | MEDLINE | ID: mdl-33568421

RESUMO

Infantile spasms are a potentially catastrophic form of epilepsy syndrome that are usually associated with substantial developmental delay and commonly occur in children younger than 1 yr. Recent reports on four cases revealed that variants harbored in a novel gene CDK19 were causative for the syndrome. We report a fifth affected individual, a 10-mo-old male patient who presented with a neurodevelopmental syndrome characterized by infantile spasms. We identified a novel de novo missense variant c.92C > A (p.Thr31Asn) in CDK19 that was classified as a likely pathogenic disease-causing variant. The characterized clinical phenotypes of the proband were similar to the previously reported four patients, but he had few variable features including earlier seizure onset age and earlier occurring developmental abnormality. Protein structure modeling analysis revealed that CDK19 variants may disable its kinase activity, which would further impede the transcriptional regulation, thus leading to detrimental pathologies. Our report expanded CDK19 genotype spectrum and further demonstrated that a CDK19 missense variant was causative of neurodevelopmental disorder clinically marked by infantile spasms.


Assuntos
Quinases Ciclina-Dependentes/genética , Variação Genética , Transtornos do Neurodesenvolvimento/genética , Espasmos Infantis/genética , Quinases Ciclina-Dependentes/química , Síndromes Epilépticas , Humanos , Lactente , Masculino , Mutação de Sentido Incorreto , Transtornos do Neurodesenvolvimento/diagnóstico por imagem , Transtornos do Neurodesenvolvimento/patologia , Linhagem , Fenótipo , Convulsões/genética , Sequenciamento do Exoma
7.
R Soc Open Sci ; 6(1): 181193, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30800369

RESUMO

In order to identify a volatile metallo-organic precursor for the deposition of hafnium oxide (HfO2) films for atomic layer deposition (ALD) applications, the evaporative properties of hafnium alkoxides (hafnium isopropoxide, hafnium n-propoxide and hafnium n-butoxide) were investigated using thermogravimetric analysis. These hafnium alkoxide samples were synthesized by the electrochemical method and characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance and inductively coupled plasma analysis techniques. The characterization results indicated that the products were 99.997% high-purity hafnium alkoxides and could meet the requirement of purity considering the usage of making HfO2 gate oxide by ALD. Synthesized samples were subjected to a simultaneous thermogravimetric-differential thermal analysis unit at 10 K min-1 in a dry nitrogen atmosphere flowing at 100 ml min-1. Benzoic acid was used to calculate a calibration constant, which could then be inserted into a modified Langmuir equation to calculate vapour pressure curves for hafnium isopropoxide and hafnium n-propoxide. Detailed vapour pressure data for the HfO2 precursor hafnium alkoxides were determined. The vapour pressure curve of hafnium isopropoxide was constructed within the first stage, and calculated to be lnp = 31.157 (±0.200)-13130.57 (±56.50)/T. Hafnium n-propoxide and hafnium n-butoxide were simultaneously undergoing evaporation and decomposition, thus making calculations invalid.

8.
Waste Manag ; 75: 469-476, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29478957

RESUMO

The recycling of spent commercial lithium-ion batteries (LIBs) generates numerous environmental and economic benefits. In this research, a thermal treatment-ammoniacal leaching process is proposed to recover valuable metals from cathode active powder. Based on the thermal behavior by TG-DSC analysis, the cathode active powder is calcined at 300 °C and 550 °C in air atmosphere, and the crystalline phase characterization indicates that a new phase of Co3O4 appears in the cathode active powder calcined at 550 °C, which signifies that the layer structure of LiCoO2 collapses. The valence of manganese increases to form Li4Mn5O12 in spinel structure of LiMn2O4. Using calcined cathode powder as feed material, ammoniacal leaching is carried out in (NH4)2SO4 -(NH4)2SO3 solution. Under the optimum conditions, Ni, Co, Mn and Li can be completely leached out with efficiencies of 98%, 81%, 92% and 98%, respectively. However, with the increase of ammonia concentration, the leaching efficiency of Mn decreases dramatically to 4% due to the formation of double salts. It is found that Co and Mn can be precipitated into residues in the form of (NH4)2Co(SO4)2·H2O, (NH4)2Mn(SO3)2·H2O and (NH4)2Mn(SO4)2·6H2O under different leaching parameters. Based on the corresponding relationship between the leaching efficiency and phase evolution of object element, selective leaching can be achieved by controlling the formation of double salts.


Assuntos
Fontes de Energia Elétrica , Resíduo Eletrônico , Reciclagem , Eletrodos , Lítio , Metais
9.
J Hazard Mater ; 322(Pt B): 402-412, 2017 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-27773439

RESUMO

In this work, a new innovative slag cleaning technique was presented to economically and environmentally friendly recover valuable metals from cobalt-bearing copper smelter slag. CaSO4-rich gypsum waste was used as sulfurizing agent to efficiently and selectively sulfurize and recover valuable metals lost in the slag at reductive atmosphere. Thermodynamic analysis and laboratory experiments were carried out to determine the feasibility and reliability of this new process. The optimum slag cleaning conditions were determined as follow: reductive agent coke dosage of 12%, 20% CaSO4 addition of smelter slag weight, smelting at 1350°C for 3h. Under the optimum conditions, 92.04% Cu and 95.62% Co were enriched and recovered in copper-cobalt matte. The contents of Cu and Co in cleaned slag dropped to levels lower than 0.2% and 0.045% respectively. Selectivity recovery ratio of Cu/Fe and Co/Fe can reach 6.00 and 6.24 respectively. Calcium-rich and iron-poor cleaned slag property was more beneficial for minimizing cobalt and copper losses in slag. The products were characterized by XRD and SEM-EDS techniques. The Cu-Co matte primarily comprised iron sulphide (FeS), geerite (Cu8S5), iron cobalt sulphide (Fe0.92Co0.08S), independent cobalt sulphide (CoS) and some metallic Cu, Co and Fe. Copper and cobalt in resultant matte attended to appear separately in different mineral phases. The cleaned slag mainly contained fayalite (Fe2SiO4), hedenbergite (CaFeSi2O6) and magnetite (Fe3O4).

10.
Int J Clin Exp Pathol ; 8(8): 9337-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26464686

RESUMO

Methylmalonic aciduria and homocystinuria, cblC type, is the most common disorder of intracellular vitamin B12 (cobalamin, cbl) metabolism, which results in impaired biosynthesis of methylcobalamin and adenosylcobalamin. The gene MMACHC responsible for the cblC type had been identified, which enables molecular diagnostics. Here, we report four cblC type cases, which were identified by the typical manifestations, and a new approach of next-generation sequencing platform in pediatrics for genetic diseases, further confirmed by Sanger sequencing of the whole MMACHC gene. The article will replenish the mutational information of related genes to the cblC type, which makes for detecting of cblC disease through the newborn screening.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/genética , Proteínas de Transporte/genética , Homocistinúria/genética , Mutação , Deficiência de Vitamina B 12/congênito , Criança , Análise Mutacional de DNA , Feminino , Testes Genéticos , Humanos , Lactente , Oxirredutases , Deficiência de Vitamina B 12/genética
11.
J Hazard Mater ; 179(1-3): 1037-41, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20409636

RESUMO

In this study, heavy metals were removed and crude bio-oil was yielded from a heavy metal hyperaccumulator harvest, Sedum alfredii Hance, through hydrothermal upgrading process. This paper reports on the optimization of process parameters for the removal of heavy metals (zinc, lead, and copper) and for the upgrading of crude bio-oil from this biomass in an autoclave. Parameters such as granularity, temperature, pressure, and duration were examined for their effect on the removal efficiency of heavy metals and upgrading efficacy of crude bio-oil. Maximum heavy metal removal efficiency of >99% and crude bio-oil upgrading efficiency of >60% were attained with an 18 mesh (1 mm) granularity, and 22.1 MPa at 370 degrees C in the presence of 10 mg/L additives (K(2)CO(3)) for 60 s. Under these optimized conditions, an oil phase (mostly composed of phenolic hydrocarbons and derivatives), a water phase raffinate (containing Zn(2+) (0.39 g/L), Pb(2+) (0.10 g/L), Cu(2+) (0.15 g/L)), and a solid phase (the hydrothermal upgrading residue, which completely satisfies the limit set by China legislation related to biosolids disposal) were obtained.


Assuntos
Biocombustíveis/análise , Metais Pesados/isolamento & purificação , Sedum/química , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Pressão , Reprodutibilidade dos Testes , Temperatura , Termodinâmica , Água
12.
J Virol Methods ; 158(1-2): 100-3, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19428576

RESUMO

A method of loop-mediated isothermal amplification (LAMP) was employed to develop a rapid and simple detection system for porcine parvovirus (PPV) DNA. The amplification could be finished in 45 min under isothermal condition at 62 degrees C by employing a set of four primers targeting VP2 gene of PPV. LAMP assay showed higher sensitivity than PCR, with a detection limit of 5 copies of PPV genomic DNA per reaction. No cross reactivity was observed from the samples of other related viruses including canine parvovirus, parvovirus B19, porcine circovirus type 1, porcine circovirus type 2 and porcine peudorabies virus. The detection rate of PPV LAMP for 125 clinical samples was 97.6% and appeared higher than that of PCR method. The result indicated the potential usefulness of the technique as a simple, rapid procedure for the detection of PPV.


Assuntos
DNA Viral/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Infecções por Parvoviridae/veterinária , Parvovirus Suíno/isolamento & purificação , Doenças dos Suínos/diagnóstico , Animais , DNA Viral/genética , Infecções por Parvoviridae/diagnóstico , Parvovirus Suíno/genética , Sensibilidade e Especificidade , Suínos , Doenças dos Suínos/virologia , Temperatura , Fatores de Tempo
13.
Vet Res Commun ; 32(6): 491-8, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18481190

RESUMO

Avian influenza and Newcastle disease are the highly contagious and most economically important diseases in poultry industry throughout the world. A multiplex reverse transcription polymerase chain reaction (mRT-PCR) assay was developed for the rapid and specific discrimination of H5 and H9 subtypes of avian influenza viruses (AIV) and Newcastle disease virus (NDV). Three sets of specific primers were applied in the assay based on the sequences of the hemagglutinin gene of H5-AIV, H9-AIV and fusion protein gene of NDV. 59 clinical samples including the throat washes, oral swabs, and cloacal scrapings were detected by mRT-PCR and single RT-PCR (sRT-PCR), respectively. The results indicated that the sensitivity and specificity of mRT-PCR were in accordance with sRT-PCR. The mRT-PCR developed in this study may therefore provide a new avenue to rapid detection of these important pathogens in one reaction.


Assuntos
Virus da Influenza A Subtipo H5N1/classificação , Vírus da Influenza A Subtipo H9N2/classificação , Influenza Aviária/virologia , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/classificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Animais , Galinhas/virologia , Patos/virologia , Virus da Influenza A Subtipo H5N1/genética , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Doença de Newcastle/genética , Sensibilidade e Especificidade , Organismos Livres de Patógenos Específicos
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