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1.
Org Lett ; 26(25): 5335-5340, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38885466

RESUMEN

Here we disclose a CuB-catalyzed reaction between aurone-derived α,ß-unsaturated imines and styrenes to produce 2-substituted benzofuran derivatives bearing both the γ-boryl functionality and α,ß-unsymmetric stereogenic centers. The reaction represents the first transition-metal-catalyzed unsymmetric 1,4-Michael additions of azadienes, which would enrich the arsenal of CuB catalysis in organic synthesis. In addition, the synthetically versatile boron-alkylated products can be elaborated by chemical transformations to useful optically active benzofuran heterocycles.

2.
Mol Genet Genomic Med ; 12(5): e2447, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38733165

RESUMEN

BACKGROUND: Cornelia de Lange syndrome (CdLS) is a multisystem genetic disorder, and cases caused by variants in the structural maintenance of chromosomes protein 3 (SMC3) gene are uncommon. Here, we report two cases of CdLS associated with novel pathogenic variants in SMC3 from two Chinese families. METHODS: Clinical presentations of two patients with CdLS were evaluated, and specimens from the patients and other family members were collected for Trio-based whole-exome sequencing. Pyrosequencing, chip-based digital PCR, minigene splicing assay, and in silico analysis were carried out to elucidate the impact of novel variants. RESULTS: Novel heterozygous variants in SMC3 were identified in each proband. One harbored a novel splicing and mosaic variant (c.2535+1G>A) in SMC3. The mutated allele G>A conversion was approximately 23.1% by digital PCR, which indicated that 46.2% of peripheral blood cells had this variant. Additionally, in vitro minigene splicing analysis validated that the c.2535+1G>A variant led to an exon skipping in messenger RNA splicing. The other carried a heterozygous variant (c.435C>A), which was predicted to be pathogenic as well as significantly altered in local electrical potential. The former showed multiple abnormalities and marked clinical severity, and the latter mainly exhibited a speech developmental disorder and slightly facial anomalies. CONCLUSION: Both patients were clinically diagnosed with Cornelia de Lange syndrome 3 (CdLS3). The newly identified SMC3 gene variants can expand the understanding of CdLS3 and provide reliable evidence for genetic counseling to the affected family.


Asunto(s)
Proteínas de Ciclo Celular , Proteínas Cromosómicas no Histona , Síndrome de Cornelia de Lange , Femenino , Humanos , Masculino , Proteínas de Ciclo Celular/genética , Proteoglicanos Tipo Condroitín Sulfato , Proteínas Cromosómicas no Histona/genética , Síndrome de Cornelia de Lange/genética , Síndrome de Cornelia de Lange/patología , Heterocigoto , Mutación , Linaje , Fenotipo , Empalme del ARN
3.
ACS Appl Mater Interfaces ; 16(15): 19235-19246, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38584351

RESUMEN

The ability of ferroelectric memristors to modulate conductance and offer multilevel storage has garnered significant attention in the realm of artificial synapses. On one hand, the resistance change of ferroelectric memristors mainly depends on the polarization reversal. On the other hand, the defects such as oxygen vacancies, which are inevitable presence during high-temperature processes, can undergo diffusion drift with the polarization reversal, thereby change the interface potential barrier. Thus, it is both desirable and necessary to investigate the synergistic effect of ferroelectricity and defects. Here, we prepare BaTiO3 ferroelectric memristor by pulse laser deposition and achieve resistance switching through the synergistic effect of ferroelectricity and oxygen vacancies. The memristor shows excellent switching characteristics with a large switching ratio (104) and good stability (103 s). It effectively emulates the features of artificial synapses and accomplishes decimal logical neural computing. In the neuromorphic system crafted with the memristor, the recognition accuracy of the 28 × 28 pixel image reaches 94.9%. These findings strongly support the research of ferroelectric memristors in neuromorphic devices.

4.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(4): 437-442, 2024 Apr 10.
Artículo en Chino | MEDLINE | ID: mdl-38565509

RESUMEN

OBJECTIVE: To explore the clinical phenotype and genetic characteristics of a Chinese pedigree affected with Spastic paraplegia type 5A (SPG5A). METHODS: A pedigree suspected for Hereditary spastic paraplegia (HSP) at Henan Children's Hospital on August 15 2022 was selected as the study subject. Clinical data of the pedigree was collected. Peripheral blood samples were collected from members of the pedigree. Following extraction of genomic DNA, trio-WGS was carried out, and candidate variant was verified by Sanger sequencing. RESULTS: The child, a 1-year-old boy, had presented with microcephaly, hairy face and dorsal side of distal extremities and trunk, intellectual and motor development delay, increased muscle tone of lower limbs, hyperreflexes of bilateral knee tendons, and positive pathological signs. His parents and sister both had normal phenotypes. Trio-WGS revealed that the child has harbored a homozygous c.1250G>A (p.Arg417His) variant of the CYP7B1 gene, for which his mother was heterozygous, the father and sister were of the wild type. The variant was determined to have originated from maternal uniparental disomy (UPD). The result of Sanger sequencing was in keeping with the that of trio-WGS. SPG5A due to maternal UPD of chromosome 8 was unreported previously. CONCLUSION: The child was diagnosed with SPG5A, a complex type of HSP, for which the homozygous c.1250G>A variant of the CYP7B1 gene derived from maternal UPD may be accountable.


Asunto(s)
Paraplejía Espástica Hereditaria , Humanos , Lactante , Masculino , China , Mutación , Paraplejía/genética , Linaje , Fenotipo , Paraplejía Espástica Hereditaria/genética
5.
J Colloid Interface Sci ; 666: 371-379, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38603879

RESUMEN

VO2 (B) is recognized as a promising cathode material for aqueous zinc metal batteries (AZMBs) owing to its remarkable specific capacity and its unique, expansive tunnel structure, which facilitates the reversible insertion and extraction of Zn2+. Nonetheless, challenges such as the inherent instability of the VO2 structure, poor ion/electron transport and a limited capacity due to the low redox potential of the V3+/V4+ couple have hindered its wider application. In this study, we present a strategy to replace vanadium ions by doping Al3+ in VO2. This approach activates the multi-electron reaction (V4+/V5+), to increase the specific capacity and improve the structural stability by forming robust V5+O and Al3+O bonds. It also induces a local electric field by altering the local electron arrangement, which significantly accelerates the ion/electron transport process. As a result, Al-doped VO2 exhibits superior specific capacity, improved cycling stability, and accelerated electronic transport kinetics compared to undoped VO2. The beneficial effects of heterogeneous atomic doping observed here may provide valuable insights into the improvement electrode materials in metal-ion battery systems other than those based on Zn.

6.
Front Endocrinol (Lausanne) ; 15: 1323947, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38405141

RESUMEN

Introduction: Pineal cysts have long been considered a benign intracranial variation. However, in our clinical practice, it has been observed that some children with central precocious puberty (CPP) who have pineal cysts experience rapid progression in adolescent development. In recent years, there has been a significant increase in the prevalence of CPP in girls, leading to more diagnoses of CPP among children with pineal cysts. Despite this, there is no consensus regarding whether pineal cysts contribute to CPP as one of its organic factors. This study aimed to analyze the clinical characteristics of pineal cysts in children with CPP and explore the potential effects of pineal cysts on puberty development. Methods: This single-center study retrospectively analyzed clinical data from girls aged 3 to 10 years who underwent head/pituitary magnetic resonance imaging at the Children's Hospital Affiliated to Zhengzhou University between 2019 and 2022. The study categorized the detection rates of pineal cysts based on systematic disease classification and compared the rates of cyst detection between girls diagnosed with CPP and those without CPP. Subsequently, CPP-diagnosed girls with pineal cysts were examined. Among CPP-diagnosed girls meeting the study's criteria, those with pineal cysts formed the 'cyst group,' while those without cysts were matched in a 1:1 ratio based on age and body mass index to form the 'non-cyst group.' Comparative analyses were conducted to assess the clinical characteristics between these two groups. CPP-diagnosed girls with cysts were further subdivided into three groups according to cyst size (≤5 mm, 5.1-9.9 mm, and ≥10 mm) to investigate potential differences in clinical characteristics among these subgroups. The study involved an analysis of clinical data from girls diagnosed with CPP and included imaging follow-ups to explore the progression of pineal cysts over time. Results: Among the 23,245 girls who underwent head/pituitary magnetic resonance imaging scans, the detection rate of pineal cysts was 3.6% (837/23,245), with most cases being associated with endocrine diseases. The detection rate of pineal cysts in CPP patients was 6.4% (262/4099), which was significantly higher than the 3.0% (575/19,146) in patients without CPP. In comparison to the non-cyst group, the cyst group exhibited statistically significant increases in estradiol levels, peak luteinizing hormone (LH) levels, peak LH/follicle-stimulating hormone (FSH) ratios, uterine body length, and cervix length (P < 0.001). As cyst size increased, there were significant rises in LH peak, peak LH/FSH ratio, uterine body length, and cervical length (P < 0.01). Estradiol levels and left ovarian volume also showed an increasing trend (P < 0.05). Among girls who underwent follow-up imaging, 26.3% (5/19) exhibited an increase in cyst size. Conclusion: Pineal cysts are relatively common in children with CPP. They may affect the pubertal development process, with larger cysts correlating to faster pubertal development. Therefore, the authors hypothesize that pineal cysts may trigger CPP in some cases, especially when the cysts are larger than 5 mm in size, as indicated by our data.


Asunto(s)
Quistes del Sistema Nervioso Central , Quistes , Pubertad Precoz , Niño , Femenino , Humanos , Adolescente , Hormona Luteinizante , Pubertad Precoz/diagnóstico , Estudios Retrospectivos , Hormona Folículo Estimulante , Quistes/complicaciones , Quistes/diagnóstico por imagen , Hormona Folículo Estimulante Humana , Quistes del Sistema Nervioso Central/complicaciones , Quistes del Sistema Nervioso Central/diagnóstico por imagen , Estradiol
7.
J Hum Genet ; 69(5): 197-203, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38374166

RESUMEN

CAPZA2 encodes the α2 subunit of CAPZA, which is vital for actin polymerization and depolymerization in humans. However, understanding of diseases associated with CAPZA2 remains limited. To date, only three cases have been documented with neurodevelopmental abnormalities such as delayed motor development, speech delay, intellectual disability, hypotonia, and a history of seizures. In this study, we document a patient who exhibited seizures, mild intellectual disability, and impaired motor development yet did not demonstrate speech delay or hypotonia. The patient also suffered from recurrent instances of respiratory infections, gastrointestinal and allergic diseases. A novel de novo splicing variant c.219+1 G > A was detected in the CAPZA2 gene through whole-exome sequencing. This variant led to exon 4 skipping in mRNA splicing, confirmed by RT-PCR and Sanger sequencing. To our knowledge, this is the third study on human CAPZA2 defects, documenting the fourth unambiguously diagnosed case. Furthermore, this splicing mutation type is reported here for the first time. Our research offers additional support for the existence of a CAPZA2-related non-syndromic neurodevelopmental disorder. Our findings augment our understanding of the phenotypic range associated with CAPZA2 deficiency and enrich the knowledge of the mutational spectrum of the CAPZA2 gene.


Asunto(s)
Proteína CapZ , Discapacidades del Desarrollo , Epilepsia , Heterocigoto , Hipotonía Muscular , Mutación , Preescolar , Femenino , Humanos , Masculino , Discapacidades del Desarrollo/genética , Discapacidades del Desarrollo/patología , Epilepsia/genética , Secuenciación del Exoma , Discapacidad Intelectual/genética , Discapacidad Intelectual/patología , Hipotonía Muscular/genética , Hipotonía Muscular/patología , Fenotipo , Empalme del ARN/genética , Proteína CapZ/genética
8.
Pest Manag Sci ; 80(6): 2596-2609, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38252701

RESUMEN

BACKGROUND: Plutella xylostella (Linnaeus) is a destructive pest of cruciferous crops due to its strong reproductive capacity and extensive resistance to pesticides. Seminal fluid proteins (SFPs) are the main effective factors that determine the reproductive physiology and behaviour of both sexes. Although an increasing number of SFPs have been identified, the effects of astacins in SFPs on agricultural pests have not yet been reported. Here, we elucidated the mechanisms by which Sast1 (seminal astacin 1) regulates the fertility of Plutella xylostella (L.). RESULTS: PxSast1 was specifically expressed in the testis and accesssory gland. CRISPR/Cas9-induced PxSast1 knockout successfully constructed two homozygous mutant strains. Sast1 impaired the fertility of P. xylostella by separately regulating the reproductive capacity of males and females. Loss of PxSast1, on the one hand, significantly decreased the ability of males to mate and fertilize, mainly manifested as shortened mating duration, reduced mating competitiveness and decreased eupyrene sperm production; on the other hand, it significantly inhibited the expression of chorion genes in females, resulting in oogenesis deficits. Simultaneously, for mated females, the differentially expressed genes in signalling pathways related to oogenesis and chorion formation were significantly enriched after PxSast1 knockout. CONCLUSION: These analyses of the functions of PxSast1 as the regulator of spermatogenesis and oogenesis establish its importance in the fertility process of P. xylostella, as well as its potential as a promising target for genetic regulation-based pest control. © 2024 Society of Chemical Industry.


Asunto(s)
Proteínas de Insectos , Mariposas Nocturnas , Animales , Femenino , Masculino , Fertilidad , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Mariposas Nocturnas/genética , Mariposas Nocturnas/crecimiento & desarrollo , Proteínas de Plasma Seminal/genética , Proteínas de Plasma Seminal/metabolismo
9.
J Colloid Interface Sci ; 659: 267-275, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38176236

RESUMEN

Vanadium-based materials are widely recognized as the primary candidate cathode materials for aqueous Zn-ion batteries (AZIBs). However, slow kinetics and poor stability pose significant challenges for widespread application. Herein, to address these issues, alkali metal ions and polyaniline (PANI) are introduced into layered hydrated V2O5 (VO). Density functional theory calculations reveal that the synthesized (C6H4NH)0.27K0.24V2O5·0.92H2O (KPVO), with K+ and PANI co-intercalation, exhibits a robust interlayer structure and a continuous three-dimensional (3D) electron transfer network. These properties facilitate the reversible diffusion of Zn2+ with a low migration potential barrier and rapid response kinetics. The KPVO cathode exhibits a discharge specific capacity of 418.3 mAh/g at 100 mA/g and excellent cycling stability with 89.5 % retention after 3000 cycles at 5 A/g. This work provides a general strategy for integrating cathode materials to achieve high specific capacity and excellent kinetic performance.

10.
Nanotechnology ; 35(8)2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-37995377

RESUMEN

In recent years, the synaptic properties of transistors have been extensively studied. Compared with liquid or organic material-based transistors, inorganic solid electrolyte-gated transistors have the advantage of better chemical stability. This study uses a simple, low-cost solution technology to prepare In2O3transistors gated by AlLiO solid electrolyte. The electrochemical performance of the device is achieved by forming a double electric layer and electrochemical doping, which can mimic basic functions of biological synapses, such as excitatory postsynaptic current, paired-pulse promotion, and spiking time-dependent plasticity. Furthermore, complex synaptic behaviors such as Pavlovian classical conditioning is successfully emulated. With a 95% identification accuracy, an artificial neural network based on transistors is built to recognize sign language and enable sign language interpretation. Additionally, the handwriting digit's identification accuracy is 94%. Even with various levels of Gaussian noise, the recognition rate is still above 84%. The above findings demonstrate the potential of In2O3/AlLiO TFT in shaping the next generation of artificial intelligence.

11.
Nanotechnology ; 34(47)2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37604148

RESUMEN

Prussian blue analogues (PBAs) are reliable and promising cathode materials for aqueous sodium-ion batteries (ASIBs) owing to their open three-dimensional frameworks, outstanding stability, and low production costs. However, PBAs containing only a single type of transition-metal ion often have limited charge-storage capacities in aqueous systems. This study reports the first example of K0.11Ni0.39Co0.79[Fe(CN)6]·2.04H2O nanoparticles (Ni/Co-PBA) being used as a high-capacity cathode material for ASIBs. Owing to multi-electron redox reactions involving Co and Fe ions, Ni/Co-PBA has an initial capacity of 65 mAh g-1and a capacity retention rate of 80% after 1000 cycles at 1.0 A g-1, indicating its outstanding cycle performance and capacity retention. Ex-situ x-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, x-ray photoelectron spectroscopy, cyclic voltammetry, electrochemical impedance spectroscopy, and the galvanostatic intermittent titration technique were used to analyze the redox mechanisms and kinetics of Ni/Co-PBA. Ni/Co-PBA-based ASIBs are among the most promising energy-storage technologies for large-scale fixed energy-storage systems because of their outstanding electrochemical performance, low costs, and high efficiency.

12.
Nanotechnology ; 34(30)2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37094562

RESUMEN

Lithium supply shortages have prompted the search for alternatives to widespread grid system applications. Potassium-ion batteries (PIBs) have emerged to promising candidates for this purpose. Nonetheless, the large radius of K+(1.38 Å) impedes the march of satisfactory cathode materials. Here, we used solid-phase synthesis to prepare a layered K0.37MnO2·0.25H2O (KMO) cathode, comprising alternately connected MnO6octahedra with a large interlayer spacing (0.71 nm) to accommodate the migration and transport of K+ions. The cathode material achieved initial specific capacities of 102.3 and 88.1 mA h g-1at current densities of 60 mA g-1and 1 A g-1, respectively. The storage mechanism of K+ions in PIBs was demonstratedex situusing x-ray diffraction, x-ray photoelectron spectroscopy, and Raman spectroscopy measurements. Overall, our proposed KMO was confirmed as an auspicious cathode material for potential use in PIBs.

13.
Org Lett ; 24(44): 8213-8217, 2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36321660

RESUMEN

A CuH-catalyzed coupling of aryl alkenes with 3-aryl-2H-azirines has been developed to synthesize optically active ß,ß-disubstituted ketones. We propose that this protocol occurs through a sequence in which a chiral alkylcopper complex regioselectively attacks the N-C2 bonds of azirines to generate chiral ß-aryl imines, which additionally afford ketones upon hydrolysis. This method provides a novel complementary approach for synthesizing chiral ß,ß-disubstituted ketones in good yields with high levels of enantioselectivity under mild conditions.

14.
Int J Mol Sci ; 23(17)2022 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-36076934

RESUMEN

Vitelline membrane proteins (VMPs) are the main proteins that form the inner shell (vitelline membrane layer) of insect eggs and are an integral part of egg formation and embryo development. Here, we characterized the molecular structure and expression patterns of the VMP26 gene and analyzed its reproductive functions in diamondback moth, Plutella xylostella (L.), a worldwide migratory pest of cruciferous plants. The PxVMP26 gene was shown to be a single exon gene that contained an open reading frame of 852 base pairs (bp) encoding 283 amino acids. Both qPCR and western blot analyses showed that PxVMP26 was specifically expressed in female adults and was significantly highly expressed in the ovary. Further anatomical analysis indicated that the expression level of PxVMP26 in the ovarian tube with an incomplete yolk was significantly higher than that in the ovarian tube with a complete yolk. CRISPR/Cas9-induced PxVMP26 knockout successfully created two homozygous strains with 8- and 46-bp frameshift mutations. The expression deficiency of the PxVMP26 protein was detected in the mutant strains using immunofluorescence and western blot. No significant difference was found in the number of eggs laid within three days between wild and mutant individuals, but there was a lower egg hatchability. The loss of the PxVMP26 gene changed the mean egg size, damaged the structure of the vitelline membrane, and increased the proportion of abnormal eggs due to water loss, resulting in egg collapse. This first analysis of the roles of the VMP gene in the oocyte formation and embryonic development of P. xylostella, using CRISPR/Cas9 technology, provides a basis for screening new genetic control targets of P. xylostella.


Asunto(s)
Sistemas CRISPR-Cas , Mariposas Nocturnas , Animales , Sistemas CRISPR-Cas/genética , Proteínas del Huevo , Femenino , Mariposas Nocturnas/metabolismo , Mutagénesis , Membrana Vitelina
15.
Nucleic Acids Res ; 50(13): 7560-7569, 2022 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-35819229

RESUMEN

5'-Adenylated oligonucleotides (AppOligos) are widely used for single-stranded DNA/RNA ligation in next-generation sequencing (NGS) applications such as microRNA (miRNA) profiling. The ligation between an AppOligo adapter and target molecules (such as miRNA) no longer requires ATP, thereby minimizing potential self-ligations and simplifying library preparation procedures. AppOligos can be produced by chemical synthesis or enzymatic modification. However, adenylation via chemical synthesis is inefficient and expensive, while enzymatic modification requires pre-phosphorylated substrate and additional purification. Here we cloned and characterized the Pfu RNA ligase encoded by the PF0353 gene in the hyperthermophilic archaea Pyrococcus furiosus. We further engineered fusion enzymes containing both Pfu RNA ligase and T4 polynucleotide kinase. One fusion enzyme, 8H-AP, was thermostable and can directly catalyze 5'-OH-terminated DNA substrates to adenylated products. The newly discovered Pfu RNA ligase and the engineered fusion enzyme may be useful tools for applications using AppOligos.


Asunto(s)
Adenosina Monofosfato/química , Técnicas Genéticas , MicroARNs , Oligonucleótidos/química , Polinucleótido 5'-Hidroxil-Quinasa , ADN/química , ADN Ligasas/metabolismo , ADN de Cadena Simple , Polinucleótido 5'-Hidroxil-Quinasa/genética , Pyrococcus furiosus/enzimología , ARN Ligasa (ATP)/metabolismo
16.
ChemSusChem ; 15(16): e202200706, 2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-35666035

RESUMEN

The limited availability of cathode materials with high specific capacity and significant cycling stability for aqueous K-ion batteries (AKIBs) hinder their further development owing to the large radius of K+ (1.38 Å). Prussian blue and its analogs with a three-dimensional frame structure possessing special energy storage mechanism are promising candidates as cathode materials for AKIBs. In this study, K0.2 Ni0.68 Co0.77 Fe(CN)6 ⋅ 1.8H2 O (KNCHCF) was prepared as a cathode material for AKIBs. Both the electrochemical activity of Co ions and the near-pseudocapacitance intercalation of KNCHCF enhance K+ storage. Therefore, KNCHCF exhibits a superior capacity maintenance rate of 86 % after 1000 cycles at a high current density of 3.0 A g-1 . The storage mechanism of K+ in AKIBs was revealed through ex situ X-ray diffraction, ex situ Fourier transform infrared spectroscopy, and ex situ X-ray photoelectron spectroscopy measurements. Moreover, the assembled K-Zn hybrid battery showed good cycling stability with 93.1 % capacity maintenance at 0.1 A g-1 after 50 cycles and a high energy density of 96.81 W h kg-1 . Hence, KNCHCF may be a potential material for the development of AKIBs.

17.
Org Lett ; 24(1): 268-273, 2022 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-34889615

RESUMEN

Chemodivergent Pd-catalyzed annulations of cyclic ß-keto esters with 3-aryl-2H-azirines have been developed to provide rapid access to eight-membered ring lactams, bicyclic 3,4-dihydro-2H-pyrrole derivatives, and (E)-methyl [2-(2-oxocyclohexylidene)-2-phenylethyl]carbamates with high efficiency. The chemoselectivity can be determined by tuning the mono- or bisphosphine ligands as well as the substrate structure of cyclic ß-keto esters.

18.
J Orthop Surg Res ; 16(1): 250, 2021 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-33849595

RESUMEN

BACKGROUND: An observational study was conducted to evaluate the recovery of older children with relapsed congenital clubfoot who underwent an Achilles tenotomy for the second time as part of the Ponseti treatment. METHODS: Thirteen patients (19 feet) with congenital clubfoot underwent Achilles tenotomy where magnetic resonance images of the severed tendons were taken after 1, 3, and 6 weeks post-procedure. The participants were categorized into older children who underwent tenotomy for the first time (group A: mean, 4.9±1.8, and range, 2.8-7 years old) and older children who underwent tenotomy for a second time (group B: mean, 4.9±1.5, and range, 3-6.8 years old). The area of high signal intensity between the severed tendons on MRI scans was computed using Python programming language and compared with clinical assessment. RESULTS: Three weeks after Achilles tenotomy, groups A and B had clinically intact tendons in 9 out of 11 and 2 out of 8 feet, respectively, according to both clinical and MRI assessment. From week 1 to week 3 post-tenotomy, computational analysis showed that the mean high signal intensity area of group A decreased by 88.5±15.2%, which was significantly different (P .048 < .05) than the percent reduction of high signal intensity area of group B (69.0±24.9%). CONCLUSION: Children who underwent Achilles tenotomy for the second time showed slower tendon recovery on the third week post-procedure. A possible reason for slower healing times may be due to the location of tenotomy in being further away from the musculotendinous junction where extrinsic healing mechanisms take place.


Asunto(s)
Tendón Calcáneo/cirugía , Pie Equinovaro/diagnóstico por imagen , Pie Equinovaro/cirugía , Imagen por Resonancia Magnética/métodos , Recuperación de la Función , Tenotomía/métodos , Factores de Edad , Niño , Preescolar , Pie Equinovaro/fisiopatología , Femenino , Humanos , Masculino , Recurrencia , Reoperación , Resultado del Tratamiento
19.
Nanotechnology ; 32(31)2021 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-33906187

RESUMEN

Rechargeable aqueous zinc-ion batteries (AZIBs) have garnered widespread attention as a new large-scale energy storage candidate owing to their low cost and high theoretical capacity. Because of the unique divalent state of Zn2+and the existence of a strong electrostatic repulsion phenomenon, researchers are currently focusing on how to prepare high-performance cathode materials. In this study, we synthesized aluminum vanadate (AlV3O9) as a cathode material for AZIBs using a solvothermal method. Al3+acted as a pillar in the resultant structure and stabilized it. Furthermore, this large interlayer spacing enhanced the ion diffusion coefficient and accelerated the ion transport process. Because of these advantages, the AlV3O9(AVO) cathode exhibited excellent electrochemical performance, including a high capacity of 421.0 mA h g-1at 0.1 A g-1and a stable rate capability of 348.2 mA h g-1at 1 A g-1. Moreover, it exhibited a specific capacity of 202 mA h g-1even at a high current density of 3 A g-1(the capacity retention rate reached 84.38% after 1600 cycles). The prepared ZIBs presented a high power density of 366.6 W kg-1at an energy density of 286 W h kg-1. These extraordinary results indicate the great application potential of AVO as a cathode material for AZIBs.

20.
ChemSusChem ; 14(9): 2093-2099, 2021 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-33751834

RESUMEN

Rechargeable magnesium batteries (RMBs) have attracted significant attention owing to the high energy density and economic viability. However, the lack of suitable cathode materials, owing to the high polarizability of divalent Mg-ion and slow Mg-ion diffusion, hinders the development of RMBs. V2 O5 is a promising RMBs cathode material, but its limited interlayer spacing is unfavorable for the rapid diffusion of Mg2+ , demonstrating unsatisfactory electrochemical performance. In this study, the superlattices of V2 O5 and polyaniline (PANI) with expanded interlayer spacing are assembled as the cathode material for RMBs. The intercalation of PANI in the interlayer region of V2 O5 significantly improves the reversible capacities, Mg2+ diffusion kinetics, and cycling performance of the PVO cathode. Furthermore, RMBs with PVO as the cathode and Mg metal as the anode deliver high specific capacities. The introduced polyaniline layer not only expands the interlayer spacing of V2 O5 , but also increases the electrical conductivity. Moreover, ex situ XRD characterization indicates that PVO does not undergo obvious phase transformation with the continuous insertion of Mg2+ , which may be ascribed to the π-conjugated chains of PANI that give flexibility to the structure to improve cycling stability. This study demonstrates that designing organic-inorganic superlattices is an efficient strategy for developing high-performance cathode materials for RMBs.

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