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1.
Plant Physiol Biochem ; 212: 108727, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38761548

RESUMO

Phosphatidylserine (PS) is an important lipid signaling required for plant growth regulation and salt stress adaptation. However, how PS positively regulate plant salt tolerance is still largely unknown. In this study, IbPSS1-overexpressed sweetpotato plants that exhibited overproduction of PS was employed to explore the mechanisms underlying the PS stimulation of plant salt tolerance. The results revealed that the IbPSS1-overexpressed sweetpotato accumulated less Na+ in the stem and leaf tissues compared with the wild type plants. Proteomic profile of roots showed that lignin synthesis-related proteins over-accumulated in IbPSS1-overexpressed sweetpotato. Correspondingly, the lignin content was enhanced but the influx of Na + into the stele was significantly blocked in IbPSS1-overexpressed sweetpotato. The results further revealed that ethylene synthesis and signaling related genes were upregulated in IbPSS1-overexpressed sweetpotato. Ethylene imaging experiment revealed the enhancement of ethylene mainly localized in the root stele. Inhibition of ethylene synthesis completely reversed the PS-overproduction induced lignin synthesis and Na+ influx pattern in stele tissues. Taken together, our findings demonstrate a mechanism by which PS regulates ethylene signaling and lignin synthesis in the root stele, thus helping sweetpotato plants to block the loading of Na+ into the xylem and to minimize the accumulation of Na+ in the shoots.


Assuntos
Etilenos , Ipomoea batatas , Lignina , Proteínas de Plantas , Raízes de Plantas , Tolerância ao Sal , Transdução de Sinais , Etilenos/metabolismo , Etilenos/biossíntese , Lignina/metabolismo , Lignina/biossíntese , Ipomoea batatas/genética , Ipomoea batatas/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Tolerância ao Sal/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas , Fosfatidilserinas/metabolismo , Sódio/metabolismo
2.
Proc Natl Acad Sci U S A ; 121(22): e2308414121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38768343

RESUMO

The complex sequential response of frustrated materials results from the interactions between material bits called hysterons. Hence, a central challenge is to understand and control these interactions, so that materials with targeted pathways and functionalities can be realized. Here, we show that hysterons in serial configurations experience geometrically controllable antiferromagnetic-like interactions. We create hysteron-based metamaterials that leverage these interactions to realize targeted pathways, including those that break the return point memory property, characteristic of independent or weakly interacting hysterons. We uncover that the complex response to sequential driving of such strongly interacting hysteron-based materials can be described by finite state machines. We realize information processing operations such as string parsing in materia, and outline a general framework to uncover and characterize the FSMs for a given physical system. Our work provides a general strategy to understand and control hysteron interactions, and opens a broad avenue toward material-based information processing.

3.
ACS Appl Mater Interfaces ; 16(7): 9247-9254, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38349048

RESUMO

Rendering invisibility in the wide application scenarios has seen a surge in interest in recent years. Though various approaches have been proposed to realize concealments under different conditions, achieving polarization-independent invisibility for large objects remains a big challenge. Here, we propose to attain invisibility of a large dielectric slab with polarization constraints being totally lifted. This is accomplished by employing an antiscattering coating made of anisotropic metamaterials. We show that by tailoring the electric resonance of a triangular mushroom structure, antiphase electric dipole moment can be induced, resulting in an antipolarization response of the whole metamaterial coatings. By putting the proposed coatings on both sides of a large dielectric slab, a neutralization effect of the total polarization is observed, leading to the peculiar phenomenon of full-polarization invisibility. Our results are validated through full-wave simulations and experimental measurements. Remarkably, the intrinsic null-polarization property of the coating-slab-coating structure guarantees the invisibility feature of a large-scale bulk made by simply stacking the sandwiched composites, which facilitates the application of invisibility in practical scenarios such as the invisibility cloaks and the reflectionless antenna radomes.

4.
Int J Mol Sci ; 24(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36769375

RESUMO

In this study, the influences of long-term soil drought with three levels [soil-relative water content (SRWC) (75 ± 5)%, as the control; SRWC (55 ± 5)%, mild drought; SRWC (45 ± 5)%, severe drought] were investigated on sucrose-starch metabolism in sweet potato tuberous roots (TRs) by pot experiment. Compared to the control, drought stress increased soluble sugar and sucrose content by 4-60% and 9-75%, respectively, but reduced starch accumulation by 30-66% through decreasing the starch accumulate rate in TRs. In the drought-treated TRs, the inhibition of sucrose decomposition was attributed to the reduced activities of acid invertase (AI) and alkaline invertase (AKI) and the IbA-INV3 expression, rather than sucrose synthase (SuSy), consequently leading to the increased sucrose content in TRs. In addition, starch synthesis was inhibited mainly by reducing ADP-glucose pyrophosphorylase (AGPase), granular starch synthase (GBSS) and starch branching enzyme (SBE) activities in TRs under drought stress, and AGPase was the rate-limiting enzyme. Furthermore, soil drought remarkably up-regulated the IbSWEET11, IbSWEET605, and IbSUT4 expressions in Jishu 26 TRs, while it down-regulated or had no significant differences in Xushu 32 and Ningzishu 1 TRs. These results suggested that the sucrose-loading capability in Jishu 26 TRs were stronger than that in Xushu 32 and Ningzishu 1 TRs. Moreover, IbA-INV3, IbAGPS1, IbAGPS2, IbGBSSI and IbSBEII play important roles in different drought-tolerant cultivars under drought stress.


Assuntos
Ipomoea batatas , Amido , Amido/metabolismo , Ipomoea batatas/metabolismo , Secas , Solo , beta-Frutofuranosidase , Glucose-1-Fosfato Adenililtransferase/genética , Glucose-1-Fosfato Adenililtransferase/metabolismo , Sacarose/metabolismo
5.
Pediatr Res ; 93(5): 1432-1438, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927576

RESUMO

BACKGROUND: Life events and parenting styles might play an important role in children's mental health. AIMS: This study aims to explore how life events and parenting styles influence children's mental health based on a Chinese sample. METHODS: A total of 3535 participants had at least one mental disorder (positive group), while a total of 3561 participants had no mental disorders (negative group). The Child Behavior Checklist (CBCL), Adolescent Self-Rating Life Events Check List (ASLEC) and Egna Minnen Beträffande Uppfostran (EMBU) were used for screening these two groups. RESULTS: CBCL total scores differed significantly by sex in the Positive group according to the Mann-Whitney tests (Z = -5.40, p < 0.001). Multiple regression analyses showed that the dimensions of punishment (p = 0.014) and other (p = 0.048) in the ASLEC scale can significantly predict CBCL total scores in the Positive group. Sex, age and overprotection from the father were risk factors (p < 0.001) according to binary logistic regression. CONCLUSIONS: Life events and parenting styles may have impacts on mental health. Fathers play a very important role in children's growth. Punitive education and fathers' overprotection might be risk factors for children's mental health. IMPACT: It is a large sample (3535) study of Chinese children and adolescents It provides evidence that life events and parenting styles have impacts on mental health and that fathers play a very important role in children's growth. It is conducive to the development of interventions for the mental health of children and adolescents.


Assuntos
Transtornos Mentais , Saúde Mental , Adolescente , Humanos , Criança , Masculino , Estudos Transversais , Relações Pais-Filho , Poder Familiar/psicologia , Transtornos Mentais/psicologia , Pai
6.
Curr Microbiol ; 80(1): 34, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36508041

RESUMO

A Gram-negative, facultative anaerobic bacterial strain, designated YIM B02556T, was isolated from the root of Paris polyphylla Smith var. yunnanensis collected from Yunnan Province, southwest China. By using a polyphasic approach, its taxonomic position was investigated. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain YIM B02556T belonged to the genus Azospirillum and the 16S rRNA gene sequence similarity values of strain YIM B02556T to the type strains of members of this genus ranged from 94.9 to 98.3%. Overall genome relatedness index (OGRI) analysis estimated based on average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) between YIM B02556T and other Azospirillum species type strains were <90.8% and <37.8%, lower than the limit of species circumscription. Cells of the strain were characterized as oxidase- and catalase-positive, with motility provided by flagella. The growth conditions of the strain were found to occur at 20-40 °C (optimum, 35 °C), and pH 6.0-9.5 (optimum, pH 7.5). Strain YIM B02556T can tolerate 2% NaCl concentration. Strain YIM B02556T contained Q-10 as the major ubiquinone. The major fatty acids were C18:1 ω7c and summed feature three (C16:1 ω7c and/or C16:1 ω6c). The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, and phosphatidylethanolamine. Based on polyphasic analysis, strain YIM B02556T could be differentiated genotypically and phenotypically from recognized species of the genus Azospirillum. Therefore, the isolate represents a novel species, for which the name Azospirillum endophyticum is proposed. The type strain is YIM B02556T (=JCM 34631T=CGMCC 1.18654T).


Assuntos
Azospirillum , RNA Ribossômico 16S/genética , Azospirillum/genética , Filogenia , Endófitos/genética , Composição de Bases , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , Fosfolipídeos/análise , China , Ácidos Graxos/análise
7.
Front Plant Sci ; 13: 1069181, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36561445

RESUMO

In order to explore the effect of potassium (K) deficiency on nitrogen (N) metabolism in sweet potato (Ipomoea batatas L.), a hydroponic experiment was conducted with two genotypes (Xushu 32, low-K-tolerant; Ningzishu 1, low-K-sensitive) under two K treatments (-K, <0.03 mM of K+; +K, 5 mM of K+) in the greenhouse of Jiangsu Normal University. The results showed that K deficiency decreased root, stem, and leaf biomass by 13%-58% and reduced whole plant biomass by 24%-35%. Compared to +K, the amount of K and K accumulation in sweet potato leaves and roots was significantly decreased by increasing root K+ efflux in K-deficiency-treated plants. In addition, leaf K, N, ammonium nitrogen (NH4 +-N), or nitrate nitrogen (NO3 --N) in leaves and roots significantly reduced under K deficiency, and leaf K content had a significant quadratic relationship with soluble protein, NO3 --N, or NH4 +-N in leaves and roots. Under K deficiency, higher glutamate synthase (GOGAT) activity did not increase amino acid synthesis in roots; however, the range of variation in leaves was larger than that in roots with increased amino acid in roots, indicating that the transformation of amino acids into proteins in roots and the amino acid export from roots to leaves were not inhibited. K deficiency decreased the activity of nitrate reductase (NR) and nitrite reductase (NiR), even if the transcription level of NR and NiR increased, decreased, or remained unchanged. The NO3 -/NH4 + ratio in leaves and roots under K deficiency decreased, except in Ningzishu 1 leaves. These results indicated that for Ningzishu 1, more NO3 - was stored under K deficiency in leaves, and the NR and NiR determined the response to K deficiency in leaves. Therefore, the resistance of NR and NiR activities to K deficiency may be a dominant factor that ameliorates the growth between Xushu 32 and Ningzishu 1 with different low-K sensitivities.

8.
J Integr Neurosci ; 21(6): 172, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36424736

RESUMO

Repetitive transcranial megnetic stimulation (rTMS) has been widely used in patients with psychiatric disorders. Previous studies revealed good efficacy of rTMS for patients with obsession-compulsive disorder (OCD) and Tic disorder (TD). OCD and TD are closely related and considered to etiologically overlap. Patients with the co-occurrence of OCD and TD are often identified. Therefore, we conducted a quick review of rTMS for the treatment of these two diseases to compare the similarities and differences of rTMS for OCD and TD, which might provide an indication for the treatment of the co-occurrence of OCD and TD. We searched articles published in PubMed, Wanfang, and Web of Science from January 2001 to January 2022. Both inclusion criteria and exclusion criteria were developed to identify the relevant included studies. Data on the frequency, target area, sample size, and number of males, especially the rTMS treatment procedure or parameters, were extracted in the included studies. We included 26 studies on OCD and 12 studies on TD in this quick review. A total of 996 participants were included. Based on the review of the included studies, lowfrequency rTMS might be used more than high-frequency rTMS, and the supplementary motor area (SMA) might show better efficacy than the dorsolateral prefrontal cortex (DLPFC) in OCD. For patients with TD, low-frequency rTMS located in the SMA might show good efficacy both in OCD and TD. Our quick review elaborated the treatment efficacy of rTMS for both patients with OCD and those with TD. It seems that the SMA is an important target choice for both OCD and TD patients. Low-frequency rTMS might be used more than high-frequency rTMS in both OCD and TD patients. In future studies, we should explore more about the efficacy of rTMS for patients with co-occurring OCD and TD, especially for the efficacy of targeted SMA with low frequency.


Assuntos
Córtex Motor , Transtorno Obsessivo-Compulsivo , Transtornos de Tique , Masculino , Humanos , Estimulação Magnética Transcraniana/métodos , Transtorno Obsessivo-Compulsivo/terapia , Transtorno Obsessivo-Compulsivo/etiologia , Transtorno Obsessivo-Compulsivo/psicologia , Resultado do Tratamento , Transtornos de Tique/terapia , Transtornos de Tique/etiologia
9.
Molecules ; 27(12)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35744866

RESUMO

By performing first-principles calculations, we studied hexagonal-boron-nitride (hBN)-supported graphene, in which moiré structures are formed due to lattice mismatch or interlayer rotation. A series of graphene/hBN systems has been studied to reveal the evolution of properties with respect to different twisting angles (21.78°, 13.1°, 9.43°, 7.34°, 5.1°, and 3.48°). Although AA- and AB-stacked graphene/hBN are gapped at the Dirac point by about 50 meV, the energy gap of the moiré graphene/hBN, which is much more asymmetric, is only about several meV. Although the Dirac cone of graphene residing in the wide gap of hBN is not much affected, the calculated Fermi velocity is found to decrease with the increase in the moiré super lattice constant due to charge transfer. The periodic potential imposed by hBN modulated charge distributions in graphene, leading to the shift of graphene bands. In agreement with experiments, there are dips in the calculated density of states, which get closer and closer to the Fermi energy as the moiré lattice grows larger.

10.
Brain Sci ; 12(5)2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35625036

RESUMO

Background: Obsessive-compulsive disorder (OCD) and tic disorders (TDs) are closely related and considered to etiologically overlap. Both disorders are characterized by repetitive behaviors. TD and OCD often co-occur. The high comorbidity between OCD and TD individuals suggests that we also need to pay more attention to the homogeneity and heterogeneity between TS and OCD. To date, there has been no systematic nationwide epidemiological survey of the mental health (including tic disorders and obsessive-compulsive disorder) of children and adolescents in China. Methods: A two-stage epidemiological study of psychiatric point prevalence was conducted. We used the multistage cluster stratified random sampling strategy to assess five provinces of China. The Child Behavior Checklist was used to identify behavioral problems among the enrolled students in the first stage. The results from the Mini-International Neuropsychiatric Interview for Children and Adolescents and evaluations from two psychiatrists based on the Diagnostic and Statistical Manual-IV were used to make a diagnosis. Point weighted prevalence for TD and OCD was estimated. We adjusted prevalence estimates with the product of sampling weights and poststratification weights. Standard error values and 95% confidential intervals were generated with Taylor series linearization. Rao−Scott adjusted chi-square (χ2) tests were employed to compare the prevalence estimates of different age and sex groups. Results: In the first stage, 73,992 participants aged 6−16 years old were selected. The prevalence rates of OCD and TDs were 1.37% (95% CI: 1.28−1.45) and 2.46% (95% CI: 2.35−2.57), respectively. The prevalence of OCD was found to be higher in girls (p < 0.001) and higher in boys with transient tic disorder (TTD) (p < 0.001) and Tourette's syndrome (TS) (p < 0.001). The most common comorbidity of TS was OCD (40.73%), and for OCD, it was TS (11.36%). Conclusions: Our study is the first nationwide survey on the prevalence of TD (2.46%) and OCD (1.37%) in school students aged 6−16 years old in China. The high comorbidity between OCD and TD individuals suggested overlap based on the prevalence dimensions, which might be influenced by age and sex. This result suggested that we also need to pay more attention to the homogeneity and heterogeneity between TS and OCD.

11.
Haemophilia ; 28(4): 578-587, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35505587

RESUMO

INTRODUCTION: Microstructural alterations of brain structure in haemophilic boys were found in our previous study. AIM: We investigated alterations of brain function in school-age boys with severe haemophilia A (HA) with resting-state functional magnetic resonance imaging (rs-fMRI). METHODS: We obtained rs-fMRI scans from 24 boys with HA and 25 demographically matched healthy children. Spontaneous brain activity parameters were calculated. Graph theoretical analyses on rs-fMRI data at the global and regional levels were performed. Two-sample t tests were used to analyze differences, and correlation analyses identified relationships between altered neural properties and psychological characteristics. RESULTS: Children with severe HA showed small-worldness organization but with an increased efficiency and compactness in functional segregation. The whole brain showed an overtight connection pattern. At the regional level, significantly increased nodal efficiency in the salience network (SN), default mode network (DMN) and executive control network was found. Social Anxiety Scale for Children (SASC) scores were positively correlated with these alterations. Spontaneous brain activity alterations in regions including the cerebellum, frontal gyrus (orbital part), temporal gyrus and thalamus were observed; some of these regions have been closely related to social anxiety and family or social support. CONCLUSION: Our study is the first to evaluate the neurological functional changes in school-age boys with severe HA. Disruptions in topographic characteristics and abnormal activity were closely related to social conditions. These data could help us to understand early neurological alterations in haemophilic children, improve the traditional view of family support and strengthen normal school life at an early stage.


Assuntos
Mapeamento Encefálico , Hemofilia A , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Criança , Hemofilia A/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/patologia
12.
BMJ Open ; 12(5): e047343, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35577466

RESUMO

INTRODUCTION: Tic disorder (TD) is a common neurodevelopmental disorder in children, and it can be categorised into three subtypes: provisional tic disorder (PTD), chronic motor or vocal TD (CMT or CVT), and Tourette syndrome (TS). An early diagnostic classification among these subtypes is not possible based on a new-onset tic symptom. Machine learning tools have been widely used for early diagnostic classification based on functional MRI (fMRI). However, few machine learning models have been built for the diagnostic classification of patients with TD. Therefore, in the present study, we will provide a study protocol that uses the machine learning model to make early classifications of the three different types of TD. METHODS AND ANALYSIS: We planned to recruit 200 children aged 6-9 years with new-onset tic symptoms and 100 age-matched and sex-matched healthy controls under resting-state MRI scanning. Based on the neuroimaging data of resting-state fMRI, the support vector machine (SVM) model will be built. We planned to construct an SVM model based on functional connectivity for the early diagnosis classification of TD subtypes (including PTD, CMT/CVT, TS). ETHICS AND DISSEMINATION: This study was approved by the ethics committee of Beijing Children's Hospital. The trial results will be submitted to peer-reviewed journals for publication. TRIAL REGISTRATION NUMBER: ChiCTR2000033257.


Assuntos
Transtornos de Tique , Tiques , Síndrome de Tourette , Criança , Humanos , Aprendizado de Máquina , Imageamento por Ressonância Magnética , Transtornos de Tique/diagnóstico por imagem , Síndrome de Tourette/diagnóstico por imagem
13.
Transl Pediatr ; 11(3): 349-358, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35378963

RESUMO

Background: Autism spectrum disorder is characterized by atypical developmental changes during brain maturation, but regional brain functional changes that occur with age and across different frequency bands are unknown. Therefore, the current study aimed to explore potential age and frequency band-related changes in the regional brain activities in autism. Methods: A total of 65 participants who met the DSM-IV criteria for autistic disorder and 55 typically developed (TD) participants (both age 6-30 years) were recruited in the current study. The two groups were matched in age (t=-1.314, P=0.191) and gender (χ2=2.760, P=0.097). The amplitude of low-frequency fluctuations (ALFF) was employed to explore the effect of development on spontaneous brain activity in individuals with autism and in TD participants across slow-5 (0.01-0.027 Hz), slow-4 (0.027-0.073 Hz), and slow-3 (0.073-0.1 Hz) frequency bands. The diagnosis-by-age interaction effect in the whole brain voxels in autism and TD groups was investigated. Results: Autism individuals showed significantly higher ALFF in the dorsal striatum in childhood (Caudate cluster: t=3.626, P=0.001; Putamen cluster: t=2.839, P=0.007) and remarkably lower ALFF in the dorsal striatum in adulthood (Caudate cluster: t=-2.198, P=0.038; Putamen cluster: t=-2.314, P=0.030) relative to TD, while no significant differences were observed in adolescence (all P>0.05). In addition, abnormal ALFF amplitudes were specific to the slow-4 (0.027-0.073 Hz) frequency band in the clusters above. Conclusions: The current study indicated abnormal development patterns in the spontaneous activity of the dorsal striatum in autism and highlighted the potential role of the slow-4 frequency band in the pathology of autism. Also, the potential brain mechanism of autism was revealed, suggesting that autism-related variations should be investigated in a specific frequency.

14.
Front Psychiatry ; 13: 785547, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35308883

RESUMO

Objective: The aim of this study is comparing gray matter alterations in SCZ pediatric patients with those suffering from obsessive-compulsive disorder (OCD) based on a systematic review and an activation likelihood estimation (ALE) meta-analysis. Methods: A systematic literature search was performed in PubMed, Elsevier, and China National Knowledge Infrastructure (CNKI). A systematic review and an ALE meta-analysis were performed to quantitatively examine brain gray matter alterations. Results: Children and adolescents with schizophrenia had decreased gray matter volume (GMV) mainly in the prefrontal cortex (PFC), temporal cortex (such as the middle temporal gyrus and transverse temporal gyrus), and insula, while children and adolescents with OCD mainly had increased GMV in the PFC and the striatum (including the lentiform nucleus and caudate nucleus), and decreased GMV in the parietal cortex. Conclusions: Our results suggest that gray matter abnormalities in the PFC may indicate homogeneity between the two diseases. In children and adolescents, structural alterations in schizophrenia mainly involve the fronto-temporal and cortico-insula circuits, whereas those in OCD mainly involve the prefrontal-parietal and the prefrontal-striatal circuits.

15.
ACS Appl Mater Interfaces ; 14(8): 10712-10720, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35171564

RESUMO

Hierarchically porous metal-organic frameworks (HP-MOFs) are promising in many applications. However, most previous studies focus on HP-MOFs with two kinds of pore structures. Herein, a strategy for efficient construction of HP-MOFs possessing macro-meso-micropores using template-assisted spray drying followed by etching process is proposed. Taking ZIF-8 as an example, using polystyrene (PS) templates, the complete HP-ZIF-8 with all the three categories of pores can be easily fabricated. The close arrangement of intrinsic microporous nanosized ZIF-8 (N-ZIF-8) in the spray drying process results in the creation of mesopores, while the macropores are further generated after the removal of PS templates. The structures of macropores and mesopores can be easily adjusted by altering the size and proportion of PS and the size of N-ZIF-8, respectively. Furthermore, this method is extended to the preparation of HP-HKUST-1. As a proof-of-concept, HP-ZIF-8 displays excellent catalytic properties in Knoevenagel reaction owing to its unique pore features. Compared with conventional microsized ZIF-8 (M-ZIF-8) with similar size, HP-ZIF-8 achieves the significantly increased conversion of benzaldehyde from 55% to 100% within 3 h, and shows better recycling performance than N-ZIF-8.

16.
Nanoscale ; 14(7): 2793-2801, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35133372

RESUMO

The intrinsic properties and structure of carrier materials, as well as the drug-loading method, are crucial to the fabrication of high-performance controlled drug release systems. Metal-organic frameworks (MOFs) have attracted great attention in drug delivery due to their rich variety and very precisely designable structures, but their inherent small pores limit their application towards large-size drug molecules. Herein, we report a facile and efficient approach for the construction of hierarchically porous ZIF-8 (HP-ZIF-8) by spray drying. The homogeneously distributed mesopores, which result from the interspaces in the closely arranged nanosized ZIF-8 (N-ZIF-8), can be tuned by adjusting the primary particle size. More importantly, a drug (doxorubicin (DOX), for example) can be simultaneously encapsulated during the fabrication process of HP-ZIF-8, achieving a high loading rate of 79% and an encapsulation efficiency of 79%. Furthermore, we demonstrate that the obtained DOX@HP-ZIF-8 is a pH-responsive system and the release can also be controlled by the mesopore size. Although HP-ZIF-8 shows obvious advantages in drug loading and release performance compared with N-ZIF-8 loaded with DOX by the same solvent adsorption approach, DOX@HP-ZIF-8 displays significantly increased loading capacity (more than 3 times) and the slowest release rate due to its drug-loading method. Their therapeutic efficacy on HeLa cells has also been proved. These findings have important implications for the construction of HP-MOFs as drug carriers and will also present a new platform for controlled drug release and biomedical applications.


Assuntos
Sistemas de Liberação de Medicamentos , Secagem por Atomização , Preparações de Ação Retardada , Doxorrubicina/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Células HeLa , Humanos , Porosidade
17.
Artigo em Inglês | MEDLINE | ID: mdl-35101065

RESUMO

BACKGROUND: Structural magnetic resonance imaging (sMRI) studies have shown atypicalities in structural brain changes in individuals with autism spectrum disorder (ASD), while a noticeable discrepancy in their results indicates the necessity of conducting further researches. METHODS: The current study investigated the atypical structural brain features of autistic individuals who aged 6-30 years old. A total of 52 autistic individuals and 50 age-, gender-, and intelligence quotient (IQ)-matched typically developing (TD) individuals were included in this study, and were assigned into three based cohorts: childhood (6-12 years old), adolescence (13-18 years old), and adulthood (19-30 years old). Analyses of whole-brain volume and voxel-based morphometry (VBM) on the sMRI data were conducted. RESULTS: No significant difference was found in the volumes of whole-brain, gray matter, and white matter between the autism and TD groups in the three age-based cohorts. For VBM analyses, the volumes of gray matter in the right superior temporal gyrus and right inferior parietal lobule in the autism group (6-12 years old) were smaller than those in the TD group; the gray matter volume in the left inferior parietal lobule in the autism group (13-18 years old) was larger than that in the TD group; the gray matter volume in the right middle occipital gyrus in the autism group (19-30 years old) was larger than that in the TD group, and the gray matter volume in the left posterior cingulate gyrus in the autism group was smaller than that in the TD group. CONCLUSION: Autistic individuals showed different atypical regional gray matter volumetric changes in childhood, adolescence, and adulthood compared to their TD peers, indicating that it is essential to consider developmental stages of the brain when exploring brain structural atypicalities in autism.

18.
Curr Microbiol ; 79(2): 52, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34982259

RESUMO

A novel endophytic actinobacterium, designated as strain YIM B02568T, was isolated from the root of Paris polyphylla Smith var. Yunnanensis obtained from Yunnan Province, southwest China. Strain YIM B02568T was characterized using a polyphasic approach. Phylogenetic analysis indicated that this isolate belonged to the genus Janibacter. The 16S rRNA gene sequence similarity values of strain YIM B02568T to the type strains of members of this genus ranged from 95.8 to 98.6%. However, overall genome relatedness indices were significantly lower than the widely accepted species-defined threshold. The cell wall of strain YIM B02568T contained meso-diaminopimelic acid. The major menaquinone was MK-8(H4). The main polar lipids were phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylinositol. The major cellular fatty acids were comprised of iso-C16:0 and C18:1 ω9c. The DNA G + C content was 71.6 mol%. Based on the data from the polyphasic studies, we propose that strain YIM B02568T represents a novel species within the genus Janibacter, Janibacter endophyticus sp. nov. The type strain is YIM B02568T (= JCM 34639T = CGMCC 1.18658T).


Assuntos
Liliaceae , Fosfolipídeos , Técnicas de Tipagem Bacteriana , China , DNA Bacteriano/genética , Ácidos Graxos/análise , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
19.
Arch Microbiol ; 204(2): 129, 2022 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-34999970

RESUMO

A novel endophytic strain, designated YIM B02564T, was isolated from the root of Paris polyphylla Smith var. yunnanensis obtained from Yunnan Province, southwest China. By using a polyphasic approach, cells of the strain were characterized as facultative anaerobic, Gram-positive and rod-shaped. The growth conditions of the strain were found to occur at 20-55 °C (optimum, 30 °C), pH 6.0-9.0 (optimum, pH 7.0). Strain YIM B02564T can tolerate 2% NaCl concentration. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain YIM B02564T belonged to the genus Neobacillus and the 16S rRNA gene sequence similarity values of strain YIM B02564T to the type strains of members of this genus ranged from 95.6 to 97.8%. The DNA G+C content of strain YIM B02564T calculated from the whole genome sequence was 41.6 mol%. Values of the ANI and the dDDH between strain YIM B02564T and its closely related Neobacillus species were below 77.9% and 21.5%. Strain YIM B02564T contained MK-7 as the major menaquinone, iso-C15:0 and anteiso-C15:0 as the major fatty acids. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unidentified aminophospholipid and four unidentified lipids. It contained meso-diaminopimelic acid in the cell-wall peptidoglycan. On the basis of polyphasic analysis, strain YIM B02564T could be differentiated genotypically and phenotypically from recognized species of the genus Neobacillus. The isolate therefore represents a novel species, for which the name Neobacillus paridis is proposed. The type strain is YIM B02564T (= JCM 34668T = CGMCC 1.18655T).


Assuntos
Endófitos , Liliaceae , Técnicas de Tipagem Bacteriana , China , DNA Bacteriano/genética , Endófitos/genética , Ácidos Graxos/análise , Hibridização de Ácido Nucleico , Fosfolipídeos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
20.
Autism ; 26(5): 1108-1122, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34465247

RESUMO

LAY ABSTRACT: Autism spectrum disorder has long been conceptualized as a disorder of "atypical development of functional brain connectivity (which refers to correlations in activity levels of distant brain regions)." However, most of the research has focused on the connectivity between cortical regions, and much remains unknown about the developmental changes of functional connectivity between subcortical and cortical areas in autism spectrum disorder. We used the technique of resting-state functional magnetic resonance imaging to explore the developmental characteristics of intrinsic functional connectivity (functional brain connectivity when people are asked not to do anything) between subcortical and cortical regions in individuals with and without autism spectrum disorder aged 6-30 years. We focused on one important subcortical structure called striatum, which has roles in motor, cognitive, and affective processes. We found that cortico-striatal intrinsic functional connectivities showed opposite developmental trajectories in autism spectrum disorder and typically developing individuals, with connectivity increasing with age in autism spectrum disorder and decreasing or constant in typically developing individuals. We also found significant negative behavioral correlations between those atypical cortico-striatal intrinsic functional connectivities and autistic symptoms, such as social-communication deficits, and restricted/repetitive behaviors and interests. Taken together, this work highlights that the atypical development of cortico-subcortical functional connectivity might be largely involved in the neuropathological mechanisms of autism spectrum disorder.


Assuntos
Transtorno do Espectro Autista , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo , Mapeamento Encefálico/métodos , Cognição , Humanos , Imageamento por Ressonância Magnética/métodos , Vias Neurais/diagnóstico por imagem
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