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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.
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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.
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Transtornos Mentais , Saúde Mental , Adolescente , Humanos , Criança , Masculino , Estudos Transversais , Relações Pais-Filho , Poder Familiar/psicologia , Transtornos Mentais/psicologia , PaiRESUMO
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.
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Ipomoea batatas , Amido , Amido/metabolismo , Ipomoea batatas/metabolismo , Secas , Solo , beta-Frutofuranosidase , Glucose-1-Fosfato Adenililtransferase/genética , Glucose-1-Fosfato Adenililtransferase/metabolismo , Sacarose/metabolismoRESUMO
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.
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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/patologiaRESUMO
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).
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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 DNARESUMO
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).
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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 DNARESUMO
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).
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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/análiseRESUMO
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.
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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/etiologiaRESUMO
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.
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BACKGROUND: To the best of our knowledge, although the Chinese version of the Yale Global Tic Severity Scale (YGTSS) is widely used in child psychiatry departments in China, there is very little evidence focusing on the psychometric characteristics of the Chinese version of YGTSS. In this present study, we aim to re-examine the structure of the Chinese version of YGTSS and investigate its reliability and validity. METHODS: A total of 367 children and adolescents with tic disorders aged 5-16 years old participated in the study. The Cronbach's alpha, test-retest reliability and concurrent validity will be calculated. Confirmatory Factor Analysis (CFA) also will be performed to assess the structure of YGTSS. RESULTS: The Cronbach's alpha of the motor tic subscale of YGTSS was 0.84, for the phonic tic subscale of YGTSS, it was 0.90, but for the whole scale, it was 0.58. The test-retest reliability of YGTSS was 0.84. For the results of CFA, the Comparative Fit Index (CFI) of YGTSS based on the Two-Factor Model and Three-Factor Model was 0.97 and 0.96 respectively. The measurement invariance analysis suggested that the Two-Factor model of YGTSS across different age and sex groups was at the accepted level (≥0.90). CONCLUSION: Overall, according to the results of this research, it suggested that the Chinese version of YGTSS showed good psychometric properties. It can be used in the assessment of tic disorders in the Chinese population. In the future, more comprehensive tools for assessing tics need to be further developed, which can cover the symptoms of premonitory urge and tic related obsessive-compulsive symptoms.
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Transtornos de Tique , Tiques , Síndrome de Tourette , Adolescente , Criança , Pré-Escolar , China , Humanos , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Transtornos de Tique/diagnóstico , Síndrome de Tourette/diagnósticoRESUMO
BACKGROUND: Tourette syndrome (TS) is a neurodevelopmental disorder defined by the continual presence of primary motor and vocal tics. Grey matter abnormalities have been identified in numerous studies of TS, but conflicting results have been reported. This study was an unbiased statistical meta-analysis of published neuroimaging studies of TS structures. METHODS: A voxel quantitative meta-analysis technique called activation likelihood estimation (ALE) was used. The meta-analysis included six neuroimaging studies involving 247 TS patients and 236 healthy controls. A statistical threshold of p < 0.05 was established based on the false discovery rate and a cluster extent threshold of 50 voxels. RESULTS: We found that grey matter volumes were significantly increased in the bilateral thalamus, right hypothalamus, right precentral gyrus, left postcentral gyrus, left inferior parietal lobule, right lentiform nucleus, and left insula of TS patients compared to those of healthy controls. In contrast, grey matter volumes were significantly decreased in the bilateral postcentral gyrus, bilateral anterior cingulate, bilateral insula, left posterior cingulate and left postcentral gyrus of TS patients compared to those of healthy controls. CONCLUSIONS: Our present meta-analysis primarily revealed significant increases in grey matter volumes in the thalamus and lentiform nucleus, and decreased grey matter volumes in the anterior cingulate gyrus, of TS patients compared to those in healthy controls. Most of these identified regions are associated with cortico-striato-thalamo-cortical circuits. Further studies with larger sample sizes are needed to confirm these changes in grey matter volumes in TS patients.
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Substância Cinzenta , Síndrome de Tourette , Encéfalo , Substância Cinzenta/diagnóstico por imagem , Giro do Cíngulo , Humanos , Funções Verossimilhança , Imageamento por Ressonância Magnética , Neuroimagem , Síndrome de Tourette/diagnóstico por imagemRESUMO
A field experiment was established to study sweet potato growth, starch dynamic accumulation, key enzymes and gene transcription in the sucrose-to-starch conversion and their relationships under six K2O rates using Ningzishu 1 (sensitive to low-K) and Xushu 32 (tolerant to low-K). The results indicated that K application significantly improved the biomass accumulation of plant and storage root, although treatments at high levels of K, i.e., 300-375 kg K2O ha-1, significantly decreased plant biomass and storage root yield. Compared with the no-K treatment, K application enhanced the biomass accumulation of plant and storage root by 3-47% and 13-45%, respectively, through promoting the biomass accumulation rate. Additionally, K application also enhanced the photosynthetic capacity of sweet potato. In this study, low stomatal conductance and net photosynthetic rate (Pn) accompanied with decreased intercellular CO2 concentration were observed in the no-K treatment at 35 DAT, indicating that Pn was reduced mainly due to stomatal limitation; at 55 DAT, reduced Pn in the no-K treatment was caused by non-stomatal factors. Compared with the no-K treatment, the content of sucrose, amylose and amylopectin decreased by 9-34%, 9-23% and 6-19%, respectively, but starch accumulation increased by 11-21% under K supply. The activities of sucrose synthetase (SuSy), adenosine-diphosphate-glucose pyrophosphorylase (AGPase), starch synthase (SSS) and the transcription of Susy, AGP, SSS34 and SSS67 were enhanced by K application and had positive relationships with starch accumulation. Therefore, K application promoted starch accumulation and storage root yield through regulating the activities and genes transcription of SuSy, AGPase and SSS in the sucrose-to-starch conversion.
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Glucose-1-Fosfato Adenililtransferase/genética , Glucosiltransferases/genética , Raízes de Plantas/crescimento & desenvolvimento , Potássio/farmacologia , Amilopectina/genética , Amilose/genética , Fertilização/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Ipomoea batatas/crescimento & desenvolvimento , Ipomoea batatas/metabolismo , Fotossíntese/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Amido/metabolismo , Sacarose/metabolismoRESUMO
Gene expression analysis is one of the most common and important studies in biology and biomedicine. No matter for traditional blotting analysis or currently commonly used PCR strategy, all need a stable reference gene for normalizing the gene expression. To screen and select housekeeping genes as the most stable reference genes, quantitative real-time PCR (qRT-PCR) was employed to analyze the expression of sixteen commonly used reference genes (IbelF, Ibα-tubulin, IbHIS, IbCOX, IbGAPDH, IbH2B1, IbARF, IbCYC, Ibß-tubulin, IbACT, IbEFl-a, IbG14, IbPLD, IbRPL2, IbUBQ, IbUBI) in five different tissues under two different temperature stresses in sweet potato. Data analysis by the Delta CT, geNorm, NormFinder, and BestKeeper programs revealed that IbelF is the most stable gene and IbUBI is the least stable gene as reference. Our study also shows that combination of two or more genes as reference is a better choice, rendering more substantiated expression data for comparison. This study provides evidence for selecting reference genes in sweet potato gene expression analysis.
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Perfilação da Expressão Gênica/normas , Genes Essenciais , Ipomoea batatas/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Especificidade de Órgãos , Raízes de Plantas/genética , Reação em Cadeia da Polimerase em Tempo Real/normas , Padrões de ReferênciaRESUMO
BACKGROUND: Sweet potato (Ipomoea batatas L.) is the sixth most important food crop in the world. The formation and development of storage roots in sweet potato is a highly complicated and genetically programmed process. However, the underlying mechanisms of storage root development have not yet been elucidated. RESULTS: To better understand the molecular mechanisms involved in storage root development, a combined analysis of the transcriptome and proteome of sweet potato fibrous roots (F) and storage roots at four different stages (D1, D3, D5 and D10) was performed in the present study. A total of 26,273 differentially expressed genes were identified in a comparison between the fibrous root library and four storage root libraries, while 2558 proteins showed a 1.0-fold or greater expression difference as indicated by isobaric tags for relative and absolute quantitation (iTRAQ) analysis. The combination of the transcriptome and proteome analyses and morphological and physiological data revealed several critical pathways involved in storage root formation and development. First, genes/proteins involved in the development of meristems/cambia and starch biosynthesis were all significantly upregulated in storage roots compared with fibrous roots. Second, multiple phytohormones and the genes related to their biosynthesis showed differential expression between fibrous roots and storage roots. Third, a large number of transcription factors were differentially expressed during storage root initiation and development, which suggests the importance of transcription factor regulation in the development of storage roots. Fourth, inconsistent gene expression was found between the transcriptome and proteome data, which indicated posttranscriptional regulatory activity during the development of storage roots. CONCLUSION: Overall, these results reveal multiple events associated with storage root development and provide new insights into the molecular mechanisms underlying the regulatory networks involved in storage root development.
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Regulação da Expressão Gênica de Plantas , Ipomoea batatas/genética , Raízes de Plantas/genética , Proteoma , Amido/biossíntese , Transcriptoma , Redes Reguladoras de Genes , Ipomoea batatas/crescimento & desenvolvimento , Ipomoea batatas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Proteômica , Análise de Sequência de RNARESUMO
The ica operon and aap gene are important factors for Staphylococcus epidermidis biofilm formation. However, we found 15 out of 101 S. epidermidis strains isolated from patients had both the ica operon and the aap gene in the genome but could not form biofilms (ica(+)aap(+)/BF(-) isolates). Compared with standard strain RP62A, the 15 ica(+)aap(+)/BF(-) isolates had similar growth curves and initial attachment abilities, but had much lower apparent transcription levels of the icaA gene and significantly less production of polysaccharide intercellular adhesion (PIA). Furthermore, the expression of accumulation-associated protein in ica(+)aap(+)/BF(-) isolates was much weaker than in RP62A. The mRNA levels of icaADBC transcription-related regulatory genes, including icaR, sarA, rsbU, srrA, arlRS and luxS, were measured in the 15 ica(+)aap(+)/BF(-) clinical isolates. The mRNA levels of arlR and rsbU in all of the ica(+)aap(+)/BF(-) isolates were lower than in RP62A at 4 h. At 10 h, 14/15 of the isolates showed lower mRNA levels of arlR and rsbU than shown by RP62A. However, expression of sarA, luxS, srrA and icaR varied in different ica(+)aap(+)/BF(-) isolates. To further investigate the role of arlRS in biofilm formation, we analyzed icaA, sarA and rsbU transcription, PIA synthesis, Aap expression and biofilm formation in an arlRS deletion mutant of S. epidermidis strain 1457 and all were much less than in the wild type strain. This is consistent with the hypothesis that ArlRS may play an important role in regulating biofilm formation by the ica(+)aap(+)/BF(-)S. epidermidis clinical isolates and operate via both ica-dependent and Aap-dependent pathways.
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Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Óperon , Infecções Estafilocócicas/microbiologia , Staphylococcus epidermidis/genética , Staphylococcus epidermidis/fisiologia , Aderência Bacteriana , Proteínas de Bactérias/genética , Biofilmes/crescimento & desenvolvimento , Deleção de Genes , Perfilação da Expressão Gênica , Hospitais , Humanos , Polissacarídeos Bacterianos/metabolismo , RNA Mensageiro/análise , RNA Mensageiro/genética , Staphylococcus epidermidis/crescimento & desenvolvimento , Staphylococcus epidermidis/isolamento & purificação , Transcrição GênicaRESUMO
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.
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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.
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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/metabolismoRESUMO
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.
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 , PorosidadeRESUMO
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.