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1.
Arch Virol ; 169(8): 162, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985350

RESUMO

Using a high-throughput sequencing (HTS) approach, we report the discovery of a new alphasatellite identified in a winter barley plant collected in France in 2022 that was also infected by wheat dwarf virus (WDV). The presence of the satellite and of WDV was confirmed by several independent PCR assays, and the complete genome sequence was determined. The circular satellite genome is 1424 nt long and shows typical hallmarks of members of the subfamily Geminialphasatellitinae, including a replication-associated hairpin with a CAGTATTAC sequence and a Rep-encoding open reading frame (ORF). It also possesses a second ORF, embedded in a different frame within the Rep ORF, which is also observed in clecrusatellites and a few other members of the family Alphasatellitidae. Pairwise sequence comparisons and phylogenetic analysis showed that this satellite represents a novel species. Its closest relatives are in the genus Colecusatellite, but it likely represents a new genus given its divergence from other genera of the subfamily Geminialphasatellitinae. Given that WDV was the only virus observed in coinfection with the satellite, the name "wheat dwarf virus-associated alphasatellite" is proposed for this novel agent.


Assuntos
Genoma Viral , Hordeum , Fases de Leitura Aberta , Filogenia , Doenças das Plantas , França , Hordeum/virologia , Doenças das Plantas/virologia , Genoma Viral/genética , Geminiviridae/genética , Geminiviridae/classificação , Geminiviridae/isolamento & purificação , Vírus Satélites/genética , Vírus Satélites/classificação , Vírus Satélites/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala
2.
J Insect Sci ; 24(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38195069

RESUMO

The Asian citrus psyllid (ACP) is the main vector of Citrus Huanglongbing, the most damaging citrus disease, causing significant financial losses in the citrus industry. Global warming has expanded the habitat of this pest, allowing it to continue its northward migration to China. Population genetic information of ACP is fundamentally essential for species management. This study investigated the genetic diversity and population structure of Chinese ACP using the mitochondrial cytochrome oxidase subunit I gene by dataset comprised 721 sequences from 27 geographic sites in China. Low haplotype diversity (0.323 ±â€…0.022) and low nucleotide diversity (0.00071 ±â€…0.00007) were observed in the entire population, which may indicate recent founder events. Twenty-three haplotypes were identified and clustered into 2 haplogroups: haplogroup I and haplogroup II. Haplogroup II included only 2 unique haplotypes, which occurred exclusively in the Southwest China ACP population. Genetic differentiation analyses were also indicative of Southwest China population was significantly differentiated from the remaining populations. Demographic history analysis showed that ACP population in China has experienced demographic expansion. Our results provided a better understanding of the genetic distribution patterns and structures of ACP populations in China.


Assuntos
Citrus , Hemípteros , Animais , Hemípteros/genética , China , Citrus/genética , Variação Genética
3.
Nat Mater ; 21(11): 1258-1262, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36109672

RESUMO

Titanium alloys, widely used in the aerospace, automotive and energy sectors, require complex casting and thermomechanical processing to achieve the high strengths required for load-bearing applications. Here we reveal that additive manufacturing can exploit thermal cycling and rapid solidification to create ultrastrong and thermally stable titanium alloys, which may be directly implemented in service. As demonstrated in a commercial titanium alloy, after simple post-heat treatment, adequate elongation and tensile strengths over 1,600 MPa are achieved. The excellent properties are attributed to the unusual formation of dense, stable and internally twinned nanoprecipitates, which are rarely observed in traditionally processed titanium alloys. These nanotwinned precipitates are shown to originate from a high density of dislocations with a dominant screw character and formed from the additive manufacturing process. The work here paves the way to fabricate structural materials with unique microstructures and excellent properties for broad applications.

4.
Curr Issues Mol Biol ; 45(1): 122-133, 2022 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-36661495

RESUMO

Sweet orange (Citrus sinensis) is a sub-tropical fruit crop with important economic value that is popular worldwide; however, various pathogens significantly affect citrus cultivation and distribution. AlkB homolog (ALKBH) proteins play crucial roles in RNA metabolism and translation in plants; however, no systematic investigations have been performed on ALKBH in sweet oranges. In this study, ten ALKBH gene family members were identified in Citrus sinensis genome. Standardized analyses, including physical properties, phylogenetic analysis, gene structure, motif composition, cis-acting element prediction, chromosome distribution, and synteny analysis, were conducted. The phylogenetic analysis suggested that the ten proteins were clustered into three groups, each of which had similar motifs and gene structures. Gene expression profiling revealed that almost all CsALKBH proteins were highly expressed in callus, and ALKBH9/10-like group members responded positively to biotic stress. Overall, this study is the first to report a genome-wide assessment of the ALKBH family in sweet oranges and provides valuable insights for candidate gene selection and elucidating the molecular mechanism of sweet orange response to pathogenic infections.

5.
Chemistry ; 28(28): e202200019, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35266216

RESUMO

Transition metal Fe, Co, Ni and Cu doped strontium titanate-rich SrTiO3 @TiO2 (STO@T) materials were prepared by hydrothermal method. The prepared doped materials exhibit better photocatalytic CO2 reduction to CH4 ability under visible light conditions. Among them, Fe-doped and undoped SrTiO3 @TiO2 under visible light conditions CO2 reduction products only CO, while M-STO@T (M=Co, Ni, Cu) samples converted CO2 to CH4 . The average methane yield of Ni-doped STO@T samples are as high as 73.85 µmol g-1 h-1 . The production of methane is mainly due to the increase in the response of the doped samples to visible light. And the increase in the separation rate of photogenerated electrons and holes and the efficiency of electron transport caused by the generation of impurity levels. The impurity level caused by Ti3+ plays an important role in the production of methane by CO2 visible light reduction. Ni doping effectively improves the photocatalytic performance of STO@T and CO2 reduction mechanism were explained.

6.
Phytopathology ; 111(1): 227-236, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32648524

RESUMO

Seven isolates of a putative cytorhabdovirus (family Rhabdoviridae, order Mononegavirales) designated as citrus-associated rhabdovirus (CiaRV) were identified in citrus, passion fruit, and paper bush from the same geographical area in China. CiaRV, bean-associated cytorhabdovirus (Brazil), and papaya virus E (Ecuador) should be taxonomically classified in the species Papaya cytorhabdovirus. Due to natural mutations, the glycoprotein (G) and P4 genes were impaired in citrus-infecting isolates of CiaRV, resulting in an atypical rhabdovirus genome organization of 3' leader-N-P-P3-M-L-5' trailer. The P3 protein of CiaRV shared a common origin with begomoviral movement proteins (family Geminiviridae). Secondary structure analysis and trans-complementation of movement-deficient tomato mosaic virus and potato virus X mutants by CiaRV P3 supported its function in viral cell-to-cell trafficking. The wide geographical dispersal of CiaRV and related viruses suggests an efficient transmission mechanism, as well as an underlying risk to global agriculture. Both the natural phenomenon and experimental analyses demonstrated presence of the "degraded" type of CiaRV in citrus, in parallel to "undegraded" types in other host plant species. This case study shows a plant virus losing the function of an important but nonessential gene, likely due to host shift and adaption, which deepened our understanding of course of natural viral diversification.


Assuntos
Vírus de Plantas , Rhabdoviridae , Brasil , China , Equador , Genoma Viral , Glicoproteínas , Fases de Leitura Aberta , Filogenia , Doenças das Plantas , Vírus de Plantas/genética , Rhabdoviridae/genética
7.
EMBO Rep ; 18(10): 1801-1816, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28808113

RESUMO

The regulation of inflammation is pivotal for preventing the development or reoccurrence of multiple sclerosis (MS). A biased ratio of high-M1 versus low-M2 polarized microglia is a major pathological feature of MS Here, using microarray screening, we identify the long noncoding RNA (lncRNA) GAS5 as an epigenetic regulator of microglial polarization. Gain- and loss-of-function studies reveal that GAS5 suppresses microglial M2 polarization. Interference with GAS5 in transplanted microglia attenuates the progression of experimental autoimmune encephalomyelitis (EAE) and promotes remyelination in a lysolecithin-induced demyelination model. In agreement, higher levels of GAS5 are found in amoeboid-shaped microglia in MS patients. Further, functional studies demonstrate that GAS5 suppresses transcription of TRF4, a key factor controlling M2 macrophage polarization, by recruiting the polycomb repressive complex 2 (PRC2), thereby inhibiting M2 polarization. Thus, GAS5 may be a promising target for the treatment of demyelinating diseases.


Assuntos
Microglia/fisiologia , Esclerose Múltipla/fisiopatologia , RNA Longo não Codificante/genética , Diferenciação Celular , Doenças Desmielinizantes/fisiopatologia , Encefalomielite Autoimune Experimental , Epigênese Genética , Regulação da Expressão Gênica , Humanos , Inflamação , Macrófagos , Esclerose Múltipla/genética , RNA Longo não Codificante/metabolismo
8.
Int J Mol Sci ; 20(15)2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31370145

RESUMO

Chitin synthase is a critical enzyme that catalyzes N-acetylglucosamine to form chitin, which plays an important role in the growth and development of insects. In this study, we identified a chitin synthase gene (CHS) with a complete open reading frame (ORF) of 3180 bp from the genome database of Diaphorina citri, encoding a protein of 1059 amino acid residues with the appropriate signature motifs (EDR and QRRRW). Reverse transcription-quantitative PCR (RT-qPCR) analysis suggested that D. citri CHS (DcCHS) was expressed throughout all developmental stages and all tissues. DcCHS had the highest expression level in the integument and fifth-instar nymph stage. Furthermore, the effects of diflubenzuron (DFB) on D. citri mortality and DcCHS expression level were investigated using fifth-instar nymph through leaf dip bioassay, and the results revealed that the nymph exposed to DFB had the highest mortality compared with control group (Triton-100). Silencing of DcCHS by RNA interference resulted in malformed phenotypes and increased mortality with decreased molting rate. In addition, transmission electron microscopy (TEM) and fluorescence in situ hybridization (FISH) also revealed corresponding ultrastructural defects. Our results suggest that DcCHS might play an important role in the development of D. citri and can be used as a potential target for psyllid control.


Assuntos
Quitina Sintase/genética , Genoma de Inseto , Hemípteros/genética , Proteínas de Insetos/genética , Ninfa/genética , Interferência de RNA , Sequência de Aminoácidos , Animais , Quitina Sintase/antagonistas & inibidores , Quitina Sintase/metabolismo , Citrus/parasitologia , Diflubenzuron/farmacologia , Frutas/parasitologia , Regulação da Expressão Gênica no Desenvolvimento , Hemípteros/efeitos dos fármacos , Hemípteros/enzimologia , Hemípteros/crescimento & desenvolvimento , Controle de Insetos , Proteínas de Insetos/antagonistas & inibidores , Proteínas de Insetos/metabolismo , Muda/efeitos dos fármacos , Muda/genética , Ninfa/efeitos dos fármacos , Ninfa/crescimento & desenvolvimento , Ninfa/metabolismo , Fases de Leitura Aberta , Filogenia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
9.
J Neurosci ; 36(35): 9253-66, 2016 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-27581464

RESUMO

UNLABELLED: T-helper 17 (Th17) cells play an important role in the pathogenesis of multiple sclerosis (MS), an autoimmune demyelinating disease that affects the CNS. In the present study, MicroRNA sequencing (miRNA-seq) was performed in mouse Th0 and Th17 cells to determine the critical miRNAs that are related to Th17 differentiation. We found that miR-30a was significantly downregulated during mouse Th17 differentiation. In addition, the level of miR-30a in CD4(+) T cells from peripheral blood of MS patients and experimental autoimmune encephalomyelitis (EAE) animal models was also decreased and inversely correlated with the expression of interleukin 17a, the canonical cytokine of Th17 cells. Moreover, overexpression of miR-30a inhibited Th17 differentiation and prevented the full development of EAE, whereas interference of miR-30a promoted Th17 differentiation. Mechanism studies showed that miR-30a reduced IRF4 expression by specifically binding with the 3'-untranslated region. Through screening of 640 different Food and Drug Administration (FDA)-approved drugs, we found that disulfiram and diphenhydramine hydrochloride were effective candidates for inhibiting Th17 differentiation and ameliorating EAE development through upregulating miR-30a. To our knowledge, the present work is not only the first miRNA-seq study focusing on Th17 differentiation, but also the first chemical screening for FDA-approved drugs that inhibit Th17 differentiation through regulating miRNA expression. SIGNIFICANCE STATEMENT: The present work is the first miRNA sequencing (miRNA-seq) study focusing on T-helper 17 (Th17) differentiation. By miRNA deep sequencing, we found that miR-30a was downregulated during Th17 differentiation. miR-30a was also decreased in CD4(+) T cells from multiple sclerosis patients and experimental autoimmune encephalomyelitis (EAE) mice. miR-30a reduced IRF4 expression by specific binding with the 3'-untranslated region and thus suppressed Th17 differentiation and prevented the full development of EAE. Interestingly, by performing a chemical screen with Food and Drug Administration-approved small-molecule drugs, we found that disulfiram and diphenhydramine upregulated miR-30a and suppressed Th17-associated autoimmune demyelination.


Assuntos
Difenidramina/farmacologia , Dissulfiram/farmacologia , Encefalomielite Autoimune Experimental/metabolismo , Interleucina-17/metabolismo , MicroRNAs/metabolismo , Regulação para Cima/efeitos dos fármacos , Animais , Estudos de Casos e Controles , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/prevenção & controle , Feminino , Células HEK293 , Humanos , Fatores Reguladores de Interferon/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína Proteolipídica de Mielina/toxicidade , Glicoproteína Mielina-Oligodendrócito/toxicidade , Fragmentos de Peptídeos/toxicidade , Estatísticas não Paramétricas , Transfecção
10.
J Neurosci ; 35(16): 6350-65, 2015 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-25904788

RESUMO

The major challenge for progressive multiple sclerosis therapy is the promotion of remyelination from inflammation-induced demyelination. A switch from an M1- to an M2-dominant polarization of microglia is critical in these repair processes. In this study, we identified the homeobox gene msh-like homeobox-3 (Msx3) as a new pivotal regulator for microglial polarization. MSX3 was induced during microglia M2 polarization and repressed in M1 cells. The expression of MSX3 in microglia was dynamically regulated during experimental autoimmune encephalomyelitis (EAE), which is an animal model of multiple sclerosis. The overexpression of MSX3 in microglia promoted M2 but impeded M1 polarization. Interrupting MSX3 expression in microglia accelerated inflammation-induced demyelination and neurodegeneration. The conditioned medium from MSX3-transduced microglia promoted oligodendrocyte progenitor survival, differentiation, and neurite outgrowth. The adoptive transfer of MSX3-transduced microglia suppressed EAE and facilitated remyelination within the murine CNS in EAE and the LPC model. Mechanically, chromatin immunoprecipitation assays also indicated that MSX3 directly regulated three key genes associated with microglia M2 polarization, including Pparg, Stat6, and Jak3. Importantly, we found that overexpression of MSX3 in human-derived microglia represents the M2 phenotype and ameliorated EAE after intraventricular injection. Our findings suggest a new homeobox protein-dependent mechanism for driving microglia M2 polarization and identify MSX3 as an attractive therapeutic approach for preventing inflammation-induced demyelination and promoting remyelination.


Assuntos
Polaridade Celular , Doenças Desmielinizantes/metabolismo , Encefalomielite Autoimune Experimental/metabolismo , Proteínas de Homeodomínio/metabolismo , Microglia/citologia , Microglia/metabolismo , Bainha de Mielina/fisiologia , Animais , Apoptose/fisiologia , Células Cultivadas , Doenças Desmielinizantes/patologia , Encefalomielite Autoimune Experimental/patologia , Feminino , Regulação da Expressão Gênica/fisiologia , Proteínas de Homeodomínio/biossíntese , Humanos , Janus Quinase 3/metabolismo , Camundongos , Degeneração Neural/metabolismo , Degeneração Neural/prevenção & controle , Neuritos/fisiologia , PPAR gama/metabolismo , Fator de Transcrição STAT6/metabolismo , Células-Tronco/patologia , Células-Tronco/fisiologia
11.
Glia ; 63(4): 684-98, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25530119

RESUMO

Differentiation of oligodendrocyte precursor cells (OPCs) is a prerequisite for both developmental myelination and adult remyelination in the central nervous system. The molecular mechanisms underlying OPC differentiation remain largely unknown. Here, we show that the thirty-kDa HIV-1 Tat interacting protein (TIP30) is a negative regulator in oligodendrocyte development. The TIP30(-/-) mice displayed an increased myelin protein level at postnatal day 14 and 21. By using a primary OPC culture system, we demonstrated that overexpression of TIP30 dramatically inhibited the stage progression of differentiating OPCs, while knockdown of TIP30 enhanced the differentiation of oligodendroglial cells remarkably. Moreover, overexpression of TIP30 was found to sequester the transcription factor Olig1 in the cytoplasm and weaken its nuclear translocation due to the interaction between TIP30 and Olig1, whereas knockdown of TIP30 led to more Olig1 localized in the nucleus in the initiation stage during OPC differentiation. In the cuprizone-induced demyelination model, there was a dramatic increase in NG2-expressing cells with nuclear location of Olig1 in the corpus callosum during remyelination. In contrast, within chronic demyelinated lesions in multiple sclerosis, TIP30 was abnormally expressed in NG2-expressing cells, and few nuclear Olig1 was observed in these cells. Taken together, our findings suggest that TIP30 plays a negative regulatory role in oligodendroglial differentiation.


Assuntos
Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Citoplasma/metabolismo , Oligodendroglia/citologia , Proteínas Repressoras/metabolismo , Células-Tronco/citologia , Proteínas Supressoras de Tumor/metabolismo , Animais , Animais Recém-Nascidos , Antígenos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Biomarcadores/metabolismo , Técnicas de Cultura de Células , Núcleo Celular/metabolismo , Corpo Caloso/citologia , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Knockout , Bainha de Mielina/metabolismo , Fibras Nervosas Mielinizadas/metabolismo , Oligodendroglia/metabolismo , Oligodendroglia/fisiologia , Proteoglicanas/metabolismo , Proteínas Repressoras/deficiência , Proteínas Repressoras/genética , Proteínas Supressoras de Tumor/deficiência , Proteínas Supressoras de Tumor/genética
12.
Brain Behav Immun ; 48: 287-300, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25900440

RESUMO

Glial cell response to injury has been well documented in the pathogenesis after traumatic brain injury (TBI) and spinal cord injury (SCI). Although microglia, the resident macrophages in the central nervous system (CNS), are responsible for clearing debris and toxic substances, excessive activation of these cells will lead to exacerbated secondary damage by releasing a variety of inflammatory and cytotoxic mediators and ultimately influence the subsequent repair after CNS injury. In fact, inhibition of microgliosis represents a therapeutic strategy for CNS trauma. We here showed that nitidine, a benzophenanthridine alkaloid, restricted reactive microgliosis and promoted CNS repair after traumatic injury. Nitidine was shown to prevent cultured microglia from LPS-induced reactive activation by regulation of ERK and NF-κB signaling pathway. Furthermore, the nitidine-mediated inhibition of microgliosis was also shown in injured brain and spinal cord, which significantly increased neuronal survival and decreased neural tissue damage after injury. Importantly, behavioral analysis revealed that nitidine-treated mice with SCI had improved functional recovery as assessed by Basso Mouse Scale and swimming test. Together, these findings indicated that nitidine increased CNS tissue sparing and improved functional recovery by attenuating reactive microgliosis, suggestive of the potential therapeutic benefit for CNS injury.


Assuntos
Benzofenantridinas/farmacologia , Lesões Encefálicas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Ativação de Macrófagos/efeitos dos fármacos , Microglia/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Transdução de Sinais/efeitos dos fármacos , Traumatismos da Medula Espinal/metabolismo , Animais , Lesões Encefálicas/patologia , Lipopolissacarídeos/farmacologia , Camundongos , Microglia/metabolismo , Microglia/patologia , NF-kappa B/metabolismo , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Transdução de Sinais/fisiologia , Traumatismos da Medula Espinal/patologia
13.
J Biol Chem ; 288(47): 34276-34286, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24129566

RESUMO

TROY can functionally substitute p75 to comprise the Nogo receptor complex, which transduces the inhibitory signal of myelin-associated inhibitory factors on axon regeneration following CNS injury. The inhibition of neurite extension relies on TROY-dependent RhoA activation, but how TROY activates RhoA remains unclear. Here, we firstly identified Rho guanine nucleotide dissociation inhibitor α (RhoGDIα) as a binding partner of TROY using GST pull-down combined with two-dimensional gel electrophoresis and mass spectra analysis. The interaction was further confirmed by coimmunoprecipitation in vitro and in vivo. Deletion mutagenesis revealed that two regions of the TROY intracellular domain (amino acids 234-256 and 321-350) were essential for the interaction with RhoGDIα. Secondly, TROY and RhoGDIα were coexpressed in postnatal dorsal root ganglion neurons, cortex neurons, and cerebellar granule neurons (CGNs). Thirdly, TROY/RhoGDIα association was potentiated by Nogo-66 and was independent of p75/RhoGDIα interaction. Fourthly, TROY/RhoGDIα interaction was still able to activate RhoA when p75 was deficient. Furthermore, RhoA activation was decreased dramatically when TROY was knocked down in p75-deficient CGNs cells. Finally, RhoGDIα overexpression abolished RhoA activation and following neurite outgrowth inhibition by Nogo-66 in both wild-type and p75-deficient CGNs. These results showed that the association of RhoGDIα with TROY contributed to TROY-dependent RhoA activation and neurite outgrowth inhibition after Nogo-66 stimulation.


Assuntos
Proteínas da Mielina/metabolismo , Neuritos/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Inibidor alfa de Dissociação do Nucleotídeo Guanina rho/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Humanos , Camundongos , Proteínas da Mielina/genética , Proteínas Nogo , Estrutura Terciária de Proteína , Ratos , Ratos Sprague-Dawley , Receptores do Fator de Necrose Tumoral/genética , Deleção de Sequência , Proteínas rho de Ligação ao GTP/genética , Proteínas rho de Ligação ao GTP/metabolismo , Inibidor alfa de Dissociação do Nucleotídeo Guanina rho/genética , Proteína rhoA de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/metabolismo
14.
Hepatol Res ; 44(14): E464-70, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24720373

RESUMO

AIM: To investigate the association between red cell distribution width (RDW) and the severity of hepatitis B virus (HBV)-related liver diseases. METHODS: Sixty-nine patients with chronic hepatitis B (CHB) and 61 patients with HBV-related liver cirrhosis were enrolled in the present study. Forty-one healthy individuals were included as controls. Hematological parameters, hepatitis B e-antigen (HBeAg) status, HBV DNA levels and liver biochemistry were analyzed. Child-Pugh scores and Model for End-Stage Liver Disease (MELD) scores of the patients with HBV-related liver cirrhosis were calculated. RESULTS: The RDW was significantly higher in patients with HBV-related liver cirrhosis as compared with CHB patients and healthy controls. RDW was slightly higher in CHB patients as compared with healthy controls. An increasing correlation of RDW with Child-Pugh grades was found. RDW was positively correlated with Child-Pugh scores and MELD scores. In patients with HBV-related liver cirrhosis, RDW was also positively correlated with total bilirubin and negatively correlated with hemoglobin and serum albumin concentration. However, no significant difference was found between HBeAg positive and negative patients and no significant correlation between RDW and HBV DNA levels was found. CONCLUSION: The RDW was elevated in CHB patients and patients with HBV-related liver cirrhosis and was positively correlated with the severity of HBV-related liver cirrhosis. RDW is a potential index to assess the severity of HBV-related liver diseases.

15.
J Child Lang ; 41(4): 861-89, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23883442

RESUMO

The present study investigated Mandarin-speaking children's acquisition of the polarity sensitive item renhe 'any' in Mandarin Chinese. Like its English counterpart any, renhe can be used as a negative polarity item (NPI), or as a free choice (FC) item, and both the distribution and interpretation of renhe are governed by the same syntactic and semantic constraints as English any. Using a Truth Value Judgment Task, the present study tested five-year-old Mandarin-speaking children's comprehension of FC renhe in sentences containing the modal word neng 'can', and tested children's comprehension of NPI renhe in sentences containing the temporal conjunction zai…zhiqian 'before'. Most children demonstrated knowledge of the interpretation of both FC renhe and NPI renhe despite a paucity of relevant adult input. Like adults, however, Mandarin-speaking children do not use renhe frequently in ordinary conversation, due to the availability of alternative colloquial expressions (wh-pronouns) that also convey children's intended meanings.


Assuntos
Compreensão , Desenvolvimento da Linguagem , Idioma , Linguística , Semântica , Criança , Pré-Escolar , China , Feminino , Humanos , Masculino , Percepção da Fala , Comportamento Verbal , Vocabulário
16.
Biosens Bioelectron ; 246: 115872, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38039731

RESUMO

Multicolor-based visual immunosensor is a promising tool for rapid analysis without the use of bulky instruments. Herein, an anti-fenitrothion nanobody-alkaline phosphatase fusion protein (VHHjd8-ALP) was employed to develop a multicolor visual immunosensor (MVIS) and a ratiometric fluorescence MVIS (RFMVIS, respectively). After one-step competitive immunoassay, the VHHjd8-ALP bound to microplate catalyzed phenyl phosphate disodium salt (ArP) into phenol. Under high alkaline condition (pH 12), the phenol reduced KMnO4 to intermediate (K2MnO4) and further to MnO2 in alkaline condition (pH 12), accompanied by a visible color transition of purple-green-yellow, which can be used for semiquantitative visual analysis or qualitative detection by measuring RGB value. RFMVIS was proposed on the basis of MVIS to further improve sensitivity. The CdTe quantum dot and fluorescein were used as signal probes to develop the fluorescent immunosensor. The CdTe dots with red emission (644 nm) was quenched by oxidation of KMnO4, whereas the fluorescein with green emission (520 nm) remained constant, accompanied by a fluorescent color transition of green-yellow-red. By measuring the ratio of the fluorescence intensity (I644/I520), the ratiometric fluorescence immunosensor was developed for qualitative analysis. The two visual immunosensors were sensitive and simple, and they showed good accuracy and practicability in the recovery test, thus are ideal tools for rapid screening.


Assuntos
Técnicas Biossensoriais , Compostos de Cádmio , Pontos Quânticos , Permanganato de Potássio , Fenitrotion , Fosfatos , Compostos de Manganês , Telúrio , Imunoensaio , Óxidos , Fluoresceínas , Fenóis , Corantes Fluorescentes , Limite de Detecção , Espectrometria de Fluorescência
17.
Biomater Adv ; 166: 214006, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39265449

RESUMO

Ti-6Al-4V (wt%) is the most widely used titanium alloy and its additive manufactured (or 3D printed) parts with near net-shape have provided great advantages for biomedical applications. While the impact of surface roughness on the biocompatibility of 3D-printed Ti-6Al-4V part is recognized, further exploration is needed to fully understand this complex relationship. Hence, this study presents a comprehensive evaluation of as-printed Ti-6Al-4V structures, both with and without surface texturing, with particular focus on the fibroblast response. Alongside a flat surface, or as-printed surface, two different types of surface textures: diamond texture and diamond crystal texture, were meticulously designed and printed through laser powder bed fusion (LPBF). The viability, cell adhesion, and morphology of human and murine fibroblasts seeded on the surface patterns was investigated, as well as the distribution of extracellular matrix (ECM) proteins (collagen I, fibronectin). The results demonstrated that the as-fabricated surface morphologies did not impact fibroblast viability, however, a reduced density of human fibroblasts was observed on the diamond texture surface, likely owing to the upright strut structure preventing cell adhesion. Interestingly, spreading of the human, but not murine, fibroblasts was limited by the remaining partially-sintered powders. The relative intensity of ECM protein signals was unaffected, however, ECM protein distribution across the surfaces was also altered. Thus, the as-printed substrates, particularly with diamond crystal struts, present a promising avenue for the cost-effective and efficient fabrication of Ti-6Al-4V components for medical applications in the future.

18.
Environ Toxicol ; 28(2): 98-106, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21544917

RESUMO

Diarrhetic shellfish poisoning (DSP) is a gastrointestinal illness with symptoms such as diarrhea, nausea, vomiting, headache, chills and moderate to severe abdominal pain. DSP has been recognized as a worldwide public health problem, causing great concern to the shellfish industry. Accumulation of DSP in shellfish is an unpredictable phenomenon that necessitates the implementation of a widespread collection and thorough monitoring program for mollusk toxicity. Therefore, development of accurate analytical protocols for the rapid determination of toxicity levels would be necessary. In this study we investigated cytoskeletal changes induced by okadaic acid in HL-7702 Liver Cells and developed a new cytotoxicity assay for detection and quantitation of DSP. This assay is based on fluorometric of F-actin depolymerization induced by okadaic acid (OA) compounds in HL-7702 liver cell line. The measurable range of OA was 2.5 ∼ 40 nmol/L. The detection limit of the F-actin assay for OA was 2.01 µg/100 g muscles in shellfish extracts. The performance of this assay has been evaluated by comparative analysis of shellfish samples by the fluorescent assay, mouse bioassay, and ELISA assay. Comparison of the results by all three methods revealed excellent consistency, the results of fluorescent assay were in significant correlation with ELISA assay (R(2) = 0.830). Examination of F-actin assay is very convenient, rapid, and sensitive, which can be used to quantify the amount of OA in shellfish samples.


Assuntos
Actinas/química , Fluorometria/métodos , Hepatócitos/efeitos dos fármacos , Ácido Okadáico/toxicidade , Intoxicação por Frutos do Mar/diagnóstico , Animais , Apoptose/efeitos dos fármacos , Bioensaio/métodos , Bivalves/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Limite de Detecção , Camundongos , Frutos do Mar/toxicidade
19.
Materials (Basel) ; 16(24)2023 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-38138728

RESUMO

Platform heating is one of the effective strategies used in laser powder bed fusion (LPBF) to avoid cracking during manufacturing, especially when building relatively large-size components, as it removes significant process-induced residual strains. In this work, we propose a novel and simple method to spare the elaborate post-processing heat treatment typically needed for LPBF Al-Sc alloys without compromising the mechanical properties. We systematically investigated the effects of LPBF platform heating at 200 °C on the residual stress relief, microstructure, and mechanical performance of a high-strength Al-Mn-Sc alloy. The results reveal that LPBF platform heating at 200 °C is sufficient to largely relieve the process-induced residual stresses compared to parts built on an unheated 35 °C platform. Meanwhile, the platform heating triggered the dynamic precipitation of uniformly dispersed (1.5-2 nm) Sc-rich nano-clusters. Their formation in a high number density (1.75 × 1024 m-3) resulted in a ~20% improvement in tensile yield strength (522 MPa) compared to the build on the unheated platform, without sacrificing the ductility (up to 18%). The improved mechanical properties imply that platform heating at 200 °C can strengthen the LPBF-synthesised Sc-containing Al alloys via in situ aging, which is further justified by an in situ measurement study revealing that the developing temperatures in the LPBF part are within the aging temperature range of Al-Sc alloys. Without any post-LPBF treatments, these mechanical properties have proven better than those of most Al-Sc alloys through long-time post-LPBF heat treatment.

20.
Front Microbiol ; 14: 1119619, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143541

RESUMO

Huanglongbing (HLB) is a global devastating citrus disease that is mainly caused by "Candidatus Liberibacter asiaticus" (CLas). It is mostly transmitted by the insect Asian citrus psyllid (ACP, Diaphorina citri) in a persistent and proliferative manner. CLas traverses multiple barriers to complete an infection cycle and is likely involved in multiple interactions with D. citri. However, the protein-protein interactions between CLas and D. citri are largely unknown. Here, we report on a vitellogenin-like protein (Vg_VWD) in D. citri that interacts with a CLas flagellum (flaA) protein. We found that Vg_VWD was upregulated in CLas-infected D. citri. Silencing of Vg_VWD in D. citri via RNAi silencing significantly increased the CLas titer, suggesting that Vg_VWD plays an important role in the CLas-D. citri interaction. Agrobacterium-mediated transient expression assays indicated that Vg_VWD inhibits BAX- and INF1-triggered necrosis and suppresses the callose deposition induced by flaA in Nicotiana benthamiana. These findings provide new insights into the molecular interaction between CLas and D. citri.

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