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1.
Scand J Gastroenterol ; 59(4): 445-455, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38053282

RESUMO

BACKGROUND: Accompanied by the growing prevalence of nonalcoholic fatty liver disease (NAFLD), the coexistence of chronic hepatitis B (CHB) and NAFLD has increased. In the context of CHB, there is limited understanding of the factors that influence the development of NASH. METHODS: We enrolled CHB combined NAFLD patients who had liver biopsy and divided them to NASH vs. non-NASH groups. A whole transcriptome chip was used to examine the expression profiles of long noncoding RNAs (lncRNAs) and mRNA in biopsied liver tissues. The function analysis of HIGD1A were performed. We knocked down or overexpressed HIGD1A in HepG2.2.15 cells by transient transfection of siRNA-HIGD1A or pcDNA-HIGD1A. In vivo investigations were conducted using hepatitis B virus (HBV) transgenic mice. RESULTS: In 65 patients with CHB and NAFLD, 28 were patients with NASH, and 37 were those without NASH. After screening 582 differentially expressed mRNAs, GO analysis revealed differentially expressed mRNAs acting on nicotinamide adenine dinucleotide phosphate (NADPH), which influenced redox enzyme activity. KEGG analysis also shown that they were involved in the NAFLD signaling pathway. The function analysis revealed that HIGD1A was associated with the mitochondrion. Then, both in vivo and in vitro CHB model, HIGD1A was significantly higher in the NASH group than in the non-NASH group. HIGD1A knockdown impaired mitochondrial transmembrane potential and induced cell apoptosis in HepG2.2.15 cells added oleic acid and palmitate. On the contrary, hepatic HIGD1A overexpression ameliorated free fatty acids-induced apoptosis and oxidative stress. Furthermore, HIGD1A reduced reactive oxygen species (ROS) level by increasing glutathione (GSH) expression, but Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)/Acetyl-CoA carboxylase (ACC) pathway was not involved. CONCLUSION: Both in vivo and in vitro CHB model, an upward trend of HIGD1A was observed in the NASH-related inflammatory response. HIGDIA played a protective role in cells against oxidative stress. Our data suggested that HIGD1A may be a positive regulator of NASH within the CHB context.


Assuntos
Hepatite B Crônica , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Humanos , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatite B Crônica/complicações , Fígado/patologia , Vírus da Hepatite B/genética , Espécies Reativas de Oxigênio/metabolismo
2.
Materials (Basel) ; 16(13)2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37444927

RESUMO

Copper is the most common interconnecting material in the field of microelectronic packaging, which is widely used in advanced electronic packaging technologies. However, with the trend of the miniaturization of electronic devices, the dimensions of interconnectors have decreased from hundreds of microns to tens of or even several microns, which has brought serious reliability issues. As a result, nanotwinned copper (nt-Cu) has been proposed as a potential candidate material and is being certified progressively. Firstly, the physical properties of nt-Cu have been widely studied. Notably, the higher thermal stability and oxidation resistance of the (111) texture causes nt-Cu to maintain excellent physical properties under high-temperature serving conditions. Secondly, recent works on the electrolyte and electroplating processes of nt-Cu on wafer substrates are summarized, focusing on how to reduce the thickness of the transition layer, improve the twin density, and achieve complicated pattern filling. Thirdly, nt-Cu can effectively eliminate Kirkendall voids when it serves as UBM or a CuP. Additionally, the high (111) texture can control the preferred orientation of interfacial intermetallic compounds (IMCs) at the Cu-Sn interface, which should be helpful to improve the reliability of solder joints. nt-Cu has superior electromigration resistance and antithermal cycling ability compared to ordinary copper RDLs and TSVs. Above all, nt-Cu has attracted much attention in the field of microelectronic packaging in recent years. The preparation-performance-reliability interrelationship of nt-Cu is summarized and displayed in this paper, which provides a solid theoretical basis for its practical applications.

3.
Plant Mol Biol ; 112(6): 309-323, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37378835

RESUMO

Aerial root mucilage can enhance nitrogen fixation by providing sugar and low oxygen environment to the rhizosphere microbiome in Sierra Mixe maize. Aerial root mucilage has long been documented in sorghum (Sorghum bicolor), but little is known about the biological significance, genotypic variation, and genetic regulation of this biological process. In the present study, we found that a large variation of mucilage secretion capacity existed in a sorghum panel consisting of 146 accessions. Mucilage secretion occurred primarily in young aerial roots under adequately humid conditions but decreased or stopped in mature long aerial roots or under dry conditions. The main components of the mucilage-soluble were glucose and fructose, as revealed by sugar profiling of cultivated and wild sorghum. The mucilage secretion capacity of landrace grain sorghum was significantly higher than that of wild sorghum. Transcriptome analysis revealed that 1844 genes were upregulated and 2617 genes were downregulated in mucilage secreting roots. Amongst these 4461 differentially expressed genes, 82 genes belonged to glycosyltransferases and glucuronidation pathways. Sobic.010G120200, encoding a UDP-glycosyltransferase, was identified by both GWAS and transcriptome analysis as a candidate gene, which may be involved in the regulation of mucilage secretion in sorghum through a negative regulatory mechanism.


Assuntos
Sorghum , Sorghum/genética , Sorghum/metabolismo , Transcriptoma , Açúcares/metabolismo , Estudo de Associação Genômica Ampla , Polissacarídeos/metabolismo , Perfilação da Expressão Gênica , Grão Comestível/genética , Variação Genética
4.
Obes Facts ; 16(5): 427-434, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37231905

RESUMO

INTRODUCTION: The prevalence of non-alcoholic fatty liver disease (NAFLD) in non-lean patients is significantly increased, and obesity significantly increases the risk of cirrhosis and HCC in NAFLD patients. However, whether there is a difference in clinical manifestations of NAFLD between overweight and obesity remains unclear. The objective of this study was to assess the clinical and histological features of NAFLD among a non-lean population. METHODS: Current study enrolled consecutive non-lean (body mass index [BMI] >23 kg/m2) patients with NAFLD and available liver biopsy results. Patients were stratified by BMI into two groups for the comparison of their clinical and histological variables, which included the overweight (BMI 23∼<28 kg/m2) and the obese (BMI ≥28 kg/m2). Risk factors for moderate to severe fibrosis (stage >1) were also analyzed through the logistic regression model. RESULTS: Among 184 non-lean patients with metabolic-associated fatty liver disease enrolled, 65 and 119 were overweight and obese, respectively. Patients in the obesity group had a significantly lower level of gamma-glutamyl transpeptidase, higher levels of platelet, glucose, prothrombin time, and more common of moderate to severe inflammatory activity when compared to those in the overweight group. However, a significant low frequency of moderate to severe fibrosis was found in the obesity group versus the overweight group (19.33% vs. 40.00%, p = 0.002). Binary logistics regression analysis of fibrosis found that aspartate transaminase (AST), BMI, alanine transaminase (ALT), and cholesterol (CHOL) were independent predictors for moderate to severe fibrosis in non-lean patients with NAFLD. Compared with the traditional fibrosis-4 (AUC = 0.77) and aminotransferase to platelet ratio index (AUC = 0.79) indexes, the combined index based on AST, BMI, ALT, and CHOL was more accurate in predicting moderate to severe fibrosis in non-lean patients with NAFLD (AUC = 0.87). CONCLUSIONS: Clinical and histological features differed between obesity and overweight patients with NAFLD. When compared to the traditional serum markers, the combination index including AST, BMI, ALT, and CHOL provided a better model to predict moderate to severe fibrosis in non-lean patients with NAFLD.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/complicações , Sobrepeso/complicações , Carcinoma Hepatocelular/complicações , Neoplasias Hepáticas/complicações , Obesidade/complicações , Cirrose Hepática/complicações , Fibrose , Índice de Massa Corporal
5.
Nanotechnology ; 34(1)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36191523

RESUMO

Nanotwinned copper is a potential microelectronic interconnection material due to its superior strength and conductivity, however, its filling ability is urgently needed to improve before its application in the field of advanced packaging. The effect of additive (sodium thiazolinyl dithiopropane sulphonate, SH110) addition on the surface roughness, microstructure, mechanical properties and filling capacity of nanotwinned copper films was investigated. The surface roughness and grain size were firstly reduced then increased with the increasing concentrations of SH110, reaching the minimum value at 10 ppm. It was noticed that copper films with 10 ppm SH110 also possessed superior tensile strength and elongation, which were measured as 481 MPa and 3.68% on average of 12µm thick samples by dynamic thermo-mechanical analyzer. Further, their uniformity and flatness of redistributed layers (RDLs) were controlled as 2% and 1.9%, which were significantly improved compared to the samples without SH110 (7.6% and 4.7%). As demonstrated by linear sweep voltammetry analysis and galvanostatic measurement, the SH110 could cooperate well with gelatin and serve as a combination of accelerator and leveler, resulting in the improvement of filling capacity for nanotwinned copper RDLs.

6.
Virus Res ; 298: 198405, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33775752

RESUMO

BACKGROUND/AIMS: To identify the inflammatory damage caused by chronic hepatitis B (CHB) in patients of chronic hepatitis B virus (HBV) infection complicated with non-alcoholic fatty liver disease (NAFLD), then guiding clinicians to carry out antiviral treatment. METHODS: According to the pathological features of liver biopsy, treatment-naïve obese patients of chronic HBV infection complicated with NAFLD who had elevated alanine transaminase (ALT) were divided into CHB group and NASH group. Transcriptome chips were used to analyze the expression profiles of long non-coding RNA (lncRNA) and mRNA in liver puncture tissues from the two groups. The chip data of CHB and NASH groups were analyzed for differential expression analysis, gene function analysis, signal pathway analysis, target gene prediction and competing endogenous RNAs (ceRNA) network analysis. RESULTS: By comparing CHB group with NASH group, a total of 44 differentially expressed lncRNAs and 567 differentially expressed mRNAs were screened. GO analysis predicted that the differentially expressed mRNAs may affect monooxygenase activity and oxidoreductase activity. KEGG analysis predicted that the differentially expressed mRNAs may be related to signaling pathways involved in oxidative phosphorylation, phagosomes, and NAFLD. Differential analysis of lncRNA shown that the expression of metastasis associated in lung adenocarcinoma transcript 1 (MALAT1) in CHB group was significantly upregulated. Subsequently, through target gene prediction and ceRNA network analysis, we found thioredoxin interacting protein (TXNIP), which was significantly upregulated in the CHB group and had a ceRNA relationship with MALAT1. It is predicted that there may be a ceRNA regulation relationship of MALAT1/hsa-miR- 20b-5p/TXNIP. CONCLUSION: The MALAT1/hsa-miR-20b-5p/TXNIP axis may mediate CHB-induced inflammatory damage in chronic HBV infection complicated with NAFLD, and the mechanism may be related to the activation of NLRP3 inflammatory bodies and downstream inflammatory responses.


Assuntos
Proteínas de Transporte , Hepatite B Crônica , MicroRNAs , Hepatopatia Gordurosa não Alcoólica , RNA Longo não Codificante , Proteínas de Transporte/genética , Hepatite B Crônica/complicações , Hepatite B Crônica/genética , Humanos , Inflamação , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , RNA Longo não Codificante/genética , RNA Mensageiro/genética
7.
J Viral Hepat ; 27(10): 1044-1051, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32384194

RESUMO

Little data exist on basal core promoter/precore (BCP/PC) mutations in chronic hepatitis B (CHB) patients at the immune-tolerance (IT) phase. We studied consecutive treatment-naïve, CHBe-antigen (HBeAg)-positive patients who had undergone liver biopsy and genotyping. Those in the IT phase or immune-clearance (IC) phase were enrolled for comparison of the frequency of BCP/PC mutations and their clinical presentations. Subgroup analyses for the IT group were also performed between patients with and without mutations, and IC patients between fibrosis stages ≤2 vs fibrosis >2. Among 301 patients enrolled, 88/301 (29.24%) and 213/301 (70.76%) were at the IT and IC phase, respectively. The frequency of BCP/PC mutations in IT phase was significantly lower than those in IC phase (15.91% vs 64.79%, P < .001). The BCP mutation only was significantly more frequent than the PC mutation in both groups and also in all IC subgroups. IT patients with BCP/PC mutations had significantly higher quantitative anti-HBc levels compared with those of patients with wild-type virus (P < .05). They also had significantly lower mean levels of alanine transaminase, aspartate transaminase, total bilirubin and qAnti-HBc compared with those of IC patients (all P < .05). Additionally, they were significantly younger in mean age, had higher platelet count, higher levels of HBV DNA and surface antigen, as well as higher frequency of genotype B than those of IC patients with fibrosis >2 (all P < .05). BCP/PC mutations were found in IT patients with CHB. They had distinct clinical characteristics when compared with patients with wild-type or at IC phase. Further studies are needed to understand their natural history and treatment outcomes.


Assuntos
Hepatite B Crônica , Hepatite B , DNA Viral , Genótipo , Antígenos do Núcleo do Vírus da Hepatite B/genética , Antígenos E da Hepatite B , Vírus da Hepatite B/genética , Humanos , Mutação
8.
J Microsc ; 279(3): 212-216, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31985812

RESUMO

A site-specific xenon plasma focused ion beam preparation technique for microcantilever samples (1-20 µm width and 1:10 aspect ratio) is presented. The novelty of the methodology is the use of a chunk lift-out onto a clean silicon wafer to facilitate easy access of a low-cost probe type indenter which provides bending force measurement. The lift-out method allows sufficient room for the indenter and a line of sight for the electron beam to enable displacement measurement. An electroplated nanotwinned copper (NTC) was cut to a 3 × 3 × 25 µm microbeam and in situ mechanically tested using the developed technique. It demonstrated measured values of Youngs modulus of 78.7 ± 11 GPa and flow stress of 0.80 ± 0.05 GPa, which is within the ranges reported in the literature. LAY DESCRIPTION: In this paper a site specific method is present for making particularly small mechanical tests samples, of the order of 100th the size of a human hair. These small samples can then be used to determine the mechanical properties of the bulk material. Copper with a nano twinned grain structure is used as a test medium. Ion milling was used to cut the sample to shape and a micro probe was used for mechanical testing. Ion milling can cut away very small volumes of material as it accelerates ions at the surface of the sample, atomically machining the sample. Micro probes are a cost-effective small-scale load measurement devices, however, they require a large area for accessing the sample. The indenter requirements are a problem when making you samples with ion milling as ion millers are best at making small cuts. Our aim was to design a cutting strategy which reduces the amount of cutting required while allowing samples to be fabricated anywhere on the sample. We used a chunk lift out technique to remove a piece of material which is then welded to a wafer of silicon this gives sufficient space around the sample for ion milling and testing. The additional space allowed easy access for the probe. A 3 × 3 × 10 µm micro cantilever beam was cut out from copper, this beam was then bent. The force from bending and distance bent was measured and converted into Youngs modulus which is a measure of flexibility. The modulus value measured was comparable to the values reported in other papers.

9.
Clinics (Sao Paulo) ; 74: e1077, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31596338

RESUMO

OBJECTIVES: This study investigated whether tissue Doppler imaging parameters, especially the peak systolic velocity of the left ventricular lead-implanted segment (Ss), affect cardiac resynchronization therapy response. METHODS: In this case-control study, 110 enrolled patients were divided into cases (responder group, n=65) and controls (nonresponder group, n=45) based on whether their left ventricular end-systolic volume was reduced by ≥15% at 6 months after surgery. Preoperative clinical and echocardiographic data were collected. Multivariate logistic regression models were used to analyze the factors affecting the response to cardiac resynchronization therapy, and receiver operating characteristic curves were plotted to evaluate their diagnostic values. RESULTS: The proportion of patients with left bundle branch block in the case group was higher than that in the control group. The control group showed a higher left atrial volume index, E/A ratio and E/Em ratio but lower Ss than that of the case group. A multivariate regression analysis showed that left bundle branch block, Ss, and an E/Em ratio>14 were independent risk factors affecting the response to cardiac resynchronization therapy. Ss=4.1 cm/s was the best diagnostic threshold according to the receiver operating characteristic curve. CONCLUSIONS: Ss is an important factor affecting the response to cardiac resynchronization therapy. Patients with heart failure associated with Ss<4.1 cm/s have a higher risk of nonresponse.


Assuntos
Terapia de Ressincronização Cardíaca , Ecocardiografia Doppler/métodos , Insuficiência Cardíaca/terapia , Ventrículos do Coração/diagnóstico por imagem , Idoso , Estudos de Casos e Controles , Feminino , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Volume Sistólico/fisiologia , Resultado do Tratamento
10.
Sci Technol Adv Mater ; 20(1): 876-901, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31528239

RESUMO

Electronic products are evolving towards miniaturization, high integration, and multi-function, which undoubtedly puts forward higher requirements for the reliability of solder joints in electronic packaging. Approximately 70% of failure in electronic devices originates during the packaging process, mostly due to the failure of solder joints. With the improvement of environmental protection awareness, lead-free solder joints have become a hot issue in recent years. This paper reviews the research progress on the reliability of lead-free solder joints and discusses the influence of temperature, vibration, tin whisker and electromigration on the reliability of solder joints. In addition, the measures to improve the reliability of solder joints are analyzed according to the problems of solder joints themselves, which provides a further theoretical basis for the study of the reliability of solder joints of electronic products in service.

11.
Sci Technol Adv Mater ; 20(1): 421-444, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31489052

RESUMO

With the development of lead-free solders in electronic packaging, Sn-Cu lead-free solder has attracted wide attention due to its excellent comprehensive performance and low cost. In this article, we present recent developments in Sn-Cu lead-free solder alloys. From the microstructure and interfacial structure, the evolution law of the internal structure of solder alloy/solder joint was analysed, and the model and theory describing the formation/growth mechanism of interfacial IMC were introduced. In addition, the effects of alloying, particle strengthening and process methods on the properties of Sn-Cu lead-free solders, including wettability, melting and mechanical properties, were described. Finally, we outline the issues that need to be resolved in the future research.

12.
ACS Appl Mater Interfaces ; 11(19): 17915-17924, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31026136

RESUMO

Here, a facile, low-cost, and high-efficiency method to construct a vertically aligned hexagonal boron nitride nanosheet (hBNN) thermal conduction channel structure is proposed to improve the thermal conductivity. First, exfoliated negatively charged BNNs and positively charged FeCo nanocubes self-assemble to form complex nanomaterials by strong electrostatic interactions. Then, the BNNs can orient with FeCo nanocubes in magnetic field, and the {001} facets of BNNs adsorb on the {100} facets of FeCo nanocubes. The large scale range and high-density FeCo/hBN-aligned structures are observed by scanning electron microscopy, which can act as thermal dissipation channels by conveying more phonons through a preponderant thermally conductive direction. The thermal conductivity of the composite films with 30 wt % FeCo and 50 wt % BN filler is 2.25 W m-1 K-1, 7 times higher than that of the films only containing 50 wt % randomly distributed hBN filler (0.325 W m-1 K-1) and 20 times higher than pure polydimethylsiloxane films (0.114 W m-1 K-1). The thermal management capability of the composite films is evaluated as a thermal conducting substrate of a light-emitting diode chip and the infrared thermal technology. Apart from the surprising thermal conductivity, FeCo-BNNs composite films also exhibit superb flexibility.

13.
ACS Appl Mater Interfaces ; 11(3): 3231-3240, 2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30588790

RESUMO

Stretchable wiring and stretchable bonding between a rigid chip/component and a stretchable substrate are two key factors for stretchable electronics. In this study, a highly conductive stretchable paste has been developed with commercial Ag microflakes and poly(dimethylsiloxane), which can be used to fabricate stretchable wirings and bondings under a low curing temperature of 100 °C with printing method. Herein, recoverabilities as to recovery time and recovery resistance of the wirings are defined and discussed. The effect of Ag composition and the tensile strain rate on the recoverability of the wirings are also examined. The wiring with a low resistivity of 8.7 × 10-5 Ω cm shows much better recoverability than nanowire-based wirings due to the flake nature of the Ag particles. When stretched to 50 and 100% of strain, the resistance of the patterned wiring increases by only 10 and 110%, respectively. Moreover, the resistance of the wiring during 20% tensile cyclic test remains within 1.1 times even after 1000 cycles, thus demonstrating significant durability. The paste was utilized to fabricate conductive tracks and stretchable bondings to assemble a rigid chip to fabricate a stretchable demo. When stretched to 50% of strain, resistance of the wiring was increased by 90%. It is anticipated that the newly developed paste will be used to fabricate various stretchable wirings, bondings, and packaging structures by a simple printing process, thus enabling mass production of stretchable electronic devices.

14.
Clinics ; 74: e1077, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1039556

RESUMO

OBJECTIVES: This study investigated whether tissue Doppler imaging parameters, especially the peak systolic velocity of the left ventricular lead-implanted segment (Ss), affect cardiac resynchronization therapy response. METHODS: In this case-control study, 110 enrolled patients were divided into cases (responder group, n=65) and controls (nonresponder group, n=45) based on whether their left ventricular end-systolic volume was reduced by ≥15% at 6 months after surgery. Preoperative clinical and echocardiographic data were collected. Multivariate logistic regression models were used to analyze the factors affecting the response to cardiac resynchronization therapy, and receiver operating characteristic curves were plotted to evaluate their diagnostic values. RESULTS: The proportion of patients with left bundle branch block in the case group was higher than that in the control group. The control group showed a higher left atrial volume index, E/A ratio and E/Em ratio but lower Ss than that of the case group. A multivariate regression analysis showed that left bundle branch block, Ss, and an E/Em ratio>14 were independent risk factors affecting the response to cardiac resynchronization therapy. Ss=4.1 cm/s was the best diagnostic threshold according to the receiver operating characteristic curve. CONCLUSIONS: Ss is an important factor affecting the response to cardiac resynchronization therapy. Patients with heart failure associated with Ss<4.1 cm/s have a higher risk of nonresponse.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Ecocardiografia Doppler/métodos , Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca/terapia , Ventrículos do Coração/diagnóstico por imagem , Volume Sistólico/fisiologia , Estudos de Casos e Controles , Estudos Retrospectivos , Curva ROC , Resultado do Tratamento , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia
15.
Plant Cell ; 30(10): 2286-2307, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30309900

RESUMO

Sorghum (Sorghum bicolor) is the fifth most popular crop worldwide and a C4 model plant. Domesticated sorghum comes in many forms, including sweet cultivars with juicy stems and grain sorghum with dry, pithy stems at maturity. The Dry locus, which controls the pithy/juicy stem trait, was discovered over a century ago. Here, we found that Dry gene encodes a plant-specific NAC transcription factor. Dry was either deleted or acquired loss-of-function mutations in sweet sorghum, resulting in cell collapse and altered secondary cell wall composition in the stem. Twenty-three Dry ancestral haplotypes, all with dry, pithy stems, were found among wild sorghum and wild sorghum relatives. Two of the haplotypes were detected in domesticated landraces, with four additional dry haplotypes with juicy stems detected in improved lines. These results imply that selection for Dry gene mutations was a major step leading to the origin of sweet sorghum. The Dry gene is conserved in major cereals; fine-tuning its regulatory network could provide a molecular tool to control crop stem texture.


Assuntos
Variação Genética , Proteínas de Plantas/genética , Sorghum/genética , Fatores de Transcrição/genética , Parede Celular/genética , Parede Celular/metabolismo , Grão Comestível/genética , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Estudo de Associação Genômica Ampla , Haplótipos , Proteínas de Plantas/metabolismo , Caules de Planta/fisiologia , Seleção Genética , Sorghum/fisiologia
16.
ACS Appl Mater Interfaces ; 10(42): 36128-36135, 2018 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-30256082

RESUMO

In industrial manufacturing, alloying can contribute to the passivation of active metals and markedly improve their corrosion resistance. This inspires us to solve the current critical problem of Ag nanowires (Ag NWs) that have poor stability against chemical and electrochemical corrosion. These problems have seriously limited the applications of Ag NWs in optoelectronic devices where they are used for transparent conductive electrodes. Here, a kind of transparent conductive electrode based on Ag@Pt alloy-walled hollow nanowires (Ag@Pt AHNWs) is successfully fabricated by introducing 12 mol % Pt into long Ag NWs to form Ag@Pt alloy. The as-synthesized electrodes exhibit better optical transmittance (82% at the wavelength of 550 nm) under high electrical conductivity (28.73 Ω/sq-1), high thermal stability up to 400 °C for 11 h, and remarkable mechanical flexibility (remaining stable after 5000 cycles bending), as well as high resistance against chemical and electrochemical corrosion. The Ag@Pt AHNWs electrodes are further applied in a primary bifunctional polyaniline electrochemical device, and the device shows promising flexibility, noticeable multicolor performances, and high specific capacitance because of the remarkable mechanical flexibility and electrochemical stability of Ag@Pt AHNWs. This work will provide an optional approach for the preparation of other metal nanomaterial electrodes with high stability.

17.
Artigo em Inglês | MEDLINE | ID: mdl-30030191

RESUMO

Desaturase enzymes play an important role in the synthesis of unsaturated fatty acids. In this study, a complete cDNA sequence of a Δ6 desaturase-like gene was cloned from the hepatopancreas of the red claw crayfish, Cherax quadricarinatus. The full-length 1885 bp sequence comprises a 5' UTR of 254 bp, 3' UTR of 234 bp, and an open reading frame (ORF) of 1377 bp encoding a 458 amino acid polypeptide (GenBank accession no. MF497442). Bioinformatics analysis revealed three conserved histidine-rich regions, a cytochrome b5 domain at the N-terminus, and a haem binding site (HPGG) in the cytochrome b5 domain, all of which are typical of Δ6 desaturases. Quantitative real-time PCR demonstrated significantly higher expression in the hepatopancreas than other tissues. After feeding crayfish four formulated diets in which fish oil was replaced by 0, 33, 67, or 100% highly unsaturated soybean oil for 8 weeks, Δ6 desaturase-like mRNA expression and enzyme activity were higher than in the fish oil only group. Additionally, a 4-week low temperature treatment at 25, 20, 15, or 9 °C increased Δ6 desaturase mRNA expression and enzyme activity with decreasing water temperature. These results may help us better understand the biosynthesis of unsaturated fatty acids in C. quadricarinatus.


Assuntos
Astacoidea/genética , Astacoidea/metabolismo , Regulação da Expressão Gênica , Linoleoil-CoA Desaturase/genética , Linoleoil-CoA Desaturase/metabolismo , Temperatura , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Ácidos Graxos Insaturados/biossíntese , Linoleoil-CoA Desaturase/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência
18.
Nanoscale ; 10(11): 5254-5263, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29498383

RESUMO

Cu-Ag complex inks are developed for printing conductive tracks of low cost, high stability, and high conductivity on heat-sensitive substrates such as polyethylene terephthalate (PET) substrates. The inks show an obvious self-catalyzed characteristic due to the in situ formation of fresh metal nanoparticles which promote rapid decomposition and sintering of the inks at a low temperature below 100 °C. The temperature is 40-60 °C lower than those of general Cu complex inks and 100-120 °C lower than those of general Cu/Ag particle inks. Highly conductive Cu-Ag tracks of 2.80 × 10-5 Ω cm and 6.40 × 10-5 Ω cm have been easily realized at 100 °C and 80 °C, respectively. In addition, the printed Cu-based tracks not only show high oxidation resistance at high temperatures of up to 140 °C (the maximum tolerable temperature of current PET substrate) but also show excellent stability at high humidity of 85% because of the very uniform Cu-Ag hybrid structure. The printable tracks exhibit great potential application in various wearable devices fabricated on textiles, papers, and other heat-sensitive substrates.

19.
Materials (Basel) ; 11(2)2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-29473865

RESUMO

This paper is the first to report a large-scale directcurrent electrodeposition of columnar nanotwinned copper within through silicon via (TSV) with a high aspect ratio (~4). With this newly developed technique, void-free nanotwinned copper array could be fabricated in low current density (30 mA/cm²) and convection conditions (300 rpm), which are the preconditions for copper deposition with a uniform deep-hole microstructure. The microstructure of a whole cross-section of deposited copper array was made up of (111) orientated columnar grains with parallel nanoscale twins that had thicknesses of about 22 nm. The hardness was also uniform along the growth direction, with 2.34 and 2.68 GPa for the top and bottom of the TSV, respectively. The gelatin additive is also first reported hereas a key factor in forming nanoscale twins by adsorbing on the cathode surface, in order to enhance the overpotential for cathodic reaction during the copper deposition process.

20.
Front Plant Sci ; 8: 1268, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28775729

RESUMO

The thermo-sensitive genic male sterility (TGMS) line SP2S is a spontaneous rapeseed mutation with several traits that are favorable for the production of two-line hybrids. To uncover the key cellular events and genetic regulation associated with TGMS expression, a combined study using cytological observation, transcriptome profiling, and gene expression analysis was conducted for SP2S and its near-isogenic line SP2F grown under warm conditions. Asynchronous microsporocyte meiosis and abnormal tapetal plastids and elaioplasts were demonstrated in the anther of SP2S. The tetrad microspore did not undergo mitosis before the cytoplasm degenerated. Delayed degradation of the tetrad wall, which led to tetrad microspore aggregation, resulted in postponement of sexine (outer layer of pollen exine) formation and sexine fusion in the tetrad. The nexine (foot layer of exine) was also absent. The delay of tetrad wall degradation and abnormality of the exine structure suggested that the defective tapetum lost important functions. Based on transcriptomic comparisons between young flower buds of SP2S and SP2F plants, a total of 465 differentially expressed transcripts (DETs) were identified, including 303 up-regulated DETs and 162 down-regulated DETs in SP2S. Several genes encoding small RNA degrading nuclease 2, small RNA 2'-O-methyltransferase, thioredoxin reductase 2, regulatory subunit A alpha isoform of serine/threonine-protein phosphatase 2A, glycine rich protein 1A, transcription factor bHLH25, leucine-rich repeat receptor kinase At3g14840 like, and fasciclin-like arabinogalactan proteins FLA19 and FLA20 were greatly depressed in SP2S. Interestingly, a POLLENLESS3-LIKE 2 gene encoding the Arabidopsis MS5 homologous protein, which is necessary for microsporocyte meiosis, was down-regulated in SP2S. Other genes that were up-regulated in SP2S encoded glucanase A6, ethylene-responsive transcription factor 1A-like, pollen-specific SF3, stress-associated endoplasmic reticulum protein 2, WRKY transcription factors and pentatricopeptide repeat (PPR) protein At1g07590. The tapetum-development-related genes, including BnEMS1, BnDYT1, and BnAMS, were slightly up-regulated in 3-mm-long flower buds or their anthers, and their downstream genes, BnMS1 and BnMYB80, which affect callose dissolution and exine formation, were greatly up-regulated in SP2S. This aberrant genetic regulation corresponded well with the cytological abnormalities. The results suggested that expression of TGMS associates with complex transcriptional regulation.

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