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1.
Liver Int ; 44(2): 330-343, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38014574

RESUMO

Metabolic dysfunction-associated fatty liver disease (MAFLD) has reached epidemic proportions worldwide and is the most frequent cause of chronic liver disease in developed countries. Within the spectrum of liver disease in MAFLD, steatohepatitis is a progressive form of liver disease and hepatocyte ballooning (HB) is a cardinal pathological feature of steatohepatitis. The accurate and reproducible diagnosis of HB is therefore critical for the early detection and treatment of steatohepatitis. Currently, a diagnosis of HB relies on pathological examination by expert pathologists, which may be a time-consuming and subjective process. Hence, there has been interest in developing automated methods for diagnosing HB. This narrative review briefly discusses the development of artificial intelligence (AI) technology for diagnosing fatty liver disease pathology over the last 30 years and provides an overview of the current research status of AI algorithms for the identification of HB, including published articles on traditional machine learning algorithms and deep learning algorithms. This narrative review also provides a summary of object detection algorithms, including the principles, historical developments, and applications in the medical image analysis. The potential benefits of object detection algorithms for HB diagnosis (specifically those combined with a transformer architecture) are discussed, along with the future directions of object detection algorithms in HB diagnosis and the potential applications of generative AI on transformer architecture in this field. In conclusion, object detection algorithms have huge potential for the identification of HB and could make the diagnosis of MAFLD more accurate and efficient in the near future.


Assuntos
Inteligência Artificial , Hepatopatia Gordurosa não Alcoólica , Humanos , Algoritmos , Tecnologia , Hepatócitos
2.
Angew Chem Int Ed Engl ; : e202405408, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728168

RESUMO

Ring-opening polymerization (ROP) offers a striking solution to solve problems encountered in step-growth condensation polymerization, including precise control over molecular weight, molecular weight distribution, and topology. This has inspired our interest in ROP of cycloalkanes with an ultimate goal to rethink polyolefins, which clearly poses a number of challenges. Practicality of ROP of cycloalkanes is actually limited by their low polymerizability and elusive mechanisms which arise from significantly varied ring size and non-polar C-C bonds in monomers. In this work, by using Lewis acid/Brønsted base/C(sp3)-H initiator system previously developed in our laboratory, we focus on cyclobutanes and explore the positional and electronic effects of substituents on the ring, namely electron push-pull effect, in promoting controlled polymerization to afford densely functionalized poly(cyclobutanes), as well as catalytic degradation of obtained polymers for upcycling. More importantly, experiments and DFT calculations unveil considerable population of Lewis-acid-induced thermostabilized 1,4-zwitterions, which distinguish cyclobutanes from cyclopropanes and others. All these findings would shed light on catalytic synthesis and degradation of saturated all-carbon main-chain polymers, as well as small molecule transformations of cyclobutanes.

3.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(3): 262-268, 2024 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-38557378

RESUMO

OBJECTIVES: To investigate the factors influencing the occurrence of small for gestational age (SGA) at different degrees and provide a basis for early identification of severe SGA cases. METHODS: Neonatal and maternal prenatal information were retrospectively collected from January 2018 to December 2022 at Peking University People's Hospital. The neonates were divided into three groups: severe SGA group (birth weight below the 3rd percentile for gestational age and sex), mild SGA group (birth weight ≥3rd percentile and <10th percentile), and non-SGA group (birth weight ≥10th percentile). An ordered multinomial logistic regression model was used to analyze the factors influencing the occurrence of SGA at different degrees. RESULTS: A total of 14 821 neonates were included, including 258 cases (1.74%) in the severe SGA group, 902 cases (6.09%) in the mild SGA group, and 13 661 cases (92.17%) in the non-SGA group. The proportions of preterm births and stillbirths were higher in the severe SGA group compared to the mild SGA and non-SGA groups (P<0.0125). The proportion of neonatal asphyxia was higher in both the severe SGA and mild SGA groups compared to the non-SGA group (P<0.0125). Ordered multinomial logistic regression analysis showed that maternal pre-pregnancy underweight (OR=1.838), maternal pre-pregnancy obesity (OR=3.024), in vitro fertilization-embryo transfer (OR=2.649), preeclampsia (OR=1.743), connective tissue disease during pregnancy (OR=1.795), nuchal cord (OR=1.213), oligohydramnios (OR=1.848), and intrauterine growth restriction (OR=27.691) were all associated with a higher risk of severe SGA (P<0.05). Maternal parity as a multipara (OR=0.457) was associated with a lower likelihood of severe SGA (P<0.05). CONCLUSIONS: Maternal pre-pregnancy underweight, maternal pre-pregnancy obesity, in vitro fertilization-embryo transfer, preeclampsia, connective tissue disease during pregnancy, oligohydramnios, nuchal cord, and intrauterine growth restriction are closely related to the occurrence of more severe SGA. Maternal parity as a multipara acts as a protective factor against the occurrence of severe SGA.


Assuntos
Doenças do Tecido Conjuntivo , Cordão Nucal , Oligo-Hidrâmnio , Pré-Eclâmpsia , Gravidez , Recém-Nascido , Feminino , Humanos , Retardo do Crescimento Fetal , Peso ao Nascer , Idade Gestacional , Estudos Retrospectivos , Magreza , Recém-Nascido Pequeno para a Idade Gestacional , Obesidade
4.
Small ; 19(37): e2301715, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37144443

RESUMO

Electrocatalysts based on Fe and other transition metals are regarded as most promising candidates for accelerating the oxygen evolution reaction (OER), whereas whether Fe is the catalytic active site for OER is still under debate. Here, unary Fe- and binary FeNi- based catalysts, FeOOH and FeNi(OH)x , are produced by self-reconstruction. The former is a dual-phased FeOOH, possessing abundant oxygen vacancies (VO ) and mixed-valence states, delivering the highest OER performance among all the unary iron oxides- and hydroxides- based powder catalysts reported to date, supporting Fe can be catalytically active for OER. As to binary catalyst, FeNi(OH)x is fabricated featuring 1) an equal molar content of Fe and Ni and 2) rich VO , both of which are found essential to enable abundant stabilized reactive centers (FeOOHNi) for high OER performance. Fe is found to be oxidized to 3.5+ during the *OOH process, thus, Fe is identified to be the active site in this new layered double hydroxide (LDH) structure with Fe:Ni = 1:1. Furthermore, the maximized catalytic centers enable FeNi(OH)x @NF (nickel foam) as low-cost bifunctional electrodes for overall water-splitting, delivering excellent performance comparable to commercial electrodes based on precious metals, which overcomes a major obstacle to the commercialization of bifunctional electrodes: prohibitive cost.

5.
Liver Int ; 43(6): 1170-1182, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37017559

RESUMO

Hepatocytic ballooning is a key histological feature in the diagnosis of non-alcoholic steatohepatitis (NASH) and is an essential component of the two most widely used histological scoring systems for diagnosing and staging non-alcoholic fatty liver disease (NAFLD) [namely, the NAFLD activity score (NAS), and the steatosis, activity and fibrosis (SAF) scoring system]. As a result of the increasing incidence of NASH globally, the diagnostic challenges of hepatocytic ballooning are unprecedented. Despite the clear pathological concept of hepatocytic ballooning, there are still challenges in assessing hepatocytic ballooning in 'real life' situations. Hepatocytic ballooning can be confused with cellular oedema and microvesicular steatosis. Significant inter-observer variability does exist in assessing the presence and severity of hepatocytic ballooning. In this review article, we describe the underlying mechanisms associated with hepatocytic ballooning. Specifically, we discuss the increased endoplasmic reticulum stress and the unfolded protein response, as well as the rearrangement of the intermediate filament cytoskeleton, the appearance of Mallory-Denk bodies and activation of the sonic Hedgehog pathway. We also discuss the use of artificial intelligence in the detection and interpretation of hepatocytic ballooning, which may provide new possibilities for future diagnosis and treatment.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Fígado/patologia , Inteligência Artificial , Proteínas Hedgehog , Índice de Gravidade de Doença , Biópsia
6.
Am J Addict ; 32(6): 593-605, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37615548

RESUMO

BACKGROUND AND OBJECTIVES: Addictive behaviors are serious factors for mental health and usually increase during public crises. We identified the vulnerable characteristics for bad prognosis of addictive internet use across different periods of the coronavirus disease 2019 (COVID-19) pandemic. METHODS: Self-reported questionnaires were delivered in three waves through jdh.com during the outbreak (n = 17,960), remission (n = 15,666), and dynamic zero (n = 12,158) periods of COVID-19 pandemic in China. Internet addiction degree was assessed using the Internet Addiction Test. The different progression groups were divided using a latent class growth model among 1679 longitudinal participants. Risk factors for bad progression were identified by two-step logistic regression. RESULTS: A total of 40.16% of participants reported an increase in the addictive degree of internet use compared with prepandemic. Across different COVID-19 periods, the overall trend of addictive internet use was downward among general Chinese study participants (Mslope = -1.56). Childhood traumatic experiences, deterioration of physical health, depression, and anxiety during remission and dynamic periods were the main risk factors for the bad progression of pandemic-induced addictive internet use. DISCUSSION AND CONCLUSIONS: Addictive internet use was remitted following relaxed control policies during the COVID-19 pandemic. Negative childhood experiences and bad mental status during the recovery period were harmful to coping with pandemic-related addictive internet use. SCIENTIFIC SIGNIFICANCE: Our findings profiled the general trend of addictive internet use and the vulnerable characteristics of its bad progression across different periods of the first wave of COVID-19 pandemic in China. Our findings provide valuable insights for preventing the long-term adverse effects of negative public events on Internet addiction.


Assuntos
Comportamento Aditivo , COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias , Uso da Internet , Comportamento Aditivo/epidemiologia , Comportamento Aditivo/psicologia , Fatores de Risco , China/epidemiologia , Internet
7.
Sensors (Basel) ; 23(6)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36991919

RESUMO

Glucose sensors based blood glucose detection are of great significance for the diagnosis and treatment of diabetes because diabetes has aroused wide concern in the world. In this study, bovine serum albumin (BSA) was used to cross-link glucose oxidase (GOD) on a glassy carbon electrode (GCE) modified by a composite of hydroxy fullerene (HFs) and multi-walled carbon nanotubes (MWCNTs) and protected with a glutaraldehyde (GLA)/Nafion (NF) composite membrane to prepare a novel glucose biosensor. The modified materials were analyzed by UV-visible spectroscopy (UV-vis), transmission electron microscopy (TEM), and cyclic voltammetry (CV). The prepared MWCNTs-HFs composite has excellent conductivity, the addition of BSA regulates MWCNTs-HFs hydrophobicity and biocompatibility, and better immobilizes GOD on MWCNTs-HFs. MWCNTs-BSA-HFs plays a synergistic role in the electrochemical response to glucose. The biosensor shows high sensitivity (167 µA·mM-1·cm-2), wide calibration range (0.01-3.5 mM), and low detection limit (17 µM). The apparent Michaelis-Menten constant Kmapp is 119 µM. Additionally, the proposed biosensor has good selectivity and excellent storage stability (120 days). The practicability of the biosensor was evaluated in real plasma samples, and the recovery rate was satisfactory.


Assuntos
Técnicas Biossensoriais , Nanocompostos , Nanotubos de Carbono , Glucose/química , Nanotubos de Carbono/química , Glucose Oxidase/química , Soroalbumina Bovina/química , Técnicas Biossensoriais/métodos , Eletrodos , Nanocompostos/química , Enzimas Imobilizadas/química , Técnicas Eletroquímicas/métodos
8.
Nano Lett ; 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36190454

RESUMO

Plasmon-mediated chemical reactions have attracted intensive research interest as a means of achieving desirable reaction yields and selectivity. The energetic charge carriers and elevated local temperature induced by the nonradiative decay of surface plasmons are thought to be responsible for improving reaction outcomes. This study reports that the plasmoelectric potential is another key contributor in plasmon-mediated electrochemistry. Additionally, we disclose a convenient and reliable method for quantifying the specific contributions of the plasmoelectric potential, hot electrons, and photothermal heating to the electroreduction of oxygen at the plasmonic Ag electrode, revealing that the plasmoelectric potential is the dominating nonthermal factor under short-wavelength illumination and moderate electrode bias. This work elucidates novel mechanistic understandings of plasmon-mediated electrochemistry, facilitating high-performance plasmonic electrocatalyst design optimization.

9.
Nano Lett ; 22(2): 822-829, 2022 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-35029994

RESUMO

The structural and mechanical properties of low-dimensional nanostructured metals have been attracting tremendous interest in the fast-growing fields of nanosciences and nanotechnologies. However, it still remains a challenge today to develop strong yet ductile low-dimensional metals that can support the further development of nanodevices. Here, through the polymer-assisted assembly of gold nanocrystals, we successfully fabricated the freestanding, ultrathin gold nanomaterial. Unlike conventional bulk gold or other low-dimensional gold nanostructures (i.e., nanowires and nanosheets), these gold nanosheets are composed of highly distorted gold nanocrystals that are 3-5 nm in size, which are joined together through nanosized amorphous carbon interphases. As a result, the gold nanosheets exhibit superb strength (up to 1.2 GPa), excellent ductility (>50%), and superior fracture toughness (>100 J/m2), outperforming various gold nanostructures hitherto reported.


Assuntos
Nanopartículas , Nanoestruturas , Ouro , Nanoestruturas/química , Resistência à Tração
10.
Plant Physiol ; 186(3): 1706-1720, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-33871656

RESUMO

In plants, reactive oxygen species (ROS) produced following the expression of the respiratory burst oxidase homolog (Rboh) gene are important regulators of stress responses. However, little is known about how plants acclimate to salt stress through the Rboh-derived ROS signaling pathway. Here, we showed that a 400-bp fragment of the tobacco (Nicotiana tabacum) NtRbohE promoter played a critical role in the salt response. Using yeast one-hybrid (Y1H) screens, NtbHLH123, a bHLH transcription factor, was identified as an upstream partner of the NtRbohE promoter. These interactions were confirmed by Y1H, electrophoretic mobility assay, and chromatin immunoprecipitation assays. Overexpression of NtbHLH123 resulted in greater resistance to salt stress, while NtbHLH123-silenced plants had reduced resistance to salt stress. We also found that NtbHLH123 positively regulates the expression of NtRbohE and ROS production soon after salt stress treatment. Moreover, knockout of NtRbohE in the 35S::NtbHLH123 background resulted in reduced expression of ROS-scavenging and salt stress-related genes and salt tolerance, suggesting that NtbHLH123-regulated salt tolerance is dependent on the NtbHLH123-NtRbohE signaling pathway. Our data show that NtbHLH123 is a positive regulator and acts as a molecular switch to control a Rboh-dependent mechanism in response to salt stress in plants.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Tolerância ao Sal/genética , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Plantas Geneticamente Modificadas , Espécies Reativas de Oxigênio/metabolismo
11.
Nutr Metab Cardiovasc Dis ; 32(5): 1259-1265, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35260312

RESUMO

BACKGROUND AND AIMS: Zinc is an essential trace element that plays an important role in maintaining health, and affecting gene expression, signal transduction and regulation of apoptosis. It is uncertain whether serum zinc levels are altered in patients with metabolic dysfunction-associated fatty liver disease (MAFLD). We aimed to investigate the association between serum zinc levels and the severity of hepatic necro-inflammation (HN) in patients with MAFLD. METHODS AND RESULTS: Liver disease severity was graded histologically using the NAFLD activity score. HN was defined as the sum of ballooning and lobular inflammation. We used a smooth function regression model to analyze the relationship between serum zinc levels and HN. A total of 561 (76.5% men) patients with biopsy-confirmed MAFLD were enrolled. They had a mean age of 41.3 years, and a mean serum zinc level of 17.0 ± 4.1 µmol/L. Compared to those with mild hepatic necro-inflammation (MHN, grades 0-2; n = 286), patients with severe hepatic necro-inflammation (SHN, grades 3-5; n = 275) had lower serum zinc concentrations (16.3 ± 4.2 vs. 17.6 ± 4.0 µmol/L; p < 0.001). However, a threshold saturation effect analysis showed that there was an inflection in serum zinc levels at 24 µmol/L. After adjustment for potential confounders, serum zinc levels <24 µmol/L were inversely associated with SHN (adjusted-odds ratio 0.88, 95%CI 0.83-0.93; p < 0.001), whereas serum zinc levels >24 µmol/L were positively associated with SHN (adjusted-odds ratio 1.42, 95%CI: 1.03-1.97; p = 0.035). CONCLUSIONS: There is a J-shaped relationship between serum zinc levels and the severity of hepatic necro-inflammation in patients with biopsy-proven MAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Adulto , Feminino , Humanos , Inflamação/diagnóstico , Cirrose Hepática , Masculino , Hepatopatia Gordurosa não Alcoólica/complicações , Zinco
12.
Small ; 17(8): e2006373, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33522133

RESUMO

Up to now, the silicon-graphite anode materials with commercial prospect for lithium batteries (LIBs) still face three dilemmas of the huge volume effect, the poor interface compatibility, and the high resistance. To address the above challenges, micro-nano structured composites of graphite coating by ZnO-incorporated and carbon-coated silicon (marked as Gr@ZnO-Si-C) are reasonably synthesized via an efficient and convenient method of liquid phase self-assembly synthesis combined with annealing treatment. The designed composites of Gr@ZnO-Si-C deliver excellent lithium battery performance with good rate performance and stable long-cycling life of 1000 cycles with reversible capacities of 1150 and 780 mAh g-1 tested at 600 and 1200 mA g-1 , respectively. The obtained results reveal that the incorporated ZnO effectively improve the interface compatibility between electrolyte and active materials, and boost the formation of compact and stable surface solid electrolyte interphase layer for electrodes. Furthermore, the pyrolytic carbon layer formed from polyacrylamide can directly improve electrical conductivity, decrease polarization, and thus promote their electrochemical performance. Finally, based on the scalable preparation of Gr@ZnO-Si-C composites, the pouch full cells of Gr@ZnO-Si-C||NCM523 are assembled and used to evaluate the commercial prospects of Si-graphite composites, offering highly useful information for researchers working in the battery industry.

13.
Br J Nutr ; 126(6): 813-824, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-33198849

RESUMO

The FNDC5 gene encodes the fibronectin type III domain-containing protein 5 that is a membrane protein mainly expressed in skeletal muscle, and the FNDC5 rs3480 polymorphism may be associated with liver disease severity in non-alcoholic fatty liver disease (NAFLD). We investigated the influence of the FNDC5 rs3480 polymorphism on the relationship between sarcopenia and the histological severity of NAFLD. A total of 370 adult individuals with biopsy-proven NAFLD were studied. The association between the key exposure sarcopenia and the outcome liver histological severity was investigated by binary logistic regression. Stratified analyses were undertaken to examine the impact of FNDC5 rs3480 polymorphism on the association between sarcopenia and the severity of NAFLD histology. Patients with sarcopenia had more severe histological grades of steatosis and a higher prevalence of significant fibrosis and definite non-alcoholic steatohepatitis than those without sarcopenia. There was a significant association between sarcopenia and significant fibrosis (adjusted OR 2·79, 95 % CI 1·31, 5·95, P = 0·008), independent of established risk factors and potential confounders. Among patients with sarcopenia, significant fibrosis occurred more frequently in the rs3480 AA genotype carriers than in those carrying the FNDC5 rs3480 G genotype (43·8 v. 17·2 %, P = 0·031). In the association between sarcopenia and liver fibrosis, there was a significant interaction between the FNDC5 genotype and sarcopenia status (P value for interaction = 0·006). Sarcopenia is independently associated with significant liver fibrosis, and the FNDC5 rs3480 G variant influences the association between sarcopenia and liver fibrosis in patients with biopsy-proven NAFLD.


Assuntos
Fibronectinas , Hepatopatia Gordurosa não Alcoólica , Sarcopenia , Adulto , Biópsia , Fibronectinas/genética , Humanos , Fígado/patologia , Cirrose Hepática/genética , Cirrose Hepática/patologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Sarcopenia/genética
14.
Am J Addict ; 30(4): 389-397, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33738888

RESUMO

BACKGROUND AND OBJECTIVES: COVID-19-related quarantine and stress have likely escalated the crisis of Internet addiction. This study aimed to determine the impact of the COVID-19 pandemic on Internet use and related risk factors among the general public in China. METHODS: A large-sample cross-sectional online survey was conducted from March 24 to April 30, 2020, in China, and 20,472 participants completed the survey. We investigated the prevalence and severity of Internet addiction based on the Internet Addiction Test (IAT), and explored the risk factors related to increases in time spent on Internet use and severity of Internet addiction, as well as severe Internet addiction. RESULTS: The overall prevalence of Internet addiction was 36.7% among the general population during the pandemic, and that of severe Internet addiction was 2.8%, according to IAT scores. Time spent on recreational Internet use had significantly increased during the pandemic, and almost half of participants reported increases in the severity of Internet addiction. Risk factors for increases in time spent on Internet use and severity of Internet addiction and severe Internet addiction included having fewer social supporters, perceiving pressure and impact on mental health status due to COVID-19, and being over-engaged in playing videogames. DISCUSSION AND CONCLUSIONS: The COVID-19 pandemic adversely impacted Internet use and increased the prevalence and severity of Internet addiction among the general population in China, especially in vulnerable populations. SCIENTIFIC SIGNIFICANCE: This study provides evidence for policymakers to refine public health policies to control the pandemic and make efforts to provide population-specific prevention and interventions for people at risk of developing Internet addiction. (Am J Addict 2021;00:00-00).


Assuntos
Comportamento Aditivo/psicologia , COVID-19/psicologia , Transtorno de Adição à Internet/epidemiologia , Adolescente , Adulto , Comportamento Aditivo/epidemiologia , COVID-19/epidemiologia , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Internet , Transtorno de Adição à Internet/psicologia , Masculino , Pessoa de Meia-Idade , Pandemias , Prevalência , Fatores de Risco , SARS-CoV-2 , Inquéritos e Questionários , Adulto Jovem
15.
Hepatobiliary Pancreat Dis Int ; 20(5): 452-459, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34256994

RESUMO

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is one of the main liver diseases, and its pathologic profile includes nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH). However, there is no reliable non-invasive parameter in distinguishing NASH from NAFL in clinical practice. The present study was to find a non-invasive way to differentiate these two categories of NAFLD via lipidomic analysis. METHODS: Lipidomic analysis was used to determine the changes of lipid moieties in blood from 20 NAFL and 10 NASH patients with liver biopsy. Liver histology was evaluated after hematoxylin and eosin staining and Masson's trichrome staining. The profile of lipid metabolites in correlation with steatosis, inflammation, hepatocellular necroptosis, fibrosis, and NAFLD activity score (NAS) was analyzed. RESULTS: Compared with NAFL patients, NASH patients had higher degree of steatosis, ballooning degeneration, lobular inflammation. A total of 434 different lipid molecules were identified, which were mainly composed of various phospholipids and triacylglycerols. Many lipids, such as phosphatidylcholine (PC) (P-22:0/18:1), sphingomyelin (SM) (d14:0/18:0), SM (d14:0/24:0), SM (d14:0/22:0), phosphatidylethanolamine (PE) (18:0/22:5), PC (O-22:2/12:0), and PC (26:1/11:0) were elevated in the NASH group compared to those in the NAFL group. Specific analysis revealed an overall lipidomic profile shift from NAFL to NASH, and identified valuable lipid moieties, such as PCs [PC (14:0/18:2), PE (18:0/22:5) and PC (26:1/11:0)] or plasmalogens [PC (O-22:0/0:0), PC (O-18:0/0:0), PC (O-16:0/0:0)], which were significantly altered in NASH patients. In addition, PC (14:0/18:2), phosphatidic acid (18:2/24:4) were positively correlated with NAS; whereas PC (18:0/0:0) was correlated positively with fibrosis score. CONCLUSIONS: The present study revealed overall lipidomic profile shift from NAFL to NASH, identified valuable lipid moieties which may be non-invasive biomarkers in the categorization of NAFLD. The correlations between lipid moieties and NAS and fibrosis scores indicate that these lipid biomarkers may be used to predict the severity of the disease.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Biomarcadores , Cromatografia Líquida , Fibrose , Humanos , Inflamação , Lipidômica , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/patologia , Fosfolipídeos , Espectrometria de Massas em Tandem
16.
Biochem Biophys Res Commun ; 522(1): 233-239, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31757426

RESUMO

Iron (Fe) is a major micronutrient which influences plant growth, development, quality and yield. Although basic helix-loop-helix (bHLH) transcription factors (TFs) which respond to iron deficiency have been identified, the molecular mechanisms have not been fully elucidated. In this study, a novel bHLH TF, NtbHLH1, was found to be induced by iron deficiency. Further analysis indicated that NtbHLH1 is localized to the nucleus and functions as a transcriptional activator. Moreover, overexpression of NtbHLH1 resulted in longer roots, altered rhizosphere pH and increased ferric-chelate reductase activity in iron deficient conditions. Overall these changes resulted in increased iron uptake relative to wild type plants. NtbHLH1 mutants, on the other hand, had an opposite phenotype. In addition, transcript levels of seven genes associated with iron deficiency response were higher in the NtbHLH1 overexpression transgenic plants and lower in ntbhlh1 relative to the WT under iron deficiency treatment. Taken together, these results demonstrated that NtbHLH1 plays a key role in iron deficiency response and they provide new insights into the molecular basis of iron homeostasis in tobacco.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Regulação da Expressão Gênica de Plantas , Ferro/metabolismo , Nicotiana/metabolismo , Proteínas de Plantas/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Homeostase , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Nicotiana/genética , Regulação para Cima
17.
Planta ; 252(1): 13, 2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32621079

RESUMO

MAIN CONCLUSION: NtALS1 is specifically expressed in glandular trichomes, and can improve the content of acylsugars in tobacco. ABTRACT: The glandular trichomes of many species in the Solanaceae family play an important role in plant defense. These epidermal outgrowths exhibit specialized secondary metabolism, including the production of structurally diverse acylsugars that function in defense against insects and have substantial developmental potential for commercial uses. However, our current understanding of genes involved in acyl chain biosynthesis of acylsugars remains poor in tobacco. In this study, we identified three acetolactate synthase (ALS) genes in tobacco through homology-based gene prediction using Arabidopsis ALS. Quantitative real-time PCR (qRT-PCR) and tissue distribution analyses suggested that NtALS1 was highly expressed in the tips of glandular trichomes. Subcellular localization analysis showed that the NtALS1 localized to the chloroplast. Moreover, in the wild-type K326 variety background, we generated two ntals1 loss-of-function mutants using the CRISPR-Cas9 system. Acylsugars contents in the two ntals1 mutants were significantly lower than those in the wild type. Through phylogenetic tree analysis, we also identified NtALS1 orthologs that may be involved in acylsugar biosynthesis in other Solanaceae species. Taken together, these findings indicate a functional role for NtALS1 in acylsugar biosynthesis in tobacco.


Assuntos
Acetolactato Sintase/genética , Nicotiana/metabolismo , Açúcares/metabolismo , Tricomas/enzimologia , Acetolactato Sintase/metabolismo , Proteínas de Arabidopsis/genética , Sistemas CRISPR-Cas , Cloroplastos/enzimologia , Diploide , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Nicotiana/genética , Tricomas/genética
18.
Plant Biotechnol J ; 18(12): 2444-2455, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32445603

RESUMO

Drought stress often limits plant growth and global crop yields. Catalase (CAT)-mediated hydrogen peroxide (H2 O2 ) scavenging plays an important role in the adaptation of plant stress responses, but the transcriptional regulation of the CAT gene in response to drought stress is not well understood. Here, we isolated an APETALA2/ETHYLENE-RESPONSIVE FACTOR (AP2/ERF) domain-containing transcription factor (TF), NtERF172, which was strongly induced by drought, abscisic acid (ABA) and H2 O2 , from tobacco (Nicotiana tabacum) by yeast one-hybrid screening. NtERF172 localized to the nucleus and acted as a transcriptional activator. Chromatin immunoprecipitation, yeast one-hybrid assays, electrophoretic mobility shift assays and transient expression analysis assays showed that NtERF172 directly bound to the promoter region of the NtCAT gene and positively regulated its expression. Transgenic plants overexpressing NtERF172 displayed enhanced tolerance to drought stress, whereas suppression of NtERF172 decreased drought tolerance. Under drought stress conditions, the NtERF172-overexpressed lines showed higher catalase activity and lower accumulation of H2 O2 compared with wild-type (WT) plants, while the NtERF172-silenced plants showed the inverse correlation. Exogenous application of amino-1,2,4-triazole (3-AT), an irreversible CAT inhibitor, to the NtERF172-overexpression lines showed decreased catalase activity and drought tolerance, and increased levels of cellular H2 O2 . Knockdown of NtCAT in the NtERF172-overexpression lines displayed a more drought stress-sensitive phenotype than NtERF172-overexpression lines. We propose that NtERF172 acts as a positive factor in drought stress tolerance, at least in part through the regulation of CAT-mediated H2 O2 homeostasis.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Ácido Abscísico , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico , Fatores de Transcrição/genética
19.
Inorg Chem ; 59(8): 5626-5631, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32233407

RESUMO

Finely dispersed Co(0) and CoO species were efficiently loaded into a stable metal-organic framework to impart catalytic activities to the porous solid. The metalation of the MOF host is facilitated by the dense arrays of accessible alkyne units that boost the alkyne-Co2(CO)8 interaction. The tetrakis(4-carboxylphenylethynyl)pyrene linker, with eight symmetrically backfolded alkyne side arms, features strong fluorescence and a dendritic Sierpinski shape. The resultant Zr(IV)-MOF features NU-901 topology (scu net, with rhombus channels) and breathing properties (e.g., the contracted (porous) phase reverts to the as-made phase upon contact with DMF (dimethylformamide)). The inserted Co2(CO)8 guests quickly react with air to form atomically dispersed CoO species (nondiffracting), and subsequent thermal treatment at 600 °C of the CoO-loaded solid generates an electrocatalyst for the oxygen evolution reaction (OER).

20.
J Gastroenterol Hepatol ; 35(10): 1804-1812, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32246876

RESUMO

BACKGROUND AND AIM: There is an immediate need for non-invasive accurate tests for diagnosing liver fibrosis in patients with non-alcoholic steatohepatitis (NASH). Previously, it has been suggested that MACK-3 (a formula that combines homeostasis model assessment-insulin resistance with serum serum aspartate aminotransferase and cytokeratin [CK]18-M30 levels) accurately identifies patients with fibrotic NASH. Our aim was to assess the performance of MACK-3 and develop a novel, non-invasive algorithm for diagnosing fibrotic NASH. METHODS: Six hundred and thirty-six adults with biopsy-proven non-alcoholic fatty liver disease (NAFLD) from two independent Asian cohorts were enrolled in our study. Liver stiffness measurement (LSM) was assessed by vibration-controlled transient elastography (Fibroscan). Fibrotic NASH was defined as NASH with a NAFLD activity score (NAS) ≥ 4 and F ≥ 2 fibrosis. RESULTS: Metabolic syndrome (MetS), platelet count and MACK-3 were independent predictors of fibrotic NASH. On the basis of their regression coefficients, we developed a novel nomogram showing a good discriminatory ability (area under receiver operating characteristic curve [AUROC]: 0.79, 95% confidence interval [CI 0.75-0.83]) and a high negative predictive value (NPV: 94.7%) to rule out fibrotic NASH. In the validation set, this nomogram had a higher AUROC (0.81, 95%CI 0.74-0.87) than that of MACK-3 (AUROC: 0.75, 95%CI 0.68-0.82; P < 0.05) with a NPV of 93.2%. The sequential combination of this nomogram with LSM data avoided the need for liver biopsy in 56.9% of patients. CONCLUSIONS: Our novel nomogram (combining MACK-3, platelet count and MetS) shows promising utility for diagnosing fibrotic NASH. The sequential combination of this nomogram and vibration-controlled transient elastography limits indeterminate results and reduces the number of unnecessary liver biopsies.


Assuntos
Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Adulto , Algoritmos , Povo Asiático , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Biópsia , Estudos de Coortes , Técnicas de Imagem por Elasticidade , Feminino , Fibrose , Humanos , Resistência à Insulina , Queratina-18/sangue , Masculino , Síndrome Metabólica , Pessoa de Meia-Idade , Nomogramas , Hepatopatia Gordurosa não Alcoólica/patologia , Contagem de Plaquetas , Curva ROC
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