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1.
Nutr Bull ; 49(2): 146-156, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38363028

RESUMO

We aimed to explore and analyse the dietary intake patterns of 3-6 year-old children left behind by one or both parents and to assess their associations with body mass index (BMI) and the prevalence of childhood anaemia in rural Anhui, eastern China. We used random cluster sampling to recruit rural children aged 3-6 years in two rural areas in Anhui province. Sociodemographic information and dietary intake were collected by self-reported questionnaires. Height, weight and prevalence of anaemia were measured by trained nurses blinded to parental migration status. Factor analysis was applied to determine that major dietary patterns, binary logistic regression and generalised linear regression were used to explore the associations between anaemia and BMI Z-score with dietary patterns. Of 1720 children aged 3-6 years, 236 were left by both parents and 388 were left by a single parent. The prevalence of stunting and underweight among left-behind children with migration of both parents (BLBC) was significantly higher than that of non-left-behind children (NLBC). Three dietary patterns-"grain-vegetable," "meat-egg" and "fast food-sweet"-were identified in our study, and the total variance explained was 46.9%. The meat-egg dietary pattern was associated with a decreased risk of anaemia after adjustment for confounding factors in the left-behind children with migration of both parents (BLBC), left-behind children with single parent migration (SLBC) and non-left-behind children (NLBC) groups. After adjusting for confounding factors, the fast food-sweet dietary pattern was found to be associated with an increased risk of anaemia (OR [95% CI]: Q4: 2.21 [1.14, 4.57], p = 0.034). In addition, children with obesity had a lower intake of vegetables and fruits (ß = -0.08, 95% CI: -0.13, -0.02) compared with children with a normal weight. In conclusion, there are correlations between different types of parental migration and children's nutritional status in rural Anhui. The meat-egg dietary pattern may have a preventive effect on anaemia in comparison with other dietary patterns, irrespective of whether children are left behind or not. Children with overweight and obesity had a higher intake of pork and red meat and snacks compared with children with normal BMI.


Assuntos
Anemia , Índice de Massa Corporal , Estado Nutricional , População Rural , Migrantes , Humanos , China/epidemiologia , Feminino , Masculino , População Rural/estatística & dados numéricos , Migrantes/estatística & dados numéricos , Pré-Escolar , Criança , Anemia/epidemiologia , Prevalência , Dieta/efeitos adversos , Pais , Magreza/epidemiologia , Transtornos do Crescimento/epidemiologia , Comportamento Alimentar , Estudos Transversais , Inquéritos e Questionários
2.
J Sci Food Agric ; 104(5): 3147-3155, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38072645

RESUMO

BACKGROUND: Carotenoids play key roles in photosynthesis and are widely used in foods as natural pigments, antioxidants, and health-promoting compounds. Enhancing carotenoid production in microalgae via biotechnology has become an important area of research. RESULTS: We knocked out the Na+ /Ca2+ antiporter gene slr0681 in Synechocystis sp. PCC 6803 via homologous recombination and evaluated the effects on carotenoid production under normal (NL) and high-light (HL) conditions. On day 7 of NL treatment in calcium ion (Ca2+ )-free medium, the cell density of Δslr0681 decreased by 29% compared to the wild type (WT). After 8 days of HL treatment, the total carotenoid contents decreased by 35% in Δslr0681, and the contents of individual carotenoids were altered: myxoxanthophyll, echinenone, and ß-carotene contents increased by 10%, 50%, and 40%, respectively, while zeaxanthin contents decreased by ~40% in Δslr0681 versus the WT. The expression patterns of carotenoid metabolic pathway genes also differed: ipi expression increased by 1.2- to 8.5-fold, whereas crtO and crtR expression decreased by ~90% and 60%, respectively, in ∆slr0681 versus the WT. In addition, in ∆slr0681, the expression level of psaB (encoding a photosystem I structural protein) doubled, whereas the expression levels of the photosystem II genes psbA2 and psbD decreased by ~53% and 84%, respectively, compared to the WT. CONCLUSION: These findings suggest that slr0681 plays important roles in regulating carotenoid biosynthesis and structuring of the photosystems in Synechocystis sp. This study provides a theoretical basis for the genetic engineering of microalgae photosystems to increase their economic benefits and lays the foundation for developing microalgae germplasm resources with high carotenoid contents. © 2023 Society of Chemical Industry.


Assuntos
Synechocystis , Synechocystis/genética , Synechocystis/metabolismo , Proteínas de Bactérias/metabolismo , Carotenoides/metabolismo , beta Caroteno/metabolismo , Zeaxantinas/metabolismo
3.
J Clin Hypertens (Greenwich) ; 25(8): 784-793, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37433158

RESUMO

This study was aimed at assessing the risk factors for hypertension (HTN) and prehypertension (PHT) in order to clarify the role of lipid accumulation product (LAP) in the development of HTN among nondiabetic individuals. A large cross-sectional study was conducted in community health service centers in urban Bengbu, Anhui Province, China. All participants completed an interview questionnaire and procedures to obtain physical measurements and biochemical indicators. Multivariate logistic regression was used to test for the prevalence of HTN and PHT in relation to each quartile increase in LAP level and family history of HTN. The resulting interaction effects were evaluated by relative excess risk of interaction (RERI), attributable proportion due to interaction (AP), and synergy index (SI). A total of 7733 subjects were enrolled in the study. The overall prevalence rates of PHT and HTN were 37.1% and 24.8%, respectively. After adjusting for confounding factors, multinomial logistic regression analysis showed that compared with subjects in LAP quartile 1, those in quartile 3 (OR, 1.257; 95% CI, 1.062-1.494) and quartile 4 (OR, 1.323; 95% CI, 1.101-1.592) had a significantly higher risk for HTN (p for trend < .001). A significant interaction was observed between LAP and family history of HTN in men (AP, 0.1661; 95% CI, 0.0024-0.3296; SI, 1.4037; 95% CI, 1.0599-1.8593) and in women (RERI, 1.4111; 95% CI, 0.1458-2.9678; AP, 0.1662; 95% CI, 0.0085-0.3237; SI, 1.3886; 95% CI, 1.0568-1.8247). The results demonstrated that the interactive effects of LAP with family history of HTN may influence the development of HTN synergistically.


Assuntos
Hipertensão , Produto da Acumulação Lipídica , Pré-Hipertensão , Masculino , Humanos , Feminino , Hipertensão/epidemiologia , Estudos Transversais , Obesidade/epidemiologia , Índice de Massa Corporal , Fatores de Risco , China/epidemiologia
4.
BMC Cardiovasc Disord ; 23(1): 336, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37393221

RESUMO

BACKGROUND: The triglyceride glucose (TyG) index has been regarded as an effective proxy of Insulin resistance (IR). Studies on the TyG index, obesity and the risk of prehypertension (PHT) in elderly people are not apparent currently. The study sought to investigate the predictive value of TyG index and the associations with PHT risk and obesity. METHODS: A community-based cross-sectional study was conducted in Bengbu City, Anhui province, China. Participants older than 65 years accepted questionnaire surveys, physical examinations and blood biochemistry tests. Based on the testing results, indicators including BMI (body mass index), WC (waist circumference), WHtR (waist-to-height-ratio), LAP(Lipid accumulation products) and TyG were calculated. Residents were classified into quartiles by their TyG indexes. Receiver operating characteristic curve (ROC) analysis was carried out to predict obesity indices for PHT. The three additive interaction indicators, RERI (relative excess risk due to interaction), AP (attributable proportion due to interaction) and S (synergy index) were used to assess the interaction impacts. RESULTS: Two thousand six hundred sixty-six eligible elderly people were included in study and the prevalence of PHT was 71.04% (n = 1894). With increasing TyG index quartile, PHT became more prevalent. After adjusting for confounding factors, the prevalence of PHT risk with TyG levels in the fourth quartile (Q4, male: 2.83, 95%CI: 1.77-4.54; female: 2.75, 95%CI:1.91-3.97) was greater than that in the first quartile (Q1:ref). TyG index (AUC: 0.626, 95%CI: 0.602 to 0.650) was superior than BMI (AUC: 0.609, 95%CI: 0.584 to 0.633) in predicting PHT among females. Eventually, there were significant interactions of TyG index with obesity in males (General obesity: AP = 0.87, 95%CI: 0.72 to 1.02, S = 10.48, 95%CI: 3.43 to 31.97; Abdominal obesity: AP = 0.60,95%CI: 0.38 to 0.83, S = 3.53, 95%CI: 1.99 to 6.26) and females (General obesity: AP = 0.89, 95%CI: 0.79 to 0.98, S = 12.46, 95%CI: 5.61 to 27.69; Abdominal obesity: AP = 0.66, 95%CI: 0.51 to 0.82, S = 3.89, 95%CI:2.54 to 5.98). CONCLUSION: TyG index and PHT risk are tightly correlated. The risk of chronic disease in the elderly can be decreased by early detection of PHT utilizing the TyG index. In this research, the TyG index was more predictable than other indicators of obesity.


Assuntos
Obesidade Abdominal , Pré-Hipertensão , Idoso , Humanos , Feminino , Masculino , Estudos Transversais , Obesidade/diagnóstico , Obesidade/epidemiologia , China/epidemiologia , Glucose
5.
J Environ Manage ; 344: 118498, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37384983

RESUMO

Coal gasification is an effective way to use coal cleanly and efficiently, and coal gasification fine slag is a by-product of coal gasification with high carbon content, large specific surface area, developed pore structure and large output during production. At present, combustion has become an effective way to dispose of coal gasification fine slag on a large scale, and the coal gasification fine slag after combustion treatment can be further used for construction raw materials. In this paper, the emission characteristics of gas-phase pollutants and particulate matter under different combustion temperatures (900 °C, 1100 °C, 1300 °C) and combustion atmosphere (5%, 10%, 21% O2 concentration) are studied with the drop tube furnace experimental system. By co-firing different proportions of coal gasification fine slag (10%, 20%, 30%) and raw coal, the pollutants formation law under co-firing conditions is studied. Scanning electron microscopy-energy spectroscopy (SEM-EDS) is used to characterize the apparent morphology and elemental composition of particulate samples. The measurement results of gas-phase pollutants show that the increase of furnace temperature and O2 concentration can effectively promote combustion and improve burnout characteristics, but the emission of gas-phase pollutants increases. A certain proportion (10%-30%) of coal gasification fine slag is added to the raw coal, which reduces the total emission of gas-phase pollutants (NOx and SOx). Studies on the characteristics of particulate matter formation show that co-firing with coal gasification fine slag in raw coal can effectively reduce submicron particle emission, and the lower fine particle emission is also detected at lower furnace temperature and oxygen concentration. The element analysis of particulate matter formation shows that the Fe, Si and S elements content of submicron particle generated by YL (the coal gasification fine slag generated by water slurry furnace in of Shaanxi Extended China Coal Yulin Energy Chemical Co., Ltd) sample increases significantly with the increase of furnace temperature and O2 concentration, which is the main influencing factor for the increase of submicron particle. With the increase of the mixing ratio of YL sample, the content of major elements such as Fe, K and Mg of submicron particle decreases significantly, which is an important reason why the amount of the submicron particle decreases.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Carvão Mineral/análise , Temperatura , Material Particulado/análise , Poluentes Atmosféricos/análise , Poluentes Ambientais/análise
6.
Plant Dis ; 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36825309

RESUMO

Auricularia heimuer is a gelatinous fungus with great edible and medicinal values. In September 2021, a suspected cobweb disease was found in some A. heimuer farms in Fujian Province, China. The disease caused white cottony mycelium to grow on the basal surface of the A. heimuer at the beginning of infection and gradually spread along the outer edge of the fruiting body, and eventually the white pathogen mycelium covered the entire fruiting body, which eventually led to the wilting and death of about 35% of A. heimuer . Two heavily infected tissues of A. heimuer were collected and two isolates were obtained by single spore isolation and purification technique. The pathogen colonies grew 10 to 12 mm per day on potato dextrose agar (PDA), and the colonies were initially white in color and gradually changed to yellowish brown with neat margins. Well-developed mycelium with septum, Conidiophores are bottle-stemmed and whorl-shaped branches, Conidia solitary, as ovoid, colorless singletons or doublets. The chlamydospores are yellowish, smooth surface, with 2-3 septa, size 9-22 µm × 30-38 µm. These morphological features are consistent with the Hypomyces mycophilus (Gea et al. 2019; Wang et al. 2021). For molecular identification, genomic DNA of the two isolates was obtained using an extraction kit (Biocolor, Shanghai, China), internal transcribed spacers (ITS) regions and 5SrRNA were amplified using ITS1 and ITS4 primers (White et al. 1990). A 590 bp DNA fragment was obtained and the sequences were deposited in GenBank (Accession Nos. OP715875 and OP782039), A BLAST search in GenBank revealed the highest similarity (≥99%) to H. mycophilus (GenBank Accession Nos. MH857567 and KU937111) . To fulfill Koch's postulates, the isolates cultured on PDA plates for 10 days were made into a spore suspension with sterile water at a concentration of 5 × 106 conidia/ml and sprayed onto twenty healthy fruiting bodies grown to about 2 cm in diameter, and another ten healthy fruiting bodies sprayed with sterile water as control, and incubated in an artificial climate chamber at 25℃ and relative humidity of 90%-95% (Back et al. 2012). After 4 days of inoculation, the pathogen started to germinate and slowly grew white mycelium, then the white mycelium multiplied at the base of the fruiting bodies and spread from the base to the periphery, and finally the fruiting bodies were completely covered by the pathogenic mycelium and gradually wilted. The symptoms were consistent with the natural disease symptoms under cultivation conditions, while the control group had normal growth of the seeds and no disease symptoms. H. mycophilus was reisolated and purified from symptomatic cotyledons and identified by the above method, and the results of the two experiments were consistent. To our knowledge, this is the first report of H. mycophilus causing cobweb disease in A. heimuer.

7.
Life Sci Alliance ; 6(1)2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36410795

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is prevalent worldwide; about 25% of NAFLD silently progress into steatohepatitis, in which some of them may develop into fibrosis, cirrhosis and liver failure. However, few drugs are available for NAFLD, partly because of an incomplete understanding of its pathogenic mechanisms. Here, using in vivo and in vitro gain- and loss-of-function approaches, we identified up-regulated DKK1 plays a pivotal role in high-fat diet-induced NAFLD and its progression. Mechanistic analysis reveals that DKK1 enhances the capacity of hepatocytes to uptake fatty acids through the ERK-PPARγ-CD36 axis. Moreover, DKK1 increased insulin resistance by activating the JNK signaling, which in turn exacerbates disorders of hepatic lipid metabolism. Our finding suggests that DKK1 may be a potential therapeutic and diagnosis candidate for NAFLD and metabolic disorder progression.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Dieta Hiperlipídica , Hepatócitos , Peptídeos e Proteínas de Sinalização Intercelular , Metabolismo dos Lipídeos/genética , Cirrose Hepática , Hepatopatia Gordurosa não Alcoólica/genética , Antígenos CD36/metabolismo
8.
Arch Public Health ; 80(1): 217, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36183132

RESUMO

BACKGROUND: Lipid accumulation product (LAP) is considered to be a new convenient useful indicator to assess the visceral fat. Therefore, we aimed to evaluate the risk factors of impaired fasting glucose (IFG) and diabetes, and explore the possible interacting influences of LAP with other factors on the risk of IFG and diabetes among Chinese normotension adults. METHODS: A multistage stratified cluster sampling method was conducted to select urban residents in Bengbu, China. For each eligible participant, data on questionnaire survey, anthropometric measurements and laboratory tests were obtained. The effects of body mass index (BMI), waist circumference (WC), waist to height ratio (WHtR) and LAP for predicting IFG and diabetes were performed by multiple logistic regressions and receiver operating characteristic (ROC) analyses. The interaction effects were evaluated by relative excess risk of interaction (RERI), attributable proportion due to interaction (AP) and synergy index (SI). RESULTS: Six thousand, four hundred sixty-seven normotension subjects (2695 men and 3772 women) were enrolled in our study, the prevalence of IFG and diabetes were 9.37% and 14.33%, respectively. When assessed using ROC curve analysis, LAP exhibited higher diagnostic accuracy for identifying IFG and diabetes than BMI, the area under the AUC curve was 0.650 (95% CI: 0.637 to 0.662). After adjustment for age, sex, educational level and other confounding factors, multivariate logistic regression analyses indicated that subjects with the fourth quartile of LAP were more likely to develop IFG (adjusted OR: 2.735, 95% CI: 1.794-4.170) and diabetes (adjusted OR: 1.815, 95% CI: 1.297-2.541) than those with the first quartile. A significant interaction between LAP and family history of diabetes was observed in participants (RERI = 1.538, 95%CI: 0.167 to 3.612; AP = 0.375, 95%CI: 0.118 to 0.631; SI = 1.980, 95%CI: 1.206 to 3.251). However, a significant interaction between LAP and abdominal obesity was indicated by the value of RERI (1.492, 95%CI: 0.087 to 3.723) and AP (0.413, 95%CI: 0.014 to 0.756), but not the value of SI (1.824, 95%CI: 0.873 to 3.526). CONCLUSION: Our results demonstrated that there might be synergistic effect between LAP and family history of diabetes on the risk of IFG and diabetes.

9.
Cells ; 11(15)2022 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-35954231

RESUMO

Multiple endocrine neoplasia type 1 (MEN1) is an inherited disease caused by mutations in the MEN1 gene encoding a nuclear protein menin. Among those different endocrine tumors of MEN1, the pancreatic neuroendocrine tumors (PNETs) are life-threatening and frequently implicated. Since there are uncertainties in genotype and phenotype relationship and there are species differences between humans and mice, it is worth it to replenish the mice model with human cell resources. Here, we tested whether the patient-origin induced pluripotent stem cell (iPSC) lines could phenocopy some defects of MEN1. In vitro ß-cell differentiation revealed that the percentage of insulin-positive cells and insulin secretion were increased by at least two-fold in MEN1-iPSC derived cells, which was mainly resulted from significantly higher proliferative activities in the pancreatic progenitor stage (Day 7-13). This scenario was paralleled with increased expressions of prohormone convertase1/3 (PC1/3), glucagon-like peptide-1 (GLP-1), GLP-1R, and factors in the phosphatidylinositol 3-kinase (PI3K)/AKT signal pathway, and the GLP-1R was mainly expressed in ß-like cells. Blockages of either GLP-1R or PI3K significantly reduced the percentages of insulin-positive cells and hypersecretion of insulin in MEN1-derived cells. Furthermore, in transplantation of different stages of MEN1-derived cells into immune-deficient mice, only those ß-like cells produced tumors that mimicked the features of the PNETs from the original patient. To the best of our knowledge, this was the first case using patient-origin iPSCs modeling most phenotypes of MEN1, and the results suggested that GLP-1R may be a potential therapeutic target for MEN1-related hyperinsulinemia.


Assuntos
Células-Tronco Pluripotentes Induzidas , Neoplasia Endócrina Múltipla Tipo 1 , Tumores Neuroectodérmicos Primitivos , Animais , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Insulina/metabolismo , Insulina Regular Humana , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas
10.
Asia Pac J Clin Nutr ; 31(2): 305-311, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35766566

RESUMO

BACKGROUND AND OBJECTIVES: This study evaluated the relationship between dietary inflammatory index (DII) and metabolic health in the Chinese elderly. METHODS AND STUDY DESIGN: A total of 6,730 participants from the "Community-based Cardiovascular and Health Promotion Study" (CoCHPS) cohort were included in this study. The DII scores were acquired using a validated 125-item food-frequency questionnaire (FFQ) (ranged -5.84 to 3.90). The correlation of DII with metabolic health indexes was evaluated with logistic regression and multivariable cox regression using SPSS and R software. RESULTS: Compared with low DII scores, subjects in the highest DII score quartiles had higher odds of metabolic dysfunction (OR=1.36, 95% CI: 1.07-1.68, p trend=0.023). In the subgroup analyses, the effect of a pro-inflammatory diet on metabolic dysfunction was particularly evident among people with hyperglycaemia (HR=1.58, 95% CI: 1.35-2.14), hypertension (HR=1.48, 95% CI: 1.07-2.09), dyslipidemia (HR=1.45, 95% CI: 1.24-1.87), abdominal obesity (HR=2.16, 95% CI: 1.57-2.96), and ≥60 years old (HR=1.32, 95% CI: 1.04-1.56) or who were women (HR=1.35, 95% CI: 1.08-1.67). CONCLUSIONS: DII score was associated with metabolic health. Further studies are needed to deepen our understanding of dietary parameters and different populations.


Assuntos
Dieta , Inflamação , Idoso , China/epidemiologia , Estudos de Coortes , Feminino , Humanos , Inflamação/complicações , Inflamação/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco
11.
Stem Cell Res Ther ; 13(1): 159, 2022 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-35410439

RESUMO

BACKGROUND: Various methods have been developed to generate hepatic cells from human pluripotent stem cells (hPSCs) that rely on the combined use of multiple expensive growth factors, limiting industrial-scale production and widespread applications. Small molecules offer an attractive alternative to growth factors for producing hepatic cells since they are more economical and relatively stable. METHODS: We dissect small-molecule combinations and identify the ideal cocktails to achieve an optimally efficient and cost-effective strategy for hepatic cells differentiation, expansion, and maturation. RESULTS: We demonstrated that small-molecule cocktail CIP (including CHIR99021, IDE1, and PD0332991) efficiently induced definitive endoderm (DE) formation via increased endogenous TGF-ß/Nodal signaling. Furthermore, we identified that combining Vitamin C, Dihexa, and Forskolin (VDF) could substitute growth factors to induce hepatic specification. The obtained hepatoblasts (HBs) could subsequently expand and mature into functional hepatocyte-like cells (HLCs) by the established chemical formulas. Thus, we established a stepwise strategy with complete small molecules for efficiently producing scalable HBs and functionally matured HLCs. The small-molecule-derived HLCs displayed typical functional characteristics as mature hepatocytes in vitro and repopulating injured liver in vivo. CONCLUSION: Our current small-molecule-based hepatic generation protocol presents an efficient and cost-effective platform for the large-scale production of functional human hepatic cells for cell-based therapy and drug discovery using.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Diferenciação Celular , Terapia Baseada em Transplante de Células e Tecidos , Hepatócitos/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Fígado , Células-Tronco Pluripotentes/metabolismo
12.
Nano Lett ; 22(7): 2755-2761, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35315673

RESUMO

Oxide heterointerfaces with high carrier density can interact strongly with the lattice phonons, generating considerable plasmon-phonon coupling and thereby perturbing the fascinating optical and electronic properties, such as two-dimensional electron gas, ferromagnetism, and superconductivity. Here we use infrared-spectroscopic nanoimaging based on scattering-type scanning near-field optical microscopy (s-SNOM) to quantify the interaction of electron-phonon coupling and the spatial distribution of local charge carriers at the SrTiO3/TiO2 interface. We found an increased high-frequency dielectric constant (ε∞ = 7.1-9.0) and charge carrier density (n = 6.5 × 1019 to 1.5 × 1020 cm-3) near the heterointerface. Moreover, quantitative information between the charge carrier density and extension thickness across the heterointerface has been extracted by monochromatic near-field imaging. A direct evaluation of the relationship between the thickness and the interaction of charge carrier-phonon coupling of the heterointerface would provide valuable information for the development of oxide-based electronic devices.

13.
Adv Sci (Weinh) ; 9(6): e2104141, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34997681

RESUMO

Oxide semiconductors are key materials in many technologies from flat-panel displays,solar cells to transparent electronics. However, many potential applications are hindered by the lack of high mobility p-type oxide semiconductors due to the localized O-2p derived valence band (VB) structure. In this work, the VB structure modulation is reported for perovskite Ba2 BiMO6 (M = Bi, Nb, Ta) via the Bi 6s2 lone pair state to achieve p-type oxide semiconductors with high hole mobility up to 21 cm2 V-1 s-1 , and optical bandgaps widely varying from 1.5 to 3.2 eV. Pulsed laser deposition is used to grow high quality epitaxial thin films. Synergistic combination of hard x-ray photoemission, x-ray absorption spectroscopies, and density functional theory calculations are used to gain insight into the electronic structure of Ba2 BiMO6 . The high mobility is attributed to the highly dispersive VB edges contributed from the strong coupling of Bi 6s with O 2p at the top of VB that lead to low hole effective masses (0.4-0.7 me ). Large variation in bandgaps results from the change in the energy positions of unoccupied Bi 6s orbital or Nb/Ta d orbitals that form the bottom of conduction band. P-N junction diode constructed with p-type Ba2 BiTaO6 and n-type Nb doped SrTiO3 exhibits high rectifying ratio of 1.3 × 104 at ±3 V, showing great potential in fabricating high-quality devices. This work provides deep insight into the electronic structure of Bi3+ based perovskites and guides the development of new p-type oxide semiconductors.

14.
JCI Insight ; 6(19)2021 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-34622799

RESUMO

A population genetic study identified that the asialoglycoprotein receptor 1 (ASGR1) mutation carriers had substantially lower non-HDL-cholesterol (non-HDL-c) levels and reduced risks of cardiovascular diseases. However, the mechanism behind this phenomenon remained unclear. Here, we established Asgr1-knockout mice that represented a plasma lipid profile with significantly lower non-HDL-c and triglyceride (TG) caused by decreased secretion and increased uptake of VLDL/LDL. These 2 phenotypes were linked with the decreased expression of microsomal triglyceride transfer protein and proprotein convertase subtilisin/kexin type 9, 2 key targeted genes of sterol regulatory element-binding proteins (SREBPs). Furthermore, there were fewer nuclear SREBPs (nSREBPs) on account of more SREBPs being trapped in endoplasmic reticulum, which was caused by an increased expression of insulin-induced gene 1 (INSIG1), an anchor of SREBPs. Overexpression and gene knockdown interventions, in different models, were conducted to rescue the ASGR1-deficient phenotypes, and we found that INSIG1 knockdown independently reversed the ASGR1-mutated phenotypes with increased serum total cholesterol, LDL-c, TG, and liver cholesterol content accompanied by restored SREBP signaling. ASGR1 rescue experiments reduced INSIG1 and restored the SREBP network defect as manifested by improved apolipoprotein B secretion and reduced LDL uptake. Our observation demonstrated that increased INSIG1 is a critical factor responsible for ASGR1 deficiency-associated lipid profile changes and nSREBP suppression. This finding of an ASGR1/INSIG1/SREBP axis regulating lipid hemostasis may provide multiple potential targets for lipid-lowering drug development.


Assuntos
Receptor de Asialoglicoproteína/genética , Metabolismo dos Lipídeos/genética , Proteínas de Membrana/metabolismo , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo , Animais , Proteínas de Transporte/metabolismo , Núcleo Celular/metabolismo , HDL-Colesterol/metabolismo , LDL-Colesterol/metabolismo , VLDL-Colesterol/metabolismo , Retículo Endoplasmático/metabolismo , Homeostase , Camundongos , Camundongos Knockout , Pró-Proteína Convertase 9/metabolismo , Transdução de Sinais , Triglicerídeos/metabolismo
15.
Adv Mater ; 33(50): e2006230, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33797084

RESUMO

Wide bandgap oxide semiconductors constitute a unique class of materials that combine properties of electrical conductivity and optical transparency. They are being widely used as key materials in optoelectronic device applications, including flat-panel displays, solar cells, OLED, and emerging flexible and transparent electronics. In this article, an up-to-date review on both the fundamental understanding of materials physics of oxide semiconductors, and recent research progress on design of new materials and high-performing thin film transistor (TFT) devices in the context of fundamental understanding is presented. In particular, an in depth overview is first provided on current understanding of the electronic structures, defect and doping chemistry, optical and transport properties of oxide semiconductors, which provide essential guiding principles for new material design and device optimization. With these principles, recent advances in design of p-type oxide semiconductors, new approaches for achieving cost-effective transparent (flexible) electrodes, and the creation of high mobility 2D electron gas (2DEG) at oxide surfaces and interfaces with a wealth of fascinating physical properties of great potential for novel device design are then reviewed. Finally, recent progress and perspective of oxide TFT based on new oxide semiconductors, 2DEG, and low-temperature solution processed oxide semiconductor for flexible electronics will be reviewed.

16.
J Environ Manage ; 290: 112690, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33901829

RESUMO

Pressurized oxy-combustion is an emerging and more efficient technology for carbon capture, utilization, and storage than the first generation (atmospheric) oxy-combustion. NOx is a major conventional pollutant produced in pressurized oxy-combustion. In pressurized oxy-combustion, the utilization of latent heat from moisture and removal of acid gases (NOx and SOx) are mainly conducted in an integrated direct-contact wash column. Recent studies have shown that NOx particular inlet concentration should be maintained before direct contact wash column to remove NOx and SOx efficiently. As a result, minimizing NOx for environmental reasons, avoiding corrosion in carbon capture, utilization, and storage, and achieving effective NOx and SOx removal in direct contact wash columns are crucial. Reburning is a capable and affordable technology for NOx reduction; however, this process is still less studied at elevated pressure, particularly in pressurized oxy-combustion. In this paper, the kinetic evaluation and optimization study on NOx reduction by reburning under pressurized oxy-combustion was conducted. First, the most suitable mechanism was selected by comparing the results of different kinetic models with the experimental data in literature at atmospheric and elevated pressures. Based on the validated mechanism, a variety of parameters were studied at high pressure, i.e., comparing the effects of oxy and the air environment, different reburning fuels, residence time, H2O concentration, CH4/NO ratio, and equivalence ratio on the NO reduction. The results show that de-NOx efficiency in an oxy environment is significantly enhanced compared to the air environment. Improvement in the de-NOx efficiency is considerably higher with a pressure increase of up to 10 atm, but the effect is less prominent above 10 atm. The formation of HCN is significantly reduced while the N2 formation is enhanced as the pressure increases from 1 to 10 atm. The residence time required for the maximum NO reduction decreases as the pressure increases from 1 atm to 15 atm. At the higher pressure, the NO reduction rises prominently when the ratio of CH4/NO increases from 1 to 2; however, the effect fades after that. At higher pressure, the NO reduction by CH4 reburning decreases as the H2O concentration increases from 0 to 35%. The optimum equivalence ratio and high pressure for maximum NO reduction are 1.5 and 10 atm, respectively. This study could provide guidance for designing and optimizing a pressurized reburning process for NOx reduction in POC systems.


Assuntos
Poluentes Atmosféricos , Gases , Poluentes Atmosféricos/análise , Temperatura Alta , Cinética
17.
J Steroid Biochem Mol Biol ; 211: 105881, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33766737

RESUMO

Human hepatocyte-like cells (HLCs) derived from human pluripotent stem cells (hPSCs) represent a promising cell source for the assessment of hepatotoxicity and pharmaceutical safety testing. However, the hepatic functionality of HLCs remains significantly inferior to primary human hepatocytes. The bioactive vitamin D (VD), calcitriol, promotes the differentiation of many types of cells, and its deficiency is correlated to the severity of liver diseases. Whether calcitriol contributes to the differentiation of HLCs needs to be explored. Here, we found that the supplementation of calcitriol improved the functionalities of hPSCs-derived HLCs in P450 activities, urea production, and albumin secretion. Moreover, calcitriol also enhanced mitochondrial respiratory function with increased protein expression levels of the subunit of respiratory enzyme complexes in HLCs. Further analyses showed that the mitochondrial biogenesis regulators and mitophagy were increased by calcitriol, thus improving the mitochondrial quality. These improvements in functionality and mitochondrial condition were dependent on vitamin D receptor (VDR) because the improvements were abolished under VDR-deficient conditions. Our finding provides a cost-effective chemical process for HLC maturation to meet the demand for basic research and potential clinic applications.


Assuntos
Calcitriol/farmacologia , Diferenciação Celular , Hepatócitos/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Mitocôndrias/efeitos dos fármacos , Mitofagia , Biogênese de Organelas , Células Cultivadas , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Mitocôndrias/metabolismo , Vitaminas/farmacologia
18.
Small ; 17(12): e2006930, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33656259

RESUMO

Aliovalent doping is widely adopted to tune the electronic structure of transition-metal oxides for design of low-cost, active electrocatalysts. Here, using single-crystalline thin films as model electrocatalysts, the structure-activity relationship of Fe states doping in perovskite LaNiO3 for oxygen evolution reaction (OER) is studied. Fe4+ state is found to be crucial for enhancing the OER activity of LaNiO3 , dramatically increasing the activity by six times, while Fe3+ has negligible effect. Spectroscopic studies and DFT calculations indicate Fe4+ states enhance the degree of Ni/Fe 3d and O 2p hybridization, and meanwhile produce down-shift of the unoccupied density of states towards lower energies. Such electronic features reduce the energy barrier for interfacial electron transfer for water oxidization by 0.2 eV. Further theoretical calculations and H/D isotope experiments reveal the electronic states associated with Fe4+ -O2- -Ni3+ configuration accelerate the deprotonation of *OH to *O (rate-determining step), and thus facilitate fast OER kinetics.

19.
Stem Cell Res Ther ; 12(1): 151, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33632328

RESUMO

BACKGROUND: Chemically strategies to generate hepatic cells from human pluripotent stem cells (hPSCs) for the potential clinical application have been improved. However, producing high quality and large quantities of hepatic cells remain challenging, especially in terms of step-wise efficacy and cost-effective production requires more improvements. METHODS: Here, we systematically evaluated chemical compounds for hepatoblast (HB) expansion and maturation to establish a robust, cost-effective, and reproducible methodology for self-renewal HBs and functional hepatocyte-like cell (HLC) production. RESULTS: The established chemical cocktail could enable HBs to proliferate nearly 3000 folds within 3 weeks with preserved bipotency. Moreover, those expanded HBs could be further efficiently differentiated into homogenous HLCs which displayed typical morphologic features and functionality as mature hepatocytes including hepatocyte identity marker expression and key functional activities such as cytochrome P450 metabolism activities and urea secretion. Importantly, the transplanted HBs in the injured liver of immune-defect mice differentiated as hepatocytes, engraft, and repopulate in the injured loci of the recipient liver. CONCLUSION: Together, this chemical compound-based HLC generation method presents an efficient and cost-effective platform for the large-scale production of functional human hepatic cells for cell-based therapy and drug discovery application.


Assuntos
Hepatócitos , Células-Tronco Pluripotentes , Animais , Diferenciação Celular , Terapia Baseada em Transplante de Células e Tecidos , Humanos , Fígado , Camundongos
20.
Stem Cell Res ; 51: 102161, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33461039

RESUMO

Dickkopf1 (DKK1) is a secreted inhibitor for the Wnt signalling, which is involved in cell proliferation, tissue regeneration and embryonic development. Using CRISPR/Cas9 editing, we established a homozygous mutant DKK1 human embryonic stem cell line (WAe001-A-21). It has a 41 bp deletion in exon 2 of DKK1, leading to its coding frame shift. The WAe001-A-21 cell line maintains a normal karyotype, pluripotency markers, typical stem cell morphology and the ability to differentiate into three germ layers.


Assuntos
Células-Tronco Embrionárias Humanas , Sistemas CRISPR-Cas/genética , Linhagem Celular , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Células-Tronco Embrionárias , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética
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