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1.
Artigo em Inglês | MEDLINE | ID: mdl-31955464

RESUMO

BACKGROUND: Minimal erythema dose (MED) has substantial inter- and intraindividual variations, reflecting the influence of very diverse factors. However, related studies showed little consistency probably because of their limited sample size. OBJECTIVE: To identify the factors associated with minimal erythema dose variations in a large-scale population study. METHODS: The MED test was performed by following the international standard procedure on 22,146 subjects. The results were analyzed in adjusted multivariable linear and logistic regression models. RESULTS: This large-scale study revealed that lower MED was consistently associated with lighter skin [ß-coefficient = -0.33, 95% confidence interval (CI) -0.36--0.30, P = 6.41 × 10-84 ]. Females had significantly higher MED than male (ß = 0.91, 0.32-1.50, P = 2.93 × 10-3 ). Stratified analyses showed that MED was not associated with age [female: odds ratio (OR) = 0.99, 0.98-1.01; male: OR = 0.99, 0.97-1.00]. MED was lower in summer than in other seasons (spring: OR = 1.08, 1.06-1.11; autumn: OR = 1.11, 1.08-1.13; winter: OR = 1.20, 1.18-1.22). Furthermore, MED was associated with air temperature (ß = -0.36, -0.49--0.23, P = 4.81 × 10-8 ) and air pressure (ß = -0.64, -0.82--0.46, P = 8.01 × 10-12 ) in summer only while not in other seasons. CONCLUSIONS: This study provides unprecedented evidence that MED is associated with skin color, sex, season and meteorological factors, but not with age.

2.
FASEB J ; 34(1): 525-539, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914679

RESUMO

Whereas much is known about the genes regulated by ΔNp63α in keratinocytes, how ΔNp63α is regulated is less clear. During studies with the hydroxylase, factor inhibiting hypoxia-inducible factor 1 (FIH-1), we observed increases in epidermal ΔNp63α expression along with proliferative capacity in a conditional FIH-1 transgenic mouse. Conversely, loss of FIH-1 in vivo and in vitro attenuated ΔNp63α expression. To elucidate the FIH-1/p63 relationship, BioID proteomics assays identified FIH-1 binding partners that had the potential to regulate p63 expression. FIH-1 interacts with two previously unknown partners, Plectin1 and signal transducer and activator of transcription 1 (STAT1) leading to the regulation of ΔNp63α expression. Two known interactors of FIH-1, apoptosis-stimulating of P53 protein 2 (ASPP2) and histone deacetylase 1 (HDAC1), were also identified. Knockdown of ASPP2 upregulated ΔNp63α and reversed the decrease in ΔNp63α by FIH-1 depletion. Additionally, FIH-1 regulates growth arrest and DNA damage-45 alpha (GADD45α), a negative regulator of ΔNp63α by interacting with HDAC1. GADD45α knockdown rescued reduction in ΔNp63α by FIH-1 depletion. Collectively, our data reveal that FIH-1 positively regulates ΔNp63α in keratinocytes via variety of signaling partners: (a) Plectin1/STAT1, (b) ASPP2, and (c) HDAC1/GADD45α signaling pathways.

3.
Reprod Biomed Online ; 40(2): 287-295, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31956063

RESUMO

Vascular endothelial growth factor (VEGF) plays important roles in the pathogenesis of polycystic ovary syndrome (PCOS). Several single nucleotide polymorphisms (SNP) of the VEGF gene have been identified and are associated with the aberrant secretion of VEGF protein. This meta-analysis aimed to evaluate the impact of the VEGF +405G>C (rs2010963), -460C>T (rs833061) and -2578A>C (rs699947) polymorphisms on PCOS susceptibility. A systematic search of the Embase, PubMed, Web of Science and Wanfang databases was carried out to identify relevant studies published before 19 July 2019. Seven eligible studies were included in this meta-analysis involving 1100 patients with PCOS and 1141 control individuals. The pooled analysis revealed no significant association between PCOS risk and the +405G>C (rs2010963), -460C>T (rs833061) or -2578A>C (rs699947) polymorphisms in women. Subgroup analysis by ethnicity indicated that Asian women carrying the VEGF +405C allele had a lower risk of PCOS (C versus G: odds ratio [OR] 0.731, 95% confidence interval [CI] 0.544-0.982, P < 0.05, I2 = 46.4%; CG versus GG: OR 0.667, 95% CI 0.469-0.948, P < 0.05, I2 = 18.4%; CC versus GG: OR 0.611, 95% CI 0.390-0.958, P < 0.05, I2 = 24.3%). The study demonstrates that for all women regardless of ethnicity, no significant associations between VEGF SNP and PCOS were observed; however, +405G>C (rs2010963) may protect Asian women from PCOS.

4.
Appl Microbiol Biotechnol ; 104(5): 1883-1890, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31932892

RESUMO

C-Glycosides, a special type of glycoside, are frequently distributed in many kinds of medicinal plants, such as puerarin and mangiferin, showing various and significant bioactivities. C-Glycosides are usually characterized by the C-C bond that forms between the anomeric carbon of sugar moieties and the carbon atom of aglycon, which is usually resistant against acidic hydrolysis and enzymatic treatments. Interestingly, C-glycosides could be cleaved by several intestinal bacteria, but whether the enzymatic cleavage of C-C glycosidic bond is reduction or hydrolysis has been controversial; furthermore, whether existence of a "C-glycosidase" directly catalyzing the cleavage is not clear. Here we review research advances about the discovery and mechanism of intestinal bacteria in enzymatic cleavage of C-C glycosidic bond with an emphasis on the identification of enzymes manipulation the deglycosylation. Finally, we give a brief conclusion about the mechanism of C-glycoside deglycosylation and perspectives for future study in this field.

5.
Sci Total Environ ; 705: 135829, 2020 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31972954

RESUMO

The exploitation of groundwater resources is of great importance and has become crucial in the last few decades, especially in arid regions, where surface water resources are scarce and unreliable. The Hexi Corridor (HC) is one of the most agriculturally rich and densely populated areas of arid northwestern China. Increasing demand for water, due to rapid population growth, oasis expansion and urbanization, has increased groundwater use, resulting in wide-scale depletion in this region. Sustainable management of aquifers in the HC requires accurate estimates of the current situation of groundwater resource sustainability. In this work, groundwater storage anomaly (∆GWS) were estimated using the Gravity Recovery and Climate Experiment (GRACE) satellite data, the Global Land Data Assimilation System (GLDAS) data and the water-table fluctuation (WTF) method based on in-situ groundwater level data. Combined with the groundwater sustainability index (SIGWS), groundwater sustainability in the HC was then evaluated. Potential factors that could affect regional groundwater sustainability were analyzed by including and testing climate and socio-economic variables during the period of 1981 to 2016. We found that (1) groundwater in the HC has experienced a general deterioration (except for a sudden and sharp increase observed around 2002) in both storage and sustainability, from ∆GWS = 16.79 cm/year and SIGWS = 0.46 (1985-1990) to ∆GWS = -28.96 cm/year and SIGWS = 0.008 (2007-2016); (2) the lowest value of groundwater sustainability in the HC appeared in the central and eastern regions (SIGWS = 0); (3) human activity was confirmed to be the dominant factor driving the processes of deterioration in groundwater sustainability in the HC, and during the research period, it is striking that relatively limited "positive" effects of the water management project were detected on the regional groundwater resource; this result indicates that damaged groundwater sustainability cannot be easily reversed unless a long-term management policy is implemented. This study also proves that GRACE gravity satellite data has great application potential in groundwater sustainability evaluation in arid regions, especially in developing countries where in-situ data are scarce, and highlights the importance of joint management of surface water and groundwater, in groundwater sustainability management.

6.
Cytometry A ; 97(1): 31-38, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31403260

RESUMO

Pathological diagnosis plays an important role in the diagnosis and treatment of hepatocellular carcinoma (HCC). The traditional method of pathological diagnosis of most cancers requires freezing, slicing, hematoxylin and eosin staining, and manual analysis, limiting the speed of the diagnosis process. In this study, we designed a one-dimensional convolutional neural network to classify the hyperspectral data of HCC sample slices acquired by our hyperspectral imaging system. A weighted loss function was employed to promote the performance of the model. The proposed method allows us to accelerate the diagnosis process of identifying tumor tissues. Our deep learning model achieved good performance on our data set with sensitivity, specificity, and area under receiver operating characteristic curve of 0.871, 0.888, and 0.950, respectively. Meanwhile, our deep learning model outperformed the other machine learning methods assessed on our data set. The proposed method is a potential tool for the label-free and real-time pathologic diagnosis. © 2019 International Society for Advancement of Cytometry.

7.
J Nanosci Nanotechnol ; 20(3): 1375-1382, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492297

RESUMO

This work reports the synthesis, radiolabeling and imaging studies of iodine-124 labeled peptide modified gold nanoclusters (AuNCs) as positron emission tomography (PET) tracer for lung cancer. The novel modified Au nanoclusters were successfully synthesized by conjugation of tumortargeting peptide luteinizing hormone releasing hormone (LHRH) to human serum albumin (HAS) as a scaffold, resulting in 73% labeling yield of 124I-LHRH-HSA AuNCs. After rapid purification, the radiochemical purity was above 98%. Dynamic PET study in normal rats showed high liver accumulation and rapid lung clearance. Both the PET and fluorescence imaging in A549 xenografted tumor model demonstrated certain amount of tumor uptake. In orthotopic lung cancer model, the tumor sites could be clearly visualized between 2 to 5 hours in PET images. The higher radioactivity concentration in the left lung which inoculated orthotopic tumor than right lung also exhibited the targeting properties. The biological properties of this iodine-124 labeled nanoclusters afford potential applications for early diagnosis of lung cancer with PET.

8.
Echocardiography ; 37(1): 77-85, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31872923

RESUMO

PURPOSE: We set out to undertake a preliminary assessment of the left ventricular hemodynamic status with right ventricular double-chamber pacing by energy loss (EL), wall shear stress (WSS), and circulation intensity (CIR) of vector flow mapping (VFM). We also planned to evaluate the value of VFM technology by measuring cardiac function after pacemaker implantation. METHOD: Data from 58 patients living with right ventricular double-chamber (right ventricular septal) pacemakers as well as 58 healthy volunteers matched in age and gender were collected. The EL, numbers of vortex cycles (n), area (A), CIR, and WSS of the left ventricle with different phases of the same cardiac cycle were obtained. RESULTS: The EL of the left ventricle was significantly higher in the pacemaker group than the control group at partial section of atrial contraction (AC), isovolumetric contraction (IVC), and rapid ejection (RE) (P < 0.05). The WSS of the left ventricle was significantly lower in the pacemaker group than the control group at part of the section in the rapid filling (RF), the AC, IVC, and RE phase (P < 0.05). DISCUSSION: EL in the left ventricular was significantly increased, while related WSS was significantly decreased in patients with right ventricular double-chamber pacing. Our exploration of the state of the flow field in the left ventricular cavity revealed that the implantation of the right ventricular double-chamber pacemaker led to an abnormal left ventricular hemodynamic state, reducing the left ventricular systolic efficiency.

9.
Mar Drugs ; 17(12)2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31795427

RESUMO

Marine-derived antioxidant polysaccharides have aroused extensive attention because of their potential nutritional and therapeutic benefits. However, the comprehensive comparison of identified marine-derived antioxidant polysaccharides is still inaccessible, which would facilitate the discovery of more efficient antioxidants from marine organisms. Thus, this review summarizes the sources, chemical composition, structural characteristics, and antioxidant capacity of marine antioxidant polysaccharides, as well as their protective in vivo effects mediated by antioxidative stress reported in the last few years (2013-2019), and especially highlights the dominant role of marine algae as antioxidant polysaccharide source. In addition, the relationships between the chemical composition and structural characteristics of marine antioxidant polysaccharides with their antioxidant capacity were also discussed. The antioxidant activity was found to be determined by multiple factors, including molecular weight, monosaccharide composition, sulfate position and its degree.

10.
J Clin Ultrasound ; 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31833078

RESUMO

PURPOSE: The aim of this study was to investigate myocardial dysfunction and mechanical abnormalities in young patients with Graves' disease before therapy, using two-dimensional speckle tracking echocardiography. METHODS: We performed a comprehensive transthoracic echocardiographic examination, including segmental and global radial strain, and time-to-peak radial strain, in 47 young patients with hyperthyroidism and 34 healthy adults. The time-to-peak radial strain was corrected by RR interval. The variables derived from radial myocardial deformation by the six-basal, six-mid, and six-apical segmental model were compared to investigate the difference of the myocardial function between the two groups. RESULTS: Early diastolic mitral inflow velocity, E/A ratio, early diastolic mitral annular velocity, and e'/a' ratio were lower in patients with Graves' disease than in controls. The left ventricular end-diastolic volume, left ventricular end-systolic volume, stroke volume, cardiac output, heart rate, late diastolic mitral inflow velocity, and late diastolic mitral annular velocity were slightly higher in patients than in controls. Radial strain, global radial strain, and corrected time-to-peak radial strain were lower in the patient group. CONCLUSIONS: The decreased radial strain, global radial strain, and corrected time-to-peak radial strain in young patients with newly diagnosed hyperthyroidism due to Graves' disease could serve as an early sign of subclinical cardiac involvement.

11.
Sleep Breath ; 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31858391

RESUMO

PURPOSE: This prospectively designed study aimed to investigate the association between sleep duration and overweight in a cohort of Chinese adolescents. METHODS: A school-based cohort study with a 2-year follow-up was conducted among Chinese adolescents in Ningbo region (China). For the baseline study, 1901 school-aged Chinese children aged 12-13 years were recruited. Finally, 1510 adolescents were successfully reinterviewed in October 2018. Participants were asked to complete a self-administered questionnaire, and their heights and weights were directly measured. RESULTS: Overweight adolescents had shorter sleep duration or later bedtimes than non-overweight children in baseline (P < 0.05). In the multivariable linear regression analysis, sleep duration was marginally significantly correlated with body mass index (BMI) at baseline and significantly correlated with this parameter at a 2-year follow-up (ß = - 0.23, 95% confidence interval (CI): - 0.51 to 0.04, P < 0.1; ß = - 0.27, 95% CI: - 0.42 to - 0.11, P < 0.05, respectively). After adjusting for potential confounders, the multivariable logistic regression analysis revealed associations of a longer sleep duration at baseline with a reduced likelihood of participants being overweight both at baseline and at follow-up (adjusted odds ratio (AOR) = 0.81, 95% CI: 0.66 to 1.00, P = 0.05; AOR = 0.43, 95% CI:0.24 to 0.76, P < 0.05, respectively). CONCLUSIONS: Shorter sleep was associated with an increased likelihood of being overweight in Chinese adolescents, while a 1-h decrease in sleep per night led to a more than 50% increase in the overweight risk at the 2-year follow-up.

12.
Elife ; 82019 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-31763980

RESUMO

The human face represents a combined set of highly heritable phenotypes, but knowledge on its genetic architecture remains limited, despite the relevance for various fields. A series of genome-wide association studies on 78 facial shape phenotypes quantified from 3-dimensional facial images of 10,115 Europeans identified 24 genetic loci reaching study-wide suggestive association (p < 5 × 10-8), among which 17 were previously unreported. A follow-up multi-ethnic study in additional 7917 individuals confirmed 10 loci including six unreported ones (padjusted < 2.1 × 10-3). A global map of derived polygenic face scores assembled facial features in major continental groups consistent with anthropological knowledge. Analyses of epigenomic datasets from cranial neural crest cells revealed abundant cis-regulatory activities at the face-associated genetic loci. Luciferase reporter assays in neural crest progenitor cells highlighted enhancer activities of several face-associated DNA variants. These results substantially advance our understanding of the genetic basis underlying human facial variation and provide candidates for future in-vivo functional studies.

13.
Am J Cancer Res ; 9(10): 2064-2078, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31720075

RESUMO

The activating receptor natural killer group 2, member D (NKG2D) is involved in both innate and adaptive immunities, and functions as a "master switch" in determining the activation status of natural killer (NK) cells. NKG2D binds to a diverse family of ligand molecules, which are only expressed at low levels in normal cells but can be upregulated by a cellular stress response. The NKG2D-NKG2D ligand (NKG2DL) pathway has been considered to be promising target for immunotherapy because of the selective expression of "stress-induced ligands" on tumor cells and the strong NK cell activating potency of NKG2D. Diverse strategies that are aimed at targeting the NKG2D pathway for cancer therapy are based on a thorough understanding of this mechanism, as well as that of NKG2D-mediated cancer immunity. In this review, we summarize the major findings regarding the antitumor immune response mediated by the NKG2D receptor and its ligands, and discuss the potential clinical applications of targeting the NKG2D/NKG2DL pathway for immunotherapy in cancer patients.

14.
Life Sci ; 236: 116899, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31614145

RESUMO

AIMS: The aim of our study is to illustrate the role of amphiregulin in trophoblast invasiveness and underlying signal cascades. MAIN METHODS: An immortalized human early extravillous cell line, HTR-8/SVneo, was used for this investigation. Matrigel-transwell invasion assay was used for testing the effects of amphiregulin on cell invasiveness. MMP9 and MMP2 mRNA expression level and activity were measured using Rt-qPCR and zymographic analysis. Cell signals involved in the invasion process were verified using western blot and specific inhibitors. KEY FINDINGS: Our results showed that amphiregulin could promote HTR-8/SVneo cell invasiveness without interfering cell proliferation, and significantly upregulate the expression of MMP9 and TIMP-1 mRNAs as well as the ratio of MMP9/TIMP-1. Using specific inhibitors for MEK and PI3K signaling further indicated that, both ERK1/2 and Akt signal pathways were required for amphiregulin-induced cell invasiveness. The co-ordination between ERK1/2 and Akt signaling pathway was needed for the upregulation of MMP9 mRNA, while ERK1/2 was more essential for the upregulation of TIMP-1 mRNA. Meanwhile, we first put forward that the deficiency of amphiregulin expression in trophoblast might be compensated by the upregulation of epidermal growth factor receptor (EGFR) and heparin-binding EGF (HB-EGF) mRNA. SIGNIFICANCE: ERK1/2 and Akt signaling pathways mediate amphiregulin-induced upregulation of MMP9 mRNA and the MMP9/TIMP-1 ratio, which subsequently contribute to amphiregulin-promotion of HTR-8/SVneo cell invasion.


Assuntos
Anfirregulina/farmacologia , Metaloproteinase 9 da Matriz/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Trofoblastos/metabolismo , Trofoblastos/patologia , Movimento Celular , Proliferação de Células , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Humanos , Metaloproteinase 9 da Matriz/genética , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Gravidez , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais , Inibidor Tecidual de Metaloproteinase-1/genética
15.
ACS Appl Mater Interfaces ; 11(45): 41829-41841, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31617343

RESUMO

Photodynamic therapy (PDT) is an encouraging alternative therapy for melanoma treatment and Ce6-mediated PDT has shown some exciting results in clinical trials. However, PDT in melanoma treatment is still hampered by some melanoma's protective mechanisms like antiapoptosis mechanisms and treatment escape pathways. Combined therapy and enhancing immune stimulation were proposed as effective strategies to overcome this resistance. In this paper, a Chlorin-based photoactivable Galectin-3-inhibitor nanoliposome (PGIL) was designed for enhanced Melanoma PDT and immune activation of Natural Killer (NK) cells. PGIL were synthesized by encapsulating the photosensitizer chlorin e6 and low molecular citrus pectin in the nanoliposome to realize NIR-triggered PDT and low molecular citrus pectin (LCP) release into the cytoplasm. The intracellular release of LCP inhibits the activity of galectin-3, which increases the apoptosis, inhibits the invade ability, and enhances the recognition ability of Natural Killer (NK) cells to tumor cells in melanoma cells after PDT. These effects of PGIL were tested in cells and nude mice, and the mechanisms during the in vivo treatment were preliminarily studied. The results showed that PGIL can be an effective prodrug for melanoma therapy.

16.
J Insect Physiol ; 119: 103964, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31604063

RESUMO

It is now widely accepted that Hexapoda emerged from Crustacea. Compared to the ubiquitous calcified exoskeleton in crustaceans, a mineralized cuticle in insects is extremely rare. Catecholamine-driven protein cross-links play a leading role in the sclerotization of insect cuticle. In this study, mineralization was discovered in the pupal cuticle of Bactrocera dorsalis (Diptera: Tephritidae), a common pest of fruit farms. We mainly profiled the features of mineralized pupal cuticles from B. dorsalis and its white mutant B. dorsaliswh and unmineralized cuticle from Musca domestica using high-resolution field emission scanning electron microscopy (SEM) and transmission electron microscopy (TEM) combined with structural analysis involving infrared (IR) spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and synchrotron X-ray absorption near-edge structure (XANES) spectroscopy. We also compared the thermodynamic and mechanical properties of different pupal cuticles. The results showed that the pupal cuticles of B. dorsalis contain a phase of stable amorphous calcium phosphate (ACP) with a high level of magnesium, which is mainly distributed in the exocuticle and assists in the formation of a graded, stiffened cuticle structure. Unexpectedly, this ACP possesses a very low Ca/P ratio and has a composition similar to that of CaHPO4·2H2O. The degree of mineralization in the pupal cuticle of B. dorsaliswh (approximately 22 wt%) is significantly greater than that of wild-type B. dorsalis (approximately 12 wt%), which indicates that there may be a connection between the biomineralization and tyrosine-mediated tanning pathways. These findings provide new evidence for the mineralization of the insect cuticle, which may shed new light on the evolutionary mechanism underlying the divergence of cuticle sclerotization between insects and crustaceans.

17.
Aging (Albany NY) ; 11(20): 9013-9024, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619582

RESUMO

Steroidogenic acute regulatory protein (StAR) mediates the rate-limiting step in ovarian steroidogenesis and progesterone (P4) synthesis. Melatonin and its receptors are expressed in human granulosa cells, and have been shown to influence basal P4 production. However, previous studies addressing the regulation of StAR expression by melatonin and its impact on P4 secretion yielded contradictory results. Here, we demonstrate that melatonin upregulates StAR expression in primary cultures of human granulosa-lutein (hGL) cells obtained from women undergoing in vitro fertilization (IVF). Using pharmacological inhibitors, we show that the stimulatory effect of melatonin on StAR expression is mediated via both MT1 and MT2 melatonin receptors. Melatonin exposure activates the PI3K/AKT signaling pathway and its inhibition attenuates the stimulatory effect of melatonin on StAR expression. Moreover, siRNA-mediated knockdown of StAR abolishes melatonin-induced P4 production. Importantly, clinical analyses demonstrate that melatonin levels in human follicular fluid are positively correlated with P4 levels in serum. By illustrating the potential physiological role of melatonin in the regulation of StAR expression and P4 production in hGL cells, our results may serve to improve current strategies used to treat clinical infertility.

18.
Adv Sci (Weinh) ; 6(19): 1900775, 2019 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-31592413

RESUMO

Solution-processed 2D organic semiconductors (OSCs) have drawn considerable attention because of their novel applications from flexible optoelectronics to biosensors. However, obtaining well-oriented sheets of 2D organic materials with low defect density still poses a challenge. Here, a highly crystallized 2,9-didecyldinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene (C10-DNTT) monolayer crystal with large-area uniformity is obtained by an ultraslow shearing (USS) method and its growth pattern shows a kinetic Wulff's construction supported by theoretical calculations of surface energies. The resulting seamless and highly crystalline monolayers are then used as templates for thermally depositing another C10-DNTT ultrathin top-up film. The organic thin films deposited by this hybrid approach show an interesting coherence structure with a copied molecular orientation of the templating crystal. The organic field-effect transistors developed by these hybrid C10-DNTT films exhibit improved carrier mobility of 14.7 cm2 V-1 s-1 as compared with 7.3 cm2 V-1 s-1 achieved by pure thermal evaporation (100% improvement) and 2.8 cm2 V-1 s-1 achieved by solution sheared monolayer C10-DNTT. This work establishes a simple yet effective approach for fabricating high-performance and low-cost electronics on a large scale.

19.
Nat Commun ; 10(1): 4151, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31515483

RESUMO

Efficient low-grade heat recovery can help to reduce greenhouse gas emission as over 70% of primary energy input is wasted as heat, but current technologies to fulfill the heat-to-electricity conversion are still far from optimum. Here we report a direct thermal charging cell, using asymmetric electrodes of a graphene oxide/platinum nanoparticles cathode and a polyaniline anode in Fe2+/Fe3+ redox electrolyte via isothermal heating operation. When heated, the cell generates voltage via a temperature-induced pseudocapacitive effect of graphene oxide and a thermogalvanic effect of Fe2+/Fe3+, and then discharges continuously by oxidizing polyaniline and reducing Fe3+ under isothermal heating till Fe3+ depletion. The cell can be self-regenerated when cooled down. Direct thermal charging cells attain a temperature coefficient of 5.0 mV K-1 and heat-to-electricity conversion efficiency of 2.8% at 70 °C (21.4% of Carnot efficiency) and 3.52% at 90 °C (19.7% of Carnot efficiency), outperforming other thermoelectrochemical and thermoelectric systems.

20.
J Dermatol Sci ; 96(1): 42-49, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31522824

RESUMO

BACKGROUND: The progression of human skin aging has a strong genetic basis. However, recent studies have mainly focused on Caucasian populations and we have thus performed a genetic association study on skin aging signs in Han Chinese population. OBJECTIVE: To investigate genetic risk factors in skin aging in Han Chinese female, we performed a genome-wide association study. METHODS: We collected genotype data from 1534 Han Chinese female from Taizhou cohort and evaluated 15 skin aging phenotypes by using the validated skin aging SCINEXA™ score. Genetic associations were tested by linear and logistic regression analyses and adjusted for potential confounders. RESULTS: Six genomic regions significantly associated with a risk for skin aging were revealed : 6q24.2 (rs3804540, P=4.6×10-9, additive model) with size of pigmented spots on forehead, 10q26.13 (rs4962295, P=1.9 ×10-8, additive model) with wrinkles under eyes, 15q21.1 (rs28392847, P=1.6×10-8, additive model) with crow's feet, 2p25.1 (rs191497052, P=5.5×10-9, dominant model) with telangiectasia, 13q34 (rs3825460, P=3.7×10-8, dominant model) with size of pigmented spots on cheeks and 16p13.11(rs76053540, P=5.0×10-9, dominant model) with nasolabialfold. The signal on 15q21.1 was replicated in the meta-analysis with two independent Caucasian cohorts (P=8.6×10-10). We have also successfully replicated in our cohort an association between SNP rs1048943 of gene CYP1A1 (P=7.1 × 10-4) and pigmented spots on cheeks previously described in Caucasian cohort. CONCLUSIONS: Our study has identified new genetic risk factors for signs of skin aging in the Han Chinese. This study suggests there are differences in genetic susceptibility to skin aging between Caucasians and the Han Chinese.

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