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1.
Electrophoresis ; 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32333411

RESUMO

Microhaplotypes are a new promising type of forensic genetic marker. Without the interference of stutter and high mutation rates as for STRs, and with short amplification lengths and a higher degree of polymorphism than single SNP, microhaplotypes composed of two SNPs, SNP-SNP, have a strong application potential. Currently, the most common method to detect microhaplotypes is massive parallel sequencing. However, the cost and extensive use of instruments limit its wide application in forensic laboratories. In this study, we screened 23 new SNP-SNP loci and established a new detection method by combining a multiplex amplification refractory mutation system-based PCR (ARMS-PCR) and SNaPshot technology based on CE. First, we introduced an additional deliberate mismatch at the antepenultimate base from the 3' end of primers when designing ARMS-PCR for SNP 1 (the first SNP of the SNP-SNP). Then, single base extension primers for SNaPshot assay were designed next to the position of SNP 2 (the second SNP). Finally, 15 loci were successfully built into four panels and these loci showed a relatively high level of polymorphism in the Southwest Chinese Han population. All the loci had an average probability of informative genotypes (I value) of 0.319 and a combined discrimination power of 0.999999999. Therefore, this new detection system will provide a valuable supplement to current methods.

2.
Opt Express ; 28(1): 503-510, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-32118976

RESUMO

An exceptional point occurring in a tailor-made lossy optical system has been recently found to alter optical properties in counter-intuitive ways. In the context of tunable plasmonic devices, exceptional points can be useful as a driving mechanism to enhance tunability. Here, we experimentally demonstrate how a plasmonic exceptional point can be incorporated in metasurface Q-plates to have the generated vortex beam tuned through a change of structural parameter. We have observed an orbital rotation in the far-field by 45 degrees in crossing the exceptional point. We expect a new generation of tunable plasmonic devices in polarization control, beam structuring and holograms, which can take advantage of the huge sensitivity from exceptional points.

3.
Ann Diagn Pathol ; 46: 151493, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32179442

RESUMO

Cervical squamous cell carcinoma develops through a series of stages, including low-grade squamous intraepithelial lesions (LSIL), high-grade squamous intraepithelial lesions (HSIL), microinvasive squamous cell carcinoma (MISCC), and invasive squamous cell carcinoma (ISCC). The difference between HSIL and MISCC is the appearance of microinvasion, which determines the treatment for patients. However, sometimes it is difficult to differentiate HSIL from MISCC in morphology, and no effective markers are available to help determine microinvasion. Here, we evaluated the expression patterns of podoplanin in cervical tissues by immunohistochemistry staining. Results showed that podoplanin was specifically expressed in a continuous or discontinuous linear pattern within the basal layer of cells from normal cervical squamous epithelium (NS) (100%, 96/96) and HSIL (81%, 57/70). However, its expression was completely absent in microinvasive lesions (0%, 72/72), and the location of podoplanin expression loss was consistent with that of microinvasive lesions. Thus, for HSIL with positive podoplanin expression, the sudden loss of podoplanin represents the occurrence of early invasion. Furthermore, podoplanin was expressed in 3.4% (4/118) of ISCC, and its expression was not correlated with the age of the patient, tumor size, differentiation, FIGO stage, depth of invasion, lymph node, or distant metastasis. The prognosis of patients with positive podoplanin was slightly better than those without it (p > 0.05). Therefore, we found that podoplanin, as a new specific marker for the basal layer cells of cervical squamous epithelium, could assist the diagnosis of microinvasion in cervical squamous cell carcinoma. The specific staining pattern of podoplanin provides the possibility of clinical application in the future.

4.
Nano Lett ; 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32182076

RESUMO

Circular phase-dichroism (CPD) has been suggested for the characterization of chiral metasurfaces in supplementing the conventional circular dichroism (CD). Conventional CD probes the bulk properties while the CPD, reported recently in 2D chiral metasurfaces using an air-gap Fabry-Perot setup, is based on the surface properties. Here we propose and demonstrate a robust birefringent interference approach to obtain the CPD by replacing the air-gap with a uniaxial birefringent material in which interference is realized by the difference in the refractive indexes for the ordinary and extraordinary components of the material. We measure the transmission phases of metasurfaces fabricated on birefringent sapphire substrates and obtain clear CPDs for chiral metasurfaces but vanishing for achiral metasurfaces. Importantly, our approach can be applied to metasurfaces fabricated on nonbirefringent substrates by add-on birefringent materials. We confirm our results by a Jones matrix method using data obtained from full-wave simulations, and good agreements with experiments are obtained.

5.
Cell Prolif ; 53(3): e12764, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32077168

RESUMO

OBJECTIVES: microRNA-29 (miR-29) family have shown different expression patterns in cardiovascular diseases. Our study aims to explore the effect and mechanism of miR-29 family on cardiac development. MATERIALS AND METHODS: A total of 13 patients with congenital heart disease (CHD) and 7 controls were included in our study. Tissues were obtained from the right ventricular outflow tract (RVOT) after surgical resection or autopsy. The next-generation sequencing was applied to screen the microRNA expression profiles of CHD. Quantitative RT-PCR and Western blot were employed to measure genes expression. Tg Cmlc2: GFP reporter zebrafish embryos were injected with microRNA (miRNA) to explore its role in cardiac development in vivo. Dual-luciferase reporter assay was designed to validate the target gene of miRNAs. CCK-8 and EdU incorporation assays were performed to evaluate cardiomyocyte proliferation. RESULTS: Our study showed miR-29b-3p expression was significantly increased in the RVOT of the CHD patients. Injection of miR-29b-3p into zebrafish embryos induced higher mortality and malformation rates, developmental delay, cardiac malformation and dysfunction. miR-29b-3p inhibited cardiomyocyte proliferation, and its inhibitor promoted cardiomyocyte proliferation in vitro and in vivo. Furthermore, we identified that miR-29b-3p influenced cardiomyocyte proliferation by targeting NOTCH2, which was down-regulated in the RVOT of the CHD patients. CONCLUSION: This study reveals that miR-29b-3p functions as a novel regulator of cardiac development and inhibits cardiomyocyte proliferation via NOTCH2, which provides novel insights into the aetiology and potential treatment of CHD.


Assuntos
Cardiopatias Congênitas/genética , MicroRNAs/genética , Miócitos Cardíacos/patologia , Receptor Notch2/genética , Animais , Proliferação de Células , Células Cultivadas , Pré-Escolar , Regulação para Baixo , Feminino , Coração/embriologia , Cardiopatias Congênitas/patologia , Humanos , Lactente , Masculino , Camundongos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Regulação para Cima , Peixe-Zebra
6.
Inorg Chem ; 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32068394

RESUMO

Hexagon-like MAX-phase V4AlC3 single crystals grown by a high-temperature flux method were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopy (EDX). We report, for the first time, the first-order Raman spectra (RS) of V4AlC3 single crystals experimentally and theoretically. Via the combination of the results of thermogravimetric analysis, differential scanning calorimetry, XRD, FE-SEM, and EDX, the oxidation performance and mechanism of V4AlC3 single crystals between 300 and 1473 K in air were clarified. Importantly, we carefully investigated the room-temperature corrosion behaviors of V4AlC3 single crystals in concentrated acids [HCl, H2SO4, hydrofluoric acid (HF), and HNO3] and alkalis (NaOH and KOH). V4AlC3 single crystals are stable in concentrated HCl, H2SO4, and NaOH but unstable and even dissolved completely in concentrated KOH and HNO3. In particular, our XRD, RS, FE-SEM, and EDX results have confirmed that HF can dissolve the Al layers of V4AlC3 single crystals but cannot corrode V4C3 layers at room temperature, which eventually led to the formation of macroscopic V4C3Tx MXene. This reported approach of macro-sized V4C3Tx MXene can be adapted for obtaining other macroscopic MXenes and will inspire plenty of theoretical and experimental investigations to explore their intrinsic nature and applications, especially for electronic and photonic applications.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31985447

RESUMO

Magnetic resonance imaging (MRI) vertebral localization, identification, and segmentation are important steps in the automatic analysis of spines. Due to the similar appearances of vertebrae, various pathological patterns and imaging artifacts, the accurate segmentation, localization and identification of vertebrae remain challenging. With the emergence of convolutional neural networks, deep learning based methods have been successfully developed to address these three tasks. However, previous methods solve the three tasks independently, ignoring the intrinsic correlation among them. In this paper, we propose a multi-task relational learning network (MRLN) that utilizes both the relationships between vertebrae and the relevance of the three tasks. Specifically, we combine a dilation convolution group and LSTM to learn the prior knowledge that the identification information is always in a fixed order for spine images. A co-attention module is proposed to learn the localization-guided segmentation attention and segmentation-guided localization attention, which improves segmentation and localization performance based on the identification information. In addition, a novel multi-task loss function named XOR loss is been create. This method was evaluated on a dataset which includes multiple MRI modalities (T1 and T2), various fields of view and four variety (intensity variety, pathological variety, uneven variety, and size variety, shown in Fig. 1). For vertebrae segmentation, the average Dice score was 95.38%. The anatomical identification accuracy is 93.55% and mean localization error is 2.6265 mm. Overall, the advantage of our framework is that it can fully make use of the relationships of different vertebrae and three tasks simultaneously, which makes it an attractive method for the automatic analysis of spine.

8.
Gene ; 733: 144271, 2020 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-31809841

RESUMO

Aoluguya Reindeer is the only reindeer population in China. In recent years, habitat loss and inbreeding have led to population decline, and population growth has been slow, maintaining a thousand or so. To better protect the Aoluguya Reindeer and improve its fecundity, we have introduced reindeer from Finland, crossbreeding help us to reach this goal. However, it is lacking in the study of genetic diversity of reindeer in China and Finland. Therefore, we used the partial sequences of the D-loop region of mitochondrial DNA to analyze the genetic diversity of Chinese reindeer (Aoluguya Reindeer) and the introduced Finnish reindeer, and identified twenty-six haplotypes, including nineteen in China, five in Finland, and two in Russia. There is no shared haplotype among them. The nucleotide diversity of Aoluguya Reindeer is 0.00752, which is significantly lower than that of reindeer in Finland and other countries. The haplotype and phylogenetic analysis show that reindeer from different geographical origins are not clustered completely according to geographical distribution. Aoluguya Reindeer populations and the introduced reindeer herds from Finland are all closely related to the reindeer from Russia. AMOVA analysis showed that there was significant differentiation between reindeer populations in China and Finland, and mismatch analysis showed that both populations had not experienced expansion. In this study, we identified the genetic diversity of Aoluguya Reindeer and the introduced reindeer, and provided a scientific basis for the conservation and breeding of Aoluguya Reindeer resources.

9.
Environ Pollut ; 258: 113654, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31806457

RESUMO

Livestock manure is a reservoir for antibiotic resistance genes (ARGs), and aerobic composting is used widely for recycling animal manure. This study investigated the effects of adding nano-zerovalent iron (nZVI) at 0, 100, and 1000 mg/kg on the fates of ARGs and mobile genetic elements (MGEs) during swine manure composting. Under nZVI at 100 mg/kg, the relative abundances of sul1, sul2, dfrA7, ermF, and ermX decreased by 33.26-99.31% after composting, and the relative abundances of intI2 and Tn916/1545 decreased by 95.59% and 97.65%, respectively. Most of the ARGs and MGEs co-occurred and they had strong correlations with each other. The bacterial community structure was significantly separated by the composting periods, and they clustered together under different treatments in the same phase. Network analysis showed that Solibacillus, Clostridium_sensu_stricto_1, Terrisporobacter, Romboutsia, Turicibacter, Lactobacillus, Planococcus, Dietzia, and Corynebacterium_1 were common potential hosts of ARGs and MGEs. Redundancy analysis suggested that MGEs had key effects on the variations in the relative abundances of ARGs. Adding 100 mg/kg nZVI could reduce the environmental risk of ARGs by decreasing the abundances of MGEs.

10.
Biol Open ; 8(12)2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31796423

RESUMO

Cardiac muscle troponin T (Tnnt2) mediates muscle contraction in response to calcium ion dynamics, and Tnnt2 mutations are associated with multiple types of cardiomyopathy. Here, we employed a zebrafish model to investigate the genetic replenishment strategies of using conditional and inducible promoters to rescue the deficiencies in the heart. tnnt2a mutations were induced in zebrafish via the CRISPR/Cas9 technique, and the mutants displayed heart arrest and dilated cardiomyopathy-like phenotypes. We first utilized the classic myocardial promoter of the myl7 and TetOn inducible system to restore tnnt2a expression in myocardial tissue in tnnt2a mutant zebrafish. However, this attempt failed to recover normal heart function and circulation, although heart pumping was partially restored. Further analyses via both RNA-seq and immunofluorescence indicated that Tnnt2a, which was also expressed in a novel group of myl7-negative smooth muscle cells on the outflow tract (OFT), was indispensably responsible for the normal mechanical dynamics of OFT. Lastly, tnnt2 expression induced by OFT cells in addition to the myocardial cells successfully rescued heart function and circulation in tnnt2a mutant zebrafish. Together, our results reveal the significance of OFT expression of Tnnt2 for cardiac function and demonstrate zebrafish larva as a powerful and convenient in vivo platform for studying cardiomyopathy and the relevant therapeutic strategies.

11.
Sci Rep ; 9(1): 15783, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31673112

RESUMO

Diamondene is a new kind of two dimensional carbon allotrope with excellent properties and passivation approaches are often used to reduce the extremely high pressure required during its fabrication. When a one-end-clamped diamondene ribbon is hydrogenated on one surface, the ribbon tends to bend and vibrate due to asymmetric layout of C-H bonds on two surfaces. In the present work, the vibration behavior, including natural curvatures and vibration frequencies of diamondene ribbons, were investigated by molecular dynamics simulations. Results indicate that the natural curvature radius of a narrow diamondene ribbon is close to 12.17 nm at a temperature below 150 K, which is essential for fabricating an arc nanodevice. The first order frequency (f1) of a cantilever beam made from the ribbon follows traditional beam vibration theory if the slenderness ratio is low. In particular, f1 increases logarithmically at temperature below 50 K, but changes slightly between 50 K and 150 K. It suggests a design scheme for a nanoresonator with temperature-controlled frequency.

12.
Opt Express ; 27(15): 21717-21728, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31510243

RESUMO

Surface plasmon resonance (SPR) has found wide applications in sensing down to molecular level due to its extreme sensitivity to change of dielectric properties. An unavoidable effect in SPR is surface deformation (thermal bump) due to local heating by incident laser light used in SPR. In addition, changes in the reflection phase from the metal film used in SPR could also contribute to the SPR signal, and thus proper handling of the SPR signal is very important in order to broaden the potential applications of SPR. Here we report a simple Fabry Perot (FP) interference technique for measuring, simultaneously, the thermal bump height as well as the reflection phase shift of gold film used in SPR. We find that the shift of the FP signal is dominated by the effect of the thermal bump while it is small for the effect of the reflection phase shift due to change of dielectric property of the metal. To support our experimental results, we have also performed model simulation for the SPR system and obtain good agreement with the experiment. As both amplitude and phase can be measured, our method could lead to better characterization of SPR and can also be applied to the study of active metasurfaces under external excitation.

13.
Endocr Pathol ; 30(4): 262-269, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31468286

RESUMO

Long non-coding RNAs (lncRNAs) participate in transcription and in epigenetic or post-transcriptional regulation of gene expression. They also have roles in epithelial to mesenchymal transition and in carcinogenesis. Because lncRNAs may also have a role in thyroid cancer progression, we examined a group of thyroid tumors which included papillary thyroid carcinomas and anaplastic thyroid carcinomas to determine the specific lncRNAs that were upregulated during thyroid tumor progression. An RT2 Profiler PCR Array Human Cancer Pathway Finder consisting of 84 lncRNAs (Qiagen) and fresh tissues of normal thyroid, PTCs, and ATCs with gene expression profiling was used to determine genes upregulated and downregulated in ATCs. Two of the most highly upregulated genes, prostate cancer antigen 3 (PCA3) and HOX antisense intergenic RNA myeloid 1 (HOTAIRM1 or HAM-1), were selected for further studies using a thyroid tissue microarray(TMA) with formalin-fixed paraffin-embedded tissues of normal thyroid (NT, n = 10), nodular goiters (NG, n = 10), follicular adenoma (FA, n = 32), follicular carcinoma (FCA, n = 28), papillary thyroid carcinoma (PTC, n = 28), follicular variant of papillary thyroid carcinoma (FVPTC, n = 28), and anaplastic thyroid carcinoma (ATC, n = 10). TMA sections were analyzed by in situ hybridization (ISH) using RNAscope technology. The results of ISH analyses were imaged with Vectra imaging technology and quantified with Nuance® and inForm® software. The TMA analysis was validated by qRT-PCR using FFPE tissues for RNA preparation. Cultured thyroid carcinoma cell lines (n = 7) were also used to analyze for lncRNAs by qRT-PCR. The results showed 11 lncRNAs upregulated and 7 downregulated lncRNAs more than twofold in the ATCS compared with PTCs. Two of the upregulated lncRNAs, PCA3 and HAM-1, were analyzed on a thyroid carcinoma TMA. There was increased expression of both lncRNAs in ATCs and PTCs compared with NT after TMA analysis. qRT-PCR analyses showed increased expression of both lncRNAs in ATCs compared with NT and PTCs. Analyses of these lncRNAs from cultured thyroid carcinoma cell lines by qRT-PCR showed the highest levels of lncRNA expression in ATCs. TGF-ß treatment of cultured PTC and ATC cells for 21 days led to increased expression of PCA3 lncRNA in both cell lines by day 14. These results show that the lncRNAs PCA3 and HAM-1 are upregulated during thyroid tumor development and progression and may function as oncogenes during tumor progression.

14.
J Phys Condens Matter ; 31(41): 415402, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31295737

RESUMO

We present a high-pressure study of type-II Dirac semimetal PtSe2 single crystals through synchrotron x-ray diffraction (XRD), electrical transport and Raman scattering measurements in diamond anvil cells with pressures up to 36.1-42.3 GPa, from which two critical pressure points associated with unusual electron-phonon coupling are unraveled. We show that both resistance and phonon linewidth of Raman modes display anomalies at the first critical pressure of P r ~ 10 GPa, in accordance with a scenario of pressure-induced disappearance/appearance of type-II/type-I Dirac points around P r predicted previously. The second critical pressure P c ~ 20 GPa may correspond to a structural crossover of PtSe2 from quasi-2D lattice to 3D network, which is revealed via detailed analysis of the structural parameters extracted from XRD refinement, Raman modes shifts as well as parameters from fitting of the low-temperature resistance. Our results demonstrate great tunability of PtSe2 via strain engineering, thanks to the single p-orbital manifold derived electronic states that are susceptible to out-of-plane and in-plane distances.

15.
Artif Cells Nanomed Biotechnol ; 47(1): 2838-2845, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31307228

RESUMO

Although titanium implants account for a large proportion of the commercial dental market, their bioactivity are inadequate in many applications. A micro- and nano- scale hierarchical surface topography of the implant is suggested for rapid osseointegration from the biomimetic perspective. Moreover, Zinc (Zn) is an essential element in the skeletal system. Thus, a micro/nanostructured TiO2/ZnO coating, produced by micro-arc oxidation, and hydrothermal treatment, and heat treatment, was designed to endow the implant surface with enhanced osteogenic capacity. Physiochemical properties and biological effects of this coating were investigated in our study. The annealed micro/nanostructured TiO2/ZnO coating exhibited higher hydrophilicity and fibronectin adsorption ability compared to the micro-arc oxidation modified TiO2 coating. SaOS-2 cells grown on the annealed micro/nanostructured TiO2/ZnO coating showed increased alkaline phosphatase activity and collagen secretion, and immunofluorescence labeling revealed an upregulation of osteopontin, collagen type ι and osteocalcin. The micro/nanostructure and incorporation of Zn were considered to perform positive effect on the enhanced osteogenic activity of SaOS-2 cells. In conclusion, the micro/nanostructured TiO2/ZnO structure is simple, stable, and easy to produce and scale up, has promising applications in the surface modification of titanium implants.


Assuntos
Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Nanoestruturas/química , Osteogênese/efeitos dos fármacos , Titânio/química , Óxido de Zinco/química , Adsorção , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fibronectinas/química , Humanos , Molhabilidade
16.
Materials (Basel) ; 12(13)2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31288399

RESUMO

Fluorescence imaging offers a new approach to visualize real-time details on a cellular level in vitro and in vivo without radioactive damage. Poor light stability of organic fluorescent dyes makes long-term imaging difficult. Due to their outstanding optical properties and unique structural features, graphene quantum dots (GQDs) are promising in the field of imaging for real-time tracking in vivo. At present, GQDs are mainly loaded on the surface of nanoparticles. In this study, we developed an efficient and convenient one-pot method to load GQDs into nanoparticles, leading to longer metabolic processes in blood and increased delivery of GQDs to tumors. Optical-magneto ferroferric oxide@polypyrrole (Fe3O4@PPy) core-shell nanoparticles were chosen for their potential use in cancer therapy. The in vivo results demonstrated that by loading GQDs, it was possible to monitor the distribution and metabolism of nanoparticles. This study provided new insights into the application of GQDs in long-term in vivo real-time tracking.

17.
Fish Shellfish Immunol ; 93: 232-239, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31340169

RESUMO

As an important economic mollusk in coastal areas, Octopus ocellatus dependents on innate immune system to resist the invasion of microorganisms. Lysozyme is a crucial effector owing to its significant lytic activity against bacterial pathogens during the immune responses. In this study, characteristic and immune function of an I-type lysozyme from O. ocellatus (OoLyz) was investigated. OoLyz shared a close relationship with the lysozymes from other bivalve mollusks. The mRNA of OoLyz exhibited a broad transcript in different tissues/organs, and with the greatest expression in hepatopancreas. The expression of OoLyz was significantly raised when O. ocellatus was infected by Vibrio anguillarum or Micrococcus luteus, suggesting OoLyz participated in innate immune response of host. Prokaryotic recombinant OoLyz (rOoLyz) exhibited obvious bacteriolysis ability towards both gram-negative bacteria V. anguillarum and Escherichia coli, and gram-positive bacteria M. luteus and Staphylococcus aureus. The bacteriolysis activities of rOoLyz towards gram-negative but not gram-positive bacteria was heat stable, indicating that OoLyz might clear gram-positive bacterium by enzyme-dependent mechanisms, but eliminate gram-negative microbe via enzymatic activity independent way. Scanning electron microscopy analysis showed that rOoLyz destroyed microbes by damaging cell wall. More importantly, the fact that rOoLyz could directly degrade the peptidoglycan, further revealed its bactericidal mechanism as a muramidase. Our results revealed the essential role of I-type lysozyme in the innate immunity of O. ocellatus, and shed new light to understand the mechanism of immune defense of mollusks.


Assuntos
Regulação da Expressão Gênica/imunologia , Imunidade Inata/genética , Muramidase/genética , Muramidase/imunologia , Octopodiformes/genética , Octopodiformes/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Feminino , Perfilação da Expressão Gênica , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/fisiologia , Masculino , Muramidase/química , Octopodiformes/microbiologia , Filogenia , Alinhamento de Sequência
18.
Inorg Chem ; 58(14): 9036-9042, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31246443

RESUMO

An excitonic insulating (EI) state is a fantastic correlated electron phase in condensed matter physics, driven by screened electron-hole interaction. Ta2NiSe5 is an excitonic insulator with a critical temperature (TC) of 328 K. In the current study, temperature-dependent Raman spectroscopy is used to investigate the phonon vibrations in Ta2NiSe5. The following observations were made: (1) an abnormal blue shift around TC is observed, which originates from the monoclinic to orthorhombic structural phase transition; (2) the splitting of a mode and two new Raman modes at 147 and 235 cm-1 have been observed with the formation of an EI state. With the help of first-principles calculations and temperature-dependent X-ray diffraction (XRD) experiments, it is found that the TaSe6 octahedra are "frozen" and the NiSe4 tetrahedra are greatly distorted below TC. Thus, it seems that the distortion of NiSe4 tetrahedra plays an important role in the strong electron-phonon coupling (EPC) in Ta2NiSe5, while the strong EPC, coupled with electron-hole interaction, opens the energy gap to form the EI state in Ta2NiSe5.

19.
Cell Metab ; 30(2): 374-384.e6, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31155493

RESUMO

Human organoid systems recapitulate in vivo organ architecture yet fail to capture complex pathologies such as inflammation and fibrosis. Here, using 11 different healthy and diseased pluripotent stem cell lines, we developed a reproducible method to derive multi-cellular human liver organoids composed of hepatocyte-, stellate-, and Kupffer-like cells that exhibit transcriptomic resemblance to in vivo-derived tissues. Under free fatty acid treatment, organoids, but not reaggregated cocultured spheroids, recapitulated key features of steatohepatitis, including steatosis, inflammation, and fibrosis phenotypes in a successive manner. Interestingly, an organoid-level biophysical readout with atomic force microscopy demonstrated that organoid stiffening reflects the fibrosis severity. Furthermore, organoids from patients with genetic dysfunction of lysosomal acid lipase phenocopied severe steatohepatitis, rescued by FXR agonism-mediated reactive oxygen species suppression. The presented key methodology and preliminary results offer a new approach for studying a personalized basis for inflammation and fibrosis in humans, thus facilitating the discovery of effective treatments.

20.
Genet Test Mol Biomarkers ; 23(7): 442-447, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31219360

RESUMO

Background: Single nucleotide polymorphisms (SNPs) within precursor microRNAs (miRNAs) can affect the expression of the miRNAs and may be involved in the pathogenesis of pulmonary tuberculosis (PTB) and extrapulmonary tuberculosis (EPTB). Aims: We investigated the potential associations among four precursor miRNA SNPs (miR-149 A>G, C>T; miR-196a2 C>T; miR-499 C>T) and both PTB and EPTB. Methods: The study included 380 PTB patients, 242 EPTB patients, and 606 healthy control (HC) subjects from a Chinese Han population. We determined the miRNA relative expression levels from 10 HCs and 10 tuberculosis (TB) patients by quantitative PCR. Results: We found that the PTB group had a significantly lower miR-149 level (p < 0.05) versus the HCs. The allele and genotype frequencies of the miR-149 SNPs were significantly different between the TB patients and the HC group. The C allele at the rs2292832 and the A allele at the rs71428439 locus were associated with susceptibility to EPTB. The C allele of rs2292832 was associated with an increased risk of EPTB compared with that of HCs (p < 0.01), and the A allele of rs71428439 was protective against EPTB (p < 0.01) and PTB (p < 0.01). Conclusions: We identified genetic polymorphisms in miR-149 that appear to be associated with susceptibility to both PTB and EPTB within a Chinese population.


Assuntos
MicroRNAs/genética , Polimorfismo de Nucleotídeo Único , Tuberculose Pulmonar/genética , Tuberculose/genética , Adulto , Alelos , China , Feminino , Expressão Gênica , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Precursores de RNA
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