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1.
Food Chem ; 303: 125404, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31466033

RESUMO

Fourier transform infrared (FTIR) spectroscopy calibrations were developed to simultaneously determine the multianalytes of five artificial sweeteners, including sodium cyclamate, sucralose, sodium saccharin, acesulfame-K and aspartame. By combining the pretreatment of the spectrum and principal component analysis, 131 feature wavenumbers were extracted from the full spectral range for modelling to qualitative and quantitative analysis. Compared to random forest, k nearest neighbour and linear discriminant analysis, support vector machine model had better predictivity, indicating the most effective identification performance. Furthermore, multivariate calibration models based on partial least squares regression were constructed for quantifying any combinations of the five artificial sweeteners, and validated by prediction data sets. As shown by the good agreement between the proposed method and the reference HPLC for the determination of the sweeteners in beverage samples, a promising and rapid tool based on FTIR spectroscopy, coupled with chemometrics, has been performed to identify and objectively quantify artificial sweeteners.

2.
Environ Technol ; : 1-8, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31580780

RESUMO

Enhancement of the transesterification efficiency of triglyceride has come under heated study in biodiesel-making industry. In this research, the NiMo/La-Al2O3 nanopowders have been prepared for producing biodiesel efficiently. The screening test showed that the NiMo/La-Al2O3 catalyst has the best catalytic activity for triglyceride transesterification. Besides, the process parameters including reaction temperature, time, oil-to-alcohol ratio and catalyst loading etc., also have been investigated for optimization of the transesterification process. The results showed that with 5 wt% of catalyst loading, and oil to methanol molar ratio of 1:9, the conversion yield of triglyceride could be up to 95.2% within 120 min at 160°C. The NiMo/La-Al2O3 catalyst has the outstanding recycle property, which proved that the prepared NiMo/La-Al2O3 powders can be suitable for biodiesels' production.

3.
J Mech Behav Biomed Mater ; 101: 103451, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31585350

RESUMO

High brittleness and lack osteogenesis are two major limitations of calcium phosphate cement (CPC) in application in bone defect reconstruction. Here we prepared a composite calcium phosphate cement by mixing N-acetyl cysteine loaded silk fibroin solution with α-tricalcium phosphate. In vitro cytology experiment revealed that SF-NAC/α-TCP could significantly increase the activity of exocrine ALP and up-regulated expression of bone-related genes. However, NAC up-regulated gene expression could be significantly suppressed by DKK1. We propose that NAC functioning as osteogenic factor by activating the Wnt/ß-catenin signaling pathway may be the possible mechanism of up-regulation of osteogenic genes. Bone regeneration in vivo shown in a rat femur defect was enhanced by the addition of NAC in SF/α-TCP. In addition, the combination intensity of cement-bone interface was improved. The combination SF-NAC/α-TCP might be developed into a promising tool for bone tissue repair in the clinic.

4.
Theriogenology ; 142: 104-113, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31586867

RESUMO

Heat stress causes reversible changes in tight junction proteins in immature Sertoli cells via inhibition of the AMPK signaling pathway; these effects are accompanied by an increase in the early apoptotic rate and decrease in the cell viability of Sertoli cells. Since heat stress is known to also cause oxidative damage, in the present study, we investigated whether the earlier mentioned effects of heat stress were brought about via the induction of oxidative stress in boar Sertoli cells. Immature Sertoli cells obtained from 3-week-old piglets were subjected to heat treatment (43 °C, 30 min), and the percentage of ROS-positive cells, the malonaldehyde (MDA) concentration, and the activity of the antioxidases, including superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and catalase (CAT) were measured. Next, the Sertoli cells were treated with N-acetyl-l-cysteine (NAC) (1 mmol/L, 2 h), an antioxidant agent, before they were exposed to heat stress. The effects of NAC on ROS accumulation, MDA levels, antioxidase activity, the CaMKKß-AMPK signaling pathway and expression of tight junction proteins were assessed. The results showed that heat stress reversibly increased the percentage of ROS-positive cells and MDA levels, and decreased the activity of SOD, GSH-Px, and CAT. Pretreatment with NAC abrogated these effects of heat stress. Additionally, NAC reversed the heat stress-induced decrease in the expression of CaMKKß and dephosphorylation of AMPK. NAC also obviously rescued the heat stress-induced downregulation of tight junction proteins (claudin-11, JAM-A, occludin, and ZO-1) both at the mRNA and protein level. In conclusion, the findings indicate that oxidative damage participates in heat stress-induced downregulation of tight junction proteins in Sertoli cells by inhibiting the CaMKKß-AMPK axis. Further, NAC reversed the effects of heat stress on tight junction proteins; this means that it has potential as a protective agent that can prevent reproductive dysfunction in boars under conditions of heat stress.

5.
Phys Med Biol ; 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31593930

RESUMO

Complex intra-fractional motion and deformation of the liver significantly impacts the accuracy of delivered dose in radiotherapy, and limits margin reduction, dose escalation and normal tissue sparing. A critical component of motion management is to accurately reconstruct tumor motion. In this study, we developed a Six Degree of Freedom Projection Marker Matching method (6-DoF PM3) to reconstruct translational and rotational liver tumor motion in a rotational treatment delivery, such as volumetric modulated arc therapy (VMAT). Specifically, we modeled the use of two gold markers implanted in a linear form. The four endpoints of the two gold linear markers were used as tracking surrogates. During delivery, kV x-ray projection images were acquired. A method was developed to automatically identify the 2D marker-endpoints on the projection images. To determine marker positions in 3D, we formulated an optimization problem. The objective function penalized the distance from the reconstructed 3D position of each fiducial marker endpoint to the corresponding straight line defined by the kV x-ray projection of the endpoints. Rigid translational and rotational motion of the liver tumor and motion smoothness along the temporal dimension were assumed. The optimization model was solved via a heuristic two-step alternating direction optimization approach. We performed a series of tests to evaluate different components of the method. For 2D marker endpoints identification, 95.6% of the marker endpoints were identified with an error ≦0.776mm along both u and v directions. For 3D reconstruction of motion in simulation studies, error of rotational angle was (0.5±6.5)×10-3degree without considering the 2D marker identification error. In the experimental end-to-end tests, the mean root-mean-square-error of the 3D reconstructed marker positions was 0.75mm and the mean error of rotational angle was within 1.7o. Our method can accurately determine intra-fractional liver tumor motion in rotational radiotherapy using kV projections of only two linear fiducial markers.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31583794

RESUMO

Stimuli-responsive photoluminescent materials have attracted particular attention due to their potential applications in security protection field, because the data or information recorded directly in materials with static luminescent outputs are usually visible under either ambient or UV light. Especially the ones with remote control over reversible luminescence ON-OFF switch behavior are extremely expected, as reversible visible/invisible information transformation can be achieved in a noninvasive manner. Herein, we realize reversible confidential information encryption and decryption via encapsulating photoswitchable diarylethene derivative into lanthanide metal-organic framework (MOF). The light triggers open and close isomerization of the diarylethene unit, which respectively regulates the inactivation and activation of the photochromic FRET process between diarylethene acceptor and lanthanide donor, resulting in reversible luminescence ON-OFF of lanthanide emitting center in MOF host. This photoresponsive host-guest system allows for reversible multiple information encryption and decryption by simply alternating the exposure to UV and visible lights.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31589397

RESUMO

We synthesized three conjugated polycarbazole porous organic frameworks named o-Cz-POF, m-Cz-POF and p-Cz-POF for hydrocarbon fuels adsorptive desulfurization. The carbazole building blocks possessed ortho, meta, and para steric configuration, which resulting in POFs exhibited adjustable specific surface area and pore structure. Adsorption kinetics experiments and DFT calculations were carried out to understand the competitive adsorption of 3-methylthiophene and octane in the Cz-POF. The instantaneous adsorption rate and adsorption energy calculation analyses gave a convincing demonstration on preferential selective adsorption of 3-methylthiophene in Cz-POFs. Furthermore, the fixed-bed breakthrough experiment demonstrated that the Cz-POFs can selectively adsorb 3-methylthiophene efficiently and hydrocarbon fuel with sulfide content close to 0 ppm was obtained. The features of high stability and high desulfurization efficiency of Cz-POFs make them hold the promise as a new type of porous adsorbents for the ultra-deep adsorption desulfurization.

8.
Nat Commun ; 10(1): 4602, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601796

RESUMO

The success of engineered cell or tissue implants is dependent on vascular regeneration to meet adequate metabolic requirements. However, development of a broadly applicable strategy for stable and functional vascularization has remained challenging. We report here highly organized and resilient microvascular meshes fabricated through a controllable anchored self-assembly method. The microvascular meshes are scalable to centimeters, almost free of defects and transferrable to diverse substrates, ready for transplantation. They promote formation of functional blood vessels, with a density as high as ~220 vessels mm-2, in the poorly vascularized subcutaneous space of SCID-Beige mice. We further demonstrate the feasibility of fabricating microvascular meshes from human induced pluripotent stem cell-derived endothelial cells, opening a way to engineer patient-specific microvasculature. As a proof-of-concept for type 1 diabetes treatment, we combine microvascular meshes and subcutaneously transplanted rat islets and achieve correction of chemically induced diabetes in SCID-Beige mice for 3 months.

9.
Wound Repair Regen ; 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31603580

RESUMO

Volumetric muscle loss (VML) is a segmental loss of skeletal muscle which commonly heals with fibrosis, minimal muscle regeneration, and loss of muscle strength. Treatment options for these wounds which promote functional recovery are currently lacking. This study was designed to investigate whether the collagen-GAG scaffold (CGS) promotes functional muscle recovery following VML. A total of 66 C57/Bl6 mice were used in a three-stage experiment. First, 24 animals were split into three groups which underwent sham injury or unilateral quadriceps VML injury with or without CGS implantation. Two weeks post-surgery, muscle was harvested for histological and gene expression analysis. In the second stage, 18 mice underwent bilateral quadriceps VML injury, followed by weekly functional testing using a treadmill. In the third stage, 24 mice underwent sham or bilateral quadriceps VML injury with or without CGS implantation, with tissue harvested six weeks post-surgery for histological and gene expression analysis. VML mice treated with CGS demonstrated increased remnant fiber hypertrophy versus both the VML with no CGS and uninjured groups. Both VML groups showed greater muscle fiber hypertrophy than non-injured muscle. This phenomenon was still evident in the longer-term experiment. The gene array indicated that the CGS promoted upregulation of factors involved in promoting wound healing and regeneration. In terms of functional improvement, the VML mice treated with CGS ran at higher maximum speeds than VML without CGS. A CGS was shown to enhance muscle hypertrophy in response to VML injury with a resultant improvement in functional performance. A gene array highlighted increased gene expression of multiple growth factors following CGS implantation. This suggests that implantation of a CGS could be a promising treatment for VML wounds. This article is protected by copyright. All rights reserved.

10.
J Neurosci ; 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31597725

RESUMO

Although several genes have been identified to promote axon regeneration in the central nervous system, our understanding of the molecular mechanisms by which mammalian axon regeneration is regulated is still limited and fragmented. Here by using female mouse sensory axon and optic nerve regeneration as model systems, we reveal an unexpected role of telomerase reverse transcriptase (TERT) in regulation of axon regeneration. We also provide evidence that TERT and p53 act downstream of c-Myc to control sensory axon regeneration. More importantly, overexpression of p53 in sensory neurons and retinal ganglion cells (RGCs) is sufficient to promote sensory axon and optic never regeneration, respectively. The study reveals a novel c-Myc-TERT-p53 signaling pathway, expanding horizons for novel approaches promoting CNS axon regeneration.Significance StatementDespite significant progress during the past decade, our understanding of the molecular mechanisms by which mammalian CNS axon regeneration is regulated is still fragmented. By using sensory axon and optic nerve regeneration as model systems, the study revealed an unexpected role of telomerase reverse transcriptase (TERT) in regulation of axon regeneration. The results also delineated a c-Myc-TERT-p53 pathway in controlling axon growth. Lastly, our results demonstrated that p53 alone was sufficient to promote sensory axon and optic nerve regeneration in vivo Collectively, the study not only revealed a new mechanisms underlying mammalian axon regeneration, but also expanded the pool of potential targets that can be manipulated to enhance CNS axon regeneration.

11.
Cell Prolif ; : e12670, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31568631

RESUMO

OBJECTIVES: To investigate the heterogeneous feature of actin filaments (ACFs) associated with the cellular membrane in HeLa and HCT-116 cells at the nanoscale level. MATERIALS AND METHODS: Fluorescence microscopy coupled with atomic force microscopy (AFM) was used to identify and characterize ACFs of cells. The distribution of ACFs was detected by Fluor-488-phalloidin-labelled actin. The morphology of the ACFs was probed by AFM images. The spatial correlation of the microvilli and ACFs was explored with different forces of AFM loading on cells. RESULTS: Intricate but ordered structures of the actin cytoskeletons associated with cellular membrane were characterized and revealed. Two different layers of ACFs with distinct structural organizations were directly observed in HCT-116 and HeLa cells. Bundle-shaped ACFs protruding the cellular membrane forming the microvilli, and the network ACFs underneath the cellular membrane were resolved with high resolution under near-physiological conditions. Approximately 14 nm lateral resolution was achieved when imaging single ACF beneath the cellular membrane. On the basis of the observed spatial distribution of the ultrastructure of the ACF organization, a model for this organization of ACFs was proposed. CONCLUSIONS: We revealed the two layers of the ACF organization in Hela and HCT-116 cells. The resolved heterogeneous structures at the nanoscale level provide a spatial view of the ACFs, which would contribute to the understanding of the essential biological functions of the actin cytoskeleton.

12.
Lancet Oncol ; 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31591062

RESUMO

BACKGROUND: Upper gastrointestinal cancers (including oesophageal cancer and gastric cancer) are the most common cancers worldwide. Artificial intelligence platforms using deep learning algorithms have made remarkable progress in medical imaging but their application in upper gastrointestinal cancers has been limited. We aimed to develop and validate the Gastrointestinal Artificial Intelligence Diagnostic System (GRAIDS) for the diagnosis of upper gastrointestinal cancers through analysis of imaging data from clinical endoscopies. METHODS: This multicentre, case-control, diagnostic study was done in six hospitals of different tiers (ie, municipal, provincial, and national) in China. The images of consecutive participants, aged 18 years or older, who had not had a previous endoscopy were retrieved from all participating hospitals. All patients with upper gastrointestinal cancer lesions (including oesophageal cancer and gastric cancer) that were histologically proven malignancies were eligible for this study. Only images with standard white light were deemed eligible. The images from Sun Yat-sen University Cancer Center were randomly assigned (8:1:1) to the training and intrinsic verification datasets for developing GRAIDS, and the internal validation dataset for evaluating the performance of GRAIDS. Its diagnostic performance was evaluated using an internal and prospective validation set from Sun Yat-sen University Cancer Center (a national hospital) and additional external validation sets from five primary care hospitals. The performance of GRAIDS was also compared with endoscopists with three degrees of expertise: expert, competent, and trainee. The diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of GRAIDS and endoscopists for the identification of cancerous lesions were evaluated by calculating the 95% CIs using the Clopper-Pearson method. FINDINGS: 1 036 496 endoscopy images from 84 424 individuals were used to develop and test GRAIDS. The diagnostic accuracy in identifying upper gastrointestinal cancers was 0·955 (95% CI 0·952-0·957) in the internal validation set, 0·927 (0·925-0·929) in the prospective set, and ranged from 0·915 (0·913-0·917) to 0·977 (0·977-0·978) in the five external validation sets. GRAIDS achieved diagnostic sensitivity similar to that of the expert endoscopist (0·942 [95% CI 0·924-0·957] vs 0·945 [0·927-0·959]; p=0·692) and superior sensitivity compared with competent (0·858 [0·832-0·880], p<0·0001) and trainee (0·722 [0·691-0·752], p<0·0001) endoscopists. The positive predictive value was 0·814 (95% CI 0·788-0·838) for GRAIDS, 0·932 (0·913-0·948) for the expert endoscopist, 0·974 (0·960-0·984) for the competent endoscopist, and 0·824 (0·795-0·850) for the trainee endoscopist. The negative predictive value was 0·978 (95% CI 0·971-0·984) for GRAIDS, 0·980 (0·974-0·985) for the expert endoscopist, 0·951 (0·942-0·959) for the competent endoscopist, and 0·904 (0·893-0·916) for the trainee endoscopist. INTERPRETATION: GRAIDS achieved high diagnostic accuracy in detecting upper gastrointestinal cancers, with sensitivity similar to that of expert endoscopists and was superior to that of non-expert endoscopists. This system could assist community-based hospitals in improving their effectiveness in upper gastrointestinal cancer diagnoses. FUNDING: The National Key R&D Program of China, the Natural Science Foundation of Guangdong Province, the Science and Technology Program of Guangdong, the Science and Technology Program of Guangzhou, and the Fundamental Research Funds for the Central Universities.

13.
Oncogene ; 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31591477

RESUMO

Bmi1 is overexpressed in one-third of hepatocellular carcinoma (HCC) patients and acts as an oncogene in hepatocarcinogenesis. However, the underlying mechanism is unclear. The role of TGFß signalling in HCC is not well defined as well. Here, we report that TGFß2 is a target of Bmi1 in HCC and has a tumour-suppressing role. In Bmi1-knockout mouse livers and HCC cell lines, TGFß2/SMAD cascade proteins were upregulated. TGFß2 expression was inversely correlated with Bmi1 expression in human and mouse HCC tissues. In vitro, Bmi1 knockdown activated TGFß2/SMAD signalling and led to cell apoptosis via upregulation of p15 and p21. TGFß2 inhibition rescued the inhibitory effect of Bmi1 knockdown on HCC cell survival, proliferation, and cell-cycle progression. In vivo, restoration of TGFß2 expression blocked Bmi1/Ras-driven hepatocarcinogenesis in mice. Chromatin immunoprecipitation and luciferase reporter assays revealed that Bmi1 repressed TGFß2 expression by binding to its promoter as a co-factor of polycomb repressor complex 1. Our findings elucidate the molecular mechanism underlying hepatic Bmi1-driven carcinogenesis and highlight the importance of TGFß2 as a tumour suppressor in HCC development.

14.
J Transl Med ; 17(1): 336, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31585531

RESUMO

BACKGROUND: To investigate the relationship between cyclin B1 (CCNB1) gene expression and cavernous sinus invasion in pituitary adenomas. METHODS: Twenty-four pituitary adenoma tissue samples were examined by RT-qPCR and Western blot to assess the mRNA expression levels and protein levels of CCNB1, E-cadherin and N-cadherin. Correlation analyses between the expression levels of E-cadherin, N-cadherin and CCNB1 were performed. After lentivirus-mediated knockdown of CCNB1 in rat pituitary adenoma cell lines (GH3 and GT1-1), cell function changes were studied. The relationship between CCNB1 and epithelial-mesenchymal transition (EMT) was further verified by animal experiments. RESULTS: CCNB1 and N-cadherin gene expression were significantly higher in the invasive pituitary adenomas than in the non-invasive pituitary adenomas. Conversely, E-cadherin expression in the invasive pituitary adenomas was significantly lower. CCNB1 gene expression was downregulated in the GH3 and GT1-1 pituitary adenoma cell lines; N-cadherin expression was also decreased, but E-cadherin expression was increased. These results were confirmed in vivo. After downregulation of CCNB1, cell invasion and migration was significantly reduced in Transwell experiments. CONCLUSION: High CCNB1 expression in pituitary adenoma affects cavernous sinus invasion through EMT.

15.
Acta Neurobiol Exp (Wars) ; 79(3): 302-308, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31587022

RESUMO

Preclinical studies have suggested that increased adult neurogenesis in the hippocampus might have potential therapeutic effects for Alzheimer's disease and depression; therefore, it is a target for the treatment of some brain diseases. In this technical communication, we propose a cell-based fluorescence assay to study the neurogenesis of adult hippocampal progenitor cells that can be used for high-throughput screening of drugs promoting neurogenesis. Three fluorescent dyes (DAPI, Alexa Fluor 488, and Alexa Fluor 594) and a fluorescence spectrophotometry reader were used, which confirmed that the mutual interference of the three fluorescent dyes is very low. We used this cell-based fluorescence assay to evaluate the effects of three neurotrophic factors, ciliary neurotrophic factor (CNTF), insulin-like growth factor 1 (IGF-1), and IGF-2 on the promotion of neurogenesis in adult hippocampal neural progenitor cells. The fluorescence intensity ratio of the neuronal marker, class III ß-tubulin, to the housekeeping protein, glyceraldehyde 3-phosphate dehydrogenase, or nuclear staining dye, DAPI, in CNTF-treated cells was significantly higher than in control cells. The ratios in IGF-1 and IGF-2-treated cells were slightly higher under higher cell density conditions. These results are consistent with those in previous reports; therefore, this report proved the efficacy of this method. Taken together, the results showed that this simple, rapid, and economical cell-based immunofluorescence assay could be a powerful tool for the rapid screening of drugs that promote adult neurogenesis.

16.
Org Lett ; 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31588751

RESUMO

C═C bond breaking to access the C═N bond remains an underdeveloped area. A new protocol for C═C bond cleavage of alkenes under nonoxidative conditions to produce imines via an iron-catalyzed nitrene transfer reaction of 4-hydroxystilbenes with aryl azides is reported. The success of various sequential one-pot reactions reveals that the good compatibility of this method makes it very attractive for synthetic applications. On the basis of experimental observations, a plausible reaction mechanism is also proposed.

17.
Org Biomol Chem ; 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31588947

RESUMO

An efficient and convenient synthesis of diversely substituted naphtho[1',2':4,5]imidazo[1,2-a]-pyridine derivatives from the cascade reactions of 2-arylimidazo[1,2-a]pyridines with a-diazo carbonyl compounds via Rh(iii)-catalyzed regioselective C(sp2)-H alkylation followed by intramolecular annulation is presented. Interestingly, when simple 2-arylimidazo[1,2-a]pyridines were used as the substrates, 5,6-disubstituted naphtho[1',2':4,5]imidazo[1,2-a]pyridines were efficiently obtained, whereas using 2-arylimidazo[1,2-a]pyridine-3-carbaldehydes as the substrates afforded naphtho[1',2':4,5]imidazo[1,2-a]-pyridine-5-carboxylates as the dominating products. Compared with literature methods for the synthesis of naphtho[1',2':4,5]imidazo[1,2-a]pyridine derivatives, the protocol presented herein has advantages such as easily obtainable substrates, simple operational procedure, high efficiency and excellent regio- and chemoselectivity.

18.
Plant Sci ; 287: 110169, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31481230

RESUMO

During the grain filling stage, high light (HL) usually results in premature leaf senescence and significant yield loss in wheat. To explore the responses of sugar metabolism and the association of sugar accumulation and leaf senescence in HL, the activity and gene expression of sugar metabolism-related enzymes were analyzed when two wheat cultivars Triticum aestivum L. Xiaoyan 54 (XY54, HL tolerant) and Jing 411 (J411, HL sensitive) were transferred from low light (LL) to HL for 28 d. The results showed that the CO2 assimilation rate, quantity of Rubisco and chlorophyll binding proteins decreased substantially for both cultivars in HL. However, the content of fructose, sucrose, and starch increased dramatically. In addition, the activity of hexokinase, pyruvate kinase, sucrose phosphate synthase, sucrose synthase, and alkaline/neutral invertase increased significantly while the expression of most of the sugar metabolism-related genes were repressed by long-term HL. Correlation analysis revealed that sugar content and sucrose phosphate synthase activity were negatively while the expression of most sugar metabolism-related genes were positively correlated with chlorophyll content during HL treatment. Comparatively, the HL tolerant cultivar XY54 accumulated less sugars than the HL sensitive cultivar J411, suggesting that sugar metabolism may be the regulation target for wheat improvement to cope with HL stress.

19.
Autoimmunity ; : 1-7, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31476899

RESUMO

Immunodeficiency, centromeric instability and facial anomalies syndrome (ICF) is a rare autosomal recessive disorder, which is characteristic of a severe impairment of immunity. In the genetic aspect, ICF is featured with mutations primarily located in the specific genes (DNMT3B for ICF1, ZBTB24 for ICF2, CDCA7 for ICF3, and HELLS for ICF4). The subtelomeric region is defined as 500 kb at the terminal of each autosomal arm. And subtelomeric DNA fragments can partially regulate key biological activities, including chromosome movement and localization in the nucleus. In this review, we updated and summarized gene mutations in ICF based on the previous review. In addition, we focused on the correlation between subtelomeric DNA methylation and ICF. The relationship between subtelomeric methylation and telomere length in ICF was also summarized.

20.
Neuroreport ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31503210

RESUMO

OBJECTIVES: The aim of this study was to determine the expression level of immunoproteasome and its clinical significance in glioma preliminarily. Furthermore, we studied the function and molecular mechanism of proteasome inhibitor ONX 0912 on glioma cell. MATERIALS AND METHODS: The expression of immunoproteasome in glioma and tumor-adjacent brain tissues was detected by western blot. Immunohistochemical technique was used to detect the expression of low-molecular-mass polypeptide 7 in 55 cases of glioma tissues and 6 cases of tumor-adjacent brain tissues. Chi-square test was used to analyze the relationship between the expression level of low-molecular-mass polypeptide 7 and clinical characteristics. Kaplan-Meier method and Cox regression analysis were applied to analyze the correlation between low-molecular-mass polypeptide 7 expression and prognosis of patients. 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2Htetrazolium) (MTS) proliferation assay was introduced to detect the impact of ONX 0912 on proliferation of glioma cells. Western blot was used to detect the apoptosis- and autophagy-related protein in glioma cell treated with ONX 0912. RESULTS: Our results showed that only low-molecular-mass polypeptide 7 expression was notably upregulated in gliomas in comparison with tumor-adjacent brain tissues and further increased in malignant gliomas compared with benign gliomas (P < 0.01). In the multivariate Cox proportional regression analyses, it was evident that low-molecular-mass polypeptide 7 was an independent unfavorable prognostic factor (P < 0.05). The results of MTS assay showed that ONX 0912 could inhibit the proliferation of glioma cell. Besides, we found that ONX 0912 could prompt apoptosis and autophagosome accumulation, which may be responsible for inhibiting glioma cell proliferation. CONCLUSION: In conclusion, our results indicated that low-molecular-mass polypeptide 7 might be a candidate prognostic biomarker, and proteasome inhibitor ONX 0912 might act as a potential treatment agent for glioma.

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