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1.
Chem Commun (Camb) ; 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32373821

RESUMO

An unprecedented indium-promoted three-component 1,3,4-trifunctionalization cascade of 1,3-enynes with sodium sulfinates and tert-butyl nitrite (TBN) to access 5-sulfonylisoxazoles via [3+2] annulation is reported. By employing TBN as both the radical initiator and the N-O two atom unit, this method enables the formation of three new carbon-heteroatom bonds, C-S, C-N and C-O bonds, in a single reaction through a sequence of sulfonylation, isomerization, nitration and annulation with a broad substrate scope, excellent selectivity and the potential of late-stage functionalization of natural products.

2.
J Vis Exp ; (158)2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32391814

RESUMO

The Drosophila model has been invaluable for the study of neurological function and for understanding the molecular and cellular mechanisms that underlie neurodegeneration. While fly techniques for the manipulation and study of neuronal subsets have grown increasingly sophisticated, the richness of the resultant behavioral phenotypes has not been captured at a similar detail. To be able to study subtle fly leg movements for comparison amongst mutants requires the ability to automatically measure and quantify high-speed and rapid leg movements. Hence, we developed a machine-learning algorithm for automated leg claw tracking in freely walking flies, Feature Learning-based Limb segmentation and Tracking (FLLIT). Unlike most deep learning methods, FLLIT is fully automated and generates its own training sets without a need for user annotation, using morphological parameters built into the learning algorithm. This article describes an in depth protocol for carrying out gait analysis using FLLIT. It details the procedures for camera setup, arena construction, video recording, leg segmentation and leg claw tracking. It also gives an overview of the data produced by FLLIT, which includes raw tracked body and leg positions in every video frame, 20 gait parameters, 5 plots and a tracked video. To demonstrate the use of FLLIT, we quantify relevant diseased gait parameters in a fly model of Spinocerebellar ataxia 3.

3.
Glob Chang Biol ; 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32400947

RESUMO

Warming can accelerate the decomposition of soil organic matter and stimulate the release of soil greenhouse gases (GHGs), but to what extent soil release of methane (CH4 ) and nitrous oxide (N2 O) may contribute to soil C loss for driving climate change under warming remains unresolved. By synthesizing 1,845 measurements from 164 peer-reviewed publications, we show that around 1.5°C (1.16-2.01°C) of experimental warming significantly stimulates soil respiration by 12.9%, N2 O emissions by 35.2%, CH4 emissions by 23.4% from rice paddies, and by 37.5% from natural wetlands. Rising temperature increases CH4 uptake of upland soils by 13.8%. Warming-enhanced emission of soil CH4 and N2 O corresponds to an overall source strength of 1.19, 1.84, and 3.12 Pg CO2 -equivalent/year under 1°C, 1.5°C, and 2°C warming scenarios, respectively, interacting with soil C loss of 1.60 Pg CO2 /year in terms of contribution to climate change. The warming-induced rise in soil CH4 and N2 O emissions (1.84 Pg CO2 -equivalent/year) could reduce mitigation potential of terrestrial net ecosystem production by 8.3% (NEP, 22.25 Pg CO2 /year) under warming. Soil respiration and CH4 release are intensified following the mean warming threshold of 1.5°C scenario, as compared to soil CH4 uptake and N2 O release with a reduced and less positive response, respectively. Soil C loss increases to a larger extent under soil warming than under canopy air warming. Warming-raised emission of soil GHG increases with the intensity of temperature rise but decreases with the extension of experimental duration. This synthesis takes the lead to quantify the ecosystem C and N cycling in response to warming and advances our capacity to predict terrestrial feedback to climate change under projected warming scenarios.

4.
Clin Cardiol ; 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32352584

RESUMO

BACKGROUND: Elevated body mass index (BMI) is related with reduced mortality in various cardiovascular diseases. HYPOTHESIS: Gender-specific association between BMI and mortality exists in atrial fibrillation (AF). METHODS: In this multicenter observational study with a mean follow-up of 1 year, a total of 1991 AF patients were enrolled and divided into two groups based on the gender. The primary endpoint was all-cause mortality while the secondary endpoints were defined as cardiovascular mortality, stroke, and major adverse events during 1-year follow-up. Cox regression was performed to identify the association between BMI and clinical outcomes according to gender. RESULTS: Female patients with AF tended to be older (P = .027) and thinner (P < .001) than male patients with AF. They were more likely to have heart failure, hyperthyroidism, and valvular AF (all P < .05), but less likely to have coronary artery disease and prior myocardial infarction (all P < .01). Multivariate analysis revealed that overweight (HR(95%CI): 0.55(0.41-0.75), P < .001) and obese patients (HR(95%CI): 0.56(0.34-0.94), P = .028) were associated with significant lower all-cause mortality compared with normal weight patients for the entire cohort. Similar association between elevated BMI and reduced all-cause mortality were only identified in female patients with AF (overweight vs normal weight: HR(95%CI): 0.43(0.27-0.70); obesity vs normal weight: HR(95%CI): 0.46(0.22-0.97)), but not in male patients with AF. CONCLUSION: This study indicates that overweight and obesity were related with improved survival in patients with AF. The association between elevated BMI and reduced mortality was dependent on gender, which was only significant in female patients, rather than male patients.

5.
J Agric Food Chem ; 68(19): 5437-5447, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32320610

RESUMO

The purpose of this work was to conjugate phosvitin (Pv) with gallic acid (GA) to explore a new emulsifier that had both good emulsifying properties and antioxidant activity. The Pv-GA complex was prepared at a GA concentration of 1.5 mg/mL with pH 9.0. The Pv-GA complex obtained was identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and characterized with infrared, ultraviolet, and fluorescence spectra. The emulsifying activity and stability of the Pv-GA complex were slightly improved, and antioxidant activities was significantly enhanced. Furthermore, the Pv-GA complex was used to load conjugated linoleic acid (CLA) for microemulsion preparation. Results showed that the Pv-GA complex could increase the viscosity and lipid antioxidant capacity of Pv-GA/CLA microemulsion. The Pv-GA/CLA microemulsion had remarkable emulsifying activity, emulsifying stability, pH, and thermal stability and poor salt stability.

6.
J Tradit Chin Med ; 40(1): 112-120, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32227772

RESUMO

OBJECTIVE: To evaluate the effectiveness of traditional Chinese herbal Xinglouchengqi (XLCQ) decoction for the treatment of constipation in acute ischemic stroke patients, and figure out the role that bowel movements play in the treatment of acute ischemic stroke. METHODS: A total of 317 eligible patients were recruited and randomized to the XLCQ group (211 patients) or the control group (106 patients). In addition to conventional standard medical care and rehabilitation, participants in the XLCQ group received XLCQ decoction, while the control group received clysis therapy using glycerin enemas or lactulose oral solution. Both groups were given treatment for 3 to 6 d, during which they received daily visits to record defecation features and accompanying symptoms. Neurological assessments using the National Institutes of Health Stroke Scale (NIHSS) were conducted before and 1 month after treatment. RESULTS: Patients in the XLCQ group had lower aggregate constipation scores compared with the control group on days 3 and 5 (P < 0.05). Spontaneous bowel movements tended to reappear more rapidly after taking the XLCQ decoction than after conventional laxative treatment. Both the average aggregate constipation score and the time taken to achieve spontaneous bowel movements showed positive correlations with NIHSS scores before and 1 month after treatment (P < 0.01). CONCLUSION: Treatment with XLCQ decoction effectively alleviated the overall symptoms of constipation in acute ischemic stroke patients. The status of bowel movements in acute ischemic stroke can reflect the severity of neurological impairment and predict neurological outcomes at 1 month.

7.
Insect Sci ; 2020 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-32112590

RESUMO

Workers of Apis cerana cerana undergo an in-hive nursing to outdoor foraging transition, but the genes underlying this aged-related transition remain largely unknown. Here, we sequenced the head transcriptomes of its 7-day-old normal nurses, 18- and 22-day-old normal foragers, 7-day-old precocious foragers and 22-day-old over-aged nurses to unravel the genes associated with this transition. Mapping of the sequence reads to Apis mellifera genome showed that the 3 types of foragers had a greater percentage of reads from annotated exons and intergenic regions, whereas the 2 types of nurses had a greater percentage of reads from introns. Pair- and group-wise comparisons of the 5 transcriptomes revealed 59 uniquely expressed genes (18 in nurse and 41 in forager) and 14 nurse- and 15 forager-upregulated genes. The uniquely expressed genes are usually low-abundance lncRNAs, transcription factors, transcription coactivators, RNA-binding proteins, kinases or phosphatases that are involved in signaling and/or regulation, whereas the nurse- or forager-upregulated genes are often high-abundance downstream genes that directly perform the tasks of nurses or foragers. Taken together, these results suggest that the nurse-forager transition is coordinated by a social signal-triggered epigenetic shift from introns to exons/intergenic regions and the resulted transcriptional shift between the nurse- and forager-associated genes. This article is protected by copyright. All rights reserved.

8.
Cell Prolif ; 53(4): e12782, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32196806

RESUMO

OBJECTIVES: Extraembryonic endoderm (XEN) cells are isolated from primitive endoderm (PrE) of blastocysts. Just like PrE, XEN cells have the ability to differentiate into parietal endoderm (PE) and visceral endoderm (VE), and therefore, they are useful tools for studying mechanisms of PrE cells development and differentiation. Pig is an ideal model for studying human cardiovascular and metabolic diseases and a potential organ source for allotransplantation, while no XEN cell has been obtained from porcine embryos. MATERIALS AND METHODS: Using a serum-free culture system, we directly derived porcine extraembryonic endoderm-like cells (pXEN-like cells) from day 6-7 blastocysts, which could maintain self-renewal for at least 30 passages. RESULTS: The pXEN-like cells resembled mouse XEN cells with large and flat clone morphology and expressed XEN marker genes but not pluripotent genes. Upon in vitro induction, the cells could differentiate into VE and PE. FGF/MEK signalling was not only essential for the maintenance of pXEN-like cells, but also the induction of pXEN-like cells from porcine embryonic stem (pES) cells. CONCLUSIONS: We directly obtained cell lines with XEN characteristics from porcine embryos for the first time. The cells will be helpful tools for studying embryonic development and cell differentiation, which also represent promising cell sources for human regenerative medicine.


Assuntos
Blastocisto/citologia , Células-Tronco Embrionárias/citologia , Endoderma/citologia , Animais , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Autorrenovação Celular , Separação Celular/métodos , Células Cultivadas , Feminino , Suínos
9.
Int J Mol Med ; 45(4): 1103-1111, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32124942

RESUMO

A pterygium is an inflammatory, invasive and proliferative lesion on the ocular surface, which can decrease visual acuity, damage the ocular surface and affect the appearance of the eye. However, the underlying molecular mechanisms of the pathogenesis remain unclear. In the present study, the role of apoptosis­associated protein Livin in the occurrence and development of pterygium was investigated. Primary samples from quiescent or advanced clinical stages of pterygium and normal human conjunctival tissues were used to assess mRNA and protein expression levels of Livin using reverse transcription­quantitative PCR and immunohistochemistry, respectively. Livin was knocked down in pterygium epithelial cells (PECs) using small interfering RNA (siRNA), to investigate the role of Livin in PEC viability, migration, invasion ability and apoptosis. The cell viability, invasion ability and apoptosis of PECs following ultraviolet B (UVB) radiation alone or in combination with Livin silencing were also analyzed. Expression levels of Livin increased in the pterygium tissues compared with those in the normal conjunctiva at both the mRNA and protein levels. Livin expression levels in advanced pterygium were significantly higher compared with those in quiescent pterygium samples. Knockdown of Livin expression levels significantly reduced cell migration, invasion ability and cell viability, and induced apoptosis of PECs. Inhibition of Livin expression in PECs increased the expression levels of caspase­7, caspase­3 and E­cadherin, whereas expression levels of Snail were downregulated. Cell viability and invasion ability in PECs was enhanced following UVB radiation and Livin expression upregulated. UVB irradiation induced cell invasion ability of PECs and this was attenuated by Livin­silencing. Transfection with Livin siRNA also partially recovered the apoptosis rate of PECs, which was reduced by UVB irradiation. In conclusion, Livin was upregulated in pterygium, and UVB radiation functions in the development of pterygium by inducing Livin expression.

10.
Sci Total Environ ; 713: 136631, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32019019

RESUMO

Stable isotopes of oxygen (δ18O) and hydrogen (δD) in precipitation can be used as dual conservative tracers in the hydrologic cycle and help to understand hydrological and atmospheric processes. Although long-term monthly precipitation global isotope datasets are available in some locations, currently there are limited daily precipitation isotope data, particularly in the Midwest region of the USA. In this study we report a daily precipitation δ18O and δD dataset from March 2014-December 2017 in Dayton, Ohio, the USA. The daily δ18O and δD vary from -28.0 to 0.4‰, and -214.0 to 9.0‰ respectively. The data exhibit strong seasonality with lower δ18O and δD values in the winter and higher values in the summer. The precipitation isotopic values are mainly controlled by temperature, and show no correlation with precipitation amount and relative humidity. However, δ18O-temperature relationship varies among different seasons. The correlation is the strongest in winter (R2 = 0.56), weaker in spring (R2 = 0.28) and fall (R2 = 0.24), and almost non-existent in summer (R2 = 0.1). The slope values also vary with highest value in winter (0.68‰/OC) and much smaller in other seasons. The HYSPLIT back trajectory analyses show that Pacific, Gulf of Mexico, Arctic and Continental moistures are the main sources for southwestern Ohio with different seasonal contributions. The isotopic compositions of precipitation from different sources show small intra-season variations but large seasonal variability. Our daily-resolved dataset provides new insights into the main controls on the isotopic composition of precipitation and its seasonal variations, which could help to understand atmospheric processes and enable their proper use in interpretation of paleoclimate proxies, particularly those with seasonal bias.

11.
Artigo em Inglês | MEDLINE | ID: mdl-32106656

RESUMO

Objective: This study was aimed to investigate the muscle-specific beef color stability at normal and high ultimate pHs. Methods: The impact of muscle ((longissimus lumborum; LL) vs. psoas major (PM)) and pH ((normal ultimate pH; Np) vs. high pH dark cutting beef (DC)) on color stability, indicated by basic color traits, metmyoglobin reducing activity and oxygen consumption (OC), as well as the lipid oxidation, were determined over 7 days of display at 4 °C. Results: DC-LL had the highest pH (6.92), followed by DC-PM (6.01), Np-PM (5.76) and Np-LL (5.52). DC-LL had increased (P < 0.05) a*, chroma and % OMb during display. DC-LL also had the highest metmyoglobin reducing activity and OC among all the samples, thus, the greatest color stability, although very dark throughout storage, with lowest values for lightness (L*) and yellowness (b*). Np-LL also exhibited relatively high color stability, as a result of its lower % MMb and OC and higher MRA than psoas muscle samples. The 0.2 unit difference of the pH between DC and Np psoas muscle, resulted in the difference of the color intensity, not the color stability. Interestingly, high pH psoas muscle (DC-PM) did not have better color stability than Np-PM, and in fact had lower color stability than even Np-LL. The similar level of OC and lipid oxidation cannot explain the difference in color stability between DC-PM and Np-LL. Conclusion: Dark cutting beef does not always show better color stability compared with normal pH beef, which depends on the muscle type. The balance of MRA and OC is important to keep the color in great intensity and stability in the meantime.

12.
Plant J ; 102(3): 431-447, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32027440

RESUMO

Root endodermis, the innermost cortical layer surrounding the root vasculature, serves as the foremost barrier to water, solutes, and nutrients taken up from soil. Endodermis barrier functionality is achieved via its hydrophobic coating of lignified Casparian strips and the suberin lamellae; nonetheless the regulatory mechanisms underlying endodermis suberization are still elusive. Here, we discovered that the Arabidopsis SUBERMAN (SUB) transcription factor controls the establishment of the root suberin lamellae. Transient expression of SUB in Nicotiana benthamiana leaves resulted in the induction of heterologous suberin genes, the accumulation of suberin-type monomers, and consequent deposition of suberin-like lamellae. We demonstrate that SUB exerts its regulatory roles by transactivating promoters of suberin genes. In Arabidopsis, SUB is expressed in patchy and continuous suberization root endodermal cells, and thus roots with higher or lower expression of SUB display altered suberin polymer deposition patterns and modified composition. While these changes did not interfere with Casparian strip formation they had a substantial effect on root uptake capacity, resulting in varied root and leaf ionomic phenotypes. Gene expression profiling revealed that SUB function impacts transcriptional networks associated with suberin, phenylpropanoids, lignin, and cuticular lipid biosynthesis, as well as root transport activities, hormone signalling, and cell wall modification. Our findings highlight SUB as a regulator of root endodermis suberization during normal development, and its characterization is thus a key step towards dissecting the molecular mechanisms partaking in root endodermal barrier functionalities.

13.
J Affect Disord ; 266: 671-677, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32056943

RESUMO

BACKGROUND: Some studies have shown that long-term exposure to job stress could result in burnout, and BDNF polymorphism may play an important role in its psychopathological mechanism. However, the inter-relationships between the job-related stress, serum BDNF level, BDNF genotype and job burnout have not been examined. This study was to explore the job stress × BDNF rs2049046 interaction and the role of serum BDNF level in job burnout in a Chinese Han population. METHODS: Using a cross-sectional design, 205 healthy subjects were recruited from a public institution in Beijing and assessed for job stress using the House and Rizzo's Work Stress Scale, and job burnout using the Maslach Burnout Inventory (MBI). The BDNF rs2049046 polymorphism was genotyped and serum BDNF (sBDNF) levels were assayed in all of subjects. RESULTS: The correlations between the job stress score and two burnout subscale scores (emotional exhaustion and cynicism) were significant (both p < 0.001), but not with professional efficacy. There were no significant main effects of the BDNF rs2049046 genotype on burnout, and no significant correlation was observed between sBDNF levels and job burnout. However, the interaction between the job stress and the BDNF rs2049046 genotype (F = 2.709, df = 2, 183, p = 0.032) or between the job stress and sBDNF levels on burnout was significant (t = -2.132, p = 0.035). To be specific, the individuals with the BDNF rs2049046 AT genotype showed a greater susceptibility to the burnout cynicism compared to AA homozygote only in medium-stress group (F = 4.327, df = 1,117, p = 0.015). The individuals who had lower sBDNF showed higher burnout level than those who had higher sBDNF in low-stress group. CONCLUSIONS: Our findings suggest that the BDNF system may interact with job stress to affect burnout, showing that interaction between BDNF rs2049046 and job stress or the interaction between BDNF levels with work stress on certain burnout dimensions.

14.
J Cell Physiol ; 235(7-8): 5811-5822, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32003013

RESUMO

Although we have obtained porcine pluripotent stem cell lines (pPSCs) from blastocysts, the cells exhibit flat clonal morphology and do not support single-cell passage. There is massive cell death after cell dissociation, and the efficiency of single-cell colony is generally ≤10%. In a recent study, we got a new pPSCs using two Wnt signaling pathway regulators CHIR99021 and XAV939. This cell had strong biological viability, small-domed morphology, and its cloning efficiency after dissociation was 80-90%. The CH/XAV-treated cells expressed elevated levels of pluripotent genes, and possessed differentiation abilities both in vitro and in vivo, proven by the formation of embryonic bodies and teratomas with three germ layers. Furthermore, we found that the combinative use of CHIR99021 and XAV939 resulted in ß-catenin-maintained expression in the cytoplasm but not translocation to the nuclei for WNT/TCF activation. In the meanwhile, E-cadherin located on the cell membrane, thereby activated the PI3K/Akt signaling pathway to enhance the pluripotency of the cells. Our study obtained new pPSCs, which were even closer to the naïve state with only two small molecule inhibitors, and the improved pluripotency of pPSCs could facilitate transgenic manipulation and regenerative medicine research. Besides, our study casted a light on the understanding of pPSCs and the derivation of authentic porcine embryonic stem cells.

15.
Neural Netw ; 125: 70-82, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32070857

RESUMO

Deep neural network (DNN) quantization converting floating-point (FP) data in the network to integers (INT) is an effective way to shrink the model size for memory saving and simplify the operations for compute acceleration. Recently, researches on DNN quantization develop from inference to training, laying a foundation for the online training on accelerators. However, existing schemes leaving batch normalization (BN) untouched during training are mostly incomplete quantization that still adopts high precision FP in some parts of the data paths. Currently, there is no solution that can use only low bit-width INT data during the whole training process of large-scale DNNs with acceptable accuracy. In this work, through decomposing all the computation steps in DNNs and fusing three special quantization functions to satisfy the different precision requirements, we propose a unified complete quantization framework termed as "WAGEUBN" to quantize DNNs involving all data paths including W (Weights), A (Activation), G (Gradient), E (Error), U (Update), and BN. Moreover, the Momentum optimizer is also quantized to realize a completely quantized framework. Experiments on ResNet18/34/50 models demonstrate that WAGEUBN can achieve competitive accuracy on the ImageNet dataset. For the first time, the study of quantization in large-scale DNNs is advanced to the full 8-bit INT level. In this way, all the operations in the training and inference can be bit-wise operations, pushing towards faster processing speed, decreased memory cost, and higher energy efficiency. Our throughout quantization framework has great potential for future efficient portable devices with online learning ability.

16.
Meat Sci ; 163: 108046, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31954335

RESUMO

Label-free proteomics was applied to understand the color and color stability development of dark cutting beef (DC). The color traits of DC (pH = 6.86) and normal beef (pH = 5.49) were determined during 7 days of display. DC had a lower redness and greater color stability, which was attributed to its higher deoxy-myoglobin content, greater oxygen consumption, as well as higher metmyoglobin reducing activity and lower lipid oxidation. A total of 28 differentially expressed mitochondrial proteins (fold change >1.8) between the two groups were identified, with 21 proteins overexpressed in DC mainly involved in oxidative phosphorylation, generation of reducing equivalent, TCA cycle and chaperones. These enhance the level of mitochondrial respiration, the stability of reducing MetMb and myoglobin and mitochondria function, leading to color characteristics of DC. Moreover, Glutaryl-CoA dehydrogenase was for the first time reported to be significantly associated with color parameters and its direct relationship with meat color is worthy investigation.

17.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 34(1): 109-115, 2020 Jan 15.
Artigo em Chinês | MEDLINE | ID: mdl-31939245

RESUMO

Objective: To separate peripheral blood mesenchymal stem cells (PBMSC) and peripheral blood endothelial progenitor cells (PBEPC) from peripheral blood, and investigate the biological characteristics of composite cell sheets of PBMSC and PBEPC. Methods: The peripheral blood of healthy adult New Zealand white rabbits was extracted and PBMSC and PBEPC were separated by density gradient centrifugation. Morphological observation and identification of PBMSC and PBEPC were performed. The 3rd generation of PBMSC and PBEPC were used to construct a composite cell sheet at a ratio of 1∶1, and the 3rd generation of PBMSC was used to construct a single cell sheet as control. The distributions of cells in two kinds of cell sheets were observed by HE staining. In addition, the expression of alkaline phosphatase (ALP), osteocalcin (OCN), and vascular endothelial growth factor (VEGF) in the supernatants of cell sheets were observed by ELISA at 1, 5, and 10 days after osteogenic induction. Results: The morphology of PBMSC was spindle-shaped or polygonal, and PBMSC had good abilities of osteogenic and adipogenic differentiation. The morphology of PBEPC was paved stone-like, and the tube-forming test of PBEPC was positive. Two kinds of cell sheets were white translucent. The results of HE staining showed that the composite cell sheet had more cell layers and higher cell density than the single cell sheet. The expressions of ALP, OCN, and VEGF in the supernatant of the two groups of cell sheets increased with the time of induction. The expression of OCN in the group of composite cell sheet was significantly higher than that in the group of single cell sheet on the 5th and 10th day, ALP on the 10th day was significantly higher than that in the group of single cell sheet, VEGF expression on the 1st, 5th, and 10th day was significantly higher than that in the group of single cell sheet, all showing significant differences ( P<0.05), and there was no significant difference between the two groups at other time points ( P>0.05). Conclusion: PBMSC have stable differentiation ability, and they have good application prospects because of their minimally invasive access. Composite cell membranes constructed by co-culture of two kinds of cells and induction of membrane formation provides a new idea and exploration for tissue defect repair.


Assuntos
Células Progenitoras Endoteliais , Células-Tronco Mesenquimais , Animais , Diferenciação Celular , Células Cultivadas , Osteogênese , Coelhos , Engenharia Tecidual , Fator A de Crescimento do Endotélio Vascular
18.
J Exp Bot ; 71(9): 2817-2827, 2020 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31990035

RESUMO

Geminiviruses are DNA viruses that cause severe diseases in diverse species of plants, resulting in considerable agricultural losses worldwide. C4 proteins are a major symptom determinant in several geminiviruses, including Beet severe curly top virus (BSCTV). Here, we uncovered a novel mechanism by which danger peptide signaling enhances the internalization of BSCTV C4 in plant cells. Previous studies showed that this signaling is important for activation of bacterium- and fungus-triggered immune responses, but its function in plant-virus interactions was previously unknown. Pep1 RECEPTOR1 (PEPR1) and PEPR2 are receptor kinases recognized by Peps (plant elicitor peptides) in the danger peptide pathway. We found that BSCTV C4 up-regulated and interacted with PEPR2 but not PEPR1. The Pep1-PEPR2 complex stimulated the internalization of C4 in both Arabidopsis and Nicotiana benthamiana cells. Furthermore, C4 induced callus formation in Arabidopsis, which was suppressed by PEPR2 overexpression but enhanced in the pepr2 mutants. In the presence of Pep1, overexpression of PEPR2 suppressed BSCTV infection in N. benthamiana. Exogenous Pep1 also reduced BSCTV infection in Arabidopsis in a PEPR2-dependent manner. Thus, PEPR2 recognizes the symptom determinant C4 and enhances its internalization mediated by danger peptides, suppressing BSCTV infection.

19.
J Exp Bot ; 71(6): 1815-1827, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31990970

RESUMO

The transcription factor Woolly (Wo) and its downstream gene CycB2 have been shown to regulate trichome development in tomato (Solanum lycopersicum). It has been demonstrated that only the gain-of-function allele of Slwo (SlWoV, the Slwo woolly motif mutant allele) can increase the trichome density; however, it remains unclear why the two alleles function differently in trichome development. In this study, we used Nicotiana benthamiana as a model and cloned the homologues of Slwo and SlCycB2 (named Nbwo and NbCycB2). We also constructed a Nbwo gain-of-function allele with the same mutation site as SlWoV (named NbWoV). We found that both Nbwo and NbWoV directly regulate NbCycB2 and their own expression by binding to the promoter of NbCycB2 and their own genomic sequences. As form of a feedback regulation, NbCycB2 negatively regulates trichome formation by repressing Nbwo activity at the protein level. We also found that mutations in the Nbwo woolly motif can prevent repression of NbWoV by NbCycB2, which results in a significant increase in the amount of active Nbwo proteins and in increases in trichome density and the number of branches. Our results reveal a novel reciprocal regulation mechanism between NbCycB2 and Nbwo during trichome formation in N. benthamiana.

20.
J Cell Mol Med ; 24(5): 2761-2771, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31970850

RESUMO

Lung immune responses to respiratory pathogens and allergens are initiated in early life which will further influence the later onset of asthma. The airway epithelia form the first mechanical physical barrier to allergic stimuli and environmental pollutants, which is also the key regulator in the initiation and development of lung immune response. However, the epithelial regulation mechanisms of early-life lung immune responses are far from clear. Our previous study found that integrin ß4 (ITGB4) is decreased in the airway epithelium of asthma patients with specific variant site. ITGB4 deficiency in adult mice aggravated the lung Th2 immune responses and enhanced airway hyper-responsiveness (AHR) with a house dust mite (HDM)-induced asthma model. However, the contribution of ITGB4 to the postnatal lung immune response is still obscure. Here, we further demonstrated that ITGB4 deficiency following birth mediates spontaneous lung inflammation with ILC2 activation and increased infiltration of eosinophils and lymphocytes. Moreover, ITGB4 deficiency regulated thymic stromal lymphopoietin (TSLP) production in airway epithelial cells through EGFR pathways. Neutralization of TSLP inhibited the spontaneous inflammation significantly in ITGB4-deficient mice. Furthermore, we also found that ITGB4 deficiency led to exaggerated lung allergic inflammation response to HDM stress. In all, these findings indicate that ITGB4 deficiency in early life causes spontaneous lung inflammation and induces exaggerated lung inflammation response to HDM aeroallergen.

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