Study of the cytological features of bone marrow mesenchymal stem cells from patients with neuromyelitis optica.

Neuromyelitis optica (NMO) is a refractory autoimmune inflammatory disease of the central nervous system without an effective cure. Autologous bone marrow‑derived mesenchymal stem cells (BM‑MSCs) are considered to be promising therapeutic agents for this disease due to their potential regenerative, immune regulatory and neurotrophic effects. However, little is known about the cytological features of BM‑MSCs from patients with NMO, which may influence any therapeutic effects. The present study aimed to compare the proliferation, differentiation and senescence of BM‑MSCs from patients with NMO with that of age‑ and sex‑matched healthy subjects. It was revealed that there were no significant differences in terms of cell morphology or differentiation capacities in the BM‑MSCs from the patients with NMO. However, in comparison with healthy controls, BM‑MSCs derived from the Patients with NMO exhibited a decreased proliferation rate, in addition to a decreased expression of several cell cycle‑promoting and proliferation‑associated genes. Furthermore, the cell death rate increased in BM‑MSCs from patients under normal culture conditions and an assessment of the gene expression profile further confirmed that the BM‑MSCs from patients with NMO were more vulnerable to senescence. Platelet‑derived growth factor (PDGF), as a major mitotic stimulatory factor for MSCs and a potent therapeutic cytokine in demyelinating disease, was able to overcome the decreased proliferation rate and increased senescence defects in BM‑MSCs from the patients with NMO. Taken together, the results from the present study have enabled the proposition of the possibility of combining the application of autologous BM‑MSCs and PDGF for refractory and severe patients with NMO in order to elicit improved therapeutic effects, or, at the least, to include PDGF as a necessary and standard growth factor in the current in vitro formula for the culture of NMO patient‑derived BM‑MSCs

Identification of a histone acetyltransferase as a novel regulator of Drosophila intestinal stem cells

AbstractOne of the major challenges in stem cell research is to decipher the controlling mechanisms/genes of stem cell homeostasis. Through an RNAi mediated genetic screen of living animals, we identified an evolutionarily conserved histone acetyltransferase Atac2 as a novel regulator of Drosophila intestinal stem cells (ISCs). Expression of Atac2-RNAi or a dominant negative allele of Atac2 generated more ISCs, while excessive Atac2 or a histone deacetylase inhibitor promoted ISC differentiation without affecting ISC survival or lineage specification. These findings extend our knowledge of epigenetic mechanisms in stem cell regulation

Explicit gain equations for hybrid graphene-quantum-dot photodetectors

Graphene is an attractive material for broadband photodetection but suffers from weak light absorption. Coating graphene with quantum dots can significantly enhance light absorption and create extraordinarily high photo gain. This high gain is often explained by the classical gain theory which is unfortunately an implicit function and may even be questionable. In this work, we managed to derive explicit gain equations for hybrid graphene-quantum-dot photodetectors. Due to the work function mismatch, lead sulfide (PbS) quantum dots coated on graphene will form a surface depletion region near the interface of quantum dots and graphene. Light illumination narrows down the surface depletion region, creating a photovoltage that gates the graphene. As a result, high photo gain in graphene is observed. The explicit gain equations are derived from the theoretical gate transfer characteristics of graphene and the correlation of the photovoltage with the light illumination intensity. The derived explicit gain equations fit well with the experimental data, from which physical parameters are extracted.Comment: 14 pages, 6 figure

Growth of Diamond Thin Film and Creation of NV Centers

Nitrogen-vacancy (NV) center is one type of special defects in diamonds. NV center not only can be used as sensors for temperature, stress detection, magnetic field, etc., but also has potential applications for quantum computing due to its unique physical properties. Therefore, the growth of diamond and creation of NV centers are significant for the future technologies. In this chapter, some methods for growing diamond thin film are introduced first, including traditional high-pressure-high-temperature (HPHT) and chemical vapor deposition (CVD) methods. The second part will focus on the current commonly used approaches to create NV centers. Inter-growth and post-growth processes are mainly utilized for the creation of NV centers during and after the growth of thin film, respectively

Improving End-to-End Text Image Translation From the Auxiliary Text Translation Task

End-to-end text image translation (TIT), which aims at translating the source language embedded in images to the target language, has attracted intensive attention in recent research. However, data sparsity limits the performance of end-to-end text image translation. Multi-task learning is a non-trivial way to alleviate this problem via exploring knowledge from complementary related tasks. In this paper, we propose a novel text translation enhanced text image translation, which trains the end-to-end model with text translation as an auxiliary task. By sharing model parameters and multi-task training, our model is able to take full advantage of easily-available large-scale text parallel corpus. Extensive experimental results show our proposed method outperforms existing end-to-end methods, and the joint multi-task learning with both text translation and recognition tasks achieves better results, proving translation and recognition auxiliary tasks are complementary.Comment: Accepted at the 26TH International Conference on Pattern Recognition (ICPR 2022

Transcriptome analysis reveals key differentially expressed genes involved in wheat grain development

AbstractWheat seed development is an important physiological process of seed maturation and directly affects wheat yield and quality. In this study, we performed dynamic transcriptome microarray analysis of an elite Chinese bread wheat cultivar (Jimai 20) during grain development using the GeneChip Wheat Genome Array. Grain morphology and scanning electron microscope observations showed that the period of 11–15days post-anthesis (DPA) was a key stage for the synthesis and accumulation of seed starch. Genome-wide transcriptional profiling and significance analysis of microarrays revealed that the period from 11 to 15 DPA was more important than the 15–20 DPA stage for the synthesis and accumulation of nutritive reserves. Series test of cluster analysis of differential genes revealed five statistically significant gene expression profiles. Gene ontology annotation and enrichment analysis gave further information about differentially expressed genes, and MapMan analysis revealed expression changes within functional groups during seed development. Metabolic pathway network analysis showed that major and minor metabolic pathways regulate one another to ensure regular seed development and nutritive reserve accumulation. We performed gene co-expression network analysis to identify genes that play vital roles in seed development and identified several key genes involved in important metabolic pathways. The transcriptional expression of eight key genes involved in starch and protein synthesis and stress defense was further validated by qRT-PCR. Our results provide new insight into the molecular mechanisms of wheat seed development and the determinants of yield and quality

miR-590-3p protects against ischaemia/reperfusion injury in an oxygen-glucose deprivation and reoxygenation cellular model by regulating HMGB1/TLR4/MyD88/NF-κB signalling

miR-590-3p has been reported to be reduced in myocardial ischaemia-reperfusion (I/R) injury, but its specific role in cerebral I/R injury is still uncertain. Thus, we explored the function and mechanism of miR590-3p in cerebral I/R injury using a cellular model. miR-590-3p, high mobility group Box 1 (HMGB1), and signalling-related factor levels were assessed using qPCR or a western blot analysis. Cell apoptosis was measured by flow cytometry. Inflammatory factors were detected by ELISA. The target of miR-590-3p was confirmed by dual-luciferase reporter assay and western blot analysis. We found that miR-590-3p was decreased and HMGB1 was increased in the OGD/R model. Upregulation of miR-590-3p reduced cell apoptosis and inflammation in the OGD/R model, and the TLR4/MyD88/NF-κB signalling pathway was suppressed. However, inhibition of miR-590-3p showed the opposite effects. Moreover, HMGB1 was verified as a target gene of miR-590-3p. HMGB1 reversed the decrease in apoptosis and inflammation caused by overexpression of miR590-3p, and the TLR4/MyD88/NF-κB signalling pathway was activated. Our results suggest that miR-590-3p regulates the TLR4/MyD88/NF-κB pathway by interacting with HMGB1 to protect against OGD/R-induced I/R injury. Thus, miR-590-3p may serve as a potential therapeutic target in cerebral I/R repair