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1.
Commun Biol ; 5(1): 297, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35393491

RESUMO

Native to the Americas, the invasive Spodoptera frugiperda (fall armyworm; FAW) was reported in West Africa in 2016, followed by its chronological detection across the Old World and the hypothesis of an eastward Asia expansion. We explored population genomic signatures of American and Old World FAW and identified 12 maternal mitochondrial DNA genome lineages across the invasive range. 870 high-quality nuclear single nucleotide polymorphic DNA markers identified five distinct New World population clusters, broadly reflecting FAW native geographical ranges and the absence of host-plant preferences. We identified unique admixed Old World populations, and admixed and non-admixed Asian FAW individuals, all of which suggested multiple introductions underpinning the pest's global spread. Directional gene flow from the East into eastern Africa was also detected, in contrast to the west-to-east spread hypothesis. Our study demonstrated the potential of population genomic approaches via international partnership to address global emerging pest threats and biosecurity challenges.


Assuntos
Fluxo Gênico , Metagenômica , Spodoptera , África Oriental , Animais , Ásia , Spodoptera/genética
2.
PeerJ ; 10: e12804, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35174014

RESUMO

Water yield is an ecosystem service that is vital to not only human life, but also sustainable development of the social economy and ecosystem. This study used annual average precipitation, potential evapotranspiration, plant available water content, soil depth, biophysical parameters, Zhang parameter, and land use/land cover (LULC) as input data for the Integrated Valuation of Ecosystem Service Tradeoffs (InVEST) model to estimate the water yield of Shangri-La City from 1974 to 2015. The spatiotemporal variations and associated factors (precipitation, evapotranspiration, LULC, and topographic factors) in water yield ecosystem services were then analyzed. The result showed that: (1) The water yield of Shangri-La City decreases from north and south to the center and showed a temporal trend from 1974 to 2015 of an initial decrease followed by an increase. Areas of higher average water yield were mainly in Hutiaoxia Town, Jinjiang Town, and Shangjiang Township. (2) Areas of importance for water yield in the study area which need to be assigned priority protection were mainly concentrated in the west of Jiantang Town, in central Xiaozhongdian Town, in central Gezan Township, in northwestern Dongwang Township, and in Hutiaoxia Town. (3) Water yield was affected by precipitation, evapotranspiration, vegetation type, and topographic factors. Water yield was positively and negatively correlated with precipitation and potential evapotranspiration, respectively. The average water yield of shrubs exceeded that of meadows and forests. Terrain factors indirectly affected the ecosystem service functions of water yield by affecting precipitation and vegetation types. The model used in this study can provide references for relevant research in similar climatic conditions.

3.
Mol Ecol Resour ; 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35007400

RESUMO

The cotton bollworm Helicoverpa armigera is a cosmopolitan pest and its diverse habitats plausibly contribute to the formation of diverse lineages. Despite the significant threat it poses to economic crops worldwide, its evolutionary history and genetic basis of local adaptation are poorly understood. In this study, we de novo assembled a high-quality chromosome-level reference genome of H. a. armigera (contig N50 = 7.34 Mb), with 99.13% of the HaSCD2 assembly assigned to 31 chromosomes (Z-chromosome + 30 autosomes). We constructed an ultradense variation map across 14 cotton bollworm populations and identified a novel lineage in northwestern China. Historical inference showed that effective population size changes coincided with global temperature fluctuation. We identified nine differentiated genes in the three H. armigera lineages (H. a. armigera, H. a. conferta and the new northwestern Chinese lineage), of which per and clk genes are involved in circadian rhythm. Selective sweep analyses identified a series of Gene Ontology categories related to climate adaptation, feeding behaviour and insecticide tolerance. Our findings reveal fundamental knowledge of the local adaptation of different cotton bollworm lineages and will guide the formulation of cotton bollworm management measures at different scales.

4.
IEEE Trans Image Process ; 31: 894-905, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34951847

RESUMO

Accurate gland segmentation in histology tissue images is a critical but challenging task. Although deep models have demonstrated superior performance in medical image segmentation, they commonly require a large amount of annotated data, which are hard to obtain due to the extensive labor costs and expertise required. In this paper, we propose an intra- and inter-pair consistency-based semi-supervised (I2CS) model that can be trained on both labeled and unlabeled histology images for gland segmentation. Considering that each image contains glands and hence different images could potentially share consistent semantics in the feature space, we introduce a novel intra- and inter-pair consistency module to explore such consistency for learning with unlabeled data. It first characterizes the pixel-level relation between a pair of images in the feature space to create an attention map that highlights the regions with the same semantics but on different images. Then, it imposes a consistency constraint on the attention maps obtained from multiple image pairs, and thus filters low-confidence attention regions to generate refined attention maps that are then merged with original features to improve their representation ability. In addition, we also design an object-level loss to address the issues caused by touching glands. We evaluated our model against several recent gland segmentation methods and three typical semi-supervised methods on the GlaS and CRAG datasets. Our results not only demonstrate the effectiveness of the proposed due consistency module and Obj-Dice loss, but also indicate that the proposed I2CS model achieves state-of-the-art gland segmentation performance on both benchmarks.


Assuntos
Técnicas Histológicas , Semântica , Benchmarking , Processamento de Imagem Assistida por Computador
5.
Sci Total Environ ; 806(Pt 2): 150597, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34592298

RESUMO

Despite the awareness that green water is the main source of water to produce food, studies on green water use in cropland ecosystems are still rather limited, and almost no research has so far explored the relationship between green water utilization and socioeconomic development. In this study, with the help of CropWat 8.0, the green water footprint (GWF) of main crops in China was estimated from 1979 to 2016. On this basis, a novel concept, i.e., green water appropriation rate (GWar), was introduced to reveal the relationship between GWF and precipitation. Then, for the first time, the center of gravity trajectory of the GWar and the correlation between GWar and socioeconomic factors were further investigated. The results show that the provinces with the largest increases of GWF were Inner Mongolia (223%), Xinjiang (127%), and Ningxia (123%), while the GWF of 11 provinces has decreased, and 9 of them were municipalities or coastal areas. Generally, the GWar in the eastern and central provinces was higher than that in the western provinces. The center of gravity of the GWar has always been in Henan Province, but it has moved westward from Kaifeng City in 1979 to Sanmenxia City in 2016 and may further move to Shanxi Province soon. The total power of agricultural machinery and the effective irrigation rate had a positive correlation with the GWar, while the agricultural GDP was negatively correlated with the GWar. It is expected that the results will explicitly provide a scientific basis for the development of water-appropriate agriculture and the full utilization of rainwater.


Assuntos
Ecossistema , Água , Agricultura , China , Produtos Agrícolas , Água/análise
6.
Polymers (Basel) ; 13(16)2021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34451292

RESUMO

The cavity pressure in the injection molding process is closely related to the quality of the molded products, and is used for process monitoring and control, to upgrade the quality of the molded products. The experimental platform was built to carry out the cavity pressure experiment with a micro spline injection mold in the paper. The process parameters were changed, such as V/P switchover, mold temperature, melt temperature, packing pressure, and injection rate, in order to analyze the influence of the process parameters on the product weight. The peak cavity pressure and area under the pressure curve were the two attributes utilized in investigating the correlation between cavity pressure and part weight. The experimental results show that the later switchover allowed the injection to proceed longer and produce a heavier tensile specimen. By comparing different cavity pressure curves, the general shapes of the curves were able to indicate different types of shortage produced. When the V/P switchover position is 10 mm, the coefficient of determination (R2 value) of part weight, for the peak cavity pressure and area under the curve, were 0.7706 and 0.8565, respectively. This showed that the area under the curve appeared to be a better process and quality indicator than the peak cavity pressure.

7.
PLoS Genet ; 17(7): e1009680, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34252082

RESUMO

The evolution of insecticide resistance represents a global constraint to agricultural production. Because of the extreme genetic diversity found in insects and the large numbers of genes involved in insecticide detoxification, better tools are needed to quickly identify and validate the involvement of putative resistance genes for improved monitoring, management, and countering of field-evolved insecticide resistance. The avermectins, emamectin benzoate (EB) and abamectin are relatively new pesticides with reduced environmental risk that target a wide number of insect pests, including the beet armyworm, Spodoptera exigua, an important global pest of many crops. Unfortunately, field resistance to avermectins recently evolved in the beet armyworm, threatening the sustainable use of this class of insecticides. Here, we report a high-quality chromosome-level assembly of the beet armyworm genome and use bulked segregant analysis (BSA) to identify the locus of avermectin resistance, which mapped on 15-16 Mbp of chromosome 17. Knockout of the CYP9A186 gene that maps within this region by CRISPR/Cas9 gene editing fully restored EB susceptibility, implicating this gene in avermectin resistance. Heterologous expression and in vitro functional assays further confirm that a natural substitution (F116V) found in the substrate recognition site 1 (SRS1) of the CYP9A186 protein results in enhanced metabolism of EB and abamectin. Hence, the combined approach of coupling gene editing with BSA allows for the rapid identification of metabolic resistance genes responsible for insecticide resistance, which is critical for effective monitoring and adaptive management of insecticide resistance.


Assuntos
Sistema Enzimático do Citocromo P-450/genética , Resistência a Inseticidas/genética , Spodoptera/genética , Animais , Mapeamento Cromossômico/métodos , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Edição de Genes/métodos , Genoma/genética , Inseticidas/farmacologia , Ivermectina/análogos & derivados , Ivermectina/farmacologia , Larva/genética , Spodoptera/metabolismo
8.
Psychiatr Danub ; 33(2): 209-216, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34185752

RESUMO

BACKGROUND: This study aims to explore the intervention effect of research-based psychological counseling on adolescents' mental health during the COVID-19 epidemic. SUBJECTS AND METHODS: From May to July 2020, 160 young students were selected from 5 middle schools in Shandong Province of China as the participants of this study and were randomly divided into the experiment and control groups with 80 members in each group. The routine in-campus education of health knowledge related to the epidemic was conducted in the control group, while the experiment group received both the routine education and the intervention of psychological counseling in combination with outdoor exercise. RESULTS: No significant difference exists between the experiment and control groups (P>0.05) before the intervention, but the scores of the experiment group in anxiety and depression are lower than those of the control group (P<0.05) after the intervention; the PSQI score of the experiment group is significantly lower after the intervention, suggesting that the effect on the experiment group is better than the control group (P<0.05); the scores of the experiment group in psychological resilience and its 5 dimensions are higher than those of the control group (P<0.05). CONCLUSIONS: This intervention model has a good intervention effect on adolescents' mental health and psychological resilience. At the same time, this study enlightens the introduction of the research-based psychological counseling model when helping adolescents solve mental health problems and highlights the important role of exercise in improving adolescents' mental health and psychological resilience.


Assuntos
COVID-19 , Epidemias , Adolescente , China , Aconselhamento , Humanos , Saúde Mental , SARS-CoV-2
9.
Chem Biodivers ; 18(7): e2001047, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34000082

RESUMO

Triple-negative breast cancer (TNBC) makes up 15 % to 20 % of all breast cancer (BC) cases, and represents one of the most challenging malignancies to treat. For many years, chemotherapy has been the main treatment option for TNBC. Natural products isolated from marine organisms and terrestrial organisms with great structural diversity and high biochemical specificity form a compound library for the assessment and discovery of new drugs. In this review, we mainly focused on natural compounds and extracts (from marine and terrestrial environments) with strong anti-TNBC activities (IC50 <100 µM) and their possible mechanisms reported in the past six years (2015-2021).


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Produtos Biológicos/farmacologia , Extratos Vegetais/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Conformação Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Neoplasias de Mama Triplo Negativas/patologia
10.
Nat Prod Res ; 35(10): 1620-1626, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-31232106

RESUMO

Three new sesquiterpene quinones/hydroquinones, 20-demethoxy-20-isopentylaminodactyloquinone D (1), 20-demethoxy-20-isobutylaminodactyloquinone D (2), and 19-methoxy-dictyoceratin-A (3), and five known related compounds (4-8) were isolated from the marine sponge Dactylospongia elegans. Their structures were elucidated by spectroscopic analysis, ECD calculation, single-crystal X-ray diffraction, and comparison with the literature. Compounds 3 and 5-8 exhibited activities against the human cancer cell lines DU145, SW1990, Huh7, and PANC-1 with IC50 values ranging from 2.33 to 37.85 µM.


Assuntos
Organismos Aquáticos/química , Poríferos/química , Terpenos/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Terpenos/química
11.
IEEE Trans Med Imaging ; 40(1): 286-296, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32956049

RESUMO

Medical image segmentation is an essential task in computer-aided diagnosis. Despite their prevalence and success, deep convolutional neural networks (DCNNs) still need to be improved to produce accurate and robust enough segmentation results for clinical use. In this paper, we propose a novel and generic framework called Segmentation-Emendation-reSegmentation-Verification (SESV) to improve the accuracy of existing DCNNs in medical image segmentation, instead of designing a more accurate segmentation model. Our idea is to predict the segmentation errors produced by an existing model and then correct them. Since predicting segmentation errors is challenging, we design two ways to tolerate the mistakes in the error prediction. First, rather than using a predicted segmentation error map to correct the segmentation mask directly, we only treat the error map as the prior that indicates the locations where segmentation errors are prone to occur, and then concatenate the error map with the image and segmentation mask as the input of a re-segmentation network. Second, we introduce a verification network to determine whether to accept or reject the refined mask produced by the re-segmentation network on a region-by-region basis. The experimental results on the CRAG, ISIC, and IDRiD datasets suggest that using our SESV framework can improve the accuracy of DeepLabv3+ substantially and achieve advanced performance in the segmentation of gland cells, skin lesions, and retinal microaneurysms. Consistent conclusions can also be drawn when using PSPNet, U-Net, and FPN as the segmentation network, respectively. Therefore, our SESV framework is capable of improving the accuracy of different DCNNs on different medical image segmentation tasks.


Assuntos
Processamento de Imagem Assistida por Computador , Dermatopatias , Diagnóstico por Computador , Humanos , Redes Neurais de Computação
12.
Insect Sci ; 28(3): 627-638, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32558234

RESUMO

The fall armyworm (FAW), Spodoptera frugiperda, is a major pest native to the Americas that has recently invaded the Old World. Point mutations in the target-site proteins acetylcholinesterase-1 (ace-1), voltage-gated sodium channel (VGSC) and ryanodine receptor (RyR) have been identified in S. frugiperda as major resistance mechanisms to organophosphate, pyrethroid and diamide insecticides respectively. Mutations in the adenosine triphosphate-binding cassette transporter C2 gene (ABCC2) have also been identified to confer resistance to Cry1F protein. In this study, we applied a whole-genome sequencing (WGS) approach to identify point mutations in the target-site genes in 150 FAW individuals collected from China, Malawi, Uganda and Brazil. This approach revealed three amino acid substitutions (A201S, G227A and F290V) of S. frugiperda ace-1, which are known to be associated with organophosphate resistance. The Brazilian population had all three ace-1 point mutations and the 227A allele (mean frequency = 0.54) was the most common. Populations from China, Malawi and Uganda harbored two of the three ace-1 point mutations (A201S and F290V) with the 290V allele (0.47-0.58) as the dominant allele. Point mutations in VGSC (T929I, L932F and L1014F) and RyR (I4790M and G4946E) were not detected in any of the 150 individuals. A novel 12-bp insertion mutation in exon 15 of the ABCC2 gene was identified in some of the Brazilian individuals but absent in the invasive populations. Our results not only demonstrate robustness of the WGS-based genomic approach for detection of resistance mutations, but also provide insights for improvement of resistance management tactics in S. frugiperda.


Assuntos
Toxinas de Bacillus thuringiensis/farmacologia , Endotoxinas/farmacologia , Proteínas Hemolisinas/farmacologia , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Spodoptera , Acetilcolinesterase/genética , Animais , Diamida/farmacologia , Genes de Insetos , Genoma de Inseto , Organofosfatos/farmacologia , Mutação Puntual/genética , Mutação Puntual/fisiologia , Piretrinas/farmacologia , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Spodoptera/efeitos dos fármacos , Spodoptera/genética , Canais de Sódio Disparados por Voltagem/genética , Sequenciamento Completo do Genoma
13.
IEEE Trans Med Imaging ; 40(2): 661-672, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33125324

RESUMO

Automated and accurate 3D medical image segmentation plays an essential role in assisting medical professionals to evaluate disease progresses and make fast therapeutic schedules. Although deep convolutional neural networks (DCNNs) have widely applied to this task, the accuracy of these models still need to be further improved mainly due to their limited ability to 3D context perception. In this paper, we propose the 3D context residual network (ConResNet) for the accurate segmentation of 3D medical images. This model consists of an encoder, a segmentation decoder, and a context residual decoder. We design the context residual module and use it to bridge both decoders at each scale. Each context residual module contains both context residual mapping and context attention mapping, the formal aims to explicitly learn the inter-slice context information and the latter uses such context as a kind of attention to boost the segmentation accuracy. We evaluated this model on the MICCAI 2018 Brain Tumor Segmentation (BraTS) dataset and NIH Pancreas Segmentation (Pancreas-CT) dataset. Our results not only demonstrate the effectiveness of the proposed 3D context residual learning scheme but also indicate that the proposed ConResNet is more accurate than six top-ranking methods in brain tumor segmentation and seven top-ranking methods in pancreas segmentation.


Assuntos
Neoplasias Encefálicas , Processamento de Imagem Assistida por Computador , Humanos , Imageamento Tridimensional , Redes Neurais de Computação , Tomografia Computadorizada por Raios X
14.
IEEE Trans Med Imaging ; 40(3): 879-890, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33245693

RESUMO

Clusters of viral pneumonia occurrences over a short period may be a harbinger of an outbreak or pandemic. Rapid and accurate detection of viral pneumonia using chest X-rays can be of significant value for large-scale screening and epidemic prevention, particularly when other more sophisticated imaging modalities are not readily accessible. However, the emergence of novel mutated viruses causes a substantial dataset shift, which can greatly limit the performance of classification-based approaches. In this paper, we formulate the task of differentiating viral pneumonia from non-viral pneumonia and healthy controls into a one-class classification-based anomaly detection problem. We therefore propose the confidence-aware anomaly detection (CAAD) model, which consists of a shared feature extractor, an anomaly detection module, and a confidence prediction module. If the anomaly score produced by the anomaly detection module is large enough, or the confidence score estimated by the confidence prediction module is small enough, the input will be accepted as an anomaly case (i.e., viral pneumonia). The major advantage of our approach over binary classification is that we avoid modeling individual viral pneumonia classes explicitly and treat all known viral pneumonia cases as anomalies to improve the one-class model. The proposed model outperforms binary classification models on the clinical X-VIRAL dataset that contains 5,977 viral pneumonia (no COVID-19) cases, 37,393 non-viral pneumonia or healthy cases. Moreover, when directly testing on the X-COVID dataset that contains 106 COVID-19 cases and 107 normal controls without any fine-tuning, our model achieves an AUC of 83.61% and sensitivity of 71.70%, which is comparable to the performance of radiologists reported in the literature.


Assuntos
Aprendizado Profundo , Pneumonia Viral/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , COVID-19/diagnóstico por imagem , Humanos , SARS-CoV-2
15.
BMC Dev Biol ; 20(1): 22, 2020 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-33203369

RESUMO

BACKGROUND: Tissue regeneration mediated by mesenchymal stem cells (MSCs) is deemed a desirable way to repair teeth and craniomaxillofacial tissue defects. Nevertheless, the molecular mechanisms about cell proliferation and committed differentiation of MSCs remain obscure. Previous researches have proved that lysine demethylase 2A (KDM2A) performed significant function in the regulation of MSC proliferation and differentiation. SNRNP200, as a co-binding factor of KDM2A, its potential effect in regulating MSCs' function is still unclear. Therefore, stem cells from the apical papilla (SCAPs) were used to investigate the function of SNRNP200 in this research. METHODS: The alkaline phosphatase (ALP) activity assay, Alizarin Red staining, and osteogenesis-related gene expressions were used to examine osteo-/dentinogenic differentiation potential. Carboxyfluorescein diacetate, succinimidyl ester (CFSE) and cell cycle analysis were applied to detect the cell proliferation. Western blot analysis was used to evaluate the expressions of cell cycle-related proteins. RESULTS: Depletion of SNRNP200 caused an obvious decrease of ALP activity, mineralization formation and the expressions of osteo-/dentinogenic genes including RUNX2, DSPP, DMP1 and BSP. Meanwhile, CFSE and cell cycle assays revealed that knock-down of SNRNP200 inhibited the cell proliferation and blocked cell cycle at the G2/M and S phase in SCAPs. In addition, it was found that depletion of SNRNP200 up-regulated p21 and p53, and down-regulated the CDK1, CyclinB, CyclinE and CDK2. CONCLUSIONS: Depletion of SNRNP200 repressed osteo-/dentinogenic differentiation potentials and restrained cell proliferation through blocking cell cycle progression at the G2/M and S phase, further revealing that SNRNP200 has crucial effects on preserving the proliferation and differentiation potentials of dental tissue-derived MSCs.


Assuntos
Diferenciação Celular , Proliferação de Células , Papila Dentária/citologia , Células-Tronco Mesenquimais/citologia , Ribonucleoproteínas Nucleares Pequenas/metabolismo , Pontos de Checagem do Ciclo Celular/genética , Células Cultivadas , Senescência Celular/genética , Papila Dentária/crescimento & desenvolvimento , Dentinogênese , Proteínas F-Box/metabolismo , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Histona Desmetilases com o Domínio Jumonji/metabolismo , Osteogênese , Ligação Proteica , Ribonucleoproteínas Nucleares Pequenas/genética
16.
Stem Cells Int ; 2020: 8881021, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33082788

RESUMO

Understanding the regulation mechanisms of mesenchymal stem cells (MSCs) can assist in tissue regeneration. The histone demethylase (KDM) family has a crucial role in differentiation and cell proliferation of MSCs, while the function of KDM3B in MSCs is not well understood. In this study, we used the stem cells from the apical papilla (SCAPs) to test whether KDM3B could regulate the function of MSCs. By an alkaline phosphatase (ALP) activity assay, Alizarin red staining, real-time RT-PCR, and western blot analysis, we found that KDM3B enhanced the ALP activity and mineralization of SCAPs and promoted the expression of runt-related transcription factor 2 (RUNX2), osterix (OSX), dentin sialophosphoprotein (DSPP), and osteocalcin (OCN). Additionally, the CFSE, CCK-8, and flow cytometry assays revealed that KDM3B improved cell proliferation by accelerating cell cycle transition from the G1 to S phase. Scratch and transwell migration assays displayed that KDM3B promoted the migration potential of SCAPs. Mechanically, microarray results displayed that 98 genes were upregulated, including STAT1, CCND1, and FGF5, and 48 genes were downregulated after KDM3B overexpression. Besides, we found that the Toll-like receptor and JAK-STAT signaling pathway may be involved in the regulating function of KDM3B in SCAPs. In brief, we discovered that KDM3B promoted the osteo-/odontogenic differentiation, cell proliferation, and migration potential of SCAPs and provided a novel target and theoretical basis for regenerative medicine.

17.
Dose Response ; 18(3): 1559325820950061, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32973416

RESUMO

Increasing evidence shows that eukaryotic initiation factor subunit (EIF3C) plays a crucial role in development of tumors. However, the underlying roles of EIF3Cin the development of pancreatic cancer (PC) remain unknown. In this study, we examined the expression of EIF3C in PC tissues, their adjacent normal tissues and 3 cell lines (SW1990, PANC-1 and AsPC-1). Moreover, the EIF3C-shRNA lentivirus was constructed to suppress EIF3C expression. Following this, the cell colony formation assay was employed to evaluate proliferation ability of PC cells. Meanwhile, the cell cycle and apoptotic assays were also performed by flow cytometry. We found that level of EIF3C in PC tissues was significantly increased compared with that in adjacent normal tissues. Furthermore, the knockdown of EIF3C can significantly reduce cell proliferation, block cell cycle in G2/M and induce apoptosis in both SW1990 and PANC-1 cells. Our findings suggest that EIF3C plays a crucial role in the progression of PC and may be a potential target in the treatment of PC.

18.
Stem Cell Res Ther ; 11(1): 271, 2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32631410

RESUMO

BACKGROUND: Mesenchymal stem cell (MSC)-based cartilage tissue regeneration is a treatment with great potential. How to enhance the MSC chondrogenic differentiation is a key issue involved in cartilage formation. In the present study, we seek to expound the phenotypes and mechanisms of DLX5 in chondrogenic differentiation function in MSCs. METHODS: Stem cells from apical papilla (SCAPs) were used. The Alcian Blue staining, pellet culture system, and cell transplantation in rabbit knee cartilage defect were used to evaluate the chondrogenic differentiation function of MSCs. Western blot, real-time RT-PCR, and ChIP assays were used to evaluate the molecular mechanisms. RESULTS: DLX5 and HOXC8 expressions were upregulated during chondrogenic differentiation. In vitro results showed that DLX5 and HOXC8 enhanced the expression of chondrogenic markers including collagen II (COL2), collagen V (COL5), and sex-determining region Y box protein 9 (SOX9) and promoted the chondrogenic differentiation and the formation of cartilage clumps in the pellet culture system. Mechanically, DLX5 and HOXC8 formed protein complexes and negatively regulated the LncRNA, LINC01013, via directly binding its promoter. In vivo transplantation experiment showed that DLX5 and HOXC8 could restore the cartilage defect in the rabbit knee model. In addition, knock-down of LINC01013 enhanced the chondrogenic differentiation of SCAPs. CONCLUSIONS: In conclusion, DLX5 and HOXC8 enhance the chondrogenic differentiation abilities of SCAPs by negatively regulating LINC01013 in SCAPs, and provided the potential target for promoting cartilage tissue regeneration.


Assuntos
Condrogênese , Células-Tronco Mesenquimais , Animais , Cartilagem , Diferenciação Celular , Células Cultivadas , Condrogênese/genética , Coelhos , Células-Tronco
19.
Oncol Lett ; 19(3): 1683-1692, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32194660

RESUMO

The underlying molecular mechanisms of pancreatic neuroendocrine tumor (pNET) development have not yet been clearly identified. The present study revealed that thrombospondin 2 (THBS2) was downregulated in pNET tissues and cells. Forced expression of THBS2 inhibited the proliferation and migration of pNET cells in vitro. MicroRNA(miR)-744-5p was indicated to be a direct regulator of THBS2. Upregulation of miR-744-5p potentially caused THBS2 repression. Furthermore, THBS2 inhibited the production of matrix metalloproteinase (MMP) MMP9 through suppressing the transcriptional activity of CUT-like homeobox 1 (CUX1). CUX1 and MMP9 mediated the effect of THBS2 on pNET proliferation and migration, respectively. The results of the present study revealed a mechanistic role for THBS2 in pNET proliferation and migration, indicating that THBS2 was downregulated by miR-744-5p and further affected the CUX1/MMP9 cascade, which promoted the development of pNET.

20.
IEEE Trans Med Imaging ; 39(7): 2482-2493, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32070946

RESUMO

Automated skin lesion segmentation and classification are two most essential and related tasks in the computer-aided diagnosis of skin cancer. Despite their prevalence, deep learning models are usually designed for only one task, ignoring the potential benefits in jointly performing both tasks. In this paper, we propose the mutual bootstrapping deep convolutional neural networks (MB-DCNN) model for simultaneous skin lesion segmentation and classification. This model consists of a coarse segmentation network (coarse-SN), a mask-guided classification network (mask-CN), and an enhanced segmentation network (enhanced-SN). On one hand, the coarse-SN generates coarse lesion masks that provide a prior bootstrapping for mask-CN to help it locate and classify skin lesions accurately. On the other hand, the lesion localization maps produced by mask-CN are then fed into enhanced-SN, aiming to transfer the localization information learned by mask-CN to enhanced-SN for accurate lesion segmentation. In this way, both segmentation and classification networks mutually transfer knowledge between each other and facilitate each other in a bootstrapping way. Meanwhile, we also design a novel rank loss and jointly use it with the Dice loss in segmentation networks to address the issues caused by class imbalance and hard-easy pixel imbalance. We evaluate the proposed MB-DCNN model on the ISIC-2017 and PH2 datasets, and achieve a Jaccard index of 80.4% and 89.4% in skin lesion segmentation and an average AUC of 93.8% and 97.7% in skin lesion classification, which are superior to the performance of representative state-of-the-art skin lesion segmentation and classification methods. Our results suggest that it is possible to boost the performance of skin lesion segmentation and classification simultaneously via training a unified model to perform both tasks in a mutual bootstrapping way.


Assuntos
Melanoma , Dermatopatias , Neoplasias Cutâneas , Dermoscopia , Humanos , Redes Neurais de Computação , Neoplasias Cutâneas/diagnóstico por imagem
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