Limited attention has been given to the persistent impacts of diverse herbicides present in soil on the growth of successive crops in agricultural production. Therefore, the objective of this ...experiment is to thoroughly examine atrazine residues toxic reactions in lucern (Medicago sativa L.). This experiment aims to thoroughly investigate the toxic response of atrazine in lucern. Lucern sourced from Henan Seed Company in China. The study employed the soil addition method to investigate the impacts and correlations of diverse concentrations of atrazine herbicide residues with growth indicators, photosynthetic features, chlorophyll fluorescence parameters of lucern. The results showed that with the increase of atrazine residue (0.0-2.0 mg·kg-1), the plant height (PH), root length (RL), stem dry weight (SDW) and root dry weight (RDW) decreased to 81.8%, 81.7%, 92.3% and 85.2%, respectively. SPAD value, net photosynthetic rate (Pn), stomatal conductance (GS), transpiration rate (Tr), the PSII maximum quantum yield (Fv/Fo), maximum photochemical efficiency (Fv/Fm), actual photosynthetic efficiency (Y(Ⅱ)), PSII coefficient of photochemical fluorescence quenching (qP) and photosynthetic electron transport rate (ETR) decrease by 62.1%, 83.4%, 84.1%, 95.7%, 76.8%, 11.8%, 84.5%, 46.1% and 63.1%, respectively. However, the intercellular carbon dioxide concentration (Ci) and non-photochemical quenching coefficient (NPQ) increased by 46.2% and 37.5%, respectively. Ci was positively correlated with Fv/Fo, Fv/Fm, qP, Y(II) and ETR (P<0.01), SPAD, Pn and Gs were significantly negatively correlated with Tr (P<0.01), were significantly positively correlated with Tr, Fv/Fo, Fv/Fm, qP, Y(II) and ETR (P<0.01). The potential toxicity risk of atrazine residues to plants was assessed by photosynthetic characteristics and chlorophyll fluorescence parameters. Although herbicide application is essential for food production, appropriate concentration management methods must be adopted to ensure the sustainable development of agricultural ecology.
Myelodysplastic syndrome (MDS), a largely incurable hematological malignancy, is derived from aberrant clonal hematopoietic stem/progenitor cells (HSPCs) that persist after conventional therapies. ...Defining the mechanisms underlying MDS HSPC maintenance is critical for developing MDS therapy. The deacetylase SIRT1 regulates stem cell proliferation, survival, and self-renewal by deacetylating downstream proteins. Here we show that SIRT1 protein levels were downregulated in MDS HSPCs. Genetic or pharmacological activation of SIRT1 inhibited MDS HSPC functions, whereas SIRT1 deficiency enhanced MDS HSPC self-renewal. Mechanistically, the inhibitory effects of SIRT1 were dependent on TET2, a safeguard against HSPC transformation. SIRT1 deacetylated TET2 at conserved lysine residues in its catalytic domain, enhancing TET2 activity. Our genome-wide analysis identified cancer-related genes regulated by the SIRT1/TET2 axis. SIRT1 activation also inhibited functions of MDS HSPCs from patients with TET2 heterozygous mutations. Altogether, our results indicate that restoring TET2 function through SIRT1 activation represents a promising means to target MDS HSPCs.
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•SIRT1 depletion enhances MDS HSPC self-renewal and growth•SIRT1 insufficiency in MDS promotes TET2 hyperacetylation•SIRT1 agonist treatment blocks MDS HSPC maintenance•SIRT1 activation deacetylates TET2 and enhances its catalytic activity
An improved understanding of the mechanisms regulating myelodysplastic syndrome (MDS) hematopoietic stem/progenitor cell (HSPC) growth and self-renewal is critical for developing MDS therapy. Sun et al. report that SIRT1 deficiency-induced TET2 hyperacetylation promotes MDS HSPC function and provides an approach to target MDS HSPCs by activating SIRT1 deacetylase.
Exosomes are 30–120 nm-sized membrane vesicles of endocytic origin that are released into the extracellular environment and play roles in cell–cell communication. Tumor-associated macrophages (TAMs) ...are important constituents of the tumor microenvironment; thus, it is critical to study the features and complex biological functions of TAM-derived exosomes. Here, we constructed a TAM cell model from a mouse macrophage cell line, Ana-1, and performed comparative proteomics on exosomes, exosome-free media, and cells between TAMs and Ana-1. Proteomic analysis between exosome and exosome-free fractions indicated that the functions of exosome dominant proteins were mainly enriched in RNA processing and proteolysis. TAM status dramatically affected the abundances of 20S proteasome subunits and ribosomal proteins in their exosomes. The 20S proteasome activity assay strongly indicated that TAM exosomes possessed higher proteolytic activity. In addition, Ana-1- and TAM-derived exosomes have different RNA profiles, which may result from differential RNA processing proteins. Taken together, our comprehensive proteomics study provides novel views for understanding the complicated roles of macrophage-derived exosomes in the tumor microenvironment.
In semantic segmentation, category-hidden attack is a malicious adversarial attack which manipulates a specific category without affecting the recognition of other objects. A popular method is the ...nearest-neighbor algorithm, which modifies the segmentation map by replacing a target category with other categories close to it. Nearest-neighbor method aims to restrict the strength of perturbation noise that is imperceptive to both human eyes and segmentation algorithms. However, its spatial search adds lots of computational burden. In this paper, we propose two fast methods, dot-based method and line-based method, which are able to quickly complete the category transfers in logits maps without spatial search. The advantages of our two methods result from generating the logits maps by modifying the probability distribution of the category channels. Both of our methods are global, and the location and size of objects to hide are not cared, so their processing speed is very fast. The dot-based algorithm takes the pixel as the unit of calculation, and the line-based algorithm combines the category distribution characteristics of the horizontal direction to calculate. Experiments verify the effectiveness and efficiency compared with nearest-neighbor method. Specifically, in the segmentation map modification step, our methods are 5 times and 65 times faster than nearest-neighbor, respectively. In the small perturbation attack experiment, dot-based method gets the fastest speed, while different datasets and different setting experiments indicate that the line-based method is able to achieve faster and better adversarial segmentation results in most cases.
Oxidative stress is thought to contribute to cancer development. Epstein-Barr virus (EBV) and its encoded oncoprotein, latent membrane protein 1 (LMP1), are closely associated with the transformation ...of nasopharyngeal carcinoma (NPC) and Burkitt's lymphoma (BL). In this study, we used LMP1-transformed NP cells and EBV-related malignant cell lines to assess the effects of LMP1 on reactive oxygen species (ROS) accumulation and glycolytic activity. Using NPC tissue samples and a tissue array to address clinical implications, we report that LMP1 activates NAD(P)H oxidases to generate excessive amount of ROS in EBV-related malignant diseases. By evaluating NAD(P)H oxidase (NOX) subunit expression, we found that the expression of the NAD(P)H oxidase regulatory subunit p22phox was significantly upregulated upon LMP1-induced transformation. Furthermore, this upregulation was mediated by the c-Jun N-terminal kinase (JNK) pathway. In addition, LMP1 markedly stimulated anaerobic glycolytic activity through the PI3K/Akt pathway. Additionally, in both NPC cells and tissue samples, p22phox expression correlated with LMP1 expression. The NAD(P)H oxidase inhibitor diphenyleneiodonium (DPI) also exerted a marked cytotoxic effect in LMP1-transformed and malignant cells, providing a novel strategy for anticancer therapy.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Nucleophosmin (NPM1) is a widely expressed nucleocytoplasmic shuttling protein with prominent nucleolar localization. It is estimated that 25-35% of adult patients with acute myeloid leukemia (AML) ...carry NPM1 mutations. The classic NPM1 type A mutation occurs in exon 12, which accounts for 75-80% of adult patients with NPM1-mutated AML. It produces an additional leucine and valine-rich nuclear export signal (NES) at the C-terminus, and causes aberrant cytoplasmic dislocation of NPM1 protein. Notably, emerging evidence indicates that besides the classic type A mutation, rare mutants occurring in other exons may also lead to the imbalance of the nucleocytoplasmic shuttle of NPM1. Identification of novel non-type A mutants is crucial for the diagnosis, prognosis, risk stratification and disease monitoring of potential target populations. Here we reported a novel NPM1 mutation in exon 5 identified from a de novo AML patient. Similar to the classic type A mutation, the exon 5 mutation had the NPM1 mutant bound to exportin-1 and directed the mutant into the cytoplasm by generating an additional NES sequence, resulting in aberrant cytoplasmic dislocation of NPM1 protein, which could be reversed by exportin-1 inhibitor leptomycin B. Our findings strongly support that besides the exon 12 mutation, the exon 5 mutant is another NPM1 "born to be exported" mutant critical for leukemogenesis. Therefore, similar to the classic type A mutation, the identification of our novel NPM1 mutation is beneficial for clinical laboratory diagnosis, genetic risk assessment and MRD monitoring. Keywords: NPM1 mutation, Acute myeloid leukemia, Aberrant cytoplasmic dislocation, Nuclear export signal, Prognosis
Today, with the rapid development of science and technology, the era of big data has been proposed and triggered reforms in all walks of life. Face recognition is a biometric recognition method with ...the characteristics of non-contact, non mandatory, friendly and harmonious, which has a good application prospect in the fields of national security and social security. With the deepening of the research on face recognition, small-scale face recognition has achieved good recognition results, but in the era of big data, the existing small-scale face recognition methods have gradually failed to meet the social needs, and how to get a good face recognition effect in the era of big data has become a new research hotspot. Based on this, this paper aims to optimize the existing face recognition algorithm, study the face recognition method driven by big data, and propose a deep learning multi feature fusion face recognition algorithm driven by big data. First, for the problem that 2DPCA (Two-dimensional Principle Component Analysis) can well extract the global features of the face under large samples, but the local features of the face are difficult to process, this paper uses the LBP (Local Binary Pattern, LBP) algorithm to extract the texture features of the face, and the extracted texture features are integrated with the global features extracted by 2DPCA to multi-feature fusion, so that the fused features can take into account both global and local features, and have better recognition results. Then using the obtained fusion features as input, training in a convolutional neural network, and measuring the similarity based on the feature vectors of the sample set and the training set after the training, can realize multi-feature fusion face recognition. Through the analysis of simulation experiments, it is found that, compared with the use of global features or local features alone, the fusion features obtained by multi-feature fusion of global features extracted by 2DPCA and local features extracted by LBP algorithm have better recognition effect in the big data environment. After convolutional neural network trains and recognizes this feature, a high recognition accuracy rate is obtained, which can show that the face recognition method designed in this paper has good application potential in the era of big data. In the background of big data, the accuracy of face recognition can reach more than 90%, which can meet the needs of society well.
•This paper aims to optimize the existing face recognition algorithm.•This paper uses the LBP algorithm to extract the texture features of the face.•This method fuse local & global features of human face in big data background.•The accuracy of face recognition reaches more than 90%.
Caudal paramedian midbrain infarction (CPMI) is an extremely rare form of ischemic stroke and related clinical studies are scarce. Our aim is to investigate the clinical features, neuroradiological ...findings and stroke etiology of CPMI. We conducted a retrospective study of 12 patients with CPMI, confirmed by diffusion-weighted MRI from 6820 cerebral infarction patients at our stroke center from January 2012 to August 2018. Experienced neurologists evaluated the clinical manifestations, neuroimaging findings and stroke mechanisms. Twelve patients (11 men, 1 woman) aged 42–81 years old met the study inclusion criteria. Seven patients had a unilateral infarction (two right-sided, five left-sided) and five had bilateral infarctions. Sagittal image showed a backward oblique sign in the lower level of the midbrain. Significantly, the bilateral CPMIs presented with a characteristic “V-shaped” appearance in the axial MRI. All patients presented with bilateral cerebellar dysfunction which included dysarthric speech, truncal or gait ataxia and four-limb ataxia. In addition, diplopia and internuclear ophthalmoplegia were frequently encountered in CPMI. Five (41.7%) patients were classified with large artery atherosclerosis, four (33.3%) with small vessel disease, two (16.7%) with cardiogenic embolism, and one (8.3%) with undetermined etiology. CPMI is a rare cerebrovascular disease that destroys the Wernekink commissure, medial longitudinal fasciculi and other adjacent structures. It is characterized by bilateral cerebellar ataxia and eye movement disorders, mainly internuclear ophthalmoplegia. A distinct “V-shaped” radiological feature can be seen in bilateral CPMI patients. The primary mechanisms of unilateral CPMI involve small vessel disease. The underlying stroke mechanisms of bilateral CPMI are either large artery atherosclerosis disease or cardiac embolism.
Mouse model induced by azoxymethane (AOM) and dextran sodium sulfate (DSS) is generally accepted as an ideal object to study on the carcinogenesis mechanisms of human colorectal cancer (CRC). The ...genomic responses to the AOM/DSS treatment in mouse that possibly lead to elucidation of CRC pathological mechanism are still poorly understood. For the first time, we investigated the cancer genome landscape of AOM/DSS mouse model by exome sequencing, to testify its molecular faithfulness to human CRC. Of 14 neoplastic samples, 7575 somatic variants were identified, which resulted in 2507 mutant genes and exhibited a large diversity in both colorectal aberrant crypt foci (ACF) and tumors even those tissues that were gained from the similar morphology or same treatment period. Cross-species comparison of the somatic variants demonstrated the totally different patterns of variable sites, mutant genes and perturbed pathways between mouse and human CRC. We therefore come to a conclusion that the tumorigenesis at genomic level in AOM/DSS model may not be properly comparable with that in human CRC, and the molecular mechanism elicited from this animal model should be carefully evaluated.
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