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1.
Artigo em Inglês | MEDLINE | ID: mdl-33146999

RESUMO

Compared to three-dimensional (3D) organic-inorganic hybrid perovskites, two-dimensional (2D) ones possess great possibilities to realize stable cost-effective perovskite solar cells (PSCs). However, studies indicated that PSCs with 2D perovskites exhibited poor power conversion efficiencies (PCEs). In this study, we report novel propargylamine cation (PPA+)-based quasi-2D perovskites. PPA+ employed as an organic spacer is for enhancing charge-carrier transport of quasi-2D (PPA)2(CH3NH3)2Pb3I10 thin films, consequently boosting PCEs of PSCs. To further boost PCEs of PSCs with quasi-2D (PPA)2(CH3NH3)2Pb3I10 thin films, a quasi-2D (PPA)2(CH3NH3)2Pb3I10 thin film is processed with Pb(SCN)2 additives. Systematical studies indicate that the quasi-2D (PPA)2(CH3NH3)2Pb3I10 thin film processed with Pb(SCN)2 additives exhibits superior film morphology and crystallinity, larger crystals, reduced nonradiative charge-carrier recombination, and enhanced and balanced charge-carrier mobilities compared to the pristine quasi-2D (PPA)2(CH3NH3)2Pb3I10 thin film. As a result, PSCs with the quasi-2D (PPA)2(CH3NH3)2Pb3I10 thin film processed with Pb(SCN)2 additives exhibit a PCE of 15.20%, which is an over 25% enhancement compared to those (12.16%) with a pristine quasi-2D (PPA)2(CH3NH3)2Pb3I10 thin film. In addition, PSCs with the quasi-2D (PPA)2(CH3NH3)2Pb3I10 thin film processed with Pb(SCN)2 additives possess dramatically suppressed photocurrent hysteresis and significantly boosted stability. All these results indicate that we have developed a facile way to synthesize novel 2D perovskite thin films for realizing stable and efficient PSCs with dramatically suppressed photocurrent hysteresis.

2.
Allergy ; 2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33175399

RESUMO

BACKGROUND: Asthma is highly heterogeneous, and severity evaluation is key to asthma management. DNA methylation (DNAm) contributes to asthma pathogenesis. This study aimed to identify nasal epithelial DNAm differences between severe and nonsevere asthmatic children and evaluate the impact of environmental exposures. METHODS: Thirty-three nonsevere and 22 severe asthmatic African American children were included in an epigenome-wide association study. Genome-wide nasal epithelial DNAm and gene expression were measured. CpG sites associated with asthma severity and environmental exposures and predictive of severe asthma were identified. DNAm was correlated with gene expression. Enrichment for transcription factor (TF) binding sites or histone modifications surrounding DNAm differences were determined. RESULTS: We identified 816 differentially methylated CpG positions (DMPs) and 10 differentially methylated regions (DMRs) associated with asthma severity. Three DMPs exhibited discriminatory ability for severe asthma. Intriguingly, six DMPs were simultaneously associated with asthma, allergic asthma, total IgE, environmental IgE, and FeNO in an independent cohort of children. Twenty-seven DMPs were associated with traffic-related air pollution or secondhand smoke. DNAm at 22 DMPs was altered by diesel particles or allergen in human bronchial epithelial cells. DNAm levels at 39 DMPs were correlated with mRNA expression. Proximal to 816 DMPs, three histone marks and several TFs involved in asthma pathogenesis were enriched. CONCLUSIONS: Significant differences in nasal epithelial DNAm were observed between nonsevere and severe asthma in African American children, a subset of which may be useful to predict disease severity. These CpG sites are subjected to the influences of environmental exposures and may regulate gene expression.

3.
Commun Biol ; 3(1): 675, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33188264

RESUMO

ATAC-seq (Assay for Transposase-Accessible Chromatin with high-throughput sequencing) provides an efficient way to analyze nucleosome-free regions and has been applied widely to identify transcription factor footprints. Both applications rely on the accurate quantification of insertion events of the hyperactive transposase Tn5. However, due to the presence of the PCR amplification, it is impossible to accurately distinguish independently generated identical Tn5 insertion events from PCR duplicates using the standard ATAC-seq technique. Removing PCR duplicates based on mapping coordinates introduces increasing bias towards highly accessible chromatin regions. To overcome this limitation, we establish a UMI-ATAC-seq technique by incorporating unique molecular identifiers (UMIs) into standard ATAC-seq procedures. UMI-ATAC-seq can rescue about 20% of reads that are mistaken as PCR duplicates in standard ATAC-seq in our study. We demonstrate that UMI-ATAC-seq could more accurately quantify chromatin accessibility and significantly improve the sensitivity of identifying transcription factor footprints. An analytic pipeline is developed to facilitate the application of UMI-ATAC-seq, and it is available at https://github.com/tzhu-bio/UMI-ATAC-seq .

4.
Carbohydr Res ; : 108196, 2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33243427

RESUMO

Brucellosis is a highly infectious zoonotic disease caused by Brucella. It is necessary to control and eliminate brucellosis. The cell wall O-polysaccharides of pathogenic Brucella species are homopolymers of the rare sugar 4,6-dideoxy-4-formamido-α-d-mannopyranose. Herein, one neoglycoconjugate was successfully synthesized based on disaccharide [Rha4NFo(1 â†’ 2)Rha4NFo] as epitope. Disaccharide specific antibodies were detected by ELISA and the immune protective effect was further evaluated with PBS as control. The result showed that the synthetic neoglycoconjugate can produce moderate immune responses in mice and significantly decreased splenic Brucella M5 burden comparing with control group. The chemically defined antigen identified the A antigenic determinant and provided a structural basis for understanding the fine specificity of polyclonal antibodies that bind the A antigen. The neoglycoconjugate shows the potential in detection reagent or vaccine development for brucellosis.

5.
Aging (Albany NY) ; 12(21): 21597-21612, 2020 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-33216733

RESUMO

Breast cancer is one of the most lethal malignancies among women, and understanding the effects of host immunity on disease progression offers the potential to improve immunotherapies against it. Here, we constructed an immunity-related gene (IRG)-based prognostic signature to stratify breast cancer patients and predict their survival. We identified differentially-expressed genes by analyzing the breast cancer transcriptome data from The Cancer Genome Atlas. Univariate Cox regression revealed 179 survival-correlated IRGs, 12 of which we used to construct an immunity-based prognostic signature that stratified breast cancer patients into high- and low-risk groups. The signature was an independent predictor for survival and was validated in an independent dataset. We also investigated the correlations between our prognostic signature and immune infiltrates and found that signature-derived risk scores correlated negatively with infiltration of B cells, CD4+ T cells, CD8+ T cells, neutrophils and dendritic cells. Our results show that the proposed prognostic signature reflects the tumor immune microenvironment, which makes it a potential indicator for survival that warrants further research to assess its clinical utility.

6.
Signal Transduct Target Ther ; 5(1): 216, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33154351

RESUMO

Emerging evidence suggests that Toll-like receptors (TLRs) ligands pretreatment may play a vital role in the progress of myocardial ischemia/reperfusion (I/R) injury. As the ligand of TLR3, polyinosinic-polycytidylic acid (poly(I:C)), a synthetic double-stranded RNA, whether its preconditioning can exhibit a cardioprotective phenotype remains unknown. Here, we report the protective effect of poly(I:C) pretreatment in acute myocardial I/R injury by activating TLR3/PI3K/Akt signaling pathway. Poly(I:C) pretreatment leads to a significant reduction of infarct size, improvement of cardiac function, and downregulation of inflammatory cytokines and apoptotic molecules compared with controls. Subsequently, our data demonstrate that phosphorylation of TLR3 tyrosine residue and its interaction with PI3K is enhanced, and protein levels of phospho-PI3K and phospho-Akt are both increased after poly(I:C) pretreatment, while knock out of TLR3 suppresses the cardioprotection of poly(I:C) preconditioning through a decreased activation of PI3K/Akt signaling. Moreover, inhibition of p85 PI3K by the administration of LY294002 in vivo and knockdown of Akt by siRNA in vitro significantly abolish poly(I:C) preconditioning-induced cardioprotective effect. In conclusion, our results reveal that poly(I:C) preconditioning exhibits essential protection in myocardial I/R injury via its modulation of TLR3, and the downstream PI3K/Akt signaling, which may provide a potential pharmacologic target for perioperative cardioprotection.

7.
J Hazard Mater ; 404(Pt A): 123936, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-33070004

RESUMO

In this paper, the simultaneous removal of SO2 and NOx catalyzed by Fe-Mo mixed oxides at varying Mo/Fe atomic ratios was reported for the first time with the aim of reducing H2O2 consumption and elucidating the roles of Fe and Mo species in the catalytic process. Fe-Mo mixed oxides with varying Mo/Fe atomic ratios were synthesized and the catalytic performances were systematically studied. The catalyst with Mo/Fe atomic ratio of 2.0 exhibited the highest activity, with which removal efficiencies of 89.4 % for NOx and 100 % for SO2 can be attained at extremely low H2O2 dosage. Products analysis revealed that SO2 was mainly removed via wet scrubber, while the adequate oxidation resulting from OH radicals was the prerequisite for NOx removal. The redox pair of Fe2+/Fe3+ played a significant role in decomposing H2O2, while Mo species had double effect on catalytic activity. Higher Mo content resulted in abundant oxygen vacancies and stronger surface acidity, which favored OH formation. However, the excessive Mo content involved severe surface Mo enrichment and remarkably reduced the active sites of Fe species. The H2O2/Fe-Mo catalyst system showed excellent stability and had a promising prospect for simultaneously removing SO2 and NOx in coal-fired flue gas.

8.
BMC Genomics ; 21(1): 711, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33054712

RESUMO

BACKGROUND: Genes are regulated by various types of regulators and most of them are still unknown or unobserved. Current gene regulatory networks (GRNs) reverse engineering methods often neglect the unknown regulators and infer regulatory relationships in a local and sub-optimal manner. RESULTS: This paper proposes a global GRNs inference framework based on dictionary learning, named dlGRN. The method intends to learn atomic regulators (ARs) from gene expression data using a modified dictionary learning (DL) algorithm, which reflects the whole gene regulatory system, and predicts the regulation between a known regulator and a target gene in a global regression way. The modified DL algorithm fits the scale-free property of biological network, rendering dlGRN intrinsically discern direct and indirect regulations. CONCLUSIONS: Extensive experimental results on simulation and real-world data demonstrate the effectiveness and efficiency of dlGRN in reverse engineering GRNs. A novel predicted transcription regulation between a TF TFAP2C and an oncogene EGFR was experimentally verified in lung cancer cells. Furthermore, the real application reveals the prevalence of DNA methylation regulation in gene regulatory system. dlGRN can be a standalone tool for GRN inference for its globalization and robustness.

9.
Int J Chron Obstruct Pulmon Dis ; 15: 2653-2662, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33122903

RESUMO

Background and Purpose: Recently, fine particulate matter (PM2.5) was identified as the main exposure risk for COPD, and inflammation is central to the development of COPD. In this study, we investigated whether PM2.5 can induce the secretion of interleukin-6 (IL-6), IL-8 and IL-1ß in human bronchial epithelial cells (HBECs) in vitro via the wingless-related integration site 5A (Wnt5a)/receptor tyrosine kinase-like orphan receptor 2 (Ror2) signaling. Methods: The expression of Wnt5a and Ror2 was assessed by immunohistochemistry in motor vehicle exhaust (MVE)-induced Sprague-Dawley rats. HBECs were transfected with small interfering RNA (siRNA) targeting Wnt5a or Ror2 and subsequently stimulated with PM2.5.The secretion of IL-6, IL-8 and IL-1ß was assessed by ELISAs, and the expression of Wnt5a/Ror2 signaling were assessed by RT-PCR and Western blotting. Results: Both Wnt5a and Ror2 protein were increased in the lung of MVE-induced rats. HBECs exposed to PM2.5 for 24 h significantly upregulated Wnt5a and Ror2 expression and subsequently promoted the nuclear translocation of NF-κB, which increased the production of IL-1ß, IL-6 and IL-8. Wnt5a siRNA prevented these outcomes. Wnt5a antagonist (BOX5) also prevented inflammatory effects. Furthermore, Ror2 siRNA blocked the NF-κB activity and inhibited the release of IL-6, IL-8 and IL-1ß from PM2.5-exposed HBECs. Conclusion: PM2.5 induces the secretion of IL-6, IL-8 and IL-1ß in HBECs via the Wnt5a/Ror2 signaling, demonstrating a novel mechanism for PM2.5-associated airway inflammation.

10.
Cell Signal ; 76: 109800, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33011290

RESUMO

NK1.1- CD4+ NKG2D+ T cells are a subpopulation of regulatory T cells that downregulate the functions of CD4+ T, CD8+ T, natural killer (NK) cells, and macrophages through TGF-ß1 production. Early growth response genes 2 (Egr2) and 3 (Egr3) maintain immune homeostasis by modulating T lymphocyte development, inhibiting effector T cell function, and promoting the induction of regulatory T cells. Whether Egr2 and Egr3 directly regulate TGF-ß1 transcription in NK1.1- CD4+ NKG2D+ T cells remains elusive. The expression levels of Egr2 and Egr3 were higher in NK1.1- CD4+ NKG2D+ T cells than in NK1.1- CD4+ NKG2D- T cells. Egr2 and Egr3 expression were remarkably increased after stimulating NK1.1- CD4+ NKG2D+ T cells with sRAE or α-CD3/sRAE. The ectopic expression of Egr2 or Egr3 resulted in the enhancement of TGF-ß1 expression, while knockdown of Egr2 or Egr3 led to the decreased expression of TGF-ß1 in NK1.1- CD4+ NKG2D+ T cells. Egr2 and Egr3 directly bound with the TGF-ß1 promoter as demonstrated by the electrophoretic mobility shift assay and dual-luciferase gene reporter assay. Furthermore, the Egr2 and Egr3 expression of NK1.1- CD4+ NKG2D+ T cells could be induced by the AP-1 and NF-κB transcriptional factors, but had no involvement with the activation of NF-AT and STAT3. In conclusion, Egr2 and Egr3 induced by AP-1 and NF-κB directly initiate TGF-ß1 transcription in NK1.1- CD4+ NKG2D+ T cells. This study indicates that manipulating Egr2 and Egr3 expression would potentiate or alleviate the regulatory function of NK1.1- CD4+ NKG2D+ T cells and this strategy could be used in the therapy for patients with autoimmune diseases or tumor.

12.
Chin Med J (Engl) ; 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-33009026

RESUMO

BACKGROUND: Mounting evidence, consistent with our previous study, showed that γ-aminobutyric acid type A receptor (GABAAR) played an indispensable role in airway inflammation and mucus hypersecretion in asthma. Monocyte chemotactic protein-inducing protein 1 (MCPIP1) was a key negative regulator of inflammation. Recent studies showed that inflammation was largely suppressed by enhanced MCPIP1 expression in many inflammatory diseases. However, the role and potential mechanism of MCPIP1 in airway inflammation and mucus hypersecretion in asthma were still not well studied. This study was to explore the role of MCPIP1 in asthmatic airway inflammation and mucus hypersecretion in both mice and BEAS-2B cells, and its potential mechanism. METHODS: In vivo, mice were sensitized and challenged by ovalbumin (OVA) to induce asthma. Airway inflammation and mucus secretion were analyzed. In vitro, BEAS-2B cells were chosen. Interleukin (IL)-13 was used to stimulate inflammation and mucus hypersecretion in cells. MCPIP1 Lentiviral vector (LA-MCPIP1) and plasmid-MCPIP1 were used to up-regulate MCPIP1 in lung and cells, respectively. MCP-1, thymic stromal lymphopoietin (TSLP), mucin 5AC (MUC5AC), MCPIP1, and GABAARß2 expressions were measured in both lung and BEAS-2B cells. Immunofluorescence staining was performed to observe the expression of GABAARß2 in cells. RESULTS: MCPIP1 was up-regulated by LA-MCPIP1 (P < 0.001) and plasmid-MCPIP1 (P < 0.001) in lung and cells, respectively. OVA-induced airway inflammation and mucus hypersecretion, OVA-enhanced MCP-1, TSLP, MUC5AC, and GABAARß2 expressions, and OVA-reduced MCPIP1 were significantly blunted by LA-MCPIP1 in mice (all P < 0.001). IL-13-enhanced MCP-1, TSLP, MUC5AC, and GABAARß2 expressions, and IL-13-reduced MCPIP1 were markedly abrogated by plasmid-MCPIP1 in BEAS-2B cells (all P < 0.001). CONCLUSION: The results of this study suggested that OVA and IL-13-induced airway inflammation and mucus hypersecretion were negatively regulated by MCPIP1 in both lung and BEAS-2B cells, involving GABAAR signaling pathway.

13.
Mol Cancer Res ; 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33037085

RESUMO

It is commonly accepted that cellular protein levels are primarily determined by mRNA levels. However, discordance between protein and mRNA expression has been implicated in many pathological conditions including oncogenesis. The mechanisms involved in this discordance are complicated and far from understood. In this study, it was observed that the expression levels of PCBP2 mRNA and protein were diametric in breast normal and cancer cell lines, paraffin-embedded and fresh tissue specimens, consistent with data from The Cancer Genome Atlas (TCGA) and the Clinical Proteomic Tumor Analysis Consortium (CPTAC). Moreover, PCBP2 protein expression was significantly associated with disease progression and poor outcome in patients with breast cancer. Depletion of PCBP2 protein inhibited cell proliferation, colony formation, migration, invasion and in vivo tumor growth and metastasis. Forced expression of PCBP2 exhibited the opposite effect. Mechanistically, it was demonstrated that PCBP2 3'UTR was subject to alternative splicing and polyadenylation (APA) in breast cancer tissues and cell lines. Non-full-length 3'UTR PCBP2 transcripts yielded more protein than the full-length 3'UTR transcripts and enhanced the oncogenic and metastatic capacities of human breast cancer cells. Furthermore, UFD1 and NT5E were identified as genes downstream of PCBP2. PCBP2 promoted oncogenicity of breast cancer cells via upregulation of the expression of UFD1 and NT5E by direct binding to their 3'UTR-B portions. Implications: Findings demonstrate that APA of PCBP2 3'UTR contributes to its increased expression with subsequent promotion of breast cancer progression by regulating UFD1 and NT5E.

14.
New Phytol ; 2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33129229

RESUMO

Improving yield is a primary mission for cotton (Gossypium hirsutum L.) breeders; development of cultivars with suitable architecture for high planting density (HPDA) can increase yield per unit area. We characterized a natural cotton mutant, AiSheng98 (AS98), which exhibits shorter height, shorter branch length, and more acute branch angle than wild type. A copy number variant at the HPDA locus on Chromosome D12 (HPDA-D12), encoding a dehydration-responsive element-binding (DREB) transcription factor, GhDREB1B, strongly affects plant architecture in the AS98 mutant. We found an association between a tandem duplication of a ~13.5 kb segment in HPDA-D12 and elevated GhDREB1B expression resulting in the AS98 mutant phenotype. GhDREB1B overexpression confers a significant decrease in plant height and branch length, and reduced branch angle. Our results suggest that fine-tuning GhDREB1B expression may be a viable engineering strategy for modification of plant architecture favorable to high planting density in cotton.

15.
Artigo em Inglês | MEDLINE | ID: mdl-33112751

RESUMO

In order to quickly discover the low-dimensional representation of high-dimensional noisy data in online environments, we transform the linear dimensionality reduction problem into the problem of learning the bases of linear feature subspaces. Based on that, we propose a fast and robust dimensionality reduction framework for incremental subspace learning named evolutionary orthogonal component analysis (EOCA). By setting adaptive thresholds to automatically determine the target dimensionality, the proposed method extracts the orthogonal subspace bases of data incrementally to realize dimensionality reduction and avoids complex computations. Besides, EOCA can merge two learned subspaces that are represented by their orthonormal bases to a new one to eliminate the outlier effects, and the new subspace is proved to be unique. Extensive experiments and analysis demonstrate that EOCA is fast and achieves competitive results, especially for noisy data.

16.
Int J Mol Sci ; 21(18)2020 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-32899571

RESUMO

Allotetraploid cotton (Gossypium hirsutum and Gossypium barbadense) are cultivated worldwide for its white fiber. For centuries, conventional breeding approaches increase cotton yield at the cost of extensive erosion of natural genetic variability. Sea Island cotton (G. barbadense) is known for its superior fiber quality, but show poor adaptability as compared to Upland cotton. Here, in this study, we use ethylmethanesulfonate (EMS) as a mutagenic agent to induce genome-wide point mutations to improve the current germplasm resources of Sea Island cotton and develop diverse breeding lines with improved adaptability and excellent economic traits. We determined the optimal EMS experimental procedure suitable for construction of cotton mutant library. At M6 generation, mutant library comprised of lines with distinguished phenotypes of the plant architecture, leaf, flower, boll, and fiber. Genome-wide analysis of SNP distribution and density in yellow leaf mutant reflected the better quality of mutant library. Reduced photosynthetic efficiency and transmission electron microscopy of yellow leaf mutants revealed the effect of induced mutations at physiological and cellular level. Our mutant collection will serve as the valuable resource for basic research on cotton functional genomics, as well as cotton breeding.

17.
Paediatr Anaesth ; 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32965066

RESUMO

Safe and effective techniques for propofol total intravenous anesthesia (TIVA) in infants are not well imbedded into clinical practice, resulting in practitioner unfamiliarity and potential for over- and under-dosing. In this education article, we describe our approach to TIVA dosing in infants and toddlers (birth to 36 months) which combines the use of pharmacokinetic models with EEG multi-parameter analysis. Pharmacokinetic models describe propofol and remifentanil effect site concentrations (Ce) over time in different age groups for a given dosing regimen. These models display substantial biological variability between individuals within age groups, impeding their application to clinical practice. Nevertheless, they reveal that younger infants require a higher propofol loading dose, a lower propofol maintenance dose, and a higher remifentanil dose compared with older infants. Proprietary EEG indices (eg, Bispectral Index) can serve as a biomarker of propofol Ce in adults and children to guide dosing to the individual patient; however, they are not recommended for infants as their validity remains uncertain this population. In our experience, EEG waveforms and processed parameters can reflect propofol Ce in infants, reflected by spectral edge frequency (SEF), density spectral array (DSA), and waveform patterns. In our practice, we use a "lookup table" of age-based dosing regimens or target-controlled infusion (TCI) based on the pharmacokinetic models to deliver a target propofol Ce and co-administer remifentanil and/or regional technique for analgesia. We analyze Electroencephalogram (EEG) waveforms, SEF, and DSA to adjust the propofol dose or TCI target concentration to the individual infant. EEG analysis mitigates against biological variability inherent in the pharmacokinetic models and has improved our experience with TIVA for infants.

18.
Int J Comput Assist Radiol Surg ; 15(12): 1951-1962, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32986142

RESUMO

PURPOSE: Bone age assessment is not only an important means of assessing maturity of adolescents, but also plays an indispensable role in the fields of orthodontics, kinematics, pediatrics, forensic science, etc. Most studies, however, do not take into account the impact of background noise on the results of the assessment. In order to obtain accurate bone age, this paper presents an automatic assessment method, for bone age based on deep convolutional neural networks. METHOD: Our method was divided into two phases. In the image segmentation stage, the segmentation network U-Net was used to acquire the mask image which was then compared with the original image to obtain the hand bone portion after removing the background interference. For the classification phase, in order to further improve the evaluation performance, an attention mechanism was added on the basis of Visual Geometry Group Network (VGGNet). Attention mechanisms can help the model invest more resources in important areas of the hand bone. RESULT: The assessment model was tested on the RSNA2017 Pediatric Bone Age dataset. The results show that our adjusted model outperforms the VGGNet. The mean absolute error can reach 9.997 months, which outperforms other common methods for bone age assessment. CONCLUSION: We explored the establishment of an automated bone age assessment method based on deep learning. This method can efficiently eliminate the influence of background interference on bone age evaluation, improve the accuracy of bone age evaluation, provide important reference value for bone age determination, and can aid in the prevention of adolescent growth and development diseases.

19.
Pathol Res Pract ; 216(11): 153193, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32927306

RESUMO

Phlebosclerotic colitis (PC) is a rare chronic ischemic colitis caused by venous reflux disorder. It is also called idiopathic mesenteric phlebosclerosis (IMP) due to unknown etiology. The disease is characterized by sclerosis of mesenteric vein and its branches as well as fibrosis, hyaline degeneration, calcification, thickening of colon wall. CT images show linear calcification in the colon mucosa as well as mesenteric vein and its branches. Endoscopy shows purple-blue mucosa with multiple erosion and ulceration. Microscopically, the colon mucosa shows fibrosis, hyaline degeneration and extensive thickening. The most characteristic lesion is fibrosis and calcification of the vessels especially the veins. Arteries in all layers of colon are also involved, but the injury is significant mild and less. We collected 10 confirmed patients from 2012 to 2019 in our hospital, studied their clinical histories in detail, summarized typical changes of CT images, endoscopic images and pathological sections, and made a detail follow-up. In addition to typical pathological changes, we also found that gardenia or its metabolites may be the pathogenic factor. Probablely, geniposide which is metabolized to genipin by ß-glucosidase of colon flora in proximal colon, results in venous sclerosis. PC is occult onset and irreversible without special symptoms in the early stage, but it will also be stable after removing the pathogenic ingredient. Most of patients may be "cured" by appropriate conservative medication and stopping drinking. Contrary, inappropriate surgery may "trigger" the acute ischemia which results in obstruction rapidly. We hope our colleagues pay attention to the unique lesion and make early diagnosis and treatment.

20.
Eur J Med Chem ; 208: 112776, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32896759

RESUMO

A set of fluorinated sialyl-T derivatives were efficiently synthesized using one-pot multi-enzyme (OPME) chemoenzymatic approach. The P. multocida α2-3-sialyltransferase (PmST1) involved in the synthesis showed extremely flexible donor and acceptor substrate specificities. These sialosides have been successfully investigated with stability towards Clostridium perfringens sialidase substrate specificity assay using 1H NMR spectroscopy. Hydrolysis studies monitored by 1H NMR clearly demonstrated that the fluorine substitution obviously reduced hydrolysis rate of Clostridium perfringens sialidase. To further investigate the fluorine influence, structure-dependent variation of sialoside-lectin binding was observed for MAL and different sialoside-immobilized surfaces. Subtle changes on the ligand of carbohydrate-binding protein were distinguished by SPR. These fluorinated sialyl-T derivatives obtained are valuable probes for further biological studies or antitumor drug design.

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