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1.
J Colloid Interface Sci ; 613: 276-284, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35042028

RESUMO

Fabricating high-efficiency catalysts of Pt nanoparticles coupled with single-atom sites (MNC) attracts intensive attention to accelerate the oxygen reduction reaction (ORR). Here we rationally design the low-Pt hybrid catalyst containing fine Pt nanoparticles coupled with Co-Nx moieties via a microwave-assisted heating process. The well-dispersed Pt nanoparticles are anchored by CoNC supports because of the metal-support interaction. Furthermore, the Co-Nx moiety acts as an electron donor to regulate the electronic structure of Pt through the electron synergistic effect, moderating the adsorption energy of oxygen intermediates on Pt sites, and then increasing the intrinsic activity of Pt. In addition, the overflow effect from CoNC to Pt facilitates a nearly four-electron process and enhances the kinetics of ORR. In acid media, the optimized 10% Pt/CoNC hybrid catalysts with Pt nanoparticles size (2.18 nm) exhibit improved ORR activity and robust durability, delivering a half-wave potential (E1/2) of 0.886 V and negligible loss after accelerated durability test, exceeding the best-in-class commercial Pt/C. The finding of the synergy between CoNC supports and Pt nanoparticles offers a novel ideation to construct various low-loading Pt-based hybrid catalysts.

2.
Small ; : e2106683, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35038223

RESUMO

Conventional synthesis of carbon dots (CDs) mostly involves a hydrothermal or solvent-thermal reaction which needs relatively high temperature and pressure. In this work, ionic liquid is used to assist in fast synthesizing CDs with an ultrahigh photoluminescent quantum yield (98.5%) by heating at a low temperature (≤100 °C) and at atmospheric pressure. In addition, through this approach, tunable multicolor emissive CDs can be successfully achieved and used for preparing high-performance white light-emitting diodes. Theoretical computation proves that the activity of synthesis reaction can be significantly enhanced by ionic liquids. Density functional theory calculation reveals that the size and graphite nitrogen ratios of CDs have an effect on bandgap reduction, resulting in a redshift of the emission, which is in good agreement with the experimental results. This simple and promising approach for fast synthesis of tunable emissive CDs using ionic liquid affords the facilitation of CDs-based luminescent materials for fast manufacturing of functional devices.

3.
Nanoscale ; 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35006232

RESUMO

The oily wastewater and oil spill caused by oil leakage accidents are extremely harmful to human health and the environment. Thus, it is very important to exploit superhydrophobic separation materials and technologies for oil/water separation and oil spill cleanup. In this study, using the 1,4-conjugate addition reaction between polyethyleneimine (PEI) and 3-(trimethoxysilyl)propyl acrylate (TMSPA), hydrolysis condensation reaction of TMSPA and dodecyltrimethoxysilane (DTMS) jointly connecting to the surface of hydrophilic silica nanoparticles, and hydrogen bond interaction of the residual amino group on the surface of PEI, covalently-crosslinked rough network structures were constructed on fabric surfaces, which endow PEI/TMSPA/SiO2/DTMS fabrics with excellent superhydrophobic properties. The obtained superhydrophobic fabric not only showed excellent heat resistance and excellent stability to acid, alkali, salt and organic solvents, but also showed good mechanical stability to tape stripping and washing tests. The superhydrophobic, superoleophilic properties and porous structure of the modified fabric make it have excellent oil/water separation efficiency (98.49% after 18 cycles) and oil spill cleanup efficiency (95.35% after 9 cycles). This superhydrophobic PEI/TMSPA/SiO2/DTMS fabric has characteristics of simple preparation, environmental friendliness and scale-up, which makes it a very promising separation material for actual oil/water separation and oil spill cleanup.

4.
Chem Commun (Camb) ; 2022 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-35015000

RESUMO

A facile synthetic approach to prepare environmentally friendly white fluorescent carbon dots (CDs)/ZnO quantum dots (QDs) composites through electrostatic force is described. This method can be used for fabrication of high-performance white light-emitting diodes (WLEDs). The fluorescence emission spectra of WLED devices covered a range from 425 nm to 750 nm. WLEDs had a CIE chromaticity coordinate of (0.30, 0.34) and a color temperature of 7093 K.

5.
Dev Comp Immunol ; 126: 104264, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34551359

RESUMO

The ß-defensins are important components of the vertebrate innate immune system. While mammalian ß-defensins have wide-ranging antibacterial and immunomodulatory activities, those of amphibians remain largely uncharacterised. In this study, ß-defensin cDNA was identified from the skin transcriptome of the Chinese spiny frog Quasipaa spinosa. This ß-defensin (QS-BD) consists of a signal and a mature peptide. Sequence alignments with other amphibian ß-defensins showed conservation of the functional mature peptide and that its closest relative is ß-defensin from Zhangixalus puerensis. Synthetic QS-BD showed antibacterial activity against Vibrio vulnificus, Vibrio harveyi, Streptococcus iniae, and Aeromonas hydrophila. QS-BD showed bactericidal activity by destroying the cell membrane integrity, but did not hydrolyse genomic DNA. QS-BD treatment promoted respiratory bursts and upregulated the expression of interleukin-1ß and tumour necrosis factor-α in the murine leukemic monocyte/macrophage cell line RAW264.7. This is the first demonstration of immunomodulatory activity by an amphibian ß-defensin.

6.
Zhongguo Zhong Yao Za Zhi ; 46(21): 5585-5592, 2021 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-34951210

RESUMO

Intestinal microecology is an important defense system in the human body. The intestinal flora is the core micro-ecosystem in the human intestine. It has a symbiotic relationship with the overall functions of the body. It has strong metabolic activity to maintain the normal functioning of the body and resist the invasion of various viral antigens in the body. Playing a protective function,the imbalanced intestinal microecology can cause various diseases. Polysaccharides can be extracted from a wide range of sources and have low toxicity and side effects. They have attracted wide attention because of their anti-tumor, anti-oxidant, anti-inflammatory and other biological activities. Studies have demonstrated that polysaccharides can regulate intestinal microecological disorders. According to the studies in recent years, this review summarizes that polysaccharides mainly modulate intestinal microecological disorders through regulating the composition of intestinal flora, improving the metabolism of the flora, and repairing the intestinal tract barrier. On the basis of these mechanisms of action, this paper elaborates the anti-tumor, immunomodulatory, and anti-inflammatory activities of polysaccharides. This paper can provide reference for the future research on the intestinal microecology-regulating mechanism and biological activities of polysaccharides.


Assuntos
Ecossistema , Microbioma Gastrointestinal , Anti-Inflamatórios , Humanos , Intestinos , Polissacarídeos/farmacologia
7.
Front Pediatr ; 9: 764797, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34956979

RESUMO

Malignant atrophic papulosis (MAP) is a life-threatening vasculopathy affecting the skin, gastrointestinal tract, central nervous system, pleural membrane, and pericardium. MAP carries a poor prognosis primarily because of its systemic involvement. It is extremely rare in children. Herein, we report a pediatric case of MAP with small bowel perforation and anticardiolipin antibody positivity.

8.
Curr Microbiol ; 79(1): 8, 2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34905098

RESUMO

A novel strain, wg2T, was isolated from activated sludge obtained from wastewater treatment plant in Shandong province, China. The bacterium was Gram-strain-negative, aerobic, rod-shaped, non-flagellated and non-gliding. This bacterium was characterized to determine its taxonomic position using the polyphasic approach. Strain wg2T grew at 25-45 °C (optimum, 30 °C), at salinities of 0-7.0% (w/v) NaCl (optimum, 0-2.0%) and at pH 7-9 (optimum, pH 7.0). Phylogenetic analysis based on 16S rRNA gene sequence showed that strain wg2T clustered with species of genus Paracoccus and shares high similarities with Paracoccus sediminis DSM 26170 T (98.1%) and Paracoccus fontiphilus MVW-1 T (97.7%), respectively. The genome size of strain wg2T was 3.93 Mbp and the DNA G + C content was 66.05%. The dDDH values and ANI between strain wg2T and each of reference strains P. sediminis DSM 26170 T, P. fontiphilus MVW-1 T and P. denitrificans DSM 413 T were 18.3, 12.5, 24.5% and 85.3, 87.0, 78.4%, respectively. The major respiratory quinone was found to be Q-10 and the major fatty acid was C18:1 ω7c. The polar lipids consisted of aminoglycolipid (AGL), phosphatidylcholine (PC), glycolipid (GL), phosphatidylserine (PS), phosphatidylglycerol phosphate (PGP), aminophospholipids (APL). Combining above descriptions, strain wg2T should represent a novel species of genus Paracoccus, for which the name Paracoccus shandongensis sp. nov., is proposed. The type strain is wg2T (= KCTC 72862 T = CCTCC AB 2019401 T).


Assuntos
Paracoccus , Esgotos , Técnicas de Tipagem Bacteriana , China , DNA Bacteriano/genética , Ácidos Graxos/análise , Paracoccus/genética , Fosfolipídeos/análise , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
9.
Zhonghua Nan Ke Xue ; 27(8): 733-737, 2021 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-34914247

RESUMO

Objective: To evaluate the efficacy and safety of Lingze Tablets in the treatment of BPH with kidney deficiency, blood stasis and dampness resistance. METHODS: Totally 235 eligible BPH patients, aged 50-80 years and meeting the inclusion criteria, were enrolled and treated with Lingze Tablets orally, 4 tablets per time, tid. Before and after an 8-week course of medication, IPSS, quality of life (QOL) and TCM syndromes scores were obtained from the patients. RESULTS: Of the total number of patients, 211 completed the whole course of treatment. Compared with the baseline, the IPSS was dramatically reduced after 4 and 8 weeks of medication (18.28 ± 5.29 vs 12.82 ± 4.66 and 9.23 ± 4.21, P < 0.01), and so were the QOL scores (6.44 ± 1.99 vs 4.95 ± 1.64 and 3.16 ± 1.53, P < 0.01) and TCM syndromes scores (17.49 ± 5.30 vs 12.45 ± 3.74 and 9.17 ± 3.24, P < 0.01). The incidence rates of adverse events and drug-related adverse reactions were 15.2% and 1.9%, respectively, and no organ function impairment was observed. CONCLUSIONS: Lingze Tablets are definitely effective and safe for the treatment of BPH with kidney deficiency, blood stasis and dampness resistance.


Assuntos
Hiperplasia Prostática , Qualidade de Vida , Humanos , Rim , Comprimidos
10.
Front Pharmacol ; 12: 766737, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34744745

RESUMO

Mori Fructus polysaccharides (MFP) are macromolecules extracted from Mori Fructus (MF), which has the biological activity of anti-liver damage. Our group found that MFP maybe down regulate the serum triglyceride level in mice with alcohol-induced liver damage, suggesting that MFP can regulate lipid metabolism, but its specific mechanism is still not clear. Fifty SPF-ICR male mice weighing 18-22 g were randomly divided into five groups, blank group, model group, bifendate group, MFPA1 group and MFPB1 group. The blood and liver tissues were taken from mice for nontargeted lipidomic analysis and histopathological examination after 7 day's treatment. The histopathological changes indicated that the normal liver cells were intact and regular, with orderly arrangement and distinct cell boundaries; the liver of model mice showed inflammatory infiltration, ballooning degeneration in the cells and small lipid drops; the liver of mice in the bifendate, MFPA1 and MFPB1 groups showed similar symptoms to those of model mice, but the lesions were less severe and the ballooning degeneration were reduced. Multivariate analysis of all lipids in the serum of five groups of mice showed there were obvious differences in lipid metabolism between the model group and the blank group. At the same time, seven kinds of differential lipids were precisely identified after screening, including prostaglandins, long-chain fatty acids, glycerophospholipids, acyl carnitines. In summary, alcohol intake and MFP intervention have significant effects on fatty acid synthesis, degradation and glycerophospholipid metabolism.

11.
J Healthc Eng ; 2021: 3774423, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34745497

RESUMO

This study focused on the application of deep learning algorithms in the segmentation of CT images, so as to diagnose chronic kidney diseases accurately and quantitatively. First, the residual dual-attention module (RDA module) was used for automatic segmentation of renal cysts in CT images. 79 patients with renal cysts were selected as research subjects, of whom 27 cases were defined as the test group and 52 cases were defined as the training group. The segmentation results of the test group were evaluated factoring into the Dice similarity coefficient (DSC), precision, and recall. The experimental results showed that the loss function value of the RDA-UNET model rapidly decayed and converged, and the segmentation results of the model in the study were roughly the same as those of manual labeling, indicating that the model had high accuracy in image segmentation, and the contour of the kidney can be segmented accurately. Next, the RDA-UNET model achieved 96.25% DSC, 96.34% precision, and 96.88% recall for the left kidney and 94.22% DSC, 95.34% precision, and 94.61% recall for the right kidney, which were better than other algorithms. The results showed that the algorithm model in this study was superior to other algorithms in each evaluation index. It explained the advantages of this model compared with other algorithm models. In conclusion, the RDA-UNET model can effectively improve the accuracy of CT image segmentation, and it is worth of promotion in the quantitative assessment of chronic kidney diseases through CT imaging.


Assuntos
Aprendizado Profundo , Insuficiência Renal Crônica , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador , Insuficiência Renal Crônica/diagnóstico por imagem , Tomografia Computadorizada por Raios X
12.
Artigo em Inglês | MEDLINE | ID: mdl-34618220

RESUMO

BACKGROUND: Adding neoadjuvant chemotherapy (NAC) to concurrent chemoradiotherapy (CCRT) is the main strategy in treatment of children and adolescents with locoregionally advanced nasopharyngeal carcinoma (CA-LANPC). Yet, an optimal number of NAC cycles remains unknown. We aimed to optimize the NAC cycle and potentially contribute to clinical decision making for the individual treatment of CA-LANPC. PATIENTS AND METHODS: Utilizing an NPC-specific database through an acknowledged big-data information system at our center, we identified 143 CA-LANPC treated with NAC followed by CCRT between September 2007 through April 2018. Recursive partitioning analysis (RPA) was performed to categorize the patients and predict disease-free survival (DFS). The clinical benefits of NAC cycles (two cycles vs three cycles) were assessed in each risk group. RESULTS: Independent factors derived from multivariable analysis to predict DFS were T stage (T1-3 vs T4) and plasma Epstein-Barr virus (EBV) DNA (< 4000 vs ≥ 4000 copies/mL) for risk stratification. Consequently, 87 (61%) participants were classified as low-risk group (T1-3 with low or high EBV DNA, and T4 with low EBV DNA) and the other 56 patients (39%) were classified as a high-risk group (T4 with high EBV DNA) through RPA, and corresponding 5-year DFS rates of 91.9% and 71.2%, respectively (p = 0.001). Among the high-risk group, patients receiving three cycles of NAC had statistically significant improvement in 5-year DFS over those who received two cycles of NAC (86.7% vs 59.1%; p = 0.020), while the survival benefit of three cycles NAC for low-risk groups were not observed (94.7% vs 89.7%; p = 0.652). CONCLUSIONS: We found three cycles of NAC with CCRT was a positive prognostic indicator for improved DFS for the high-risk group among CA-LANPC. However, whether low-risk patients could benefit from three cycles NAC needs further study.

13.
One Health ; 13: 100332, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34604493

RESUMO

The emerging coronavirus diseases such as COVID-19, MERS, and SARS indicated that animal coronaviruses (CoVs) spillover to humans are a huge threat to public health. Therefore, we needed to understand the CoVs carried by various animals. Wild hedgehogs were collected from rural areas in Wuhan and Xianning cities in Hubei Province for analysis of CoVs. PCR results showed that 5 out of 51 (9.8%) hedgehogs (Erinaceus amurensis) were positive to CoVs in Hubei Province with 3 samples from Wuhan City and 2 samples from Xianning City. Phylogenetic analysis based on the partial sequence of RNA-dependent RNA polymerase showed that the CoVs from hedgehogs are classified into Merbecovirus of the genus Betacoronavirus; the hedgehog CoVs formed a phylogenetic sister cluster with human MERS-CoVs and bat MERS-related CoVs. Among the 12 most critical residues of receptor binding domain in MERS-CoV for binding human Dipeptidyl peptidase 4, 3 residuals were conserved between the hedgehog MERS-related CoV obtained in this study and the human MERS-CoV. We concluded that hedgehogs from Hubei Province carried MERS-related CoVs, indicating that hedgehogs might be important in the evolution and transmission of MERS-CoVs, and continuous surveillance of CoVs in hedgehogs was important.

14.
Microbiol Res ; 253: 126883, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34626929

RESUMO

Vibrio alginolyticus belongs to gram-negative opportunistic pathogen realm infecting humans and aquatic animals causing severe economic losses. The (p)ppGpp-mediated stringent response is corroborated to stress adaptation and virulence of pathogenic mechanisms. Limited reports are documented for the intricate assessment of (p)ppGpp synthetase genes in combating various stress adaptation and elucidation of virulence in V. alginolyticus remains unraveled. The present assessment comprises of generation of deletion mutants in the (p)ppGpp-deficient strains, ΔrelA (relA gene single mutant) and ΔrelAΔspoT (relA and spoT genes double mutant), and the complemented strains, ΔrelA+ and ΔrelAΔspoT+, were constructed to investigate the pivotal roles of (p)ppGpp synthetase genes in V. alginolyticus, respectively. Amino acid sequence alignment analysis initially revealed that RelA and SpoT possess relatively conserved domains and synthetase activity. Hydrolase activity was emancipated by SpoT alone showing variant mode of action. Compared with the wild type and complemented strains, the relA-deficient strain was more sensitive to amino acid starvation and mupirocin. Interestingly, the deletion of spoT resulted in a significant growth deficiency supplemented with bile salts, 3 % ethanol and heat shock. Rapid growth was observed in the stationary phase upon exposure to cold stress and lower doses of ethanol. Subsequently, disruption of (p)ppGpp synthetase genes caused the decline in swimming motility, enhanced biofilm formation, cell aggregation of V. alginolyticus, and reduced mortality of Litopenaeus vannamei. The expression levels of some virulence-associated genes were quantified affirming consistency established by pleiotropic phenotypes. The results are evident for putative roles of (p)ppGpp synthetase genes attributing essential roles for environmental adaption and virulence regulation in V. alginolyticus.

15.
Nat Commun ; 12(1): 5953, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34642325

RESUMO

Triggered by the pioneering research on graphene, the family of two-dimensional layered materials (2DLMs) has been investigated for more than a decade, and appealing functionalities have been demonstrated. However, there are still challenges inhibiting high-quality growth and circuit-level integration, and results from previous studies are still far from complying with industrial standards. Here, we overcome these challenges by utilizing machine-learning (ML) algorithms to evaluate key process parameters that impact the electrical characteristics of MoS2 top-gated field-effect transistors (FETs). The wafer-scale fabrication processes are then guided by ML combined with grid searching to co-optimize device performance, including mobility, threshold voltage and subthreshold swing. A 62-level SPICE modeling was implemented for MoS2 FETs and further used to construct functional digital, analog, and photodetection circuits. Finally, we present wafer-scale test FET arrays and a 4-bit full adder employing industry-standard design flows and processes. Taken together, these results experimentally validate the application potential of ML-assisted fabrication optimization for beyond-silicon electronic materials.

16.
Metab Brain Dis ; 36(8): 2329-2341, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34665375

RESUMO

Type 2 diabetes mellitus (T2DM) is one of the most common chronic diseases among the elderly people. The T2DM increases the risk of cardio-cerebrovascular disease (CCD), and the main pathological change of the CCD is atherosclerosis (AS). Meanwhile, the carbonic anhydrases (CAs) are involved in the formation and progression of plaques in AS. However, the exact physiological mechanism of carbonic anhydrase III (CAIII) has not been clear yet, and there are also no correlation study between CAIII protein and T2DM with CCD. The 8-week old diabetic mice (db/db-/- mice) and wild-type mice (wt mice) were feed by a normal diet till 32 weeks, and detected the carotid artery vascular opening angle using the method of biomechanics; The changes of cerebral cortex and myocardium were watched by the ultrastructure, and the autophagy were observed by electron microscope; The tissue structure, inflammation and cell injury were observed by Hematoxylin and eosin (HE) staining; The apoptosis of cells were observed by TUNEL staining; The protein levels of CAIII, IL-17, p53 were detected by immunohistochemical and Western Blot, and the Beclin-1, LC3, NF-κB were detected by Western Blot. All statistical analysis is performed using PRISM software. Compared with wt mice, db/db-/- mice' carotid artery open angle increased significantly. Electron microscope results indicated that autophagy in db/db-/- mice cerebral cortex and heart tissue decreased and intracellular organelle ultrastructure were damaged. HE staining indicated that, db/db-/- mice' cerebral cortex and heart tissue stained lighter, inflammatory cells infiltration, cell edema were obvious, myocardial fibers were disorder, and myocardial cells showed different degrees of degeneration. Compared with wt mice, TUNEL staining showed that there was obviously increase in db/db-/- mice cortex and heart tissue cell apoptosis. The results of immunohistochemistry and Western Blot indicated that CAIII, Beclin-1 and LC3II/I expression levels conspicuously decreased in cortex and heart tissue of db/db-/- mice, and the expression level of IL-17, NF-κB and p53 obviously increased. The carotid artery' vascular stiffness was increased and which was probably related with formation of AS in diabetic mice. And the autophagy participated in the occurrence and development of diabetic CCD. CAIII protein might somehow be involved in the regulation of autophagy probably through affecting cell apoptosis and inflammation, but the underlying mechanism remains to be further studied.

17.
J Oleo Sci ; 70(11): 1641-1650, 2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34645748

RESUMO

Laggera pterodonta, known in China as 'Choulingdan' for its stimulous odor, has long been used as traditional herbal medicine. The essential oil of L. pterodonta, which exhibits various pharmacological activities, is a rich resource of monoterpenes and sesquiterpenes. To date, however, the terpene synthases responsible for their production remain unknown. In present study, a new terpene synthase gene (LpNES1) was identified from L. pterodonta, transcript level of which was significantly upregulated in response to methyl jasmonate treatment. Recombinant LpNES1 could synthesize (E)-nerolidol and minor ß-farnesene from farnesyl diphosphate and linalool from geranyl diphosphate in vitro. Whereas, only sesquiterpenes including (E)-nerolidol and minor ß-farnesene were released when LpNES1 was reconstituted in yeast, even coexpressed with a geranyl diphosphate synthase (ERG20WW). Combined with subcellular localization experiment, the result indicated that the cytosol-targeted LpNES1 was responsible for (E)-nerolidol biosynthesis exclusively in L. pterodonta. Additionally, the expression level of LpNES1 gene was more prominent in floral buds than that in other tissues. LpNES1 characterized in present study not only lays the molecular foundation for sesquiterpene biosynthesis of L. pterodonta, but provides a key element for further biosynthesis of bioactive compound in microbes.

18.
IEEE Trans Med Imaging ; PP2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34694992

RESUMO

Tucker decomposition can provide an intuitive summary to understand brain function by decomposing multi-subject fMRI data into a core tensor and multiple factor matrices, and was mostly used to extract functional connectivity patterns across time/subjects using orthogonality constraints. However, these algorithms are unsuitable for extracting common spatial and temporal patterns across subjects due to distinct characteristics such as high-level noise. Motivated by a successful application of Tucker decomposition to image denoising and the intrinsic sparsity of spatial activations in fMRI, we propose a low-rank Tucker-2 model with spatial sparsity constraint to analyze multi-subject fMRI data. More precisely, we propose to impose a sparsity constraint on spatial maps by using an ℓp norm (0

19.
Eur J Cell Biol ; 100(7-8): 151178, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34555639

RESUMO

Mast cells (MCs) play important roles in multiple pathologies, including fibrosis; however, their behaviors in different extracellular matrix (ECM) environments have not been fully elucidated. Accordingly, in this study, the migration of MCs on substrates with different stiffnesses was investigated using time-lapse video microscopy. Our results showed that MCs could appear in round, spindle, and star-like shapes; spindle-shaped cells accounted for 80-90 % of the total observed cells. The migration speed of round cells was significantly lower than that of cells with other shapes. Interestingly, spindle-shaped MCs migrated in a jiggling and wiggling motion between protrusions. The persistence index of MC migration was slightly higher on stiffer substrates. Moreover, we found that there was an intermediate optimal stiffness at which the migration efficiency was the highest. These findings may help to improve our understanding of MC-induced pathologies and the roles of MC migration in the immune system.

20.
Biochem Biophys Res Commun ; 576: 1-6, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34474244

RESUMO

Wnt signaling is one of the major signaling pathways that regulate cell differentiation, tissue patterning and stem cell homeostasis and its dysfunction causes many human diseases, such as cancer. It is of tremendous interests to understand how Wnt signaling is regulated in a precise manner both temporally and spatially. Naked cuticle (Nkd) acts as a negative-feedback inhibitor for Wingless (Wg, a fly Wnt) signaling in Drosophila embryonic development. However, the role of Nkd remains controversial in later fly development, particularly on the canonical Wg pathway. In the present study, we show that nkd is essential for wing pattern formation, such that both gain and loss of nkd result in the disruption of Wg target expression in larvae stage and abnormal adult wing morphologies. Furthermore, we demonstrate that a thirty amino acid fragment in Nkd, identified previously in Wharton lab, is critical for the canonical Wg signaling, but is dispensable for Wg/planar cell polarity pathway. Putting aside the pleiotropic nature of nkd function, i.e. its role in the Decapentaplegic signaling, we conclude that Nkd universally inhibits the canonical Wg pathway across a life span of Drosophila development.

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