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[Display omitted] Electrochemiluminescence (ECL) biosensors provide a convenient and high sensitivity method for early disease diagnosis. However, creating luminophore arrays relying on powerful ECL signals remains a daunting task. Porphyrin-centered metal organic frameworks (MOFs) exhibit remarkable potential in ECL sensing applications. In this paper, based on a simple one-pot synthesis method, PCN-222@Ag NPs doped with CeO 2 was synthesized to enhance the ECL performance. Due to the strong catalytic ability of CeO 2 , the ECL signal strength of the new material PCN-222@CeO 2 @Ag NPs is much higher than that of the PCN-222@Ag NPs and PCN-222. The luminous properties of PCN-222@CeO 2 @Ag NPs become more intense and stable due to the excellent electronic conductivity of Ag NPs. Based on the fact that CuS@PDA composite can quench the ECL signal of PCN-222@CeO 2 @Ag NPs, we constructed a novel sandwich ECL immune sensor for the detection of phosphorylated Tau 181 (p-Tau-181) protein. The ECL sensor has a great linear relationship with p-Tau-181 protein concentration, ranging from 1 pg/mL to 100 ng/mL. The detection limit is as low as 0.147 pg/mL. This work provides new ideas for developing sensitive ECL sensors for the p-Tau-181 protein, the marker of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Deep learning methods utilizing Convolutional Neural Networks (CNNs) and Transformers have achieved remarkable success in volumetric medical image analysis. While successful, the symmetrical structure of numerous networks pays insufficient attention to the encoding phase, and the large amount of memory occupied by voxels leads to unnecessary redundancy in the network. In this paper, we present a novel approach to handle volumetric medical images by converting them into point cloud and introduce a new asymmetrical segmentation architecture. We propose a dual-path encoder that fully captures both dense and sparse representations of the input point cloud sampled from volumes. Moreover, the two obtained representations are subtracted at the skip connection as a complementary feature during the decoding stage. Experimental results on the Brain Tumor Segmentation (BraTS) and the Multi-sequence Cardiac MR Segmentation tasks demonstrate the great potential of our point-based method for volumetric medical image segmentation. [ABSTRACT FROM AUTHOR]

There is a large subpopulation of multinucleated polyploid cardiomyocytes (M*Pc CMs) in the adult mammalian heart. However, the pathophysiological significance of increased M*Pc CMs in heart disease is poorly understood. We sought to determine the pathophysiological significance of increased M*Pc CMs during hypoxia adaptation. A model of hypoxia-induced cardiomyocyte (CM) multinucleation and polyploidization was established and found to be associated with less apoptosis and less reactive oxygen species (ROS) production. Compared to mononucleated diploid CMs (1*2c CMs), tetraploid CMs (4c CMs) exhibited better mitochondria quality control via increased mitochondrial autophagy (mitophagy). RNA-seq revealed Prkaa2 , the gene for AMPKα2, was the most obviously up-regulated autophagy-related gene. Knockdown of AMPKα2 increased apoptosis and ROS production and suppressed mitophagy in 4c CMs compared to 1*2c CMs. Rapamycin, an autophagy activator, alleviated the adverse effect of AMPKα2 knockdown. Furthermore, silencing PINK1 also increased apoptosis and ROS in 4c CMs and weakened the adaptive superiority of 4c CMs. Finally, AMPKα2−/− mutant mice exhibited exacerbation of apoptosis and ROS production via decreases in AMPKα2-mediated mitophagy in 4c CMs compared to 1*2c CMs during hypoxia. Compared to 1*2c CMs, hypoxia-induced 4c CMs exhibited enhanced mitochondria quality control and less apoptosis via AMPKα2-mediated mitophagy. These results suggest that multinucleation and polyploidization allow CM to better adapt to stress via enhanced mitophagy. In addition, activation of AMPKα2 may be a promising target for myocardial hypoxia-related diseases. Unlabelled Image • Hypoxia-induced tetraploid CMs were associated with enhanced mitophagy. • AMPKα2 is a key regulator of mitophagy in hypoxic tetraploid CMs. • AMPKα2 mediated mitophagy in tetraploid CMs by activating PINK1/Parkin signaling. [ABSTRACT FROM AUTHOR]

Salmonella enterica has been concerned globally due to its serious contamination in the food industry and serious risks to human health. In this study, the diversity of growth, genotypic virulence and clustered regularly interspaced short palindromic repeats (CRISPR) locus of 17 Salmonella enterica isolates from meat-related sources was evaluated. The results showed that the tested isolates exhibited significant differences (p < 0.05) in the growth kinetic behaviors, the growth rate was independent on serotype, and the fast-growing pattern was observed in Sinstorf serotype. The fold-change of nine genes involved in six virulence units showed isolate-to-isolate variation (p < 0.05), virulence genes associated with SPI-2 and SPI-4 displayed high expression. Relative lower expression levels of tested genes were obviously found in serotypes of Sinstorf, Stanley and Aberdeen. A considerable high diversity in repeats length and space numbers of both CRISPR-1 and CRISPR-2 among tested isolates was also observed, even within serotypes, which was also confirmed by the phylogenetic relationships. No significant relationship between the expression levels of each tested gene and the numbers of CRISPR spaces was observed. The information indicated that the variability among isolates of Salmonella with respect to their behavioral aspects is extensive, and assessment of strain variability is quite indispensable. [ABSTRACT FROM AUTHOR]

In this work we present a rapid and fully automated method to purify and desalt PCR products prior to analysis by electrospray ionization mass spectrometry. The protocol employs a commercial pipette tip packed with an anion-exchange resin and comprises four primary steps: tip pretreatment, sample loading, rinsing, and sample elution. This tip-based purification/desalting protocol has two distinct advantages over previously published methods. First, the protocol can be performed either manually (1–12 samples at a time), using a standard p10 manual pipette, or in a fully automated microtiter plate format (96 samples at a time) employing standard laboratory robotics. Additionally, the entire protocol from crude PCR product to an “electrosprayable” analyte solution requires only 10 μl of crude product and takes less than 20 min. Using capillary gel electrophoresis, we demonstrate an overall recovery efficiency of ∼80% and demonstrate the exquisite desalting efficiency with high-performance electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. Using an internal mass standard we demonstrate sub-ppm mass measurement error which provides an unambiguous base composition for a 120-mer PCR product. [Copyright &y& Elsevier]

[Display omitted] • Seven new meroterpenoids and two new polyketides were isolated from the fungus Paraphaeosphaeria sp. C-XB-J-1. • Compounds 1 and 7 exhibited significant anti-inflammatory activity. • Compounds 4 and 7 showed potential inhibitory effects on the SARS-CoV-2 Mpro. Seven new meroterpenoids, paraphaeones A-G (1 – 7), and two new polyketides, paraphaeones H-I (8 – 9), along with eight known compounds (10 – 17), were isolated from the endophytic fungus Paraphaeosphaeria sp. C-XB-J-1. The structures of 1 – 9 were identified through the analysis of 1H, 13C, and 2D NMR spectra, assisted by HR-ESI-MS data. Compounds 1 and 7 exhibited a dose-dependent decrease in lactate dehydrogenase levels, with IC 50 values of 1.78 μM and 1.54 μM, respectively. Moreover, they inhibited the secretion of IL-1 β and CASP-1, resulting in a reduction in the activity levels of NLRP3 inflammasomes. Fluorescence microscopy results indicated that compound 7 concentration-dependently attenuated cell pyroptosis. Additionally, compounds 4 and 7 showed potential inhibitory effects on the severe acute respiratory syndrome coronavirus-2 main protease (SARS-CoV-2 Mpro), with IC 50 values of 10.8 ± 0.9 μM and 12.9 ± 0.7 μM, respectively. [ABSTRACT FROM AUTHOR]

• A strain JI6 from ginseng rhizosphere soil as Pseudomonas thivervalensis. • To promote the growth of ginseng significantly and control rusty root rot. • To colonize and improve microbial community in rhizosphere soil of ginseng. The bacterial strain JI6, which has plant growth-promoting characteristics, was isolated from ginseng rhizosphere soil. It can produce indoleacetic acid (IAA), dissolve phosphorus, dissolve potassium and fix nitrogen and significantly promoted the growth of ginseng. The strain was identified as Pseudomonas thivervalensis by morphological, physiological and biochemical characteristics and 16S rDNA sequence analysis. The bud length of ginseng seeds treated with 109 CFU/mL JI6 suspension increased significantly by 42.76 % after 15 days. The fresh weight and the ginsenoside content of 3-year-old ginseng roots significantly increased by 38.72 % and 24.20 %, respectively with the 108 CFU/mL JI6 suspension for five months in the field. The strain JI6 can inhibit the six fungal pathogens and control rusty root rot of ginseng. For the biocontrol mechanism, the strain JI6 can colonize in ginseng rhizosphere soil. After treatment with JI6, the activitie of five ginseng defence enzymes of β-1.3 glucanase, peroxidase and phenylalanine ammonia-lyase, chitinase and superoxide dismutase and four soil enzymes of urease, phosphatase, invertase, and catalase significantly increased. The effect of strain JI6 on soil microbial community showed that the microbial diversity increased and the abundance of beneficial microorganisms elevated, while the abundance of pathogenic microorganisms decreased. This study indicate the great potential of P. thivervalensis JI6 for use as a biological agent for the control of ginseng rusty root rot. [ABSTRACT FROM AUTHOR]

Objective The aim of this study was to identify candidate pathogenic autoantigens of Behçet’s disease (BD) in pathogen-stimulated target cells. Methods First, three cell lines were used as target cells to screen autoantibody. Second, selected target cells were simulated with pathogens. Third, western blotting was used for detecting the auto-antigens in cell extracts. Next, immunoprecipitation was performed and the amino-acid sequences of target antigens were analyzed by LC-MALDI-TOF/TOF. Then, the potential target antigen was expressed, purified, and immunologically confirmed. And finally, an ELISA kit was developed and clinically validated through the assessments of 456 clinical samples with BD. Results One antigen with a molecular weight of approximately 27-kDa was identified as heat shock protein 27 (HSP27). The reactivity of serum IgG against recombinant human HSP27 was detected in 52 of 91 BD patients (57%), 66 of 92 rheumatoid arthritis (RA) patients (72%), 32 of 90 Sjogren syndrome (SS) patients (36%), 22 of 92 systemic lupus erythematosus (SLE) patients (24%) and 0 of 91 healthy controls (HC). The reactivity of BD serum IgG antibodies against HSP27 was significantly higher than SLE ( P < 0.0001) SS ( P < 0.0001) and HC ( P < 0.0001). Conclusions This study identified HSP27 as a candidate endothelial cell autoantigen of BD, which is interesting and probably worth further exploration. [ABSTRACT FROM AUTHOR]

Abstract: Pituitary adenylate cyclase activating polypeptide (PACAP) and growth hormone-releasing hormone (GHRH) are regulators of growth hormone secretion. In this article, we examined the difference in growth and mRNA expression of PACAP and GHRH between the sexes in half-smooth tongue sole, an important cultured fish species indicating sexually growth dimorphism in China. Firstly, a significant body weight difference between females and males was first observed at 7months (P <0.05) and at 18months the mean body weight of the females (771.0±44.3g) was as much as 4.9 times higher than that of males (130.6±6.0g). As a result, half-smooth tongue sole, Cynoglossus semilaevis, is a good model to investigate the effects of growth-related genes expression on sexual growth dimorphism. Secondly, the cDNAs encoding PRP/PACAP and GHRH were isolated. Two differently processed mRNA transcripts of PRP/PACAP (PRP-encoding and PRP splice variant) were found. PACAP and GHRH mRNA was highly abundant in brain and less abundant in other tissues. However, PACAP mRNA was expressed in most brain regions, and was lower in the cerebellum. GHRH mRNA was predominantly expressed in the hypothalamus and weakly expressed in all areas of the brain examined. Ontogenetic expression analysis indicated that PACAP and GHRH mRNA was detected in the early stages of embryogenesis. Finally, differential expression showed that there was no significant difference of the expression level of PACAP or GHRH between the sexes before 8months of age. However, between 9 and 12months of age, the GHRH mRNA expression level in males was significantly higher than in females (P <0.05), which might be associated with GH deficiency in males. In contrast, the male PACAP mRNA expression level was not significantly higher than that in females even at 9 and 12months of age. The present results provide important clues for understanding the sexual growth dimorphism mechanisms in half-smooth tongue sole. [ABSTRACT FROM AUTHOR]

Abstract: It was already known that both mind bomb (mib) and mind bomb-2 (mib2) encode E3 ubiquitin ligases that target Delta in Notch activation. Here we further demonstrated that zebrafish Mib and Mib2, similar to their mouse orthologs, have a C-terminal-most RING finger-dependent E3 ubiquitin ligase activity. Mib and Mib2 are reciprocal E3 ubiquitin ligases and substrates. They function similarly in Notch signaling by using DeltaC as a common substrate. However, Mib2 behaves differently from Mib in DeltaD internalization. In addition, Mib and Mib2 bind differently to extracellular and intracellular parts of DeltaA and DeltaC. Finally, mutant Mibs, Mibta52b with a missense mutation in the C-terminal-most RING finger (M1013R) and Mibm132 with a premature stop codon that leads to a deletion of three RING fingers (C785stop), act dominant-negatively and compete with Mib2 in DeltaC ubiquitylation and internalization, suggesting a molecular basis for the antimorphic phenotypes (stronger than the null phenotypes) observed in zebrafish mib ta52b and mib m132 alleles. [Copyright &y& Elsevier]

Abstract: In traditional approaches, mitochondrial DNA (mtDNA) variation is exploited for forensic identity testing by sequencing the two hypervariable regions of the human mtDNA control region. To reduce time and labor, single nucleotide polymorphism (SNP) assays are being sought to possibly replace sequencing. However, most SNP assays capture only a portion of the total variation within the desired regions, require a priori knowledge of the position of the SNP in the genome, and are generally not quantitative. Furthermore, with mtDNA, the clustering of SNPs complicates the design of SNP extension primers or hybridization probes. This article describes an automated electrospray ionization mass spectrometry method that can detect a number of clustered SNPs within an amplicon without a priori knowledge of specific SNP positions and can do so quantitatively. With this technique, the base composition of a PCR amplicon, less than 140 nucleotides in length, can be calculated. The difference in base composition between two samples indicates the presence of an SNP. Therefore, no post-PCR analytical construct needs to be developed to assess variation within a fragment. Of the 2754 different mtDNA sequences in the public forensic mtDNA database, nearly 90% could be resolved by the assay. The mass spectrometer is well suited to characterize and quantitate heteroplasmic samples or those containing mixtures. This makes possible the interpretation of mtDNA mixtures (as well as mixtures when assaying other SNPs). This assay can be expanded to assess genetic variation in the coding region of the mtDNA genome and can be automated to facilitate analysis of a large number of samples such as those encountered after a mass disaster. [Copyright &y& Elsevier]

Vertebrate segmentation is manifested during embryonic development as serially repeated units termed somites that give rise to vertebrae, ribs, skeletal muscle and dermis. Many theoretical models including the “clock and wavefront” model have been proposed. There is compelling genetic evidence showing that Notch–Delta signaling is indispensable for somitogenesis. Notch receptor and its target genes, Hairy/E(spl) homologues, are known to be crucial for the ticking of the segmentation clock. Through the work done in mouse, chick, Xenopus and zebrafish, an oscillator operated by cyclical transcriptional activation and delayed negative feedback regulation is emerging as the fundamental mechanism underlying the segmentation clock. Ubiquitin-dependent protein degradation and probably other posttranslational regulations are also required. Fgf8 and Wnt3a gradients are important in positioning somite boundaries and, probably, in coordinating tail growth and segmentation. The circadian clock is another biochemical oscillator, which, similar to the segmentation clock, is operated with a negative transcription-regulated feedback mechanism. While the circadian clock uses a more complicated network of pathways to achieve homeostasis, it appears that the segmentation clock exploits the Notch pathway to achieve both signal generation and synchronization. We also discuss mathematical modeling and future directions in the end. [Copyright &y& Elsevier]

Background. Growth hormone (GH) has been shown to increase mortality in critical illness, illustrating the need for better understanding of GH treatment. The neutrophil is a key mediator in producing organ injury following shock and trauma and is regulated by GH. Therefore, the purpose of the present study was to examine the effects of GH on circulating neutrophil activation and subsequent lung injury induced by sepsis in rats.Materials and methods. Sepsis was induced in male Wistar rats via cecal ligation and puncture (CLP). Recombinant human growth hormone (1 IU/kg) was given subcutaneously right after CLP with an additional injection at 12 h after CLP. CD11b expression and an oxidative burst of neutrophils were detected using flow cytometric analysis. Lung myeloperoxidase activity was determined as an index of tissue neutrophil accumulation. Lung microvascular injury was assessed by quantitating extravasation of Evan''s blue dye into lung parenchyma.Results. Growth hormone significantly increased sepsis-induced expression of CD11b and sepsis-induced circulating neutrophil activation. Also growth hormone increased neutrophil accumulation in lungs induced by sepsis. Lung microvascular injury was aggravated by growth hormone treatment in septic rats.Conclusions. It is worthwhile to rethink GH administration in critical illness and further studies are required to determine the safety and clinical benefits of GH administration in critical illness. [Copyright &y& Elsevier]

• Bacillus amyloliquefaciens FG14 has an excellent antagonistic effect on Ilyonectria robusta. • The strain FG14 has the ability to control disease and promote root growth of ginseng. • The rhizosphere microbial community and soil enzyme activities of ginseng were improved. • The expression of lipopeptide biosynthesis genes was up-regulated. Rusty root rot is the most destructive disease in ginseng production. The bacterial strain FG14 isolated from the rhizosphere of Panax ginseng was characterised as Bacillus amyloliquefaciens. The inhibition rates of the FG14 bacterial suspension against the mycelial growth, spore production and spore germination of Ilyonectria robusta which causes ginseng rusty root rot were all more than 90% at a concentration of 108 cfu/mL. The sterile fermentation broth of strain FG14 also had significant inhibitory ability. The results of plantgrowth promotion showed that the fresh weight and root length of ginseng seedlings treated with 3 × 108 cfu/mL FG14 bacterial suspension were 4.49 times and 2.12 times greater than the seedlings treated with I. robusta. The soil enzyme activities of urease, phosphatase, invertase, and catalase of strain FG14 and the expression of seven lipopeptide biosynthesis genes were up-regulated, and antifungal metabolite production was stable. The diversity and abundance of bacterial and fungal communities in rhizosphere soil changed during different growth stages of ginseng after inoculation with strain FG14. The relative abundance of the Ilyonectria genus was significantly lower than the water control at the leaf spreading stage of P. ginseng. These results indicate the great potential of B. amyloliquefaciens FG14 for use as a biological agent for the green control of ginseng rusty root rot. [ABSTRACT FROM AUTHOR]

Pseudomonas fragi and Escherichia coli are considered as common colonizers of fresh and spoilage meat, where they tend to live in the proximity. In this study, we primarily tested interplay patterns between different isolates of these two species in two-by-two combinations grown on stainless steel surfaces as dual-species biofilms. Results showed that these two species presented competition as major observed interplay patterns as biofilms progressed independent of bacterial strains and growth temperatures (15 °C and 25 °C). One dual-species combination was proposed as a representative to further explore dynamic patterns of interaction strength between these two species, with species colonization order taken into consideration as a biological effector. We firstly reported that prior colonization of one species significantly decreased the initiatively colonized cell counts of counterpart species by one to three orders of magnitude when competing for limited adhesion surface, under which E. coli was observed to be more aggressive in surface colonization as compared to P. fragi. However, the spatial structure and microbial composition of mature dual-species biofilms were not observed to be significantly affected. Our findings also shed new light on the evidence that E. coli and P. fragi , respectively, enhanced their biofilm formation capabilities by upregulating expression level of genes that encoded Type 1 fimbriae and phosphate response regulator as dual-species consortia progressed, which could serve as a crucial factor that improved the difficulty of food biocontrol. • Interplay patterns between different isolates of E. coli and P. fragi grown as biofilms. • Prior colonization enhanced competitive strength for occupying limited surface. • E. coli was more aggressive in surface occupation as adhesion surface was limited. • Two species co-survived by adjusting gene-regulated competitive strength. • Upregulation of fimH and phoR indicating increased biofilm formation capability. [ABSTRACT FROM AUTHOR]

Escherichia coli O157:H7 and Pseudomonas were considered as common colonizers of fresh and spoilage meat, where they tended to live in the proximity. In this study, we tested the interplay between different isolates of E. coli O157:H7 and Pseudomonas in random two-by-two combinations grown as dual-species consortia. Results showed that the growth fitness of E. coli was not facilitated by the presence of all tested Pseudomonas strains, and vice versa. Representative combinations were further selected to investigate the property changes following the time course of biofilms formation as compared to single species. Cell counting confirmed that the growth of E. coli O157:H7 was challenged by the presence of Pseudomonas strains as previously described. Our findings shed new light on the evidence that the pathogenicity of E. coli O157:H7 was negatively affected by the presence of Pseudomonas according to the evaluation of spatial organization and genetic expression of virulence factors, which might be a naturally existing biological phenomenon constraining the safety risk of former strains in meat processing and preservation. Intriguingly, we observed that E. coli managed to stably co-exist at low cellular abundance in the progress of dual-species consortia, indicating successful adaptive mechanisms that need further investigations to uncover. • The interplay between different isolates of E. coli O157:H7 and Pseudomonas. • E. coli O157:H7 managed to stably co-exist at low biomass in dual-species biofilm. • Virulence genes expression in E. coli O157:H7 was reduced by Pseudomonas. [ABSTRACT FROM AUTHOR]

• Showing an antagonistic effect of B. methylotrophicus on I. robusta. • Sequencing the genome of biocontrol B. methylotrophicus. • Exploring the DEGs of B. methylotrophicus in interaction of bacterial-fungal. • Revealing the molecular response pattern of B. methylotrophicus to I. robusta. To explain the molecular mechanism of the biocontrol exerted by Bacillus methylotrophicus NJ13 against Ilyonectria robusta , this study mainly focused on the following aspects. (i) Background: I. robusta is a dominant species of soil-borne pathogen causing ginseng rusty root rot. The ginseng endophytic bacteria B. methylotrophicus NJ13 can effectively inhibit the growth of I. robusta DQX01 and control the disease. (ii) Methods: Through in vitro antagonism experiments and microscopic observation, the inhibitory effect of the strain NJ13 against strain DQX01 was determined. The whole genome of NJ13 was sequenced by using the Illumina NovaSeq PE150 platform, and the gene expression pattern of NJ13 against DQX01 was revealed by using RNA-seq. (iii) Results: NJ13 could significantly inhibit the growth of DQX01, leading to the mycelial and conidia of DQX01 appearing abnormal and swollen. The genome of NJ13 consists of a circular chromosome of 3,929,584 bp, with 4024 coding DNA sequences (CDSs). The number of NJ13 differentially expressed genes (DEGs) (| log2 (fold change) | > 1, q < 0.005) was 691, of which 233 were upregulated and 458 downregulated. (iv) Conclusions: According to both in vivo and in vitro experiments, NJ13 shows good antagonistic activity against DQX01. Secondary metabolite gene clusters probably regulate the good antagonistic effect, as demonstrated through the analysis of strain NJ13′s genome. When the strain NJ13 interacted with DQX01, a defensive response within B. methylotrophicus NJ13 was triggered. The transcriptomic profiling of NJ13 could provide an explanation for this phenomenon. [ABSTRACT FROM AUTHOR]

The enzyme 8-oxoguanine glycosylase 1 (OGG1) has been shown to be involved in the repair of oxidative DNA damage. However, the effect of OGG1 on oxidative DNA damage caused by particulate matter 2.5 (PM2.5) is unknown. Herein, we demonstrated that OGG1 could inhibit the generation of ROS and alleviate mitochondrial dysfunction and increased the expression of IL-1β caused by PM2.5. The dichlorodihydrofluorescein diacetate (DCFH-DA) staining and 5,5′,6,6′-tetrachloro-1,1′,3,3′-. tetraethylbenzi - midazolylcarbocyanine iodide (JC-1) staining using flow cytometry showed that PM2.5 induces the generation of ROS and leads to a reduction in mitochondrial membrane potential (MMP) in BEAS-2B cells. Overexpression of OGG1 inhibited the generation of ROS and the decline in MMP. Knockdown of OGG1 by RNA interference (RNAi) increased the generation of ROS and reduced the MMP. Real-time quantitative PCR (RT-qPCR) for the mitochondrial DNA copy number (mtDNAcn) and flow cytometry for apoptosis revealed that OGG1 inhibits the apoptosis and decreases mtDNAcn induced by PM2.5. Additionally, the results of the comet assay showed that OGG1 had a significant repair effect on DNA strand breaks caused by PM2.5. Overexpression of OGG1 also significantly suppressed the expression of IL-1β caused by PM2.5. Together, these data suggest that PM2.5 leads to mitochondrial dysfunction and the up-regulation of IL-1β could be reversed by overexpression of OGG1. The mitochondrial dysfunction caused by PM2.5 could be relieved by OGG1. Thus, the base excision repair enzyme OGG1 may alleviate mitochondrial dysfunction caused by PM2.5 involved in the expression of IL-1β. [ABSTRACT FROM AUTHOR]

The use of selenium (Se)-rich soils in China is an effective method for rural revitalization, but assessment of heavy metals is essential prior to the development of Se-rich soils. This study was focused on the Jiangjin district, a typical Se-rich area located in Sichuan Basin of China, to investigate contamination, influencing factors, and sources of As, Cr, Cu, Cd, Ni, Pb, Sb, and Zn based on 156 topsoil samples. This study analyzed and compared the enrichment factor (EF), Nemerow index (P N), geographical information system (GIS), and positive matrix factorization (PMF). Results demonstrate that the average values of As, Cu, Cd, Sb, and Zn in topsoil were higher than the soil background values of western Chongqing by approximately 1.75, 1.11, 1.27, 1.71, and 2.58 times, respectively, indicating that some heavy metals have been enriched in the soils. The polluted areas of As, Cu, Cd, and Zn in topsoil were mainly distributed in the northern and central Jiangjin district, whereas high-Sb soils were located in the southeast. The Cr, Cu, Cd, Pb, and Sb were concentrated in Se-rich soils, indicating that heavy metals pollution should be carefully considered for the utilization of Se-rich soils. Four potential sources of heavy metals were found in this study area: 1) the parent materials (Cr, Ni, Cu); 2) industrial activities with high coal consumption (As); 3) mechanical and chemical industrial activities (Zn, Sb); and 4) transportation and agricultural activities (Pb, Cd). These observations provide a scientific basis for the development, utilization, and protection of Se-rich soil resources. • A comprehensive heavy metals pollution and assessment of Se-rich soil was conducted. • Nemerow pollution index mainly showed slight polluted soil. • Cr (58.5%), Ni (56.1%), and Cu (53.9%) mainly came from natural sources. • As (85.9%) was derived mainly from high coal consumption industrial activities. • Cd (73.8%) was mainly attributed to agricultural activities. [ABSTRACT FROM AUTHOR]

Abstract: The broad diversity of neurons is vital to neuronal functions. During vertebrate development, the spinal cord is a site of sensory and motor tasks coordinated by interneurons and the ongoing neurogenesis. In the spinal cord, V2-interneuron (V2-IN) progenitors (p2) develop into excitatory V2a-INs and inhibitory V2b-INs. The balance of these two types of interneurons requires precise control in the number and timing of their production. Here, using zebrafish embryos with altered Notch signaling, we show that different combinations of Notch ligands and receptors regulate two functions: the maintenance of p2 progenitor cells and the V2a/V2b cell fate decision in V2-IN development. Two ligands, DeltaA and DeltaD, and three receptors, Notch1a, Notch1b, and Notch3 redundantly contribute to p2 progenitor maintenance. On the other hand, DeltaA, DeltaC, and Notch1a mainly contribute to the V2a/V2b cell fate determination. A ubiquitin ligase Mib, which activates Notch ligands, acts in both functions through its activation of DeltaA, DeltaC, and DeltaD. Moreover, p2 progenitor maintenance and V2a/V2b fate determination are not distinct temporal processes, but occur within the same time frame during development. In conclusion, V2-IN cell progenitor proliferation and V2a/V2b cell fate determination involve signaling through different sets of Notch ligand–receptor combinations that occur concurrently during development in zebrafish. [Copyright &y& Elsevier]

Epigallocatechin gallate loaded melanin nanoparticles (EGCG@MNPs) have been prepared aiming for the development of an eco-friendly food preservation nanomaterials with good thermal stability, antioxidant and antibacterial activity. The EGCG@MNPs presents a uniform and well dispersed spherical structure with average diameter below 100 nm. The structure analysis results show that EGCG@MNPs exist in the form of macromolecular polymers rather than crystalline structure, and EGCG was loaded onto MNPs via hydrophobic interaction and Π-Π stacking. Moreover, EGCG@MNPs has superior thermal stability and antioxidant activity. After processing at 121 °C, the scavenging ratio of EGCG@MNPs on DPPH• and ABTS•+ were 67.14 ± 1.35% and 46.99 ± 1.12%, respectively, while the value of pure EGCG on DPPH• and ABTS•+ were only 38.37 ± 0.67% and 4.01 ± 0.93%. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of EGCG@MNPs to Escherichia coli and Staphylococcus aureus were 0.8 mg/mL, 1.6 mg/mL and 0.2 mg/mL, 0.4 mg/mL respectively. In summary, the MNPs provided stable media to bind EGCG and the resulted EGCG@MNPs nanoparticles retained strong antioxidant and antibacterial properties after heat treated, which suggested the potential of EGCG@MNPs for the development of new food preservation nanomaterials and/or food active packaging fillers. • The EGCG@MNPs nanoparticles was successfully prepared. • EGCG@MNPs nanoparticles were uniformly distributed below 100 nm. • The prepared nanoparticles significantly enhanced the thermal stability of EGCG. • The EGCG in nanoparticles retained good antioxidant activity after heat treatment. • EGCG loaded melanin nanoparticles exhibited remarkable antibacterial activity. [ABSTRACT FROM AUTHOR]

Abstract: Both mind bomb (mib) and mind bomb-2 (mib2) encode RING E3 ubiquitin ligases that promote Delta ubiquitylation and endocytosis in Notch activation. Detailed morphological and molecular examinations revealed that zebrafish mib ta52b (missense mutation in the C-terminal RING Finger (RF), M1013R) and mib m132 (nonsense mutation resulting in a truncated protein that loses all three RFs, C785stop) are strong and weak antimorphic alleles, respectively, compared to the null allele, mib tfi91 (nonsense mutation resulting in a truncated protein of only 60 amino acids, Y60stop). Zebrafish mib2 ortholog was identified in this study. Zebrafish Mib and Mib2 are colocalized in transfected cells and function redundantly in regulating Notch signaling in embryos. Mibta52b and Mibm132 have a dosage-dependent dominant-negative effect, at least, on Mib2, which is a molecular basis for the antimorphic phenotypes. It was also shown that Notch signaling negatively regulates mib expression in a Su(H)-dependent manner, forming a negative feedback loop in modulating Notch activation. [Copyright &y& Elsevier]

Abstract: In contrast to what we know on development of endocrine pancreas, the formation of exocrine pancreas remains poorly understood. To create an animal model that allows observation of exocrine cell differentiation, proliferation, and morphogenesis in living animals, we used the zebrafish elastaseA (elaA) regulatory sequence to develop transgenic zebrafish that display highly specific exocrine pancreas expression of GFP in both larvae and adult. By following GFP expression, we found that the pancreas in early development was a relatively compact organ and later extended posterior along the intestine. By transferring the elaA:gfp transgene into slow muscle omitted mutant that is deficient in receiving Hedgehog signals, we further showed that Hedgehog signaling is required for exocrine morphogenesis but not for cell differentiation. We also applied the morpholino knockdown and toxin-mediated cell ablation approaches to this transgenic line. We showed that the development of exocrine pancreas is Islet-1 dependent. Injection of the diphtheria toxin A (DTA) construct under the elastaseA promoter resulted in selective ablation of exocrine cells while the endocrine cells and other endodermal derivatives (liver and intestine) were not affected. Thus, our works demonstrated the new transgenic line provided a useful experimental tool in analyzing exocrine pancreas development. [Copyright &y& Elsevier]

Abstract: The Tübingen large-scale zebrafish genetic screen completed in 1996 identified a set of five genes required for orderly somite segmentation. Four of them have been molecularly identified and three were found to code for components of the Notch pathway, which are required for the coordinated oscillation of gene expression, known as the segmentation clock, in the presomitic mesoderm (PSM). Here, we show that the final member of the group, beamter (bea), codes for the Notch ligand DeltaC, and we present and characterize two new alleles, including one allele encoding for a protein truncated in the 7th EGF repeat and an allele deleting only the DSL domain which was previously shown to be necessary for ligand function. Interestingly however, when we over-express any of the mutant deltaC mRNAs, we observe antimorphic effects on both hindbrain neurogenesis and hypochord formation. Expression of bea/deltaC oscillates in the PSM, and a triple fluorescent in situ analysis of its oscillation in relation to that of other oscillating genes in the PSM reveals differences in subcellular localization of the oscillating mRNAs in individual cells in different oscillation phases. Mutations in aei/deltaD and bea/deltaC differ in the way they disrupt the oscillating expression of her1 and deltaC. Furthermore, we find that the double mutants have significantly stronger defects in hypochord formation but not in somitogenesis or hindbrain neurogenesis, indicating genetically that the two delta''s may function either semi-redundantly or distinctly, depending upon context. [Copyright &y& Elsevier]

Shiga toxin-producing Escherichia coli (STEC) strains are classified as important foodborne pathogens and their acid resistance (AR) capability is identified as one of key factors compromising food safety. In this study, we confirmed experimentally that the growth of two STEC strains (O157:H7 and O26:H11) was remarkably inhibited in Luria-Bertani medium (final pH 3.5) supplemented with lactic acid. Transcriptomic analysis indicated that several AR mechanisms employed by these two strains were also reported previously, and represented similar tendency in transcriptomic profiles variation in response to the acid treatment. However, strain O157 showed much more times up-regulation of genes involved in quorum sensing (QS) and biofilm formation as compared to strain O26, indicting the stronger acid resistance capability of the former strain. Most importantly, we first reported that enhanced cysteine biosynthesis might play an essential role in acid resistance of these two strains when treated for longer time, which was not presented in previous studies with short time acid treatment. Our results shed substantial light on following studies deciphering AR mechanisms of microbes with time course, and this will provide profound insights for better control of microbial induced food contamination. • E. coli O157:H7 and O26:H11 had a high level of acid resistance (AR) capability. • E. coli O157 and O26 presented similar gene expression profiles in acid stress. • In E. coli O157, quorum sensing was induced to help cell survival under acid stress. • The cysteine biosynthesis might play an essential role in acid resistance of E. coli O157 and O26. [ABSTRACT FROM AUTHOR]

O157 is the most common serogroup of Enterohemorrhagic Escherichia coli responsible for the most outbreaks, partly due to its acid tolerance. Biofilm formation of E. coli O157:H7 and its response to lactic acid stress were determined in this study. Results showed that the biofilm formation of 11 isolates greatly depended on the strain; specifically, the J29 isolate showed strong capacity. As compared to CICC 21530 isolate exhibiting weak capacity of biofilm formation on polystyrene microplates, a classic dynamic of biofilm formation was observed for J29. The growth of biofilm and planktonic cells of selected strains (J29 and CICC 21530) varied after exposure to pH 4.0, 4.5, 5.0, and 7.2 (control). A similar survival and growth profiles of planktonic cells response to stress was found between J29 and CICC 21530, whereas J29 showed high resistance to acid stress during biofilm formation, which was further confirmed using SEM. Moreover, the formed-biofilm of J29 showed more resistance to pH 2.0 and 3.5, with more than 4 log CFU/cm2 cells remaining after 12 h treatment, whereas less than 3 log CFU/cm2 cells survived for CICC 21530. The finding suggested that a combination of interventions might be an effective intervention for eliminating the biofilm. • The attachment ability of Escherichia coli O157:H7 were evaluated. • J29 isolate can form high biofilm after exposure to acid stress. • The formed-biofilm of J29 showed certain resistance to pH 2.0 [ABSTRACT FROM AUTHOR]

This study was aimed to investigate the dynamic recovery process of high pressure processing (HPP)-injured Escherichia coli O157:H7. E. coli O157:H7 was treated with 100–500 MPa for 5 min, and the pressure with highest injury rate was selected to determine the optimal temperature and duration for repairing HPP-injured cells in PBS. The morphological and physiological changes during the repair process under the above optimal conditions were further investigated. The results showed a stronger inhibition effect with increased pressure, while the lethal effect was not consistent with the injury, since the highest injury rate was observed at 400 MPa for 5 min. Next, HPP-treated cells (400 MPa, 5 min) were repaired in PBS at different temperatures (20, 25, 30, 37 °C) for 108 h, and the optimal recovery condition of the injured cells was found to be 25 °C for 24 h. During the repair process, SEM and TEM morphology, leakage of ions, activities of Na+K+-ATPase and Ca2+Mg2+-ATPase, and the membrane fatty acid composition of HPP-treated cells gradually return to normal levels found in non-HPP cells, which confirmed the dynamic recovery process of HPP-injured E. coli O157:H7, as well as that HPP-injured E. coli O157:H7 could be repaired under appropriate conditions. • Optimal temperature and duration for recovery of injured cell in PBS was studied. • Morphology of injured cells returned towards normal levels during repair process. • Physiology of injured cells returned towards normal levels during repair process. [ABSTRACT FROM AUTHOR]