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Potential toxic metal (PTM) is hazardous to human health, but the mechanism of spatial heterogeneity of PTM at a macro-scale remains unclear. This study conducts a meta-analysis on the data of PTM concentrations in the soil of 164 major cities in China from 2006 to 2021. It utilizes spatial analysis methods and geodetector to investigate the spatial distribution characteristics of PTMs. The geographic information systems (GIS) and geodetector were used to investigate the spatial distribution characteristics of PTMs, assess the influence of natural factors (NFs) and anthropogenic factors (AFs) on the spatial heterogeneity of PTMs in urban soils, and identified the potential pollution areas of PTMs. The results indicated that the pollution levels of PTMs in urban soils varied significantly across China, with higher pollution levels in the south than in the north. Cd and Hg were the most severely contaminated elements. The geodetector analysis showed that temperature and precipitation in NFs and land use type in AFs were considered as the main influencing factors, and that both AF and NF together led to the PTM variation. All these factors showed a mutually enhancing pattern which has important implications for urban soil management. PTM high-risk areas were identified to provide early warning of pollution risk under the condition of climate change.
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Cidades , Monitoramento Ambiental , Poluentes do Solo , China , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Sistemas de Informação Geográfica , Solo/química , Análise Espacial , Metais Pesados/análise , Metais/análiseRESUMO
Here, we report a draft genome sequence of endophytic fungus Nemania diffusa YAFEF818, isolated from Artemisia argyi. Oxford Nanopore Technologies PromethION and Illumina NovaSeq sequence reads were assembled using NECAT and polished using pilon to yield a 55.63 Mb genome.
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In the sphere of urban renewal of historic districts, preserving and innovatively reinterpreting traditional architectural styles remains a primary research focus. However, the modernization and adaptive reuse of traditional buildings often necessitate changes in their functionality. To cater to the demands of tourism in historic districts, many traditional residential buildings require conversion to commercial use, resulting in a mismatch between their external form and their internal function. This study explored an automated approach to transform traditional residences into commercially viable designs, offering an efficient and scalable solution for the modernization of historic architecture. We developed a methodology based on diffusion models, focusing on a dataset of nighttime shopfront facades. By training a low-rank adaptation (LoRA) model and integrating the ControlNet model, we enhanced the accuracy and stability of the generated images. The methodology's performance was validated through qualitative and quantitative assessments, optimizing the batch size, repetition, and learning rate configurations. These evaluations confirmed the method's effectiveness. Our findings significantly advance the modern commercial style transformation of historical architectural facades, providing a novel solution that maintains the aesthetic and functional integrity, thereby fostering breakthroughs in traditional design thinking and exploring new possibilities for the preservation and commercial adaptation of historical buildings.
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Ultra performance liquid chromatography-high resolution mass spectrometry (UPLC-MS/MS) were used to target quantitative determination anthocyanins and flavonoids in the fresh leaves (purple and green) of Eleutherococcus senticosus. The results showed that the content of total anthocyanins was 99.68 µg/g (Fresh Weight, FW) in purple leaves and 29.12 µg/g in green leaves. Cyanidin-3-O-galactoside and delphinidin were the main anthocyanins compound in purple and green leaves, and the content of the both declined sharply in green leaves. The content of cyanidin-3-O-galactoside reached 616.23 ng/100 mg in purple leaves and was only fifth in green leaves. The total flavonoids content was 4.90 mg/g in purple leaves and 2.23 mg/g in green leaves. Quercetin-3-ß-D-glucoside (236.96 ng/mg) and kaempferol-3-O-glucoside (145.27 ng/mg) were the main flavonoids compound in purple leaves. Besides the two main flavonoids, large quantities of rutin (269.11 ng/mg) was detected in green leaves of E. senticosus.
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Iron overload can lead to oxidative stress and intestinal damage and happens frequently during blood transfusions and iron supplementation. However, how iron overload influences intestinal mucosa remains unknown. Here, the aim of current study was to investigate the effects of iron overload on the proliferation and differentiation of intestinal stem cells (ISCs). An iron overload mouse model was established by intraperitoneal injection of 120 mg/kg body weight iron dextran once a fortnight for a duration of 12 weeks, and an iron overload enteroid model was produced by treatment with 3 mM or 10 mM of ferric ammonium citrate for 24 h. We found that iron overload caused damage to intestinal morphology with a 64 % reduction in villus height/crypt depth ratio, and microvilli injury in the duodenum. Iron overload mediated epithelial function by inhibiting the expression of nutrient transporters and enhancing the expression of secretory factors in the duodenum. Meanwhile, iron overload inhibited the proliferation of ISCs and regulated their differentiation into secretory mature cells, such as goblet cells, through inhibiting Notch signaling pathway both in mice and enteroid. Furthermore, iron overload caused oxidative stress and ferroptosis in intestinal epithelial cells. In addition, ferroptosis could also inhibit Notch signaling pathway, and affected the proliferation and differentiation of ISCs. These findings reveal the regulatory role of iron overload on the proliferation and differentiation of ISCs, providing a new insight into the internal mechanism of iron overload affecting intestinal health, and offering important theoretical basis for the scientific application of iron nutrition regulation.
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Diferenciação Celular , Ferroptose , Células Caliciformes , Sobrecarga de Ferro , Estresse Oxidativo , Receptores Notch , Transdução de Sinais , Células-Tronco , Animais , Ferroptose/efeitos dos fármacos , Camundongos , Células Caliciformes/metabolismo , Sobrecarga de Ferro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células-Tronco/metabolismo , Células-Tronco/citologia , Diferenciação Celular/efeitos dos fármacos , Receptores Notch/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , MasculinoRESUMO
Retinal inflammation is a pivotal characteristic observed in various retinal degenerative disorders, notably age-related macular degeneration (AMD), primarily orchestrated by the activation of microglia. Targeting the inhibition of microglial activation has emerged as a therapeutic focal point. Quercetin (Qu), ubiquitously present in dietary sources and tea, has garnered attention for its anti-neuroinflammatory properties. However, the impact of Qu on retinal inflammation and the associated mechanistic pathways remains incompletely elucidated. In this study, retinal inflammation was induced in adult male C57BL/6 J mice through intraperitoneal administration of LPS. The results revealed that Qu pre-treatment induces a phenotypic shift in microglia from M1 phenotype to M2 phenotype. Furthermore, Qu attenuated retinal inflammation and stabilized the integrity of the blood-retina barrier (BRB). In vitro experiments revealed that Qu impedes microglial activation, proliferation, and migration, primarily via modulation the ERK/STAT3 signaling pathway. Notably, these actions of Qu significantly contributed to the preservation of photoreceptors. Consequently, Qu pre-treatment holds promise as an effective strategy for controlling retinal inflammation and preserving visual function.
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Diabetic retinopathy is a common microvascular complication of diabetes and a leading cause of blindness. Pyroptosis has emerged as a mechanism of cell death involved in diabetic retinopathy pathology. This study explored the role of GSDME-mediated pyroptosis and its regulation by TNFSF15 in diabetic retinopathy. We found GSDME was upregulated in the progression of diabetic retinopathy. High glucose promoted GSDME-induced pyroptosis in retinal endothelial cells and retinal pigment epithelial cells, attributed to the activation of caspase-3 which cleaves GSDME to generate the pyroptosis-executing N-terminal fragment. TNFSF15 was identified as a binding partner and inhibitor of GSDME-mediated pyroptosis. TNFSF15 expression was increased by high glucose but suppressed by the caspase-3 activator Raptinal. Moreover, TNFSF15 protein inhibited high glucose- and Raptinal-induced pyroptosis by interacting with GSDME in retinal cells. Collectively, our results demonstrate TNFSF15 inhibits diabetic retinopathy progression by blocking GSDME-dependent pyroptosis of retinal cells, suggesting the TNFSF15-GSDME interaction as a promising therapeutic target for diabetic retinopathy.
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Ciclopentanos , Diabetes Mellitus , Retinopatia Diabética , Fluorenos , Humanos , Piroptose/fisiologia , Retinopatia Diabética/genética , Retinopatia Diabética/metabolismo , Caspase 3/metabolismo , Células Endoteliais/metabolismo , Glucose/metabolismo , Diabetes Mellitus/metabolismo , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismoRESUMO
The realization of multiferroic materials offers the possibility of multifunctional electronic device design. However, the coupling between the multiferroicity and piezoelectricity in Janus materials is rarely reported. In this study, we propose a mechanism for manipulating valley physics by magnetization reversing and ferroelectric switching in multiferroic and piezoelectric material. The ferromagnetic VSiGeP4 monolayer exhibits a large valley polarization up to 100 meV, which can be effectively operated by reversing magnetization. Interestingly, the antiferromagnetic VSiGeP4 bilayers with AB and BA stacking configurations allow the coexistence of valley polarization and ferroelectricity, supporting the proposed strategy for manipulating valley physics via ferroelectric switching and interlayer sliding. In addition, the VSiGeP4 monolayer contains remarkable tunable piezoelectricity regulated by electron correlation U. This study proposes a feasible idea for regulating valley polarization and a general design idea for multifunctional devices with multiferroic and piezoelectric properties, facilitating the miniaturization and integration of nanodevices.
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Heme oxygenase-1 (HO-1) catalyzes the first and rate-limiting enzymatic step of heme degradation, producing carbon monoxide, biliverdin, and free iron. Most iron is derived from aged erythrocytes by the decomposition of heme, which happened mainly in macrophages. However, the role of HO-1 on iron metabolism and function of macrophage is unclear. The present study investigated the effect of HO-1 on iron metabolism in macrophages, and explored the role of HO-1 on inflammatory response, polarization, and migration of macrophages. HO-1 inducer Hemin or HO-1 inhibitor zinc protoporphyrin was intravenously injected to C57BL/6 J mice every 4 d for 28 d. We found that HO-1 was mainly located in the cytoplasm of splenic macrophages of mice. Activation of HO-1 by Hemin significantly increased iron deposition in the spleen, up-regulated the gene expression of ferritin and ferroportin, and down-regulated gene expression of divalent metal transporter 1 and hepcidin. Induced HO-1 by Hemin treatment increased intracellular iron levels of macrophages, slowed down the absorption of extracellular iron, and accelerated the excretion of intracellular iron. In addition, activation of HO-1 significantly decreased the expression of pro-inflammatory cytokines including interleukin (IL)-6, IL-1ß, and inducible nitric oxide synthase, but increased the expression of anti-inflammatory cytokines such as IL-10. Furthermore, activation of HO-1 inhibited macrophages to M1-type polarization, and increased the migration rate of macrophages. This study demonstrated that HO-1 was able to regulate iron metabolism, exert anti-inflammatory effects, and inhibit macrophages polarization to M1 type.
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Heme Oxigenase-1 , Hemina , Camundongos , Animais , Heme Oxigenase-1/metabolismo , Hemina/farmacologia , Hemina/metabolismo , Ferro/metabolismo , Camundongos Endogâmicos C57BL , Macrófagos , Citocinas/metabolismo , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologiaRESUMO
OBJECTIVE: To assess the efficacy of subthreshold micropulse laser photocoagulation (SMLP) therapy versus anti-vascular endothelial growth factor (anti-VEGF) therapy in patients with refractory macular edema (ME) secondary to non-ischemic branch retinal vein occlusion (BRVO). METHODS: This single-center, prospective, nonrandomized, case-control trial involved patients with refractory ME that responded poorly to three or more initial anti-VEGF injections. The patients were examined and divided into two groups according to their chosen treatment: the intravitreal ranibizumab (IVR) group and the SMLP group. Both groups were followed up monthly for 12 months. Therapeutic efficacy and safety were assessed throughout the follow-up period. RESULTS: The IVR group comprised 49 eyes, and the SMLP group comprised 45 eyes. The improvements in the optical coherence tomography findings and visual acuity were comparable between the two groups at the final follow-up. The total number of injections was significantly lower in the SMLP than IVR group. No serious adverse events occurred during the study period. CONCLUSIONS: SMLP therapy is better for patients with central macular thickness (CMT) of ≤400 µm. For patients with CMT of >400 µm, we advise continuation of anti-VEGF agents to reduce ME followed by application of SMLP therapy when CMT has decreased to ≤400 µm.
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Edema Macular , Oclusão da Veia Retiniana , Humanos , Fatores de Crescimento Endotelial , Edema Macular/tratamento farmacológico , Edema Macular/etiologia , Oclusão da Veia Retiniana/complicações , Oclusão da Veia Retiniana/tratamento farmacológico , Estudos Prospectivos , Fotocoagulação , LasersRESUMO
Development of piezoelectric materials is limited partly due to the incompleteness of internal mechanism and the lack of vertical piezoelectricity. Herein, we theoretically identify the stable MoTO (T = S, Se, or Te) monolayers and bilayers. When two elements are given but another element can be changed, the larger the electronegativity difference ratio Rratio is, the stronger the piezoelectricity will be. Vertical piezoelectric coefficient d33 of the MoTeO bilayer reaches 38.907 pm/V, which is 12 times larger than that of the bulk GaN. The "active asymmetric electron-transfer" strategy mainly contributes to the spontaneous remarkable piezoelectricity of MoTO. Importantly, we proposed the new method for calculating the piezoelectric coefficients of two-dimensional (2D) materials, which corresponds to the fact that 2D materials have a certain thickness. This study not only provides novel extraordinary candidates for energy conversion and touch-sensor nanodevices but also promotes a deeper understanding of piezoelectricity of 2D materials.
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Background: Recent evidence shows that adipogenic differentiation of orbital fibroblasts (OFs) promotes the development of thyroid-associated ophthalmopathy (TAO), an organ-specific immune disease. Furthermore, miR-96-5p has been linked to adipogenic differentiation of C2C12 myoblasts and is significantly correlated with the severity of TAO. The purpose of this study is to look into the role of miR-96-5p in the adipogenesis of OFs with TAO. Methods: The orbital tissues from TAO patients and non-TAO participants were collected, and primary OFs were isolated and cultured for further analysis. miR-96-5p expression was examined using qRT-PCR. The adipogenic differentiation of OFs was then studied. Results: Orbital fibroblasts isolated from adipose tissues of TAO patients (t-OFs) demonstrated greater adipogenic differentiation ability than OFs isolated from adipose tissues of non-TAO participants. miR-96-5p was found to be overexpressed in the orbital tissues of TAO patients and t-OFs. Further research revealed that miR-96-5p, by targeting Smad7, could exacerbate PPAR-γ/C/EBPα signaling-induced adipogenic differentiation of t-OFs. However, inhibiting miR-96-5p could block t-OFs adipogenic differentiation-mediated adipogenesis via Smad7/PPAR-γ/C/EBPα. Conclusions: miR-96-5p plays a critical regulatory role in the development of TAO by targeting Smad7 and promoting adipogenic differentiation of OFs.
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18S, 5.8S, and 28S ribosomal RNAs (rRNAs) are cotranscribed as a pre-ribosomal RNA (pre-rRNA) from the rDNA by RNA polymerase I whose activity is vigorous during the S-phase, leading to a conflict with rDNA replication. This conflict is resolved partly by replication-fork-barrier (RFB)-sites sequences located downstream of the rDNA and RFB-binding proteins such as Ttf1. However, how Ttf1 is displaced from RFB-sites to allow replication fork progression remains elusive. Here, we reported that loss-of-function of Bms1l, a nucleolar GTPase, upregulates rDNA transcription, causes replication-fork stall, and arrests cell cycle at the S-to-G2 transition; however, the G1-to-S transition is constitutively active characterized by persisting DNA synthesis. Concomitantly, ubf, tif-IA, and taf1b marking rDNA transcription, Chk2, Rad51, and p53 marking DNA-damage response, and Rpa2, PCNA, Fen1, and Ttf1 marking replication fork stall are all highly elevated in bms1l mutants. We found that Bms1 interacts with Ttf1 in addition to Rc1l. Finally, we identified RFB-sites for zebrafish Ttf1 through chromatin immunoprecipitation sequencing and showed that Bms1 disassociates the Ttf1âRFB complex with its GTPase activity. We propose that Bms1 functions to balance rDNA transcription and replication at the S-phase through interaction with Rcl1 and Ttf1, respectively. TTF1 and Bms1 together might impose an S-phase checkpoint at the rDNA loci.
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GTP Fosfo-Hidrolases , Peixe-Zebra , Animais , Replicação do DNA , DNA Ribossômico/genética , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , RNA Polimerase I/metabolismo , RNA Ribossômico/genética , Peixe-Zebra/genéticaRESUMO
The first complete chloroplast genome (cpDNA) sequence of Brachypodium sylvaticum was determined from Illumina HiSeq pair-end sequencing data in this study. The cpDNA is 136,392 bp in length, contains a large single-copy region (LSC) of 80,854 bp and a small single-copy region (SSC) of 12,765 bp, which were separated by a pair of inverted repeats (IR) regions of 21,383 bp. The genome contains 130 genes, including 84 protein-coding genes, 8 ribosomal RNA genes, and 38 transfer RNA genes. Further phylogenomic analysis showed that B. sylvaticum and B. distachyon clustered in a unique clade in Brachypodium genus.
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Graves' ophthalmopathy, also known as thyroid-associated orbitopathy (TAO), is the most common inflammatory eye disease in adults. The most common etiology for TAO is Graves' disease (GD); however, proteomic research focusing on differences between GD and TAO is limited. This study aimed to identify differentially expressed proteins between thyroid-associated orbitopathy (TAO) and GD. Furthermore, we sought to explore the pathogenesis of TAO and elucidate the differentiation process via specific markers. Serum samples of three patients with TAO, GD, and healthy controls, respectively, were collected. These samples were measured using the iTRAQ technique coupled with mass spectrometry. Differentially expressed proteins in TAO and GD were identified by proteomics; 3172 quantified proteins were identified. Compared with TAO, we identified 110 differential proteins (27 proteins were upregulated and 83 were downregulated). In addition, these differentially expressed proteins were closely associated with cellular processes, metabolic processes, macromolecular complexes, signal transduction, and the immune system. The corresponding functions were protein, calcium ion, and nucleic acid binding. Among the differential proteins, MYH11, P4HB, and C4A were markedly upregulated in TAO patients and have been reported to participate in apoptosis, autophagy, the inflammatory response, and the immune system. A protein-protein interaction network analysis was performed. Proteomics demonstrated valuable large-scale protein-related information for expounding the pathogenic mechanism underlying TAO. This research provides new insights and potential targets for studying GD with TAO.
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Doença de Graves , Oftalmopatia de Graves , Adulto , Biomarcadores , Doença de Graves/complicações , Oftalmopatia de Graves/etiologia , Oftalmopatia de Graves/metabolismo , Humanos , Proteínas , Proteômica/métodosRESUMO
BACKGROUND: Insulin positively correlates with the length of the eye axis and is increased in the vitreous and serum of patients with pathological myopia (PM). How insulin influences the physiological process of retinal pigment epithelial (RPE) cells in PM remains unclear. This study aimed to explore the effect of insulin on the ultrastructure and function of RPE cells and the role of PI3K/AKT/mTOR signaling involved in the development of PM. METHODS: The ARPE-19 cells were treated with different concentrations of insulin to analyze the cell morphology, cell viability, the protein level of insulin receptor ß, and the mRNA and protein levels of and PM-related factors (TIMP-2, MMP-2, bFGF, and IGF-1). The ultrastructure of APRE-19 cells was also observed after insulin treatment. Besides, the PI3K/AKT/mTOR signaling was studied with or without the PI3K inhibitor LY294002 in ARPE-19 cells. RESULTS: Insulin enhanced the cell viability of ARPE-19 cells and caused the endoplasmic reticulum to expand and vesiculate, suggesting increased secretion of growth factors and degeneration in ARPE-19 cells. Furthermore, the insulin receptor ß was stimulated with insulin treatment, subsequently, the phosphorylation of AKT and mTOR was positively activated, which was adversely suppressed in the presence of LY294002. The secretion of TIMP-2 and bFGF was significantly decreased, and the secretion of MMP-2 and IGF-1 was highly elevated with insulin treatment depending on the concentration in ARPE-19 cells. Furthermore, the effect of insulin on PM-related proteins was restored with the addition of LY294002. CONCLUSIONS: Our results indicated that insulin regulated the secretion of PM-related factors via the PI3K/AKT/mTOR signaling pathway in retinal pigment epithelial cells, and thus probably promoted the development of PM through transducing regulation signals from retina to choroid and sclera.
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Miopia Degenerativa , Fosfatidilinositol 3-Quinases , Células Epiteliais/metabolismo , Humanos , Insulina , Proteínas Proto-Oncogênicas c-akt , Epitélio Pigmentado da Retina/metabolismo , Pigmentos da Retina , Transdução de Sinais , Serina-Treonina Quinases TORRESUMO
The aim of this study was to investigate the effects of polarization program on the ability of macrophages to regulate iron metabolism. M1 and M2 macrophages were propagated in vitro from porcine alveolar macrophages 3D4/2 and polarized by cytokines. The 3D4/2 macrophages were treated with 20 ng/mL interferon gamma (IFN-γ) and 10 ng/mL interleukin-4 (IL-4) combined with 10 ng/mL macrophage colony-stimulating factor (M-CSF) to induce polarization to M1 and M2, respectively. After incubation for 24 h, the expression levels of inflammatory factors and iron-metabolism genes were determined using real-time qPCR, Western bot and immunofluorescence. The M1/M2 macrophages culture media supernatant was collected and used to treat porcine intestinal epithelial cells IPEC-J2. The proliferation ability of IPEC-J2 was detected using CCK-8 assay kit. Following exogenous addition of ammonium ferric citrate (FAC) to M1/M2 macrophages, the phagocytic function of macrophages was detected using fluorescein isothiocyanate-dextran (FITC-dextran) and flow cytometry. The results showed that, compared with control, M1 macrophages had higher mRNA levels of iron storage proteins (ferritin heavy and light polypeptide, i.e. FtH and FtL), hepcidin and lipocalin-2, as well as iron content. Moreover, iron enhanced the ability of M1 macrophages to phagocytize FITC-dextran. There was no significant change in these mRNA expression levels in M2 macrophages, but the mRNA expression levels of ferroportin and transferrin receptor were up-regulated. In addition, the conditioned media supernatant from M2 macrophages promoted cell proliferation of IPEC-J2. These findings indicate that M1 macrophages tend to lock iron in the cell and reduce extracellular iron content, thereby inhibiting the proliferation of extracellular bacteria. While M2 macrophages tend to excrete iron, which contributes to the proliferation of surrounding cells and thus promotes tissue repair.
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Citocinas , Macrófagos , Animais , Ferritinas , Ferro/metabolismo , Macrófagos/metabolismo , Macrófagos Alveolares/metabolismo , SuínosRESUMO
Quantification of immuno-gold labeling can provide valuable information on the quantity and localization of a target within a region of interest (ROI). Background subtraction usually requires preparation of material with a deliberately reduced amount of target component often by gene knockout/knockdown. This paper reports a modified method without the need for gene knockout/knockdown, by using a region outside the ROI as a background and non-immune serum to verify the reliability of the data. An optimized parameter for use in image processing was also developed to improve semi-automatic segmentation of gold particles, by using the standard deviation of pixel intensity together with default parameters (size and intensity) to improve specificity. The modified methods were used to quantify the gold labeling of various components within chloroplasts and their 3 sub-organelle compartments (thylakoid, stroma and starch). Rubisco, actin, myosin, ß-tubulin, Endoplasmic reticulum-retention signal HDEL, Sterol methyltransferase 1, and double stranded RNA were all effectively and consistently quantified at the level of the different sub-chloroplast compartments. The approach should be applicable more widely for high resolution labelling of samples in which a background requiring gene knockout/knockdown is not a realistic option.
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Cloroplastos , Ouro , Organelas , Reprodutibilidade dos TestesRESUMO
The riparian zone is a river-land ecotone, and its environmental conditions have a significant effect on the river ecosystem and population health. In this study, As, Cu, Cr, Cd, Mn, Fe, Ni, Pb, and Zn in the topsoils of urban riparian zones in a subtropical city in southeast China were quantitatively estimated by inductively coupled plasma-optical emission spectrometry. The geoaccumulation index and health risk evaluation model were adopted to assess the accumulation characteristic and health risk of residents' exposure to metals. Principle component analysis was used to determine the source of metals. The results showed that the mean contents of metals (except Fe) were higher than the soil background value, but none of the metal contents exceeded the mass limit of environmental quality standards. The order of the geoaccumulation index was Cd > Mn > Cu > Cr > Pb > Zn > As > Ni > Fe. The contamination level of Cd was classified as slight, whereas the other metals did not contribute to pollution. The spatial distribution of metals in the riparian zone was compatible with the pattern of functional zones in the adjacent urban areas, where levels of Cr, Cd, Fe, Mn, and Ni were higher in commercial areas, as were Pb and Zn in under-construction land and As in residential and industrial areas. Carcinogenic risks of Cr, As, and Pb were acceptable. The hazard index indicated no significant noncarcinogenic risks from any metals. However, noncarcinogenic risks of metals other than Mn were higher for children than for adults, and the primary exposure route of metal into the human body was ingestion for children and inhalation for adults. Principle component analysis indicated that the primary sources of Cr, Ni, Mn, Cu, and Fe were pedogenic processes and mineral weathering, whereas Zn, As, Pb, and Cd mainly originated from anthropogenic sources, specifically, Zn from transportation emission, Pb from transportation emission and industry waste, As from coal combustion and residential waste, and Cd from pigments/paint used in commercial buildings, urban greening, consumer waste, and transportation emission.
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Metais Pesados , Poluentes do Solo , Adulto , Criança , China , Cidades , Ecossistema , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análiseRESUMO
The first complete chloroplast genome (cpDNA) sequence of Beckmannia syzigachne was determined from Illumina HiSeq pair-end sequencing data in this study. The cpDNA is 136,181 bp in length, contains a large single-copy region (LSC) of 80,345 bp and a small single-copy region (SSC) of 12,810 bp, which were separated by a pair of inverted repeats (IR) regions of 21,513 bp. The genome contains 132 genes, including 85 protein-coding genes, 8 ribosomal RNA genes, and 39 transfer RNA genes. Further phylogenomic analysis showed that B. syzigachne clustered in a unique clade in the Pooideae subfamily.