Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
1.
Appl Microbiol Biotechnol ; 108(1): 309, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38661971

RESUMO

An alpha-proteobacterial strain JXJ CY 53 T was isolated from the cyanosphere of Microcystis sp. FACHB-905 (MF-905) collected from Lake Dianchi, China. JXJ CY 53 T was observed to be an aerobic, Gram-stain-negative, oval shaped, and mucus-secreting bacterium. It had C18:1ω7c and C16:0 as the major cellular fatty acids, Q-10 as the predominant ubiquinone, and sphingoglycolipid, diphosphatidylglycerol, phosphatidylcholine, and phosphatidylmethylethanolamine as the polar lipids. The G + C content of DNA was 65.85%. The bacterium had 16S rRNA gene sequence identities of 98.9% and 98.7% with Sphingomonas panni DSM 15761 T and Sphingomonas hankookensis KCTC 22579 T, respectively, while less than 97.4% identities with other members of the genus. Further taxonomic analysis indicated that JXJ CY 53 T represented a new member of Sphingomonas, and the species epithet was proposed as Sphingomonas lacusdianchii sp. nov. (type strain JXJ CY 53 T = KCTC 72813 T = CGMCC 1.17657 T). JXJ CY 53 T promoted the growth of MF-905 by providing bio-available phosphorus and nitrogen, plant hormones, vitamins, and carotenoids. It could modulate the relative abundances of nonculturable bacteria associated with MF-905 and influence the interactions of MF-905 and other bacteria isolated from the cyanobacterium, in addition to microcystin production characteristics. Meanwhile, MF-905 could provide JXJ CY 53 T dissolved organic carbon for growth, and control the growth of JXJ CY 53 T by secreting specific chemicals other than microcystins. Overall, these results suggest that the interactions between Microcystis and its attached bacteria are complex and dynamic, and may influence the growth characteristics of the cyanobacterium. This study provided new ideas to understand the interactions between Microcystis and its attached bacteria. KEY POINTS: • A novel bacterium (JXJCY 53 T) was isolated from the cyanosphere of Microcystis sp. FACHB-905 (MF-905) • JXJCY 53 T modulated the growth and microcystin production of MF-905 • MF-905 could control the attached bacteria by specific chemicals other than microcystins (MCs).


Assuntos
Composição de Bases , DNA Bacteriano , Ácidos Graxos , Filogenia , RNA Ribossômico 16S , Sphingomonas , Sphingomonas/metabolismo , Sphingomonas/genética , Sphingomonas/isolamento & purificação , Sphingomonas/classificação , RNA Ribossômico 16S/genética , China , Ácidos Graxos/metabolismo , DNA Bacteriano/genética , Fosfolipídeos/análise , Microcystis/genética , Microcystis/metabolismo , Microcystis/crescimento & desenvolvimento , Lagos/microbiologia , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Simbiose , Ubiquinona
2.
Appl Environ Microbiol ; 88(13): e0069022, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35695487

RESUMO

High-throughput sequencing and high-pressure liquid chromatography (HPLC) methods were used to investigate the influences of microbial dynamics on the quality and biogenic amine (BA) content during fish sauce fermentation. The homogeneity of total viable bacteria and lactic acid bacteria in fish sauce becomes higher as fermentation progresses. Tetragenococcus was the key genus of fish sauce fermentation. Carnobacterium (38.43%) and Lentibacillus (41.01%) were the dominant genera in the samples fermented for 3 months and 18 months, respectively. These three bacterial genera were significantly related to the physicochemical characteristics and characteristic flavors of the sauces. Tetragenococcus was significantly positively correlated with nitrogen oxides, the main characteristic flavor components in fish sauce. The BA content in fish sauce fermentation increased from 106.88 to 376.03 mg/kg, and the content of histamine reached 115.30 mg/kg at the end of fermentation, indicating that fish sauce has health risks. About 66.67% of Lentibacillus isolates were able to produce a large amount of BA, suggesting that Lentibacillus was the key genus for BA accumulation in fish sauce fermentation. Research on reducing the content of BA in fish sauce by intervening with regard to the fermentation temperature showed that a safe fish sauce product could be obtained at the fermentation temperature of about 25°C. These results help us to understand the contribution of microbial community composition to fish sauce fermentation and provide a basis for improving the quality and safety of fermented fish sauce. IMPORTANCE Traditional fermentation of fish sauce is mainly carried out by complex microbial communities from raw anchovies and processing environments. However, it is still unclear how the environmental microbiota influences the quality and the safety of fish sauce products. Therefore, this study comprehensively explained the influence of microorganisms on the quality and safety of fish sauce during the fermentation process in terms of physicochemical characters, flavors, and BA. Additionally, the accumulation of BA in fish sauce fermentation was controlled by intervening in the fermentation temperature. This finding contributes to a deeper understanding of the role of environmental microbiota during fermentation and provides data support for improving the safety of fish sauce.


Assuntos
Aminas Biogênicas , Microbiologia de Alimentos , Animais , Bactérias/genética , Enterococcaceae , Fermentação , Produtos Pesqueiros/análise , Peixes/microbiologia
3.
Int J Mol Sci ; 23(19)2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36233264

RESUMO

Age-associated loss of skeletal muscle mass and function is one of the main causes of the loss of independence and physical incapacitation in the geriatric population. This study used the D-galactose-induced C2C12 myoblast aging model to explore whether nobiletin (Nob) could delay skeletal muscle aging and determine the associated mechanism. The results showed that Nob intervention improved mitochondrial function, increased ATP production, reduced reactive oxygen species (ROS) production, inhibited inflammation, and prevented apoptosis as well as aging. In addition, Nob improved autophagy function, removed misfolded proteins and damaged organelles, cleared ROS, reduced mitochondrial damage, and improved skeletal muscle atrophy. Moreover, our results illustrated that Nob can not only enhance mitochondrial function, but can also enhance autophagy function and the protein synthesis pathway to inhibit skeletal muscle atrophy. Therefore, Nob may be a potential candidate for the prevention and treatment of age-related muscle decline.


Assuntos
Galactose , Mitocôndrias , Trifosfato de Adenosina/metabolismo , Idoso , Envelhecimento/metabolismo , Senescência Celular , Flavonas , Galactose/efeitos adversos , Galactose/metabolismo , Humanos , Mitocôndrias/metabolismo , Músculo Esquelético/metabolismo , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo
4.
FASEB J ; 34(11)2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32896034

RESUMO

Renal fibrosis is the common pathological process of various chronic kidney diseases (CKD). Recent studies indicate that mitochondrial fragmentation is closely associated with renal fibrosis in CKD. However, the molecular mechanisms leading to mitochondrial fragmentation remain to be elucidated. The present study investigated the role of regulators of calcineurin 1 (RCAN1) in mitochondrial fission and renal interstitial fibrosis using conditional knockout mice in which RCAN1 was genetically deleted in tubular epithelial cells (TECs). TEC-specific deletion of RCAN1 attenuated tubulointerstitial fibrosis and epithelial to mesenchymal transition (EMT)-like phenotype change after unilateral ureteral obstruction (UUO) and ischemia reperfusion injury (IRI) through suppressing TGF-ß1/Smad3 signaling pathway. TEC-specific deletion of RCAN1 also reduced the tubular apoptosis after UUO by inhibiting cytochrome c/caspase-9 pathway. Ultrastructure analysis revealed a marked decrease in mitochondrial fragmentation in TECs of RCAN1-deficient mice in experimental CKD models. The expression of mitochondrial profission proteins dynamin-related protein 1 (Drp1) and mitochondrial fission factor (Mff) was also downregulated in obstructed kidney of TEC-specific RCAN1-deficient mice. Furthermore, TEC-specific deletion of RCAN1 attenuated the dysfunctional tubular autophagy by regulating PINK1/Parkin-induced mitophagy in CKD. RCAN1 knockdown and knockout similarly improved the mitochondrial quality control in HK-2 cells and primary cultured mouse tubular cells stimulated by TGF-ß1. Put together, our data indicated that RCAN1 plays an important role in the progression of tubulointerstitial fibrosis through regulating the mitochondrial quality. Therefore, targeting RCAN1 may provide a potential therapeutic approach in CKD.


Assuntos
Proteínas de Ligação ao Cálcio/fisiologia , Fibrose/prevenção & controle , Nefropatias/prevenção & controle , Mitocôndrias/fisiologia , Proteínas Musculares/fisiologia , Traumatismo por Reperfusão/complicações , Obstrução Ureteral/complicações , Animais , Apoptose , Transição Epitelial-Mesenquimal , Fibrose/etiologia , Fibrose/patologia , Humanos , Nefropatias/etiologia , Nefropatias/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais , Fator de Crescimento Transformador beta1/metabolismo
5.
Mol Pharm ; 18(9): 3601-3615, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34388342

RESUMO

Chlorin e6 (Ce6) is a promising photosensitizer for tumor photodynamic therapy (PDT). However, the efficacy of Ce6 PDT is limited by Ce6's poor water solubility, rapid blood clearance, and inadequate accumulation in the tumor tissue. This problem is tackled in this work, wherein functionalized superparamagnetic iron oxide nanoparticles (IO-NPs) were used as carriers to deliver Ce6 to melanoma. The IO-NPs were coated with polyglycerol (PG) to afford good aqueous solubility. The chemotherapeutic agent doxorubicin (DOX) was attached to the PG coating via the hydrazone bond to afford affinity to the cell membrane and thereby promote the cell uptake. The hydrophobic nature of DOX also induced the aggregation of IO-NPs to form nanoclusters. Ce6 was then loaded onto the IO nanoclusters through physical adsorption and coordination with surface iron atoms, yielding the final composites IO-PG-DOX-Ce6. In vitro experiments showed that IO-PG-DOX-Ce6 markedly increased Ce6 uptake in mouse melanoma cells, leading to much-enhanced photocytotoxicity characterized by intensified reactive oxygen species production, loss of viability, DNA damage, and stimulation of tumor cell immunogenicity. In vivo experiments corroborated the in vitro findings and demonstrated prolonged blood clearance of IO-PG-DOX-Ce6. Importantly, IO-PG-DOX-Ce6 markedly increased the Ce6 distribution and retention in mouse subcutaneous melanoma grafts and significantly improved the efficacy of Ce6-mediated PDT. No apparent vital organ damage was observed at the same time. In conclusion, the IO-PG-DOX NPs provide a simple and safe delivery platform for efficient tumor enrichment of Ce6, thereby enhancing antimelanoma PDT.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Clorofilídeos/administração & dosagem , Melanoma/tratamento farmacológico , Sistemas de Liberação de Fármacos por Nanopartículas/química , Neoplasias Cutâneas/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/química , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Linhagem Celular Tumoral , Clorofilídeos/química , Clorofilídeos/farmacocinética , Modelos Animais de Doenças , Doxorrubicina/administração & dosagem , Feminino , Humanos , Nanopartículas Magnéticas de Óxido de Ferro/química , Melanoma/patologia , Camundongos , Fotoquimioterapia , Neoplasias Cutâneas/patologia , Solubilidade , Distribuição Tecidual
6.
Appl Microbiol Biotechnol ; 104(17): 7457-7465, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32676711

RESUMO

The serp gene codes for a protease that is considered to be an important factor associated with quorum sensing (QS)-based food spoilage caused by microorganisms. In this study, we evaluated the effect of temperature (4-37 °C) and QS inhibitors on the production of N-acyl-L-homoserine lactones (AHLs) and relative expression of the luxR/I, as well as serp in Hafnia alvei H4. Production of AHLs and expression of luxR/I were found to reach maximum levels at 10 °C, suggesting that the QS system of H. alvei H4 might have higher activity at low temperatures; similar result was also obtained for serp expression. Mutants of H. alvei H4 deficient in QS were used to identify the regulation of QS on serp expression. Significant reduction (P < 0.05) in serp expression was found in the mutants ∆luxR, ∆luxI, and ∆luxR/I, with ∆luxI and ∆luxR/I showing greater reduction than ∆luxR. Minimum inhibition concentrations (MIC) of Benzyl isothiocyanate and 3-Methylthiopropyl isothiocyanate for H. alvei H4 were determined to be 7.813 and 15.625 mM, respectively. Furthermore, the expression of serp, as well as that of luxR and luxI, was significantly repressed (P < 0.05) by the two QS inhibitors at 1/8 MIC and 1/16 MIC, indicating that these inhibitors might repress serp expression through affecting luxR and luxI expression in H. alvei H4. The findings of this study, therefore, suggested that food spoilage caused by H. alvei could be controlled through the application of QS inhibitors.


Assuntos
Hafnia alvei , Percepção de Quorum , Acil-Butirolactonas , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Hafnia alvei/metabolismo , Serina , Serina Proteases
7.
Curr Microbiol ; 77(9): 1997-2001, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32754853

RESUMO

A Gram-positive, aerobic, motile and short rod-shaped bacterium, designated as strain G56T, was isolated from shrimp paste produced in Panjin, China. Grows in the presence of 1.0-25.0% (w/v) NaCl (optimum at 10%), pH 5.0-9.5 (optimally at 7.0) and 10-50 °C (optimally at 37 °C). Positive for catalase and oxidase activities, but lack the ability to reduce nitrate. Acids produce from D-ribose, D-xylose, D-galactose, glycerol and D-trehalose, but no acid is produced when salicin, D-mannose, D-cellobiose and L-sorbose are provided as substrates. The polar lipid extract is found to contain diphosphatidylglycerol, phosphatidylglycerol, an unknown glycolipid, and unidentified phospholipids. Fatty acids are mainly defined as anteiso-C15:0 (69.7%) and anteiso-C17:0 (23.3%). The G+C content of its DNA is 44.7 mol%. The draft genome of strain G56T is 3,209,087 bp in length and the average nucleotide identity value (ANI) and the digital DNA-DNA hybridization (DDH) values between strain G56T and L. juripiscarius JCM 12147T is 78.41% and 22.0%, respectively. Polyphasic taxonomic analysis classified strain G56T as a novel species in the genus Lentibacillus, and therefore, we named it as Lentibacillus panjinensis sp. nov..


Assuntos
Alimentos Fermentados , Fosfolipídeos , Técnicas de Tipagem Bacteriana , China , DNA Bacteriano/genética , Ácidos Graxos , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
8.
Zhongguo Zhong Yao Za Zhi ; 40(24): 4817-23, 2015 Dec.
Artigo em Zh | MEDLINE | ID: mdl-27245028

RESUMO

Moderate drought stress has been found to promote the accumulation of active ingredients in Glycyrrhiza uralensis root and hence improve the medicinal quality. In this study, the transcriptomes of 6-month-old moderate drought stressed and control G. uralensis root (the relative water content in soil was 40%-45% and 70%-75%, respectively) were sequenced using Illumina HiSeq 2000. A total of 80,490 490 and 82 588 278 clean reads, 94,828 and 305,100 unigenes with N50 sequence of 1,007 and 1,125 nt were obtained in drought treated and control transcriptome, respectively. Differentially expressed genes analysis revealed that the genes of some cell wall enzymes such as ß-xylosidase, legumain and GDP-L-fucose synthase were down-regulated indicating that moderate drought stress might inhibit the primary cell wall degradation and programmed cell death in root cells. The genes of some key enzymes involved in terpenoid and flavonoid biosynthesis were up-regulated by moderate drought stress might be the reason for the enhancement for the active ingredients accumulation in G. uralensis root. The promotion of the biosynthesis and signal transduction of auxin, ethylene and cytokinins by moderate drought stress might enhance the root formation and cell proliferation. The promotion of the biosynthesis and signal transduction of abscisic acid and jasmonic acid by moderate drought stress might enhance the drought stress tolerance in G. uralensis. The inhibition of the biosynthesis and signal transduction of gibberellin and brassinolide by moderate drought stress might retard the shoot growth in G. uralensis.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Glycyrrhiza uralensis/genética , Transcriptoma , Raízes de Plantas , Análise de Sequência de DNA , Estresse Fisiológico
9.
Zhongguo Zhong Yao Za Zhi ; 38(9): 1344-8, 2013 May.
Artigo em Zh | MEDLINE | ID: mdl-23944066

RESUMO

OBJECTIVE: To explore the quality variation and genetic diversity of Desmodium styracifolium from different provenances, and lay a foundation for rational exploitation on germplasm resources and fine variety breeding of D. styracifolium. METHOD: Amplified fragment length polymorphism (AFLP) markers were developed to analyze genetic diversity in D. styracifolium from 18 resources. NTSYSpc-2. 11F software was used to analyze the similarity among the D. styracifolium germplasms and construct the genetic phylogenetic tree. The schaftoside content in D. styracifolium from different provenances was determined by HPLC. RESULT: A total of 844 fragments were amplified with 8 primers, in which 717 were polymorphic bands, accounting for 84. 27% of the total detected variation. All the specimens from 18 resources could be grouped into 3 clusters by cluster analysis. The schaftoside contents of D. styracifolium germplasms differed significantly, with the highest content in the germplasm from Sanya, Hainan. CONCLUSION: Significant quality variation and genetic diversity can be observed among D. styracifolium germplasms. The diverse germplasm resources should be explored and the fine variety should be selected to breed.


Assuntos
Fabaceae/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Fabaceae/classificação , Variação Genética/genética
10.
Food Res Int ; 169: 112872, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37254322

RESUMO

This study aimed to understand the structural, digestion and fecal fermentation behaviors of sea cucumber polysaccharide fermented by Bacillus subtilis Natto. Results showed that both sea cucumber polysaccharide (SP) and fermented sea cucumber polysaccharide (FSP) were sulfated polysaccharides mainly containing fucose. The physicochemical property, molecular weight, thermal property, and functional groups were no significant difference between SP and FSP, but the microscopic morphology and monosaccharide composition of FSP changed. Both SP and FSP showed similar digestion and fecal fermentation characteristics, that is, they could not be digested by saliva and gastric juice, but could be partially degraded by small intestine. Due to the decomposition of glycosidic bonds after intestinal digestion and fecal fermentation, the relative molecular mass of SP and FSP decreased. In terms of impacts on gut microbiota, Lachnospira, Bacteroides finegoldii, and Bifidobacteriaceae were significantly increased in SP, while Acinetobacter was significantly increased in FSP. This study provides a good understanding of the changes in the structure and digestive characteristics of sea cucumber polysaccharides caused by fermentation. That information will be beneficial for the development and application of new fermented sea cucumber products.


Assuntos
Microbioma Gastrointestinal , Pepinos-do-Mar , Alimentos de Soja , Animais , Bacillus subtilis/metabolismo , Polissacarídeos/química
11.
Nutrients ; 15(8)2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37111020

RESUMO

Sarcopenia, a decrease in skeletal muscle mass and function caused by aging, impairs mobility, raises the risk of fractures, diabetes, and other illnesses, and severely affects a senior's quality of life. Nobiletin (Nob), polymethoxyl flavonoid, has various biological effects, such as anti-diabetic, anti-atherogenic, anti-inflammatory, anti-oxidative, and anti-tumor properties. In this investigation, we hypothesized that Nob potentially regulates protein homeostasis to prevent and treat sarcopenia. To investigate whether Nob could block skeletal muscle atrophy and elucidate its underlying molecular mechanism, we used the D-galactose-induced (D-gal-induced) C57BL/6J mice for 10 weeks to establish a skeletal muscle atrophy model. The findings demonstrated that Nob increased body weight, hindlimb muscle mass, lean mass and improved the function of skeletal muscle in D-gal-induced aging mice. Nob improved myofiber sizes and increased skeletal muscle main proteins composition in D-gal-induced aging mice. Notably, Nob activated mTOR/Akt signaling to increase protein synthesis and inhibited FOXO3a-MAFbx/MuRF1 pathway and inflammatory cytokines, thereby reducing protein degradation in D-gal-induced aging mice. In conclusion, Nob attenuated D-gal-induced skeletal muscle atrophy. It is a promising candidate for preventing and treating age-associated atrophy of skeletal muscles.


Assuntos
Galactose , Sarcopenia , Camundongos , Animais , Galactose/metabolismo , Sarcopenia/metabolismo , Proteostase , Qualidade de Vida , Camundongos Endogâmicos C57BL , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/tratamento farmacológico , Atrofia Muscular/metabolismo , Músculo Esquelético/metabolismo , Envelhecimento
12.
Food Res Int ; 173(Pt 1): 113276, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803588

RESUMO

Bagging is an effective cultivation strategy to produce attractive and pollution-free kiwifruit. However, the effect and metabolic regulatory mechanism of bagging treatment on kiwifruit quality remain unclear. In this study, transcriptome and metabolome analyses were conducted to determine the regulatory network of the differential metabolites and genes after bagging. Using outer and inner yellow single-layer fruit bags, we found that bagging treatment improved the appearance of kiwifruit, increased the soluble solid content (SSC) and carotenoid and anthocyanin levels, and decreased the chlorophyll levels. We also identified 41 differentially expressed metabolites and 897 differentially expressed genes (DEGs) between the bagged and control 'Hongyang' fruit. Transcriptome and metabolome analyses revealed that the increase in SSC after bagging treatment was mainly due to the increase in D-glucosamine metabolite levels and eight DEGs involved in amino sugar and nucleotide sugar metabolic pathways. A decrease in glutamyl-tRNA reductase may be the main reason for the decrease in chlorophyll. Downregulation of lycopene epsilon cyclase and 9-cis-epoxycarotenoid dioxygenase increased carotenoid levels. Additionally, an increase in the levels of the taxifolin-3'-O-glucoside metabolite, flavonoid 3'-monooxygenase, and some transcription factors led to the increase in anthocyanin levels. This study provides novel insights into the effects of bagging on the appearance and internal quality of kiwifruit and enriches our theoretical knowledge on the regulation of color pigment synthesis in kiwifruit.


Assuntos
Actinidia , Transcriptoma , Frutas/genética , Frutas/metabolismo , Antocianinas/metabolismo , Metaboloma , Actinidia/genética , Actinidia/metabolismo , Carotenoides/metabolismo , Clorofila
13.
Environ Sci Technol ; 46(6): 3312-8, 2012 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-22313249

RESUMO

A new method for stable carbon isotope ratio analysis of anhydrosugars from biomass burning aerosol particle source filter samples was developed by employing Thermal Desorption--2 Dimensional Gas Chromatography--Isotope Ratio Mass Spectrometry (TD-2DGC-IRMS). Compound specific isotopic measurements of levoglucosan, mannosan, and galactosan performed by TD-2DGC-IRMS in a standard mixture show good agreement with isotopic measurements of the bulk anhydrosugars, carried out by Elemental Analyzer--Isotope Ratio Mass Spectrometry (EA-IRMS). The established method was applied to determine the isotope ratios of levoglucosan, mannosan, and galactosan from source samples collected during combustion of hard wood, softwood, and crop residues. δ(13)C values of levoglucosan were found to vary between -25.6 and -22.2‰, being higher in the case of softwood. Mannosan and galactosan were detected only in the softwood samples showing isotope ratios of -23.5‰ (mannosan) and -25.7‰ (galactosan). The isotopic composition of holocellulose in the plant material used for combustion experiments was determined with δ(13)C values between -28.5 and -23.7‰. The difference in δ(13)C of levoglucosan in biomass burning aerosol particles compared to the parent fuel holocellulose was found to be -1.89 (±0.37)‰ for the investigated biomass fuels. Compound specific δ(13)C measurements of anhydrosugars should contribute to an improved source apportionment.


Assuntos
Poluentes Atmosféricos/análise , Isótopos de Carbono/análise , Hexoses/análise , Material Particulado/análise , Aerossóis , Biomassa , Cycadopsida , Temperatura Alta , Magnoliopsida
14.
Environ Monit Assess ; 184(10): 5957-70, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22170156

RESUMO

The characteristics and sources of major hydrocarbons and halocarbons in the wintertime ambient air of urban center of Shanghai, a mega city of China, were investigated. Propane, toluene, ethyl acetate, and benzene were the most abundant hydrocarbons. The majority of species showed significant variability in mixing ratios with occasional episodic increases. The more common use of liquefied petroleum gas fuel for taxis and light motorcycles was believed to lead to high levels of ambient propane over the urban center of Shanghai. Correlating with toluene, dichloromethane, and 1,2-dichloroethane (1,2-DCE), abundant chloromethane (up to a daily mean of 1.61 ± 0.99 ppbv and a maximum of 5.34 ppbv) was mainly associated with industrial emissions, although biomass burnings exist widely in east China. The Chinese New Year (CNY) holiday period with no industrial activity over China provides a platform for the study of industrial emissions over the urban atmosphere of Shanghai. The normal weekly cycles were characterized by higher and more variable mixing ratios during weekdays which dropped during weekends. Enhanced mixing ratios were observed in the fortnight before the CNY holidays due to increased industrial emissions as a result of overtime production to make up for the holiday losses. During the CNY holidays, lower level and less variable mixing ratios were observed. A benzene/toluene (B/T) ratio of 0.6 ± 0.4 (mean ± std.) for the morning rush hour samples was identified to be the characteristic ratio of vehicular emissions. However, a B/T ratio of 0.4 ± 0.2 from vehicles and other sources was derived for the ambient air.


Assuntos
Poluentes Atmosféricos/análise , Atmosfera/química , Monitoramento Ambiental , Tolueno/análise , Acetatos/análise , Poluição do Ar/estatística & dados numéricos , Benzeno/análise , China , Cidades/estatística & dados numéricos , Hidrocarbonetos , Estações do Ano , Emissões de Veículos/análise
15.
Front Microbiol ; 12: 628838, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33584630

RESUMO

The bacterial profiles of 63 grasshopper sub shrimp paste samples collected from seven typical regions around the Bohai Sea were investigated by high-throughput sequencing. Tetragenococcus muriaticus was found to be the prevailing species present in all the samples, and the presence of T. muriaticus also weakly correlated with the histamine content in the samples. Six T. muriaticus strains with low biogenic amine (BA)-producing ability and deficient in histamine production were identified and subjected to safety assessment. All six strains displayed weak resistance to fifteen known antibiotics as based on the Enterococcus breakpoint values. None of the strains exhibited hemolytic activity or biofilm formation. All strains exhibited were able to grow on MRS agar containing 21% NaCl and expressed amine oxidase and strain-specific proteases and lipases. Most of the strains exhibited acid production at 18% NaCl. Moreover, three of the strains (designated as SG, TS, and QH) with histamine degradation ability were inoculated into separate shrimp paste samples to determine their effect on BA accumulation. The results indicated that the addition of T. muriaticus to shrimp pastes not only led to a significant reduction of BA content in the pastes but also improved the flavor of the pastes. Consequently, these strains may be used as potential candidates for controlling the content of histamine in fermented foods.

16.
AMB Express ; 11(1): 25, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33569734

RESUMO

Controlling the content of biogenic amines (BAs) is critical to guarantee the safety of fermented aquatic products. The degradation characteristics and application potential of amine-negative starter cultures (Virgibacillus halodenitrificans CGMCC 1.18601: G25, Virgibacillus pantothenticus CGMCC 1.18602: G38) screened from grasshopper sub shrimp paste (Gssp) were studied. The enzymes of the two strains G25 and G38 that degrade BAs were amine oxidases (AOs) located on their respective cell membranes. The conditions that promoted the AO activity of Virgibacillus spp. were NaCl concentrations 5-10%, temperature 37 °C, pH 7.0 and ethanol concentrations 0-2%. Safety assessments (antibiotic susceptibility, biofilm activity and hemolytic activity) indicated that Virgibacillus spp. do not present a risk to human health, and this isolate can be confidently recommended as safe starter cultures for the food industry. Then, the two strains were cultured separately as starters and applied to the Gssp to analyze their influence on the flavor and quality of the product. As far as the bad flavors in Gssp such as sulfur-organic and sulf-chlor were concerned, the response values in the starter groups by G25 and G38 were significantly reduced by 39% and 65%, respectively. For the ability of strains to degrade BAs in Gssp, G25 degraded 11.1% of histamine, 11.3% of tyramine, 15.5% of putrescine and 4.1% of cadaverine; G38 significantly degraded 10.1% of histamine, 21.8% of tyramine, 18.1% of putrescine and 5.0% of cadaverine. These results indicated that the selected species could be used as starter cultures for the control of BA accumulation and degradation in Gssp.

17.
Int Immunopharmacol ; 100: 108164, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34562845

RESUMO

Photodynamic therapy (PDT) is an emerging anti-tumor strategy.Photosensitizer chlorin e6 (Ce6) can induce photodynamic effect to selectively damage lung cancer cells.In order to further improve its tumor targeting ability, macrophages can be applied as carrier to deliver Ce6 to lung cancer.Tumor associated macrophages (TAM) are important immunocytes in lung cancer immune microenvironment. TAM play crucial role in tumor promotion due to the Immunosuppressive property, reprogramming phenotype of TAM therefore has become a promising strategy.Based on this, in the present study, we suppose that TAM can be used as carrier to deliver Ce6 to lung cancer and be reprogrammed to M1 phenotype by photodynamic action to mediate anti-lung cancer efficacy.The results showed TAM could load with Ce6 and keep viability in the absence of near infrared irradiation (NIR).Moreover, Its viability decreased little within 10 h after NIR.Ce6-loaded TAM could deliver Ce6 to lung cancer cells and retain some drugs in TAM per se.After NIR, phagocytosis of macrophages was enhanced. The expressions of GBP5, iNOS and MHC-II was up-regulated, which indicated TAM were polarized to M1 phenotype.Finally, the study also found the reprogrammed macrophages could inhibit the proliferation and promote the apoptosis of lung cancer cells.These results suggested that macrophages could deliver Ce6 to lung cancer and exhibit anti-lung cancer effect through photodynamic reprogramming.This study provides a novel approach for combining photodynamic action with anti-tumor immunotherapy.


Assuntos
Carcinoma Pulmonar de Lewis/tratamento farmacológico , Clorofilídeos/farmacologia , Imunoterapia , Neoplasias Pulmonares/tratamento farmacológico , Fotoquimioterapia , Radiossensibilizantes/farmacologia , Macrófagos Associados a Tumor/metabolismo , Animais , Apoptose , Carcinoma Pulmonar de Lewis/imunologia , Carcinoma Pulmonar de Lewis/metabolismo , Carcinoma Pulmonar de Lewis/patologia , Linhagem Celular Tumoral , Proliferação de Células , Clorofilídeos/metabolismo , Técnicas de Cocultura , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Fagocitose , Fenótipo , Células RAW 264.7 , Radiossensibilizantes/metabolismo , Microambiente Tumoral , Macrófagos Associados a Tumor/imunologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-32766221

RESUMO

OBJECTIVE: To explore the effects of SnO2 nanoparticles (NPs) on proliferation, invasion, apoptosis, and oxidative stress of oral cancer. METHODS: SnO2 NPs were prepared and characterized. Oral cancer cell lines CAL-27 and SCC-9 were cultured in vitro. We detected the effects of various concentrations of SnO2 NPs (0, 5, 25, 50, 100, 200 µg/mL) on the proliferation of oral cancer cells, and observed the morphological changes, and measured the cells ability of migration, invasion and apoptosis condition, and the levels of oxidative stress were measured by detecting malondialdehyde (MDA) and reactive oxygen species (ROS). Besides, we also measured the changes of mRNA and protein levels of factors related to cell proliferation, migration, invasion, apoptosis, and oxidative stress. RESULTS: SnO2 NPs inhibited the proliferation of oral cancer cells in a concentration-dependent manner (all P < 0.05). And SnO2 NPs treatment could reduce the migration and invasion ability of cells (all P < 0.05), induce apoptosis, and those effects were better when treated for 48 h than 24 h (all P < 0.05). And SnO2 NPs could induce oxidative stress in cells (all P < 0.05). Besides, the concentrations of cyclin-D1, C-myc, matrix MMP-9, and MMP-2 in SnO2 NPs treated group was decreased (all P < 0.05), and the expression levels of cleaved Caspase-3, cleaved Caspase-9, and Cytochrome C were increased (all P < 0.05). CONCLUSION: In the present study, we found that SnO2 NPs could play a cytotoxic role in oral cancer cells, and inhibit cell proliferation, migration, and invasion, and induce oxidative stress and apoptosis, which suggests that SnO2 NPs may have the effects of anti-oral cancer. However, a more in-depth study is needed to determine its roles.

19.
Front Microbiol ; 11: 782, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32390997

RESUMO

Biogenic amines (BAs) and microbial diversity are important factors affecting food quality and safety in fermented foods. In this study, the bacterial and fungal diversity in grasshopper sub shrimp paste taken at different fermentation times were comprehensively analyzed, while the pH, colony counts, salinity, total volatile base nitrogen (TVB-N) and BA contents were quantitatively determined. In addition, the correlations among the samples with respect to microbial communities and the different parameters investigated especially BAs were also established. By combining the results of spearman correlation heatmap with the contents of BAs produced by the 102 halotolerant bacteria isolated from the grasshopper sub shrimp paste, six major genera of bacteria (Jeotgalibaca, Jeotgalicoccus, Lysinibacillus, Sporosarcina, Staphylococcus, and Psychrobacter) were found to be positively correlated with BA production level, suggesting that these bacteria might have a strong tendency to produce BAs. Other bacteria such as Lentibacillus, Pseudomonas, and Salinicoccus were considered as poor BA producers. The grasshopper sub shrimp paste was characterized by a relatively high abundance of Tetragenococcus, which was the dominant genus during the fermentation process, and it also produced a relatively high level of BAs but the spearman correlation heatmap revealed a negative correlation between T. muriaticus and BA level. Analysis of the species relevance network in grasshopper sub shrimp explained that the actual production of BAs by a certain strain was closely related to other species present in the complex fermentation system.

20.
Biosci Rep ; 40(1)2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31894838

RESUMO

High glucose (HG)-induced mitochondrial dynamic changes and oxidative damage are closely related to the development and progression of diabetic kidney disease (DKD). Recent studies suggest that regulators of calcineurin 1 (RCAN1) is involved in the regulation of mitochondrial function in different cell types, so we investigate the role of RCAN1 in mitochondrial dynamics under HG ambience in rat glomerular mesangial cells (MCs). MCs subjected to HG exhibited an isoform-specific up-regulation of RCAN1.4 at both mRNA and protein levels. RCAN1.4 overexpression induced translocation of Dynamin related protein 1 (Drp1) to mitochondria, mitochondrial fragmentation and depolarization, accompanied by increased matrix production under normal glucose and HG ambience. In contrast, decreasing the expression of RCAN1.4 by siRNA inhibited HG-induced mitochondrial fragmentation and matrix protein up-regulation. Moreover, both mitochondrial fission inhibitor Mdivi-1 and Drp1 shRNA prevented RCAN1.4-induced fibronectin up-regulation, suggesting that RCAN1.4-induced matrix production is dependent on its modulation of mitochondrial fission. Although HG-induced RCAN1.4 up-regulation was achieved by activating calcineurin, RCAN1.4-mediated mitochondrial fragmentation and matrix production is independent of calcineurin activity. These results provide the first evidence for the HG-induced RCAN1.4 up-regulation involving increased mitochondrial fragmentation, leading to matrix protein up-regulation.


Assuntos
Matriz Extracelular/efeitos dos fármacos , Glucose/toxicidade , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células Mesangiais/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Dinâmica Mitocondrial/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Animais , Calcineurina/metabolismo , Células Cultivadas , Dinaminas/genética , Dinaminas/metabolismo , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Células Mesangiais/metabolismo , Células Mesangiais/patologia , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Regulação para Cima
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA