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1.
Dermatol Surg ; 50(6): 542-545, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38460194

RESUMO

BACKGROUND: The Tessari method is commonly used in sclerotherapy for producing foam, involving 2 syringes pushed back and forth 20 times with the use of a 3-way connector. Many factors affect the foam stability which is crucial for clinical efficacy. OBJECTIVE: This study aimed to identify the optimal pushing rate which may impact the foam stability. MATERIALS AND METHODS: Polidocanol (POL) solution (1% and 3%) was used to make sclerosant foam via the Tessari method, with a total of 20 pushes performed at different time durations: 10, 15, 20, 25, 30, 35, and 40 seconds. The foam stability was recorded using foam half-life time (FHT), and the pushing pressure to the syringe was recorded using a self-made electric device. Both FHT and the pressure among different groups were compared respectively. RESULTS: The FHT was decreased as pushing duration exceeding 20 seconds in POL 1% and 15 seconds in POL 3%. Both the highest FHT and pressure point were located in the 10-second group. CONCLUSION: It is recommended to complete 20 back-and-forth passages within 10 seconds to create stable foam.


Assuntos
Polidocanol , Soluções Esclerosantes , Escleroterapia , Seringas , Soluções Esclerosantes/química , Soluções Esclerosantes/administração & dosagem , Polidocanol/química , Polidocanol/administração & dosagem , Escleroterapia/métodos , Polietilenoglicóis/química , Pressão , Estabilidade de Medicamentos , Humanos , Fatores de Tempo , Meia-Vida
2.
J Environ Manage ; 354: 120337, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38417357

RESUMO

China, being a major agricultural nation, employs aerobic composting as an efficient approach to handle agricultural solid waste. Nevertheless, the composting process is often accompanied by greenhouse gas emissions, which are known contributors to global warming. Therefore, it is urgent to control the formation and emission of greenhouse gases from composting. This study provides a comprehensive analysis of the mechanisms underlying the production of nitrous oxide, methane, and carbon dioxide during the composting process of agricultural wastes. Additionally, it proposes an overview of the variables that affect greenhouse gas emissions, including the types of agricultural wastes (straw, livestock manure), the specifications for compost (pile size, aeration). The key factors of greenhouse gas emissions during composting process like physicochemical parameters, additives, and specific composting techniques (reuse of mature compost products, ultra-high-temperature composting, and electric-field-assisted composting) are summarized. Finally, it suggests directions and perspectives for future research. This study establishes a theoretical foundation for achieving carbon neutrality and promoting environmentally-friendly composting practices.


Assuntos
Compostagem , Gases de Efeito Estufa , Gases de Efeito Estufa/análise , Agricultura , Dióxido de Carbono/análise , Aquecimento Global , Metano/análise , Óxido Nitroso/análise , Esterco/análise , Solo
3.
Environ Res ; 224: 115447, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36758919

RESUMO

A green, high-efficiency, and wide pH tolerance water remediation process has been urgently acquired for the increasingly exacerbating contaminated water. In this study, a Fe3+/persulfate (Fe3+/PS) system was employed and enhanced with a green natural ligand cysteine (Cys) for the degradation of quinclorac (QNC). The introduction of Cys into the Fe3+/PS system widened the effective pH range to 9 with a superior removal rate for QNC. The mechanism revealed that the Fe3+/Cys/PS system can enhance the ability of degrading QNC by accelerating the Fe3+/Fe2+ redox cycle, maintaining Fe2+ concentration and thereby generating more HO• and SO4•-. The impact factors (i.e., pH, concentrations of PS, Fe3+ and Cys) were optimized as well. This work provides a promising strategy with high catalytic activity and wide pH tolerance for organic contaminated water remediation.


Assuntos
Quinolinas , Poluentes Químicos da Água , Purificação da Água , Cisteína/química , Concentração de Íons de Hidrogênio , Oxirredução , Água , Poluentes Químicos da Água/análise , Química Verde
4.
Ecotoxicology ; 31(6): 873-883, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35834074

RESUMO

Nanoscale zero-valent iron particles (NZVI) are widely used in a variety of industries owing to their advantageous mechanical, physical, and chemical properties. These particles can be released into environmental media, including water, soil, and air, through several pathways. NZVI in the ecosystem can be taken up, excreted and distributed within organisms, which is harmful to plants, animals and humans. Plants play a significant role as producers in the ecological circle and can both positively and negatively affect the ecological behavior of NZVI. Therefore, understanding the relationship between plants and NZVI is likely to be of great value for the assessment of NZVI-associated risks and future research directions. In this review, we summarize the current knowledge on the uptake, distribution, and accumulation of NZVI in plants; the phytotoxicity triggered by NZVI exposure at the physiological, biochemical, and molecular levels; and the defense mechanism used by plants to defend against NZVI-induced insults. We further discuss the toxic effects of NZVI on soil animals and microorganisms as well as the risk posed by the presence of NZVI in the food chain.


Assuntos
Recuperação e Remediação Ambiental , Nanopartículas Metálicas , Nanopartículas , Poluentes do Solo , Animais , Ecossistema , Humanos , Ferro/química , Ferro/toxicidade , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Nanopartículas/química , Solo/química , Poluentes do Solo/análise
5.
J Allergy Clin Immunol ; 147(5): 1907-1923.e6, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33045280

RESUMO

BACKGROUND: STAT3 or dedicator of cytokinesis protein 8 (Dock8) loss-of-function (LOF) mutations cause hyper-IgE syndrome. The role of abnormal T-cell function has been extensively investigated; however, the contribution of B-cell-intrinsic dysfunction to elevated IgE levels is unclear. OBJECTIVE: We sought to determine the underlying molecular mechanism of how STAT3 regulates B-cell receptor (BCR) signaling, B-cell differentiation, and IgE production. METHODS: We used samples from patients with STAT3 LOF mutation and samples from the STAT3 B-cell-specific knockout (KO) mice Mb1CreStat3flox/flox mice (B-STAT3 KO) to investigate the mechanism of hyper-IgE syndrome. RESULTS: We found that the peripheral B-cell homeostasis in B-STAT3 KO mice mimicked the phenotype of patients with STAT3 LOF mutation, having decreased levels of follicular and germinal center B cells but increased levels of marginal zone and IgE+ B cells. Furthermore, B-STAT3 KO B cells had reduced BCR signaling following antigenic stimulation owing to reduced BCR clustering and decreased accumulation of Wiskott-Aldrich syndrome protein and F-actin. Excitingly, a central hub protein, 14-3-3σ, which is essential for the increase in IgE production, was enhanced in the B cells of B-STAT3 KO mice and patients with STAT3 LOF mutation. The increase of 14-3-3σ was associated with increased expression of the upstream mediator, microRNA146A. Inhibition of 14-3-3σ with R18 peptide in B-STAT3 KO mice rescued the BCR signaling, follicular, germinal center, and IgE+ B-cell differentiation to the degree seen in wild-type mice. CONCLUSIONS: Altogether, our study has established a novel regulatory pathway of STAT3-miRNA146A-14-3-3σ to regulate BCR signaling, peripheral B-cell differentiation, and IgE production.


Assuntos
Proteínas 14-3-3/imunologia , Linfócitos B/imunologia , Imunoglobulina E/imunologia , MicroRNAs/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Fator de Transcrição STAT3/imunologia , Adolescente , Animais , Diferenciação Celular , Células Cultivadas , Criança , Pré-Escolar , Feminino , Humanos , Síndrome de Job/genética , Síndrome de Job/imunologia , Mutação com Perda de Função , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator de Transcrição STAT3/genética , Transdução de Sinais
6.
Appl Microbiol Biotechnol ; 105(16-17): 6451-6462, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34357427

RESUMO

Hydrogen sulfide (H2S), an emerging gas transmitter, has been shown to be involved in multiple intracellular physiological and biochemical processes. In this study, the effects of hydrogen sulfide coupled with calcium on cadmium removal and resistance in Phanerochaete chrysosporium were examined. The results revealed that H2S enhanced the uptake of calcium by P. chrysosporium to resist cadmium stress. The removal and accumulation of cadmium by the mycelium was reduced by H2S and Ca2+ pretreatment. Moreover, oxidative damage and membrane integrity were alleviated by H2S and Ca2+. Corresponding antioxidative enzyme activities and glutathione were also found to positively respond to H2S and Ca2+, which played an important role in the resistance to cadmium-induced oxidative stress. The effects of hydroxylamine (HA; a hydrogen sulfide inhibitor) and ethylene glycol-bis-(2-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA; a calcium chelator) toward H2S and Ca2+ and their cross-interactions confirmed the positive roles and the potential crosstalk of H2S and Ca2+ in cadmium stress resistance. These findings imply that the protective effects of H2S in P. chrysosporium under cadmium stress may occur through a reduction in the accumulation of cadmium and promotion of the antioxidant system, and the H2S-regulated pathway may be associated with the intracellular calcium signaling system.Key points• Altered monoterpenoid tolerance mainly related to altered activity of efflux pumps.• Increased tolerance to geranic acid surprisingly caused by decreased export activity.• Reduction of export activity can be beneficial for biotechnological conversions.


Assuntos
Fenômenos Bioquímicos , Sulfeto de Hidrogênio , Phanerochaete , Cádmio/toxicidade , Cálcio
7.
Cell Mol Life Sci ; 77(21): 4441-4447, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32405720

RESUMO

In the original published version of the article, the red squares in the figures which indicated the corrections.

8.
Cell Mol Life Sci ; 77(21): 4379-4395, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32016488

RESUMO

As an important chemokine receptor, the role of CX3CR1 has been studied extensively on the migration of lymphocytes including T and B cells. Although CX3CR1+ B cells have immune suppressor properties, little is known about its role on the regulation of BCR signaling and B cell differentiation as well as the underlying molecular mechanism. We have used CX3CR1 KO mice to study the effect of CX3CR1 deficiency on BCR signaling and B cell differentiation. Interestingly, we found that proximal BCR signaling, such as the activation of CD19, BTK and SHIP was reduced in CX3CR1 KO B cells upon antigenic stimulation. However, the activation of mTORC signaling was enhanced. Mechanistically, we found that the reduced BCR signaling in CX3CR1 KO B cells was due to reduced BCR clustering, which is caused by the enhanced actin accumulation by the plasma membrane via increased activation of WASP. This caused an increased differentiation of MZ B cells in CX3CR1 KO mice and an enhanced generation of plasma cells (PC) and antibodies. Our study shows that CX3CR1 regulates BCR signaling via actin remodeling and affects B cell differentiation and the humoral immune response.


Assuntos
Actinas/metabolismo , Linfócitos B/citologia , Receptor 1 de Quimiocina CX3C/metabolismo , Receptores de Antígenos de Linfócitos B/metabolismo , Animais , Linfócitos B/metabolismo , Receptor 1 de Quimiocina CX3C/genética , Diferenciação Celular , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais
9.
J Environ Sci (China) ; 100: 110-116, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33279024

RESUMO

As an aliphatic amino acid, cysteine (CYS) is diffuse in the living cells of plants and animals. However, little is known of its role in the reactivity of nano-sized zero-valent iron (NZVI) in the degradation of pollutants. This study shows that the introduction of CYS to the NZVI system can help improve the efficiency of reduction, with 30% more efficient degradation and a reaction rate constant nine times higher when nitrobenzene (NB) is used as probe compound. The rates of degradation of NB were positively correlated with the range of concentrations of CYS from 0 to 10 mmol/L. The introduction of CYS increased the maximum concentration of Fe(III) by 12 times and that of Fe(II) by four times in this system. A comparison of systems featuring only CYS or Fe(II) showed that the direct reduction of NB was not the main factor influencing its CYS-stimulated removal. The reduction in the concentration of CYS was accompanied by the generation of cystine (CY, the oxidized form of cysteine), and both eventually became stable. The introduction of CY also enhanced NB degradation due to NZVI, accompanied by the regeneration of CYS. This supports the claim that CYS can accelerate electron transfer from NZVI to NB, thus enhancing the efficiency of degradation of NB.


Assuntos
Ferro , Poluentes Químicos da Água , Cisteína , Elétrons , Nitrobenzenos , Poluentes Químicos da Água/análise
10.
Cell Commun Signal ; 18(1): 56, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32252758

RESUMO

BACKGROUND: AKT2 is one of the key molecules that involves in the insulin-induced signaling and the development of cancer. In B cells, the function of AKT2 is unclear. METHODS: In this study, we used AKT2 knockout mice model to study the role of AKT2 in BCR signaling and B cell differentiation. RESULTS: AKT2 promotes the early activation of B cells by enhancing the BCR signaling and actin remodeling. B cells from AKT2 KO mice exhibited defective spreading and BCR clustering upon stimulation in vitro. Disruption of Btk-mediated signaling caused the impaired differentiation of germinal center B cells, and the serum levels of both sepecific IgM and IgG were decreased in the immunized AKT2 KO mice. In addition, the actin remodeling was affected due to the decreased level of the activation of WASP, the actin polymerization regulator, in AKT2 KO mice as well. As a crucial regulator of both BCR signaling and actin remodeling during early activation of B cells, the phosphorylation of CD19 was decreased in the AKT2 absent B cells, while the transcription level was normal. CONCLUSIONS: AKT2 involves in the humoral responses, and promotes the BCR signaling and actin remodeling to enhance the activation of B cells via regulating CD19 phosphorylation. Video Abstract.


Assuntos
Actinas/metabolismo , Antígenos CD19/imunologia , Linfócitos B , Proteínas Proto-Oncogênicas c-akt/fisiologia , Receptores de Antígenos de Linfócitos B/imunologia , Animais , Linfócitos B/citologia , Linfócitos B/imunologia , Diferenciação Celular , Imunidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais
11.
Dermatol Surg ; 46(8): 1030-1034, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31625953

RESUMO

BACKGROUND: Bleomycin foam is an effective sclerotherapy method for venous malformations. The preparation method is rather complicated, and the volume and stability of the foam are limited. OBJECTIVE: To modify the currently used method for preparing bleomycin foam, to simplify the preparation procedure, and to produce foam with greater volume and increased stability. MATERIALS AND METHODS: Experiment 1: 6.0 IU of bleomycin powder was dissolved in different human serum albumin (HSA):saline solution (SS) ratios of 0.5:1.5, 0.75:1.25, 1:1, 1.25:0.75, 1.5:0.5, 1.75:0.25, and 2:0 in volume; then, an air:liquid ratio of 2:1 was used to create foam using the Tessari method. Experiment 2: 6.0 IU of bleomycin was dissolved directly in 2.0 mL of HSA; then, air:liquid ratios of 1:1, 2:1, 3:1, and 4:1 were used to create foam using the Tessari method. The optimum proportions of HSA:SS and air:liquid were screened by comparing the foam half-life (FHL). RESULTS: Experiment 1: the optimum proportion of HSA:SS was 2:0, and the FHL was 7.5 minutes. Experiment 2: the optimum proportion of air:liquid was 3:1, and the FHL was 9.0 minutes. CONCLUSION: The modified method is simpler and could produce more stable bleomycin foam with greater volume.


Assuntos
Bleomicina , Composição de Medicamentos/métodos , Soluções Esclerosantes , Escleroterapia , Ar , Estabilidade de Medicamentos , Meia-Vida , Albumina Sérica , Fatores de Tempo
12.
Ecotoxicol Environ Saf ; 206: 111192, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32858326

RESUMO

The phytogenic algicide sanguinarine shows strong inhibitory effects on some bloom-forming cyanobacteria and exhibits great potential in cyanobacterial bloom mitigation. To evaluate the possible ecological effects of sanguinarine on microalgae, the effects and possible mechanisms of sanguinarine on the competition between bloom-forming cyanobacterium Raphidiopsis raciborskii (formerly named Cylindrospermopsis raciborskii) and green alga Scenedesmus obliquus were investigated through co-culture competition test and comparative toxicological study including growth characteristics, chlorophyll fluorescence transients, activities of antioxidant enzymes, and lipid peroxidation. The results of Raphidiopsis-Scenedesmus co-culture competition test showed that sanguinarine decreased the competition ability of R. raciborskii, which benefitted S. obliquus in winning the competition. Toxicological studies have shown that sanguinarine exhibited high inhibitory effects on the growth and photosynthesis of R. raciborskii but no obvious toxicity on S. obliquus at concentrations of no more than 80 µg L-1. Oxidative damage partially contributed but was not the primary mechanism for the toxicity of sanguinarine on R. raciborskii. The results presented in this study indicate that sanguinarine may be a good algicidal candidate in mitigation of Raphidiopsis-based water bloom.


Assuntos
Benzofenantridinas/toxicidade , Cylindrospermopsis/efeitos dos fármacos , Herbicidas/toxicidade , Isoquinolinas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Scenedesmus/efeitos dos fármacos , Benzofenantridinas/farmacologia , Técnicas de Cocultura , Cylindrospermopsis/crescimento & desenvolvimento , Cylindrospermopsis/metabolismo , Eutrofização , Herbicidas/farmacologia , Isoquinolinas/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fotossíntese/efeitos dos fármacos , Scenedesmus/crescimento & desenvolvimento , Scenedesmus/metabolismo
13.
Ecotoxicol Environ Saf ; 203: 111054, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888616

RESUMO

Quinclorac (3,7-dichloroquinoline-8-carboxylic acid, QNC) is a highly selective auxin herbicide that is typically applied to paddy rice fields. Its residue is a serious problem in crop rotations. In this study, Oryza sativa L. seedlings was used as a model plant to explore its biochemical response to abiotic stress caused by QNC and nZVI coexposure, as well as the interactions between QNC and nZVI treatments. Exposure to 5 and 10 mg/L QNC reduced the fresh biomass by 26.6% and 33.9%, respectively, compared to the control. The presence of 50 and 250 mg/L nZVI alleviated the QNC toxicity, but the nZVI toxicity was aggravated by the coexist of QNC. Root length was enhanced upon exposure to low or medium doses of both QNC and nZVI, whereas root length was inhibited under high-dose coexposure. Both nZVI and QNC, either alone or in combination, significantly inhibited the biosynthesis of chlorophyll, and the inhibition rate increased with elevated nZVI and QNC concentration. It was indicated that nZVI or QNC can affect the plant photosynthesis, and there was a significant interaction between the two treatments. Effects of QNC on the antioxidant response of Oryza sativa L. differed in the shoots and roots; generally, the introduction of 50 and 250 mg/L nZVI alleviated the oxidative stress (POD in shoots, SOD and MDA in roots) induced by QNC. However, 750 mg/kg nZVI seriously damaged Oryza sativa L. seedlings, which likely resulted from active iron deficiency. QNC could be removed from the culture solution by nZVI; as a result, nZVI suppressed QNC uptake by 20%-30%.


Assuntos
Antioxidantes/metabolismo , Ferro/toxicidade , Nanopartículas/toxicidade , Oryza/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Quinolinas/toxicidade , Poluentes do Solo/toxicidade , Transporte Biológico , Biomassa , Clorofila/metabolismo , Relação Dose-Resposta a Droga , Interações Medicamentosas , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo
14.
Ecotoxicol Environ Saf ; 190: 109143, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31865203

RESUMO

Phthalate esters (PAEs) are one of the most frequently detected organic pollutants in soils. In this work, the adsorption behaviors of di-ethyl phthalate (DEP) and dibutyl phthalate (DBP) on soils, humins (HM) and Clay organo-mineral complexes (Clay-OM) from four regions in China, Changchun (CC), Cangzhou (CZ), Yinchuan (YC), and Changsha (CS) were studied. The surface and structural properties of these sorbents were characterized using Brunauer-Emmett-Teller specific surface area, Fourier transform infrared spectroscopy, X-ray diffraction spectroscopy, and 13C nuclear magnetic resonance methods. The results showed that the CC soil has the largest pore volume (PV) and specific surface area (SSA). PV, SSA, and aliphatic carbon content of the samples ranked as Clay-OM > HM > soil. Adsorption experiments indicated that the Clay-OM exhibited the strongest adsorption affinity for both DBP and DEP, followed by HM, and then the soil samples. Furthermore, DEP and DBP adsorption amounts on the samples declined as follows: CC > CS > CZ > YC. To illustrate the dominant mechanisms for PAEs adsorption onto soil, the soil organic carbon content normalized adsorption coefficient (LogKoc) was correlated with several possible parameters using multiple parameter linear regression and significance testing. The R2 values of the DBP and DEP in multi-regression equations were 0.825 and 0.741 respectively, and the significance test suggested that pore structure and specific surface area had crucial influences on the adsorption progress.


Assuntos
Dibutilftalato/química , Ácidos Ftálicos/química , Poluentes do Solo/química , Adsorção , Carbono/análise , China , Argila/química , Ésteres , Substâncias Húmicas , Minerais/química , Solo/química
15.
J Allergy Clin Immunol ; 144(5): 1377-1390.e4, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31405607

RESUMO

BACKGROUND: B-cell receptor (BCR) signaling, combined with CD19 and CD21 signals, imparts specific control of B-cell responses. Dedicator of cytokinesis protein 2 (DOCK2) is critical for the migration and motility of lymphocytes. Although absence of DOCK2 leads to lymphopenia, little is known about the signaling mechanisms and physiologic functions of DOCK2 in B cells. OBJECTIVE: We sought to determine the underlying molecular mechanism of how DOCK2 regulates BCR signaling and peripheral B-cell differentiation. METHODS: In this study we used genetic models for DOCK2, Wiskott-Aldrich syndrome protein (WASP), and lymphoid enhancer-binding factor 1 deficiency to study their interplay in BCR signaling and B-cell differentiation. RESULTS: We found that the absence of DOCK2 led to downregulation of proximal and distal BCR signaling molecules, including CD19, but upregulation of SH2-containing inositol 5 phosphatase 1, a negative signaling molecule. Interestingly, DOCK2 deficiency reduced CD19 and CD21 expression at the mRNA and/or protein levels and was associated with reduced numbers of marginal zone B cells. Additionally, loss of DOCK2 reduced activation of WASP and accelerated degradation of WASP, resulting into reduced actin accumulation and early activation of B cells. Mechanistically, the absence of DOCK2 upregulates the expression of lymphoid enhancer-binding factor 1. These differences were associated with altered humoral responses in the absence of DOCK2. CONCLUSIONS: Overall, our study has provided a novel underlying molecular mechanism of how DOCK2 deficiency regulates surface expression of CD21, which leads to downregulation of CD19-mediated BCR signaling and marginal zone B-cell differentiation.


Assuntos
Linfócitos B/fisiologia , Proteínas Ativadoras de GTPase/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Proteína da Síndrome de Wiskott-Aldrich/metabolismo , Síndrome de Wiskott-Aldrich/metabolismo , Animais , Antígenos CD19/genética , Antígenos CD19/metabolismo , Diferenciação Celular , Células Cultivadas , Proteínas Ativadoras de GTPase/genética , Regulação da Expressão Gênica , Fatores de Troca do Nucleotídeo Guanina/genética , Humanos , Fator 1 de Ligação ao Facilitador Linfoide/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ligação Proteica , Receptores de Antígenos de Linfócitos B/metabolismo , Receptores de Complemento 3d/genética , Receptores de Complemento 3d/metabolismo , Transdução de Sinais , Síndrome de Wiskott-Aldrich/genética , Proteína da Síndrome de Wiskott-Aldrich/genética
16.
Cell Immunol ; 337: 15-21, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30661670

RESUMO

As an atypical guanine nucleotide exchange factor (GEF), Dock5 has been extensively studied in cellular functions. However, the role of Dock5 on B-cell immunity still remain elusive. In this study, we generated a Dock5 knockout mouse model to study the effect of Dock5 deficiency on B cell development, differentiation and BCR signaling. We found that the absence of Dock5 leads to a moderate effect on B cell development in the bone marrow and reduces follicular (FO) and marginal zone (MZ) B cells. Mechanistically, the key positive upstream B-cell receptor (BCR) signaling molecules, CD19 and Brutons tyrosine kinase (Btk), whose activation determines the fate of FO and MZ B cells, is reduced in Dock5 KO B cells upon antigenic stimulation by using total internal reflection fluorscence microscopy (TIRF) and immunoblot. Interestingly we found that the cellular filamentous actin (F-actin), also decreased in Dock5 KO B cells upon stimulation, which, in turn, offers feedback to BCR signaling. Our study has unveiled that Dock5 regulates the peripheral B cell differentiation via controlling the CD19-Btk signaling axis as well as actin reorganization.


Assuntos
Linfócitos B/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Receptores de Antígenos de Linfócitos B/metabolismo , Actinas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Animais , Antígenos CD19 , Linfócitos B/imunologia , Diferenciação Celular , Fatores de Troca do Nucleotídeo Guanina/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Tirosina Quinases/metabolismo , Transdução de Sinais/imunologia
17.
J Environ Manage ; 242: 121-130, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31028952

RESUMO

Heavy metal contamination of soil has become a serious global issue because of their persistence in the environment and the non-biodegradable nature leading to their accumulation to toxic levels. In order to achieve early warning and prevent soil quality from deteriorating, it is necessary to select suitable indices to diagnose heavy metal pollution. Microbiological indices for monitoring soil pollution by heavy metals are gaining attention. However, the related researches are scattered, and critical review is imperative. This review is mainly to provide readers with an in-depth understanding of the merits and limitations of microbiological indices for heavy metals contaminated and remediated soils. Microbiological indicators include microbial abundance, community diversity and structure, functional activity. The changes of different microbiological indices and the mechanism of microbial response to heavy metal stress in soils are comprehensively summarized. Furthermore, research gaps and future directions of the microbial ecotoxicological diagnosis of soil contamination by heavy metals are also proposed and discussed.


Assuntos
Metais Pesados , Poluentes do Solo , Monitoramento Ambiental , Poluição Ambiental , Solo
18.
J Environ Sci (China) ; 75: 181-192, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30473283

RESUMO

Due to the wide use of silver nanoparticles (AgNPs) in various fields, it is crucial to explore the potential negative impacts on the aquatic environment of AgNPs entering into the environment in different ways. In this study, comparative experiments were conducted to investigate the toxicological impacts of polyvinylpyrrolidone-coated silver nanoparticles (PVP-AgNPs) with two kinds of dosing regimens, continuous and one-time pulsed dosing, in different exposure media (deionized water and XiangJiang River water). There were a number of quite different experimental results (including 100% mortality of zebrafish, decline in the activity of enzymes, and lowest number and length of adventitious roots) in the one-time pulsed dosing regimen at high PVP-AgNP concentration exposure (HOE) compared to the three other treatments. Meanwhile, we determined that the concentration of leached silver ions from PVP-AgNPs was too low to play a role in zebrafish death. Those results showed that HOE led to a range of dramatic ecosystem impacts which were more destructive than those of other treatments. Moreover, compared with the continuous dosing regimen, despite the fact that higher toxicity was observed for HOE, there was little difference in the removal of total silver from the aquatic environment for the different dosing regimens. No obvious differences in ecological impacts were observed between different water columns under low concentration exposure. Overall, this work highlighted the fact that the toxicity of AgNPs was impacted by different dosing regimens in different exposure media, which may be helpful for assessments of ecological impacts on aquatic environments.


Assuntos
Ecossistema , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Relação Dose-Resposta a Droga , Peixe-Zebra
19.
Small ; 14(32): e1800871, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29952105

RESUMO

Graphene has been employed as an excellent support for metal nanomaterials because of its unique structural and physicochemical properties. Silver nanoparticles (AgNPs) with exceptional properties have received considerable attention in various fields; however, particle aggregation limits its application. Therefore, the combination of AgNPs and graphene based nanocomposites (Ag-graphene based nanocomposites) has been widely explored to improve their properties and applications. Excitingly, enhanced antimicrobial, catalytic, and surface enhanced Raman scattering properties are obtained after their combination. In order to have a comprehensive knowledge of these nanocomposites, this Review highlights the chemical and biological synthesis of Ag-graphene nanocomposites. In particular, their applications as antimicrobial agents, catalysts, and sensors in biomedicine, agricultural protection, and environmental remediation and detection are covered. Meanwhile, the factors that influence the synthesis and applications are also briefly discussed. Furthermore, several important issues on the challenges and new directions are also provided for further development of these nanocomposites.


Assuntos
Grafite/química , Nanocompostos/química , Prata/química , Anti-Infecciosos/farmacologia , Incrustação Biológica , Catálise
20.
Dermatol Surg ; 44(11): 1421-1426, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29933299

RESUMO

BACKGROUND: Foam sclerotherapy is an effective treatment strategy for venous malformations (VMs). Stability is one of the characteristics of sclerosant foams that determine the sclerosing power. OBJECTIVE: To evaluate the clinical outcomes of sclerotherapy with prolonged half-life of hyaluronic acid (HA)-polidocanol (POL) foam for treating head and neck VMs. MATERIALS AND METHODS: Seventy patients with head and neck VMs were enrolled between October 2013 and January 2015 in Qilu Hospital Shandong University. Sclerotherapy was performed with prolonged half-life POL foam by addition of 0.05% HA. All patients were followed up at 1, 3, and 6 months. Reviews on the site and size of the lesion, times and duration of treatments, therapeutic response, and complications were performed to evaluate the end result. RESULTS: Sites of lesions included face, bucca, parotid region, neck, tongue, floor of mouth, lip, forehead, palate, and nose. An overall average of 2.5 treatments was required. Total response rate was 100%. "Resolution" was achieved in 21 cases (30%) and a significant response in 49 patients (70%). Immediate swelling was the most common complication. Epidermal extravasation was seen in 1 patient. Mucosal ulcer was observed in 1 patient. No generalized complications occurred. CONCLUSION: The prolonged half-life of HA-POL foam sclerotherapy of VMs in the head and neck is safe and effective.


Assuntos
Cabeça/irrigação sanguínea , Ácido Hialurônico/uso terapêutico , Pescoço/irrigação sanguínea , Polidocanol/uso terapêutico , Soluções Esclerosantes/uso terapêutico , Escleroterapia/métodos , Malformações Vasculares/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
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