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1.
Langmuir ; 40(24): 12573-12593, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38843172

RESUMO

Through the substitution reaction between 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and sodium lignosulfonate (LS), a novel phosphorus-containing sodium lignosulfonate (DAL) was successfully synthesized via the solvothermal method and used as a multifunctional flame retardant to prepare a novel silicone-acrylic emulsion (SAE) composite Si-P-C coating. The structure of DAL was determined by X-ray diffraction (XRD), attenuated total reflection infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and nuclear magnetic resonance (solid-state 13C NMR and 31P NMR). The results demonstrated that incorporating an appropriate dosage of DAL (0.9 g, 1.5 wt %) into SAE-based composite coatings enhances flame retardancy and reduces heat release and smoke production during burning. The peak heat release rate (p-HRR) decreases from 236.7 to 120.3 kW·m-2, total smoke production (TSP) decreases by 71.1%, and the flame-retardant index increases from 1.00 to 4.58. Meanwhile, the coating is transformed into a dense and nonflammable vitreous polyphosphate barrier layer during the firing process to prevent heat or mass transfer. Furthermore, the pyrolysis kinetics identify that the 3D Z-L-T model governs the coatings' pyrolysis, and the appropriate DAL makes the pyrolysis Eα climb from 300.98 to 331.30 kJ·mol-1 at 358-439 °C. Hence, this study presents a new synthesis method of multifunctional flame retardant DAL, studies the excellent properties and cross-linking mechanism of DAL-doped SAE-composite Si-P-C coatings, and explores a halogen-free, low-carbon, and clean eco-technology strategy.

2.
PLoS Pathog ; 12(2): e1005423, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26871705

RESUMO

Schistosomes, blood flukes, are an important global public health concern. Paired adult female schistosomes produce large numbers of eggs that are primarily responsible for the disease pathology and critical for dissemination. Consequently, understanding schistosome sexual maturation and egg production may open novel perspectives for intervening with these processes to prevent clinical symptoms and to interrupt the life-cycle of these blood-flukes. microRNAs (miRNAs) are key regulators of many biological processes including development, cell proliferation, metabolism, and signal transduction. Here, we report on the identification of Schistosoma japonicum miRNAs using small RNA deep sequencing in the key stages of male-female pairing, gametogenesis, and egg production. We identified 38 miRNAs, including 10 previously unknown miRNAs. Eighteen of the miRNAs were differentially expressed between male and female schistosomes and during different stages of sexual maturation. We identified 30 potential target genes for 16 of the S. japonicum miRNAs using antibody-based pull-down assays and bioinformatic analyses. We further validated some of these target genes using either in vitro luciferase assays or in vivo miRNA suppression experiments. Notably, suppression of the female enriched miRNAs bantam and miR-31 led to morphological alteration of ovaries in female schistosomes. These findings uncover key roles for specific miRNAs in schistosome sexual maturation and egg production.


Assuntos
MicroRNAs/genética , Ovário/crescimento & desenvolvimento , Ovário/patologia , Schistosoma japonicum/genética , Esquistossomose/genética , Animais , Sequência de Bases , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Masculino , Camundongos Endogâmicos BALB C , Coelhos , Análise de Sequência de RNA/métodos , Diferenciação Sexual
3.
Parasitol Res ; 113(11): 4261-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25185668

RESUMO

Schistosomiasis is a worldwide parasitic disease, and while it can be successfully treated with chemotherapy, this does not prevent reinfection with the parasite. Adenovirus vectors have been widely used for vaccine delivery, and a vaccination approach has the potential to prevent infection with Schistosoma. Here, we developed a recombinant adenoviral vector that expresses Schistosoma japonicum inhibitor apoptosis protein (Ad-SjIAP) and assessed its immunoprotective functions against schistosomiasis in mice. Murine immune responses following vaccination were investigated using enzyme-linked immunosorbent assays (ELISA), lymphocyte proliferation, and cytokine assays. The protective immunity in mice was evaluated by challenging with S. japonicum cercariae. Our results indicated that immunization with the Ad-SjIAP in mice induced a strong serum IgG response against IAP including IgG1, IgG2a, and IgG2b. In addition, lymphocyte proliferation experiments showed that mice treated with Ad-SjIAP significantly increased the lymphocyte response upon stimulation with recombinant Schistosoma japonicum inhibitor apoptosis protein (rSjIAP). Moreover, cytokine assays indicated that vaccination of Ad-SjIAP significantly increased the production of interferon (IFN)-γ and IL-2 as compared to the corresponding control group. Furthermore, following the challenge with S. japonicum cercariae, the vaccine conferred moderate protection, with an average rate of 37.95% for worm reduction and 31.7% for egg reduction. Taken together, our preliminarily results suggested that schistosoma IAP may be a potential vaccine against S. japonicum and that adenoviral vectors may serve as an alternative delivery vehicle for schistosome vaccine development.


Assuntos
Proteínas de Helminto/imunologia , Proteínas Inibidoras de Apoptose/imunologia , Esquistossomose Japônica/imunologia , Vacinas Sintéticas/imunologia , Adenoviridae , Animais , Anticorpos Anti-Helmínticos/sangue , Ensaio de Imunoadsorção Enzimática , Imunoglobulina G/sangue , Interferon gama/imunologia , Interleucina-2/imunologia , Ativação Linfocitária/imunologia , Camundongos Endogâmicos BALB C , Contagem de Ovos de Parasitas , Schistosoma japonicum , Baço/citologia , Baço/imunologia
4.
Parasitol Res ; 111(6): 2317-24, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22932940

RESUMO

Cytokine-induced apoptosis inhibitor (CIAP) is a novel antiapoptotic molecule, which is different to inhibitor of apoptosis protein or B-cell lymphoma 2. CIAP was originally identified as a molecule that conferred resistance to apoptosis induced by growth factor starvation. However, it remains to be undercharacterized in schistosomes. Here, we molecularly characterize a novel cytokine-induced apoptosis inhibitor from Schistosoma japonicum (SjCIAP). The transcription of the SjCIAP occurred at all of developmental stages investigated including eggs, cercariae, schistosomula, and adult schistosomes. Functional assay indicated that the SjCIAP could inhibit caspase activity in either human cell lines or schistosome lysates. Our preliminary results suggest that the SjCIAP may play important roles in parasitic living and development by regulating apoptosis, and drug target of SjCIAP might be a potential for schistosomiasis control.


Assuntos
Proteínas Reguladoras de Apoptose/biossíntese , Proteínas Reguladoras de Apoptose/genética , Apoptose , Citocinas/metabolismo , Proteínas de Helminto/biossíntese , Proteínas de Helminto/genética , Schistosoma japonicum/efeitos dos fármacos , Animais , Caspases/metabolismo , Linhagem Celular , Perfilação da Expressão Gênica , Humanos
5.
Heliyon ; 6(3): e03457, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32154415

RESUMO

The effect of particle size on the combustion and explosion properties of grain dust is investigated by Hartmann tube, cone calorimeter (CC), and thermogravimetry (TG), it aims to provide fundamental experimental data of grain dust for an in-depth study on its potential risk. The fine-grain dust facilitates the decrease in the minimum ignition temperature (MIT) of dust layer and dust cloud, as well as the obvious increases in the maximum explosion pressure P max (climbs from 0.36 to 0.49 MPa) and pressure rising rate dP/dt (rises from 6.05 to 12.12 MPa s-1), leading to the increases in maximum combustion rate (dw/dτ)max and combustion characteristic index S, corresponding to the greater or severer potential risk. Because the E corresponding to combustion increases from 106.05 (sample with a particle size of 180-1250 µm) to 153.45 kJ mol-1 for the sample of 80-96 µm, the combustion process gradually transforms from diffusion-controlled into a kinetically controlled mode with the decreasing particle size of grain dust, together with the retardation of initially transient charring. It determines that the competition between the charring and combustion dominates the decomposition, and the combustion prevails for the coarse particle, while the charring controls the combustion for the fine-grain dust.

6.
Dev Neurobiol ; 70(11): 737-50, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20518018

RESUMO

At the onset of a period of intense synaptic refinement initiated by synchronized eye opening (EO), rapid changes in postsynaptic NMDA receptor and AMPA receptor currents (NMDARcs and AMPARcs) occur within the superficial visual layers of the rodent superior colliculus (sSC; Lu and Constantine-Paton [2004]: Neuron 43:237-249). Subsequently, evoked non-NMDARc amplitudes increase, but by 2 weeks after EO (AEO) they decrease significantly. Here, using whole-cell patch-clamp recording, we demonstrate that small, slowly desensitizing excitatory kainate receptor currents (KARcs) are responsible for the rise and subsequent fall in non-NMDARcs. The increase in KAR transmission parallels inhibitory GABA(A) responses that plateau at 7 days AEO. By 2 weeks AEO, KARcs are gone. AMPARcs remain unchanged during the appearance and disappearance of the KARcs, despite increases in sSC neuropil activity and continued refinement of inputs to individual sSC neurons. We suggest that in the interval of heightened activity, before SC inhibition matures, many AMPARcs desensitize and are relatively ineffective at relieving the Mg(2+) block on NMDARs. This transient appearance of slowly desensitizing, long-duration KARcs may provide increased membrane depolarization necessary for NMDAR function and continuation of synaptic refinement.


Assuntos
Receptores de Ácido Caínico/metabolismo , Colículos Superiores/crescimento & desenvolvimento , Colículos Superiores/metabolismo , Sinapses/fisiologia , Animais , Potenciais da Membrana/fisiologia , Neurônios/metabolismo , Técnicas de Patch-Clamp , Ratos , Ratos Sprague-Dawley , Receptores de AMPA/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Regulação para Cima
7.
Nan Fang Yi Ke Da Xue Xue Bao ; 26(7): 1017-9, 2006 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16864102

RESUMO

OBJECTIVE: To study the effect of exercises of different intensities on rat skeletal muscle cell apoptosis. METHODS: Rat models of exhaustive exercise-induced skeletal muscle injury was established using tread mill exercises at different speeds, and the skeletal muscle cell apoptosis was detected using propidium iodide (PI) staining and flow cytometry. RESULT: No obvious gastrocnemius cell apoptosis was observed in rats with normal exercise (P>0.05), but the cell apoptosis index was statistically significant in moderate and exhaustive exercise groups (P<0.05), reaching the highest level in exhaustive exercise group after exercising. The gastrocnemius cell apoptosis index increased obviously on days 1 and 3 of exercise, and stabilized in moderate and exhaustive exercise groups. CONCLUSION: Exercises can evoke cell apoptosis and accelerate apoptotic cell clearance, and the imbalance between the two events during exercises may contribute to skeletal muscle injury.


Assuntos
Apoptose/fisiologia , Músculo Esquelético/fisiopatologia , Condicionamento Físico Animal/fisiologia , Animais , Citometria de Fluxo , Masculino , Músculo Esquelético/citologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
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