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1.
Toxics ; 12(5)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38787149

RESUMO

Nanoplastics, created by the fragmentation of larger plastic debris, are a serious pollutant posing substantial environmental and health risks. Here, we developed a polystyrene nanoparticle (PS-NP) exposure model during mice pregnancy to explore their effects on embryonic development. We found that exposure to 30 nm PS-NPs during pregnancy resulted in reduced mice placental weight and abnormal embryonic development. Subsequently, our transcriptomic dissection unveiled differential expression in 102 genes under PS-NP exposure and the p38 MAPK pathway emerged as being significantly altered in KEGG pathway mapping. Our findings also included a reduction in the thickness of the trophoblastic layer in the placenta, diminished cell invasion capabilities, and an over-abundance of immature red cells in the blood vessels of the mice. In addition, we validated our findings through the human trophoblastic cell line, HTR-8/SVneo (HTR). PS-NPs induced a drop in the vitality and migration capacities of HTR cells and suppressed the p38 MAPK signaling pathway. This research highlights the embryotoxic effects of nanoplastics on mice, while the verification results from the HTR cells suggest that there could also be certain impacts on the human trophoblast layer, indicating a need for further exploration in this area.

2.
J Environ Sci (China) ; 71: 150-167, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30195674

RESUMO

Continuous observation of isoprene, α-pinene and ß-pinene was carried out in a typical urban area of Beijing from March 2014 to February 2015, using an AirmoVOC online analyzer. Based on the analysis of the ambient level and variation characteristics of isoprene, α-pinene and ß-pinene, the chemical reactivity was studied, and their sources were identified. Results showed that the concentrations of isoprene, α-pinene and ß-pinene in the urban area of Beijing were lower than those in richly vegetated areas; the concentrations of isoprene were at a moderate level compared with those of previous studies of Beijing. Concentrations of isoprene, α-pinene and ß-pinene showed different seasonal, monthly, daily and diurnal variations, and all of the three species showed higher level at night than those in the daytime as a whole, the variations of isoprene, α-pinene and ß-pinene mainly influenced by emission of sources, photochemical reaction, and meteorological parameters. Isoprene was the largest contributor to the total OFP values than α-pinene and ß-pinene. α-Pinene was the largest contributor to the total SOAFP values than isoprene and ß-pinene in autumn, while isoprene was the largest one in other seasons. Isoprene, α-pinene and ß-pinene were derived mainly from biological sources; and α-pinene level were also affected by industrial sources. To reduce the concentrations of isoprene, α-pinene and ß-pinene, it is necessary to scientifically select urban green plant species, and more strict control measures should be taken to reduce the emission of α-pinene from industrial sources, such as artificial flavors and resins synthesis processes.


Assuntos
Poluentes Atmosféricos/análise , Butadienos/análise , Monitoramento Ambiental , Hemiterpenos/análise , Pentanos/análise , Poluição do Ar/estatística & dados numéricos , Atmosfera/química , Pequim
3.
Opt Express ; 23(16): 20655-67, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26367918

RESUMO

The general structure of a free-space optical (FSO) communication system based on astronomical telescopes is proposed. The light path for astronomical observation and for communication can be easily switched. A separate camera is used as a star sensor to determine the pointing direction of the optical terminal's antenna. The new system exhibits rapid acquisition and is widely applicable in various astronomical telescope systems and wavelengths. We present a detailed analysis of the acquisition time, which can be decreased by one order of magnitude compared with traditional optical communication systems. Furthermore, we verify software algorithms and tracking accuracy.

4.
Opt Express ; 21(15): 18434-41, 2013 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-23938715

RESUMO

We propose a novel fiber-based free-space optical (FSO) coherent receiver for inter-satellite communication. The receiver takes advantage of established fiber-optic components and utilizes the fine-pointing subsystem installed in FSO terminals to minimize the influence of satellite platform vibrations. The received beam is coupled to a single-mode fiber, and the coupling efficiency of the system is investigated both analytically and experimentally. A receiving sensitivity of -38 dBm is obtained at the forward error correction limit with a transmission rate of 22.4 Gbit/s. The proposed receiver is shown to be a promising component for inter-satellite optical communication.


Assuntos
Artefatos , Tecnologia de Fibra Óptica/instrumentação , Modelos Teóricos , Astronave/instrumentação , Telecomunicações/instrumentação , Simulação por Computador , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Retroalimentação , Luz , Espalhamento de Radiação
5.
Chem Biol Interact ; 181(3): 316-21, 2009 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-19589337

RESUMO

Zn(II)-curcumin, a mononuclear (1:1) zinc complex of curcumin was synthesized and examined for its antiulcer activities against pylorus-ligature-induced gastric ulcer in rats. The structure of Zn(II)-curcumin was identified by elemental analysis, NMR and TG-DTA analysis. It was found that a zinc atom was coordinated through the keto-enol group of curcumin along with one acetate group and one water molecule. Zn(II)-curcumin (12, 24 and 48 mg/kg) dose-dependently blocked gastric lesions, significantly reduced gastric volume, free acidity, total acidity and pepsin, compared with control group (P<0.001) and curcumin alone (24 mg/kg, P<0.05). Reverse transcriptase polymerase chain reaction (RT-PCR) analysis showed that Zn(II)-curcumin markedly inhibited the induction of nuclear factor-kappa B (NF-kappaB), transforming growth factor beta(1) (TGF-beta(1)) and interleukin-8 (IL-8), compared with control group (P<0.05). These findings suggested that Zn(II)-curcumin prevented pylorus-ligation-induced lesions in rat by inhibiting NF-kappaB activation and the subsequent production of proinflammatory cytokines, indicating a synergistic effect between curcumin and zinc. An acute toxicity study showed that mice treated with SDs of Zn(II)-curcumin (2 g/kg) manifested no abnormal signs.


Assuntos
Antiulcerosos/uso terapêutico , Curcumina/análogos & derivados , Compostos Organometálicos/uso terapêutico , Úlcera Gástrica/prevenção & controle , Animais , Sequência de Bases , Curcumina/uso terapêutico , Primers do DNA , Relação Dose-Resposta a Droga , Interleucina-8/antagonistas & inibidores , Interleucina-8/biossíntese , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , NF-kappa B/antagonistas & inibidores , NF-kappa B/biossíntese , Antro Pilórico , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Crescimento Transformador beta/antagonistas & inibidores , Fator de Crescimento Transformador beta/biossíntese
6.
Int J Pharm ; 337(1-2): 25-30, 2007 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-17482394

RESUMO

A sensitive analytical method for the determination of a new active steroid, butane acid-(5-androsten-17-one-3beta-ol)-diester (A1998), was developed by high performance liquid chromatography with laser-induced fluorescence detection following the pre-column derivatization with dansylhydrazine. The calibration curve for A1998 derivatization was found linear in the dynamic range from 0.025 to 5.0 microg/ml, with the precision less than 6% (CV) and the mean extraction efficiency greater than 92%. In 200 microl of plasma samples the limit of quantitation was as low as 0.025 microg/ml with a signal-to-noise ratio of 10. This assaying was further applied to the determination of the pharmacokinetic parameters of A1998 in rats with an intravenous injection of A1998. Values for clearance for elimination, volume of distribution at steady state and terminal half life in the above case were determined as 50.3+/-1.1 ml/min kg, 1329.0+/-111.0 ml/kg and 44.0+/-2.7 min, respectively.


Assuntos
Antiarrítmicos/sangue , Cromatografia Líquida de Alta Pressão , Desidroepiandrosterona/sangue , Avaliação Pré-Clínica de Medicamentos/métodos , Lasers , Espectrometria de Fluorescência , Animais , Antiarrítmicos/administração & dosagem , Antiarrítmicos/química , Antiarrítmicos/farmacocinética , Disponibilidade Biológica , Calibragem , Catálise , Compostos de Dansil/química , Desidroepiandrosterona/administração & dosagem , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/química , Desidroepiandrosterona/farmacocinética , Avaliação Pré-Clínica de Medicamentos/normas , Feminino , Corantes Fluorescentes/química , Meia-Vida , Hidrazinas/química , Injeções Intravenosas , Taxa de Depuração Metabólica , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Temperatura , Fatores de Tempo , Ácido Trifluoracético/química
7.
World J Gastroenterol ; 11(12): 1764-8, 2005 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-15793860

RESUMO

AIM: To investigate the pharmacological effects of rice flavone (5,4'-dihydroxy-3',5'-dimethoxy-7-O-beta-D-glucopyranosyloxy-flavone, RF) separated from panicle-differentiating to flowing rice on rat experimental hepatic injury. METHODS: Models of rat acute hepatic injury induced by carbon tetrachloride (CCl(4)) administration, rat hepatic fibrosis induced by thioacetamide, injury of primary cultured rat hepatocytes induced by CCl(4), respectively, were established. After treated with RF, content of serum alanine transaminase (ALT), aspartate aminotransferase (AST) and albumin (Alb), hyaluronic acid (HA), the activity of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and hydroxyproline (Hyp) were measured and liver tissue was observed pathologically by hematoxylin-eosin (HE) staining. Effects of RF on pathological changes, function index, enzyme of scavenging free radicals and blood rheology were evaluated. RESULTS: In model of rat acute hepatic injury induced by CCl(4), RF can significantly decrease the contents of serum ALT, AST, increase the content of Alb, improve the dropsy and fat denaturalization of hepatocytes. In model of rat hepatic fibrosis induced by thioacetamide, RF can inhibit the increase of HA, Hyp and whole blood viscosity, and improve the activities of GSH-Px and SOD, and inauricular microcirculation. CONCLUSION: RF has apparent protective effects on hepatic injury by increasing activity of GSH-Px and SOD, scavenging free radicals produced by CCl(4), reducing blood viscosity, and improving microcirculation and blood supply.


Assuntos
Flavonas/farmacologia , Cirrose Hepática/tratamento farmacológico , Oryza/química , Fitoterapia , Extratos Vegetais/farmacologia , Doença Aguda , Animais , Tetracloreto de Carbono , Células Cultivadas , Modelos Animais de Doenças , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Tioacetamida
8.
Zhongguo Zhong Yao Za Zhi ; 30(3): 211-5, 2005 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-15719643

RESUMO

OBJECTIVE: To study the protective effects of polysaccharide of Spirulina platensis and Sargassum thunbeergii on vascular of alloxan (ALX) induced diabetic rats. METHOD: With the doses of polysaccharide of Spirulina platensis (PSP) and Sargassum thunbeergii (PST) compound (1:1) 12.261, 36.783, 110.349 mg x kg(-1) by i.g. administration to alloxan induced diabetic rats respectively for 6 weeks. Then the blood glucose and the TC, HDL-C, TG, NO, ET in serum were detected. The contraction and relaxation response to NE and ACh in aortic rings of the alloxan induced diabetic rats has been studied. RESULT: The results showed the compound of PSP and PST could decrease the blood glucose and the TC, TG, NO, ET in serum and increase HDL-C than in the alloxan induced diabetic rats. The contraction responses to NE in aortic rings of the alloxan induced diabetic rats were significantly elevated in the normal rats, and the responses to ACh were significantly lower. PSP and PST compound could significantly lower the responses to NE and significantly elevate the responses to ACh in aortic rings of the alloxan induced diabetic rats. CONCLUSION: PSP and PST compound could decrease blood glucose and could protect the vascular of alloxan induced diabetic rats.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Experimental/sangue , Contração Muscular/efeitos dos fármacos , Polissacarídeos Bacterianos/farmacologia , Polissacarídeos/farmacologia , Animais , Aorta Torácica/efeitos dos fármacos , Colesterol/sangue , HDL-Colesterol/sangue , Cianobactérias/química , Endotelinas/sangue , Feminino , Masculino , Camundongos , Músculo Liso Vascular/efeitos dos fármacos , Óxido Nítrico/sangue , Polissacarídeos/isolamento & purificação , Polissacarídeos Bacterianos/isolamento & purificação , Substâncias Protetoras/farmacologia , Ratos , Ratos Sprague-Dawley , Sargassum/química , Triglicerídeos/sangue
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