Neuroprotective potential of cerium oxide nanoparticles for focal cerebral ischemic stroke / 华中科技大学学报（医学）（英德文版）

During the previous years, with the emerging of nanotechnology, the enormous capabilities of nanoparticles have drawn great attention from researchers in terms of their potentials in various aspects of pharmacology. Cerium oxide nanoparticles (nanoceria), considered as one of the most widely used nanomaterials, due to its tempting catalytic antioxidant properties, show a promising potential in diverse disorders, such as cerebral ischemic stroke (CIS), cancer, neurodegenerative and inflammatory diseases. Overwhelming generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS) during cerebral ischemia and reperfusion periods is known to aggravate brain damage via sophisticated cellular and molecular mechanisms, and therefore exploration of the antioxidant capacities of nanoceria becomes a new approach in reducing cerebral ischemic injury. Furthermore, utilizing nanoceria as a drug carrier might display the propensity to overcome limitations or inefficacy of other conceivable neuroprotectants and exhibit synergistic effects. In this review, we emphasize on the principle features of nanoceria and current researches concerning nanoceria as a potential therapeutic agent or carrier in improving the prognosis of CIS.

Exposure to Cerium Oxide Nanoparticles Is Associated With Activation of Mitogen-activated Protein Kinases Signaling and Apoptosis in Rat Lungs / 예방의학회지

OBJECTIVES: With recent advances in nanoparticle manufacturing and applications, potential exposure to nanoparticles in various settings is becoming increasing likely. No investigation has yet been performed to assess whether respiratory tract exposure to cerium oxide (CeO2) nanoparticles is associated with alterations in protein signaling, inflammation, and apoptosis in rat lungs. METHODS: Specific-pathogen-free male Sprague-Dawley rats were instilled with either vehicle (saline) or CeO2 nanoparticles at a dosage of 7.0 mg/kg and euthanized 1, 3, 14, 28, 56, or 90 days after exposure. Lung tissues were collected and evaluated for the expression of proteins associated with inflammation and cellular apoptosis. RESULTS: No change in lung weight was detected over the course of the study; however, cerium accumulation in the lungs, gross histological changes, an increased Bax to Bcl-2 ratio, elevated cleaved caspase-3 protein levels, increased phosphorylation of p38 MAPK, and diminished phosphorylation of ERK-1/2-MAPK were detected after CeO2 instillation (p<0.05). CONCLUSIONS: Taken together, these data suggest that high-dose respiratory exposure to CeO2 nanoparticles is associated with lung inflammation, the activation of signaling protein kinases, and cellular apoptosis, which may be indicative of a long-term localized inflammatory response.

Efeito do cério na qualidade fisiológica de sementes de milho e no desempenho agronômico das plantas / Effect cerium on the physiological quality maize seed and agronomic performance of plants

Os elementos químicos terras raras, tais como Cério (Ce), podem ser utilizados como fertilizantes no manejo químico das culturas, visando a otimização no fornecimento de nutrientes às plantas, quando se buscam incrementos na produtividade agrícola. O objetivo do trabalho foi avaliar a qualidade fisiológica e o desempenho agronômico da cultura do milho, após tratamento das sementes com Ce. As sementes da cultivar Pioneer 30F53, foram imersas em solução aquosa, nas concentrações de 0, 5, 10, 15, 20 e 25 mg de Ce L-1, por uma hora. Após a imersão, foram realizados os testes de germinação, primeira contagem da germinação, classificação do vigor, comprimento e massa seca de plântulas, em laboratório. Em campo, sementes tratadas com a concentração de 12 mg de Ce L-1, escolhida após a primeira etapa de testes de laboratório, foram semeadas e durante o ciclo da cultura foram avaliados além do rendimento, número de dias até emergência de 50 % das plantas, número de folhas, diâmetro do colmo, estatura de plantas e número de dias até 50 % do florescimento. Concluiu-se que a aplicação de Ce em sementes de milho aumenta a germinação e o vigor das sementes, mas não influencia o crescimento vegetativo e reprodutivo. O tratamento com Ce pode induzir ao aumento do rendimento da cultura do milho.

The search for alternatives that provide increases in crop yields in agricultural systems is still present today. Chemical elements rare earths such as cerium (Ce) represent alternatives in the search for increases in agricultural productivity and has been used in several countries and many cultures. The objective of this study was to evaluate the physiological quality and agronomic performance of corn after seed treatment with Ce. Corn seeds Pioneer 30F53, since they were immersed in aqueous solution at concentrations of 0, 5, 10, 15, 20 and 25 mg L-1 Ce, for one hour. After the immersion, were performed tests of germination, first count germination, vigor classification, length and seedling dry weight in the laboratory. In the field, the seeds treated with a concentration of 12 mg L-1 Ce, previously chosen by laboratory tests were sown and during the course of the culture were measured as well as yield, number of days until emergence of the plants 50%, number leaf, stem diameter, plant height and number of days until 50% flowering. It was concluded that the application of Ce increases in corn seed germination and seed vigor, but no effect on the vegetative and reproductive growth. The treatment with Ce can induce an increase of the yield of corn.

Effects of selected metal oxide nanoparticles on multiple biomarkers in Carassius auratus / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To study the biological effects of nanoscale copper oxide (nCuO), zinc oxide (nZnO), cerium dioxide (nCeO2) and their mixtures on Carassius auratus.</p><p><b>METHODS</b>Juvenile fish (Carassius auratus) were exposed to aqueous suspensions of nCuO, nZnO, and nCeO2 (alone and in mixtures) at concentrations of 20, 40, 80, 160, and 320 mg/L. The biomarkers-acetylcholinesterase (AChE) in brain, sodium/potassium-activated ATPase (Na+/K+-ATPase) in gill, and superoxide dismutase (SOD) and catalase (CAT) in liver-were determined after 4 days of exposure. Integrated biomarker response (IBR) was calculated by combining multiple biomarkers into a single value.</p><p><b>RESULTS</b>AChE and SOD activities were significantly inhibited by all test metal oxide nanoparticles (NPs) at high concentrations (⋝160 mg/L) with the exception of nCeO2. Na+/K+-ATPase induction exhibited bell-shaped concentration-response curves. CAT activity was significantly inhibited at concentrations equal to or higher than 160 mg/L. The order of IBR values was nCeO2 ≈ nZnO/nCeO2 ≈ nCuO/nCeO2 < nCuO/nZnO/nCeO2 < nZnO < nCuO < nCuO/nZnO. The joint effect seemed to be synergistic for nCuO/nZnO mixtures, additive for the ternary mixture and less than additive or antagonistic for the binary mixtures containing nCeO2.</p><p><b>CONCLUSION</b>Concentration-dependent changes of enzymatic activities (AChE, Na+/K+-ATPase, SOD, and CAT) were observed in fish exposed to nanoscale metal oxides. IBR analysis allowed good discrimination between the different exposures and might be a useful tool for the quantification of integrated negative effects induced by NPs toward fish.</p>

Spectrophotometric and spectrofluorimetric determination of 1,4-dihydropyridine drugs using potassium permanganate and cerium [IV] ammonium sulphate

Simple and sensitive spectrophotometric and spectrofluorimetric methods have been developed for determination of 1, 4-dihydropyridine [1, 4-DHP] drugs based on the oxidation of the investigated 1, 4-DHP drugs with acidic KMnO4 [method I] or Ce [IV] [method II]. The first method is based on the decrease in the colour of the permanganate solution due to the presence of the studied drug was measured at 525 nm. And the second method is based on monitoring the fluorescence of the produced cerium [III] at emission 355 nm [excitation at 255 nm]. All variables that affect the performance of the proposed methods were carefully studied and optimized. The analytical performance of the methods was validated according to International Conference of Harmonization guidelines. The proposed methods were applied successfully to the determination of the drugs in commercial tablets and capsules. The results of the proposed procedures were statistically and compared with those obtained by the reference methods

Moxifloxacin Ameliorates Oleic Acid-induced Acute Lung Injury by Modulation of Neutrophilic Oxidative Stress in Rats / 결핵및호흡기질환

BACKGROUND: Based on the known immunoregulatory functions of moxifloxacin on phagocytes, the therapeutic effect of moxifloxacin on oleic acid (OA)-induced acute lung injury (ALI) was investigated. METHODS: Moxifloxacin (10 mg/kg) was given to male Sprague-Dawley rats that had been given oleic acid (OA, 30 microliter) intravenously. Five hours after OA injection, parameters demonstrating ALI were assessed to measure the effects of moxifloxacin on acute lung injury. RESULTS: The pathological findings of OA-induced ALI's was diminished by moxifloxacin. Through ultrastructural and CeCl3 EM histochemistry, moxifloxacin was confirmed to be effective in decreasing oxidative stress in the lung as well. Indices of ALI, such as lung weight/body weight ratio, protein content in bronchoalveolar lavage fluid, and lung myeloperoxidase were decreased by moxifloxacin. In diaminobenzidine immunohistochemistry, fluorescent immunohistochemistry, and Western blotting of the lung, moxifloxacin had decreased the enhanced expression of secretory phospholipase A2 (sPLA2) by OA. CONCLUSION: We concluded that moxifloxacin was effective in lessening acute inflammatory pulmonary edema caused by OA, by inhibiting the neutrophilic respiratory burst, which was initiated by the activation of sPLA2.

Effects of doping with CeO[2] and calcination temperature on physicohcemical properties of NiO/Al[2]O[3] system

The effects of doping with CeO[2] and calcinations temperature on physicochemical properties of NiO/Al[2]O[3] system have been investigated using DTA, XRD, nitrogen adsorption measurements at - 196 [degree sign] C techniques and decomposition of H[2]O[2] at 30-50 [degree sign] C. The pure and variously doped mixed solids were subjected to heat treatment at 300, 400, 700, 900 and 1000 [degree sign] C. The amounts of dopant were 0.75, 1.5 and 3 mol% CeO[2]. The results revealed that the presence of NiO with aluminium oxide much enhanced the degree of crystallinity of the gamma-Al[2]O[3] phase. In contrast, the presence of Al[2]O[3] much retarded the crystallization process of the NiO phase. The specific surface areas were found to increase with increasing calcinations temperature from 300 to 400 [degree sign] C and with doping of the system under investigation with CeO[2]. The pure and variously doped solids, calcined at 300 and 400 [degree sign] C, were constituted of amorphous NiO dispersed in gamma-Al[2]O[3] Heating at 700[degree sign] C resulted in formation of poorly crystalline NiO and gamma-Al[2]O[3] phases beside CeO[2] for the doped solids. Crystalline NiAl[2]O[4] phase was formed starting from 900[degree sign] C as a result of solid-solid interaction between the reacted oxides. The degree of crystallinity of NiAl[2]O[4] increased with increasing the calcinations temperature from 900 to 1000 [degree sign]. An opposite effect was observed upon doping with CeO[2]. NiO/Al[2]O[3] system calcined at 300 and 400 [degree sign] has catalytic activity higher than individual NiO obtained at the same calcinations temperature. The catalytic activity of NiO/Al[2]O[3] system increased, progressively, with increasing the amount of CeO[2] dopant. The doping process did not modify the mechanism of the catalyzed reaction but changed the concentration of active sties without changing their energetic nature

Spectrophotometric determination of certain drugs using ammonium cerium [IV] sulfate and p-dimethylaminobenzaldehyde

A spectrophotometric method for the determination of acetylcysteine, captopril carbimazole propylthiouracel and thiopental sodium is described. The method was based on the oxidation of the studied drugs with excess ammonium cerium [IV] sulfate. Followed by measuring the excess unreacted ammonium cerium [IV] sulfate, through reaction with p-DMAB into the corresponding p-dimethylaminobenzoquinone, which has a red colour can be measured at 464 nm. The decrease in the absorption intensity at 464 nm caused by the presence of the investigated drugs is directly proportional to their concentration. Investigations were carried out to study all variables and a validation study for the proposed procedure according to USP 2002 was also performed. Beer's law was obeyed in the range of 1-40 micro.g/ml. The detection limit ranged from 0.22-1.22 micro g/ml, while the quantitation limit ranged from 0.73-4.06 micro g/ml. The proposed method was successfully applied for the analysis of the studied drugs in pharmaceutical preparations with good recoveries in the range of 98.12-100.02%. Results were compared with those obtained from the pharmacopoeial or reported methods

Synthesis, structure characterization and anti-tumor activity of lanthanide complex Ln (Phen)2 (5-Fu)3 (NO3) (NO3 )2 / 药学学报

<p><b>AIM</b>To study the biochemistry of lanthanides, the cooperative action of inorganic and organic anti-tumor drugs.</p><p><b>METHODS</b>A series of rare earth complexes were synthesized with Ln(NO3) 6H2O, Phen and 5-Fu. Their anti-tumor activity was measured by the improved MTT, SRB methods.</p><p><b>RESULTS</b>The formula of complex Ln[(Phen)2(5-Fu)3(NO3)](NO3)2(Ln = Y, La, Ce, Sm, Gd, Dy, Er; Phen = 1, 10-phenanthroline; 5-Fu = fluorouracil) was characterized by elemental analyses, molar conductivity, IR, TGA, and 13C NMR spectra. The preliminary biological activity studies indicated that Lanthanide complex has strong anti-tumor activity in vitro.</p><p><b>CONCLUSION</b>The complex might have anti-tumor cooperation action.</p>

Effectiveness of ethylene glycol bis (2-aminoethyl ether) tetraacetic acid (EGTA) against cerium toxicity.

Therapeutic efficacy of EGTA (ethylene glycol bis (2-aminoethyl ether) tetraacetic acid) against cerium intoxicated mice was studied. Administration of cerium showed significant decrease in haemoglobin percentage, RBC counts and blood glucose level with an increase in the activity of serum transaminases and WBC counts. Decrease in the activity of alkaline phosphatase and glycogen content was noted in liver and kidney after cerium exposure. Light and electron microscopical investigations showed that these changes were recouped considerably with the administration of EGTA suggesting its therapeutic efficacy against cerium toxicity.

Study on the effect of Y2O3 addition to the fluorescent property of dental porcelain

The appearance of dental porcelains is comparable to natural teeth. This study discusses the effect of Y2O3 addition to the fluorescent property of dental porcelains. The composition of dental porcelains contained Y2O3 as the fluorescent agent and base frit. The combinations of Y2O3 added consist of a series with 0.5, 1.0, 1.5, 2.0 and 2.5 wt% respectively, based on the total composition. In the extreme condition, fluorescent agents are added from 5.0 up to 10.0 wt%. In order to enhance the fluorescent property of dental porcelains, an opacifiying agent, cerium oxide (CeO2) was also added to dental porcelains composition. The fluorescent property was determined using Spectroline EF-1400C/F that emits 240 nm wavelength ultraviolet light. The microstructure was examined by Scanning Electron Microscope (SEM). The result shows that, the fluorescent properties displayed are similar to natural teeth when subjected to ultraviolet light. SEM micrograph was able to show the fluorescent agent dispersed in glass phase. Increasing additions of Y2O3 gave the fluorescent properties near to natural teeth.

The influence of Ce on microstructures and mechanics performances of Ti-Fe-Mo-Mn-Nb-Zr alloys / 生物医学工程学杂志

The influences of Ce on the microstructure and mechanics performances of Ti-Fe-Mo-Mn-Nb-Zr alloys were studied and presented in this paper. The microstructure of no-Ce Ti-Fe-Mo-Mn-Nb-Zr alloy was thick, long and dendritic, and the microstructure of alloy was fined by Ce. With the increase in Ce wt%, the microstructure became equiaxial gradually. Hardness decreased with the increase in Ce wt%. The compression yield strength became greater with the increasing of Ce wt%, but after the Ce wt% increased to a certian degree, the compression yield strength became smaller with the further increasing of Ce wt%. This phenomenon was explained in the light of bond energy and X-ray diffraction experiment. X-ray diffraction experiment showed that the alloys were beta-Ti.

Hydrogen Peroxide Modulates Phospholipase A2 Aactivity and Endogenous Oxidative Stress in the Free Radical Induced Acute Lung Injury / 대한흉부외과학회지

BACKGROUND: In an attempt to investigate the role of oxidants in the activation of phospholipase A2(PLA2) and endogenous oxidative stress in the lung, acute inflammatory lung injury was induced by the instillation of hydrogen peroxide into the trachea of Sprague-Dawley rats. MATERIAL AND METHOD: To prove the hypothesis that released oxidants from neutrophils activate the PLA2 retrogradely, activities of PLA2 and lysoplatelet activating factor acetyltransferase(lysoPAF AT) were assayed 5 hours after instillation of hydrogen peroxide. In addition, to confirm the impairing effects of the activation of PLA2 associated with endogenous oxidative stress, lung weight/body weight ratio(Lx10(-3)/B), protein contents(mg/two lungs) in bronchoalveolar lavage(BAL) were measured. As neutrophilic respiratory burst has been known to play a pivotal role in the genesis of endogenous oxidative stress associated with acute inflammatory lung injury, BAL neutrophils counts and level of lung myelperoxidase(MPO) were measured after hydrogen peroxide insult. Morphological and histochemical studies were also performed to identify the effect of the endogenous oxidative stress. RESULT: Five hours after hydrogen peroxide instillation, lungs showed marked infiltration of neutrophils and increased weight. Protein contents in BAL increased significantly compared to those of normal rats. PLA2 activity was enhanced in the hydrogen peroxide instilled group. Interestingly, the accelerated production of platelet activating factor(PAF) was confirmed by the increased activity of lysoPAF AT in the H2O2 employed lung. Morphologically, light microscopic findings of lungs after instillation of hydrogen peroxide showed atelectasis and infiltration of inflammatory cells, which was thought to be caused by lipid mediators produced by PLA2 activation. In cerium chloride cytochemical electron microscopy, dense deposits of cerrous perhydroxide were identified. In contrast, no deposit of cerrous perhydroxide was found in the normal lung. CONCLUSION: As all these findings were consistent with the lung injury caused by neutrophilic oxidative stress, it is suggested that the activation of PLA2 by oxidants might participate in the genesis of endogenous oxidative stress. Collectively, the positive feedback loop between oxidative stress and PLA2 activation may participate in the pathogenesis of Adult Respiratory Distress Syndrome(ARDS).

Oxidative regeneration of carbonyl compounds from thieraza derivatives using cerium ammonium nitrate [CAN]

Oxidation of aromatic aldehyde oximes, oxime ethers, N, N- dimethylhydrazones and semicarbazones with CAN resulted in regeneration of the parent carbonyl compounds in high yields