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1.
Arq. bras. oftalmol ; 87(2): e2021, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1527829

RESUMO

ABSTRACT Purpose: Trimethylamine N-oxide serum levels have been associated with type 2 diabetes mellitus and its complications. The current study aimed to find out if plasma trimethylamine N-oxide level may be a novel marker in the diagnosis of diabetic retinopathy and if it can be used in the differential diagnosis of diabetic and nondiabetic retinopathy. Methods: The study included 30 patients with diabetic retinopathy, 30 patients with nondiabetic retinopathy, 30 patients with type 2 diabetes mellitus without retinopathy, and 30 healthy control participants. Biochemical parameters, serum IL-6, TNF-α, and trimethylamine N-oxide levels were measured in all participants. Results: Trimethylamine N-oxide level was significantly higher in diabetic retinopathy than in the other groups (p<0.001). There was no significant difference in trimethylamine N-oxide levels between nondiabetic retinopathy and control or type 2 diabetes mellitus Groups. There was a significant positive correlation between trimethylamine N-oxide level and elevated FPG, BMI, HOMA-IR score, BUN, IL-6, and TNF-α levels. Conclusion: The current study showed that the trimethylamine N-oxide level is elevated in diabetic retinopathy. These findings suggest that serum trimethylamine N-oxide level might be a novel marker for diabetic retinopathy, and it might be used in the differential diagnosis of diabetic and nondiabetic retinopathy.


RESUMO Objetivo: Os níveis séricos de N-óxido de trimetilamina têm sido associados ao diabetes mellitus tipo 2 e suas complicações. O presente estudo tem como objetivo responder a duas questões, entre elas: O nível plasmático de N-óxido de trimetilamina poderia ser um novo marcador no diagnóstico de retinopatia diabética? e Ele poderia ser utilizado no diagnóstico diferencial de retinopatia diabética e não diabética? Métodos: Trinta pacientes com retinopatia diabética, 30 pacientes com retinopatia não diabética, 30 pacientes com diabetes mellitus tipo 2 sem retinopatia e 30 participantes saudáveis do grupo controle foram incluídos no estudo. Parâmetros bioquímicos, níveis séricos de IL-6, de TNF-α e de N-óxido de trimetilamina foram medidos em todos os participantes. Resultados: O nível de N-óxido de trimetilamina foi significativamente maior na retinopatia diabética do que nos outros grupos (p<0,001). Não houve diferença significativa no nível de N-óxido de trimetilamina entre o grupo de retinopatia não diabética, do grupo controle ou do grupo de diabetes mellitus tipo 2. Houve uma correlação positiva significativa entre o nível de N-óxido de trimetilamina e os níveis elevados de FPG, IMC, HOMA-IR, BUN, IL-6 e TNF-α. Conclusão: O estudo atual mostrou que o nível de N-óxido de trimetilamina encontra-se elevado na retinopatia diabética. Esses achados sugerem que o nível sérico de N-óxido de trimetilamina pode ser um novo marcador na retinopatia diabética, podendo ser usado no diagnóstico diferencial de retinopatia diabética e não diabética.

2.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 155-162, 2020.
Artigo em Chinês | WPRIM | ID: wpr-862707

RESUMO

<b>Objective::To establish an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) for the simultaneous determination of 15 pyrrolidine alkaloids (PAs) and their nitrogen oxides, and determine the content of the 15 PAs in the 15 batches of Farfarae Flos samples obtained from different sources, in order to understand the distribution status of these 15 PAs in Farfarae Flos from different sources, and provide relevant references for the safe and rational use of this medicinal materials. <b>Method::The method was achieved by Agilent Eclipse Plus C<sub>18</sub> column (3.0 mm×150 mm, 1.8 μm) using a mobile phase made up of 0.05%formic acid and 2.5 mmol·L<sup>-1</sup> ammonium formate in water (A)-0.05%formic acid and 2.5 mmol·L<sup>-1</sup> ammonium formate in methanol(B). The flow rate and the injection volume were 0.4 mL·min<sup>-1</sup> and 2 μL, respectively. The column temperature was 40 ℃. The instrument was Agilent 1290-6470 QQQ ultra high performance liquid chromatography-triple quaternary bar mass spectrometer. The components were detected in multiple reaction monitoring mode by mass spectrometry with ionizationmode of ESI<sup>+</sup>. The content of the components measured in the samples was calculated by using the external standard method, and the difference between samples was analyzed based on RSD of different components. <b>Result::The established method had a high sensitivity and good separation degree. The results of methodological investigation met the requirements. The results showed that all of the 15 batches of Farfarae Flos contained PAs and their nitrogen oxides. These PAs had almost the same types of structure. There were significant differences in the content and distribution of PAs in Farfarae Flos obtained from different sources. <b>Conclusion::In general, Farfarae Flos contains pyrrolidine alkaloids and their nitrogen oxides. Senkirkine with a significant hepatotoxicity is the main compound. The content determination of PAs will provide scientific fundaments for the safe and effective use of Farfarae Flos.

3.
Ciênc. agrotec., (Impr.) ; 42(1): 80-92, Jan.-Feb. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-890664

RESUMO

ABSTRACT Portable X-ray fluorescence spectrometer (pXRF) has been recently adopted by the Soil Science community for uses in both field and laboratory, obtaining the total content of several chemical elements in a few seconds. Sulfuric acid digestion is an expensive and time-consuming laboratory analysis that provides contents of Fe2O3, Al2O3, SiO2, TiO2 and P2O5, important for soil studies. Due to few pXRF studies in tropical soils, this work aimed to compare contents of Fe2O3, Al2O3, SiO2, TiO2 and P2O5 obtained by pXRF with sulfuric acid digestion results, and to evaluate the effects of varying forms of preparing soil samples and scanning with pXRF on the resulting values in Brazilian soils. Soils were scanned in five conditions in-field (in situ) and in laboratory, evaluating varying sample preparation methods, particle sizes and soil moisture. Four pXRF scanning operational modes were tested. Linear regressions were adjusted between results of pXRF and sulfuric acid digestion. Equations were validated with an independent set of samples. Statistical analyses compared the methods of preparing the samples. Adequate linear models reached R2 of 0.99 and 0.89 for Fe2O3 and TiO2, respectively. Validation promoted R2 greater than 0.97 and RMSE and ME close to zero for both oxides. Statistical differences of pXRF results were found among the methods of preparing samples. pXRF spectrometer has great potential to obtain Fe2O3 and TiO2 content rapidly and economically with high correspondence with laboratory results of sulfuric acid digestion analysis. Varying methods of preparing the samples promote differences in the results of pXRF.


RESUMO O espectrômetro portátil de fluorescência de raios-X (pXRF) foi recentemente adotado pela Ciência do Solo, para uso em campo e laboratório, para obtenção do conteúdo total de vários elementos químicos em poucos segundos. A digestão com ácido sulfúrico é uma análise laboratorial cara e demorada que fornece teores de Fe2O3, Al2O3, SiO2, TiO2 e P2O5, importantes para estudos sobre solos. Devido aos poucos estudos sobre o pXRF em solos tropicais, este trabalho objetivou comparar os teores de Fe2O3, Al2O3, SiO2, TiO2 e P2O5 obtidos pelo pXRF com os resultados de digestão com ácido sulfúrico e avaliar os efeitos de diferentes formas de preparo de amostras de solo e leitura com o pXRF sobre seus resultados para solos brasileiros. Os solos foram submetidos a leituras com o pXRF em cinco condições, em campo (in situ) e em laboratório, avaliando variados métodos de preparo de amostras, tamanhos de partículas e umidade do solo. Quatro modos de operação do pXRF foram testados. Regressões lineares foram ajustadas entre os resultados do pXRF e digestão com ácido sulfúrico. As equações foram validadas com um conjunto independente de amostras. Análises estatísticas compararam os métodos de leitura de amostras. Modelos lineares adequados atingiram R2 de 0,99 e 0,89 para Fe2O3 e TiO2, respectivamente. A validação promoveu R2 maior que 0.97 e RMSE e ME próximos a zero para ambos os óxidos. Foram encontradas diferenças estatísticas dos resultados do pXRF entre os métodos de preparo de amostras. O pXRF possui um grande potencial para obter rápida e economicamente os teores de Fe2O3 e TiO2 com elevada correspondência com os resultados laboratoriais da análise da digestão com ácido sulfúrico. Métodos variáveis ​​de preparo das amostras promovem diferenças nos resultados de pXRF.

4.
Chinese Journal of Nuclear Medicine and Molecular Imaging ; (6): 19-24, 2016.
Artigo em Chinês | WPRIM | ID: wpr-491505

RESUMO

Objective To track the migration and incorporation of intravenously injected, magneti?cally labeled endothelial progenitor cells ( EPCs) from mouse bone marrow into the blood vessels in a rapid?ly growing HCC model by microMR (7.0 T). Methods This study was approved by the Institutional Com?mittee on Animal Research. H22 hepatic ascitic cancer cells was directly injected into the left liver lobe of BALB/c nude mice ( n=15) . EPCs derived from bone marrow of C57BL/6 mice were isolated and cultured. The third passage EPCs were collected and labeled with 25 μg/ml superparamagnetic iron oxide ( SPIO) and poly?l?lysine (PLL) complex (SPIO?PLL). MTT assay and flow cytometry were used to evaluate the difference of growth curve and apoptosis between labeled and unlabeled EPCs. EPCs labeled with SPIO?PLL were injected into mice via tail vein in experiment group (on the 3rd day after establishing HCC model) (n=15) and control group (n=6). The signal changes of tumor (the 1st, 3rd and 7th day after transplantation) were observed by microMR. Prussian blue staining and immunohistochemistry staining of CD31 were per?formed. MRI findings were confirmed by histomorphology. Two?sample t test was used to analyze the data. Results Single tumor was showed in the liver of all mice 3 d after establishing models. Labeling with SPIO?PLL at a concentration of 25μg/ml did not alter cell growth curve ( measured by MTT assay;t=0.281, P>0.05) and cell apoptosis (analyzed by flow cytometry). The apoptosis rates of SPIO?PLL labeled and un?labled EPCs were (12.31±1.43)% and (11.57±1.24)% in early stage, and (0.55±0.07)% and (0.49± 0?05)% in late stage. No significant differences were observed between them (t=0.967, 1.060; both P>0?05) . Migration and incorporation of transplanted and labeled cells into tumor were documented with in vivo microMR as low signal intensity at the tumor periphery as early as the 3rd day after EPCs administration in preformed tumors (4/5). Prussian blue staining showed iron?positive cells at the sites corresponding to low signal intensity on MRI. The positive cells expressing CD31 existed in intratumoral and peritumoral vessels. There was no signal change in control group at all time points. Conclusions MRI can demonstrate the in?corporation of magnetic labeled mouse EPCs into the implanted hepatoma. It may be helpful for early diagno?sis and therapy of liver tumor.

5.
Braz. j. med. biol. res ; 48(12): 1130-1135, Dec. 2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-762911

RESUMO

Exposure to nitrogen oxides (NOx) emitted by burning fossil fuels has been associated with respiratory diseases. We aimed to estimate the effects of NOx exposure on mortality owing to respiratory diseases in residents of Taubaté, São Paulo, Brazil, of all ages and both sexes. This time-series ecological study from August 1, 2011 to July 31, 2012 used information on deaths caused by respiratory diseases obtained from the Health Department of Taubaté. Estimated daily levels of pollutants (NOx, particulate matter, ozone, carbon monoxide) were obtained from the Centro de Previsão de Tempo e Estudos Climáticos Coupled Aerosol and Tracer Transport model to the Brazilian developments on the Regional Atmospheric Modeling System. These environmental variables were used to adjust the multipollutant model for apparent temperature. To estimate association between hospitalizations owing to asthma and air pollutants, generalized additive Poisson regression models were developed, with lags as much as 5 days. There were 385 deaths with a daily mean (±SD) of 1.05±1.03 (range: 0-5). Exposure to NOx was significantly associated with mortality owing to respiratory diseases: relative risk (RR)=1.035 (95% confidence interval [CI]: 1.008-1.063) for lag 2, RR=1.064 (95%CI: 1.017-1.112) lag 3, RR=1.055 (95%CI: 1.025-1.085) lag 4, and RR=1.042 (95%CI: 1.010-1.076) lag 5. A 3 µg/m3 reduction in NOx concentration resulted in a decrease of 10-18 percentage points in risk of death caused by respiratory diseases. Even at NOx concentrations below the acceptable standard, there is association with deaths caused by respiratory diseases.


Assuntos
Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Poluentes Atmosféricos/toxicidade , Poluição do Ar/efeitos adversos , Exposição Ambiental/efeitos adversos , Óxido Nítrico/toxicidade , Transtornos Respiratórios/etiologia , Transtornos Respiratórios/mortalidade , Poluição do Ar/análise , Brasil/epidemiologia , Monóxido de Carbono/toxicidade , Ozônio/toxicidade , Distribuição de Poisson , Material Particulado/toxicidade , Risco , Sensação Térmica
6.
Journal of International Pharmaceutical Research ; (6): 606-609, 2015.
Artigo em Chinês | WPRIM | ID: wpr-845734

RESUMO

Objective To elevated the decontamination properties of commercial nanoscale metal oxides against chemical warfare agents (CWA), and provide more foundation for the satisfactory materials of CWA decontamination. Methods Some nanocrystals of commercial metal oxides such an MgO, TiO2, ZnO and zinc nickel ferrite compound had been chosen to compare their decontamination properties. The nanocrystals were mixed with three representative compounds, sulfur mustard (HD), soman (GD) and SI 2-diisopropylaminoethyl) O-ethyl methylphosphonothioate (VX) at room temperature and natural light. The analogous experiments were conducted without addition of nanocrystals as negative control. After a fixed time, the samples were then analyzed by the methods of T-135, Schoeneman reaction and conversion method to determine the content of CWA. The decontamination properties of nanocrystals were compared with negative control. Results The chosen nanoscale metal oxides excepted nanoscale MgO had good decontamination properties against HD, and they all could decontaminate GD quickly. Nanoscale TiO2 had superior decontamination properties against GD and HD. At the room temperature and natural light, HD was completely decontaminated within 20 hours and GD was completely decontaminated within 4 hours by nanoscale TiO2. The nanocrystals of metal oxides didn't decontaminate VX effectively. Compared to the activated clay group, nanoscale MgO had superior decontamination properties against VX over other nanocrystals (P<0.05), but the percentage of degradation was lower than 20% within 7 h. Conclusion The chosen nanoscale TiO2 has superior decontamination properties against GD and HD than others in natural condition, but it isn't a promising agent for the decontamination of VX.

7.
Journal of International Pharmaceutical Research ; (6): 606-609, 2015.
Artigo em Chinês | WPRIM | ID: wpr-478262

RESUMO

Objective To elevated the decontam ination properties of commercial nanoscale metal oxides against chemical warfare agents (CWA), and provide more foundation for the satisfactory materials of CWA decontamination. Methods Some nanocrystals of commercial metal oxides such an MgO, TiO2, ZnO and zinc nickel ferrite compound had been chosen to compare their decontamination properties. The nanocrystals were mixed with three representative compounds, sulfur mustard (HD), soman (GD) and S-(2-diisopropylaminoethyl) O-ethyl methylphosphonothioate (VX) at room temperature and natural light. The analogous experiments were conducted without addition of nanocrystals as negative control. After a fixed time, the samples were then analyzed by the methods of T-135, Schoeneman reaction and conversion method to determine the content of CWA. The decontamination properties of nanocrystals were compared with negative control. Results The chosen nanoscale metal oxides excepted nanoscale MgO had good decontamination properties against HD, and they all could decontaminate GD quickly. Nanoscale TiO2 had superior decontamination properties against GD and HD. At the room temperature and natural light, HD was completely decontaminated within 20 hours and GD was completely decontaminated within 4 hours by nanoscale TiO2. The nanocrystals of metal oxides didn′t decontaminate VX effectively. Compared to the activated clay group, nanoscale MgO had superior decontamination properties against VX over other nanocrystals (P<0.05), but the percentage of degradation was lower than 20% within 7 h. Conclusion The chosen nanoscale TiO2 has superior decontamination properties against GD and HD than others in natural condition, but it isn′t a promising agent for the decontamination of VX.

8.
Chinese Journal of Nuclear Medicine and Molecular Imaging ; (6): 139-144, 2015.
Artigo em Chinês | WPRIM | ID: wpr-466381

RESUMO

Objective To determine the optimal procedure for preparation of the SPIO nanoparticles modified by dextran polylysine,and to evaluate the quality of this product.Methods The optimal preparation procedure of four factors (solution pH value,dextran concentration,reaction temperature and stirring rate) affecting SPIO hydrodynamic size were obtained through orthogonal experiments (3 levels).SPIO nanoparticles were synthesized under an optimum procedure.The shape and hydrodynamic size were detected by transmission electron microscope (TEM) and Malvern Zetasizer respectively.The content of Fe was detected by atomic absorption spectrophotometer,while chemical structures of SPIO nanoparticles were characterized and analyzed by infrared spectroscopy (IR) method.X-ray powder diffraction method was used to identify the ingredients,and the magnetic parameters were measured by vibrating sample magnetometer.Furthermore,experiments with ovarian cancer cells were performed to primarily validate the magnetic property of SPIO nanoparticles.Results The results of the orthogonal experiments showed that the optimum preparation procedure was as follows:dextran concentration of 10 mg/ml,pH 10,reaction temperature of 80 ℃ and stirring rate of 600 r/min.The TEM results showed the SPIO nanoparticles were in spherical shape,homogeneously distributed and uniform in size,and the mean diameter was 7.0 nm.The content of Fe was (12.36±0.08) g/L.The IR results clearly showed that the Fe3O4 was coated by dextran successfully.The Xray powder diffraction method showed that the sample contained Fe3O4 and the magnetism parameters indicated that the sample had superparamagnetism.The experiments with ovarian cancer cells demonstrated that SPIO nanoparticles could enter into the cells and then the cells had certain magnetic properties.Conclusions The SPIO nanoparticles synthesized under the optimal procedure are stable,small in size,with good dispersion and are feasible to enter into cells for rendering certain magnetic properties.This study has provided a good foundation and potential for further research.

9.
Artigo em Inglês | IMSEAR | ID: sea-167791

RESUMO

Associated red and black soils of the transect from Hira region of Hatti schist belt were studied for their properties. Soils were moderately deep to deep, reddish brown (5YR 3/4) to dark black (10YR3/2), clay in texture. The pH ranged from 7.56 to 7.7, EC from 0.4 to 0.44dSm-1, low to medium in organic carbon, moderate in CEC (40.1 – 54.3 c mol (p+) kg-1). Free iron oxides ranges from (0.6-3.2%), Na2CO3 extractable free silicon ranges from (0.4-3.1%) and Na2CO3 extractable free aluminium ranges from (0.2 - 2.5%).

10.
Chinese Journal of Digestive Endoscopy ; (12): 645-649, 2014.
Artigo em Chinês | WPRIM | ID: wpr-457950

RESUMO

Objective To study the induction of nitrous oxide(N2 O)and to compare safety and effec-tiveness of conscious sedation by nitrous oxide inhalation and intravenous sedation with propofol for upper gas-trointestinal(UGI)endoscopy.Methods A total of 400 patients undergoing UGI endoscopy in our hospital from April 2013 to October 2013 were randomly assigned to two groups,N2 O inhalation group(n=200)and in-travenous propofol group(n=200).The systolic pressures,diastolic pressures,heart rates and oxygen satura-tion,onset time,procedure duration,degree of sedation,recovery time,length of hospital stay,complica-tions,satisfaction ratings of doctors and patients,and the number of patients willing to accept the examination again were analyzed.Results The mean time of ideal anesthesia state for N2 O was (3. 16 ±0. 65 )min and there was no difference between the male and female(3. 16 ±0. 71)min vs.(3. 16 ±0. 58)min,t=0. 006,P>0. 05).The mean concentration was (43. 68 ±5. 05 )%,which was higher in male than that in female [(45. 3 ±4. 99)% vs.(41. 46 ±4. 30)%,t=3. 042,P sures,diastolic pressures,heart rates and oxygen saturation of patients in the propofol group significantly re-duced during the procedure(P<0. 05),while the same measurements excluding oxygen saturation for those in the N2 O group significantly increased(P<0. 05 ).Compared with the propofol group,patients inhaling N2 O had significantly shorter recovery and hospital stay time,but a longer onset time and procedure duration(P<0. 05 ).Complications that occurred in some patients of propofol group included hyoxemia,hypotension,brady-cardia,while the major complication in the N2 O group was nausea.The satisfaction ratings of doctors or pa-tients and the number of patients willing to accept the examination again in N2 O group were smaller than those in propofol group(86 ±3. 7 vs.96 ±2. 6,87 ±2. 8 vs.98 ±1. 2,87%vs.99%,P<0. 05).Conclusion Both conscious sedation by N2 O inhalation and intravenous sedation with propofol are effective for diagnostic UGI en-doscopy,but the safety of the former is superior to the latter.The key to complete the conscious sedation by ni-trous oxide inhalation is to accurately identify the ideal anesthesia state of N2 O.It is significant to pay attention to the nine factors concerning safe and effective sedation during operation.

11.
Tianjin Medical Journal ; (12): 170-172, 2014.
Artigo em Chinês | WPRIM | ID: wpr-474592

RESUMO

Objective To explore the protective effect of co-treatment with antioxidants 4-hydroxy-2,2,6,6-tetra-methylpiperidine 1-oxyl (TEMPOL) and reduced glutathione (GSH) in pancreatic injury induced by intermittent hypoxia (IH) in mice. Methods Fifty male C57BL/6J mice were randomly divided into control group(CON), IH group (IH), IH+TEM-POL group (IH+TEMPOL), IH+GSH group (IH+GSH) and IH+TEMPOL+GSH group (IH+TEMPOL+GSH). After successful-ly prepared animal model, the insulin resistance (IR) level, pancreatic malondialdehyde (MDA) level,superoxide dismutase (SOD) activity,glutathione reductase (GR) concentration and pancreatic β-cell apoptosis were detected in five groups. Re-sults The blood glucose level was significantly increased in IH group than that in CON group (P0.05). Conclusion The co-treatment with the antioxidant TEMPOL and GSH can obviously protect IH-induced pancreatic injury in mice. However, there was no significant protective effect of TEMPOL or GSH alone on pancreatic injury.

12.
Rev. colomb. quím. (Bogotá) ; 42(1): 64-85, Jan.-Apr. 2013. ilus
Artigo em Espanhol | LILACS | ID: lil-729600

RESUMO

Óxidos mixtos de manganeso y cobalto, con relaciones molares M²++Mg2+ /M3+=3 y M2+/ Mg2+=1, fueron preparados por el método de coprecipitación. Los sólidos fueron caracterizados mediante las técnicas de difracción de rayos X (XRD), temperatura programada de reducción (TPR-H2) y adsorción de N2 en área superficial; éstos fueron empleados para la oxidación catalítica de una mezcla de dos compuestos orgánicos representativos de COVs: el tolueno y el 2-propanol. El óxido mixto de manganeso logró el 100% de oxidación de la mezcla de COVs, mientras que el óxido mixto de cobalto no alcanzó una oxidación total. El catalizador Mn-Mg-Al presentó las menores temperaturas de oxidación de tolueno y 2-propanol en la mezcla, haciéndolo el catalizador más eficiente. El desempeño catalítico superior de dicho óxido se asocia principalmente con su mejor comportamiento redox, comparado con el del óxido de cobalto. Con el fin de evaluar el efecto de la composición del reactivo, se estudió la oxidación catalítica individual de tolueno y 2-propanol sobre el óxido mixto de manganeso. El catalizador fue activo en la oxidación de los dos COVs individuales, pero el tolueno fue el compuesto más difícil de oxidar. Dicho catalizador mostró 100% de conversión del tolueno hacia CO2, mientras que el 2-propanol produjo primero acetona, la cual posteriormente fue oxidada hasta CO2. Las temperaturas de oxidación de los componentes en la mezcla de COVs fueron superiores que en la conversión individual de tolueno y 2-propanol. Este resultado sugiere un posible efecto inhibitorio en la oxidación de 2-propanol cuando se tienen mezclas de los COVs.


Manganese and cobalt mixed oxides with M2++Mg2+/M3+=3 y M2+/Mg2+=1 ratios were obtained by the coprecipitation method. The solids were characterized using X-ray diffraction (XRD), temperature-programmed reduction (H2-TPR), N2 adsorption and in the catalytic oxidation of two VOCs: toluene and 2-propanol. Manganese mixed oxide reached 100% conversion of the mixture of VOCs while cobalt mixed oxide did not achieve a complete oxidation. The catalyst Mn-Mg-Al showed the lowest temperature oxidation of toluene and 2-propanol in the mixture. The highest performance of the oxide catalyst Mn-Mg-Al is associated with the better redox potential in the manganese catalyst. Manganese mixed oxide was active in the oxidation of the single VOCs, where the scale of difficulty to oxidize the different organic compounds evaluated was: 2-propanol < toluene. The mixed oxide showed 100% conversion to CO2 in the oxidation of toluene, while the 2-propanol was first oxidized to acetone. It suggests that there is an inhibitory effect on the oxidation of 2-propanol in the mixture of VOCs.


Óxidos mistos de cobalto e manganês com relações M2++Mg2+/M3+=3 y M2+/ Mg2+=1 foram preparados pelo método de coprecipitação. Os sólidos foram caracterizados pelas técnicas de difração de raios-X (XRD), temperatura programada de redução (TPR-H2), área superficial adsorção do N2 e na oxidação catalítica de dois compostos orgânicos representativos (COVs): tolueno e 2-propanol. O catalisador Mn-Mg- Al apresentou as menores temperaturas de oxidação da mistura, fazendo-lo o catalisador mais eficiente. O desempenho catalítico superior do óxido Mn-Mg-Al está associado principalmente a seu melhor desempenho redox em comparação com o óxido de cobalto. Mn-Mg-Al catalisador foi ativo na oxidação dos dois individuais COVs, sendo o tolueno o composto mais difícil de oxidar seguido do 2-propanol. Óxidos mistos de manganês mostro 100% de conversão até CO2 para tolueno, enquanto que o 2-propanol produz em primeiro lugar acetona, que posteriormente é oxidada a CO2. Temperaturas de oxidação dos componentes da mistura de compostos orgânicos voláteis é maior do que a única conversão de tolueno e 2-propanol. Este resultado sugeriu um possível efeito inibitório sobre a oxidação de 2-propanol ao ter misturas de COV.

13.
Chinese Journal of Nuclear Medicine and Molecular Imaging ; (6): 19-23, 2013.
Artigo em Chinês | WPRIM | ID: wpr-431115

RESUMO

Objective To manufacture magnetic microbubbles with dual-response to ultrasound and magnetic fields.Methods Microbubbles of ultrasound contrast agent (ST68) based on a surfactant were prepared by the acoustic cavitation method.Fe3O4 magnetic nanoparticles with negative charge were synthesized using the polyol procedure.Magnetic microbubbles were generated by depositing polyethylenimine and Fe3O4 magnetic nanoparticles alternately onto the microbubbles using the layer-by-layer self-assembly.In vitro ultrasonography was performed on a silicone tube with/without magnetic microbubbles (3 × 108/ml) by a self-made device to observe the movement of magnetic microbubbles under the effects of magnetic field.In vivo imaging was performed on the kidney of New Zealand rabbits before and after the injection of magnetic microbubbles.Results The Fe3O4 nanoparticles carried a stable negative charge of (-24.6 ± 6.7) mV and more than 98% of the particles were less than 8 μm in diameter,meeting the size requirement of an ultrasound contrast agent for intravenous administration.There was no echoic signal in the silicone tube before injection of magnetic microbubbles,but there were strong echoic signals after injection.After applying a magnetic field,the magnetic microbubbles moved along the direction of the magnetic flux.In vivo ultrasound imaging could not visualize the kidney before injection of magnetic microbubbles,but could remarkably visualize the kidney after injection.Conclusions The magnetic microbubbles exhibit favorable magnetic targeting and ultrasound contrast enhancement characteristics.Such properties may serve as the foundation to study their potential for simultaneous diagnosis and treatment in the future.

14.
Braz. j. pharm. sci ; 47(3): 593-600, July-Sept. 2011. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-602676

RESUMO

The objective of this study was to prepare and evaluate chronotherapeutic drug delivery systems (ChrDDs) of torsemide. Compression coated tablets (CCT) containing torsemide in the core tablet were prepared by the compression coating technique with different grades of polyethylene oxide (PEO WSR 301 & 1105). The optimized formulations were characterised for tabletting parameters and drug polymer interaction by Fourier-Transform Infrared Spectroscopy (FTIR).The hardness of all the CCT using PEO WSR 301 & PEO WSR 1105 were in the range 6-8 kg/cm² & 5.5 to 7 kg/cm² respectively. Their friability values were <0.3 percent. All the CCT showed a clear lag time but finalized as per the predetermined lag time. As the amount of PEO was increased in the outer layer the drug released was delayed. The drug content of all the CCT was >99 percent. The FTIR studies showed no interaction throughout the process of development. Formulations of F7 and of P7 were considered optimized formulations since they yielded a predetermined lag time of 6h before burst release. Hence, these formulations can be exploited to achieve chronotherapeutic drug delivery systems of Torsemide for the treatment of hypertension at the time the patient needs it.


O objetivo deste estudo foi preparar e avaliar sistemas cronoterapêuticos de liberação de fármacos (ChrDDs) de torsemida. Comprimidos revestidos por compressão (CCT) contendo torsemida no (núcleo) foram preparados pela técnica de revestimento por compressão, com diferentes categorias de óxido de polietileno (PEO WSR 301 & 1105). As formulações otimizadas foram caracterizadas por parâmetros de compressão e interação fármaco polímero por Infravermelho com Transformada de Fourier (FTIR). A dureza dos CCT utilizando PEO WSR 301 e PEO WSR 1105 foi entre 6-8 kg/cm² e 5,5 a 7 kg/cm², respectivamente. Os valores de friabilidade foram <0,3 por cento. Todos os CCT mostraram claro tempo de retardo, mas finalizaram de acordo com o tempo de retardo pré-determinado. À medida que a quantidade de PEO aumentava na camada mais externa, a liberação do fármaco era retardada. O teor de fármaco em todos os CCT foi >99 por cento. Os estudos de FTIR mostraram que não h[a interação durante o processo de desenvolvimento. As formulações F7 e P7 foram consideradas otimizadas, uma vez que resultaram em tempo de retardo pré-determinado de 6 h antes da liberação por meio de explosão. Dessa forma, estas formulações podem ser exploradas para se obter sistemas de liberação.


Assuntos
Diuréticos/agonistas , Diuréticos/farmacocinética , Diuréticos/química , Desenvolvimento Experimental , Técnicas In Vitro , Cronofarmacoterapia , Preparações de Ação Retardada/química
15.
Chinese Journal of Ultrasonography ; (12): 625-627, 2011.
Artigo em Chinês | WPRIM | ID: wpr-416502

RESUMO

Objective To study the feasibility of the Fe3O4-loaded lipid perfluorooctylbromide nanoparticles (Fe3O4-PFOB) for enhanced ultrasound imaging.Methods The Fe3O4-PFOB nanoparticles,incubated with RAW264.7 macrophage cells,were monitored by microscope and ultrasound.Twelve SD rats were randomized into two groups,Fe3O4-PFOB group and PFOB group.Ultrasound imaging of rats' liver was performed before and after intravenous injection of the contrast agents.The liver echogenic intensity was quantified by DFY ultrasound quantified system analysis.Results Incubation of the Fe3O4-PFOB nanoparticles with macrophages resulted in the uptake of Fe3O4-PFOB by macrophages.Macrophages loaded with Fe3O4-PFOB exhibited enhanced echogenicity in vitro.In in vivo imaging,Fe3O4-PFOB produced better and prolonged ultrasound enhancement of rats' liver compared to PFOB nanoparticles.Conclusions Fe3O4-PFOB nanoparticles could enhance ultrasound imaging and may potentially serve as a multimodal probe for ultrasound,CT and MR imaging.

16.
São Paulo; s.n; 2011. 105 p. ilus, tab, graf.
Tese em Português | LILACS | ID: lil-639138

RESUMO

O ovo é importante como alimento e como matéria-prima industrial. Tem alto conteúdo de colesterol, o qual, por sua vez, está sujeito à oxidação. Os óxidos formados interferem na morfologia e função da membrana celular, inibem a biossíntese do colesterol, e são aterogênicos, citotóxicos, mutagênicos e cancerígenos. O processamento e o armazenamento levam à oxidação do colesterol. O presente trabalho teve como objetivos (a) a caracterização e avaliação do ovo líquido integral (OLI) em relação ao armazenamento da matéria-prima; (b) a avaliação do ovo líquido integral (OLI), do ovo líquido integral pasteurizado (OLIP), do ovo integral em pó atomizado (OIPA) e do ovo integral em pó atomizado armazenado, em relação à estabilidade oxidativa do colesterol; e (c) a avaliação do efeito da adição de antioxidantes naturais durante o processamento do ovo integral em pó atomizado, em relação à estabilidade oxidativa do colesterol. O OLI produzido a partir de matéria-prima armazenada por 30 dias, a 4ºC, não foi afetado quanto à estabilidade oxidativa do colesterol. A pasteurização e a atomização, realizadas em condições de laboratório, não levaram ao comprometimento oxidativo do colesterol. Foi constatada oxidação significativa do colesterol no OIPA, obtido em condições de laboratório, quando armazenado por 90 dias, a 25ºC, na ausência de luz. Os antioxidantes naturais comerciais GUARDIAN® Rosemary Extract (RE) e o GUARDIANTM TOCO 70 (TOCO 70) não foram efetivos na prevenção da oxidação induzida do colesterol, quando adicionados (antes ou depois da atomização) ao ovo integral em pó atomizado obtido em condições de laboratório, armazenado por 21 dias, a 25°C, na ausência de luz.


Egg is important as food and as industrial raw material. It has high cholesterol, which, in turn, is subject to oxidation. Cholesterol oxides interfere with morphology and function of cell membrane, inhibit cholesterol biosynthesis, and are atherogenic, cytotoxic, mutagenic and carcinogenic. Processing and storage lead to oxidation of cholesterol. Present study aimed (a) characterization and evaluation of liquid whole egg (OLI) in relation to storage of raw material; (b) evaluation of liquid whole egg (OLI), liquid pasteurized whole egg (OLIP), atomized powder whole egg (OIPA) and stored atomized powder whole egg, relative to cholesterol oxidative stability, and (c) evaluation of natural antioxidants addition's effect in processing of atomized powder whole egg, relative to cholesterol oxidative stability. OLI produced from raw materials stored for 30 days, at 4°C, was not affected on cholesterol oxidative stability. Pasteurization and atomization, performed under laboratory conditions, did not lead to significant cholesterol oxidation. It has been found significant cholesterol oxidation in OIPA, obtained under laboratory conditions, when stored for 90 days at 25°C in absence of light. Commercial natural antioxidants GUARDIAN® Rosemary Extract (RE) and GUARDIANTMTOCO 70 (TOCO 70) were not effective in prevention of cholesterol induced oxidation when added (before or after spraying) to atomized powder whole egg obtained under laboratory conditions, stored for 21 days at 25°C in absence of light.


Assuntos
Colesterol/análise , Conservação de Alimentos/métodos , Estresse Oxidativo , Ovos/análise , Antioxidantes/química , Armazenamento de Alimentos
17.
Academic Journal of Second Military Medical University ; (12): 167-170, 2010.
Artigo em Chinês | WPRIM | ID: wpr-840943

RESUMO

Objective: To investigate the activation of p38 signaling transduction cascade in renal ischemia reperfusion injury (IRI) and to study the effect of tempol, a free oxygen radical scavenger, on p38 activation. Methods: Male Sprague-Dawley rats were randomly divided into sham-operation group (n=10), IRI group (n=45) and IRI + tempol group(n=10). Animal IRI model was created by renal pedicle ligation (50 min) of the left kidney along with a contralateral nephrectomy followed by 2 h reperfusion. Rats were sacrificed on 0, 5, 10, 15, 30, 45 min, 1 and 2 h after renal reperfusion. Animals in IRI + tempol group were pretreated with tempol (100 mg/kg) 1 h before undergoing the same protocol as in IRI group; the kidney was harvested after 45 min of reperfusion. Animals in the sham-operation group were subjected to contralateral nephrectomy without renal pedicle ligation and were sacrificed 45 min later. The renal p38 activities of the 3 groups were determined by Western blotting analysis. Malondialdehyde (MDA) content was detected and pro-inflammatory cytokine TNF-α, IL-1β levels were analyzed by ELISA. Results: Activation of p38 was observed in the kidney as early as 5 min after reperfusion and reached its peak 45 min after reperfusion and remained to be activated until 2 h after reperfusion(P<0.05). The activities of renal p38 in IRI and IRI + tempol group were markedly increased compared with that of the sham-operation group(both P<0.05). Pretreatment with tempol significantly inhibited IRI-induced p38 activation(P<0.05); it also decreased MDA activity and TNF-α and IL-1β levels (both P<0.05). Conclusion: Our results demonstrate that reactive oxygen species-mediated p38 activation plays an essential role in IRI-induced renal inflammatory damage in rats, suggesting that inhibition of p38 activation by tempol may be used for prophylaxis and treatment of IRI.

18.
São Paulo; s.n; 2009. 117 p. ilus, tab, graf.
Tese em Português | LILACS | ID: lil-594948

RESUMO

O ovo em pó é amplamente utilizado na indústria de alimentos, sendo reconhecidamente rico em óxidos de colesterol (OsC) devido às altas temperaturas utilizadas durante o processo. O armazenamento em embalagens inadequadas, presença de ar e a alta concentração lipídica do produto são fatores adicionais para sua formação. Os óxidos de colesterol formados, por sua vez, apresentam propriedades biológicas prejudiciais à saúde, relacionadas com a aterogenicidade, citotoxicidade, carcinogenicidade e mutagenicidade, além de outras manifestações que prejudicam a biossíntese do colesterol no organismo e a permeabilidade da membrana celular. Os objetivos do estudo foram caracterizar amostras comerciais de ovo integral em pó e a ocorrência de óxidos de colesterol, avaliar o efeito do processamento por atomização comercial na estabilidade oxidativa do colesterol e de ácidos graxos, e avaliar o efeito da adição de tocoferóis (aditivo comercial) ao ovo em pó armazenado (90 dias) à temperatura ambiente sobre a estabilidade oxidativa do colesterol. Foram encontrados 7-cetocolesterol (7-Ceto) e 25-hidroxicolesterol (25-OH) em todas as marcas analisadas, mas somente o 7-Ceto teve um aumento expressivo durante o armazenamento de até 180 dias, independente da marca. A atomização gerou redução das TBARS e dos carotenóides totais somente em alguns lotes analisados e redução expressiva nos ácidos graxos livres e fenólicos totais em todos os lotes. Com relação aos óxidos de colesterol, não houve o efeito esperado. Houve aumento do 7-Ceto, 7α-hidroxicolesterol e 7β-hidroxicolesterol somente em poucos lotes. A adição do antioxidante (AO) não evitou o aumento das TBARS e dos ácidos graxos livres, ou redução dos carotenóides totais ao longo do tempo (90 dias). Apesar da atomização não causar o efeito esperado nos OsC, o armazenamento aumentou significativamente os valores de 7-Ceto a partir dos 60 dias na maioria dos lotes. Não foi encontrada diferença estatística entre os valores de...


Egg powder is widely used in food industry, being recognized as rich in cholesterol oxides (Cops) due to the high temperatures used during the process. The storage in inadequate packaging, the presence of air and high lipid concentration of the product are additional factors for their formation. The cholesterol oxides formed have biological properties harmful to health, like atherogenicity, cytotoxicity, mutagenicity and carcinogenicity, and other events that affect the cholesterol biosynthesis in the body and the membrane permeability. The aim of this study was to evaluate the occurrence of cholesterol oxides in commercial product, the effect of atomization in the liquid egg, and oxidative stability of cholesterol in egg powder storage with the addition of an commercial antioxidant (GUARDIANTM TOCO 70). It was found 7- ketocholesterol (7-k) and 25-hydroxycholesterol (25-OH) in all brands tested, but only the 7-k increased significantly during the storage of up to 180 days, regardless of brand. The spray-dryer generated reduction of TBARS and total carotenoids only in some samples analyzed and significant reduction in free fatty acids and total phenolics in all lots. There wasnt the expected effect for the cops. There was an increase of 7-k, 7α-hydroxycholesterol and 7β-hydroxycholesterol only in a few lots. The addition of antioxidant (AO) did not prevent the increase in TBARS and free fatty acids, or reduction of total carotenoids over time (90 days). Despite the spray-dryer does not cause the expected effect on the Cops, storage significantly increased the values of 7-k from 60 days in most lots. There was no statistical difference between the values of 25-OH due to their high variation. However the addition of AO reduced the formation of some Cops and TBARS in relation to its control over the same period, showing a significant improvement in the final product...


Assuntos
Colesterol/análise , Ovos , Manipulação de Alimentos , Conservação de Alimentos , Armazenamento de Alimentos , Óxidos/análise , Tocoferóis/análise , Análise de Alimentos , Ciências da Nutrição
19.
Chinese Journal of Geriatrics ; (12): 593-596, 2009.
Artigo em Chinês | WPRIM | ID: wpr-393983

RESUMO

Objective To explore the establishment of skin photoaging model and the protective effects of nitroxide tempol on skin in guinea pig. Methods The guinea pig skin photoageing model was established by using solar-simulaten radiation (SSR). Dermal structure was observed with hematoxylin-eosin staining. The structure and expression of elastic fiber were analyzed by Weigert's staining. The uhrastructure of dermal fibroblasts and elastic fiber were observed by electron microscopy. Tempol was used before each exposure at the concentration of 5 mg/ml or 0. 5 mg/ml, and the protective effects of tempol on skin were assessed. Results After seventeen weeks' exposure, there was typical "solar elastosis" damage in the upper dermis. Mature elastic fibers were severely degraded and there was large amount of elastotic material accumulated in the upper dermis. Dermal fibroblasts appeared metabolically hyperactive and mitochondria in the cells were damaged. Some cells even broke up. Tempol at the concentration of 5 mg/ml or 0. 5 mg/ml could prevent photodamage of the photoageing model in the dermis, and Tempol at the concentration of 5 mg/ml had stronger protective effects. Conclusions Guinea pig can be applied as an useful animal model of skin photoageing. Antioxidant tempol has photoprotective effects on photodamage of the photoageing model in guinea pig and can be used as an anti-photoageing agent.

20.
Chinese Journal of Medical Imaging Technology ; (12): 2174-2177, 2009.
Artigo em Chinês | WPRIM | ID: wpr-471438

RESUMO

Objective To track the magnetically labeled bone marrow mononuclear stem cells (BM-MNCs) in canine myocardial infarction (MI) model with MR. Methods BM-MNCs were labeled with Feridex effectively in vitro and then injected intramyocardially in 8 MI model dogs. Serial MR was performed with 1.5T MR scanner to show the location of the labeled cells compared with histology. Results The injection sites of labeled BM-MNCs could be located on the 1st and 2nd week, but disappeared on the 4th week. Corresponding to these sites, Prussian blue staining consistently showed that large clusters of cells were labeled by dense intracellular iron at the scar tissue. Conclusion Feridex labeling BM-MNCs enables ready detection in the beating heart on a conventional MR scanner after transplantation into canine infarcted myocardium.

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