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1.
Odovtos (En línea) ; 25(2)ago. 2023.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1448744

RESUMO

To evaluate whether the WaveOne Gold and Reciproc single file instrumentation systems, are effective in reducing the microbial load of a mixed biofilm and the cleaning of apical third compared to the Twisted File Adaptive system (multiple- file system). Seventy mesial roots of the first and second molars were included and randomly divided into three experimental groups (n=20, n=10 controls). Biofilms were formed inside canals over 31 days. After instrumentation with the unique file systems, WaveOne Gold and Reciproc and the multiple file system Twisted File Adaptive, using 2.25% sodium hypochlorite as an irrigant in all cases, a count of colony forming units was performed using serial dilutions, cleaning of the apical third was evaluated using scanning electron microscopy. Comparisons amongst groups were made by using parametric and non-parametric statistics, according to a normal or non-normal data distribution, respectively. No significant differences in the reduction of the microbial load after employing a single-file system in comparison to the multiple-file system were found; in addition, the cleaning of the apical third was similar for the three different instrumentation systems. The single-file system is equal in effectiveness compared with the multiple-file system in reducing the microbial load.


Evaluar si los sistemas de instrumentación de lima única, como WaveOne Gold y Reciproc son efectivos para reducir la carga microbiana de un biofilm mixto y la limpieza del tercio apical, comparado con los sistemas de limas múltiples, como Twisted File Adaptive. Setenta raíces mesiales de primeros y segundos molares fueron incluidos y divididos de forma aleatoria en tres grupos experimentales (n=20, n=10 controles). El biofilm fue formado en el interior de los conductos durante 31 días. Después se instrumentó con los sistemas de lima única (WaveOne Gold y Reciproc) y el sistema de limas múltiples Twisted File Adaptive, usando hipoclorito de sodio al 2.5% en todos los casos. El conteo de unidades formadoras de colonias se realizó usando diluciones seriales, la limpieza del tercio apical se evaluó empleando el microscopio electrónico de barrido. La comparación entre grupos se realizó con pruebas paramétricas y no paramétricas, de acuerdo con la distribución normal y no normal de los datos, respectivamente. No hubo una diferencia significativa en la reducción de la carga microbiana después de emplear los sistemas de lima única en comparación a los de limas múltiples, además, la limpieza del tercio apical fue similar en los 3 diferentes sistemas de instrumentación. Los sistemas de lima única son igual de efectivos para reducir la carga microbiana comparados con los sistemas de limas múltiples.

2.
Journal of Zhejiang University. Science. B ; (12): 123-135, 2021.
Artigo em Inglês | WPRIM | ID: wpr-880714

RESUMO

Ischemic stroke presents a leading cause of mortality and morbidity worldwide. Theaflavic acid (TFA) is a theaflavin isolated from black tea that exerts a potentially neuro-protective effect. However, the dynamic properties of TFA-mediated protection remain largely unknown. In the current study, we evaluated the function of TFA in the mitochondria apoptotic pathway using mathematical modeling. We found that TFA-enhanced B-cell lymphoma 2 (Bcl-2) overexpression can theoretically give rise to bistability. The bistability is highly robust against parametric stochasticity while also conferring considerable variability in survival threshold. Stochastic simulations faithfully match the TFA dose response pattern seen in experimental studies. In addition, we identified a dose- and time-dependent synergy between TFA and nimodipine, a clinically used neuro-protective drug. This synergistic effect was enhanced by bistability independent of temporal factors. Precise application of pulsed doses of TFA can also promote survival compared with sustained TFA treatment. These data collectively demonstrate that TFA treatment can give rise to bistability and that synergy between TFA and nimodipine may offer a promising strategy for developing therapeutic neuro-protection against ischemic stroke.

3.
Rev. mex. ing. bioméd ; 39(1): 41-51, ene.-abr. 2018. graf
Artigo em Inglês | LILACS | ID: biblio-902382

RESUMO

Abstract: Among the most common problems within dental professionals, is the fracture of rotary instruments of nickel and titanium root canal files (NiTi), when performing a procedure on a patient. Therefore, the objective of this work is to compare the in vitro resistance to cyclic fatigue of K3XF and TFA rotatory instruments, in continuous rotation and adaptive motion. For this, a static and cyclic fracture test was used and a fracture pattern was searched. The numbers of cycles until the fracture and the length of the fragments were determined. Of all the groups evaluated, K3XF-A exhibited the best resistance to cyclic fatigue. In future research, it will be performed an autoclaving and immersion cycles in sodium hypochlorite to be able to determine the separation causes of the rotary instruments. As a recommendation, the operator could significantly influence the decrease in resistance to cyclic fatigue due to the misuse of rotary instruments.


Resumen: Entre los problemas más comunes entre los profesionistas dentales, es la fractura de los instrumentos rotatorios de limas de canales radiculares de níquel y titanio (NiTi), cuando se lleva a cabo el procedimiento al paciente. Es por eso, que el objetivo de este trabajo es el comparar la resistencia in vitro de la fractura cíclica entre los instrumentos rotatorios K3XF y TFA, en rotación continua y movimiento adaptativo. Para esto, se utilizó la prueba de fractura cíclica y estática y el patrón de fractura fue evaluado. El número de ciclos hasta la fractura y la longitud de los fragmentos fue determinado. De todos los grupos evaluados, K3XF-A presentó la mejor resistencia a la fractura cíclica. Como trabajo a futuro, se utilizará ciclos de inmersión en hipoclorito de sodio y autoclaveado, para ser capaces de determinar las causas de separación de los instrumentos rotarios. Como recomendación, el operador puede influenciar significativamente la disminución de la resistencia a la fractura cíclica utilizando de una manera errónea el dispositivo.

4.
Malaysian Journal of Nutrition ; : 87-98, 2013.
Artigo em Inglês | WPRIM | ID: wpr-628674

RESUMO

Introduction: There is a lack of information on the trans fatty acid (TFA) content in Malaysian foods. The objective of this study is to determine the TFA content of bakery products, snacks, dairy products, fast foods, cooking oils and semisolid fats, and breakfast cereals and Malaysian fast foods. This study also estimated the quantity of each isomer in the foods assayed. Methods: The trans fatty acid content of each food sample was assessed in duplicate by separating the fatty acid methyl esters (FAME) in a gas chromatography system equipped with HP- 88 column (USA: split ratio 10: 1) for cis/trans separation. Five major TFA isomers, palmitoelaidic acid (16: 1t9), petroselaidic acid (18:1t6), elaidic acid (18:1t9), vaccenic acid (18: 1t11) and linoelaidic acid (18:2t9, 12), were measured using gas chromatography (GC) and the data were expressed in unit values of g/100 g lipid or g/100 g food. Results: The total TFA contents in the studied foods were <0.001 g-8.77 g/100 g lipid or <0.001 g-5.79 g/100 g foods. This value falls within the standard and international recommendation level for TFA. The measured range of specific TFA isomers were as follows: palmitoelaidic acid (<0.001 g-0.26 g/100 g lipid), petroselaidic acid (<0.001 g – 3.09 g/100 g lipid), elaidic acid (<0.001 g-0.87 g/100 g lipid), vaccenic acid (<0.001 g-0.41 g/100 g lipid) and linoelaidic acid (<0.001 g-6.60 g/100 g lipid). Conclusion: These data indicate that most of the tested foods have low TFA contents (<1 g/100 g lipid).

5.
An. venez. nutr ; 24(2): 78-85, dic. 2011. tab
Artigo em Espanhol | LILACS, LIVECS | ID: lil-705417

RESUMO

El objetivo de esta investigación fue estudiar la composición de los ácidos grasos y posible presencia de trans (AGT) en galletas y mezclas para tortas de diferentes clasificaciones de mayor consumo en Venezuela. Se realizó el análisis proximal de cada producto alimenticio cumpliendo estos con las normas COVENIN y A.O.A.C. La identificación y cuantificación de los ácidos grasos presentes se realizó por cromatografía gaseosa (CG), previa metilación. Los principales ácidos grasos presentes en las galletas fueron laúrico (C12:0), mirístico (C14:0), palmítico (C16:0), esteárico (C18:0), oleico (C18:1Δ9c), linoleico (C18:2Δ9c,12c), linolénico (C18:3Δ9c,12c,15c) y Araquidico (C20:0), al igual que mostraron la presencia de los AGT elaídico (C18:1Δ9t), y ácido graso linolelaidico (C18:2Δ9t,12c) aunque este último solo en algunos productos. Se obtuvieron entre 42-63% en ácidos grasos saturados (AGS), 30-42% en ácidos grasos monoinsaturados AGMI), 6-17% para ácidos grasos poliinsaturados (AGPI) y entre 0,11-2% de AGT en las galletas, y en las mezclas para tortas entre 32-83% de AGS, 6-24% de AGMI, 8-43% AGPI, y 1,5-2% en AGT; con variaciones de acuerdo a la matriz y tipo de producto. Se concluye que los productos alimenticios estudiados presentan el mayor contenido de ácidos grasos en saturados, y el menor en AGT, considerándose "cero trans" de acuerdo a MERCOSUR; contribuyendo así en la creación de una base de datos nacional sobre la composición de ácidos grasos en estos productos(AU)


The objective of this research was to study the fatty acid composition and presence of trans (TFA) in cookies and cake mixes of different classifications of high consumption in Venezuela. Proximate analysis was performed for each food product compliance with standards COVENIN and AOAC. The identification and quantification of the fatty acids was performed by gas chromatography (GC) after methylation. The main fatty acids present in the cookies were: lauric (C12:0), myristic (C14:0), palmitic (C16:0), stearic (C18:0), oleic(C18: 1Δ9c), linoleic (C18: 2Δ9c, 12c), linolenic (C18: 3Δ9c,12c,15c) and arachidic (C20:0), as showed the presence of TFA elaidic (C18: 1Δ9t), linolelaidic fatty acid (C18: 2Δ9t,12c) although this last only for some products. Were obtained between 42-63% saturated fatty acids (SFA), 30-42%monounsaturated fatty acids MUFA), 6-17% for polyunsaturated fatty acids (PUFAs) and from 0.1 to 2% of TFA in biscuits , and cake mixes between 32-83% AGS, 6-24% of MUFA, 8-43% PUFA, and 1.5-2% in TFA, with variations according to the matrix and product type. It is concluded that food products studied showed the highest content of saturated fatty acids, and the lowest in AGT,considered "zero trans" according to MERCOSUR, thus contributing to the creation of a national database on the composition of fatty acids in these products(AU)


Assuntos
Humanos , Masculino , Feminino , Ácidos Graxos trans , Biscoitos , Ácidos Graxos , Manipulação de Alimentos , Tecnologia de Alimentos , Doenças Cardiovasculares , Dieta , Alimentos, Dieta e Nutrição , HDL-Colesterol , LDL-Colesterol , Obesidade
6.
Chinese Journal of Radiological Medicine and Protection ; (12): 282-285, 2011.
Artigo em Chinês | WPRIM | ID: wpr-416574

RESUMO

Objective To investigate the different radioprotective effects of total flavonoids of Astragalus (TFA) on human normal mesenchymal stem cells(hMSCs) and hepatoma cells injured by 60 Coγ-ray radiation.Methods hMSCs and HepG-2 cells were cultured and randomly divided into TFA-treated and untreated groups.The cells of different groups were irradiated with 60 Co γ-rays at the dose of 6 Gy.MTT method was utilized to detect the survival rates of the hMSCs and HepG-2 cells pretreated or untreated with TFA before irradiation.Cell clone formation test was used to measure the cellular radiosensitivity.The apoptosis rates of different groups were determined by flow cytometer assay.The expression rates of the apoptosis-promoting proteins Fas and Bax and the apoptosis-inhibiting protein Bcl-2 were analyzed by Western blotting.Results MTT showed that the survival rates of hMSCs pretreated by TFA were 1.15-1.95 times higher than that of the pure irradiation group.On the contrary,the survival rates of the TFA pretreated HepG-2 cells were only 0.53-0.23 times that of the pure irradiation group.There was a good dose-effect relationship between the cell survival rate and the TFA concentration.Cell clone formation rate indicated that combined treatment of TFA and radiation inhibited the cell proliferation more effectively than single TFA or pure radiation.Flow cytometry showed that 6,24 and,48 h post-irradiation to 6 Gy,the apoptosis rates of the hMSCs were 23.3% ,11.2% ,and 2.9% ,respectively in the TFA pretreated group and were 29.3% ,24.9% ,and 13.6% in the pure radiation group.However,the apoptosis rates of the HepG-2 cells at 6,24,and 48 h post-irradiation to 6 Gy were 11.6% ,17.3% ,and 20.1% ,respectively in the TFA pretreated group and were 6.9% ,9.3% ,and 15.8% ,respectively in the direct radiation group.Western blotting showed that the expression levels of Fas and Bax proteins in the HepG-2 cells were significantly higher in the TFA pretreated group than in the pure radiation group.On the contrary,the expression level of the apoptosis inhibiting protein Bcl-2 was significantly lower in the TFA pretreated group than in the pure radiation group.Conclusions TFA has obvious effects of radiological protection on human hMSCs and has no effects of radiological protection but effects of apoptosis enhancement on hepatoma cells.The promotion of apoptosis of TFA on hepatoma cells is primarily through increasing the expression of apoptotic proteins such as Fas and Bax and reducing the expression of anti-apoptotic protein Bcl-2.

7.
China Pharmacy ; (12)1991.
Artigo em Chinês | WPRIM | ID: wpr-524124

RESUMO

OBJECTIVE:To observe the protective effect of total flavone of Abelmoschl Manihot L medic(TFA)on acute myocardial ischemic and anoxic injury in mice.METHODS:Acute myocardial ischemic model induced by subcutaneous injection of Isoproterenol was adopted to observe the effects of TFA on the abnormal ST segment in lead II and T wave on ECG,my?ocardial water content(MWC)and myocardial index(MI);Moreover the effect of TFA on myocardial anoxic tolerance was ob?served in trachea clamping mice.RESULTS:TFA could remarkably ameliorate the abnormal changes of ECG and significantly inhibit the increase of MWC and MI of model group.It was found that the ECG lasting time was much longer in the groups pretreated with TFA.CONCLUSION:TFA plays a protective role in myocardial ischemia and anoxic injury in mice.

8.
Chinese Pharmacological Bulletin ; (12)1987.
Artigo em Chinês | WPRIM | ID: wpr-557900

RESUMO

Aim To observe the protective effect and possible mechanisms of Total Flavone of Abelmoschus Manihot L medic(TFA) on myocardial reperfusion injury in rabbits,when it was given as a preconditioning inducer.Method Different doses of TFA were perfused intravenously lasting for 5 min,followed by a 10 min break before 30 min ischemia and 60 min reperfusion in rabbits.Using this preconditioning method,we observed the histo-pathological changes of myocardium,the content of MDA,the activities of SOD and GSH-PX in plasma,and also,the expression of ICAM-1 in myocardium.Results TFA(16,8 and 4 mg?kg~(-1)) significantly ameliorated myocardium ischemical reperfusion injury.The activities of SOD and GSH-PX in plasma were enhanced,while the MDA level was decreased.Meanwhile,the expression of ICAM-1 mRNA in myocardium was down-regulated.Conclusion Pharmacological preconditioning of TFA could protects myocardial ischemic reperfusion injury in rabbits by inhibiting lipid peroxidation and myocardium inflammatory reaction.

9.
Chinese Pharmacological Bulletin ; (12)1987.
Artigo em Chinês | WPRIM | ID: wpr-553602

RESUMO

AIM To observe the protective effect of total flavone of Abelmoschl Manihot L medic(TFA) on myocardial ischemia reperfusion injury(IRI) in the rat heart in vitro. METHODS We adopted the method of in vivo perfusion set up by Langendorff to observe the changes of some markers, such as MDA,SOD,CPK,LDH,etc in the myocardial homogenate in the rat heart following ischemia and reperfusion. RESULTS TFA( 100,50,25 mg?L -1) can significantly reduce the lipid peroxidation product malondialdehyde(MDA), increase the activity of myocardium superoxide dismutase(SOD), decrease the transudation of creatine phosphokinase(CPK) and lactate dehydrogenase (LDH) from cardiomyocyte. And also, TFA caused an improvement of nitric oxide (NO) and its synthase, NOS. CONCLUSION TFA play a protective role on myocardial reperfusion injury in the rat in vitro via inhibition of lipid peroxidation, enhancement of anti-oxidation and relaxing of coronary artery.

10.
Chinese Pharmacological Bulletin ; (12)1986.
Artigo em Chinês | WPRIM | ID: wpr-677459

RESUMO

AIM To study the protective and mechanism of Tfa (total flavone of the flowers of Abelmoschl Manihot L. Medic). METHODS The rats were injected Iso and then the T wave movement value observed. The rats anterior descenging bracnch of left artery were occluded for 48 hours the results of CPK, LDH and disscoate fatty acid of serum and infarct area of myocardium observed. RESULTS Tfa 100,200 mg?kg -1 ,ip depressed the T wave rise by injection of Iso in rats. Tfa 100 mg?kg -1 ?d -1 ?3,ip inhibited the serum CPK and LDH disscoate fatty acid in myocardium induced by coronary artery occluded in rats;also markedly depressed the infarct area in myocardial infarct rats. Tfa 0 03 mg?kg -1 ?d -1 ?3,ip obviously reduced the MDA contents,increased SOD and GSHPx activities in the mitochondria in mice. CONCLUSION Tfa shows a protective effect against myocardial injury. The mechanism may be via against oxygen free radicals and lipid peroxidation,also stabilize the mitochondria function.

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