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Abstract This study compared the pH and calcium ion release of calcium silicate- (Bio-C Temp) and calcium hydroxide-based (Ultracal XS) medications. Intracanal remnants of both medications were also evaluated using SEM-EDS after the removal protocol. Thirty-five bovine teeth were prepared. Fifteen were filled with Bio-C Temp and 15 with Ultracal XS. Five remained without intracanal medication (control group). Five samples from each experimental time (i.e.. 24, 72, and 168 hours) were used to measure pH and calcium ions release using a digital pH meter and microplate reader, respectively. Afterward, the peaks of the chemical elements composing both medications were analyzed in SEM-EDS. One-way ANOVA and Tukey's post hoc test analyzed the pH and calcium ion release data. Student's t-test compared the medications in each experimental time. SEM-EDS described the percentage of chemical elements in the samples. Bio-C Temp and Ultracal XS showed a significant pH increase from 24 to 168 hours (p<0.05). Ultracal XS showed a higher pH value at 24 hours than Bio-C Temp (p<0.05) but were similar at 72 and 168h (p > 0.05). Calcium ion release did not depend on the experimental period (p > 0.05). Bio-C Temp showed lower calcium ions release than Ultracal XS at 24 hours (p<0.05). SEM-EDS analyses showed the remains of both medications, but the concentration of Si, Al, and W ions was present only in the calcium silicate-based medication. Bio-C Temp presented alkaline pH and a satisfactory calcium ion release over the time. The remaining of both medications were present after the protocols for paste removal.
Resumo Este estudo comparou o pH e a liberação de íons cálcio de medicações intracanais a à base de silicato de cálcio (Bio-C Temp) e à base de hidróxido de cálcio (Ultracal XS). Remanescentes de ambas as medicações também foram avaliados usando microscopia eletrônica de varredura e espectroscopia de dispersão de energia após o protocolo de remoção. Trinta e cinco dentes bovinos foram preparados. Quinze dentes foram preenchidos com Bio-C Temp e 15 com Ultracal XS. Cinco permaneceram sem medicação intracanal (grupo controle). Cinco amostras de cada tempo experimental (ou seja, 24, 72 e 168 horas) foram usadas para medir o pH e a liberação de íons de cálcio usando um medidor de pH digital e um leitor de microplacas, respectivamente. Em seguida, os picos dos elementos químicos que compõem os dois medicamentos foram analisados em microscopia eletrônica de varredura e por espectroscopia de dispersão de energia. Os testes One-way ANOVA e post hoc de Tukey analisaram os dados de pH e liberação de íons cálcio. O teste t de Student comparou as medicações em cada tempo experimental. A microscopia eletrônica de varredura e a espectroscopia de dispersão de energia descreveu a porcentagem de elementos químicos nas amostras. O Bio-C Temp e o Ultracal XS mostraram um aumento significativo de pH de 24 a 168 horas (p<0,05). O Ultracal XS apresentou um valor de pH mais alto em 24 horas do que o Bio-C Temp (p<0,05), mas foi semelhante em 72 e 168h (p > 0,05). A liberação de íons cálcio não dependeu do período experimental (p> 0,05). O Bio-C Temp apresentou menor liberação de íons de cálcio do que Ultracal XS em 24 horas (p<0,05). As análises de microscopia eletrônica de varredura e espectroscopia de dispersão de energia mostraram remanescentes de ambas as medicações, mas a concentração de íons Si, Al e W estavam presentes apenas na medicação à base de silicato de cálcio. O Bio-C Temp apresentou pH alcalino e maior liberação de íons cálcio. Remanescentes de ambas as medicações estiveram presentes após os protocolos de remoção da pasta.
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OBJECTIVE@#To explore the mechanism by which inositol-requiring enzyme-1α (IRE1α) regulates autophagy function of chondrocytes through calcium homeostasis endoplasmic reticulum protein (CHERP).@*METHODS@#Cultured human chondrocytes (C28/I2 cells) were treated with tunicamycin, 4μ8c, rapamycin, or both 4μ8c and rapamycin, and the expressions of endoplasmic reticulum (ER) stress- and autophagy-related proteins were detected with Western blotting. Primary chondrocytes from ERN1 knockout (ERN1 CKO) mice and wild-type mice were examined for ATG5 and ATG7 mRNA expressions, IRE1α and p-IRE1α protein expressions, and intracellular calcium ion content using qPCR, Western blotting and flow cytometry. The effect of bafilomycin A1 treatment on LC3 Ⅱ/LC3 Ⅰ ratio in the isolated chondrocytes was assessed with Western blotting. Changes in autophagic flux of the chondrocytes in response to rapamycin treatment were detected using autophagy dual fluorescent virus. The changes in autophagy level in C28/I2 cells overexpressing CHERP and IRE1α were detected using immunofluorescence assay.@*RESULTS@#Tunicamycin treatment significantly up-regulated ER stress-related proteins and LC3 Ⅱ/LC3 Ⅰ ratio and down-regulated the expression of p62 in C28/I2 cells (P < 0.05). Rapamycin obviously up-regulated LC3 Ⅱ/LC3 Ⅰ ratio (P < 0.001) in C28/I2 cells, but this effect was significantly attenuated by co-treatment with 4μ8c (P < 0.05). Compared with the cells from the wild-type mice, the primary chondrocytes from ERN1 knockout mice showed significantly down-regulated mRNA levels of ERN1 (P < 0.01), ATG5 (P < 0.001) and ATG7 (P < 0.001), lowered or even lost expressions of IRE1α and p-IRE1α proteins (PP < 0.01), and increased expression of CHERP (P < 0.05) and intracellular calcium ion content (P < 0.001). Bafilomycin A1 treatment obviously increased LC3 Ⅱ/ LC3 Ⅰ ratio in the chondrocytes from both wild-type and ERN1 knockout mice (P < 0.01 or 0.05), but the increment was more obvious in the wild-type chondrocytes (P < 0.05). Treatment with autophagy dual-fluorescence virus resulted in a significantly greater fluorescence intensity of LC3-GFP in rapamycin-treated ERN1 CKO chondrocytes than in wild-type chondrocytes (P < 0.05). In C28/I2 cells, overexpression of CHERP obviously decreased the fluorescence intensity of LC3, and overexpression of IRE1α enhanced the fluorescence intensity and partially rescued the fluorescence reduction of LC3 caused by CHERP.@*CONCLUSION@#IRE1α deficiency impairs autophagy in chondrocytes by upregulating CHERP and increasing intracellular calcium ion content.
Subject(s)
Animals , Mice , Autophagy , Calcium/metabolism , Chondrocytes , Endoplasmic Reticulum/metabolism , Endoribonucleases/pharmacology , Homeostasis , Inositol , Mice, Knockout , Protein Serine-Threonine Kinases , RNA, Messenger/metabolism , Sirolimus/pharmacology , Tunicamycin/pharmacologyABSTRACT
Objective: To compare the antidiarrheal effects of Mongolian medicine, Holarrhena antidysenterica, Forsythia suspensa and Cynanchum thesioides on diarrhea model rats and investigate its effects on serum DAO (diamine oxidase), cAMP (cyclic adenosine phosphate), TNF-α (tumor necrosis factor-α), ATPase and calcium ions. Methods: The normal control group, model group, H. antidysenterica low-dose and high-dose groups, F. suspensa low dose and high-dose groups, C. thesioides low dose and high dose groups were set. Except the normal control group, the other groups were ig administrated water decoction of Cassia angustifolia to establish diarrhea model; After the success of the model, the rats in treatment groups were administrated by gastric drug for 7 d, the type mental state, diarrhea and body weight changes were observed. the abdominal aortic blood was obtained at the last day of fasting 12 h after the administration. DAO, cAMP, TNF-α, ATP enzyme, OD value of the calcium ions in serum were determined by using ELISA (enzyme-linked immune detection reagent) kits. Results: General status: except for the normal group, the mental state of the rats in the other groups was depressed after modeling, the fur color of them was significantly decreased and the body weight was decreased. The diarrhea rate was 100% on the 4th day after modeling. Compared with the model group, there were significant differences in the number of loose stools, grade of loose stools and diarrhea index (P < 0.05, 0.01) in each administration group. The serum DAO, TNF-α, ATPase, cAMP and calcium ion OD values were compared: the serum concentrations of DAO in H. antidysenterica low dose group, C. thesioides low dose group and F. suspensa high and low dose groups of rats were significantly lower than model group with significant differences (P < 0.05), and were significantly higher than normal group. The serum concentration of TNF-α in C. thesioides high and low dose groups were lower compared with model group (P < 0.05). The serum ATPase in C. thesioides high and low dose groups had significant difference (P < 0.05) compared with model group. The serum concentration of cAMP in H. antidysenterica high-dose group and F. suspensa low-dose group was significantly lower compared with model group with significant differences (P < 0.05). Serum Ca2+ concentration in the drug administration groups was significantly different from that in the model group (P < 0.05). Conclusion: The antidiarrheal effect of C. thesioides is better than that of H. antidysenterica and F. suspensa.
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Objective: To prepare pH-sensitive drug releasing As2O3 loaded liposome (CaAs-LP) and evaluate it in vitro. Methods: CaAs-LP was prepared by thin film dispersion and ion precipitation method. The particle size, PDI, and Zeta potential of CaAs-LP were measured by Malvern particle size analyzer; The morphology of the liposome was investigated by transmission electron microscopy; The drug loading and entrapment efficiency of CaAs-LP by inductively coupled plasma emission spectrum. In vitro release characteristics of CaAs-LP under different pH conditions were investigated by dialysis bag method. MTT assay was used to investigate the toxicity of carrier and CaAs-LP to MCF-7, U87 and HepG2 cells. Results: The prepared CaAs-LP were spherical and well-dispersed with particle size of (117.16 ± 1.94) nm. The encapsulation efficiency and the drug loading rate of CaAs-LP were (74.31 ± 2.11)% and (8.31 ± 0.13)%, respectively. In vitro release studies showed that CaAs-LP had the characteristics of sustained release and pH sensitive drug release, which can achieve specific drug release in the tumor environment. The carrier displayed remarkable biocompatibility in MCF-7, U87, HepG2 and L02 cells. MTT assay showed that the median lethal concentrations (IC50 values) of MCF-7, U87 and HepG2 cells were 11.91, 4.90 and 19.41 μmol/L, while L02 was 27.59 μmol/L, respectively, which showed strong inhibiting effect on tumor cells. Conclusion: CaAs-LP reveals significantly sustained and pH sensitive release characteristics. CaAs-LP is a potential drug delivery system against solid tumor with tumor micro-environment responsive.
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Background: Hypocalcemia is one of the important complications of diabetes mellitus. It occurs when the patient develops renal insufficiency but hypercalcemia occurs in diabetes due to many mechanisms including insulin resistance. Meanwhile, hypercalcemia itself produces insulin resistance and the calcium is the important one for the production of insulin and glucose uptake in the cells. Aim of the study: To assess left ventricular dimension and wall thickness mass in diabetic patients having high serum calcium level. Materials and methods: This study was conducted in Government Royapettah Hospital, Chennai for duration of 6 months from April 2018 to September 2018. 2016 patients were enrolled in the study. After obtaining an informed written consent, demographic details, past medical history and clinical examination was done. Following investigation was done in all patients. Serum calcium, serum creatinine, total cholesterol, triglycerides, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), fasting blood glucose was done. 2D ECHO – echocardiography was done in all patients. In left lateral position ECHO was performed in parasternal long axis, 4 chamber view. M mode was used to assess the septal wall, posterior wall thickness and left ventricular diastolic dimension. By using wall thickness left ventricular mass is calculated. Results: According to our serum calcium was main Determinator of left ventricular remodeling by many mechanisms. Serum calcium was > 10.2 in LVH group people but in non-LVH group people serum calcium level was within the normal limit that was given as < 10.2 mg/dl. 1 patient in non-LVH group was having high serum calcium but does not make statistical changes in that group. The mean serum calcium of LVH group was 10.6mg/dl. D. Venkateswarlu, M. Praveen Kumar. A study of high serum calcium level in diabetes mellitus and its association with left ventricular remodeling. IAIM, 2019; 6(9): 66-71. Page 67 Conclusion: Normal calcium mandatory for excitation-contraction coupling but high calcium adversely affect the ECC and produces ventricular dysfunction and through neurohormonal mechanism it produces cardiac muscle hypertrophy. According to this study increased serum calcium in diabetes has strong correlation with occurrence of cardiac remodeling.
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AIM:To observe the effects and mechanisms of hydroxyethylstarch (HES) 130/0.4 on no-reflow phenomenon after myocardial ischemia-reperfusion in rats.METHODS: SD rats were randomly divided into 4 groups:sham operation group , ischemia-reperfusion ( IR, treated with normal saline ) group, normal saline ischemia-reperfusion (NS-IR, treated with NS) group and HES ischemia-reperfusion (HES-IR, treated with HES) group.Myocardial infarct size and no-reflow range were determined by staining methods , and the activities of myocardial enzymes ( CK-MB, cTnI and MPO) were measured .Meanwhile , cardiac microvascular endothelial cells of the rat were cultured and divided into 4 groups:control group, hypoxia/reoxygenation (H/R) group, NS-H/R group and HES-H/R group.Acute ischemia reper-fusion models were simulated , and the concentration of calcium ions was measured .The relative cell activity was evaluated by CCK-8 assay, and the apoptotic rate was detected by flow cytometry .RESULTS:In HES-IR group, the myocardial in-farct size, the no-reflow zone, CK-MB, cTnI and MPO activity were all significantly lower than those in IR group ( P<0.05).In microvascular endothelial cells , the concentration of calcium ions and the apoptotic rate in HES-H/R group were significantly decreased, while the relative cell activity increased compared with H/R group (P<0.05).CONCLUSION:HES reduces no-reflow in acute myocardial ischemia-reperfusion .The mechanism may be involved in the inhibition of both the infiltration of neutrophils and the calcium overload of endothelial cells .
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La determinación de Dureza Total con EDTA en agua usando una solución amortiguadora de amonio pH 10 tiene la desventaja de generar vapores de gas amoníaco que suelen ser molestos o ser potencialmente dañinos para el sistema respiratorio del operario. El objetivo de este estudio fue utilizar una solución amortiguadora inodora de borato pH 10 en sustitución de una solución amortiguadora de amonio a pH 10 para la determinación de la dureza total en agua por la metodología de la norma COVENIN 2408-86 y determinar si existía diferencia estadísticamente significativa entre ambos procedimientos. Se determinó la Dureza Total usando la solución amortiguadora inodora de borato en 13 muestras de agua con diferentes grados de dureza (suave, dura y muy dura); los resultados obtenidos se compararon con los valores del procedimiento de referencia. La solución amortiguadora permitió una visualización rápida y definida del punto final durante la ejecución de la determinación volumétrica, los resultados mostraron que no existe diferencia estadísticamente significativa (p≤0,05) en los valores de dureza al emplear ambas soluciones amortiguadoras. Se concluyó que el empleo de la solución amortiguadora inodora de borato para la cuantificación de dureza total en agua es una alternativa a la solución amortiguadora de amonio.
Total Hardness determination EDTA in water using ammonium buffer solution pH 10 has the disadvantage of generating ammonia gas vapors are usually upset or be potentially harmful to the respiratory system operator. The aim of this study was to use a buffer solution pH 10 borate odorless replacing ammonium buffer solution at pH 10 for the determination of total water hardness in the methodology of COVENIN 2408-86 standard and determine whether there was difference statistically significant between the two procedures. Total Hardness was determined using borate buffer odorless in 13 water samples with different degrees of hardness (soft, hard and very hard); the results obtained were compared with the reference method values. The buffer allowed rapid and sharp display of the end point during the execution of the volumetric determination, the results showed that there was no statistically significant difference (p≤ 0,05) in hardness values by using two buffers. It was concluded that the use of borate buffer odorless for quantification of total hardness water is an alternative to the ammonium buffer.
Subject(s)
Humans , Male , Female , Water Quality/standards , Borates/pharmacology , Water Hardness/analysis , Calcium , Public Health , MagnesiumABSTRACT
We investigated the polyelectrolyte properties of actin filaments which are in interaction with myosin motors, basic participants in mechano-electrical transduction in the stereocilia of the inner ear. Here, we elaborated a model in which actin filaments play the role of guides or pathways for localized flow of calcium ions. It is well recognized that calcium ions are implicated in tuning of actin-myosin cross-bridge interaction, which controls the mechanical property of hair bundle. Actin filaments enable much more efficient delivery of calcium ions and faster mechanism for their distribution within the stereocilia. With this model we were able to semiquantitatively explain experimental evidences regarding the way of how calcium ions tune the mechanosensitivity of hair cells.
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Objective As the photostability of calcium ions (Ca2+) indicators is an important property for indicating the temporal features of cytosolic Ca2+ in cells, this study aims to quantitatively measure the light-induced fluorescence enhancement in cells stained with Ca2+ indicators. Methods Five cell lines, MC3T3-E1, RAW264.7, MLO-Y4, MEF3T3 and HEK293, were exposed to the light with five levels of optical power, respectively, so as to investigate the light induced responses of two commonly-used Ca2+ indicators, Fluo-4 AM and Oregon green. The light-induced fluorescence enhancement, the succeeding photobleaching and the thapsigargin (TG)-induced responsive peak followed by were observed. The characteristic parameters of responsive peaks were further analyzed. Results Light with higher power level would induce the fluorescence enhancement for both Fluo-4 AM or Oregon green, while the responsive percentage as well as the magnitude and time span of light-induced peak of Oregon green-stained cells were significantly lower than those of Fluo-4 AM-stained cells. Conclusions The use of Oregon green with low power level light shows better photostability to indicate the intracellular Ca2+.
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Objetivo: Avaliar o pH e liberação de íons cálcio dos materiais forradores a base de hidróxido de cálcio não fotopolimerizável (Hydro C), um fotopolimerizável (Biocal) e MTA. Os materiais foram manipulados e inseridos em tubos de 1 cm de comprimento e 1 mm de diâmetro. Os tubos foram preenchidos e imediatamente imersos em frascos contendo 10 mL de água deionizada. Os tubos foram removidos dos frascos depois de 10 minutos, 24, 48 horas, 7, 15 e 30 dias, e a liberação de íons cálcio e hidroxila foi mensurada com um pHmetro e espectrofotômetro de absorção atômica, respectivamente. Os dados foram comparados pela análise de variância a dois critérios, e as comparações individuais pelo teste de Tukey-Kramer, com nível de significância de 5%. Com relação a liberação de íons calcio, no periodo de 10 minutos ocorreram diferenças significantes (P<0,05) nas comparações do MTA com os outros dois materiais. Nos períodos de 24 e 48 horas os três materiais se diferenciaram estatisticamente (P<0,05) entre si. Na análise de 7 e 15 dias ocorreram diferenças significantes (P<0,05) nas comparações entre: MTA e Biocal, e no confronto entre Hydro C e Biocal. Na avaliação de 30 dias as diferenças significantes (P<0,05) ocorreram nas comparações do MTA com os demais materiais. Com relação ao pH, no período de 10 minutos e 24 horas não ocorreram diferenças significantes (P>0,05). Nos períodos de 48 horas ocorreu diferença estatística (P<0,05) nas comparações do BioCal com os outros dois materiais. Na análise de 7 dias ocorreu diferença significante (P<0,05) na comparação entre MTA e Biocal. Na avaliação de 15 dias ocorreram diferenças significantes (P<0,05) na comparação do Hidro C com os demais materiais. Na análise de 30 dias ocorreram diferenças significantes (P>0,05) nas comparações. Conclui-se que todos os materiais foram capazes de liberar íons cálcio e hidroxila.
Objective: Evaluate the pH and calcium ion release from the pulp-capping materials based on calcium hydroxide does not light-cured (Hydro), a light-cured (Biocal) and MTA. The materials were manipulated and inserted into tubes of 1 cm in length and 1 mm in diameter. The tubes were completed and immediately immersed in vials containing 10 mL of deionized water. The tubes were removed from bottles after 10 minutes, 24, 48 hours, 7, 15 and 30 days, and calcium and hydroxyl ions release was measured with an atomic absorption spectrophotometer and pHmetro, respectively. The data were compared by analysis of variance on two criteria, and individual comparisons by Tukey-Kramer test with significance of 5%. Regarding the calcium ion release, in period of 10 minutes there were significant differences (P<0 .05) MTA comparisons with the other two materials. During periods of 24 and 48 hours the three materials have differentiated statistically (P<0 .05) among themselves. Analysis of 7 and 15 days there were significant differences (P<0 .05) in the comparisons between: MTA and the confrontation between Biocal and Hydro C and Biocal. 30 days evaluation of significant differences (P<0 .05) occurred in MTA comparisons with other materials. With regards to pH, within 10 minutes and 12:0 am not significant differences occurred (P>0 .05). During periods of 48 hours there was statistical difference (P0 .05) in BioCal's comparisons with the other two materials. In During periods of 48 hours there was statistical difference (P<0 .05) in BioCal's comparisons with the other two materials. Analysis of 7 days there was significant difference (P<0 .05) in the comparison between MTA and Biocal. In 15 days trial significant differences occurred (P<0 .05) in comparison with the other's Hydro C materials. In the analysis of significant differences occurred 30 days (P<0 .05) in the comparisons. It is concluded that all materials were able to release calcium ions and hydroxyl.
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Objective To study the effect and mechanism of tetrandrine (Tet) treatment of severe acute pancreatitis (SAP). Methods 45 SD rats were randomly divided into 3 groups: control group, severe acute pancreatitis group (SAP group) and tetrandrine group (Tet group). 5 rats were randomly taken from each group 3, 6, and 12 h after operation, and then underwent laparotomy for testing. Detection targets included calciumion concentration, pancreatic acinar calcium fluorescence intensity and pancreas pathological evaluation. Results In terms of the value of all detection targets, there was no statistical difference for the control group between different time points (P ＞0.05 )while there was statistical difference for SAP group and TET group in different time points (P＜0.05). Conclusion The experiment confirms that Tet, as a calcium blocker, can inhibit calcium to penetrate into pancreatic acinar cells, thus effectively reduce the pathological damage to pancreas of the experimental rats. Calcium overload plays an important role in SAP development.
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OBJETIVO: O objetivo deste estudo foi avaliar o pH e difusão de íons cálcio da pasta de hidróxidode cálcio e propilenoglicol, a partir de três marcas comerciais. Foram utilizados quatro grupos, cada umcom dez dentes humanos (G1=Inodon®, G2=Biodinâmica®, G3=Farmadoctor, G4=controle).MATERIAL E MÉTODO: Os dentes foram preparados e os grupos 1, 2 e 3 preenchidos com asrespectivas pastas; o grupo controle sem pasta. A análise do pH foi feita por medidor de pH e amedição da difusão dos íons cálcio pelo método colorimétrico, com tempos de 0 e 48 horas, 7, 14, 21e 28 dias. A análise estatística foi realizada utilizando os testes ANOVA a dois critérios com medidasrepetidas, modelo fatorial completo, comparações múltiplas de Tukey HSD, teste de normalidade deKolmogorov-Smirnov, coeficiente de correlação de Pearson. O nível de significância foi de 5% com ouso do software SPSS 15.0. RESULTADOS: Os resultados mostraram que, independentemente dostempos analisados, para a média dos valores do pH houve diferença estatística entre os grupos (P<0,05),sendo que o grupo controle apresentou a menor média de pH diferindo dos outros três. Na difusão deíons cálcio observou-se diferenças significativas na média do G4 e demais grupos (p<0.05). Em 48horas a maior média ocorreu no grupo G1, em 7, 14 e 21 dias no G2 e em 28 dias no G1.CONCLUSÕES: Não houve diferença no pH dos grupos experimentais; a difusão de íons de cálciofoi maior no G1 e G2, com tendência crescente somente no G1.
OBJECTIVE: The purpose of this study was to evaluate the pH and dissemination of calciumions in the folder of calcium hydroxide and propylene from three trademarks (Inodon, Biodinâmicaand Farmadoctor). Four groups of specimens were used, each containing ten human teeth (GI Inodon; G2 Biodinâmica; G3 Farmadoctor; G4 - control). The teeth were prepared and groups1, 2 and 3 satisfied with their portfolios and the control group without portfolio. pH was measuredby a pH meter and the diffusion of calcium ions was measured by the colorimetric method (0 and48 hours, 7, 14, 21 and 28 days). The statistical analysis was performed using the tests on twocriteria ANOVA with repeated measures, full factorial design, multiple comparisons of TukeysHSD, test of normality of Kolmogorov-Smirnov, Pearsons correlation coefficient. The level ofsignificance was 5% with the use of the software SPSS 15.0. RESULTS: The results showedthat, regardless of time tested, for the average values of pH was no statistical difference betweenthe groups (P <0.05), while the control group had the lowest average Ph. In the disseminationof calcium ions there was significant differences in average for the G4 and other groups (P<0.05). In 48 hours at higher average occurred in the group G1, 7, 14 and 21 days in G2 and28 days in G1. CONCLUSION: There was no difference in the pH of experimental groups, thediffusion of ions of calcium was higher in G1 and G2, with only growing trend in G1.
Subject(s)
Humans , Calcium Hydroxide/chemistry , Calcium/chemistry , In Vitro Techniques , Analysis of Variance , Hydrogen-Ion Concentration , Pharmaceutical Vehicles/chemistry , Propylene Glycol/chemistry , Root Canal Irrigants/chemistry , Time FactorsABSTRACT
Objective To investigate the changes of retinal ganglion cells (RGCs) exposed to hypoxia and the mechanism. Methods RGCs were isolated from the retina of neonatal Long Evans rats aged 1 day and cultured, then divided into normal control group and hypoxia group (cultured in incubator containing 1 O_2, 5 CO_2 and 94 N_2). At 1, 3, 12 and 24 h after incubation, the calcium ion level by laser scanning confocal fluorescence microimaging system, the activity of SOD and the content of MDA by biochemistry technology, TNF-? by ELISA were detected. Results No changes of calcium ion level in RGCs were observed in normal control group. The calcium ion level increased significantly in the hypoxia group (P
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Aim To study the effect of Bay k8644 on cardiac function with the model of myocardial ischemia-reperfusion injury(MIRI)in Rats.Methods Rat MIRI was induced by occluding the left anterior descending coronary artery for 40 min followed by 90 min reperfusion.Eighteen rats were divided randomly into 3 groups: saline,Bay k8644 and 0.1% dimethyl sulfoxide(DMSO)intravenously injected 30 min after ischemia.Heart functions were assessed before ischemia and 5,20 and 40 min after initiation of ischemia and 5,30,60 and 90 min after reperfusion,by measuring heart rate(HR),the left ventricular systolic pressure(LVSP),left ventricular end diastolic pressure(LVEDP) and ?dp/dt_(max).Results After ischemia,LVSP and +dp/dt_(max) decreased(P
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Transglutaminase enzymes (TGases) catalyze the calcium dependent formation of an isopeptide bond between protein-bound glutamine and lysine substrates. Previously we have shown that activated TGase 3 acquires two additional calcium ions at site two and three. The calcium ion at site three results in the opening of a channel. At this site, the channel opening and closing could modulate, depending on which metal is bound. Here we propose that the front of the channel could be used by the two substrates for enzyme reaction. We propose that the glutamine substrate is directed from Trp236 into the enzyme, shown by molecular docking. Then a lysine substrate approaches the opened active site to engage Trp327, leading to formation of the isopeptide bond. Further, direct comparisons of the structures of TGase 3 with other TGases have allowed us to identify several residues that might potentially be involved in generic and specific recognition of the glutamine and lysine substrates.
Subject(s)
Animals , Humans , Binding Sites , Calcium/metabolism , Calcium-Binding Proteins/metabolism , Glutamine/metabolism , Lysine/metabolism , Models, Chemical , Models, Molecular , Protein Binding , Protein Structure, Tertiary , Transglutaminases/metabolismABSTRACT
Objective: To study the protective effect in CCl4-induced liver injury by organoselenium from Se-enriched lactobacillus. Methods: (1) In the first series, forty-five animals were randomly divided into control (C) group, CCl4 group, CCl4 plus organoselenium group (CCl4-Se group). The liver injury was induced by abdominal injection of CCl4 every other day for 4 w. Changes of GSH-Px, CAT and SOD activities as well as MDA content in liver were estimated in the 2nd and 4th week after CCl4 injection respectively. (2) In the second series, forty-eight mice were randomly divided into C group, CCl4 group, CCl4 plus low dose organoselenium group (CCl4-LSe group) and CCl4 plus high dose organoselenium group (CCl4-HSe group). Changes of hepatocyte [Ca2+]i in animals in every group were investigated by means of confocal laser microscope on the 4th and 8th day after CCl4 injection respectively. Results: During the entire experimental period, liver MDA of CCl4 group was markedly superior to that of C and CCl4-Se groups, and the level of latter two groups was very close. The GSH-Px and CAT activities were higher in CCl4-Se group than in CCl4 group,but lower than that of C group. There were higher SOD activities in C and CCl4-Se groups compared to that in CCl4 group though without obvious difference. Average fluorescence pixels of hepatocyte [Ca2+]i in CCl4 group was 2.8 and 5.5 times higher than that of group C in the 4th and 8th day respectively,while those in CCl4-Se groups were significantly lower than those of CCl4 group, and close to C group. Conclusions: Organoselenium from Se-enriched lactobacillus, can protect hepatocyte [Ca2+]i homeostasis by reducing lipid peroxidation after CCl4 exposure.