Extent of ureolysis was maximum in urea control set (88%), followed by set–II (66.4%) and set–I (35.2%). Out of total DIC generated from microbial metabolism and ureolysis in set–I (277.6 mg/l) and set–II (464.9 mg/l), only about 54.1 mg/l and 180.1 mg/l was precipitated as CaCO3, whereas 189.3 mg/l and 231.3 mg/l DIC escaped into headspace, respectively. Increased time separation between ureolysis and calcification steps in set–II and higher dosage of Ca2+ resulted in synergistic improvement in DIC capture. In a reusability test, the spent supernatant from set–II could precipitate additional amount CaCO3from CO2saturated water,which was twice as much as that of the fresh media control. 相似文献
Methods: In the present study, we demonstrated that H2O2-induced apoptosis and hypertrophy of H9c2 cardiomyoblasts was markedly exacerbated by small interfering RNA (siRNA) specific for IDH2.
Results: Attenuated IDH2 expression resulted in the modulation of cellular and mitochondrial redox status, mitochondrial function, and cellular oxidative damage. MitoTEMPO, a mitochondria-targeted antioxidant, efficiently suppressed increased caspase-3 activity, increased cell size, and depletion of cellular GSH levels in IDH2 siRNA-transfected cells that were treated with H2O2.
Discussion: These results indicated that the disruption of cellular redox balance might be responsible for the enhanced H2O2-induced apoptosis and hypertrophy of cultured cardiomyocytes by the attenuated IDH2 expression. 相似文献
Materials: Robust LC and LC-MS/MS methods were established for the determination of biomarkers including 8-hydroxy-2′-deoxyguanosine, malondialdehyde, F2α-isoprostanes and hydroxylated polycyclic aromatic hydrocarbons. As a pilot study, nine volunteers travelled from Germany (mean daily concentration of PM2.5: 21?μg/m3) to China (mean daily concentration of PM2.5: 108?μg/m3). Urine samples were collected before and after the trip.
Results: In samples collected after return to Germany, the median concentrations of oxidative stress biomarkers were observed to be higher than in samples collected before leaving Germany. Decreasing trends were observed in the sequences of samples collected after return in the following weeks. Correlations were found between exposure and oxidative stress biomarkers.
Conclusion: Travellers are ideal models for PM pollution-induced acute health effects study. Exposure to PM pollution can cause oxidative stress and damage. 相似文献
Objective: To identify the extent to which TRPA1 ion channels are involved in modulating CM contractile function and elucidate the cellular mechanism of action.
Methods and Results: Freshly isolated CMs were obtained from murine heart and loaded with Fura-2 AM. Simultaneous measurement of intracellular free Ca2+ concentration ([Ca2+]i) and contractility was performed in individual CMs paced at 0.3 Hz. Our findings demonstrate that TRPA1 stimulation with AITC results in a dose-dependent increase in peak [Ca2+]i and a concomitant increase in CM fractional shortening. Further analysis revealed a dose-dependent acceleration in time to peak [Ca2+]i and velocity of shortening as well as an acceleration in [Ca2+]i decay and velocity of relengthening. These effects of TRPA1 stimulation were not observed in CMs pre-treated with the TRPA1 antagonist, HC-030031 (10 µmol/L) nor in CMs obtained from TRPA1?/? mice. Moreover, we observed no significant increase in cAMP levels or PKA activity in response to TRPA1 stimulation and the PKA inhibitor peptide (PKI 14–22; 100 nmol/L) failed to have any effect on the TRPA1-mediated increase in CM contractile function. However, TRPA1 stimulation resulted in a rapid phosphorylation of Ca2+/calmodulin-dependent kinase II (CaMKII) (1–5 min) that correlated with increases in CM [Ca2+]i and contractile function. Finally, all aspects of TRPA1-dependent increases in CM [Ca2+]i, contractile function and CaMKII phosphorylation were virtually abolished by the CaMKII inhibitors, KN-93 (10 µmol/L) and autocamtide-2-related peptide (AIP; 20 µmol/L).
Conclusions: These novel findings demonstrate that stimulation of TRPA1 ion channels in CMs results in activation of a CaMKII-dependent signaling pathway resulting in modulation of intracellular Ca2+ availability and handling leading to increases in CM contractile function. Cardiac TRPA1 ion channels may represent a novel therapeutic target for increasing the inotropic and lusitropic state of the heart. 相似文献
Communicated by Ramaswamy H. Sarma 相似文献
The highest absorbed of them occurred in concentration 0.001N, which highest Pb2+ accumulation is in the aerial parts of the plant: leaf > stem > root and for Ni2+: root > stem > leaf. No ion was observed into the flowers and nickel ion absorption is more of lead ion in different plant organs of CTC.
The experimental isotherm data were investigated using isotherms of Langmuir, Freundlich, BET, Temkin and Dubinin–Radushkevich (DRK). The correlation coefficient for all of them is calculated that show the best correlation coefficient for Ni2+ adsorption is obtained BET model, whereas for Pb2+ adsorption in root is Freundlich model but for its leaf and stem is BET model. The results show, CTC is suitable for Pb2+ and Ni2+ and this technique is in-situ method, simple, and low cost. 相似文献
Methods: Renal mitochondrial oxidative stress and Sirt3 activity, using Zucker diabetic fatty rats (ZDFRs) and cultured proximal tubular cells under high-glucose condition were evaluated.
Results: At 28 weeks of age, ZDFRs exhibited the increased urinary albumin/liver-type fatty acid-binding protein (L-FABP)/8-hydroxy-2'-deoxyguanosine (8-OHdG) excretion, histological tubular cell damage, compared to non-diabetic Zucker Lean rats. In renal mitochondria, acetylated isocitrate dehydrogenase2 (IDH2) and superoxide dismutase2 (SOD2), accompanied with mitochondrial oxidative stress and mitochondrial morphologic alterations, were increased in ZDFRs, indicating inactivation of Sirt3. Additionally, expression of the NAD-degrading enzyme, CD38, was increased, and the NAD+/NADH (reduced NAD) ratio was reduced in the renal cortex of ZDFRs. High-glucose stimulation in cultured proximal tubular cells also resulted in an increase in acetylated IDH2/SOD2, CD38 overexpression and a reduction in the NAD+/NADH ratio.
Conclusions: Enhancement of mitochondrial oxidative stress in the diabetic kidney was mediated by the reduction of Sirt3 activity. CD38 overexpression may be related to a reduction in the NAD+/NADH ratio in the diabetic kidney. 相似文献
Materials and methods: The effect of five days oral administration of TiO2NPs (21 and 80?nm) with different doses (50, 250 and 500?mg/kg body weight) was assessed in mice via measurement of oxidative stress markers; glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and nitric oxide (NO), liver function indices; aspartate and alanine aminotransferases (AST and ALT), chromosomal aberrations and liver histopathological pattern.
Results: The results revealed drastic alterations in all the measured parameters and showed positive correlation with the gradual dose increment. In addition, the smaller particle size of TiO2NPS (21?nm) had more adverse effect in all the selected biochemical parameters, genetic aberrations and histological investigations.
Conclusions: Toxicity of TiO2NPs increases in a dose-dependent manner and vice versa with particles size. The evaluated biomarkers are good indicators for TiO2NPs toxicity. More detailed studies are required before the recommendation of TiO2NPS as food additives. 相似文献
Aims: To characterise native root-nodule bacteria isolated from B. pelecinus from the Iberian Peninsula, and to select suitable N fixers for field-application and soil rehabilitation.
Methods: Strains were isolated and molecularly identified by 16S rRNA amplification and sequencing. Strains were phenotypically characterised in different abiotic conditions (acidity, salinity and heavy metals) and tested for their ability to fix atmospheric N2. The most suitable N fixers were applied in greenhouse experiments with B. pelecinus under different fertilization levels to assess their tolerance to fertilized and polluted soils, commonly encountered in restoration projects.
Results: B. pelecinus root-nodule isolates tolerated pH from 4.5 to 9.5 grew in saline conditions (2.5% of NaCl), and tolerated 50 µM of Al3+ and Mn2+. Three isolates efficient in N2 fixation, relative to the reference Mesorhizobium strain, were considered excellent candidates for the amelioration of nutrient poor sites.
Conclusions: These results provide valuable information for the potential use in soil restoration of B. pelecinus in a wide-range of conditions, exploiting the natural variability of its root-nodule bacteria. 相似文献
Communicated by Ramaswamy H. Sarma 相似文献
Objective: For stable encapsulation of DOX into liposomes, we prepared triethylamine (TEA)-PGA-liposomes using PGA as an internal trapping agent.
Methods: We prepared TEA-PGA-liposomes by remote loading of DOX with a TEA gradient into preformed liposomes prepared with 1, 2, or 4?mg/mL PGA (molecular weights 4800, 9800, and 20 500), and evaluated their biodistribution and antitumor effects on Lewis lung carcinoma (LLC) tumor-bearing mice.
Results: TEA-PGA-liposomes using the higher the molecular weight or concentration of PGA showed a slower release of DOX from the liposomes. TEA-PGA-liposomes prepared with a high concentration of PGA could enhance DOX accumulation in tumors and prolonged DOX circulation in the serum, indicating that DOX may be retained stably in the liposomal interior by interaction with PGA. Furthermore, injection of TEA-PGA-liposomes prepared with 4?mg/mL of PGA9800 or 2?mg/mL PGA20500 strongly inhibited tumor growth in LLC tumor-bearing mice.
Conclusions: PGA may be a potential trapping agent for liposomal DOX for tumor drug delivery. 相似文献
Methods: Angiography and intravascular ultrasound were performed in 10 patients with MB with varying severities of systolic compression in the left anterior descending (LAD) artery. Computer models of MB were developed and transient computational fluid dynamics simulations were performed to derive distribution of blood residence time and shear stress.
Results: With increasing the severity of bridge compression, a decreasing trend was observed in the shear stress over proximal segment whereas an increasing trend was found in the shear stress over bridge segment. When patients were divided into 2 groups based on the average systolic vessel compression in the whole cohort (%CRave = 27.38), patients with bridges with major systolic compression (>%CRave) had smaller shear stress and higher residence time in the proximal segment compared to those with bridges with minor systolic compression (<%CRave) (0.37?±?0.23 vs 0.69?±?0.29?Pa and 0.0037?±?0.0069 vs 0.022?±?0.0094?s). In contrast, patients with bridges with major systolic compression had greater shear stress in the bridge segment compared to those with bridges with minor systolic compression (2.49?±?2.06 vs 1.13?±?0.89?Pa). No significant difference was found in the distal shear stress of patients with bridges with major and minor systolic compression.
Conclusion: Our findings revealed a direct relationship between the severity of systolic compression of MB and haemodynamic perturbations in the proximal segment such that the increased systolic vessel compression was associated with decreased shear stress and increased blood residence time. 相似文献
Objective: We compared the release of cardiac troponin T (cTnT) after endurance running in training-experience, biological-age and maturity-matched young male and female runners.
Materials and methods: Nineteen male (training history: 2.3?±?1.0?years; mean age: 16.1?±?1.2?years; Tanner stage: 3.7?±?0.6) and 19 female (training history: 2.2?±?1.0?years; mean age: 15.9?±?1.4?years; Tanner stage: 4.0?±?0.4) runners performed a 21?km run with “all-out” effort. Serum cTnT levels were assessed at pre-exercise (Pre-ex) and at 4?h post-exercise (Post-ex).
Results: At Pre-ex, cTnT concentrations were below the 99th percentile value (10?ng.l?1) in 32/38 runners. Post-ex cTnT increased in all subjects but the response was substantially higher (p?<?0.05) in males [median (range): 210 (20–1360) ng.l?1] than females [median (range): 80 (10–550) ng.l?1]. At Post-ex, 95% (95% confidence interval: 75–99%) of males and 63% (95% confidence interval: 41–81%) of females (p?<?0.05) had cTnT concentrations above the cut-off for acute myocardial infarction.
Conclusions: The present data suggest that post-exercise cTnT elevation occurs in all runners but is augmented in young male compared to female athletes. 相似文献
Objective: In this context, we decided to investigate the kinetic and mechanistic aspects of Vancomycin (Vanco) photosensitized degradation in the presence of the natural pigment Riboflavin (Vitamin B2, Rf) and the artificial dye Rose Bengal (RB) for comparative purposes.
Methods: The study have been done by using Stationary photolysis, Laser flash photolysis, Time-resolved phosphorence detection of O2(1Δg) experiments and Bactericidal activity evaluation. The experiments were carried out in aqueous solution at different pH values in order to establish relationships between the structure of the compound and its susceptibility to ROS-mediated photooxidation.
Results: Experimental evidence indicates that in the presence of Rf there is considerable contribution of the radical-mediated mechanism, while in the presence of RB the photooxidation process occurs exclusively through O2(1Δg) and the reactivity to this excited species increases with increasing pH of the environment.
Discussion: The results obtained, have been shown that Rf can raise the photodegradation of Vanco by both the radical pathway and the O2(1Δg) mediated. Furthermore, the antibiotic is able to interact with the excited electronic states of Rf as well as O2(1Δg) generated by energy transfer between the excited triplet state of the photosensitizer and the oxygen ground state. The predominant mechanism for photodegradation of Vanco in the presence of the Rf is the radical via because of the considerable interaction with the excited triplet state of the photosensitizer demonstrated by laser flash photolysis experiments.
Microbiological test on Staphylococcus aureus ATCC25923 showed that the bactericidal activity of the antibiotic on the strain studied was affected by the sensitized photodegradation process, suggesting that photoproducts generated eventually do not retain the bactericidal properties of the original antibiotic. 相似文献
Materials and Methods: BMSCs from C57BL/6 J mice were isolated and the third passage was used for subsequent experiments. Additionally, a series of in vitro transwell coculture assays were performed to explore the effects of BMSCs on the proliferation of MM cells 5TGM1 and CD4+ T cells. Furthermore, a 5TGM1-induced MM mice model was established. Moreover, PD-L1 shRNA was transfected into BMSCs to investigate whether PD-1/PD-L1 pathway involved in BMSCs-mediated regulation of T cells and MM growth.
Results: Data revealed that BMSCs significantly promoted 5TGM1 proliferation in a dose-dependent manner. Furthermore, BMSCs administration exerted stimulatory effects on MM development in terms of shortening the mouse survival rate, promoting tumor growth, and enhancing inflammatory infiltration in the MM model mice. Moreover, BMSCs decreased the percentage of Th1 and Th17 cells, whereas increased that of Th2 and Treg cells. Their corresponding cytokines of these T cell subsets showed similar alteration in the presence of BMSCs. Additionally, BMSCs significantly suppressed CD4+ T cell proliferation. We also found that PD-L1 shRNA inhibited 5TGM1 proliferation likely through activation of CD4+ T cells. Further in vivo experiments confirmed that PD-L1 inhibition attenuated BMSCs-induced MM growth, inflammation infiltration and imbalance of Th1/Th2 and Th17/Treg.
Conclusion: In summary, our findings demonstrated that BMSCs promoted cell proliferation of MM through inhibiting T cell immune responses via PD-1/PD-L1 pathway. 相似文献