LncRNA SH3BP5-AS1 promotes hepatocellular carcinoma progression by sponging miR-6838-5p and activation of PTPN4.

BACKGROUND: Long noncoding RNAs (LncRNAs) have been demonstrated to have significant roles in the carcinogenesis of hepatocellular carcinoma (HCC). In this work, we sought to determine LncRNA SH3BP5-AS1's function and mechanism in the emergence of HCC. RESULTS: First, we discovered that the advanced tumor stage was strongly correlated with high levels of LncRNA SH3BP5-AS1 expression in HCC. MiR-6838-5p expression was down-regulated and inversely correlated with SH3BP5-AS1 expression. Additionally, overexpression of SH3BP5-AS1 boosted cell invasion, migration, and proliferation. The oncogenic effects of the inhibitor of miR-6838-5p were eliminated when PTPN4 was suppressed, following the identification of PTPN4 as a direct target of miR-6838-5p. In addition, SH3BP5-AS1 promoted cellular glycolysis via miR-6838-5p sponging and PTPN4 activation. Lastly, by directly interacting to the promoter of SH3BP5-AS1, HIF-1α could control the transcription of the gene. CONCLUSIONS: Our research suggests that SH3BP5-AS1 controls miR-6838-5p/PTPN4 in order to act as a new carcinogenic LncRNA during the growth of HCC cells. METHODS: The expression levels of SH3BP5-AS1, miR-6838-5p and PTPN4 were detected by qRT-PCR and Western blot. The effects of LncRNA SH3BP5-AS1/miR-6838-5p/PTPN4 on the proliferation, metastasis and glycolysis of HCC cells were clarified by experimental cellular functionality assays, cell derived xenograft and Glycolysis assay.

Associations between estimation of salt intake and salt-restriction spoons and hypertension status in patients with poorly controlled hypertension: a community-based study from Huzhou City, Eastern China.

BACKGROUND: As the prevalence of hypertension increases in China, it is advised to use salt-restriction spoons (SRS) as a lifestyle modification. This study aimed to examine the associations between estimated salt consumption, SRS usage, and the hypertension status in individuals with poorly controlled hypertension. METHODS: Data was collected in Huzhou City, Zhejiang Province, in 2021 using convenience sampling. The analysis involved ordinal logistic regression and restricted cubic splines to assess the relevant factors. RESULTS: The study found that 73.34% of the 1215 patients had uncontrolled blood pressure (BP). Urinary excretion was assessed through the utilization of the Kawasaki, INTERSALT, and Tanaka formulas. The outcomes of these three methodologies revealed average daily sodium excretion values of 208.70 (65.65), 154.78 (33.91), and 162.61 (40.87) mmol, respectively. The prevalence of utilizing SRS was found to be 37.78% in this study. Despite the acknowledgment among SRS users of the potential hazards associated with excessive salt consumption, there exists a contradictory pattern of attitudes and behaviors concerning salt reduction. Among individuals with different levels of salt intake (quartiles 1-4, Q1 vs Q4), there was a positive association between limiting salt and hypertension status when controlling for other variables (Kawasaki adjusted OR = 0.58, 95% CI = 0.43-0.79; INTERSALT adjusted OR = 0.62, 95% CI = 0.41-0.92; Tanaka adjusted OR = 0.61, 95% CI = 0.45-0.92, p < 0.05). Our research also revealed that using or used SRS was a protective factor for blood BP control (adjusted OR = 0.79, 95% CI = 0.64-0.99, P < 0.05). The restricted cubic spline plots illustrated a monotonic upward relationship between estimated 24-h urinary Na and BP (P-overall association < 0.05; P-non-linear association > 0.05). CONCLUSIONS: The use of dietary SRS could result in decrease in daily salt intake for BP control in patients with poorly controlled hypertension. To reduce the impact of high BP in China, additional studies are required to create interventions that can enhance the results for patients.

Temporal and spatial dynamic changes of planktonic bacteria community structure in Li River, China: a seasonal survey.

A combined temporal and spatial research approach helps us to evaluate the ecological status of a river scientifically and comprehensively. To understand the response mechanisms of bacteria in the Li River to different environments, we conducted a 1-year study (2020-2021) and collected water samples from 18 sections of the river in October, January, April, and August. 16S sequencing was used to study the composition and structure of bacterial communities in Li River at different temporal and spatial scales. The results showed that NO3--N, TP, T, pH, and DO were significantly different on spatial and temporal scales. Alpha diversity of planktonic bacteria in Li River fluctuated significantly with the season, reaching its highest in summer. Proteobacteria remained the most dominant phylum in all seasons, but the differential microorganisms varied between seasons. Although the abundance of metabolic functions of planktonic bacteria did not show significant differences between seasons, we found that DO, TP, T, and COD were the key environmental factors affecting bacterial metabolism. In addition, the co-occurrence network analysis showed that the autumn network had a higher number of nodes and edges and exhibited a high degree of complexity, while the summer network had the highest degree of modularity and exhibited greater stability. These results deepen our knowledge of the response mechanisms of river microorganisms to temporal and spatial changes and provide a scientific reference for the study of river ecosystems.

Enhanced Heterogeneous Peroxymonosulfate Activation by MOF-Derived Magnetic Carbonaceous Nanocomposite for Phenol Degradation.

Degradation efficiency and catalyst stability are crucial issues in the control of organic compounds in wastewater by advanced oxidation processes (AOPs). However, it is difficult for catalysts used in AOPs to have both high catalytic activity and high stability. Combined with the excellent activity of cobalt/copper oxides and the good stability of carbon, highly dispersed cobalt-oxide and copper-oxide nanoparticles embedded in carbon-matrix composites (Co-Cu@C) were prepared for the catalytic activation of peroxymonosulfate (PMS). The catalysts exhibited a stable structure and excellent performance for complete phenol degradation (20 mg L-1) within 5 min in the Cu-Co@C-5/PMS system, as well as low metal-ion-leaching rates and great reusability. Moreover, a quenching test and an EPR analysis revealed that ·OH, O2·-, and 1O2 were generated in the Co-Cu@C/PMS system for phenol degradation. The possible mechanism for the radical and non-radical pathways in the activation of the PMS by the Co-Cu@C was proposed. The present study provides a new strategy with which to construct heterostructures for environmentally friendly and efficient PMS-activation catalysts.

Torrefaction characteristics of cellulose loaded with boric acid.

To explore the catalytic effect of boric acid on biomass, cellulose loaded with boric acid was roasted by a tubular furnace. The gaseous products were adsorbed by activated carbon and then analyzed by GC-MS. Boric acid was shown to improve the selectivity of the product levoglucosenone (LGO). The effects of the parameters such as boric acid loading, nitrogen flow, and temperature on the torrefaction behavior of cellulose were investigated. In the studied temperature range of 240-420 °C, the yield of LGO first increases and then decreases. In addition, its yield increases directly with increasing nitrogen flow rate. The results show that the highest LGO yield of 6.64% (analytical value) can be obtained under 10% (w/w) boric acid loading, 380 °C and nitrogen flow rate of 65 ml/min conditions.

Prevalence and influencing factors of comorbidity of chronic diseases among hypertensive patients with uncontrolled blood pressure in Huzhou City / 预防医学

Objective@#To investigate the prevalence and influencing factors of comorbidity of chronic diseases among hypertensive patients with uncontrolled blood pressure in Huzhou City, so as to provide insights into community hypertension control. @*Methods@#Hypertensive patients with uncontrolled blood pressure at ages of 35 to 74 years were sampled using a cluster random sampling method from 5 districts (counties) of Huzhou City. Participants' demographics, living behaviors, and development of chronic diseases were collected using questionnaires, and the height, body weight, waist circumference and blood pressure were measured. Blood glucose, blood lipid and other biochemical parameters were detected, and the number and combination of comorbidity of chronic diseases were descriptively analyzed. Factors affecting the comorbidity of chronic diseases were identified using a multivariable ordinal logistic regression model.@*Results@# A total of 1 215 respondents were included, with a mean age of (60.83±7.76) years, and including 652 men (53.66%) and 563 women (46.34%). The prevalence of dyslipidemia, diabetes, hyperuricemia and cardiac encephalopathy was 45.10%, 30.95%, 23.05% and 5.10%, respectively. The prevalence of comorbidity of chronic diseases was 69.22% among respondents, and there were 497 respondents with one comorbidity (40.91%), 272 with two comorbidities (22.39%) and 72 with three and more comorbidities (5.93%). Hypertension+dyslipidemia (20.74%), hypertension+diabetes+dyslipidemia (9.96%) and hypertension+diabetes+dyslipidemia+hyperuricemia (4.36%) were predominant comorbid combinations. Multivariable ordinal logistic regression analysis showed that participants with overweight (OR=1.782, 95%CI: 1.390-2.286), obesity (OR=2.411, 95%CI: 1.802-3.222), grade 2 hypertension (OR=1.438, 95%CI: 1.077-1.919) had a higher risk of multiple comorbidities than those with normal body mass index and controlled blood pressure, and women (OR=0.563, 95%CI: 0.456-0.696) had a lower risk of multiple comorbidities than men. @*Conclusions@#The prevalence of comorbidity of chronic diseases was 69.22% among community hypertensive patients with uncontrolled blood pressure in Huzhou City, and the comorbidity of chronic diseases mainly included dyslipidemia and diabetes. Men, overweight, obesity and hypertension resulted in a high risk of comorbidity of chronic diseases.

miR-382-5p promotes cell invasion in hepatocellular carcinoma by targeting PTEN to activate PI3K/Akt signaling pathway.

PURPOSE: This study aimed at investigating miR-382-5p expression in tissues and cell lines with hepatocellular carcinoma (HCC), its effects on the invasion of HCC cells, and related mechanisms. METHODS: miR-382-5p expression in HCC tissues, adjacent tissues, cell lines of normal hepatic cells, and HCC cells were detected by qRT-PCR, indicating its upregulation or downregulation in HCC cell lines (Hep3B and HCCLM3). The effect of miR-382-5p on cell invasion was observed by the Transwell experiment. The targeting relationship of miR-382-5p and the phosphatase and tensin homolog (PTEN) was analyzed using bioinformatics tools and the luciferase reporter gene assay. The correlation between miR-382-5p and PTEN was analyzed with Spearman correlation analysis. PTEN expression was observed after upregulation and downregulation of miR-382-5p expression. The effect of miR-382-5p on the expression of key proteins in PI3K/Akt signaling pathway was determined by Western blot. RESULTS: miR-382-5p expression was upregulated in both HCC tissues and cell lines (both P<0.05). Upregulation or downregulation of miR-382-5p significantly promoted or inhibited the invasion of cell lines, Hep3B, and HCCLM3. The luciferase reporter gene assay confirmed that PTEN is a target of miR-382-5p. The expressions of miR-382-5p and PTEN were negatively correlated (r=-0.742, P<0.001). Upregulation of PTEN expression by plasmid transfection can reverse the invasive effect of miR-382-5p on HCC cells. Upregulation of miR-382-5p can activate PI3K/Akt signaling pathway, and downregulation of miR-382-5p can inhibit PI3K/Akt signaling pathway. CONCLUSIONS: miR-382-5p can activate the PI3K/Akt signaling pathway by targeting PTEN and promote HCC cell invasion.

The potential of a natural iron ore residue application in the efficient removal of tetracycline hydrochloride from an aqueous solution: insight into the degradation mechanism.

In the existing research, most of the heterogeneous catalysts applied in the activation of persulfate to degrade organic pollutants were synthesized from chemical reagents in the laboratory. In this paper, we have obtained a spent iron ore (IO) residue directly collecting from the iron ore plants, and efficiently activating peroxydisulfate (PS) to produce reactive free radicals. The experimental results demonstrated that the IO could effectively activate PS to degrade tetracycline hydrochloride (TCH), with TCH removal rate reaching up to 85.6% within 2 h at room temperature. The TCH removal rate was increased with increasing iron ore dosage, while the more acidic pH condition would be favorable to TCH removal process. The material characterization results demonstrated that the dominant components of IO were Fe3O4 and FeOOH. The transformation from Fe(II) to Fe(III) at the surface IO was observed after TCH degradation. What's more, the quenching experiment and EPR detection results confirmed that the sulfate radical (SO4•-) and hydroxyl radicals (•OH) would be acting as the main free radicals for TCH degradation. This study could not only explore a novel way to recycle the discarded iron ore, but also further expand its application in an effective activation of PS in an aqueous solution.

UV-assisted nitrogen-doped reduced graphene oxide/Fe3O4 composite activated peroxodisulfate degradation of norfloxacin.

We reported the preparation of NGO-Fe3O4 by simple hydrothermal-co-precipitation. The catalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). It was demonstrated that norfloxacin (NOR) could be effectively degraded by the UV/NGO-Fe3O4/PDS system. The degradation efficiency reached 100% within 13 min (the concentration of NOR and S2O82- were 100 mg L-1 and 1 mM, respectively; m(NGO-Fe3O4): m(PDS) = 4: 1; pH: 3.0). In addition, NGO-Fe3O4 showed stable catalytic activity in recycling. The analysis found that the in-situ generated ·OH was the main active free radicals but SO4-⋅ also participated in the NOR degradation. Based on the identified intermediates, the NOR degradation pathways were proposed with UV/NGO-Fe3O4/PDS system.

A feasible biochar derived from biogas residue and its application in the efficient adsorption of tetracycline from an aqueous solution.

The recovery of carbon materials from biogas residue (BR) could efficiently promote the efficient utilization of waste and the preparation of novel materials. In this study, a green and feasible reagent of citric acid was introduced and applied in the modification of biogas residue biochar (BRC). The modified biogas residue biochar (CABRC) showed a superior adsorption ability due to its higher specific surface area (approximately 6 times that of the BRC). Additionally, the adsorption capacities of CABRC and BRC for TC were 58.25 mg/g and 20.77 mg/g, respectively, while the TC adsorption performance of CABRC was 2.8 times that of BRC. The adsorption of TC by both BRC and CABRC was primarily controlled by physical adsorption and chemical adsorption (including pore filling, hydrogen bonding, π-π DEA interaction, and electrostatic interaction). Therefore, CABRC should be considered an environmentally friendly material due to its higher adsorption performance, which could expand its application in wastewater treatment.

Potential Application of Discarded Natural Coal Gangue for the Removal of Tetracycline Hydrochloride (TC) from an Aqueous Solution.

The generation and accumulation of discarded coal gangue (CG) have severe environmental impacts. CG can adsorb other pollutants in the aquatic environment. However, previous studies have not assessed whether CG can adsorb the emerging contaminant tetracycline hydrochloride (TC). Here, discarded CG taken from a mine was pretreated by crushing, cleaning, and sieving and subsequently applied to the adsorption of TC. The adsorption studies were carried out by batch equilibrium adsorption experiments. Our findings indicated that the adsorption behavior could be accurately described using the quasi-first order kinetic and Langmuir adsorption isotherm models, indicating that monolayer adsorption was the main mechanism mediating the interaction between CG and TC. The adsorption process was classified as a thermodynamic endothermic and spontaneous reaction, which was controlled by chemical and physical adsorption, including electrostatic interaction and cation exchange. The pH of the solution had a great influence on the TC adsorption capacity of GC, with higher adsorption occurring in acidic environments compared to alkaline environments. This was attributed to the changes in CG Zeta potential and TC pKa at different pH conditions. Collectively, our findings demonstrated the potential applicability of discarded CG for the adsorption of TC and provided insights into the adsorption mechanisms.

Analysis of the Influencing Factors of the Hydroxyl Radical Yield in a Hydrodynamic Cavitation Bubble of a Chitosan Solution Based on a Numerical Simulation.

In this paper, the hydroxyl radical yield of a cavitation bubble and its influencing factors in the process of chitosan degradation with hydrodynamic cavitation in a single-hole orifice plate was investigated by a numerical simulation method. The hydroxyl radical yield of the cavitation bubble was calculated and analyzed by the Gilmore equation as the dynamic equation combined with the mass transfer equation, heat transfer equation, energy balance equation, and the principle of Gibbs free energy minimization. The influence of geometric parameters of the orifice plate and operating parameters on the formation of hydroxyl radicals was investigated. The results showed that the hydroxyl radicals produced at the moment of cavitation bubble collapse increased with the increase of the initial radius (R 0), upstream inlet pressure (P 1), downstream recovery pressure (P 2), downstream pipe diameter (d p), and the ratio of the orifice diameter to the pipe diameter (ß). The simulation results provide a certain basis for the regulation of hydrodynamic cavitation degradation of chitosan.

Preparation of ß-cyclodextrin/graphene oxide and its adsorption properties for methylene blue.

Graphene oxide (GO) and GO-based materials have shown excellent adsorption properties because of bounteous structure and rich oxygen functional groups. Many studies have shown that GO are utilized as adsorbents to remove organic dyes from wastewater. GO was prepared by modified Hummers method using graphite powder as raw material. On this basis, ß-cyclodextrin/graphene oxide composite (ß-CD/GO) was prepared by modifying graphene oxide via ß-cyclodextrin(ß-CD) crosslinking method. GO and ß-CD were characterized by Fourier transform infrared spectroscopy (FT-IR), energy-dispersive X-ray (XRD), scanning electron (SEM) and thermogravimetric analysis (TGA). Their adsorbents properties have been studied with methylene blue (MB) as adsorbate. The factors affecting the study include the temperature, adsorption time, amount of adsorbent and system pH value. Adsorption isotherm and kinetics of the adsorption process are systematically analyzed. The results show that ß-CD/GO has a different adsorption capacity from GO under the same adsorption factors. Under the optimized conditions (the reaction temperature is 70 °C, the reaction time is 60 min and the concentration of adsorbent is 0.04 g/L), the removal efficiency of ß-CD/GO is 20% higher than that of GO from 70% to 90%. The maximum adsorption capacity of ß-CD/GO is 76.4 mg/g. ß-CD/GO can be effectively regenerated by elution with absolute alcohol. In these tests, ß-CD/GO was suggested to be more efficient than GO in the removal of organic dyes.

MicroRNA-3651 promotes the growth and invasion of hepatocellular carcinoma cells by targeting PTEN.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common malignant tumors in human worldwide. Evidence indicated that upregulation of microRNA-3651 (miR-3651) was observed in human HCC tissues. In this study, we explored the mechanisms by which miR-3651 regulated the proliferation, apoptosis and invasion of HCC. METHODS: The levels of miR-3651 in human HCC tissues were detected using qRT-PCR assay. In addition, transwell invasion and Western blot assay were conducted to detect cell invasion and apoptosis, respectively. Meanwhile, the dual-luciferase reporter assay was used to explore the interaction of miR-3651 and phosphate and tension homology deleted on chromsome ten (PTEN) in HCC. RESULTS: The levels of miR-3651 were upregulated in HCC tissues in comparison with the matched normal tissues. Overexpression of miR-3651 significantly promoted the proliferation and invasion of Huh-7 cells. In contrast, inhibition of miR-3651 markedly inhibited the proliferation and invasion of Huh-7 cells via promoting apoptosis. Moreover, downregulation of miR-3651 markedly inhibited tumor growth in vivo. Furthermore, bioinformatics analysis and luciferase reporter assay identified that PTEN was the directly binding target of miR-3651 in Huh-7 cells. Meanwhile, overexpression of miR-3651 obviously decreased the level of PTEN, and increased the expressions of p-p85 and p-Akt in Huh-7 cells. CONCLUSION: These results indicated that miR-3651 might act as a potential oncogene in HCC by targeting PTEN. Therefore, miR-3651 might be a novel therapeutic target for the treatment of HCC.

A green recycling process of the spent lead paste from discarded lead-acid battery by a hydrometallurgical process.

In this study, a green recycling process of discarded lead-acid battery paste, which could avoid both the smelting and electro-winning route has been developed. Leaching reagents containing sodium citrate, acetic acid and hydrogen peroxide were reacted with spent lead paste in aqueous media at the pH of 5-6. Lead paste was leached and formed into lead citrate precursor, which was recrystallized and separated from the solution. The optimal conditions for the leaching process at room temperature were found to be the: concentration of acetic acid solution of 0.92 mol L-1; concentration of sodium citrate solution of 0.478 mol L-1; initial mass ratio of solid spent lead paste to liquid (solid/liquid ratio) of 1/5 g/mL; and reaction time of 2 hours. The results showed that the desulphurization efficiency of lead paste was up to 99.9%. The optimal conditions for lead citrate re-crystallization from the leaching mixed solution were found to be the re-crystallization temperature of 55oC for 5 hours in a water bath. The lead citrate precursor synthesized from discarded lead-acid battery pastes was the chemical formula of Pb3(C6H5O7)2·3H2O with columnar shape in the length of 30-50 µm, which was easily separated from the leaching solution. The results of kilogram-scale experiments made progress easier for obtaining the ultrafine lead oxide product (PbO and Pb) from discarded lead-acid battery paste.

The Guizhi Gancao Decoction Attenuates Myocardial Ischemia-Reperfusion Injury by Suppressing Inflammation and Cardiomyocyte Apoptosis.

Guizhi Gancao Decoction (GGD) is a well-known traditional Chinese herbal medicine for the treatment of various cardiovascular diseases, such as myocardial ischemia-reperfusion (I/R) injury and arrhythmia. However, the mechanism by which GGD contributes to the amelioration of cardiac injury remains unclear. The aim of this study was to investigate the potential protective role of GGD against myocardial I/R injury and its possible mechanism. Consistent with the effect of the positive drug (Trimetazidine, TMZ), we subsequently validated that GGD could ameliorate myocardial I/R injury as evidenced by histopathological examination and triphenyltetrazolium chloride (TTC) staining. Moreover, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay demonstrated that GGD suppressed myocardial apoptosis, which may be related to the upregulation of Bcl-2, PPARα, and PPARγ and downregulation of Bax, caspase-3, and caspase-9. Pretreatment with GGD attenuated the levels of proinflammatory cytokines including tumor necrosis factor-α (TNF-α), interleukin- (IL-) 6, and IL-1ß in serum by inhibiting Toll-like receptor 4 (TLR4)/NF-κB signaling pathway. These results indicated that GGD exhibits cardioprotective effects on myocardial I/R injury through inhibition of the TLR4/NF-κB signaling pathway, which led to reduced inflammatory response and the subsequent cardiomyocyte apoptosis.

Immunization with functionalized carbon nanotubes enhances the antibody response against mode antigen ovalbumin.

Carbon nanotubes (CNTs) have attracted considerable attention because of their potential application as a new nonvehicle. We have covalently conjugated the mode antigen ovalbumin (OVA) to functionalized multi-walled carbon nanotubes. Herein, we explored the underlying theoretical mechanisms of CNTs' immunological adjuvant characterization. In vitro, the efficiency of cellular uptake of MWCNT-OVA into DC2.4 cells was improved over that of pure-antigen OVA. The costimulators (CD40/86), the major histocompatibility complex MHCII molecules, and the CD11c molecules were found to be upregulated. Further in vivo experiments established that the MWCNT-OVA group enhanced the IL-1ß, TNF-α, and IL-6 cytokine secretion, suggesting that MWCNT reinforced the immune response using different cytokine pathways. Anti-OVA antibodies after inoculation of MWCNT-OVA into mice were measured. The medium dose of MWCNTs conjugated with OVA induced the highest level of OVA-specific antibodies at day 82 and have a synergistic effect with the commercial Freund's adjuvant. MWCNTs-KLH-MC-LR also induced higher levels of MC-LR-specific antibody than did KLH-MC-LR. MWCNTs also could activate the complement system which is closely related with humoral immunity. These results suggested that MWCNTs enhance the immune response and show excellent inherent characteristics to be applied as an adjuvant.

All-Trans Retinoic Acid-Induced Deficiency of the Wnt/ß-Catenin Pathway Enhances Hepatic Carcinoma Stem Cell Differentiation.

Retinoic acid (RA) is an important biological signal that directly differentiates cells during embryonic development and tumorigenesis. However, the molecular mechanism of RA-mediated differentiation in hepatic cancer stem cells (hCSCs) is not well understood. In this study, we found that mRNA expressions of RA-biosynthesis-related dehydrogenases were highly expressed in hepatocellular carcinoma. All-trans retinoic acid (ATRA) differentiated hCSCs through inhibiting the function of ß-catenin in vitro. ATRA also inhibited the function of PI3K-AKT and enhanced GSK-3ß-dependent degradation of phosphorylated ß-catenin. Furthermore, ATRA and ß-catenin silencing both increased hCSC sensitivity to docetaxel treatment. Our results suggest that targeting ß-catenin will provide extra benefits for ATRA-mediated treatment of hepatic cancer patients.

Specific binding and inhibition of 6-benzylaminopurine to catalase: multiple spectroscopic methods combined with molecular docking study.

6-Benzylaminopurine (6-BA) is a kind of cytokinin which could regulate the activities of the antioxidant defense system of plants. In this work, its interaction with and inhibition of beef liver catalase have been systematically investigated using spectroscopic, isothermal titration calorimetric and molecular docking methods under physiological conditions. The fluorescence quenching of beef liver catalase (BLC) by 6-BA is due to the formation of 6-BA-BLC complex. Hydrogen bonds and van der Waals interactions play major roles in stabilizing the complex. The Stern-Volmer quenching constant, binding constant, the corresponding thermodynamic parameters and binding numbers were measured. The results of UV-vis absorption, three-dimensional fluorescence, synchronous fluorescence and circular dichroism spectroscopic results demonstrate that the binding of 6-BA results in the micro-environment change around tyrosine (Tyr) and tryptophan (Trp) residues of BLC. The BLC-mediated conversion of H2O2 to H2O and O2, in the presence and absence of 6-BA, was also studied. Lineweaver-Burk plot indicates a noncompetitive type of inhibition. Molecular docking study was used to find the binding sites.

Leaching of spent lead acid battery paste components by sodium citrate and acetic acid.

A sustainable method, with minimal pollution and low energy cost in comparison with the conventional smelting methods, is proposed for treating components of spent lead-acid battery pastes in aqueous organic acid(s). In this study, PbO, PbO2, and PbSO4, the three major components in a spent lead paste, were individually reacted with a mixture of aqueous sodium citrate and acetic acid solution. Pure lead citrate precursor of Pb3(C6H5O7)2 · 3H2O is the only product crystallized in each leaching experiment. Conditions were optimized for individual lead compounds which were then used as the basis for leaching real industrial spent paste. In this work, efficient leaching process is achieved and raw material cost is reduced by using aqueous sodium citrate and acetic acid, instead of aqueous sodium citrate and citric acid as reported in a pioneering hydrometallurgical method earlier. Acetic acid is not only cheaper than citric acid but is also more effective in aiding dissolution of the lead compounds thus speeding up the leaching process in comparison with citric acid. Lead citrate is readily crystallized from the aqueous solution due to its low solubility and can be combusted to directly produce leady oxide as a precursor for making new battery pastes.