Double-edged effect of sodium citrate in Nile tilapia(Oreochromis niloticus):Promoting lipid and protein deposition vs.causing hyperglycemia and insulin resistance

Citrate is an essential substrate for energy metabolism that plays critical roles in regulating glucose and lipid metabolic homeostasis.However,the action of citrate in regulating nutrient metabolism in fish remains poorly understood.Here,we investigated the effects of dietary sodium citrate on growth performance and systematic energy metabolism in juvenile Nile tilapia(Oreochromis niloticus).A total of 270Nile tilapia(2.81±0.01 g)were randomly divided into three groups(3 replicates per group,30 fish per replicate)and fed with control diet(35%protein and 6%lipid),2%and 4%sodium citrate diets,respectively,for 8 weeks.The results showed that sodium citrate exhibited no effect on growth performance(P>0.05).The whole-body crude protein,serum triglyceride and hepatic glycogen contents were significantly increased in the 4%sodium citrate group(P<0.05),but not in the 2%sodium citrate group(P>0.05).The 4%sodium citrate treatment significantly increased the serum glucose and insulin levels at the end of feeding trial and also in the glucose tolerance test(P<0.05).The 4%sodium citrate significantly enhanced the hepatic phosphofructokinase activity and inhibited the expression of pyruvate dehydrogenase kinase isozyme 2 and phosphor-pyruvate dehydrogenase E1 component subunit alpha proteins(P<0.05).Additionally,the 4%sodium citrate significantly increased hepatic triglyceride and acetyl-Co A levels,while the expressions of carnitine palmitoyl transferase 1a protein were significantly down-regulated by the 4%sodium citrate(P<0.05).Besides,the 4%sodium citrate induced crude protein deposition in muscle by activating m TOR signaling and inhibiting AMPK signaling(P<0.05).Furthermore,the 4%sodium citrate significantly suppressed serum aspartate aminotransferase and alanine aminotransferase activities,along with the lowered expression of pro-inflammatory genes,such as nfκb,tnfa and il8(P<0.05).Although the 4%sodium citrate significantly increased phosphor-nuclear factor-k B p65 protein expression(P<0.05),no significant tissue damage or inflammation occurred.Taken together,dietary supplementation of sodium citrate could exhibit a double-edged effect in Nile tilapia,with the positive aspect in promoting nutrient deposition and the negative aspect in causing hyperglycemia and insulin resistance.

Sodium citrate and biochar synergistic improvement of nanoscale zero-valent iron composite for the removal of chromium(Ⅵ)in aqueous solutions

Sodium citrate(SC)is a widely-used food and industrial additive with the properties of com-plexation and microbial degradation.In the present study,nano-zero-valent iron reaction system(SC-nZVI@BC)was successfully established by modifying nanoscale zero-valent iron(nZVI)with SC and biochar(BC),and was employed to remove Cr(Ⅵ)from aqueous solu-tions.The nZVI,SC-nZVI and SC-nZVI@BC were characterized and compared using X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),thermogravimetric analy-ses(TGA),vibrating sample magnetometer(VSM),scanning electron microscope(SEM),X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS).The results showed that nZVI was successfully loaded on the biochar,and both the agglomeration and surface pas-sivation problems of nanoparticles were well resolved.The dosage of SC,C∶Fe,initial pH and Cr(Ⅵ)concentration demonstrated direct effects on the removal efficiency.The maximum Cr(Ⅵ)removal rate and the removal capacity within 60 min were 99.7%and 199.46 mg/g,respectively(C∶Fe was 1∶1,SC dosage was 1.12 mol.%,temperature was 25℃,pH=7,and the original concentration of Cr(Ⅵ)was 20 mg/L).The reaction confirmed to follow the pseudo-second-order reaction kinetics,and the order of the reaction rate constant k was as follows:SC-nZVI@BC>nZVI@BC>SC-nZVI>nZVI.In addition,the mechanism of Cr(Ⅵ)removal by SC-nZVI@BC mainly involved adsorption,reduction and co-precipitation,and the reduction of Cr(Ⅵ)to Cr(Ⅲ)by nano Fe0 played a vital role.Findings from the present study demon-strated that the SC-nZVI@BC exhibited excellent removal efficiency toward Cr(Ⅵ)with an improved synergistic characteristic by SC and BC.

Enhancement of Aminoacylase Activity by Sodium Citrate

Kidney and other tissues of animals and humans have a high concentration of citrate which is an important intermediate substance in the citrate cycle. Citrate may play an important physiological role in metabolism. In this paper, we studied the interaction of the sodium salt of citrate with aminoacylase which is an important enzyme in metabolism and found sodium citrate can enhance the activity of aminoacylase.The maximum enzyme activity induced by sodium citrate increased approximately 3 folds over the enzyme activity without sodium citrate. The initial reaction rates (V) for different concentrations of sodium citrate were obtained, showing that sodium citrate is a non competitive activator. The result of the ANS binding fluorescence measurements for aminoacylase indicated that increasing sodium citrate concentrations markedly increased the ANS binding fluorescence with a blue shift of the emission spectra peak. This suggests the formation of more hydrophobic regions. Aggregates formed quickly when aminoacylase was incubated with sodium citrate (0.3 mol/L) and guanidinium chloride (03.5 mol/L). Aminoacylase lost enzyme activity in the guanidinium chloride more quickly in the presence of sodium citrate than in the absence of sodium citrate. The intrinsic fluorescence emission intensity decreased more quickly and the red shift of the emission spectra peak was larger than that without sodium citrate.

Cleansing efficacy and safety of bowel preparation protocol using sodium picosulfate/magnesium citrate considering subjective experiences:An observational study

BACKGROUND Research data from patient reports indicate that the least bearable part of colonoscopy is the administration of laxatives for bowel preparation.AIM To observe the intestinal cleansing efficacy and safety of sodium picosulfate/magnesium citrate and to discuss the patients’experiences due to the procedure.METHODS Subjects hospitalized in the International Medical Center Ward of Peking University International Hospital,Beijing,China,from April 29 to October 29,2020,for whom the colonoscopy was planned,were enrolled.Bowel preparation was performed using sodium picosulfate/magnesium citrate.The effect of bowel cleansing was evaluated according to the Ottawa Bowel Preparation Scale,defecation conditions and adverse reactions were recorded,and the comfort level and subjective satisfaction concerning medication were evaluated by the visual analogue scale/score(VAS).RESULTS The bowel preparation procedure was planned for all patients enrolled,which included 42 males and 22 females.The results showed an average liquid rehydration volume of 3000 mL,an average onset of action for the first dose at 89.04 min,an average number of bowel movements of 4.3 following the first dose,an average onset of action for the second dose at 38.90 min and an average number of bowel movements of 5.0 after the second dose.The total average Ottawa Bowel Preparation Scale score was 3.6,with 93.55%of bowel preparations in the“qualified”and 67.74%in the“excellent”grade.The average VAS score of effect on sleep was 0,and the average VAS score of perianal pain was also 0.The average VAS score for ease of taking and taste perception of the bowel cleanser was 10.Side effects included mild to moderate nausea(15.63%),mild vomiting(4.69%),mild to moderate abdominal pain(7.81%),mild to moderate abdominal distension(20.31%),mild palpitation(7.81%)and mild dizziness(4.69%).CONCLUSION Sodium picosulfate/magnesium citrate is effective and safe for bowel preparation before colonoscopy with high subjective patient acceptance,thus improving overall patient compliance.

Bio-inspired Hydroxyapatite/Gelatin Transparent Nanocomposites

Hydroxyapatite(HA)nanoparticles impart outstanding mechanical properties to organicinorganic nanocomposites in bone.Inspired by the composite structure of HA nanoparticles and collagen in bone,a high performance HA/gelatin nanocomposite was first developed.The nanocomposites have much better mechanical properties(elongation at break 29.9%,tensile strength 90.7 MPa,Young’s modulus 5.24 GPa)than pure gelatin films(elongation at break 9.3%,tensile strength 90.8 MPa,Young’s modulus 2.5 GPa).In addition,the composite films keep a high transmittance in visible wavelength range from 0%to 60%of the HA solid content.These differences in properties are attributed to the homogeneous distribution of HA nanoparticles in the gelatin polymer matrix and the strong interaction between the particle surfaces and the gelatin molecules.This protocol should be promising for HA-based nanocomposites with enhanced mechanical properties for biomedical applications.

Therapeutic effects of potassium sodium hydrogen citrate on melamine-induced urinary calculi in China

Background In 2008, a sharp increase of the number of children diagnosed with urinary calculi was observed in China, 9433 children were diagnosed as having melamine-induced urinary calculi at outpatient clinic in Beijing Children＇s Hospital. This study examined the therapeutic efficacy of potassium sodium hydrogen citrate （PSHC） used to treat melamine-induced urinary stones in Chinese children who consumed melamine-containing infant formula. Methods Seventy-two infants and children （average age （18.2±7.7） months） who were diagnosed with urinary calculi were icuidomly divided into three treatment groups using the SAS Plan program. Group 1 was given a low dose （1 g/d） of PSHC, group 2 was given high dose of PSHC （2 g/d） and group 3 was given no PSHC （control group）. The dose of drug was adjusted according to the baseline urinary pH. This study analyzed the influence of the dose of PSHC, the age of patients, stone size and position, and urinary pH on the level of efficacy of PSHC （cured, effectively treated or not cured）.Results After 1-6 months of therapy, 19 patients from group 1, five patients from group 2 and six patients from group 3 were cured. Five patients from group 1, five patients from group 2 and four patients from group 3 were effectively treated. There were significant differences in therapeutic efficacy between the two treatment doses after 3 and 6 months as measured by the increase in the successful expulsion rate and time of melamine-induced urinary calculi. After 6 months the mean time of expulsion of urinary calculi in groups 1 and 2 was significantly shorter than in the control group. Conclusions PSHC can significantly increase the successful expulsion rate and time of melamine-induced urinary calculi. The therapeutic efficacy is affected by PSHC dose, treatment duration, calculi position, and urinary pH. There is no relationship between the therapeutic efficacy and the stone size or patient age.

Calcium-containing versus calcium-free replacement solution in regional citrate anticoagulation for continuous renal replacement therapy:a randomized controlled trial

Background: A simplified protocol for regional citrate anticoagulation (RCA) using a commercial calcium-containing replacement solution, without continuous calcium infusion, is more efficient for use in continuous renal replacement therapy (CRRT). We aim to design a randomized clinical trial to compare the safety and efficacy between calcium-free and calcium-containing replacement solutions in CRRT with RCA.Methods: Of the 64 patients receiving RCA-based postdilution continuous venovenous hemodiafiltration (CVVHDF) enrolled from 2017 to 2019 in West China Hospital of Sichuan University, 35 patients were randomized to the calcium-containing group and 29 to the calcium-free replacement solution group. The primary endpoint was circuit lifespan and Kaplan-Meier survival analysis was performed. Secondary endpoints included hospital mortality, kidney function recovery rate, and complications. The amount of 4% trisodium citrate solution infusion was recorded. Serum and effluent total (tCa) and ionized (iCa) calcium concentrations were measured during CVVHDF.Results: A total of 149 circuits (82 in the calcium-containing group and 67 in the calcium-free group) and 7609 circuit hours (4335 hvs. 3274 h) were included. The mean circuit lifespan was 58.1 h (95% CI 53.8-62.4 h) in the calcium-containing groupvs. 55.3 h (95% CI 49.7-60.9 h, log rankP = 0.89) in the calcium-free group. The serum tCa and iCa concentrations were slightly lower in the calcium-containing group during CRRT, whereas the postfilter iCa concentration was lower in the calcium-free group. Moreover, the mean amounts of 4% trisodium citrate solution infusion were not significantly different between the groups (171.1 ± 15.9 mL/hvs. 169.0 ± 15.1 mL/h,P = 0.49). The mortality (14/35 [40%]vs. 13/29 [45%],P = 0.70) and kidney function recovery rates of AKI patients (19/26, 73%vs. 14/24, 58%,P = 0.27) were comparable between the calcium-containing and calcium-free group during hospitalization, respectively. Six (three in each group) patients showed signs of citrate accumulation in this study.Conclusions: When compared with calcium-free replacement solution, RCA-based CVVHDF with calcium-containing replacement solution had a similar circuit lifespan, hospital mortality and kidney outcome. Since the calcium-containing solution obviates the need for a separate venous catheter and a large dose of intravenous calcium solution preparation for continuous calcium supplementation, it is more convenient to be applied in RCA-CRRT practice.

Catalytic decomposition of low level ozone with gold nanoparticles supported on activated carbon

Highly dispersed gold nanoparticles were supported on coal-based activated carbon(AC)by a sol immobilization method and were used to investigate their catalytic activity for low-level ozone decomposition at ambient temperature.Nitrogen adsorption-desorption,scanning electron microscope(SEM),and X-ray photoelectron spectroscopy(XPS)were used to characterize the catalysts before and after ozone decomposition.The results showed that the supported gold nanoparticles prepared with microwave heating were much smaller and more uniformly dispersed on the activated carbon than those prepared with traditional conduction heating,exhibiting higher catalytic activity for ozone decomposition.The pH values of gold precursor solution significantly influenced the catalytic activity of supported gold for ozone decomposition,and the best pH value was 8.In the case of space velocity of 120000 h–1,inlet ozone concentration of 50 mg/m3,and relative humidity of 45%,the Au/AC catalyst maintained the ozone removal ratio at 90.7%after 2500 min.After being used for ozone decomposition,the surface carbon of the catalyst was partly oxidized and the oxygen content increased accordingly,while its specific surface area and pore volume only decreased a little.Ozone was mainly catalytically decomposed by the gold nanoparticles supported on the activated carbon.

Accessory ligand strategies for hexacyanometallate networks deriving perovskite polycrystalline electromagnetic absorbents

The controllable adjustment of electromagnetic(EM)properties for high-efficiency EM absorbents are indispensable,nonetheless,rare in crystals engineering regulation.Herein,for the first time,regulated amount of sodium citrate was employed as accessory ligand of cobalt cation in aqueous solution to kinetically assist the controllable fabrication of Prussian blue analogs(PBAs)and corresponding lanthanide perovskite hybrid Co Fe alloy polycrystals.Especially,the multi-phase features were analyzed based on Rietveld refinement of XRD patterns,illustrating the existence of distortions,defects and heterogeneous interfaces in resultant polycrystals.Benefited to the dielectric and magnetic adjustment,polycrystalline absorbents achieved excellent impedance matching and EM attenuation,as the minimum reflection loss of Co Fe/La FeO_(3)and Co Fe/La FeO_(3)/La_(2)O_(3)reached-44.13 and-33.95 d B,ranking broadest effective bands up to 4.88 and 3.36 GHz.The validity of the strategy provided a novel sight into the controllable fabrication of high-performance magnetic semiconductor polycrystalline devices.

Layer-controlled Pt-Ni porous nanobowls with enhanced electrocatalytic performance

Hollow and porous Pt-based nanomaterials are promising catalysts with applications in many sustainable energy technologies such as fuel cells. Economical and green synthetic routes are highly desirable. Here, we report a facile approach to prepare double- and single-layered Pt-Ni nanobowls （DLNBs and SLNBs） with porous shells. Microstructural analysis revealed that the shells were constructed of alloyed Pt-Ni nanocrystals and small amounts of Ni compounds. X-ray photoelectron spectra showed that their Pt 4f binding energies shifted in the negative direction compared to those of the commercial Pt/C catalyst. Furthermore, the DLNBs contained greater contents of oxidized Ni species than the SLNBs. The layer-controlled growth processes were confirmed by microscopy, and a formation mechanism was proposed based on the assistance of citrate and poly（vinylpyrrolidone） （PVP）. For the methanol oxidation reaction, the DLNBs and SLNBs exhibited 2.9 and 2.5 times higher mass activities than that of the commercial Pt/C catalyst, respectively. The activity enhancements were attributed to electronic effects and a bifunctional mechanism. Chronoamperometry and prolonged cyclic voltammetry indicated that the Pt-Ni bowl-like structures had better electrochemical properties and structural stability than the commercial Pt/C catalyst, thus making the Pt-Ni nanobowls excellent electrocatalysts for use in direct methanol fuel cells.

Preparation and characterization of ZnO/ZnS hybrid photocatalysts via microwave-hydrothermal method

The photocatalytic performance of ZnO/ZnS hybrid nanocomposite was largely higher than that of the mere ZnO or ZnS nanoparticles,but the complicated procedure and misdistribution of final products limited its large-scale productions.The exploration of a novel synthesis route of ZnO/ZnS hybrid photocatalysts with high catalytic performance is becoming a crucial step for the large-scale application of ZnO/ZnS hybrid photocatalytic technique.Preparation and characterization of nanosized ZnO/ZnS hybrid photocatalysts were studied in this paper.The photocatalysts were obtained via microwavehydrothermal crystallization with the help of sodium citrate.The products were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),particle size distribution(PSD),and Fourier transformed infrared spectroscopy(FT-IR).The results indicated that so-synthesized ZnO/ZnS samples consisted of the high pure cubic(sphalerite)ZnS and hexagonal ZnO nanocrystallines with a narrow particle size distribution.The possible formation mechanisms of ZnO/ZnS nanocrystallines were mainly attributed to the superficially protective effect of citrate.The photocatalytic experiments demonstrated that the ZnO/ZnS photocatalysts exhibited a higher catalytic activity for the degradation of acid fuchsine than other monocomponents.