Citrate Solution Research Articles

Mechanisms of Surface Passivation during Galena Leaching by Hydrogen Peroxide in Acetate and Citrate Solutions at 25–50 °C

Organic solutions are promising lixiviants for fast and environmentally sustainable Pb extraction from ore minerals at low temperatures. However, engineering of novel leaching flowsheets has been h...

Expert consensus regarding standardization of sample preparation for clotting time assays.

Accurate clotting time assay results are vital, as the test is employed to indicate the amount of oral anticoagulant to be prescribed, while it is also used for screening the hemorrhagic and thrombotic diseases. The procedure chosen for preparation of a patient blood sample including centrifugation can contribute to significant differences in the results obtained. Thus, for the purpose of proposing a standardized method to appropriately prepare blood samples prior to assay, the Japanese Society of Laboratory Hematology organized the Working Group for Standardization of Sample Preparation for Clotting Time Assays (WG). Following reviews of previously announced guidelines and original experimental results, consensus was obtained by the WG, with the main findings as follows. (1) The recommended anticoagulant in the blood collection tube is sodium citrate solution at 0.105-0.109M (3.13-3.2%). (2) Whole blood samples should be stored at room temperature (18-25 ˚C) within 1h of collection from the patient. (3) For plasma preparation, centrifugation at 1500 × g should be performed for at least 15min or at 2000 × g for at least 10min at room temperature. (4) After the plasma sample is prepared, it should be stored at room temperature and assayed within 4h.

Base metal citrate pretreatment of complex ores to improve gold and silver leaching with thiourea

A pretreatment to remove and recover base metals present in complex sulfide refractory ores is proposed as a method to improve the extraction of precious metals with thiourea. Sodium citrate solutions at pH 8 and 5 were employed to extract lead and iron, respectively, from two concentrates: one having silver in a primarily galena matrix and the other, with gold associated with pyrite. The pretreatment solutions, containing the base metals, were subjected to electrolysis and pH adjustment, before being recycled back to the pretreatment stage. The results showed that citrate pretreatment successfully extracted lead and some iron, liberating the precious metals for thiourea leaching. The citrate pretreatment solution could be reutilized, after base metal removal, decreasing the reagent and water requirements. In all cases, the citrate pretreatment improved precious metal extraction.

Alginate-Gelatin Microspheres Protect Human Mesenchymal Stem Cells During Deep Cryopreservation

Background: The need for on-demand biological products has been raised during the last decades. To prepare ready-to-use organ-related products, it necessitates a bulk cell reservoir. In this regard, stem cells, especially mesenchymal stem cells, have numerous therapeutic properties in tissue repair. Therefore, the advent of novel cell banking systems is inevitable to maintain cells ready-to-use. Objectives: In the current study, the cryoprotective effects of alginate-gelatin were investigated on human mesenchymal stem cells after seven days. Methods: Mesenchymal stem cells were classified into two groups; the Control and Encapsulated cells. Cells were encapsulated by using the mixture of alginate (1% v/v) and 2% gelatin and 1% CaCl2, a cross-linker, and vitrified in liquid nitrogen in freezing medium containing 10% dimethyl sulfoxide. After seven days, mesenchymal stem cells were thawed and decapsulated by 0.01 M sodium citrate solution. The cell survival rate was monitored by using MTT assay. Flow cytometry analysis of annexin-V/PI was used to determine the number of apoptotic cells. Results: These data showed that encapsulation had a superior effect on maintaining cell viability after the freeze-thaw procedure compared to the control group (P < 0.05). We found a significant decrease in the number of early- and late-stage apoptotic cells in mesenchymal stem cells inside the alginate-gelatin microspheres seven days after deep freezing (P < 0.05). As expected, cell cycle analysis specified the lack of dynamic activity in cells from both groups. Cells at phases S and G2/M reached zero. Conclusions: These findings showed that encapsulation of human mesenchymal stem cells with alginate-gelatin microspheres could reduce deep freeze/thaw insult and decrease the detrimental effect of cryoprotectant compared to non-capsulated cells.

Analytical solutions of citrate–phosphate coupled model of rice (Oryza sativaL.) roots

The citrate secreted by the rice (Oryza sativa L.) roots will promote the absorption of phosphate, and this process is described by the Kirk model. In our work, the Kirk model is divided into citrate sub-model and phosphate sub-model. In the citrate sub-model, we obtain the analytical solution of citrate with the Laplace transform, inverse Laplace transform and convolution theorem. The citrate solution is substituted into the phosphate sub-model, and the analytical solution of phosphate is obtained by the separation variable method. The existence of the solutions can be proved by the comparison test, the Weierstrass M-test and the Abel discriminating method.

Orphan Formulations for Pediatric Use: Development and Stability Control of Two Sildenafil Citrate Solutions for the Treatment of Pulmonary Hypertension

Sildenafil citrate causes vasodilatation, relaxation of the smooth muscle, and reduction of pulmonary arterial pressure. The latter property makes sildenafil citrate efficient for the treatment of cardiovascular diseases, including pulmonary arterial hypertension. Pediatric patients with pulmonary arterial hypertension are more susceptible to errors in drug administration than adults because of a lack of suitable drug dosages. Thus, the purpose of this study was to develop stable (chemically and microbiologically) sildenafil citrate drop liquid formulation, suitable for pediatric patients (including diabetics), ensuring safety during preparation and storing and improving palatability by using milk as a carrier for administration. The significant factors that affect the sildenafil solubility were evaluated by applying a Plackett-Burman design using two levels with six variables. The experiment showed that the type of buffer and glycerin content influenced the sildenafil solubility. The developed formulations proved to be stable for 6months at all three assayed conditions (40± 2°C, 75 ± 5% RH; 25± 2°C, 60 ± 5% RH; and 4 ± 2°C). The microbiological tests fit with the requirement of the pharmacopeia at day 0 and 90 and even more at day 180. Finally, the palatability assay showed that 0.82mL of the formulation containing buffer phosphate, 20% glycerin, and 4mgmL-1 of sildenafil citrate diluted in 4.8mL milk (which fits the medium pediatric dose) presented similar palatability to milk alone, and no precipitate or turbidity was observed. Graphical abstract.

Synthesis of Bi2S3 thin films based on pulse-plating bismuth nanocrystallines and its photoelectrochemical properties.

The solubility of Bi3+ in aqueous solution is an important factor that limits the fabrication of high-quality Bi2S3 thin films. In order to find a low-cost method to manufacture high-quality Bi2S3 thin films, we are reporting the preparation of the Bi2S3 thin films based on pulse-plating method in this paper for the first time. The nano-bismuth particles were obtained by electroplating on fluorine-doped SnO2 (FTO)-coated conducting glass substrates with saturated bismuth potassium citrate solution as the electroplating bath, and then it was put into a muffle furnace to oxidize. Finally, the thin films depositing on FTO glass substrates were put into the thioacetamide solution for vulcanization. In the end, the Bi2S3 thin films were successfully prepared on FTO glass substrates. Different characterization techniques were used to characterize the structure, morphology and photoelectrochemical properties of the prepared thin films. The test results revealed that we used this method to synthesize the high-quality Bi2S3 thin films, thus the Bi2S3 materials synthesized through this method are promising candidates in photoelectrochemical application.

Дослідження антимікробної дії розчину міді і цитрату срібла за ентеробактеріозів бджіл

Дослідження антимікробної дії розчину міді і цитрату срібла за ентеробактеріозів бджіл

Highly transparent, self-healing, injectable and self-adhesive chitosan/polyzwitterion-based double network hydrogel for potential 3D printing wearable strain sensor.

A purely physically crosslinked double network (DN) hydrogel, poly(sulfobetaine-co-acrylic acid)/chitosan-citrate (P(SBMA-co-AAc)/CS-Cit) DN hydrogel, was prepared based on electrostatic interaction and hydrogen bonding between the polymer chains. The hydrogel is highly stretchable, transparent, anti-fatigue, self-adhesive and has good self-healing properties with a self-healing efficiency as high as 95.4%. Furthermore, the resistance of the P(SBMA-co-AAc)/CS-Cit DN hydrogel is sensitive to a wide strain window and the relative resistance shows stable and reliable change during deformation. Herein, the hydrogel was demonstrated as a strain sensor to detect human motions, such as joint bending and swallowing. More excitingly, before ionic crosslinking, the P(SBMA-co-AAc)/CS-Cit composite hydrogel is injectable, thus the P(SBMA-co-AAc)/CS-Cit DN hydrogel sensor can be made into various complex shapes by injecting the P(SBMA-co-AAc)/CS-Cit composite hydrogel into citrate solution, including multilayer structures, exhibiting a great potential for applications as 3D printing strain sensors.

Application of Waste Lemon Extract to Toxic Metal Removal through Gravitational Soil Flushing and Composting Stabilization

The present study aims to investigate the treatment efficiency of soil flushing using waste lemon extract for samples collected from contaminated farmland, in which the copper concentration was measured as 2487 ± 139 mg/kg. The flushing solution, containing 9.9 g/L citric acid, was prepared from the waste lemon extraction process. The soil-flushing treatment using a solution containing commercial citric acids of 10 g/L was also conducted for comparison. Additionally, the collected soil was mixed with crushed waste lemons and the mixture was subjected to a composting process for subsequent stabilization study. After 120-min batch experiments, the desorbed copper concentration for waste lemon-extract experiment was 36.9 mg/L, which was higher than that (28.6 mg/L) for commercial citric solution experiment. The reduction in soil copper concentration (1504 mg/kg) treated by waste lemon-extract flushing was more than that treated by commercial citric solution (1256 mg/kg) at the comparable citric acid concentration. More metals were removed by waste lemon-extract flushing. This is because the waste lemon-extract solution contains additional co-dissolved organic substances with a longer flushing time, which allows more exchange reactions between adsorbed metals and flushing solution. For the treatment with waste lemon extract, the soil pH values were 4.56, 5.70 and 6.29 before, after flushing and after compost treatment, respectively. The observed variation in soil pH also showed that waste lemon extract might be a better flushing agent, while flushing with commercial citric solution decreased the pH in the soil environment. The plant copper availability dropped from 677 mg/kg to 156 mg/kg after waste lemon-extract flushing and stabilization with composted waste lemon. Therefore, the use of waste lemon extract for soil flushing not only removed toxic metals from the soil but also prevented the occurrence of soil acidification, an often-observed phenomenon using an acidic solution in conventional soil flushing. After soil flushing, the application of composted waste lemon could stabilize the toxic metals and increase the pH to a range suitable for plant growth.

Cryopreservation of spermatozoa of indigenous stinging catfish, Heteropneustes fossilis (Bloch) for ex-situ conservation

An experiment was conducted to develop cryopreservation protocol for spermatozoa of stinging catfish, Heteropneustes fossilis and to use the cryopreserved sperm in its breeding trials. The activation of sperm motility at various concentrations of NaCl solution was tested and complete activation and inhibition of sperm were obtained at 0.4% and 0.9% to 1% NaCl solution respectively. In toxicity test, sperms were incubated with DMSO, methanol and ethanol at 5, 10, and 15% concentrations where DMSO and methanol produced better motility at 5 and 10% concentration with Alsever’s solution and egg-yolk citrate at 5 and- 10 min incubation period. Three extenders- Alsever’s solution, egg-yolk citrate and Ginsburg Fish Ringer solution and three cryoprotectants- DMSO, methanol and ethanol were used for cryopreservation of sperm, and among the diluents, Alsever’s solution with 10% DMSO showed best performance producing 77.50±3.22% post-thaw motility. On the other hand, egg-yolk citrate and Ginsburg Fish Ringer solution along with 10% DMSO produced 63.75±2.39% and 62.50±3.22% post-thaw motility, respectively. Sperm preserved with Alsever’s solution plus 10% DMSO produced 52.5±3.34% and 38.0±2.39%fertilization and hatching, and those preserved with Alsever’s solution plus 10% methanol produced 46.9±3.11% and 32.7±2.70% fertilization and hatching respectively. The fry produced using cryopreserved and fresh sperm grew well and no significant difference (p>0.05) was found between two groups.

Karakterisasi Sifat Fisikokimia, Sensori, Dan Fungsional Nasi Instan Dari Beras Amilosa Rendah

<p>Gaya hidup masyarakat di zaman modern dituntut untuk bergerak cepat termasuk dalam menyiapkan makanan. Oleh karena itu, perlu dicari alternatif proses untuk mempercepat pengolahan beras dengan tetap mempertahankan nilai gizinya. Beras amilosa rendah memerlukan waktu pemasakan yang cepat dengan tekstur yang pulen sehingga cocok digunakan sebagai bahan baku nasi instan. Tujuan dari penelitian ini adalah untuk mempelajari karakteristik fisikokimia, sensori, dan fungsionalnya nasi instan dari beras amilosa rendah. Bahan baku yang digunakan adalah beras Sintanur. Rancangan penelitian yang digunakan adalah Rancangan Acak Lengkap pola faktorial dengan perlakuan suhu pembekuan (-4oC dan -20oC) dan waktu pembekuan (12, 18, dan 24 jam), diulang empat kali. Proses produksi nasi instan menggunakan beras kadar amilosa rendah terdiri dari perendaman dalam larutan natrium sitrat 5% (1:2), pencucian, pengaronan, pemasakan menggunakan rice cooker, pendinginan pada suhu -20oC selama 24 jam, thawing, dan pengeringan. Hasil analisa ragam (ANOVA) menunjukkan bahwa suhu pembekuan, waktu pembekuan, dan interaksi keduanya berpengaruh nyata terhadap karakteristik fisikokimia dan fungsional. Nasi instan memiliki karakteristik waktu rehidrasi 3,19 menit, densitas kamba 0,50 g/ml, rendemen 96,80%, daya serap air 48,73% dan volume pengembangan 154,99%. Nasi instan mengandung kadar air 12,39%, kadar abu 0,67% (bk), kadar lemak 0,18% (bk), kadar protein 0,88% (bk), kadar karbohidrat 90,28% (bk), kadar amilosa 17,28%, dan daya cerna pati 62,37%. Hasil uji sensori menunjukkan bahwa berdasarkan uji kruskal-wallis (p>5%) panelis menyukai warna, rasa, tekstur, aroma, dan penampakan nasi instan pada perlakuan pembekuan suhu -20oC selama 24 jam.</p><p><strong><br /></strong></p><p><strong>Characterization of Physicochemical, sensory, and fungtional Properties of instant rice from low amylose rice.</strong></p><p>In the modern lifestyle people are required to move quickly, including in preparing food. Therefore, alternative processes should be sought to accelerate rice processing while maintaining its nutritional value. This research aimed to produce instant rice using low amylose content with their physicochemical, sensory, and functional characteristics. Raw material used was Sintanur rice. The experiment was conducted in complete randomized design of factorial with treatments of freezing temperature (-20 and -4<sup>o</sup>C) and duration (12, 18, and 24 hour), with four replications. The results of analysis of variance (ANOVA) showed that between freezing temperature and duration were significantly different of their physicochemical and functional characteristics (p<0.05). Instant rice production process using low amylose rice consist of soaking in 5% sodium citrate solution (1: 2), washing, staining, cooking using a rice cooker, freezing at -20<sup>o</sup>C for 24 hours, thawing, and drying. Characteristics of instant rice produced were rehydration time of 3.19 minutes, bulk density of 0,50 g/ml, yield of 96,80%, water absorption of 48,73%, and volume expansion of 154,99%. This product contained of 12,39% moisture, 0,67% ash (db), 0,18% fat (db), 0,88% protein (db), 90,28% carbohydrate (db), 17,28 amylose, and 62,37% starch digestibility. Sensory test results showed that the panelists liked the color, taste, texture, aroma, and appearance of instant rice.</p>

Calorie provision from citrate anticoagulation in continuous renal replacement therapy in critical care.

Citrate is used as a regional anticoagulant for continuous veno-venous haemofiltration and provides 0.59 kcal/mmol. Previous studies hypothesised continuous veno-venous haemofiltration can provide 200-1300 kcal/day dependent on the anticoagulant and replacement solutions used. The aim of this study was to calculate the calorie load from citrate in our patient group. An equation derived from a paper by Oudemans-van Straaten was used to estimate calorie provision from citrate. Citrate calorie load was defined as the difference between the citrate in the filter circuit and the removal by continuous veno-venous haemofiltration. Clinical data were recorded on 20 consecutive patients admitted to intensive care unit and commenced on citrate continuous veno-venous haemofiltration using prismacitrate 18/0 by Gambro, a tri-sodium citrate solution. Clinical data recorded included patient demographics, filter settings including blood flow, filtration factor, citrate dose and time on filtration daily. A total of 20 critically ill patients received continuous veno-venous haemofiltration for treatment of a new acute kidney injury, mean age 66 years, 65% male. Mean duration of continuous veno-venous haemofiltration was 3.7 days. Mean daily time on filtration was 20 h/day. Mean filtration fraction, citrate dose and blood flow were 30%, 3 mmol/L and 123 ml/min, respectively. Our calculation showed that a mean of 9.5 ± 1.7 cal/h were provided from citrate with a mean daily calorie load of 196 ± 69 kcal. Continuous veno-venous haemofiltration with tri-sodium citrate provided an additional 196 ± 69 kcal/day. The calorie load from citrate continuous veno-venous haemofiltration should be calculated regularly as changes in filter settings, in particular citrate dose and blood flow can have a significant impact on calorie provision.

Leaching of Rare Earth Elements from Central Appalachian Coal Seam Underclays

Rare earth elements (REE) are necessary for advanced technological and energy applications. To support the emerging need, it is necessary to identify new domestic sources of REE and technologies to separate and recover saleable REE product in a safe and economical manner. Underclay rock associated with Central Appalachian coal seams and prevalent in coal utilization waste products is an alternative source of REE to hard rock ores that are mainly composed of highly refractory REE-bearing minerals. This study utilizes a suite of analytical techniques and benchtop leaching tests to characterize the properties and leachability of the coal seam underclays sampled. Laboratory bench-top and flow-through reactor leaching experiments were conducted on underclay rock powders to produce a pregnant leach solution (PLS) that has relatively low concentrations of gangue elements Al, Si, Fe, and Th and is amenable to further processing steps to recover and produce purified REE product. The leaching method described here uses a chelating agent, the citrate anion, to solubilize elements that are adsorbed, or weakly bonded to the surface of clay minerals or other mineral solid phases in the rock. The citrate PLS produced from leaching specific underclay powders contains relatively higher concentrations of REE and lower concentrations of gangue elements compared to PLS produced from sequential digestion using ammonium sulfate and mineral acids. Citrate solution leaching of underclay produces a PLS with lower concentrations of gangue elements and higher concentrations of REE than achieved with hydrochloric acid or sulfuric acid. The results provide a preliminary assessment of the types of REE-bearing minerals and potential leachability of coal seam underclays from the Central Appalachian basin.

Ionically Conductive Hydrogel with Fast Self‐Recovery and Low Residual Strain as Strain and Pressure Sensors

Hydrogel-based sensors have attracted enormous interest due to their broad applications in wearable devices. However, existing hydrogel-based sensors cannot integrate satisfying mechanical performances with excellent conductivity to meet the requirements for practical application. Herein, an ionically conductive hydrogel with high strength, fast self-recovery, and low residual strain is constructed through a facile soaking strategy. The proposed ionically conductive double network hydrogel is achieved by combining chemically crosslinked polyacrylamide and physically crosslinked gelatin network followed by sodium citrate solution immersing. The obtained hydrogel has a tensile strength of 1.66 MPa and an elongation of 849%. The ionically conductive hydrogels can be utilized as both strain and pressure sensors with high sensitivity. Moreover, they can be used as ionic skin to monitor various human movements precisely, demonstrating their promising potential in wearable devices and flexible electronics.

Fe2+ Ions Alleviate the Symptom of Citrus Greening Disease.

Citrus greening (CG) is among the most devastating citrus diseases worldwide. CG-infected trees exhibit interveinal chlorotic leaves due to iron (Fe) deficiency derived from CG; thus, Fe content is lower in infected leaves than in healthy leaves. In this study, we demonstrated that the foliar application of Fe2+ relieves the symptom of CG infection in citrus trees. We applied Fe2+ and citrate to the leaves of infected rough lemon plants. Following this treatment, a reduction in the number of yellow symptomatic leaves was observed, and their growth was restored. Using chlorophyll content as an index, we screened for effective Fe complexes and found that a high ratio of citrate to Fe2+ in the applied solution led to effects against CG in Shikuwasa trees. A high proportion of Fe2+ to total Fe was another key factor explaining the effectiveness of the solution in CG infection, indicating the importance of Fe2+ absorption into plant cells. We confirmed the proportion of Fe2+ to total Fe through the high correlation of reflectometry data via a triazine reaction and X-ray absorption fine structure analysis. These results demonstrate that the foliar application of a high-Fe2+ citrate solution can restore the growth of CG diseased trees.

P1096SAFETY AND EFFICACY OF A NEW SIMPLIFIED REGIONAL CITRATE ANTICOAGULATION PROTOCOL FOR SUSTAINED LOW EFFICIENCY DIALYSIS FOCUSED ON PREVENTION OF RRT-INDUCED HYPOPHOSPHATEMIA IN CRITICALLY ILL RENAL PATIENTS

Abstract Background and Aims Sustained-Low Efficiency Dialysis (SLED) is a hybrid Renal Replacement Therapy (RRT) increasingly used in critically ill patients with Acute Kidney Injury (AKI). Usually lasting 8-12 hours, this modality combines several advantages of both intermittent and continuous RRT (CRRT). Regional citrate anticoagulation (RCA) represents the most adequate anticoagulation strategy to avoid the extracorporeal circuit clotting. Hypophosphatemia (serum phosphorus, s-P, levels ≤ 2.5 mg/dl) is a common electrolyte disorder in critically ills, with an increased incidence in course of prolonged RRTs, especially when standard dialysis/replacement solutions and highly intensive modalities are employed. Given the potentially negative impact of hypophosphatemia on patients’ outcomes, strategies aimed at preventing its onset should be appropriately implemented. This pilot study is aimed at evaluation of safety and efficacy of a simplified RCA protocol for SLED, based on the combination of a low-concentrated citrate solution with a phosphate-containing solution. Methods a prospective observational study was conducted on critically ill patients with AKI requiring RRT or End Stage Renal Disease (ESRD) previously on RRT admitted to our renal Intensive Care Unit (ICU). SLED was performed by the Prismax system (Baxter) and polyacrylonitrile AN69 haemofilters (ST 150, 1.5 m2, Baxter). 8-hours SLED sessions were prescribed, in the SLED-f variant, by using a 18 mmol/l pre-dilution trisodium citrate solution (Regiocit 18/0, Baxter) combined with a phosphate-containing solution acting as dialysate (Ca2+ 0, HPO42- 1, Mg2+ 0.75, HCO3- 22 mmol/l; Biphozyl, Baxter) and a standard RRT solution acting as post-dilution replacement fluid (Prismasol 4, Baxter). Calcium chloride (CaCl 10%) was infused in a separate central venous line to maintain the systemic Ca2+ (s-Ca2+) within a normal range. Each patient underwent three consecutive daily SLED sessions. The activated coagulation time (ACT), acid–base parameters, s-Ca2+ and potassium were measured at SLED start and every 2 h. Phosphorus and magnesium losses with RRT were replaced, when needed, with sodium glycerophosphate pentahydrate (GlycophosTM 20 mmol/20 ml, Fresenius Kabi Norge AS, Halden, Norvegia) and magnesium sulphate. Results a total of 60 SLED-f sessions were performed in 20 ICU patients. At ICU admission, the average APACHE II score was 21.8 and half of patients were mechanically ventilated. Many of them showed hemodynamic instability and AKI was oliguric in 90% of cases. No premature interruptions for irreversible filter clotting occurred and the prescribed dialysis dose was delivered in 95% of cases. No statistically significant differences were observed between systemic ACT at SLED start and during RRT sessions, and no major hemorrhagic events were observed. Regarding RCA, no clinically relevant episode of hypo or hypercalcemia was observed, and calcium infusion rate remained constant in course of treatments. Acid-base status was effectively maintained during the entire period of treatment and no episodes of clinically relevant metabolic acidosis or alkalosis were registered. The analysis of the main laboratory variables at SLED start, in course and after 24 h of treatment did not show statistically significant differences. Regardless of starting values, s-P and s-Mg were progressively corrected and maintained within the normality range, limiting the need for exogenous supplementations. Conclusions These preliminary data suggest that our simplified RCA protocol for SLED, combining a low-citrate solution with a phosphate-containing solution, is safe and efficacious allowing to optimizing acid-base balance and to preventing RRT-related hypophosphatemia.

P1074SIMPLIED REGIONAL CITRATE ANTICOULATION USING A CALCIUM-CONTAINING REPLACEMENT SOLUTION FOR RENAL REPLACEMENT THERAPY: A RANDOMIZED CONTROLLED CLINICAL TRIAL

Abstract Background and Aims A simplified protocol for Regional citrate anticoagulation (RCA) using a commercial calcium-containing replacement solution, without a continuous calcium infusion, is more efficient to be used in continuous renal replacement therapy (CRRT). We aim to design a randomized prospective pilot trial to compare the safety and efficacy between calcium-free and calcium-containing replacement solution in CRRT with RCA. Method Of the 59 patients who requiring CRRT and being treated with RCA-based continuous venovenous hemodiafiltration (CVVHDF) enrolled, 31 patients were randomized to calcium-containing group and 28 to calcium-free replacement solution group. Primary endpoints were filters lifespan. Secondary endpoints were mortality, kidney function recovery and severe complications rates. Time spent on fluids preparation before CRRT and the amount of 4% trisodium citrate solution pumped during CRRT were recorded. Serum and effluent citrate and calcium concentration during CVVHDF were measured during CRRT. Results Filters lifespan were superior for calcium-containing group (mean 58.06 versus 47.12 hours, P=0.05). Mortality and renal outcome were comparable between groups during hospitalization: 10/31 (33.26%) of calcium-containing group patients died versus 13/28 (46.43%) of calcium-free group patients, and 16/31 (51.61%) of calcium-containing group patients had kidney function recovery versus 15/28 (53.57%) of calcium-containing group (P = 0.265). Only 5 patients showed the symptoms and signs of hypocalcemia or citrate toxicity in this study. The mean CRRT preparation time in calcium-containing group: 25.5 minutes, was significantly shorter than calcium-free group: 43.7 minutes (p<0.001). The serum and effluent calcium concentration was slightly lower in calcium-containing group during CRRT. While, the mean 4% trisodium citrate solution infusion rate was similar between groups (161.5 mL/h versus 157.4 mL/h, P=0.376). Conclusion Patients treated with calcium-containing or calcium-free replacement solution have similar clinical outcomes. Since the calcium-containing replacement solution based RCA has longer filter lifespan and obviates the need for a separate venous catheter and intravenous calcium preparation for continuous intravenous calcium infusion, it is more efficient to be used in clinical practice and superior to the calcium-free replacement solution.

P0120FEATURES OF ULTRASTRUCTURAL CHANGES IN KIDNEY TISSUE IN THE PATIENTS WHO HAVE PASSED AWAY AS A RESULT OF SEPSIS

Abstract Background and Aims It is believed that septicemia and septicopyemia can lead to functional failure of many organs, including the kidneys. In this regard, it is important to study the morphological features of ultrastructural changes in kidney tissue. Method Structural changes in renal tissue of 30 patients who died as a result of sepsis were investigated by electron-microscopy. The burial was carried out at an early stage (1-6 hours after death). The sections obtained for ultrasonic examination were examined on “James 100 S ” electron microscope after contrasting with uranyl acetate and lead citrate solution. Results An ultrastructural study of the cells of the cortical and medial layers of the kidneys revealed that there are changes in extracellular contacts and cell fragmentation as a result of lysis of the cytoplasmic membrane of cells. The integrity of the basal membrane of epithelial cells of the proximal and distal tubules are preserved. However, the basal layer did not have a homogeneous structure, intersected and transparent in certain areas. Numerous vacuoles, lipid supplements and fragments of lysed intracellular proteins in the cytoplasm have been identified in the cytoplasm of cells. Most of the nucleus was in the collapse phase. The lumen of tubules is narrow and most of the microvilli of the brush border are destructed. It was revealed that in sepsis renal failure and severe destructive changes and the formation of necrosis sites in the structural elements of the nephron as a result of bacterial toxins were mainly observed in areas where bacteria were localized. Conclusion Abnormalities of podocytes, of endothelial cells, disruption of the basal membrane layers as a result of abnormal damage of organelles especially mitochondria, changes of proximal and distal tubules may be caused by severe renal failure due to sepsis.

Synthesis of highly conductive hydrogel with high strength and super toughness

The manufacture of high performance flexible electronic materials remains a huge challenge. Herein, a facile strategy was developed for the preparation of conductive hydrogel with high strength and super toughness using green biomass lignin and biodegradable poly(vinyl alcohol) (PVA) as raw materials. The enzymatic hydrolysis lignin (DEL) was introduced into the PVA hydrogel to form the nanophase separation structure and promote the adsorption of silver ions, which significantly contributed to the improvements in mechanical and conductive properties of the composite hydrogel. The silver ions in the hydrogel were reduced to generate the silver nanoparticles (AgNPs) by immersing in the green reducing agent of sodium citrate solution. The silver nanoparticles in the hydrogel network significantly enhanced the hydrogel, endowing the composite hydrogel Ag0@DEL with particularly large toughness of 78.1 MJ/m3, powerful tensile strength up to 13.3 MPa and high strain at break up to 1220%. The composite hydrogel Ag0@DEL also exhibited good electrical conductivity of about 1.0 S/m and performed high strain sensitivity and stable response to the deformation of stretching, compression and twist.