Objective The purity and activity of islets will greatly affect the outcome of xenotransplantation therapy of type 1 diabetes mell itus. To set up an improved method of the isolation and purification of rat islets, which can obtain highpurity,high-yield, and high-viabil ity islets. Methods Ten healthy and adult male SD rats, weighing 250-300 g were used asorgan donors. Collagenase V was perfused into pancreas via pancreatic duct. Pancreas was digested with collagenase in water bath at 38℃ about 15 minutes, islet purification was performed using two techniques: with Ficoll 400 density gradient (group A), and Ficoll-Paque? PLUS (group B). Dithizone (DTZ) was util ized for identifying islets, counting islets equivalent quantity (IEQ) and islets’ purity. Trypan blue staining was used to detect the viabil ity of islets. Islets of group B was encapsulated with alginate/poly-L-lysine/alginate (APA). Islets function of microencapsulated and nonmicroencapsulated was evaluated by the insul in release test. Results DTZ staining showed that islets shape were round, ell ipse and irregular with a clear edge and a diameter range of 50-300 μm. The IEQ values were 338.04 ± 76.61 and 834.80 ± 54.00 in groups A and B, respectively, showing significant difference (P lt; 0.05). The purities were 88.31% ± 2.67% and 95.63% ± 1.96% in groups A and B, respectively, showing no significant difference (P gt; 0.05). The activities of islets were 67.40% ± 5.15% and 86.05% ± 2.52% in groups A and B, showing significant difference (P lt; 0.05). Islet APA microcapsules had round shape, unified size, and its diameter was between 1.5 and 2.0 mm. Each microcapsule was encapsulated of 1 to 3 islets. The result of insul in release assay was that the concentrations of insul in secretion with islets of microencapsulated and nonmicroencapsulated were (5.53 ± 1.64) ng/ mL and (4.76 ± 0.26) ng/mL in low glucose, and its concentrations of insul in secretion in high glucose were (11.95 ± 2.07) ng/ mL and (14.34 ± 3.18) ng/mL. Stimulated insul in secretion in high glucose was 2 times more than that in low glucose (P lt; 0.05), but there was no significant difference (P gt; 0.05) in the stimulation index between group A (2.16 ± 0.30) and group B (3.01 ± 0.59). Conclusion The method of islets isolation and purification using Ficoll-Paque? PLUS own the virtues of more convenient, high islet yield, and high islet purity. Both microencapsulated and nonmicroencapsulated islets show high-viabil ity while culture in vitro.
In this research a strain of isolated Pseudomonas alcaligenes which causes degradation of dexamethasone was acclimated further and its proteins of every position in the bacterium were separated by the osmotic shock method. The separated intracellular proteins which had the highest enzyme activity were extracted by the salting out with ammonium sulfate and were purified with the cation exchange chromatography and gel chromatography. The purified proteins which was active to cause degradation of dexamethasone had been detected were cut with enzyme and were analyzed with mass spectrometry. The results showed that the degradation rate to dexamethasone by acclimated Pseudomonas alcaligenes were increased from 23.63% to 52.84%. The degrading enzymes were located mainly in the intracellular of the bacteria and its molecular weight was about 41 kD. The specific activity of the purified degrading enzymes were achieved to 1.02 U·mg-1. Its 5-peptide amino acid sequences were consistent with some sequences of the isovaleryl-CoA dehydrogenase. The protein enzyme may be a new kind degrading enzyme of steroidal compounds. Our experimental results provided new strategies for cleanup of dexamethasone in water environment with microbial bioremediation technique.
Blood purification is not only an effective treatment for patients with acute and chronic renal failure, but also plays an important role in the rescue of various critically ill patients. The current blood purification devices is relatively bulky and not suitable for use in daily life and disaster rescue sites. Portable blood purification devices can be divided into portable artificial kidney, wearable artificial kidney, implantable artificial kidneys and mobile continuous renal replacement therapy machine, which have not yet been widely applied in clinical practice. In recent years, with the advancement of materials science and computer science, efficient regeneration of dialysate and intelligent operation of equipment have become possible, and portable blood purification devices is also expected to experience rapid development. This article briefly reviews the development history and future research directions of portable blood purification devices.
Objective To investigate the value of continuous blood purification （CBP）in early treatment of patients with ARDSexp （ARDS caused by extrapulmonary causes），especially in reducing inflammation mediators and extravascular lung water （EVLW）.Methods According the hospital admission sequence，the patients with APACHEⅡ scores from 15 to 20 and PaO2/FiO2 from 100 to 200 were recruited.The ARDSexp patients were divide into an intervention group treated with CBP （Mode：CVVHDF，rate of displacement liquid and dialysate：1.5 L/h，rate of blood：100-200 mL/h，and the time of CBP：72 hours），and a control group without CBP treatment. The NICO and PICCO monitoring data and the survival rates were recorded and analyzed using the SPSS software. Results The mortality rate of the intervention group was lower than that of the control group （6.3% vs. 36.8%，P=0.032）. In the 72 h monitoring dada of NICO and PICCO，the time of improving PCBF，Pm，Cdyn，VCO2，MValv，Pm，PIP，Raw，RSBI，Vd/Vt，and PaO2/FiO2 of the intervention group was severer than those in the control group，and the severety was also more than that of control group which was was significantly different at 72 h（Plt;0.05）. In the PICCO data，the time of decreasing EVWL and PVPI was shorter than the control group，and the decreasing extent was more than the control group，with significant difference at 72 h. But the changes of Apm，CI，and CVP were not significant （Pgt;0.05）. Conclusions In treatment of ARDSexp patients，CBP therapy can induce the PCBC and EVLW，improve pulmonary compliance and MValv，and reduce the mortality rate，while doesn’t influence heart function and the stability of circulation.
bjective To separate the SO-Rb50 cells antigen corresponding to the monoclonal antibody of anti-retinoblastoma. Methods The antigen corresponding to the monoclonal antibody of anti-retinoblastoma was separated elementarily by ion-exchange chromatography, and was identified by dot-blotting using the monoclonal antibody of anti-retinoblastoma. The target protein band of the antigen was separated in light of sodium dodecyl sulfate-polyacrylamide gelelectrophoresis. Results A special unmixed band of SO-Rb50 cells antigen was separated with the relative molecular weight of 83×103.Conclusion The antigen corresponding to the monoclonal antibody of anti-retinoblastoma could be separated from SO-Rb50cells.(Chin J Ocul Fundus Dis，2003，19：152-155)
Patients with severe acute kidney injury (AKI) often need renal replacement therapy (RRT）with a high morbidity and mortality. For patients with chronic renal failure, the aim of blood purification is renal replacement; but for patients with AKI, although customarily called RRT, the aim of blood purification is not “renal replacement”, but extracorporeal “renal support and protection”, that is, supporting and protecting temporally failed kidney, removing damage factors, avoiding renal reinjury and looking forward to restore renal function. This article provides a detailed explanation of the differences between renal replacement and renal support from the perspective of organ protection, as well as the key links of RRT and extracorporeal multiple organ support for patients with severe AKI.
After comparative interpretation of the essentials and highlights of the expert recommendations based on European experience published in 2019 and the expert recommendations based on Asia Pacific experience published in 2021, this article summarizes the core principles of adsorptive hemofiltration for sepsis in following aspects, including patient selection, laboratory index, and key factors in the implementation of treatment (covering initiation timing and duration, choice of anticoagulant mode, discontinuation, etc) combined with the experience in West China Hospital of Sichuan University as well, to provide references for sepsis management with adsorptive hemofiltration in clinical practice.
To obtain recombinant human β2-microglobulin (rhβ2M) with properties of good solubility and high purity from E.coli, prokaryotic expression conditions were optimized and protein purification was performed in this study. After testing the effect of different IPTG concentrations, temperatures and induction times on the production of rhβ2M, the optimum expression conditions were determined, i.e. joining IPTG to final concentration being 0.8 mmol/L and inducing time 6 h and at temperature of 25℃. Under the optimum induction conditions, the ratio of soluble rhβ2M to soluble bacterial protein was 63.7%. After purified by Ni Sepharose 6 Fast Flow, the purity of rhβ2M achieved a greater value of 95%. Western blot analysis revealed that rhβ2M possessed the antigen property that specifically interacted with anti-β2M antibody.
In this article, the first time use of continuous veno-venous hemofiltration(CVVH) combined with toxic absorption for the treatment of a crush syndrome patient injured in earthquake is described. Correct therapeutic regimen, close observation and prescription condition are crucial for the success of management. The evidence for the application of this method is also discussed in detail.
Objective To review the general approaches in isolation and purification of pancreatic islets and progress in several aspects. Methods The latest l iterature concerning acquisition of pancreatic islets was reviewed and analyzed interms of the choice of pancreatic islet donors, the digestion and isolation of pancreas, the purification of islet and the assay of outcome. Results The profile of the isolation and purification depends on the selection of reagents and methods of operation in every step and l inkup between every step. Conclusion Pancreatic islet transplantation is the most effective method to treat type 1 diabetes, the problem of inadequate sources of pancreatic islets could be resolved by the optimal process and the establ ishment of standardized operation.
