OBJECTIVE: To investigate the efficacy of a novel artificial perfusate based on oxygen-carrying perfluoronaphthalene-albumin nanoparticles in normothermic machine perfusion (NMP) for preservation of porcine liver donation after cardiac death. METHODS: Artificial perfusate with perfluoronaphthalene-albumin nanoparticles was prepared at 5% albumin (w/v) and its oxygen carrying capacity was calculated. The livers of 16 Landrace pigs were isolated after 1 h of warm ischemia, and then they were divided into 4 groups and preserved continuously for 24 h with different preservation methods: cold preservation with UW solution (SCS group), NMP preservation by whole blood (blood NMP group), NMP preservation by artificial perfusate without nanoparticles (non-nanoparticles NMP group) and NMP preservation by artificial perfusate containing nanoparticles (nanoparticles NMP group). Hemodynamics, tissue metabolism, biochemical indices of perfusate and bile were monitored every 4 h after the beginning of NMP. Liver tissue samples were collected for histological examination (HE and TUNEL staining) before preservation, 12 h and 24 h after preservation. RESULTS: The oxygen carrying capacity of nanoparticles in 100 mL artificial perfusate was 6.94 μL/mmHg (1 mmHg=0.133 kPa). The hepatic artery and portal vein resistance of nanoparticles NMP group and blood NMP group remained stable during perfusion, and the vascular resistance of nanoparticles NMP group was lower than that of blood NMP group. The concentration of lactic acid in the perfusate decreased to the normal range within 8 h in both nanoparticles NMP group and blood NMP group. There were no significant differences in accumulated bile production, alanine aminotransferase and aspartate aminotransferase in perfusate between nanoparticles NMP group and blood NMP group (all P>0.05). After 24 h perfusion, the histological Suzuki score in blood NMP group and nanoparticles NMP group was lower than that in SCS group and non-nanoparticles NMP group (all P<0.05), and the quantities of TUNEL staining positive cells in blood NMP group and non-nanoparticles NMP group was higher than those in nanoparticles NMP group and SCS group 12 h and 24 h after preservation (all P<0.05). CONCLUSION Artificial perfusate based on oxygen-carrying nanoparticles can meet the oxygen supply requirements of porcine livers donation after cardiac death during NMP preservation, and it may has superiorities in improving tissue microcirculation and alleviating ischemia-reperfusion injury.
Swine ; Animals ; Liver Transplantation ; Organ Preservation ; Liver ; Perfusion ; Death ; Oxygen/metabolism*

Humans ; Vitrification ; Consensus ; Oocytes ; Fertilization in Vitro ; Cryopreservation

Bioactive glass (BG) has been widely used in the preparation of artificial bone scaffolds due to its excellent biological properties and non-cytotoxicity, which can promote bone and soft tissue regeneration. However, due to the brittleness, poor mechanical strength, easy agglomeration and uncontrollable structure of glass material, its application in various fields is limited. In this regard, most current researches mainly focus on mixing BG with organic or inorganic materials by freeze-drying method, sol-gel method, etc., to improve its mechanical properties and brittleness, so as to increase its clinical application and expand its application field. This review introduces the combination of BG with natural organic materials, metallic materials and non-metallic materials, and demonstrates the latest technology and future prospects of BG composite materials through the development of scaffolds, injectable fillers, membranes, hydrogels and coatings. The previous studies show that the addition of BG improves the mechanical properties, biological activity and regeneration potential of the composites, and broadens the application of BG in the field of bone tissue engineering. By reviewing the recent BG researches on bone regeneration, the research potential of new materials is demonstrated, in order to provide a reference for future related research.
Bone Regeneration ; Bone and Bones ; Freeze Drying ; Glass ; Hydrogels

Ultra-rapid cooling and rewarming rate is a critical technical approach to achieve ice-free cells during the freezing and melting process. A set of ultra-rapid solid surface freeze-thaw visualization system was developed based on a sapphire flim, and experiments on droplet freeze-thaw were carried out under different cryoprotectant components, volumes and laser energies. The results showed that the cooling rate of 1 μL mixed cryoprotectant [1.5 mol/L propylene glycol (PG) + 1.5 mol/L ethylene glycol (EG) + 0.5 mol/L trehalose (TRE)] could be 9.2×10 ³ °C/min. The volume range of 1-8 μL droplets could be vitrified. After comparing the proportions of multiple cryoprotectants, the combination of equal proportion mixed permeability protectant and trehalose had the best vitrification freezing effect and more uniform crystallization characteristics. During the rewarming operation, the heating curve of glassy droplets containing gold nanoparticles was measured for the first time under the action of 400-1 200 W laser power, and the rewarming rate was up to the order of 10 ⁶ °C/min. According to the droplet images of different power rewarming processes, the laser power range for ice-free rewarming with micron-level resolution was clarified to be 1 400-1 600 W. The work of this paper simultaneously realizes the ultra-high-speed temperature ramp-up, transient visual observation and temperature measurement of droplets, providing technical means for judging the ice free droplets during the freeze-thaw process. It is conducive to promoting the development of ultra-rapid freeze-thaw technology for biological cells and tissues.
Freezing ; Vitrification ; Cryopreservation/methods* ; Trehalose ; Gold ; Rewarming ; Metal Nanoparticles ; Cryoprotective Agents ; Lasers

Cryopreservation of rare testicular-retrieved spermatozoa for intracytoplasmic sperm injection (ICSI) in patients with severe oligozoospermia and azoospermia remains a major challenge in clinical practice. This study evaluated the Cryopiece system as a potential technique to cryopreserve rare human spermatozoa for ICSI. Small numbers of ejaculated (24 patients) and testicular (13 patients) spermatozoa were cryopreserved using the Cryopiece system. The total number of recovered spermatozoa and motility were assessed after thawing. Thirty-seven couples underwent ICSI using spermatozoa cryopreserved by the Cryopiece system, and ICSI outcomes (rates of fertilization, embryo cleavage, and clinical pregnancy) were evaluated. The average sperm post-thaw retrieval rate was 79.1%, and motility was 29.7%. Ejaculated spermatozoa had a higher post-thaw motility (32.5%) than testicular spermatozoa (21.8%; P = 0.005). ICSI achieved a fertilization rate of 61.9%, embryo cleavage rate of 84.6%, and clinical pregnancy rate of 43.3%. The ICSI outcomes in the ejaculated and testicular frozen-thawed spermatozoa were similar. Assisted oocyte activation (AOA) after ICSI with motile (72.1%) or immotile (71.9%) spermatozoa resulted in a significantly higher fertilization rate than that when using motile spermatozoa without AOA (52.0%; P = 0.005). However, AOA did not enhance the clinical pregnancy rate (55.6% or 40.0% vs 35.3%; P = 0.703). The Cryopiece system is simple and useful for the cryopreservation of small numbers of ejaculated or testicular spermatozoa for ICSI in patients with severe oligozoospermia or nonobstructive azoospermia.
Azoospermia ; Cryopreservation ; Female ; Humans ; Male ; Oligospermia ; Pregnancy ; Pregnancy Rate ; Retrospective Studies ; Semen ; Sperm Injections, Intracytoplasmic ; Sperm Motility ; Spermatozoa ; Testis

In the 1960s, sperm cryopreservation was developed as a method to preserve fertility. Currently, techniques for the cryopreservation of human spermatozoa have been widely used in assisted reproduction. However, although sperm cryobiology has made notable achievements, the optimal method for the recovery of viable spermatozoa after cryopreservation remains elusive. Postthawing sperm quality can be affected by cryoprotectants, ice formation, storage conditions, and osmotic stress during the freezing process. This review discusses recent advances in different cryopreservation techniques, cryoprotectants, and freezing and thawing methods during cryopreservation and new indications for the use of cryopreserved spermatozoa.
Humans ; Male ; Semen Preservation/methods* ; Sperm Motility ; Semen ; Cryopreservation/methods* ; Spermatozoa ; Cryoprotective Agents/pharmacology*

Cryopreservation ; Humans ; Male ; Methanol ; Nitrogen ; Papillomavirus Infections ; Pilot Projects ; Semen Preservation ; Spermatozoa

OBJECTIVE: To investigate the anti-oxidative effect of ethyl pyruvate (EP) and taurine (TAU) on the quality of red blood cells stored at 4±2 ℃, hemolysis, energy metabolism and lipid peroxidation of the red blood cells in the preservation solution were studied at different intervals. METHODS: At 4±2 ℃, the deleukocyte red blood cells were stored in the citrate-phosphate-dextrosesaline-adenine-1 (CPDA-1) preservation (control group), preservation solution with EP (EP-AS), and TAU (TAU-AS) for long-term preservation. The enzyme-linked immunoassay and automatic blood cell analyzer were used to detect hemolysis and erythrocyte parameters. Adenine nucleoside triphosphate (ATP), glycerol 2,3-diphosphate (2,3-DPG) and malondialdehyde (MDA) kits were used to test the ATP, 2,3-DPG and MDA concentration. RESULTS: During the preservation, the rate of red blood cell hemolysis in EP-AS and TAU-AS groups were significantly lower than that in CPDA-1 group (P<0.01). The MCV of EP-AS group was increased with the preservation time (r=0.71), while the MCV of the TAU-AS group was significantly lower than that in the other two groups (P<0.05). The concentration of ATP and MDA in EP-AS and TAU-AS groups were significantly higher than that in CPDA-1 group at the 14th day (P<0.01). The concentrations of 2,3-DPG in the EP-AS and TAU-AS groups were significantly higher than that in the CPDA-1 group from the 7th day (P<0.01). CONCLUSION EP and TAU can significantly reduce the red blood cell hemolysis rate, inhibit the lipid peroxidation level of red blood cells, and improve the energy metabolism of red blood cells during storage. The mechanism of EP and TAU may be related to their antioxidation and membrane protection effect, so as to improve the red blood cell quality and extend the preservation time.
2,3-Diphosphoglycerate/metabolism* ; Adenine ; Adenosine Triphosphate/metabolism* ; Blood Preservation ; Citrates/pharmacology* ; Erythrocytes/metabolism* ; Glucose/pharmacology* ; Hemolysis ; Humans ; Pyruvates ; Taurine/pharmacology*

Organ transplantation is the most effective treatment for end stage organ failure,and voluntary donation after citizen's death is the only source of transplanted organ in China.Clinically,transplantation organ protection technology plays a critical role in improving the quality of transplantation organs and the prognosis of recipients.On the basis of domestic and worldwide basic research and clinical practice and according to the Oxford evidence classification and GRADE system,the experts organized by Organ Transplantation Doctor Branch of Chinese Medical Doctor Association,Organ Transplantation Group in Surgery Branch of Chinese Medical Association and China Liver Transplant Registry Scientific Committee had compiled and published the Chinese Expert Consensus on Organ Protection of Transplantation(2016 edition) for liver,kidney,pancreas,small intestine,heart,lung transplantation organs.With the support of China Liver Transplant Registry,National Center for Healthcare Quality Management in Liver Transplant,National Quality Control Center for Donated Organ Procurement,National Clinical Research Center for Orthopedics & Sports Medicine & Rehabilitation and National Trauma Medical Organ Protection Committee and combined with recent domestic and worldwide clinical practice and research progress for organ transplantation and organ protection,the Chinese Expert Consensus on Organ Protection of Transplantation(2022 edition)(hereinafter referred to as the consensus) has been formulated in 2022.This edition of the consensus focuses on updating the technical progress and evidence-based medicine of organ procurement,organ preservation,organ transport,and quality evaluation in clinical practice.Additionally,protection of composite tissue for transplantation,mainly including limb graft,has also been included.The organ protection strategy recommended in this consensus aims to promote scientific and standardize clinical organ transplantation work.
Asians ; Consensus ; Humans ; Organ Preservation ; Organ Transplantation ; Registries ; Tissue and Organ Procurement

BACKGROUND: Histidine-tryptophan-ketoglutarate (HTK) is a solution commonly used for organ transplantation. However, there is no certified fixed regimen for on-pump heart surgery in neonates. We aimed to retrospectively evaluate the outcomes related to different HTK dosages and to analyze the safety of high-dosage perfusion. METHODS: A total of 146 neonates who underwent on-pump heart surgery with single-shot HTK perfusion were divided into two groups according to HTK dosages: a standard-dose (SD) group (n = 63, 40 mL/kg < HTK ≤ 60 mL/kg) and a high-dose (HD) group (n = 83, HTK >60 mL/kg). Propensity score matching (PSM) was performed to control confounding bias. RESULTS: The SD group had a higher weight (3.7 ± 0.4 vs. 3.4 ± 0.4 kg, P < 0.0001), a lower proportion of complete transposition of the great artery (69.8% vs. 85.5%, P = 0.022), a lower cardiopulmonary bypass (CPB) time (123.5 [108.0, 136.0] vs. 132.5 [114.8, 152.5] min, P = 0.034), and a lower aortic x-clamp time (82.9 ± 27.1 vs. 95.5 ± 26.0 min, P = 0.005). After PSM, 44 patients were assigned to each group; baseline characteristics and CPB parameters between the two groups were comparable. There were no significant differences in peri-CPB blood product consumption after PSM (P > 0.05). The incidences of post-operative complications were not significantly different between the two groups. There were no significant differences in ventilation time, intensive care unit stay, and post-operative hospital stay (P > 0.05). Follow-up echocardiography outcomes at 1 month, 3 to 6 months, and 1 year showed that left ventricular ejection fraction and end-diastolic dimension were comparable between the two groups. CONCLUSIONS In neonatal on-pump cardiac surgery patients, single-shot HD (>60 mL/kg) HTK perfusion had a comparable heart protection effect and short-term post-operative prognosis as standard dosage perfusion of 40 to 60 mL/kg. Thus, this study provides supporting evidence of the safety of HD HTK perfusion.
Glucose/therapeutic use* ; Histidine ; Humans ; Infant, Newborn ; Mannitol ; Organ Preservation Solutions ; Potassium Chloride/therapeutic use* ; Prognosis ; Retrospective Studies ; Stroke Volume ; Tryptophan ; Ventricular Function, Left