Design principles of heterointerfacial redox chemistry for highly reversible lithium metal anode.

High electrochemical reversibility is required for the application of high-energy-density lithium (Li) metal batteries; however, inactive Li formation and SEI (solid electrolyte interface)-instability-induced electrolyte consumption cause low Coulombic efficiency (CE). The prior interfacial chemical designs in terms of alloying kinetics have been used to enhance the CE of Li metal anode; however, the role of its redox chemistry at heterointerfaces remains a mystery. Herein, the relationship between heterointerfacial redox chemistry and electrochemical transformation reversibility is investigated. It is demonstrated that the lower redox potential at heterointerface contributes to higher CE, and this enhancement in CE is primarily due to the regulation of redox chemistry to Li deposition behavior rather than the formation of SEI films. Low oxidation potential facilitates the formation of the surface with the highly electrochemical binding feature after Li stripping, and low reduction potential can maintain binding ability well during subsequent Li plating, both of which homogenize Li deposition and thus optimize CE. In particular, Mg hetero-metal with ultra-low redox potential enables Li metal anode with significantly improved CE (99.6%) and stable cycle life for 700 cycles at 3.0 mA cm-2. This work provides insight into the heterointerfacial design principle of next-generation negative electrodes for highly reversible metal batteries.

Dual-Functional Lithiophilic/Sulfiphilic Binary-Metal Selenide Quantum Dots Toward High-Performance Li-S Full Batteries.

The commercial viability of lithium-sulfur batteries is still challenged by the notorious lithium polysulfides (LiPSs) shuttle effect on the sulfur cathode and uncontrollable Li dendrites growth on the Li anode. Herein, a bi-service host with Co-Fe binary-metal selenide quantum dots embedded in three-dimensional inverse opal structured nitrogen-doped carbon skeleton (3DIO FCSe-QDs@NC) is elaborately designed for both sulfur cathode and Li metal anode. The highly dispersed FCSe-QDs with superb adsorptive-catalytic properties can effectively immobilize the soluble LiPSs and improve diffusion-conversion kinetics to mitigate the polysulfide-shutting behaviors. Simultaneously, the 3D-ordered porous networks integrated with abundant lithophilic sites can accomplish uniform Li deposition and homogeneous Li-ion flux for suppressing the growth of dendrites. Taking advantage of these merits, the assembled Li-S full batteries with 3DIO FCSe-QDs@NC host exhibit excellent rate performance and stable cycling ability (a low decay rate of 0.014% over 2,000 cycles at 2C). Remarkably, a promising areal capacity of 8.41 mAh cm-2 can be achieved at the sulfur loading up to 8.50 mg cm-2 with an ultra-low electrolyte/sulfur ratio of 4.1 µL mg-1. This work paves the bi-serve host design from systematic experimental and theoretical analysis, which provides a viable avenue to solve the challenges of both sulfur and Li electrodes for practical Li-S full batteries.

Recent Advances and Strategies toward Polysulfides Shuttle Inhibition for High-Performance Li-S Batteries.

Lithium-sulfur (Li-S) batteries are regarded as the most promising next-generation energy storage systems due to their high energy density and cost-effectiveness. However, their practical applications are seriously hindered by several inevitable drawbacks, especially the shuttle effects of soluble lithium polysulfides (LiPSs) which lead to rapid capacity decay and short cycling lifespan. This review specifically concentrates on the shuttle path of LiPSs and their interaction with the corresponding cell components along the moving way, systematically retrospect the recent advances and strategies toward polysulfides diffusion suppression. Overall, the strategies for the shuttle effect inhibition can be classified into four parts, including capturing the LiPSs in the sulfur cathode, reducing the dissolution in electrolytes, blocking the shuttle channels by functional separators, and preventing the chemical reaction between LiPSs and Li metal anode. Herein, the fundamental aspect of Li-S batteries is introduced first to give an in-deep understanding of the generation and shuttle effect of LiPSs. Then, the corresponding strategies toward LiPSs shuttle inhibition along the diffusion path are discussed step by step. Finally, general conclusions and perspectives for future research on shuttle issues and practical application of Li-S batteries are proposed.

Challenge and Strategies in Room Temperature Sodium-Sulfur Batteries: A Comparison with Lithium-Sulfur Batteries.

Metal-sulfur batteries exhibit great potential as next-generation rechargeable batteries due to the low sulfur cost and high theoretical energy density. Sodium-sulfur (Na-S) batteries present higher feasibility of long-term development than lithium-sulfur (Li-S) batteries in technoeconomic and geopolitical terms. Both lithium and sodium are alkali metal elements with body-centered cubic structures, leading to similar physical and chemical properties and exposing similar issues when employed as the anode in metal-sulfur batteries. Indeed, some inspiration for mechanism researches and strategies in Na-S systems comes from the more mature Li-S systems. However, the dissimilarities in microscopic characteristics determine that Na-S is not a direct Li-S analogue. Herein, the daunting challenges derived by the differences of fundamental characteristics in Na-S and Li-S systems are discussed. And the corresponding strategies in Na-S batteries are reviewed. Finally, general conclusions and perspectives toward the research direction are presented based on the dissimilarities between both systems. This review attempts to provide important insights to facilitate the assimilation of the available knowledge on Li-S systems for accelerating the development of Na-S batteries on the basis of their dissimilarities.

[A clinical study of haploid hematopoietic stem cells combined with third-party umbilical cord blood transplantation in the treatment of chronic granulomatous disease].

OBJECTIVE: To investigate the clinical efficacy of haploid hematopoietic stem cells (haplo-HSC) combined with third-party umbilical cord blood (tpCB) transplantation in the treatment of X-linked chronic granulomatous disease (X-CGD). METHODS: The clinical data of 26 boys with X-CGD were retrospectively analyzed who were admitted to the Sixth Medical Center of PLA General Hospital between April 2014 and March 2018. All the patients were treated with haplo-HSC combined with tpCB transplantation. The median age of the patients was 3.5 years. The donor was the father in 25 cases and an aunt in 1 case. Transplantation was 5/6 HLA-matched in 9 cases, 4/6 in 12 cases, and 3/6 in 5 cases. The patients received busulfan, cyclophosphamide, fludarabine, or anti-thymocyte globulin for myeloablative preconditioning. Cyclosporine A and mycophenolate mofetil were used for prevention of acute graft-versus-host disease (aGVHD). Then the patients were treated with haploid bone marrow hematopoietic stem cells combined with tpCB transplantation on day 1 and haploid peripheral hematopoietic stem cells on day 2. The counts of median donor total nucleated cells, CD34+ cells, and CD3+ cells were 14.6×108/kg, 5.86×106/kg, and 2.13×108/kg respectively. RESULTS: The median time to neutrophil and platelet engraftment was 12 and 23 days after transplantation respectively. Full donor hematopoietic chimerism was observed on day 30. Twenty-five cases were from haplo-HSC and 1 was from cord blood. No primary implant failure and implant dysfunction occurred, and secondary implant failure occurred in one case. The NADPH oxidase activity returned to normal one month after transplantation. The incidence of grade I-II aGVHD and grade III-IV aGVHD was 35% and 15% respectively. Chronic GVHD (cGVHD) of the skin occurred in one case, and no progression was observed after steroid administration. During the follow-up period of 6-51 months, 25 patients survived, of whom 24 were disease-free (23 patients without cGVHD and 1 with cGVHD of the skin) and NADPH oxidase activity returned to normal; one patient developed secondary implant failure but survived; one patient died of viral interstitial pneumonia 16 months after transplantation. The 5-year event-free survival rate and overall survival rate were 81%±12% and 89%±10% respectively. CONCLUSIONS: Haplo-HSC combined with tpCB transplantation is one of the effective methods for the treatment of X-CGD in children.

[Measures for Maintaining the Vitality of Peripheral Blood Hematopoietic Stem Cells in vitro].

OBJECTIVE: To explore the maintaining measures for the vitality of hematopoietic stem cells (HSC) in vitro, so as provide technical support for ultra long distance transport of HSC collected from unrelated donors. METHODS: Peripheral blood hematopoietic stem cells (PBHSC) were treated by different methods according to various groups, then stored at 4 ℃ in the refrigerator. The percentage of CD34+ cells, relative cell activity, relative cell proliferation rate, relative colony-forming rate, oxygen fraction and intracellular reactive oxygen species (ROS) were detected at 0, 24, 48 and 72 h after storage of PBHSC respectively. RESULTS: The percentage of CD34+ cells during 72 h storage did not altered. Along with the prolonging of storage time, the relative cell activity, relative cell proliferation rate and relative colony-forming rate gradually decreased in untreated PBHSC(control group), the related coefficients were -0.796, -0.883 and -0.815 respectively. Plasma dilution, antioxidants and oxygenation could improve the relative cell activity and relative cell proliferation rate, but oxygenation could decrease the relative colony-forming rate of PBHSC. The combination of 2 or 3 factors showed stronger protection effects on PBHSC. The intracellular level of ROS decreased gradually with the prolonging of storage time. Oxygenation of PBHSC could increase oxygen fraction, and also increase the intracellular level of ROS at the same time. The addition of antioxidants could reduce the level of ROS. CONCLUSION: The percentage of CD34+ cells can not serve as the indicator of PBHSC vitality. Plasma dilution, oxygenation and antioxidants can increase the survival and viability of PBHSC, but oxygenation can increase the intracellular ROS level and impair colony-forming ability of PBHSC. The combination of multiple factors can maintain the vitality of PBHSC better.

Construction of MOF-derived hollow Ni-Zn-Co-S nanosword arrays as binder-free electrodes for asymmetric supercapacitors with high energy density.

Mixed transition metal sulfides with hollow structures hold great promise for energy-related applications. However, most of them are in the powder form, which should be mixed with unwanted polymer binders and conductive agents. In this study, a facile two-step strategy has been developed to grow mesoporous and hollow Ni-Zn-Co-S nanosword arrays (NSAs) on a nickel foam (NF) substrate with robust adhesion, which involves the hydrothermal growth of bimetallic Zn-Co-ZIF NSAs on NF and subsequent transformation into hollow Ni-Zn-Co-S NSAs through the sulfurization process. Benefiting from the unique structural and compositional advantages as well as directly grown conductive substrate, the Ni-Zn-Co-S-0.33 NSAs/NF electrode exhibits the best electrochemical performance when investigated as a binder-free electrode for supercapacitors. Impressively, the Ni-Zn-Co-S-0.33 NSAs/NF electrode delivers a high areal capacity of 1.11 mA h cm-2 at the current density of 10 mA cm-2, and the corresponding specific capacity is as high as 358.1 mA h g-1. Moreover, an asymmetric supercapacitor (ASC) device based on the Ni-Zn-Co-S-0.33 NSAs/NF as the positive electrode and Bi2O3/NF as the negative electrode has been successfully fabricated, and can deliver a high energy density of 91.7 W h kg-1 at a power density of 458 W kg-1 and maintain the energy density of 66.9 W h kg-1 at a high power density of 6696 W kg-1. The electrochemical results suggest that the hollow Ni-Zn-Co-S NSAs would possess great potential for applications in high-performance supercapacitors.

[Biological characteristics of wharton's jelly derived mesenchymal stem cells after cryopreservation].

Aim of this study was to explore the effects of cryopreservation on biological characteristics of wharton's jelly derived mesenchymal stem cells (WJ-MSC), and to provide experimental evidence for clinical applications and the establishment of WJ-MSC bank. Primary WJ-MSC were produced by umbilical cord tissue culture in vitro. Fifth passage of WJ-MSC acquired by continuous cell culture were mixed with cryoprotectants, frozen in -80°C refrigerator and stored in liquid nitrogen. After the cryopreserved WJ-MSC were thawed, the first passage of WJ-MSC was obtained through cell culture and was taken as the 1st preserved passage (PP1). Thus, PP2-PP15 WJ-MSC were obtained by continuous cell subculture. The 1st control passage (CP1) to 15th passage (CP15) represented the 6th passage to 21st passage WJ-MSC acquired by subculturing in non-cryopreserved group. The biological characteristics of WJ-MSC from cryopreserved and control group, including the recovery rate of nucleated cells, trypan blue exclusion, CCK-8 activity, cell apoptosis, cell adherence, proliferation index, cell surface antigen, cell cycle and the capacities of induced differentiation into adipocyte, osteoblast and neuron, were detected and compared. The results indicated that the recovery rate of nucleated cells of cryopreserved WJ-MSC was 98.2%, trypan blue exclusion rate was 94.3%, CCK-8 activity was 91.4%, apoptotic rate was 3.9%, and the adherence rate was 92.6%. There was a statistically significant difference in proliferation index between PP1 and CP1 (P < 0.05), but there were no statistically significant differences between PP2-PP15 and their corresponding controls. The subculture cells highly expressed CD29, CD44, CD71, CD73, CD90, CD105, CD166 and HLA-ABC, and lowly expressed CD34, CD45 and HLA-DR. The expressions of above-mentioned surface antigens were not different statistically between two groups. The proliferation latency and logarithm proliferation of the subculture cells between two groups were also not different. After induced differentiation into adipocyte, osteoblast and neuron, the staining with oil red O, alkaline phosphatase and neuron-specific enolase was performed respectively, and the positive degrees were not clearly different macroscopically between two groups. Relatively high levels of triglyceride, alkaline phosphatase, and neuron-specific enolase in relevant cells could be detected, but had no significant differences between two groups. It is concluded that some WJ-MSC (< 10%) are damaged after cryopreservation, and the biological characteristics of WJ-MSC in cryopreservation group keep constant, as compared with that in non-cryopreservation group.

[Morphologic diagnosis and onset characteristics of acute leukemia: a retrospective analysis of 233 cases in 10 years].

The objective of this study was to evaluate the value of morphologic diagnosis for acute leukemia (AL), to explore the relation of morphologic diagnosis with immunology, cytogenetics and molecular biology diagnosis of AL and to analyze the onset characteristics of AL in 10 years. The samples of bone marrow and peripheral blood from 233 newly diagnosed cases of AL were collected during 2001-2011 years; the morphologic examination and immunologic, cytogenetic and molecular biologic examination (ICM) were carried out, the consistency of morphologic diagnosis with ICM diagnosis was compared, the onset characteristics of AL was analyzed. The results showed that: (1) the consistent rate of immunology, cytogenetics, molecular biology diagnosis with morphologic diagnosis was 84.3%. The order of consistent rat was AUL, M0 < M1 < HAL < M4 < M2 < M3 < M5 < ALL < M6, M7, AP; (2) Misdiagnosis always occurred among AUL, M0, M1, ALL and HAL or among M2a, M3v, M4 and M5. (3) In 233 cases, the highest ratio of blast was observed in M1 (92.5%), while the lowest ratio of blast was observed in M2 (49.5%). (4) AL occurred more frequently in males than that in female (147:86). (5) AL occurred in patients aged from 1 to 88 years. The median age was 41.5 for AUL, 40.8 for M0, 43.4 for M1, 46.3 for M2, 33.8 for M3, 42.6 for M4, 48.8 for M5, 77.3 for M6, 2.5 for M7, 65.0 for AP, 29.1 for ALL and 40.3 for HAL. (6) The number of patients in the later five years (139 cases) was significantly greater than that in the first five years (94 cases), especially the patients with M1, M2, M3, M4, and M5. It is concluded that morphologic diagnosis has important clinical value in the MICM diagnosis of AL. Attaching importance to the confusing cell morphology and onset characteristics of AL can improve the diagnostic accuracy.

Effect of Yifei Huoxue Granule on the proliferation of rat pulmonary artery smooth muscle cells upon exposure to chronic hypoxic conditions in vitro.

OBJECTIVE: To investigate the inhibitory effect of Yifei Huoxue Granule (, YFHXG) on the hypoxia-induced proliferation of rat pulmonary artery smooth muscle cells (PASMCs) and its mechanism of decreasing pulmonary arterial pressure. METHODS: Twenty male Sprague-Dawley (SD) rats were randomly divided into four groups: saline, and 0.66, 3.30 and 16.50 g/kg of YFHXG groups, the saline and different concentrations of YFHXG were given twice daily for 7 days, respectively. Serum-pharmacology method was used in the preparation of YFHXG serum. Tissue block anchorage was employed in the primary culture of rat PASMCs. The PASMCs were randomly divided into normoxia group, hypoxia group, and hypoxia+YFHXG group (0.66, 3.30 and 16.50 g/kg doses of YFHXG-treated serum groups, exposed to hypoxic condition). PASMCs in normoxia and hypoxia group were cultured with saline serum, hypoxia+YFHXG groups were cultured with different concentrations of YFHXG serum. Cell viability was assessed with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle was analyzed using flow cytometry. In addition, hypoxia inducible factor-1-alpha (HIF-1α) protein expression was evaluated by immunocytochemistry analysis, the concentration of intracellular reactive oxygen species (ROS) and Ca(2+) were determined by laser scanning confocal microscopy (LSCM). RESULTS: MTT assay and flow cytometry showed that hypoxia could directly activate the proliferation of PASMCs, while YFHXG dose-dependently inhibited hypoxia-induced proliferation of rat PASMCs. Immunocytochemistry showed that hypoxia enhanced HIF-1α protein expression, and LSCM showed that hypoxia significantly increased intracellular ROS and Ca(2+), while YFHXG decreased the expression of HIF- 1α and attenuated the hypoxia-induced increase in intracellular concentration of ROS and Ca(2+). CONCLUSIONS: YFHXG could inhibit hypoxia-induced proliferation of rat PASMCs, which may decrease pulmonary arterial pressure and vascular remodeling. The anti-hypoxia effect of YFHXG may be explained by its regulation of HIF-1α expression and of the levels of intracellular ROS and Ca(2+).

[Influence of mesenchymal stem cells on proliferation of HL-60].

The objective of this study was to explore the effect of mesenchymal stem cells (MSC) on HL-60 proliferation and its molecular mechanism. HL-60 cells co-cultivated with MSC were used as experiment group, and the cells cultivated solely were taken as control group. HL-60 cells in the two groups were counted at different time. The time-quantity curve was drawn. The cell cycle and apoptosis ratio of HL-60 cells were compared between the two groups and expressions of Survivin and Bcl-2 protein were detected by flow cytometry. The results showed that HL-60 cells cultivated with MSC were obviously inhibited, especially on day 5 and 7 (P < 0.01). HL-60 cells were distributed on the phase of G(0)/G(1) [control group (47.0 ± 9.0)% vs experiment group (70.0 ± 16.0)%, P = 0.003], and apoptotic peak appeared. Both of Survivin and Bcl-2 protein expressions in HL-60 cells decreased [Bcl-2 protein in control group (63.0 ± 9.1)% vs experiment group (50.0 ± 14.1)%, P = 0.045; Survivin in control group (94.0 ± 9.3)% vs experiment group (77.0 ± 11.8)%, P = 0.006]. It is concluded that the MSC can inhibit HL-60 cell proliferation, and promote HL-60 cell apoptosis.

Effectiveness of human mesenchymal stem cells derived from bone marrow cryopreserved for 23-25 years.

OBJECTIVE: To evaluate long-term cryopreserved human bone marrow cells (BMCs) as a source of functional mesenchymal stem cells (MSCs). METHODS: Samples of human BMCs that were cryopreserved for 23-25 years (n=20) were thawed to obtain an initial culture and a primary culture (P(0)) that was propagated through five passages (P(1)-P(5)) to obtain MSCs. Freshly collected human bone marrow samples (n=20) were used as controls for comparison of efficiency of recovery and growth characteristics of MSCs. P(3) cultures were tested for their capacity to differentiate into osteoblasts, adipocytes, and neuronal cells. Appropriate staining, immunohistochemical and biochemical methods were employed to ascertain cell type identities at different stages of culturing. RESULTS: In the initial culture, the cell adherence rate of the cryopreserved cells was significantly lower than that of controls (19.7% vs. 38.2%, p<0.05) while the relative rate of recovery of MSCs was only 48.5±8.6% in P(0). At the end of P(3), fibroblast-like cells accounted for about 95% of cells in both cryopreserved and control groups (p>0.05). These cells were positive for essential MSC surface molecules (CD90, CD105, CD166, CD44, CD29, CD71, CD73) and negative for haematopoietic and endothelial cell markers (CD45, CD34, HLA-DR). The cell growth and cell cycle patterns were similar for both groups. MSCs at P(3) from both groups had similar capacities to differentiate in vitro into osteoblasts, adipocytes, and neuronal cells. CONCLUSION: Using the methods described here, long-term (23-25 years) cryopreserved human BMCs can be successfully cultivated to obtain MSCs that have good differentiation capabilities.

[Effect of yifei huoxue granule on the proliferation and the TGF-beta activity of rat pulmonary artery smooth muscle cells induced by platelet-derived growth factor BB].

OBJECTIVE: To explore the effects of Yifei Huoxue Granule (YFHXG) on the proliferation and the transforming growth factor-beta (TGF-beta) activity of rat pulmonary artery smooth muscle cells (PASMCs) induced by platelet-derived growth factor BB (PDGF-BB). METHODS: Using tissue block adhering wall method, the primary rat PASMCs were cultured. PASMCs at the log phase growth were randomly divided into the control group, the PDGF-BB group, the PDGF-BB + high YFHXG group (at the final concentration of 7.5 mg/mL), the PDGF-BB + middle YFHXG group (at the final concentration of 1.5 mg/mL), and the PDGF-BB + low YFHXG group (at the final concentration of 0.3 mg/mL), respectively. MTT assay were employed to determine the cell proliferation rate of each group. Flow cytometric analyses were used to detect the cell cycle constituent ratio and the proliferation index (PI). In addition, TGF-beta protein's expression was determined by immunocytochemical assay (SP method). RESULTS: Compared with the control group, the proliferation of PASMCs in the PDGF-BB group was obviously active (P<0.01). But when compared with the PDGF-BB group, along with the increased concentration of YFHXG, the growth of PASMCs was obviously inhibited, the cell ratio of G0/G1, phase obviously increased, the cell ratio of S + G2/M phase significantly decreased, and PI significantly decreased. Besides, the expression of TGF-beta protein decreased in a dose-dependent manner (P<0.05, P<0.01). CONCLUSIONS: PDGF-BB could directly stimulate the proliferation of PASMCs. YFHXG had a significant inhibition on the proliferation of rat PASMCs induced by PDGF-BB and could regulate the expression of TGF-beta.

[The effects of thrombopoietin on the fibrogenesis of bone marrow stromal cells in absence of megakaryocytes].

OBJECTIVE: In order to investigate whether or not thrombopoietin (TPO) could promote the fibrogenesis of bone marrow stromal cells in absence of megakaryocytes (MKs). METHODS: Improved dexter culture system with various TPO concentrations was used for ex vivo culture of bone marrow stromal cells. Relative proliferation index, the expressions of fibronectin, laminin and type IV collagen, and the systhesis of type III procollagen were detected at different time points during culture process. RESULTS: TPO stimulated the proliferation of bone marrow stromal cells. Relative proliferation index of the stromal cells increased with the TPO concentration increasing, and was not related to the exposure time. The expressions of fibronectin, laminin, and type IV collagen appeared stronger in the TPO groups than those in the control group. But the expressions of these molecules were not dependent upon the culture time. TPO could accelerate the synthesis of type III procollagen in bone marrow stromal cells, and this acceleration was unrelated to the TPO concentration. CONCLUSION: These findings suggested that TPO could stimulate the stromal cells with a consequence of increased syntheses and secretions of the extracellular matrix and collagen in absence of MKs. In other words, TPO could promote the fibrogenesis of bone marrow stromal cells without the existence of MKs.

[In vitro activity of human bone marrow cells after cryopreservation in liquid nitrogen for 21 - 25 years].

The aim of this study was to investigate the best method to preserve human bone marrow cells and the effectiveness of long term cryopreservation at -80 degrees C. The human bone marrow cells in 20 samples were firstly frozen by a programmed freezer or -80 degrees C refrigerator, and then were preserved in liquid nitrogen with DMSO-AuP (10% dimethylsulfonamide, 10% autologous plasma) or DMSO-HES-HuA (5% dimethylsulfonamide, 6% hydroxyethyl starch, 4% human serum albumin) as cryoprotectant for 21 to 25 years. They were thawed in 38 degrees C. The cell sample frozen in -80 degrees C refrigerator was frozen at a low frozen speed of 1 degrees C/min which was the same as the programmed freezer before -30 degrees C. Before detection the bone marrow cells were taken from liquid nitrogen and were thawed in 38 degrees C, then the suspension of bone marrow cells was prepared for detection. The cell morphology and recovery rate of erythrocytes, nucleocytes and platelets; the recovery rate of hematopoietic stem progenitors cells, as well as mesenchymal stem cells were determined. The results showed that the protective effectiveness of DMSO-HES-HuA was better than DMSO-AuP. The mature erythrocytes were destroyed lightly [(3.5 +/- 1.5)% versus (12.6 +/- 4.8)%], the hemolysis rate was lower [(3.3 +/- 1.6)% versus (23.1 +/- 5.1)%]. Osmotic fragility of erythrocytes in the former was not changed, but was dropped in the latter. The recovery rates of red cell, platelet, granulocyte-macrophage colony forming units and long term culture-initiating cells were higher in the former than that in the latter [(96.1 +/- 1.8)%, (70.0 +/- 9.5)%, (49.2 +/- 10.9)%, (54.2 +/- 13.8)% versus (76.3 +/- 5.6)%, (52.7 +/- 8.1)%, (43.5 +/- 12.3)%, (47.2 +/- 13.6)% respectively]. With each kind of cryoprotectant or frozen method, the frozen MSC could keep the original growth properties. With the same cryoprotectant and different frozen method, the cryopreservative effectiveness was not different. The influence of the cryoprotectant prescriptions and the frozen methods on the cryopreservative effectiveness was little. It is concluded that the human bone marrow cells with DMSO-AuP or DMSO-HES-HuA as cryoprotectant, frozen by a programmed freezer or -80 degrees C refrigerator, could be then preserved in liquid nitrogen for long time. When the preserving time was as long as 21 to 25 years, the morphology, the recovery rate and the activity of various kinds of cells were still good. The method of freezing by -80 degrees C refrigerator with 5% DMSO-6% HES-4% HuA and preserving in liquid nitrogen would be convenient, cheap and easily-manipulated for preservation of the human bone marrow cells.

[Influences of bone marrow mesenchymal stem cells in patients with acute myeloid leukemia and non-leukemia on HL-60 cells -- a comparison study].

This study was aimed to compare the influences of bone marrow mesenchymal stem cells (BMMSCs) from patients with acute myeloid leukemia (AML), AML patients with complete remission (CR) and non-leukemia patients on HL-60 cells. The HL-60 cells were divided into three groups: group of co-cultivation with BMMSCs of AML patients, group of co-cultivation with BMMSCs of AML patients with CR and group of co-cultivation with BMMSCs of non-leukemia patients. The count of HL-60 cells, the CD11b and survivin expression of HL-60 cells, the cell cycle distribution of the HL-60 cells in 3 groups were compared by flow cytometry, the morphology and differentiation rate of HL-60 cells in 3 groups were observed and compared by microscopy. The results showed that there were no differences in HL-60 cell count at five and seven days, in HL-60 distribution at the G(0)/G(1) phase, in survivin and CD 11b expressions in 3 groups. All cells of 3 groups began to mature, and the differentiation rates in 3 groups were 18.0 +/- 3, 17.0 +/- 1.3 and 19.0 +/- 2.0 respectively, therefore there were no significant differences between the 3 groups (p = 0.23). It is concluded that there is no influence of BMMSCs in 3 groups on the proliferation and differentiation of HL-60 cells.

[Effects of recombinant human thrombopoietin on stromal cells in culture in vitro].

This study was aimed to investigate whether the thrombopoietin (rhTPO) may facilitate myelofibrosis or not. The modified Dexter culture system with various concentrations of rhTPO was used to culture the stromal cells in vitro; the proliferative activity of cells was detected by MTT method; the morphologic changes were observed by light and scanning electron microscopy; the staining changes of ALP, PAS, AS-D NCE and IV type collagen were observed by cytochemistry method; the changes of fibronectin, laminin and IV type collagen were assayed by immunohistochemistry method; the cell surface antigens were assayed by flow cytometry. The results indicated that rhTPO could promote the proliferation of stromal cells which was related to the concentrations of rhTPO. Proliferative activity of stromal cells increased with increasing of rhTPO concentration, and was not related to the exposure time. On day 3 stromal cells adhered to the wall, and became oval. On day 7 stromal cells turned to fusiform and scattered dispersively. On day 12 to 14 these cells ranged cyclically and became long fusiform. Cells covered 70%-80% area of bottle bottom at that time. By day 16 to 18 these cells covered more than 90% area of bottom and ranged cyclically. They displayed the same shape as fibroblasts. By light microscopy with Wrights-Giemsa staining, fibroblasts predominated morphologically, few macrophages, endothelial cells and adipose cells were found. There were no significant differences between experimental group and control group. On day 14 to 42 the adherent cells were positive with PAS staining, poorly positive with ALP and naphthol AS-D chloroacetate esterase (AS-D NCE) staining, and the difference in cytochemistry was not significant between two groups. When these cells were dyed with Masson's trichrome and Gomori's staining, neither collagen fibers nor reticular fibers were positive, but fibronectin, laminin, and collagen type IV appeared positive stronger in experimental group than those in control. The expressions of these molecules were not dependent on culture time. By scanning electron microscopy microvilli and fibers on cell surface appeared more and more, monolayer cells evolved into multilayer cells, and newly-formed fibroblasts appeared gradually as culture time prolonged. These alterations were not different among various groups. The expressions of CD34, CD45, CD105, CD106, and CD166 were not affected obviously by rhTPO. It is concluded that rhTPO had no effects on histochemical properties of stromal cells. Fiber staining and scanning electron microscopic examinations revealed that rhTPO can not facilitate fiber formation of stromal cells. But rhTPO may be able to augment the expressions of fibronectin, laminin and collagen type IV of stromal cells. Therefore it is still necessary to follow up the patients for a long time, who have received rhTPO therapy clinically.

[Change in coagulation after open abdominal wound subjected to seawater immersion].

OBJECTIVE: To explore the effects of hyperosmotic fluid and low temperature on hemorrhage and coagulation system after immersion of dogs with open abdominal wounds in seawater. METHODS: Twenty healthy dogs were subjected to open abdominal injury, then dogs were randomized equally into two groups: the control group (n=10) (without seawater immersion) and seawater immersion group (n=10). The variables of prothrombin time (PT), partial thromboplastin time (APTT), D-dimer and factor II, granule membrane protein-140 (GMP-140), endothelin-1 (ET-1) were determined. RESULTS: PT and APTT were significantly prolonged. D-dimer, GMP-140, and ET-1 were increased, while factor II was decreased after the dog with open abdominal wound was immersed in seawater (all P<0.05). Compared with the variables of control group, PT, APTT, D-dimer and factor II, ET-1 in seawater immersion group had markedly changed (all P<0.05) except GMP-140 at different time points (all P>0.05). CONCLUSION: Obvious vascular endothelial cell dysfunction, platelet activation, inhibition of coagulation factor activity, coagulopathy, and disorders in thrombosis and fibrinolysis system activation occur after dogs with open abdominal wounds are immersed in seawater.

[Unrelated umbilical cord blood transplantation as a treatment for children with malignant leukemia].

OBJECTIVE: Unrelated umbilical cord blood has the clear benefits of rapid availability and a reduced stringency of requirement for HLA match. The aim of this study was to investigate the efficacy of unrelated umbilical cord blood transplantation (UCBT) in the treatment of malignant leukemia in children. METHODS: Six children with malignant leukemia, including three cases of acute lymphocyte leukemia [two high-risk patients and one standard-risk patient in complete remission (CR)], two juvenile myelomonocytic leukemia (one in CR and one in the accelerating stage), and one acute myeloblastic leukaemia (in CR), received a UCBT. The umbilical cord blood grafts were HLA-matched (n=1) or HLA-mismatched at 1 (n=1) or 2 (n=1) or 3 (n=3) loci. Busulfan/cyclophosphamide/antithymocyte globulin (ATG) or total body irradiation (TBI)/cyclophosphamide/ATG was involved in the myeloablative pretreatment regimen. The median infused donor nucleated cell was 8.51 x 10(7)/kg of recipient weight, and the CD34+ cell was 1.81 x 10(5)/kg of recipient weight. Cyclosporin, corticoid, mycophenolate mofetil and daclizumab were used for prophylaxis of acute graft versus host disease (GVHD). RESULTS: The time to reach an absolute neutrophil count of 0.5 x 10(9)/L ranged from 11 to 35 days (median: 13 days) and the time to reach a platelet count of 20 x 10(9)/L ranged from 27 to 68 days (median: 30 days) after transplantation, and the donors' hematopoietic stem cells were shown in these patients. Four patients developed grade I to III acute GVHD but responded to steroids and daclizumab. Chronic GVHD was not found during a 3-16-month follow-up. Four patients survived and did not relapse during the follow-up. CONCLUSIONS: Unrelated umbilical cord blood is an alternative source of hematopoietic stem cells for patients with leukemia. UCBT can tolerate 1-2 HLA mismatches. The incidence of acute GVHD is high in UCBT recipients.