一种模拟三维红细胞变形的前向跟踪式格子B0ltzmann方法

将前向跟踪法与晶格波尔兹曼法相结合,研究三维双凹碟形胶囊式红细胞的变形.将红细胞模拟为内含牛顿流体的双凹碟形弹性薄膜胶囊,将薄膜内外的液体看做是具有不同物理特性的流体;使用晶格波尔兹曼方法的多块策略,改善细胞模型附近的网格,增加三维计算的准确度和效率.使用的细网格仅覆盖每个计算轴的40%,较同时选用离散为连接4 098个点的8 192个三角元的细胞薄膜模型,这不仅可以提高网格分辨率,而且还能节省计算时间.从理论上证明,在雷诺数不大于0.25的剪切流中,惯性作用对细胞变性的影响很小,同时得到无因次参数为0.05、细胞内外黏度比为0.2时三维健康红细胞的360.稳定坦克履行为.不仅成功模拟了惯性作用下典型的三维红细胞坦克履行为,而且使用的细网格仅占整个计算区域的6.4%,在保证计算准确度的同时,提高了计算效率,为模拟三维红细胞变形提供了一种更加可行的途径.     

血红蛋白氧载体的研究目标及新进展

文题释义：血红蛋白氧载体：以血红蛋白为原料,通过交联、聚合、偶联等化学修饰或者将其封装在人工合成的膜中,得到一种具有运载氧气能力的红细胞替代物。 红细胞替代物：通过模拟天然红细胞生物学功能的氧载体,主要包括基于全氟碳的乳剂、含铁(Fe²⁺)卟啉和基于血红蛋白的氧载体。与红细胞相比,红细胞替代物具有降低感染风险、延长储存时间、在使用时无需配型等优点。 背景：血红蛋白氧载体作为红细胞替代物之一,已研究40余年,至今共有3代不同的血红蛋白氧载体。第1代和第2代主要是对血红蛋白进行化学修饰,而第3代主要是将血红蛋白封装在合成膜中。 目的：综述国内外血红蛋白氧载体研究的新进展。 方法：以“hemoglobin-based oxygen carriers,red blood cell substitutes,artificial oxygen carriers ,artificial blood”“血红蛋白氧载体,红细胞替代物,人工氧载体,人工血液”为检索词,检索2000至2019年PubMed、CNKI中国期刊全文数据库、万方数据库中收录的血红蛋白氧载体制备方法的相关文献,进行总结分析。 结果与结论：①胎儿、无脊椎动物、爬行动物的血红蛋白以及β-亚基突变的血红蛋白在制备血红蛋白氧载体上有一定优点;②关于血红蛋白的修饰和封装策略有了新的进展;③联合使用其他药物能够降低血红蛋白氧载体的血管毒性;④血红蛋白氧载体在应用上有了新方向,但是新型血红蛋白氧载体作为红细胞替代物领域的研究,在未来还需要更多的动物实验和临床试验。 ORCID: 0000-0003-4004-115X(杨康) 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

血氧饱和度降低可促进红细胞氧化损伤

研究氧化应激条件下,血氧饱和度(SO2)对红细胞氧化损伤的影响。体外将红细胞孵育至SO2分别为0.3、0.5、0.7、0.9及0.98等状态,加入终浓度为0.15mmol/L叔丁基过氧化氢(BHP)使其发生氧化应激反应。测量胞内还原性谷胱甘肽(GSH)含量反映细胞抗氧化力,以胞内高铁血红蛋白(MetHb)、膜质过氧化(TBARS)及膜上沉淀的变性珠蛋白链水平体现细胞氧化损伤程度。结果显示,BHP存在的条件下,GSH含量随SO2上升而增加;MetHb、TBARS及膜上珠蛋白链水平则随SO2的上升而下降。上述结果表明,氧化应激条件下,红细胞抗氧化力和氧化损伤与SO2密切相关,SO2的降低可促进红细胞氧化损伤。     

肾阳虚证患者红细胞LPO、SOD和ATP酶活性的变化

目的 :探讨肾阳虚证患者红细胞LPO、SOD和ATP酶活性的特点及其意义。方法 :观察 19例肾阳虚证患者和 2 1例正常人红细胞LPO、SOD和红细胞膜Na+ K+ ATP酶、Mg2 + ATP酶、Ca2 + ATP酶、Ca2 + Mg2 + ATP酶活性的变化。结果 :与对照组比较 ,肾阳虚证患者红细胞LPO含量升高 (P <0 .0 1) ,红细胞SOD活性降低 (P <0 .0 1) ;红细胞膜Na+ K+ ATP酶活性显著升高 (P <0 .0 1) ,而Mg2 + ATP酶活性变化无显著性差异 ,Ca2 + ATP酶活性升高 (P <0 .0 1) ,Ca2 + Mg2 + ATP酶活性也显著升高 (P <0 .0 1)。结论 :肾阳虚证患者红细胞内脂质过氧化反应增强 ,而抗氧化能力降低 ,红细胞膜Na+ K+ ATP酶、Ca2 + ATP酶和Ca2 + Mg2 + ATP酶活性升高 ;本研究为理解肾阳虚证的病理生理基础提供了初步实验依据     

重建红细胞形态及力学特性研究

红细胞的生物力学性质与其功能有着密不可分的联系,本文对重建红细胞形态及力学特性的研究结果显示重建红细胞的力学特性与天然红细胞相似;重建红细胞具备良好的可变形性,具有天然红细胞双凹蝶盘形态.研究说明重建红细胞的生理功能与天然红细胞相似.     

间断性低氧暴露对红细胞参数及血清HIF-1α、EPO的影响

目的:探讨间断性低氧暴露及复氧休息对红细胞参数及血清低氧诱导因子-1α(HIF-1α)、促红细胞生成素(EPO)的影响.方法:制备间断性低氧动物模型,检测全血RBC、Hb、HCT红细胞参数,采用ELISA法检测血清HIF-1α、EPO水平,结合现场调查,检测间断性高原作业人员红细胞参数及EPO水平.结果:IH7、14、21、28 d组大鼠RBC、Hb、HCT水平明显高于常氧对照组(P<0.05),复氧后各参数水平下降.IH3、7、14 d组HIF-1α高于常氧对照组(P<0.05),EPO在IH3、7 d组高于对照组(P<0.05),复氧后HIF-1α、EPO水平下降.8个月组高原作业人员RBC水平高于平原对照组(P<0.05),Hb在2年组高于平原对照组(P<0.05).HCT与RBC大致呈同一规律,且2年组HCT仍明显高于平原对照组(P<0.05).与平原对照组比较,各组EPO的差异不显著.结论:间断性低氧暴露可以增加血清HIF-1α、EPO的含量,提高红细胞数量和血红蛋白的浓度,并随低氧周期的延长存在一定变化规律;复氧休息有利于低氧后机体的调整,使升高的红细胞参数及HIF-1、EPO水平下降.     

红细胞膜输氧作用与红细胞变形问题的初探(摘要)

本文讨论了红细胞膜输O_2功能与红细胞变形的关系,提出了当P_1P~0时,红细胞膜有吐出O_2的现象.其O_2的总流率为     

模拟高原不同时间缺氧暴露对大鼠红细胞结构与功能的影响

目的:初步探讨模拟高原不同时间缺氧暴露对大鼠红细胞结构与功能的影响及机制。方法:40只雄性SD大鼠随机分成5组(每组8只):常氧组、缺氧1周组、缺氧2周组、缺氧3周组和缺氧4周组。各缺氧组大鼠置于模拟海拔5 800 m的低压舱内,连续暴露相应时间后,采集全血,测定血常规、红细胞变形指数和红细胞渗透脆性,绘制血红蛋白氧解离曲线,分析计算红细胞凋亡率,观察骨髓切片病理学变化。结果:与常氧组相比,各缺氧组红细胞计数、血红蛋白含量、红细胞平均体积、红细胞平均血红蛋白含量和磷脂酰丝氨酸外翻率均显著增加(P0.01),血红蛋白氧饱和度为50%时的氧分压显著增大(P0.05),骨髓红系增生增加,红细胞变形指数及渗透脆性显著降低(P0.01),血红蛋白氧离曲线右移。结论:在模拟高原缺氧初期,外周血中红细胞的结构与功能发生代偿性改变以利于高原习服;但是,随着缺氧时间的延长,血管内滞留过多的异常红细胞容易导致血栓形成及微循环障碍,并加重机体的组织细胞缺氧。     

CD47-SIRPα在人类红细胞老化与吞噬过程中的作用

探讨CD47-SIRPα在人类红细胞衰老与吞噬过程中的作用。采用Western blot检测体外4℃和37℃保存红细胞(RBC)及老化过程中红细胞膜上CD47的表达量;用单核细胞单层分析试验(monocyte monolayer assay,MMA)观察人THP-1单核细胞系对不同年龄段红细胞和CD47抗体F(ab’)2端封闭红细胞的吞噬情况及Western blot检测THP-1细胞上SIRPα磷酸化情况。结果发现,无论是在体内老化还是体外老化过程中,红细胞膜上CD47的表达量均出现显著下降趋势,随着保存时间的延长,CD47的表达量最大可下降82.64%(4℃保存情况下);THP-1细胞对不同年龄段红细胞的吞噬情况存在差异性,更易吞噬年老红细胞,吞噬率为35.32%,对年轻红细胞的吞噬率为13.72%(n=7,P<0.02);对新鲜红细胞的吞噬率为2.22%,对CD47抗体F(ab’)2端封闭红细胞的吞噬率为31.51%(n=7,P<0.02);吞噬不同年龄段红细胞后,THP-1细胞上磷酸化SIRPα量不同,与吞噬年轻红细胞相比,吞噬年老红细胞后,磷酸化SIRPα的量下降了57.12%。表明人类红细胞的老化与吞噬过程和CD47-SIRPα相互作用存在密切关系。     

用原子力显微镜观察术中失血回收对红细胞形态的影响

目的: 采用原子力显微镜(AFM)观察术中失血回收对红细胞外貌及膜超微结构的影响。方法: 择期脊柱手术患者,术中应用自体血液回收机,切皮前采集外周静脉血2 mL(T1),洗涤前血液2 mL(T2),洗涤后血液2 mL(T3),回输洗涤血1 h后外周静脉血2 mL(T4),肝素抗凝。采用荧光正置显微镜观察红细胞畸形率及AFM观察红细胞膜表面超微结构。结果: T1时刻红细胞畸形率 低于T2 、T3 和T4 (P<0.05),而后三者红细胞畸形率并无显著差异。回收血和静脉血红细胞AFM形貌、红细胞膜表面蛋白颗粒分布均存在显著差异。T2红细胞膜表面平均粗糙度、均方根粗糙度高于其它时点收集的红细胞(P<0.05)。结论: 术中自体血液回收可增加红细胞畸形率,改变红细胞AFM形貌及膜表面超微结构 。     

脾动脉流量和脾静脉压力的变化对脾脏储存血液和红细胞的影响

根据脾循环的特点,提出了脾循环的流动模型,应用该模型,从理论上探讨了增加脾动脉流量和升高脾静脉压力对脾脏储存血液和红细胞的影响。分析表明：当脾动脉流量增加或脾静脉压力升高时,脾的体积增大、脾内血球比积增加、储存的红细胞增多。为了验证理论分析的正确性,对离体的狗脾脏进行了增加脾动脉流量和升高脾静脉压力的实验研究,实验结果同理论分析相一致。     

Lacking deoxygenation-linked interaction between cytoplasmic domain of band 3 and HbF from fetal red blood cells

AIM: Several of the red blood cell's metabolic and membrane functions display dependence on haemoglobin oxygenation. In adult human red cells, the increased glycolytic rate at low O2 tension results from binding of deoxygenated HbA at negatively charged, N-terminal, cytoplasmic domain of the membrane protein band 3, which liberates glycolytic enzymes from this site. This study aims to investigate the role of fetal HbF (that has lower anion-binding capacity than HbA) in fetal red cells (that are subjected to low O2 tensions), and to elucidate possible linkage (e.g. via the major red cell membrane organising centre, band 3) between the individual oxygenation-linked reactions encountered in red cells. METHODS: The interaction between band 3 and Hb is analysed in terms of the effects, measured under different conditions, of a 10-mer peptide that corresponds to the N-terminus of human band 3 protein, on the oxygenation reaction of HbF and HbA, isolated from umbilical chord red cells. RESULTS: Contrasting with the unequivocal interaction of the peptide with HbA that with fetal HbF is weak, and annihilated in the presence of autochthonous red cell O2 affinity modulators (chloride and organic phosphates). CONCLUSION: The data indicate that HbF does not function as a transducer mediating O2 dependence of glycolysis in fetal red cells, in accordance with the different O2 and metabolic profiles compared to those in HbA-bearing adult red cells. In conjunction with the previously discovered O2 dependence of K+ transport in HbF-rich fetal cells, they moreover argue against linkage between different, physiologically relevant, O2-dependent red cell functions.     

Living high–training low: effect on erythropoiesis and maximal aerobic performance in elite Nordic skiers

The “living high–training low” model (Hi–Lo) may improve aerobic performance in athletes, and the main mechanism of this improvement is thought to be augmented erythropoiesis. A positive effect of Hi–Lo has been demonstrated previously by using altitudes of 2,000–3,000 m. Since the rate of erythropoiesis is altitude-dependent, we tested whether a higher altitude (3,500 m) during Hi–Lo increases erythropoiesis and maximal aerobic performance. Nordic skiers trained for 18 days at 1,200 m, while sleeping at 1,200 m in ambient air (control group, n = 5) or in hypoxic rooms (Hi–Lo, n = 6; 3 × 6 days at simulated altitudes of 2,500, 3,000 and finally 3,500 m, 11 h day⁻¹). Measurements were done before, during (blood samples only) and 2 weeks after the intervention (POST). Maximal aerobic performance was examined from and time to exhaustion (T _exh) at (minimum speed associated with ), respectively. Erythropoietin and soluble transferrin receptor responses were higher during Hi–Lo, whereas reticulocytes did not change. In POST (vs. before): hematological parameters were similar to basal levels, as well as red blood cell volume, being 2.68 ± 0.83 l (vs. 2.64±0.54 l) in Hi–Lo and 2.62±0.57 l (vs. 2.87 ± 0.59 l) in controls. At that time, neither nor T _exh were improved by Hi–Lo, being non-significantly decreased by 2.0% (controls) and 3.7% (Hi–Lo). The present results suggest that increasing the altitude up to 3,500 m during Hi–Lo stimulates erythropoiesis but does not confer any advantage for maximal O₂ transport.     

胃癌患者红细胞与白细胞免疫功能的相关性研究

胃癌患者红细胞与白细胞免疫功能的相关性研究郭峰，李淑德，谢苏庆，沈茜第二军医大学附属长海医院免疫室上海２００４３３摘要＊８本文表明胃癌患者红细胞与白细胞免疫功能明显低于良性胃病患者（Ｐ＜０．０１）。胃癌根治术后及中药治疗（如云芝多糖）能促进红细胞免疫...     

Establishment and characterization of a new human clear-cell sarcoma cell-line,HS-MM

We have established and morphologically characterized a new human clear-cell sarcoma cell-line, HS-MM, from the pleural effusion of a 39-year-old man with pulmonary metastasis derived from the primary popliteal tumour. The HS-MM cells were round or spindle-shaped, with round nuclei containing extremely prominent nucleoli. Light microscopically, the heterotransplanted nude mouse tumours showed essentially the same features as those of the original sarcoma, revealing an alveolar pattern of tumour cells with abundant clear cytoplasm. Both in vitro and in vivo, the cells reacted with anti-S-100 protein and melanoma-specific HMB 45 antibodies by immunohistochemistry. Ultrastructurally, the cells contained round euchromatin-rich nuclei with large nuclcoli revealing conspicuous nucleolonema, and a large amount of glycogen and a few lysosomal dense bodies, but no premelanosomes in their cytoplasm. The HS-MM cell line was thus fully proven to exhibit the unique characteristics of a clear cell sarcoma both in vitro and in vivo, being also compatible with an amelanotic melanoma. This cell line will therefore be extremely useful for clinicopathological and histogenetic studies on clear cell sarcomas.     

Increase in capillary blood flow and relative haematocrit in rabbit skeletal muscle following acute normovolaemic anaemia

The effect of acute normovolaemic haemodilution on microvascular red blood cell flow was studied by intravital microscopy in the tenuissimus muscle of the rabbit. Blood was substituted isovolaemically with equal volumes of a 6% solution of dextran 70 (MW 70,000). The systemic haematocrit (H_sys) decreased from 36 ± 4% (mean ± SD) to 17 ± 2%. Following haemodilution capillary haematocrit (H_cap), as measured by video densitometric methods, decreased by 20 ± 9%. The reduction of H_cap was significantly smaller than that of H_sys and H_cap normalized with respect to H _sys increased from 0.39 ± 0.07 in the control situation to 0.62 ± 0.18 after haemodilution. Red blood cell velocity (v_rbcr) increased by 45 ± 20 % and compensated for the decrease in H_cap in such a way that the red blood cell flux, calculated from v_rbc and H_cap remained unchanged. Measurements of volume flow in the feeding arterioles in the muscle revealed a fractional redistribution of blood flow in favour of the muscle capillaries following haemodilution at the expense of vessels in adjacent connective tissue supplied by the same arterioles. This fractional flow redistribution was likely the basis for the relative increase in capillary haematocrit seen after haemodilution. The present data demonstrate that an acute reduction of the systemic haematocrit is compensated for in an active regulating vascular bed by a proportionally smaller decrease in capillary haematocrit and by an increased capillary red cell velocity. Microvascular haematocrit was found not to be a constant fraction of the systemic value, which supports the view of capillary haematocrit as a ‘controlled’ physiological variable.     

Evaluation of heat-damaged and EgG-coated red cells for testing reticuloendothelial function

In vitro methods for standardising and assessing the reproducibility of reticuloendothelial function tests in man were performed. Variation in the degree of heat-induced red blood cell damage could be detected by both Channelyzer plots and a filtration test of red cell plasticity although the former test was less sensitive and difficult to quantitate. In a consecutive study of the clearance of heat-damaged red blood cells (HDRBC) in 8 patients and 2 normal individuals, consistent changes were demonstrated by both assays although occasionally one assay alone provided inconclusive results. When undamaged red cells were coated with IgG anti-D antibodies, the number of IgG molecules bound per red cell was determined by an indirect antiglobulin radioimmunoassay. With this assay, it was shown that the rate of clearance of coated cells was related to the amount of cell bound IgG anti-D. Some variation in the degree of coating of cells from patients with systemic lupus erythematosus was found although the differences were insufficient to account for the reported reduction in the clearance of IgG-coated cells in patients with this disease. The radioimmunoassay and microhaemagglutination techniques revealed that neither IgG, Clq, C3 or C3d were bound to HDRBC following incubation in autologous serum suggesting that these cells were cleared in vivo by mechanisms unrelated to immune receptor recognition.     

驻极体对烫伤大鼠心肌损伤和血液流变指标的修复研究

目的:研究驻极体对烫伤大鼠心肌损伤和血液流变学指标的修复作用。方法:将大鼠随机分成对照组、烫伤组和驻极体治疗组,分别测量对照组、烫伤组和驻极体治疗组大鼠血压、全血粘度和红细胞电泳率的变化。结果:大鼠烫伤后的全血粘度较对照组呈显著性提高,红细胞电泳率和颈动脉血压较对照组均有明显下降。负极性驻极体作用烫伤大鼠后,其血液粘度较烫伤组明显下降,而红细胞电泳率和颈动脉血压较烫伤组有明显上升。结论:负极性驻极体不仅对烫伤大鼠的心肌损伤有积极的修复作用,而且能通过修复红细胞的驻极态来改善烫伤大鼠的血液流变学指标。     

Effects of red blood cell hyperaggregation on the rat microcirculation blood flow

This study presents the effects of red blood cell (RBC) hyperaggregation on the blood flow and pressure in the rat mesentery and cremaster network. We exclusively studied in situ non-vasodilated organs, in order to maintain the physiological regulation mechanisms. Dextran 500 was injected at different concentrations to increase RBC aggregation. The aggregation rate was measured on very small blood samples with an erythroaggregameter (SEFAM) which evaluated the disaggregating shear stress (τ_D ) needed to break the RBC aggregates. Microscopic observations and laser Doppler velocimetry were used to quantify the flow rate. The plasmatic dextran concentration (C) increase had different correlated effects: for example, τ_D increased from 3 dynes cm^?2 (for the control sample) to 14 dynes cm^?2 (for C = 75 μM L^?1); the flow rate was reduced threefold and very large aggregates were observed in the venules; the arteriolar pressure increased while venular pressure decreased. In order to differentiate the effects of RBC hyperaggregation from those of plasma hyperviscosity (due to dextran 500) on microcirculatory blood flow, we injected an RBC antiaggregating drug (troxerutine) (50 or 100 mg kg^?1 IV). The consequences were a high reduction for (τ_D ) (from 14 dynes cm^?2–9 dynes cm^?2), smaller aggregates and higher blood flow in the venules. No effect of troxerutine was observed on plasma viscosity (plasma control: 1,9 cP with or without troxerutine; plasma with dextran at C = 75 μM L^?1: 2,45 cP with or without troxerutine). The results strongly suggest that RBC aggregation has a significant influence on blood flow rate in the microcirculatory network.     

Hydraulic conductivity of the endothelial and outer layers of the rabbit aorta.

Pressure-driven fluid flow across the arterial wall was measured to determine wall hydraulic conductivity (Lp) before and after removal of the endothelium. The thoracic aortas of rabbits, anesthetized with Nembutal, were cannulated, perfused with oxygenated Ringer solution, and removed. With one cannula connected to a capillary manometer and the other closed, the manometer meniscus shift could be used as an indication of fluid loss through the wall plus vessel volume increase (creep). The latter effect, when measured, accounted for about one-fourth of the total volume displacement. The Lp given in cm/(s.cmH2O) +/- SD, was 3.30 +/- 0.96 x 10(-8). Another method employed continuous weighing of a closed aortic segment to obtain fluid loss, and yielded an Lp of 4.07 +/- 1.3 x 10(-8), and after mechanically removing the endothelium, the Lp became 7.73 +/- 2.8 x 10(-8). Using the above data, an Lp could be calculated for aortic endothelium of 8.6 x 10(-8). This suggests that about half the total transmural pressure drop occurs across the endothelium. Scanning electronmicrographs were used to check the condition of the endothelium.