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1.
Fluorescence spectroscopic methods were used to investigate and compare the properties of erythrocyte membranes from individuals with Huntington's Disease (HD) and from normal individuals. Erythrocyte ghosts were labeled with four different fluorescent probes: 1,6-diphenylhexatriene (DPH); 6-lauroyl-2-(dimethylamino)-naphthalene (Laurdan); 2-(4-maleimide anilino)-naphthalene-6-sulfonic acid (MIANS) and 5-(iodoacetamidoethyl)aminoaphthalene-1-sulfonic acid (IAEDANS). DPH is sensitive to the microviscosity of the membranes. Laurdan is highly sensitive to the polarity and relaxation time of its environment. MIANS and IAEDANS both react covalently with sulfhydryl groups in membrane proteins. Erythrocyte membranes were labeled separately with each of these four probes, and we measured the centers of gravity of the fluorescence emission, the fluorescence anisotropies, and the fluorescence lifetimes. In 10 separate experiments, including a total of 24 patients and 14 control individuals, we found no significant differences between the two groups for any of the probes or spectral parameters. These results do not support the existence of a "generalized membrane defect" in individuals with HD.  相似文献   

2.
A laser tweezer technique based on single and/or dual-laser beams is proposed as a biophotonic tool to trap single cells and investigate their biophysical and biomechanical characteristics. Optical deformability and changes in size and cellular morphology of living and nonliving cells can be measured using the proposed technique. Representative results of red blood cell (RBC) optical deformability of 20 homozygous patients with sickle cell disease, including follow-up patients after treating with hydroxyurea (HU) for at least 3 months and 20 healthy control groups, are presented and compared. Shape recovery of deformed RBCs and relaxation time are recorded for each RBC. Results showed that healthy blood and patients treated with HU demonstrate significantly higher optical deformability and degree of optical elongation with morphological change of RBCs than untreated patients. Moreover, the healthy control group and patients treated with HU exhibited faster relaxation time for RBCs than untreated patients. A trapping power that reaches 180 mW caused no observable photo-damage at a wavelength 1064 nm.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12551-021-00790-0.  相似文献   

3.
The uptake of l-leucine by trout red blood cells and peripheral lymphocytes has been analyzed. The present study shows two functionally different Na+-independent systems for apolar branched-chain amino acids. They are designated as L systems because they share some properties with the mammalian L system. The carrier present in red blood cells has low K m values, is trans-stimulable and not stereospecific for leucine uptake; on the other hand, the system present in lymphocytes is stereospecific for leucine uptake and trans-inhibitable. Both carriers are pH sensitive in a similar fashion at low pHs, but there are important differences at higher pH values (above neutrality). These properties are compared with these of the asc systems previously reported in these cells. Received: 2 June 1995/Revised: 7 March 1996  相似文献   

4.
目的:探索红细胞分布宽度(RDW)与ICU院内感染的相关性。方法:根据2001年卫生部颁布的医院感染诊断标准,筛选出2011年1月至2013年12月在ICU住院发生院内感染的224例患者,与同期在ICU住院未发生院内感染的患者232例,收集相关临床资料[年龄、性别、既往合并高血压、冠心病史、慢性病(APACHEⅡ)评分、住院时间、预后]及RDW等实验室指标(连续收集入ICU前三天的实验指标取平均值),分析RDW与院内感染发生的相关性。结果:与对照组RDW(12.18±1.08)%相比,院内感染组RDW(13.52±2.01)%明显升高,差异有统计学意义(P0.01)。多因素logistic回归分析显示,RDW是院内感染的独立预测因素(OR=4.75,95%CI:3.27~6.91,P0.01)。RDW界值为12.81%,RDW的ROC曲线下面积为(0.76±0.02)%,95%CI:0.71~0.80,诊断院内感染的敏感性为56.65%,特异性为85.75%。结论:RDW与ICU院内感染独立相关,是ICU院内感染的独立预测因素。  相似文献   

5.
《Free radical research》2013,47(5):297-304
The redox state of red blood cell components was found to have profound effects on the specific inactivation of erythrocyte glutathione (GSH) peroxidase by divicine, a hydroquinone imine molecule of fava beans likely to be responsible, through redox cycling, of the oxidative damage of red blood cells ultimately resulting in the hemolysis of favism. Oxidation of hemoglobin is a necessary step for the inactivation to take place, apparently as a H2O2-MetHb adduct. On the other hand, the presence of either reduced NADP or glutathione enhances the inactivating effect although NADPH inhibits the oxidation of hemoglobin, and this suggests a catalytic role for MetHb in the inactivation process.  相似文献   

6.
弱激光的生物学效应及对红细胞变形性的改善作用   总被引:10,自引:0,他引:10  
简要叙述激光生物效应和弱激光生物刺激作用。概括阐述激光照射血液所产生的生物学效应,叙述了弱激光对红细胞变形性的改善作用并探讨其可能的作用机理。  相似文献   

7.
8.
湘西土家族、苗族红细胞血型的分布   总被引:6,自引:0,他引:6  
对湖南吉首市的中学生进行了红细胞备型分布调查。土家族200人的各表型人数是:O 57,A 74,B 45,AB 24;M 75,MN 88,N 37;CCDee 84,CCDE 26,DcDee 26,CcDE 47,ccDee 1,ccDE 14,Ccdee 1,CcdE 1;P1(+)103,P1(-)97。苗族202人的各表型人数是:O 74,A 65,B 54,AB 9;M 75,MN 101,N 26;CCDee 78,CCDE 2,CcDee 42,CcDe 58,ccDee 2,ccDE 20;P1(+)65,P1(-)138;Fy(a+b-)199。Fy(a+b+)1,Fy(a-b+)2。 The distribution of several red cell blood group systems was studied in Tujia and Miao ethnic groups in Jishou City,Hunan Province.The phenotype distribution of 200 unrelated Tujias was:O 57,A 74,B 45,AB 24;M 75,MN 88,N 37;CCDee 84,CCDE 26,DcDee 26,CcDE 47,ccDee 1,ccDE 14,Ccdee 1,CcdE1;P1(+)103,P1(-)97。  相似文献   

9.
高斯光束中细胞横向受力分析   总被引:1,自引:0,他引:1  
按照几何光学的原理建立了高斯光束中细胞受力的力学模型,并利用数值计算,得到了细胞偏离光轴受到的向轴回复力大小与细胞的离轴距离X0、直径2R等的关系.结果表明高斯光束对大小不同的细胞有相同的光学势阱宽度,对较大细胞势阱较深所以较容易稳定俘获.讨论了光钳设计中注意的问题.  相似文献   

10.
目的:为制定中国中年女性红细胞计数正常参考值的统一标准提供科学依据.方法:收集了中国331个单位用显微镜计数法测定的41003例中年女性红细胞计数正常参考值,运用相关分析和回归分析的方法,研究了其与八个地理因素的关系.结果:发现中年女性红细胞计数正常参考值与中国地理因素之间有很显著的相关关系(F=364.76,P=0.000).用逐步回归分析的方法推导出了一个回归方程:Y^=4.184+0.0002421X1-0.02921X4+0.0002582X7+0.08144X8±0.47.结论:如果知道了中国某地的地理因素,就可以用回归方程计算这个地区的红细胞计数正常参考值.依据红细胞计数正常参考值与地理因素的依赖关系,把中国分为八个区.  相似文献   

11.
目的:研究红细胞体积分布宽度(RDW)对心力衰竭患者病情及预后转归的评估价值。方法:将我院心内科收治的110例心力衰竭患者(研究组)根据病情分为NYHAⅡ级30例、Ⅲ级46例、Ⅳ级34例,另选择同期健康体检者110例作为对照组。同时根据患者6个月内预后情况分为存活组(91例)和死亡组(19例)。比较分析各组患者RDW水平、死亡率,采用单因素和多因素logistic回归分析心力衰竭预后的影响因素。结果:研究组中,NYHAⅢ~Ⅳ级患者RDW水平明显高于对照组,且随着NYHA分级的增加,RDW水平明显升高(P0.05)。NYHAⅣ级患者死亡率明显高于NYHAⅡ、Ⅲ级患者(P0.05)。与死亡组比较,存活组年龄明显较小,入院时Hcy、CRP、GLU、RDW、NT-pro BNP明显降低,Hb、RBC、LVEF水平明显升高(P 0.05)。年龄、入院时NT-pro BNP和RDW是心力衰竭的独立危险因素,而LVEF水平是独立保护因素(P0.05)。结论:RDW可反映心力衰竭患者的病情严重程度,对于预后转归评估具有重要指导意义。  相似文献   

12.
The use of optical trap and microbeam for investigating mechanical and transport properties of inter cellular tunneling nanotubes (TnTs) in tumor spheroids has been demonstrated. TnTs in tumor spheroids have been visualized by manipulating TnT connected cells using optical tweezers. Functionality of the TnTs for transferring cytoplasmic vesicles and injected dye molecules by optoporation method has been studied. Further, the TnTs could be longitudinally stretched by manipulating the connected cells and their elastic response was studied.

Manipulation of cells at the surface of tumor spheroid using optical tweezers and injection of fluorescent dye into a trapped cell using optoporation technique.  相似文献   


13.
目的:探讨高原地区高血压患者红细胞指标和血清高迁移率族蛋白2(HMGB2)与颈动脉粥样硬化的相关性。方法:本研究共纳入244例高原地区高血压患者,通过检测颈动脉内膜中层厚度(IMT)分三组:内膜正常组(0.8 mm≤IMT1.0 mm);内膜增厚组(1.0 mm≤IMT1.2 mm);斑块形成组(IMT≥1.2 mm)。收集患者的临床资料,检测患者红细胞指标和血清HMGB2水平及其他生化指标。通过分析IMT与各项指标之间的相关性,评价颈动脉硬化的相关因素。结果:三组间红细胞压积(HCT)、红细胞计数(RBC)、红细胞分布宽度(RDW)、血清HMGB2水平差异均具有统计学意义(均P0.05)。相关分析结果显示,RBC(r=0.368)、HCT(r=0.409)、RDW(r=0.596)、HMGB2(r=0.291)与IMT呈正相关(均P0.05)。多因素Logistic回归分析显示RBC、HCT、RDW、HMGB2是颈动脉硬化的独立危险因素。结论:高原地区高血压患者RBC、HCT、RDW、HMGB2水平与IMT密切相关,且RBC、HCT、RDW、HMGB2水平升高是颈动脉硬化发生的危险因素,可作为动脉硬化早期预测因子。  相似文献   

14.
Considering its complex molecular pathophysiology, beta-thalassemia could be a good in vivo model to study some aspects related to erythrocyte functions with potential therapeutic implications not only within the frame of this particular hemoglobinopathy but also with respect to conditions in which the cellular milieu, altered by a deranged anion exchanger, could display a significant pathogenetic role (i.e., erythrocyte senescence, complications of red cell storage, renal tubular acidosis and some abnormal protein thesaurismosis). This work evaluates the anionic influx across band 3 protein in normal and beta-thalassemic red blood cells (RBCs) and ghosts. Since redox-mediated injury is an important pathway in the destruction of beta-thalassemic RBCs, we studied the anion transport and the activity of caspase 3 in the absence and presence of t-butylhydroperoxide in order to evaluate the effect of an increase of cellular oxidative stress. Interestingly, beta-thalassemic erythrocytes show a faster rate of anion exchange than normal RBCs and absence of any modulation mechanism of anion influx. These findings led us to formulate a hypothesis about the metabolic characteristics of beta-thalassemic erythrocytes, outlining that one of the main targets of caspase 3 in RBCs is the cytoplasmic domain of band 3 protein.  相似文献   

15.
纳西族和普米族的红细胞血型分布   总被引:2,自引:0,他引:2  
肖春杰  张卫红 《遗传学报》1995,22(4):252-257
调查了云南纳西族和普米族各104人的ABO、NMSs、Rh和P血型系统。结果表明,ABO血型系统中,纳西族和普米族有较高的基因频率r,分别为0.6082和0.6882,且基因频率p=q,纳西族均为0.1959,普米族均为0.1559。MNSw系统中两个民族都表现m〉n、s〉s,Ms〉Ns、MS〉NS,其中纳西族的基因频率在国内报道的相应值中是比较高的,且NS为零。  相似文献   

16.
以人子宫颈癌细胞株HeLa为对象,采用免疫印迹、流式细胞光度术和间接免疫荧光.流式细胞光度术等方法,分析三尖杉酯碱对细胞增殖周期、凋亡等的影响,并检测着丝粒蛋白CenpB基因表达的水平,进一步分析它与细胞增殖的关系及三尖杉酯碱的作用效应。结果表明:0.2μg/mL三尖杉酯碱作用时间的延长带来HeLa细胞G1期缩短、S期延长的时相变化趋势,与之相关的是G2期向G1期过渡的缓慢延迟;凋亡率呈现增加的趋势;相对于未处理的对照细胞,0.2μg/mL三尖杉酯碱的作用使CenpB蛋白表达水平降低,但不呈简单的时间函数关系,这可能是细胞周期检验点应对药物诱导作用的反馈调节的体现,而重要着丝粒结构蛋白CenpB的基因表达调节与之可能有明显的相关性。  相似文献   

17.
目的:研究回生口服液对晚期非小细胞肺癌患者血浆纤维蛋白原和血小板水平的影响。方法:选取2011 年1 月至2013 年7 月已被收治的112 例晚期非小细胞肺癌患者按照知情同意原则随机分为治疗组(60 例)和对照组(52 例)两组,治疗组在支持、对 症治疗的基础上口服回生口服液治疗,对照组仅给予支持、对症治疗,4 周后观察两组患者经两种不同的治疗方案治疗后患者血 浆纤维蛋白原及血小板水平变化。结果:治疗组经给药治疗后血浆纤维蛋白原及血小板水平与治疗前相近,差异均无统计学意义 (P>0.05);对照组经治疗后血浆纤维蛋白原及血小板水平较治疗前高,差异均有统计学意义(P<0.05);治疗组给药治疗后血浆纤 维蛋白原及血小板水平均较对照组低,差异均有统计学意义(P<0.05)。结论:回生口服液可能是通过降低血浆纤维蛋白原及血小 板的含量从而改善晚期非小细胞肺癌患者的血液高凝状态。  相似文献   

18.
目的:研究回生口服液对晚期非小细胞肺癌患者血浆纤维蛋白原和血小板水平的影响。方法:选取2011年1月至2013年7月已被收治的112例晚期非小细胞肺癌患者按照知情同意原则随机分为治疗组(60例)和对照组(52例)两组,治疗组在支持、对症治疗的基础上口服回生口服液治疗,对照组仅给予支持、对症治疗,4周后观察两组患者经两种不同的治疗方案治疗后患者血浆纤维蛋白原及血小板水平变化。结果:治疗组经给药治疗后血浆纤维蛋白原及血小板水平与治疗前相近,差异均无统计学意义(P〉0.05);对照组经治疗后血浆纤维蛋白原及血小板水平较治疗前高,差异均有统计学意义(P〈0.05);治疗组给药治疗后血浆纤维蛋白原及血小板水平均较对照组低,差异均有统计学意义(P〈0.05)。结论:回生口服液可能是通过降低血浆纤维蛋白原及血小板的含量从而改善晚期非小细胞肺癌患者的血液高凝状态。  相似文献   

19.
Infrared laser traps (optical tweezers) were used to study laser-induced organelle movements in the marine alga Pyrocystis noctiluca (Dinophyta). These cells are highly suitable for optical micromanipulation due to their large size and extensive vacuole. Experiments were done with plastids held by optical tweezers and moved from the nuclear area into the vacuole. The subsequent retraction movement was analysed for speed. The displaced organelles remained connected to their original position by a thin cytoplasmic strand, often less than 1 μm in diameter. When the organelles were released they rapidly returned at an initial rate of 81.7 ± 7.8 μm . s?1 (overall displacement 50 μm, measured distance 20 μm, 25 °C ± 1 °C, number of cells 22), slowing down with progressive retraction of the connecting strand. The return movement was reduced to 4.2 ± 0.2 μ .s?1 (n = 10) when the organelles were displaced and held for 1 min. Displacement to a longer distance increased the rate of return movement. A change from a high to a low environmental temperature significantly reduced movement from 94.5 ± 9.0 . s?1 (30 °C ± 1 °C, n = 22) to 34.5 ± 2.7 μm .s?1 (5°C ± 1 °C, n = 22). Nocodazole and N-ethylmaleimide (NEM), inhibitors of microtubules and acto-myosin, respectively, did not affect the retraction of the connecting strand, but at high concentrations of NEM it became increasingly difficult to move organelles away from the nuclear area. We suggest that the return movement of organelles within laser-induced artificial strands mainly depends on the viscoelastic properties of the tonoplast. The quantification of these properties by optical tweezers allows determination of reactions of plant cells to temperature changes.  相似文献   

20.
Myosins generate force and motion by precisely coordinating their mechanical and chemical cycles, but the nature and timing of this coordination remains controversial. We utilized a FRET approach to examine the kinetics of structural changes in the force-generating lever arm in myosin V. We directly compared the FRET results with single-molecule mechanical events examined by optical trapping. We introduced a mutation (S217A) in the conserved switch I region of the active site to examine how myosin couples structural changes in the actin- and nucleotide-binding regions with force generation. Specifically, S217A enhanced the maximum rate of lever arm priming (recovery stroke) while slowing ATP hydrolysis, demonstrating that it uncouples these two steps. We determined that the mutation dramatically slows both actin-induced rotation of the lever arm (power stroke) and phosphate release (≥10-fold), whereas our simulations suggest that the maximum rate of both steps is unchanged by the mutation. Time-resolved FRET revealed that the structure of the pre– and post–power stroke conformations and mole fractions of these conformations were not altered by the mutation. Optical trapping results demonstrated that S217A does not dramatically alter unitary displacements or slow the working stroke rate constant, consistent with the mutation disrupting an actin-induced conformational change prior to the power stroke. We propose that communication between the actin- and nucleotide-binding regions of myosin assures a proper actin-binding interface and active site have formed before producing a power stroke. Variability in this coupling is likely crucial for mediating motor-based functions such as muscle contraction and intracellular transport.  相似文献   

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