Functional recovery after human umbilical cord blood cells transplantation with brain-derived neutrophic factor into the spinal cord injured rat

Summary There have been many efforts to recover neuronal function from spinal cord injuries, but there are some limitations in the treatment of spinal cord injuries.The neural stem cell has been noted for its pluripotency to differentiate into various neural cell types. The human umbilical cord blood cells (HUCBs) are more pluripotent and genetically flexible than bone marrow neural stem cells. The HUCBs could be more frequently used for spinal cord injury treatment in the future.Moderate degree spinal cord injured rats were classified into 3 subgroups, group A: media was injected into the cord injury site, group B: HUCBs were transplanted into the cord injury site, and group C: HUCBs with BDNF (Brain-derived neutrophic factor) were transplanted into the cord injury site. We checked the BBB scores to evaluate the functional recovery in each group at 8 weeks after transplantation. We then, finally checked the neural cell differentiation with double immunofluorescence staining, and we also analyzed the axonal regeneration with retrograde labelling of brain stem neurons by using fluorogold. The HUCBs transplanted group improved, more than the control group at every week after transplantation, and also, the BDNF enabled an improvement of the BBB locomotion scores since the 1 week after its application (P<0.05). 8 weeks after transplantation, the HUCBs with BDNF transplanted group had more greatly improved BBB scores, than the other groups (P<0.001). The transplanted HUCBs were differentiated into various neural cells, which were confirmed by double immunoflorescence staining of BrdU and GFAP & MAP-2 staining. The HUCBs and BDNF each have individual positive effects on axonal regeneration. The HUCBs can differentiate into neural cells and induce motor function improvement in the cord injured rat models. Especially, the BDNF has effectiveness for neurological function improvement due to axonal regeneration in the early cord injury stage. Thus the HUCBs and BDNF have recovery effects of a moderate degree for cord injured rats.     

人脐血来源内皮祖细胞的纯化鉴定及定向分化的研究

目的 检测CD133^＋血管内皮祖细胞（EPC）的细胞表面标志物，鉴定其生物学特性。方法 采用免疫磁珠法分离人脐血EPC，用EGM-2MV培养基[含表皮生长因子（EGF）、血管内皮生长因子（VEGF）、成纤维细胞生长因子（FGF）2等具有诱导分化作用的细胞因子]进行体外培养。应用流式细胞术、免疫组织化学等方法检测CD133^＋细胞的比例、原代EPC的生长曲线及生长特性。透射电镜查找Weibel-Palade小体。同时设计EPC裸鼠成瘤实验，观察瘤体生长及血管增生情况，以鉴定EPC的生物学特性。结果 CD133^＋细胞在免疫磁珠分离前后的比例各为0．91％及85．52％。EPC原代培养时细胞形态正常、密度均匀，前3d为相对抑制期，此后快速增殖，10d后达80％～90％融合。EPC生长曲线显示，接种后5d内细胞数量无明显变化，从第7天开始明显增加，第17天达高峰。光学显微镜下可见，原代EPC贴壁后呈梭形，接种后7d数量明显增加，呈克隆状生长。透射电镜观察到，细胞膜伸出许多伪足丝，基底膜呈多层；细胞质内可见一种短棒状小体，含平行管状的内部结构，即Weibel-Palade小体，确定其为EPC。裸鼠成瘤实验可见EPC组肿瘤瘕体及血管数量大于或多于对照组；抗人血管性假血友病因子（vWF）免疫荧光染色显示，大量EPC参与肿瘤血管生成。结论本实验分离培养的CD133^＋细胞具有分化为成熟血管内皮细胞的能力，即为EPC。裸鼠成瘤实验初步证明EPC参与血管重建，具有促进血管新生、加速缺血组织血管化的作用。     

人脐血来源内皮祖细胞促进裸鼠皮瓣存活的实验研究

目的将内皮祖细胞（endothelial progenitor cell，EPC）引入皮瓣缺血组织中，初步研究其生物学特性及在皮瓣缺血组织中促血管发生的作用。方法采用免疫磁珠法从人脐血中分离培养CD133＋内皮祖细胞，将体外扩增的EPC局部注射于裸鼠超长皮瓣模型中，观察EPC转归及参与皮瓣血管重建的情况；通过观察皮瓣坏死面积及微血管增生情况，评价EPC在皮瓣缺血组织中再血管化能力。结果EPC组皮瓣坏死面积明显小于空白组（P〈0．05）、真皮下层组织灌流量大于对照组（P〈0．05）；荧光示踪及免疫组织化学染色证实EPC参与皮瓣血管重建。结论EPC参与血管重建，具有促进血管新生，加速缺血组织血管化的作用。     

脐血间充质干细胞的培养鉴定及成骨诱导后的免疫原性研究

目的通过观察体外培养人脐血间充质干细胞(Umbilical cord blood-mesenchymal stem cells,UCB-MSCs)并作诱导成骨分化,探讨其作为组织工程的骨种子细胞的可行性。方法体外分离培养UCB-MSCs,流式细胞仪检测细胞表面抗原的表达及其变化规律;体外成骨诱导UCB-MSCs2周,采用Alizarin Red染色和钙离子半定量测定的方法评价细胞成骨活性。取P2代UCB-MSCs细胞,流式细胞仪检测加入IFN-γ前后的HLA-Ι、HLA-Ⅱ、CD40、CD80等分子的表达情况;流式细胞仪检测UCB-MSCs在成骨诱导分化前后HLA-Ι类分子、HLA-Ⅱ类分子的表达情况以观察成骨诱导分化的MSCs免疫抗原性的变化。结果第1、3、5代细胞的CD29、CD105和CD166均呈阳性表达,而造血细胞系的表面标记CD31、CD34和CD45则呈低表达,且随传代次数增加含量逐渐下降。UCB-MSCs成骨诱导2周后,Alizarin Red染色为阳性。对照组则无明显钙盐沉积。钙离子半定量的检测结果则表明,UCB-MSCs成骨诱导2周后的钙离子含量远高于未诱导组。流式细胞检测结果显示,人UCB-MSCs高表达HLA-Ι类分子,不表达HLA-Ⅱ类分子和CD40,CD80等共刺激分子;经IFN-γ刺激诱导后,HLA-Ι类分子的表达未发生改变,HLA-Ⅱ类分子呈阳性表达,而CD40和CD80的表达仍为阴性。人UCB-MSCs在成骨诱导分化前后HLA-Ι类分子均为阳性表达;而HLA-Ⅱ类分子在成骨分化前为阴性,诱导后阳性表达率增高。结论①UCB-MSCs能诱导分化为成骨细胞,有望成为较理想的组织工程骨种子细胞;②成骨分化使UCB-MSCs的免疫原性发生相应变化。     

人脐血内皮祖细胞治疗裸鼠心肌梗死

目的 探讨人脐血内皮祖细胞(EPCs)移植治疗裸鼠心肌梗死的可行性.方法 采用淋巴细胞分离液提取人脐血单个核细胞(MNCs),应用添加诱导因子的培养基于体外诱导分化并于培养7 d后进行鉴定.采用20只裸鼠建立心肌梗死模型后,将体外诱导分化7 d并摄取CM-Dil的内皮祖细胞通过尾静脉注射进行细胞移植到实验组,对照组注射培养基.2周后计数心梗区域新生毛细m管密度及心梗面积并于荧光显微镜下观察新生血管的荧光.结果 体外诱导7 d后贴壁细胞CD34阳性率达(50.48±5.17)%,CDl33阳性率达(19.12±4.37)%.实验组平均梗死面积为(8.27±1.64)%,对照组为(14.30±2.84)%(t=-4.78,P<0.05);实验组每高倍视野平均新生血管密度为14.29±1.38,对照组为10.17±1.72(t=4.71,P<0.01);行荧光显微镜下观察实验组新生血管有红色荧光.讨论人脐血单个核细胞在体外诱导分化为内皮祖细胞,进行细胞移植到建立心梗模型的裸鼠后可在心梗区域形成新生血管,从而并改善梗死部位心脏功能.     

韩国脐血移植和脐血库的现状（附视频）

自1996年韩国完成首例脐血移植后,各大医院陆续开展了该项技术并建立起脐血库。本讲座介绍了韩国儿童脐血移植的现状、静脉输注冻存的自体脐血单个核细胞改善脑瘫儿童神经功能的试验以及韩国脐血库建设情况和脐血移植的选择策略。     

TRH对大鼠脊髓损伤后SCBF和SEP的影响

脊髓损伤（ＳＣＩ）后内源性阿片肽释放，并参与脊髓的继发损伤机制。ＴＲＨ可阻断阿片肽的自主神经效应，而不影响痛觉。本实验探讨大剂量ＴＲＨ（２ｍｇ／ｋｇ／ｈ）治疗对大鼠脊髓打击伤（Ａｌｌｅｎｓ法１０ｇｘ５ｃｍ）后脊髓血流量（ＳＣＢＦ）和脊髓诱发电位（ＳＥＰ）的影响。脊髓损伤后１ｈ，ＳＣＢＦ开始显著下降，持续至伤后２４ｈ，ＳＥＰ峰潜时呈进行性延长趋势；伤后即刻静脉注射ＴＲＨ（２ｍｇ／ｋｇ／ｈ，共５次），可使伤后即刻和２４ｈ的ＳＣＢＦ显著升高，并使伤后ＳＣＢＦ下降时间延迟３ｈ，同时ＳＥＰ峰潜时有不同程度改善。结果表明，ＴＲＨ对受伤脊髓早期有一定的防治作用，并具有一定的后发效应；同时也可促进脊髓的神经传导功能。本文亦对ＴＲＨ治疗ＳＣＩ的病理生物学机制进行了讨论。     

Parameters influencing augmentation of cerebral blood flow by cervical spinal cord stimulation

Summary. Background. Cervical spinal cord stimulation (SCS) has been shown to augment cerebral blood flow (CBF) and protect the brain from focal ischemia. However, the application of SCS in the treatment of cerebral ischemia requires a better understanding of the limits of the cerebrovascular effect and the optimal stimulation parameters. In the present study, we investigated the effects of various stimulation parameters on CBF augmentation, as well as the issue of tachyphylaxis of the CBF response.Methods. SCS was performed in adult Sprague Dawley rats, and CBF was assessed using cortical laser Doppler flowmetry (LDF). In separate experimental series, stimulation amplitude, frequency, and pulse width were varied, and the effect on the LDF response was recorded. Finally, using the stimulation parameters found to elicit the strongest LDF response, we examined the effect of lengthening the period of SCS.Findings. SCS elicited a robust increase in cortical LDF values as previously demonstrated. The magnitude of the response varied in a dose-dependent fashion with the stimulation amplitude. LDF values increased by more than 80% over baseline with an amplitude of 1.5mA. The optimal pulse width and frequency of the stimulation were 0.25ms and 50Hz, respectively. Lengthening the stimulation period up to 20 minutes resulted in a persistent increase in cerebral LDF values during the entire stimulation period, although the magnitude of this effect diminished to approximately 50% over the baseline after 10 minutes.Conclusions. SCS elicits a robust augmentation in CBF, which lasts the entire stimulation duration. Stimulation parameters required for optimal cerebrovascular response are within normally used therapeutic ranges in the clinical settings. These results provide further evidence that SCS may provide a novel therapeutic strategy for the treatment of cerebral ischemia.     

Transplantation of human CD34+ stem cells from umbilical cord blood to rats with thioacetamide-induced liver cirrhosis

BACKGROUND: Liver fibrosis results from accumulation of extracellular matrix components and is associated with many chronic hepatic diseases. There is to date no specific therapy for this disease, and patients receive treatment for its associated complications. Specific progenitor cells, known as oval cells, are present in the liver. As oval cells express markers such as CD34, they are thought to arise from a hematopoietic precursor. The aim of this work was to investigate whether transplantation of hematopoietic CD34(+) stem cells could improve hepatic fibrosis by their differentiation into hepatocytes. METHODS: CD34(+) stem cells from human umbilical cord blood were purified, transduced with a lentiviral vector containing the green fluorescent protein (GFP) gene and injected via portal vein into rats with liver cirrhosis induced by the 4-month administration of thioacetamide. Rats were killed 15 and 60 days post-transplantation. RESULTS: Up to 37% and 22% fluorescent cells were observed in the blood of control and cirrhotic rats, respectively, at 15 days post-transplantation. At 60 days post-transplantation, however, fluorescent cells were completely absent from the blood. Fluorescence was not detected in liver sections at either 15 or 60 days post-transplantation. Polymerase chain-reaction study to detect the GFP gene ruled out silencing of the transgene. CONCLUSIONS: These results suggest that the transplanted cells did not engraft in the liver and were eliminated from the rats.     

脐血间充质干细胞的分离培养鉴定及诱导分化研究

目的：分离培养人脐血间充质干细胞（human umbilical cord blood-derived mesenchymal stem cells,hUCB-MSC）,体外观察其生长特性,并在特定条件下诱导分化,探讨其成脂成骨分化能力.方法：采用沉降法和密度梯度离心结合贴壁培养法自脐血中分离间充质干细胞,倒置显微镜下观察其形态及生长情况;流式细胞仪分析细胞周期并检测细胞表面标志物;用茜素红染色和油红0染色分别鉴定其成骨成脂分化能力.结果：纯化的hUCB-MSC贴壁生长,呈均一梭形,具有较强的增值能力,流式细胞仪分析P3代hUCB-MSC稳定表达间充质干细胞表面抗原标志CD73,CD105和CD90等,不表达造血标志CD34和CD45;成骨诱导后3周后细胞茜素红染色阳性;成脂诱导3周后细胞油红0染色阳性.结论：本实验分离的hUCB-MSC具有较强的增殖能力,表达间充质干细胞的表面标记,具有成骨成脂分化潜能.     

氯化锂体外诱导人脐血间充质干细胞向神经细胞分化的实验研究

目的 探讨氯化锂体外诱导人脐血间充质干细胞(MSCs)向神经细胞分化的可行性.方法 无菌条件下收集正常足月儿的脐带血,肝素抗凝,密度梯度离心法分离人脐血单个核细胞,贴壁法纯化,用含15%FBS的低糖DMEM培养基进行扩增培养,流式细胞仪检测表面抗原.取3代的脐血MSCs进行诱导,A组:用含15%FBS和20 ng/ml bFGF的DMEM完全培养基预诱导24 h,3 mol/L LiCI的DMEM培养基继续诱导6 d:B组:含3 mol/L LiCI的DMEM培养基诱导7 d;C组:含15%FBS的DMEM培养基正常培养7 d.光镜下观察细胞形态,用免疫组化技术检测细胞NSE、MAP2及GFAP的表达.结果 A组与B组诱导3 d后细胞即出现形态学上的改变,细胞变成不规则形,立体感增强,从胞体伸出突起.免疫组织化学和免疫荧光方法鉴定显示,诱导后的细胞能表达神经元特异性标志NSE和MAP2,阳性表达率A组[分别为(73.6±7.8)%,(75.5±8.5)%]明显高于B组[分别为(31.0±4.3)%、(33.5±5.O)%],而星形胶质细胞特异性标志GFAP阳性细胞较少,A、B、C三组阳性表达率分别为(4.7 ±3.3)%、(5.1±4.6)%、(8.5±3.2)%.结论 LiCI联合生长因子bFGF体外可诱导人脐血MSCs分化为神经元样细胞.     

Cultured human epithelium: human umbilical cord blood stem cells differentiate into keratinocytes under in vitro conditions

BACKGROUND: Stem cells have the capacity to renew or to give rise to a specialized cell types. Human umbilical cord blood (HUCB) has been explored as an alternative source of stem cells. However, its potential to differentiate into cells of other tissues is still under discussion. The aim of our study was to evaluate if HUCB stem cells could differentiate into epithelial cells under in vitro conditions. METHODS: Human keratinocytes derived from adult female skin donors, were isolated and cultured on fibrin glue/fibroblast gels-control group. In the umbilical cord blood cell group, male umbilical cord blood cells were added at a 1:10 ratio to keratinocytes and co-cultured on the fibrin glue/fibroblasts gel. After 15 days of culture, the sheets were analyzed by use of histochemistry and FISH. DNA was extracted and evaluated by use of polymerase chain reaction (PCR) for detection of Y-chromosome-specific sequences. RESULTS: In both groups a regular epithelial sheet consisting of three to four layers of cells was formed. Using PCR and FISH, in the umbilical cord blood cell group the presence of Y-chromosome-specific sequences in the cultured keratinocytes could be detected. In the control group, no Y-chromosome-specific sequences could be detected. CONCLUSION: Our findings indicate that umbilical cord blood stem cells differentiate into epithelial cells under in vitro conditions and thereby, might serve as a starting material for isolation and expansion of cells for transplantation in patients with large skin defects.     

Cervical spinal cord stimulation increases cerebral cortical blood flow in an experimental cerebral vasospasm model

Summary Background. Cerebral microcirculatory changes during cerebral vasospasm after aneurysmal subarachnoid haemorrhage (SAH) are still controversial and uncertain. The aim of our study is to demonstrate that spinal cord stimulation (SCS) augments cerebral cortical microcirculatory blood flow in an experimental cerebral vasospasm model by using Laser Doppler Flowmetry (LDF).Method. The experiments were carried out on 24 New Zealand rabbits. Three experimental groups were designed. In group 1, Cerebral cortical blood flow (CCoBF) was evaluated by LDF in 8 rabbits. In group 2, Intracisternal saline injection and cervical epidural electrode placement without SCS were performed in 8 animals before LDF. In group 3, LDF was performed before and after SCS on the 4^th day of SAH in 8 rabbits. CCoBF parameters obtained from LDF data were compared.Findings. The occurrence of vasospasm after SAH was demonstrated with significant changes in LDF values. In all SAH animals, SCS resulted in significant increase (30%) in CCoBF. This increase was observed to continue even after the cessation of the stimulation.Conclusions. These results indicate that SCS improves cortical ischemia due to vasospasm after induced SAH. The cervical SCS may constitute a new therapeutic modality in treating disturbed CCoBF due to vasospasm.     

Hepatocyte differentiation from embryonic stem cells and umbilical cord blood cells

With the development of regeneration medicine, many researchers have attempted hepatic differentiation from nonhepatic-origin cell sources. The differentiation of embryonic stem (ES) cells into hepatocyte-like cells has been reported in several papers. Mouse ES cells have shown a potential to develop into hepatocyte-like cells in vitro on the basis of hepatic gene expression after adding several growth factors. We transplanted cultured embryoid body (EB) cells (male) into female mice. A liver specimen of the recipient was examined by immunohistochemical staining for albumin and fluorescence in situ hybridization for the Y chromosome after transplantation. Both Y chromosome- and albumin-positive cells were recognized in the recipient female liver, and were considered to be hepatocyte-like cells derived from ES cells containing the Y chromosome. Many groups, including ourselves, have studied hepatocyte-like cell differentiation from umbilical cord blood cells (UBCs). We cultured nucleated cells isolated from UBCs. Using immunostaining, ALB-positive and CK-19-positive cells were recognized in the culture. Dual staining of ALB and CK-19 demonstrated that ALB was coexpresed with CK-19, suggesting the existence of hepatic progenitors. In this review, we consider recent studies of the differentiation of hepatocytes from nonhepatic origins, especially ES cells and umbilical cord blood.     

长期培养人胚神经干细胞对兔脊髓损伤的修复作用

[目的]观察长期培养人胚神经干细胞（hNSCs）的体外生长特性与转染EGFP基因后移植治疗兔脊髓横切损伤模型在体内的生物学活性及对神经结构修复和功能恢复的影响。[方法]体外分离、培养并鉴定hNSCs，用逆转录病毒介导的增强绿色荧光蛋白基因（EGFP）进行转染；制备兔T9全横断脊髓损伤模型；观察hNSCs移植对脊髓损伤后神经结构修复和功能恢复的影响。[结果]从胎龄10～20周的新鲜人胚脑皮层中成功分离出神经干细胞，该细胞具有连续克隆传代能力，诱导分化后表达分化细胞的特异抗原。本实验室已成功连续培养10个月（17代），转染EGFP基因后，仍保持未分化状态，能够自我更新形成新的神经球；移植入兔SCI模型后，hNSCs能在体内存活、迁移、分化并增殖。与对照组相比，hNSCs移植组明显促进了脊髓神经的再生、结构的修复和下肢运动功能的恢复。[结论]hNSCs移植促进了脊髓损伤后神经结构的修复和功能的恢复，是治疗急性脊髓损伤的一种有效方法。     

人脐血单个核细胞联合雪旺细胞修复脊髓损伤的实验研究

目的 探讨人脐血单个核细胞(haman cord blood mononuclear cells,HCMNCs)与大鼠雪旺细胞(Schwann cells,SCs)联合移植应用于大鼠脊髓损伤的疗效.方法 健康成年8周龄Wistar雌性大鼠40只,体重(200±30)g.利用Impactor Model Ⅱ型打击器制成T10脊髓损伤模型.40只大鼠随机分成4组,每组10只,即DMEM实验对照组、HCMNCs移植组、SCs移植组、HCMNCs+SCs联合移植组.用HE染色、顺行示踪染色及电镜观察脊髓损伤处轴突再生情况,对各组实验动物脊髓损伤后肢体功能的恢复情况进行行为学评分(BBB评分)及脚印分析实验,综合评估脊髓功能恢复程度.结果 HCMNCs+SCs联合移植治疗能够明显促进神经再生,改善功能,减少空洞形成.BBB评分和脚印分析实验显示各组疗效比较,差异有统计学意义.组织学和电镜观察神经轴突再生情况与功能学检查的结果 相吻合.结论 以分泌各种神经营养因子为特点的SCs为平台,联合移植后诱导HCMNCs向神经元及神经胶质细胞分化,可促进脊髓损伤的恢复.     

人脐血间充质干/祖细胞诱导为心肌样细胞的实验研究

目的　了解脐血间充质干 /祖细胞用于心肌细胞再生的可行性 ,并探讨其最佳的诱导培养条件。方法　将脐血单个核细胞置于低血清 (2 % )DMEM培养基中生成贴壁细胞层 ,依传代方法 ,用相同培养条件进行扩增 ,扩增后的贴壁细胞置入心肌诱导培养液中 ,并添加 5 氮杂胞苷进行诱导分化、采用心肌特异性收缩蛋白 肌钙蛋白T染色鉴定被诱生的心肌样细胞。结果　脐血间充质干 /祖细胞克隆在脐血单个核细胞中出现频率为 0 .5× 10 -6,在传 2 0代时 ,可有效扩增 1.3× 10 7倍 ,诱导后 ,70 %的脐血间充质干 /祖细胞分化为心肌样细胞。结论　采用上述扩增与诱导条件 ,脐血间充质干 /祖细胞可得到有效扩增 ,并可高效向心肌样细胞分化。     

In vitro human cord blood platelet lysate characterisation with potential application in wound healing

Platelets contain abundant growth factors and cytokines that have a positive influence on the migration and proliferation of different cell types by modulating its physiopathological processes. As it is known that human umbilical cord blood platelet lysate (UCB‐PL) contains a supraphysiological concentration of growth factors, in the present study, we investigated its effectiveness in wound‐healing processes. Human UCB‐PL was obtained by the freeze/thaw of platelet concentrate (1.1 × 10⁹ platelets/L), and its effect was evaluated on human or mouse endothelial cells, monocytes, fibroblasts, and keratinocytes in different concentrations. Human UCB‐PL was observed to have high levels of pro‐angiogenic growth factor than peripheral blood platelet‐rich plasma. Among the cell lines, different concentrations of human UCB‐PL were necessary to influence their viability and proliferation. For L929 cells, 5% of total volume was necessary, while for human umbilical vein endothelial cell, it was 10%. Cell migration on monocytes was increased with respect to the positive control, and scratch closure on keratinocytes was increased with respect to serum‐free medium with only 10% of human UCB‐PL. We concluded that the human UCB‐PL may be useful to produce a large amount of standard platelet concentrates sufficient for several clinical‐scale expansions avoiding inter‐individual variability, which can also be used as a functional tool for clinical regenerative application for wound healing.     

Effect of norepinephrine on spinal cord blood flow and parenchymal hemorrhage size in acute-phase experimental spinal cord injury

Purpose

In the acute phase of spinal cord injury (SCI), ischemia and parenchymal hemorrhage are believed to worsen the primary lesions induced by mechanical trauma. To minimize ischemia, keeping the mean arterial blood pressure above 85 mmHg for at least 1 week is recommended, and norepinephrine is frequently administered to achieve this goal. However, no experimental study has assessed the effect of norepinephrine on spinal cord blood flow (SCBF) and parenchymal hemorrhage size. We have assessed the effect of norepinephrine on SCBF and parenchymal hemorrhage size within the first hour after experimental SCI.

Methods

A total of 38 animals were included in four groups according to whether SCI was induced and norepinephrine injected. SCI was induced at level Th10 by dropping a 10-g weight from a height of 10 cm. Each experiment lasted 60 min. Norepinephrine was started 15 min after the trauma. SCBF was measured in the ischemic penumbra zone surrounding the trauma epicenter using contrast-enhanced ultrasonography. Hemorrhage size was measured repeatedly on parasagittal B-mode ultrasonography slices.

Results

SCI was associated with significant decreases in SCBF (P = 0.0002). Norepinephrine infusion did not significantly modify SCBF. Parenchymal hemorrhage size was significantly greater in the animals given norepinephrine (P = 0.0002).

Conclusion

In the rat, after a severe SCI at the Th10 level, injection of norepinephrine 15 min after SCI does not modify SCBF and increases the size of the parenchymal hemorrhage.     

Evidence forin vivo upregulation of 1,25(OH)2 vitamin D3 receptor in human monocytes

Summary Mammalian cells increase net expression of 1,25(OH)₂D₃ receptors after exposure to physiological concentrations of 1,25(OH)₂D₃ in vitro. we examined specific binding of 1,25(OH)₂D₃ by human monocytes before and after daily administration of 1.5–2 ug 1,25(OH)₂D₃ p.o. for 3 days in 5 healthy normal D-replete probands. Median specific binding (N_max) at baseline was 793 molecules/cell and 2052 or 2828 at 24h and 72h of 1,25(OH)₂D₃ treatment respectively. The results suggest (a) up-regulation of 1,25(OH)₂D₃ receptors occurs in man and (b) monocyte preparations can be used to assess receptor regulationin vivo.