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61.
Effective high-capacity gutless adenoviral vectors mediate transgene expression in human glioma cells. 总被引:2,自引:0,他引:2
Marianela Candolfi James F Curtin Wei-Dong Xiong Kurt M Kroeger Chunyan Liu Altan Rentsendorj Hasmik Agadjanian Lali Medina-Kauwe Donna Palmer Philip Ng Pedro R Lowenstein Maria G Castro 《Molecular therapy》2006,14(3):371-381
Glioblastoma multiforme (GBM) is the most common subtype of primary malignant brain tumor. Although serotype 5 adenoviral vectors (Ads) have been used successfully in clinical trials for GBM, the capacity of Ads to infect human glioma cells and the expression of adenoviral receptors in GBM cells have been challenged. In this report, we studied the expression of three molecules that have been shown to mediate adenoviral entry into cells, i.e., coxsackie and adenovirus receptor (CAR), integrin alphavbeta3 (INT), and major histocompatibility complex class I (MHCI), in rodent glioma cell lines and low-passage primary cultures and cell lines from human GBM. We correlated levels of expression of CAR, INT, and MHCI with transduction efficiency elicited by several high-capacity helper-dependent adenoviral vectors (HC-Ads). Expression levels of adenoviral receptors were variable among the different GBM cells studied. HC-Ad-mediated therapeutic gene expression was efficient, ranging between 20 and 80% of the total target cells expressing the encoded transgenes. Our results show no correlation between the levels of CAR, INT, or MHCI molecules and the levels of transgene expression or the number of GBM cells transduced. We conclude that expression levels of adenoviral receptors do not predict their transduction efficiency or biological function. 相似文献
62.
Diaphragmaticmuscleisanimportantrespiratorymuscle,anddiaphragmaticfatiguecanleadtomanydisorders .Onlyintherecent 2 0 yearshavethesys temicresearchesbeen performedtoinvestigatethefunctionofdiaphragmanditspathophysiology .Di aphragmaticfatiguecanbeinducedby… 相似文献
63.
目的:探讨非小细胞肺癌患者治疗前血清肿瘤标志物水平与肿瘤骨转移之间的相关性。材料和方法:受检患者58名治疗前均行血清Cy21-1、SCC、NSE、CEA和CA15-3测定和SPECT全身骨显像。结果:血清Cy21-1和CA15-3水平与全身骨显像结果相关。(P<0.05),血清SCC,NSE及CEA水平则无相关(P>0.05)。结论:血清中Cy21-1和CA15-3升高水平与肿瘤骨转移之间存在正相关关系,尤以Cy21-1为著。 相似文献
64.
采用原子吸收光谱法测定了30例糖尿病患者血清锌、镁、钙的含量,并与30例正常人相比较。结果表明,其锌和镁较正常人为低(P<0.05),但钙与正常人无显著性差别。另外,本文还对锌、镁与糖尿病的关系进行了探讨。 相似文献
65.
Five compounds have been isolated from the stems and leaves of Isodon albopilosus. On the basis of spectroscopic and chemical data, they were identified as macrocalyxin C, stearic acid, beta-sitosterol, ursolic acid and beta-sitosterol-beta-D-glucoside, respectively. 相似文献
66.
OBJECTIVE: To observe the morphological changes of Balb/C mouse embryonic stem cells following directed differentiation into pancreatic islet-like cell clusters (PICC) in vitro using atomic force microscope (AFM). METHODS: Balb/C mouse embryonic stem cells were first cultured into embryonic bodies (EBs) and allowed to differentiate spontaneously for 4 days. The cells were then transferred to gelatin-coated dishes for the EBs to attach and spread on the tissue culture plates, in the course of which a series of cell growth factors such as basic fibroblast growth factor (bFGF), insulin-like growth factor 1 (IGF-1) and nicotinamide were added into the culture medium at specific time points to induce directed differentiation of the stem cells into PICC. Immunocytochemistry was employed to detect the cells positive for insulin and glucagon, which were observed with AFM. RESULTS: The embryonic stem cells developed into cell clusters of different sizes, in which the cells were tightly arranged. Islet B cells were numerous in the center of clusters and darkly stained, but fewer in the peripherals with lighter stains. Islet A cells expressing glucagon were relatively fewer in the cell clusters, found mainly in the peripherals. Scanning of the insulin-positive clusters by AFM revealed large quantity of tissue fibers resembling nerve fibers that formed a reticular structure in disorderly arrangement. Numerous round granules were observed in the cytoplasm of almost identical sizes ranging from 0.5 to 1.0 mum in diameter. CONCLUSION: The cell clusters obtained by directed differentiation are mature in both morphology and function with also well organized structures. 相似文献
67.
目的:探讨3D—DSA在颅内动脉瘤诊断和治疗中的应用价值。方法:对蛛网膜下腔出血患者常规行DSA检查,发现病变或可疑病变后行3D—DSA检查。结果:26例颅内动脉瘤中检出动脉瘤31枚,其中后交通9枚,C1段3枚,C2段5枚,C3段3枚,前交通6枚,大脑中3枚。椎动脉动2枚。3例2D—DSA未见病变3D—DSA确诊,5例因血管重叠3D—DSA排除了动脉瘤。6枚GDC栓塞,5枚手术夹闭,2枚颈内动脉可脱性球囊封阻术。结论:3D—DSA极大提高了脑血管造影检查的准确性和可靠性,为动脉瘤的介入治疗和手术夹闭提供了可靠保障,在临床诊疗中具有很高的应用价值。 相似文献
68.
目的探讨膀胱出口梗阻(BOO)后逼尿肌收缩蛋白表达和膀胱重量的改变及意义。方法BOO组病人16例,筛选条件为入院诊断良性前列腺增生症(BPH)并经尿动力学压力-流率检查证实为高压低流型;对照组5例,为外伤等情况入院并排除有下尿路梗阻病史者。BOO组所有病例均行耻骨上经膀胱前列腺摘除术,术前B超检查测定膀胱重量和前列腺内外径比值,术中切取膀胱上壁组织2cm×1cm×1cm大小,标本行RT-PCR反应,检测膀胱逼尿肌中肌动蛋白和肌球蛋白mRNA的表达,并比较其与膀胱重量间的线性相关性。结果BOO组与对照组膀胱重量分别为(92.15±34.89)g和(56.08±20.35)g,(P<0.05);前列腺内外径比值分别为(0.57±0.16)和(0.18±0.06),(P<0.01);与对照组相比,BOO组肌动蛋白和肌球蛋白mRNA的表达量均有显著增加,分别为(40.32±59.67)×106和(6.59±5.62)×106,(P值均<0.01);且两者表达量与膀胱重量之间均有明显线性正相关性(P<0.05)。结论逼尿肌中肌动蛋白和肌球蛋白的表达与膀胱逼尿肌的功能状态密切相关。 相似文献
69.
肝尾状叶由于解剖位置特殊,位置深,难以显露,手术难度大,是肝脏外科领域手术操作的难点与研究热点.随着肝血流控制技术的发展、肝实质离断技术的提高,肝尾状叶肿瘤切除率明显提高[1].2006年4月至2008年10月,我科完成单独肝尾状叶血管瘤切除术9例,现将手术技巧与疗效报道如下. 相似文献
70.
This review summarized some articles on the effect of the septal area in acupuncture analgesia. The data showed that the pain threshold of animal was increased when septal area was stimulated by electro-acupuncture, and that electrical stimulation of septal area had a marked inhibitory effect on the pain discharges of cells in parafascicular nucleus of thalamus, lateral habenular nucleus, periaqueductal gray and dorsal raphe nucleus. The septal area play an important role in acupuncture analgesia. The majority of the cholinergic neurons in septal area are located in nucleus of the vertical limb of the diagonal band (VDB); gamma-aminobutyric acid of septal area is mainly found in the diagonal band nucleus(td); Dopamine is present in high levels in td and lateral septal nucleus(S1) of septal area; The S1 contain high densities enkephalin-containing neuronal cell bodies and terminals; In addition, substance P and norepinephrine are also high levels in the septal area. These substance above-mentioned have a relations with acupuncture analgesia of septal area. A large number of serotonin-containing neurons are found in the raphe nuclei. The serotonin play an important role in acupuncture analgesia. The serotonin-containing neurons in dorsal raphe nucleus project to S1. The fiber connections of the raphe nuclei with the td are reciprocation. The periaqueductal gray is a important structure on pain modulation. It projects to septal area and receives the fibers from S1. A number of adrenergic neurons are located within the locus coeruleus. The locus coeruleus participate pain modulation and acupuncture analgesia. The neuro-anatomy study demonstrated that locus coeruleus projects to septal area.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献