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381.
体外纯化培养的成熟星形胶质细胞经冷冻复苏方法处理后,诱导转化为放射状胶质细胞的类似细胞(RGLCs细胞).星形胶质细胞的诱导转化率与其冷冻过程的温度、时间有关.冷冻保护液中的DMSO对星形胶质细胞的诱导转化过程无关.这些结果显示冷冻复苏方法诱导星形胶质细胞的转化是由物理刺激诱导的. 相似文献
382.
383.
DMM在pH<2.5时会发生水解,本文主要研究了DMM在酸性介质中的循环伏安行为随时间的变化情况,并用电化学方法验证了DMM的水解产物是甲醛和甲醇. 相似文献
384.
我们使用Leustroducsin、毕西巴尼(OK—432)及Z—100三种细菌制剂作为诱导剂,通过培养人骨髓基质细胞株BM01,观察此三种物质对BM01白细胞介素6(IL_6)产生的影响,用ELISA法检测培养液中IL_6的含量。结果显示,三种诱导剂均可使BMO1分泌ILL_6增多,以Leustrodcsin的诱导作用最显著。 相似文献
385.
Isolation of human epidermal stem cells by adherence and the reconstruction of skin equivalents 总被引:47,自引:0,他引:47
Kim DS Cho HJ Choi HR Kwon SB Park KC 《Cellular and molecular life sciences : CMLS》2004,61(21):2774-2781
The isolation of human epidermal stem cells is critical for their clinical applications. In the present study, we isolated three populations of epidermal keratinocytes according to their ability to adhere to collagen type IV: i.e., rapidly adhering (RA), slowly adhering (SA), and non-adhering (NA) cells. The aim of this study was to characterize RA cells and to investigate the possibility of using these cells for epidermis reconstruction. To identify RA cells, flow cytometric analysis was performed using anti-6 integrin and anti-CD71 antibodies. RA cells express high levels of 6 integrin and low levels of CD71, which are considered as markers of an epidermal stem cell nature. Furthermore, electron microscopy showed that RA cells are small and have a high nuclear to cytoplasmic ratio, whereas SA and NA cells have well-developed cellular organelles and abundant tonofilaments. Western blot analysis showed that RA cells are slow cycling and express p63, a putative epidermal stem cell marker, whereas SA and NA cells express c-Myc, which is known to regulate stem cell fate. To compare epidermal regenerative abilities, skin equivalents (SEs) were made using RA, SA, and NA cells. The epidermis constructed from RA cells was well formed compared to those formed from SA or NA cells. In addition, only SEs with RA cells expressed 6 integrin and 1 integrin at the basal layer. These results indicate that RA cells represent epidermal stem cells and are predominately comprised of stem cells. Therefore, the isolation of RA cells using a simple technique offers a potential route to their clinical application, because they are easily isolated and provide a high yield of epidermal stem cells.Received 2 July 2004; received after revision 20 August 2004; accepted 10 September 2004 相似文献
386.
Cecchi C Liguri G Fiorillo C Bogani F Gambassi M Giannoni E Cirri P Baglioni S Ramponi G 《Cellular and molecular life sciences : CMLS》2004,61(14):1775-1784
An acylphosphatase (AcPase) overexpression study was carried out on SH-SY5Y neuroblastoma cells, using a
green fluorescent fusion protein (AcP-GFP), with GFP acting as a reporter protein. The cellular proliferation rate
was significantly reduced by overexpression of AcPase by a factor of ten. In contrast, clones transfected with two
inactive AcPase mutants showed a growth rate comparable to control cells. This suggests that AcPase catalyzes the
proliferative down-regulation. AcPase-overexpressing clones showed a physiological mortality rate as assessed by an
MTT reduction test and by evaluation of necrotic markers. DNA fragmentation analysis and assays of caspase-3 and
poly (ADP-ribose) polymerase (PARP)-active fragments showed no evidence of any apoptotic pattern. AcPase
overexpression led to a marked increase in PARP activity as well as Bcl-2 content; these are commonly up-regulated
during differentiative processes in neuronal cells. In fact, the typical differentiation marker,
growth-associated-protein 43, was significantly up-regulated. Microscopic observations also showed a clear
increase in the differentiative phenotype in AcPase-overexpressing cells. Our results clearly show that AcPase
plays a primary causative role in neuronal differentiation.Received 3 May 2004; accepted 25 May 2004 相似文献
387.
HAb18G/CD147-mediated calcium mobilization and hepatoma metastasis require both C-terminal and N-terminal domains 总被引:4,自引:0,他引:4
Jiang JL Chan HC Zhou Q Yu MK Yao XY Lam SY Zhu H Ho LS Leung KM Chen ZN 《Cellular and molecular life sciences : CMLS》2004,61(16):2083-2091
HAb18G/CD147 is a heavily glycosylated protein containing two immunoglobulin superfamily domains. Our previous studies have indicated that overexpression of HAb18G/CD147 enhances metastatic potentials in human hepatoma cells by disrupting the regulation of store-operated Ca2+ entry by nitric oxide (NO)/cGMP. In the present study, we investigated the structure-function of HAb18G/CD147 by transfecting truncated HAb18G/CD147 fragments into human 7721 hepatoma cells. The inhibitory effect of HAb18G/CD147 on 8-bromo-cGMP-regulated thapsigargin-induced Ca2+ entry was reversed by the expression of either C or N terminus truncated HAb18G/CD147 in T7721C and T7721N cells, respectively. The potential effect of HAb18G/CD147 on metastatic potentials, both adhesion and invasion capacities, of hepatoma cells was abolished in T7721C cells, but not affected in T7721N cells. Release and activation of matrix metalloproteinases (MMPs), MMP-2 and MMP-9, were found to be enhanced by the expression of HAb18G/CD147, and this effect was abolished by both truncations. Thapsigargin significantly enhanced release and activation of MMPs (MMP-2 and MMP-9) in non-transfected 7721 cells, and this effect was negatively regulated by SNAP. However, no effects of thapsigargin or SNAP were observed in T7721 cells, and expression of HAb18G/CD147 enhanced secretion and activation of MMPs at a stable and high level. Taken together, these results suggest that both ectodomain and intracellular domains of HAb18G/CD147 are required to mediate the effect of HAb18G/CD147 on the secretion and activation of MMPs and metastasis-related processes in human hepatoma cells by disrupting the regulation of NO/cGMP-sensitive intracellular Ca2+ mobilization although each domain may play different roles.Received 1 April 2004; received after revision 15 June 2004; accepted 22 June 2004 相似文献
388.
The presence and functional role of the swelling-activated Cl- current (ICl(swell)) in rabbit cardiac Purkinje cells was examined using patch-clamp methodology. Extracellular hypotonicity (210 or 135 mOsm) activated an outwardly rectifying, time-independent current with a reversal potential close to the calculated Cl- equilibrium potential (ECl). The magnitude of this current was related to tonicity of the superfusate. The current was blocked by 0.5 mM 4,4-diisothiocyanostilbene-2,2-disulfonic acid (DIDS). These features are comparable to those of ICl(swell) found in sinoatrial nodal, atrial, and ventricular myocytes. ICl(swell) activation at 210 and 135 mOsm depolarized the resting membrane potential with 6 and 10 mV and shortened the action potential by 18 and 33%, respectively. DIDS partially reversed ICl(swell)-induced action potential changes. We conclude that ICl(swell) is present in Purkinje cells and its activation leads to action potential shortening and resting membrane potential depolarization, both of which can promote the development of reentrant arrhythmias.Received 20 January 2004; received after revision 17 February 2004; accepted 25 February 2004 相似文献
389.
390.
Polarization of immunity induced by direct injection of naked sequence-stabilized mRNA vaccines 总被引:2,自引:0,他引:2
Carralot JP Probst J Hoerr I Scheel B Teufel R Jung G Rammensee HG Pascolo S 《Cellular and molecular life sciences : CMLS》2004,61(18):2418-2424
In the context of developing a safe genetic vaccination strategy we tested and studied globin-stabilized mRNA-based
vaccination in mice. This vaccination strategy has the advantages of genetic vaccination (easy production, adaptability to
any disease and inexpensive storage when lyophilized), but not the drawbacks of DNA vaccination (long-term uncontrolled
expression of a transgene, possibility of integration into the host genome and possible induction of anti-DNA antibodies).
We report here that injection of naked -globin untranslated region (UTR)-stabilized mRNA coding for
-galactosidase is followed by detectable translation in vivo. In addition, we show that such a vaccination strategy
primes a T helper 2 (Th2) type of response which can be enhanced and shifted to a Th1-type immune response by application
of recombinant granulocyte/macrophage colony-stimulating factor 1 day after mRNA injection. Our data demonstrate that the
administration of globin UTR-stabilized mRNA is a versatile vaccination strategy that can be manipulated to fit the
requirement of antiviral, antibacterial or antitumor immunity.Received 14 June 2004; received after revision 19 July 2004; accepted 9 August 2004 相似文献