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891.
Yamamoto N Yang M Jiang P Xu M Tsuchiya H Tomita K Moossa AR Hoffman RM 《Clinical & experimental metastasis》2003,20(7):633-638
We have established stable, bright green fluorescent protein (GFP)- or red fluorescent protein (RFP)-expressing HT-1080 human
fibrosarcoma clones. These cell lines showed similar cell proliferation rates and high-frequency experimental lung metastasis.
The HT-1080-GFP and -RFP clones enable simultaneous real-time dual-color imaging in the live animal. HT-1080 cells were transduced
with retroviral vectors containing GFP or RFP and the neomycin resistance gene. Stable transformants were selected stepwise
with G418 up to 800 μl/ml. Subsequently, high GFP- or RFP-expressing clones, HT-1080-GFP or HT-1080-RFP, respectively, were
selected. 3×106 cells from each clone were mixed and injected into the tail vein of SCID mice. The cells seeded the lung at high frequency
with subsequent formation of pure green and pure red colonies as well as mixed yellow colonies with different patterns visualized
directly on excised lungs. The lung metastases were also visualized by external fluorescence imaging in live animals through
skin-flap windows over the chest wall. Lung metastases were observed on the lung surface of all mice. SCID mice well tolerated
multiple surgical procedures for direct-view imaging via skin-flap windows. Real-time metastatic growth of the two different
colored clones in the same lung was externally imaged with resolution and quantification of green, red, or yellow colonies
in live animals. The color coding enabled determination of whether the colonies grew clonally or were seeded as a mixture
with one cell type eventually dominating, or whether the colonies grew as a mixture. The simultaneous real-time dual-color
imaging of metastatic colonies described in this report gives rise to the possibility of color-coded imaging of clones of
cancer cells carrying various forms of gene of interest.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
892.
Ana L Sanchez Carrie M Langdon Mahmood Akhtar Jun Lu Carl D Richards Premysl Bercik Derek M McKay 《Journal of interferon & cytokine research》2003,23(4):193-201
The use of biologics has promising potential in the treatment of inflammation. Studies with cultured cells and mouse models of disease have ascribed proinflammatory and anti-inflammatory functions to oncostatin M (OSM) and the related cytokine, interleukin-6 (IL-6). Here, we examined the effect of systemic administration of adenoviral (Ad) vectors encoding either murine OSM (AdMuOSM) or murine IL-6 (AdMuIL-6) in a mouse model of colitis. BALB/c mice were treated with a 5-day course of 4% dextran-sodium sulfate (DSS) water with or without administration of adenoviral vectors (i.p. or i.m. at 10(7) plaque-forming units [pfu]) given as a cotreatment or therapy. The deletion variant of the adenovirus served as a control for adenoviral infection. Colitis was assessed by (1) morphology (damage score, macrophage infiltration, apoptosis) and (2) function (myeloperoxidase activity and Ussing chamber analysis of epithelial ion transport). Infection with adenovirus alone did not affect colonic form or function. AdMuOSM (either i.p. or i.m.) significantly reduced the severity of the DSS-induced colitis. There was less damage, reduced macrophage infiltration, fewer apoptotic bodies, and a significant improvement in stimulated ion transport in colonic tissues from the treated mice. No benefit of AdMuIL-6 treatment was observed in this model system. Thus, systemic administration of AdMuOSM given as a cotreatment and to a lesser extent as a therapy was found to be of benefit in DSS-induced colitis, a murine model of inflammatory bowel disease (IBD). 相似文献
893.
Morphological and functional plasticity of olfactory ensheathing cells 总被引:12,自引:0,他引:12
In the primary olfactory pathway, olfactory ensheathing cells (OECs) extend processes to envelop bundles of olfactory axons
as they course towards their termination in the olfactory bulb. The expression of growth-promoting adhesion and extracellular
matrix molecules by OECs, and their spatially close association with olfactory axons are consistent with OECs being involved
in promoting and guiding olfactory axon growth. Because of this, OECs have been employed as a possible tool for inducing axonal
regeneration in the injured adult CNS, resulting in significant functional recovery in some animal models and promising outcomes
from early clinical applications. However, fundamental aspects of OEC biology remain unclear. This brief review discusses
some of the experimental data that have resulted in conflicting views with regard to the identity of OECs. We present here
recent findings which support the notion of OECs as a single but malleable phenotype which demonstrate extensive morphological
and functional plasticity depending on the environmental stimuli. The review includes a discussion of the normal functional
role of OECs in the developing primary olfactory pathway as well as their interaction with regenerating axons and reactive
astrocytes in the novel environment of the injured CNS. The use of OECs to induce repair in the injured nervous system reflects
the functional plasticity of these cells. Finally, we will explore the possibility that recent microarray data could point
to OECs assuming an innate immune function or playing a role in modulating neuroinflammation. 相似文献
894.
海洛因成瘾复吸大鼠脑组织超微结构和部分神经递质的变化 总被引:5,自引:0,他引:5
目的:建立海洛因成瘾、脱毒,复成瘾、脱毒,再成瘾、脱毒3个阶段大白鼠模型,了解海洛因致各阶段大白鼠脑损害的动态趋势。方法:电镜下观察脑超微结构变化,荧光分光度法测定脑NA、DA、5-HT等神经递质的含量。结果:3个阶段大鼠脑内多部位神经元胞体、轴突、树突都出现变性、凋亡、胀亡等超微病理结构改变,神经胶质细胞、神经毯也出现相应的超微病理结构改变,而且随复吸次数增多而病变加重。脑NA、DA、5-HT、含量升高,而且随复吸次数增多而升高。结论:大白鼠脑组织出现广泛性超微病理结构改变,随复吸次数增多而病变加重,脑神经递质含量也随复吸次数增多而升高。 相似文献
895.
Kenichi Ohashi Yo Kato Jun Kanno Tsutomu Kasuga 《Virchows Archiv : an international journal of pathology》1990,417(2):137-143
Summary Normal oesophagus specimens taken from 65 autopsy cases and surgical specimens from 127 oesophageal carcinoma cases were examined
histopathologically to determine melanocyte incidence and distribution. Melanocytes were found in the epithelio-stromal junction
in 7.7% of normal oesophagus specimens examined at autopsy, and in 29.9% of surgical cases with oesophageal carcinoma. Positive
specimens in the latter groups, especially from pre-operatively irradiated individuals, showed a more remarkable increase
of melanocytes than was evident in any of the normal oesophageal samples. There were no significant differences in incidence
between males and females, or between age groups. In cases where the cancer invaded into deeper stroma, the melanocytes were
mainly observed in the normal epithelium around the carcinomas. Epithelial and stromal elements of the melanotic mucosa commonly
showed hyperplastic changes such as acanthosis or basal cell hyperplasia, and chronic oesophagitis. Melanocytes were observed
most commonly in the lower part of the oesophagus, the site where malignant melanoma of the oesophagus, most often originates.
These results strongly suggest that the melanocyte increase observed in areas of hyperplastic epithelium and chronic oesophagitis
may play an important role as a precursor lesion for malignant melanoma in the oesophagus. 相似文献
896.
研究了磺化聚醚砜吸附柱对血浆中亚甲蓝的吸附效果,并检测了流经吸附柱的牛血清白蛋白随时间变化的规律以及过柱前后血浆中主要生化指标的变化情况.结果:磺化聚醚砜对亚甲蓝的吸附效果明显优于聚醚砜对亚甲蓝的吸附效果;其对白蛋白的吸附较小;对血浆中主要生化指标的影响可以忽略不计. 相似文献
897.
Kushiro K Zakir M Sato H Ono S Ogawa Y Meng H Zhang X Uchino Y 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,131(4):406-415
Saccular and utricular organs are essential for postural stability and gaze control. Although saccular and utricular inputs are known to terminate on vestibular neurons, few previous studies have precisely elucidated the origin of these inputs. We investigated the saccular and utricular inputs to single vestibular neurons in whole vestibular nuclei of decerebrated cats. Postsynaptic potentials were recorded from vestibular neurons after electrical stimulation of the saccular and utricular nerves. Ascending and descending axonal projections were examined by stimulating the oculomotor/trochlear nuclei and the cervical segment of the spinal cord, respectively. After each experiment, locations of recorded neurons were identified. The recorded neurons (140) were classified into vestibulo-spinal (79), vestibulo-oculo-spinal (9), and vestibulo-ocular (3) neurons based on antidromic responses; 49 other vestibular neurons were unidentified. The majority of recorded neurons were mainly located in the lateral vestibular nucleus. Most of the otolith-activated vestibular nuclei neurons seemed to participate in vestibulospinal reflexes. Of the total 140 neurons recorded, approximately one third (51) received saccular and utricular inputs (convergent neurons). The properties of these 51 convergent neurons were further investigated. Most (33/51) received excitatory postsynaptic potentials (EPSPs) after saccular and utricular nerve stimulation. These results implied that most of the convergent neurons in this study additively coded mixed information for vertical and horizontal linear acceleration. Based on the latencies of convergent neurons, we found that an early integration process for vertical and horizontal linear acceleration existed at the second-order level. 相似文献
898.
Frints SG Jun L Fryns JP Devriendt K Teulingkx R Van den Berghe L De Vos B Borghgraef M Chelly J Des Portes V Van Bokhoven H Hamel B Ropers HH Kalscheuer V Raynaud M Moraine C Marynen P Froyen G 《American journal of medical genetics. Part A》2003,(3):367-374
We describe a 59-year-old male (patient A059) with moderate to severe mental retardation (MR) and a pericentric inversion of the X-chromosome: inv(X)(p21.1;q22.1). He had short stature, pectus excavatum, general muscle wasting, and facial dysmorphism. Until now, no other patients with similar clinical features have been described in the literature. Molecular analysis of both breakpoints led to the identification of a novel "Nuclear RNA export factor" (NXF) gene cluster on Xq22.1. Within this cluster, the NXF5 gene was interrupted with subsequent loss of gene expression. Hence, mutation analysis of the NXF5 and its neighboring homologue, the NXF2 gene was performed in 45 men with various forms of syndromic X-linked MR (XLMR) and in 70 patients with nonspecific XLMR. In the NXF5 gene four nucleotide changes: one intronic, two silent, and one missense (K23E), were identified. In the NXF2 gene two changes (one intronic and one silent) were found. Although none of these changes were causative mutations, we propose that NXF5 is a good candidate gene for this syndromic form of XLMR, given the suspected role of NXF proteins is within mRNA export/transport in neurons. Therefore, mutation screening of the NXF gene family in phenotypically identical patients is recommended. 相似文献
899.
Kimura K Nakano T Park YB Tani M Tsuda H Beppu Y Moriya H Yokota J 《Clinical & experimental metastasis》2002,19(6):477-486
Relevant animal models for metastasis of osteosarcoma is needed to understand the biology and to develop the treatment modality
of metastasis of human osteosarcoma. Therefore, we screened six human osteosarcoma cell lines for metastatic ability in nude
mice. The HuO9 cell line was identified as being metastatic to the lung after intravenous injection. We established two sublines,
HuO9-M112 and HuO9-M132, with high metastatic potential to the lung from the parental HuO9 cells by in vivo selection. There were no differences between these two sublines and the parental cells in the growth rate in vitro and the tumorigenicity after subcutaneous injection in nude mice, however, mice injected with the metastatic sublines became
moribund earlier than mice injected with the parental HuO9 cells did. Thus, adriamycin (ADR) and recombinant interleukin-12
(IL-12) were administered to mice injected with the HuO9-M112 subline to suppress experimental lung metastases. Production
of lung colonies was significantly suppressed and the prognoses of mice were significantly improved by both ADR and IL-12
treatments. These results indicate that both ADR and IL-12 are effective agents against pulmonary metastatic osteosarcoma,
and that these sublines are useful for studies on the biological behavior and treatment of pulmonary metastatic osteosarcoma.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
900.