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941.
The naturally-occurring compound, n-butylidenephthalide (BP), which is isolated from the chloroform extract of Angelica sinensis (AS-C), has been investigated with respect to the treatment of angina. In this study, we have examined the anti-tumor effects of n-butylidenephthalide on glioblastoma multiforme (GBM) brain tumors both in vitro and in vivo. In vitro, GBM cells were treated with BP, and the effects of proliferation, cell cycle and apoptosis were determined. In vivo, DBTRG-05MG, the human GBM tumor, and RG2, the rat GBM tumor, were injected subcutaneously or intracerebrally with BP. The effects on tumor growth were determined by tumor volumes, magnetic resonance imaging and survival rate. Here, we report on the potency of BP in suppressing growth of malignant brain tumor cells without simultaneous fibroblast cytotocixity. BP up-regulated the expression of Cyclin Kinase Inhibitor (CKI), including p21 and p27, to decrease phosphorylation of Rb proteins, and down-regulated the cell-cycle regulators, resulting in cell arrest at the G(0)/G(1) phase for DBTRG-05MG and RG2 cells, respectively. The apoptosis-associated proteins were dramatically increased and activated by BP in DBTRG-05MG cells and RG2 cells, but RG2 cells did not express p53 protein. In vitro results showed that BP triggered both p53-dependent and independent pathways for apoptosis. In vivo, BP not only suppressed growth of subcutaneous rat and human brain tumors but also, reduced the volume of GBM tumors in situ, significantly prolonging survival rate. These in vitro and in vivo anti-cancer effects indicate that BP could serve as a new anti-brain tumor drug.  相似文献   
942.
An ideal expression algorithm should be able to tell truly different expression levels with small false positive errors and be robust to assay changes. We propose two algorithms. PQN is the non-central trimmed mean of perfect match intensities with quantile normalization. DQN is the non-central trimmed mean of differences between perfect match and mismatch intensities with quantile normalization. The quantiles for normalization can be either empirical or theoretical. When array types and/or assay change in a study, the normalization to common quantiles at the probe set level is essential. We compared DQN, PQN, RMA, GCRMA, DCHIP, PLIER and MAS5 for the Affymetrix Latin square data and our data of two sets of experiments using the same bone marrow but different types of microarrays and different assay. We found the computation for AUC of ROC at affycomp.biostat.jhsph.edu can be improved.  相似文献   
943.
Tsai YM  Chou SW  Lin YC  Hou CW  Hung KC  Kung HW  Lin TW  Chen SM  Lin CY  Kuo CH 《Life sciences》2006,79(13):1281-1286
Serum dehydroepiandrosterone sulfate (DHEA-S) concentration is known to be associated with the whole-body insulin sensitivity. The main purpose of the study was to investigate the effect of resistance exercise on DHEA-S concentration during a 72 h post-exercise recovery, and its relation to glucose tolerance and insulin sensitivity. Morning fasted serum samples was obtained from 19 male volunteers (aged 21.1+/-0.4 years) 24 h before the onset of exercise and 24 h, 48 h, and 72 h following exercise for measurements of DHEA-S, cortisol, and TNF-alpha. Oral glucose tolerance test (OGTT) and insulin response were determined 24 h before and 48 h after exercise. We found that resistance exercise causes a delayed suppression in serum DHEA-S levels during recovery (48 h and 72 h). This exercise challenge did not affect glucose tolerance, but insulin response during OGTT was significantly elevated. The increased insulin level was not associated with serum levels of cortisol and TNF-alpha. In conclusion, the present study found that resistance exercise has a DHEA-S lowering effect that persisted for 72 h. This change could be related to the elevated insulin concentrations during OGTT.  相似文献   
944.
Shyu KG  Lin S  Lee CC  Chen E  Lin LC  Wang BW  Tsai SC 《Life sciences》2006,78(19):2234-2243
Evodiamine, the major bioactive compound isolated from Chinese herbal drug named Wu-Chu-Yu, has been reported to exhibit anti-tumor growth and metastasis. However, the effect of evodiamine on angiogenesis remains to be investigated. We used the fresh medium containing evodiamine or human lung adenocarcinoma cell (CL1 cells) derived conditioned media free of evodiamine to test their capability to induce in vitro angiogenesis, i.e., human umbilical vein endothelial cells (HUVECs) tube formation and invasion. We demonstrated that evodiamine could directly inhibit in vitro HUVECs tube formation and invasion. Locally administered evodiamine also inhibited the in vivo angiogenesis in the chick embryo chorioallantoic membrane (CAM) assay. The gene expression of vascular endothelial growth factor (VEGF) and the p44/p42 mitogen-activated protein kinase (MAPK, ERK) that correlated with endothelial cells angiogenesis were inhibited by evodiamine. We found that the evodiamine-treated CL1 cells derived conditioned medium showed decreased VEGF release and reduced ability of inducing in vitro tube formation. After the collection of conditioned media, the VEGF expression of remaining CL1 cells were determined by Western analyses and revealed that evodiamine decreased VEGF expression. Moreover, administration of recombinant human VEGF(165) (rhVEGF(165)) induced tube formation and ERK phosphorylation by HUVECs, and partially attenuated inhibitory effect of evodiamine. From these results, we suggested that evodiamine is a potent inhibitor of angiogenesis. The mechanism might involve at least the inhibition of VEGF expression, probably through repression of ERK phosphorylation.  相似文献   
945.
Tsai SK  Lin MJ  Liao PH  Yang CY  Lin SM  Liu SM  Lin RH  Chih CL  Huang SS 《Life sciences》2006,78(23):2758-2762
The effects of caffeic acid phenethyl ester (CAPE), an antioxidant derived from propolis, on the infarct volume elicited by focal cerebral ischemia were studied on Long-Evans rats. Cerebral infarction was induced by microsurgical procedures with ligation of the right middle cerebral artery (MCA) and clipping of bilateral common carotid arteries (CCA) for 60 min. The rats were sacrificed 24 h later and serial brain slices of 2 mm thickness were taken and stained for the measurement of infarct area. CAPE was administered intravenously 15 min before MCA occlusion. Pretreatment of CAPE (0.1, 1 and 10 microg/kg) significantly reduced the total infarct volume from 169.6 +/- 14.5 mm3 (control) to 61.0 +/- 24.1 mm3 (0.1 microg/kg CAPE), 47.4 +/- 9.1 mm3 (1 microg/kg CAPE), and 42.4 +/- 8.7 mm3 (10 microg/kg CAPE), respectively. Plasma nitric oxide (NO) content was significantly increased in rats subjected to focal cerebral ischemia. It is concluded that CAPE possesses neuroprotective properties in focal cerebral ischemia injury in rats possibly through its antioxidant effect and/or via the upregulation of NO production.  相似文献   
946.
Neuronal migration is, along with axon guidance, one of the fundamental mechanisms underlying the wiring of the brain. As other organs, the nervous system has acquired the ability to grow both in size and complexity by using migration as a strategy to position cell types from different origins into specific coordinates, allowing for the generation of brain circuitries. Guidance of migrating neurons shares many features with axon guidance, from the use of substrates to the specific cues regulating chemotaxis. There are, however, important differences in the cell biology of these two processes. The most evident case is nucleokinesis, which is an essential component of migration that needs to be integrated within the guidance of the cell. Perhaps more surprisingly, the cellular mechanisms underlying the response of the leading process of migrating cells to guidance cues might be different to those involved in growth cone steering, at least for some neuronal populations.The migration of newly born neurons is a precisely regulated process that is critical for the development of brain architecture. Neurons arise from the proliferative epithelium that covers the ventricular space throughout the neural tube, an area named the ventricular zone (VZ). From there, newly born neurons adopt two main strategies to disperse throughout the central nervous system (CNS), designated as radial and tangential migration (Hatten 1999; Marín and Rubenstein 2003). During radial migration, neurons follow a trajectory that is perpendicular to the ventricular surface, moving alongside radial glial fibers expanding the thickness of the neural tube. In contrast, tangentially migrating neurons move in trajectories that are parallel to the ventricular surface and orthogonal to the radial glia palisade (Fig. 1). Besides their relative orientation, some of the basic mechanisms underlying the movement of cells using each of these two modes of migration are also different. For example, radially migrating neurons often use radial glial fibers as substrate, whereas tangentially migrating neurons do not seem to require their support to migrate. Even so, neurons may alternate from radial to tangential movement and vice versa during the course of their migration. This suggests that both types of migrations share common principles, in particular those directly related to the cell biology of movement (Marín et al. 2006).Open in a separate windowFigure 1.Representative migrations in the developing CNS. Multiple migrations coexist during embryonic development at different areas of the central nervous system. This schema summarizes some of these migrations during the second week of the embryonic period in the mouse. Neurons use tangential and radial migration to reach their final destination; both strategies are used by the same neurons at different stages of development (i.e., cortical interneurons in the forebrain and precerebellar neurons in the hindbrain). (IML) intermediolateral region of the spinal cord; (IO) inferior olive nucleus; (LGE) lateral ganglionic eminence; (LRN) lateral reticular nucleus; (MGE) medial ganglionic eminence; (NCx) neocortex; (OB) olfactory bulb.One of the structures that better illustrates how both types of migrations are integrated during brain development is the cerebral cortex, and so we will primarily refer to studies performed on cortical neurons for this review. The adult cerebral cortex contains two main classes of neurons: glutamatergic cortical projection neurons (also known as pyramidal cells) and GABAergic interneurons. Pyramidal cells are generated in the ventricular zone (VZ) of the embryonic pallium—the roof of the telencephalon—and reach their final position by radial migration (Rakic 2007). In contrast, cortical interneurons are born in the subpallium—the base of telencephalon—and reach the cerebral cortex through a long tangential migration (Corbin et al. 2001; Marín and Rubenstein 2001).The earliest cortical neurons form a transient structure known as the preplate, around embryonic day 10 (E10) of gestation age in the mouse. This primordial layer consists of Cajal-Retzius cells and the first cohort of pyramidal neurons, which will eventually populate the subplate. Cajal-Retzius cells, which play important roles during neuronal migration, arise from discrete pallial sources and colonize the entire surface of the cortex through tangential migration (Bielle et al. 2005; Takiguchi-Hayashi et al. 2004; Yoshida et al. 2006). The next cohort of pyramidal cells forms the cortical plate (CP) by intercalating in the preplate and splitting this primitive structure in a superficial layer, the marginal zone (MZ or layer I), and a deep layer, the subplate. The development of the neocortex progresses with new waves of neurons that occupy progressively more superficial positions within the CP (Gupta et al. 2002; Marín and Rubenstein 2003). Birth dating studies have shown that layers II–VI of the cerebral cortex are generated in an “inside-out” sequence. Neurons generated earlier reside in deeper layers, whereas later-born neurons migrate past existing layers to form superficial layers (Angevine and Sidman 1961; Rakic 1974). In parallel to this process, GABAergic interneurons migrate to the cortex, where they disperse tangentially via highly stereotyped routes in the MZ, SP, and lower intermediate zone/subventricular zone (IZ/SVZ) (Lavdas et al. 1999). Interneurons then switch from tangential to radial migration to adopt their final laminar position in the cerebral cortex (Ang et al. 2003; Polleux et al. 2002; Tanaka et al. 2003).  相似文献   
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950.
The number of somatic kineties in Pelagostrobilidium ranges from 4 to 6 according to the present state of knowledge. This study investigates Pelagostrobilidium liui n. sp. using live observation, protargol stain, and small subunit rDNA data sequencing. Pelagostrobilidium liui n. sp. is characterized by having a spherical‐shaped body, four somatic kineties, with kinety 2 spiraled around the left side of body, about six elongated external membranelles, and invariably no buccal membranelle. It differs from its most similar congener, Pelagostrobilidium minutum Liu et al., 2012 , in (i) cell shape; (ii) macronucleus width; (iii) oral apparatus; (iv) anterior orientation of kinety 2; (v) location where kinety 2 commences; (vi) arrangement of kinety 1; (vii) distance between the anterior cell end and the locations where kineties commence; and (viii) the presence of 12 different bases (including two deletions) in the small subunit rDNA sequences. The diagnosis of P. minutum Liu et al., 2012 is also improved to include the following new characteristics: invariably four somatic kineties; kineties 2 and 4 alone commence at the same level; kinety 2 originates from right anterior cell half on ventral side, extends sinistrally posteriorly, over kinety 1, around left posterior region, terminates near posterior cell end on dorsal side; kinety 1 commences below anterior third of kinety 2.  相似文献   
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