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81.
Abstract: The influence of culture conditions on the development of normal characteristics of the choroid plexus epithelium has been investigated in vitro with respect to polarity, barrier properties, transport, and secretory activity. Withdrawal of serum supplement in the culture medium of cells grown on filters caused morphologically visible changes by an increased trimming of microvilli at the apical membrane side, which is accompanied by an increased expression of the Na+,K+-ATPase. Moreover cells under serum-free conditions exhibit structural changes in tight junctional zonula occludens protein-1 (ZO-1) organization, a reduced permeability, and a drastically increased electrical resistance from 150 Ω· cm2 in the presence of serum to 1,500 Ω· cm2 after serum withdrawal. Under these conditions, cell monolayers are able to build up a transcellular proton gradient and to secrete fluid into the upper (apical) filter compartment, which is accompanied by a polarized secretion of proteins like transthyretin. Active transport of the dyes fluorescein and phenol red by the organic anion transporter is found to be driven by the Na+,K+-ATPase. We come to the conclusion that removal of serum favors the differentiation process of the plexus epithelium in vitro, which brings the cell culture model closer to the physiological situation in vivo. We present preliminary evidence that epidermal growth factor may be one component in serum preventing the proper in vitro differentiation.  相似文献   
82.
Multiple sclerosis (MS) is a chronic inflammatory disease affecting the central nervous system (CNS). Despite introducing multiple immunomodulatory approaches for MS, there are still major concerns about possible ways for improving remyelination in this disease. Microglia exert essential roles in regulation of myelination processes, and interaction between colony-stimulating factor 1 (CSF1) with its receptor CSF1R is considered as a key regulator of microglial differentiation and survival. The aim of this study was to investigate possible roles for a CSF1R inhibitor PLX3397 in recovery of central myelination processes. Chronic demyelination was induced in mice by addition of 0.2% cuprizone to the chow for 12 weeks. Next, animals were undergoing a diet containing 290 mg/kg PLX3397 to induce microglial ablation. The PLX3397 treatment caused a significant decrease in the rate of expression for the CSF1/CSF1R axis, and a reduction in the protein expressions for the microglial marker Iba-1 and for the oligodendrocyte marker Olig-2. Findings from Luxol fast blue (LFB) staining and transmission electron microscopy (TEM) showed an increase in the rate of myelination for the mice receiving PLX3397. The rate of destruction in the nerve fibers and the extent of the gaps formed between layers of myelin sheaths was also reduced after the treatment with PLX3397. In addition, animals experienced an improvement in recovery of motor deficit after receiving PLX3397 (for all P < 0.05). It could be concluded that PLX3397 could retain myelination in the MS model possibly through regulation of the myelin environment.  相似文献   
83.
CSF purines were grossly elevated compared with controls only in adenylosuccinate lyase (ADSL) deficiency and TB meningitis. The former representing low permeability, the latter severe damage to the normal blood/brain barrier. By contrast, the similarity to controls, with no difference between Lesch–Nyhan disease (LND) or LND variants, would exclude hypoxia as a factor in the severe neurological deficits in LND. Similar findings in purine nucleoside phosphorylase (PNP) deficiency (although nucleosides replace the normal bases) likewise exclude hypoxia in the aetiology of the albeit milder neurological deficits.  相似文献   
84.
目的:探究顺铂联合针灸疗法对晚期肺癌患者血清集落刺激因子(CSF)、肿瘤坏死因子(TNF-alpha)与白细胞介素2(IL2)水平的 影响。方法:选取我院肿瘤科收治的晚期肺癌患者60 例,并将其随机分为对照组和实验组。对照组30 例患者仅予顺铂常规治疗; 实验组30 例患者顺铂在常规治疗的基础上加用针刺肺俞、丰隆、中府、太渊、尺泽、心俞、天宗、膻中、膏肓、尺泽、背压痛点、灸丹 田穴位。治疗前后,检测和比较两组患者的血清CSF、TNF-alpha与IL2 水平。结果:治疗前,两组患者的血清CSF、TNF-alpha、IL2 水平比 较均无统计学差异(P>0.05);治疗后,两组的血清CSF、TNF-alpha、IL2水平均较治疗前降低,且实验组显著低于对照组,差异均有统计 学意义(P<0.05)。实验组的治疗总有效率明显高于对照组,脱发、失眠、白细胞减少的发生率均明显低于对照组,差异均具有统计 学意义(P<0.05)。结论:顺铂联合针灸治疗能够明显降低晚期肺癌患者的血清CSF、TNF-alpha与IL2 水平,进而可能提高患者的免疫 功能和临床疗效,值得临床进一步研究和推广应用。  相似文献   
85.
The choroid plexus (CP) epithelium develops from the ependyma that lines the ventricular system, and plays a critical role in the development and function of the brain. In addition to being the primary site of CSF production, the CP maintains the blood-CSF barrier via apical tight junctions between epithelial cells. Here we show that the 22-member γ-protocadherin (γ-Pcdh) family of cell adhesion molecules, which we have implicated previously in synaptogenesis and neuronal survival, is highly expressed by both CP epithelial and ependymal cells, in which γ-Pcdh protein localization is, surprisingly, tightly restricted to the apical membrane. Multi-label immunostaining demonstrates that γ-Pcdhs are excluded from tight junctions, basolateral adherens junctions, and apical cilia tufts. RT-PCR analysis indicates that, as a whole, the CP expresses most members of the Pcdh-γ gene family. Immunostaining using novel monoclonal antibodies specific for single γ-Pcdh proteins shows that individual epithelial cells differ in their apically localized γ-Pcdh repertoire. Restricted mutation of the Pcdh-γ locus in the choroid plexus and ependyma leads to significant reductions in ventricular volume, without obvious disruptions of epithelial apical-basal polarity. Together, these results suggest an unsuspected role for the γ-Pcdhs in CSF production and demonstrate a surprising molecular heterogeneity in the CP epithelium.  相似文献   
86.
Age, sex, and gonadal hormones have profound effects on ischemic stroke outcomes, although how these factors impact basic stroke pathophysiology remains unclear. There is a plethora of inconsistent data reported throughout the literature, primarily due to differences in the species examined, the timing and methods used to evaluate injury, the models used, and confusion regarding differences in stroke incidence as seen in clinical populations vs. effects on acute neuroprotection or neurorepair in experimental stroke models. Sex and gonadal hormone exposure have considerable independent impact on stroke outcome, but these factors also interact with each other, and the contribution of each differs throughout the lifespan. The contribution of sex and hormones to experimental stroke will be the focus of this review. Recent advances and our current understanding of age, sex, and hormone interactions in ischemic stroke with a focus on inflammation will be discussed.  相似文献   
87.
Effective control of the Ca2+ homeostasis in any living cell is paramount to coordinate some of the most essential physiological processes, including cell division, morphological differentiation, and intercellular communication. Therefore, effective homeostatic mechanisms have evolved to maintain the intracellular Ca2+ concentration at physiologically adequate levels, as well as to regulate the spatial and temporal dynamics of Ca2+signaling at subcellular resolution. Members of the superfamily of EF-hand Ca2+-binding proteins are effective to either attenuate intracellular Ca2+ transients as stochiometric buffers or function as Ca2+ sensors whose conformational change upon Ca2+ binding triggers protein-protein interactions, leading to cell state-specific intracellular signaling events. In the central nervous system, some EF-hand Ca2+-binding proteins are restricted to specific subtypes of neurons or glia, with their expression under developmental and/or metabolic control. Therefore, Ca2+-binding proteins are widely used as molecular markers of cell identity whilst also predicting excitability and neurotransmitter release profiles in response to electrical stimuli. Secretagogin is a novel member of the group of EF-hand Ca2+-binding proteins whose expression precedes that of many other Ca2+-binding proteins in postmitotic, migratory neurons in the embryonic nervous system. Secretagogin expression persists during neurogenesis in the adult brain, yet becomes confined to regionalized subsets of differentiated neurons in the adult central and peripheral nervous and neuroendocrine systems. Secretagogin may be implicated in the control of neuronal turnover and differentiation, particularly since it is re-expressed in neoplastic brain and endocrine tumors and modulates cell proliferation in vitro. Alternatively, and since secretagogin can bind to SNARE proteins, it might function as a Ca2+ sensor/coincidence detector modulating vesicular exocytosis of neurotransmitters, neuropeptides or hormones. Thus, secretagogin emerges as a functionally multifaceted Ca2+-binding protein whose molecular characterization can unravel a new and fundamental dimension of Ca2+signaling under physiological and disease conditions in the nervous system and beyond.  相似文献   
88.
Li Q  Zhu Y  Chu J  Wang Y  Xu Y  Hou Q  Zhang S  Guo X 《Microbiology and immunology》2006,50(12):929-936
A recombinant pertussis DNA vaccine was described here with its immunogenicity and the ability to induce protection against B. pertussis infection in mice. Three immunodominant antigen gene fragments of pertussis, pertussis toxin subunit 1 (pts1), fragments of pertactin (prn) and filamentous hemagglutinin (fha), were recombined as fragment pts1-prn-fha named ppf, and it was cloned to plasmid pVAX1 as pVAX1/ppf. Compared to those injected with pVAX1, the mice injected with pVAX1/ppf significantly elicited more antigen specific antibody anti-PTS1, anti-PRN, anti-FHA and cytokine IL-10, IFN-gamma. When pGM-CSF was coinjected with pVAX1/ppf, the mice showed significantly increases of the three antibodies and cytokine IL-10, IL-4, IFN-gamma and TNF-alpha compared to those injected with pVAX1 only. The mice in group pVAX1/ppf & pGM-CSF, in particular; induced much more anti-PTS1, IL-4 and TNF-alpha than those in group pVAX1/ppf. In the intracerebral mouse protection test, the mice immunized with pVAX1/ppf or pVAX1/ppf & pGM-CSF induced protection to a lethal dose of B. pertussis. The results indicate that recombinant DNA vaccine and pGM-CSF coinjection can induce protective immunity against B. pertussis, demonstrating a valuable method to prevent pertussis.  相似文献   
89.
SCG is a major 6-branched 1,3-beta-D-glucan in Sparassis crispa Fr. SCG shows antitumor activity and also enhances the hematopoietic response in cyclophosphamide (CY)-treated mice. In the present study, the molecular mechanism of the enhancement of the hematopoietic response was investigated. The levels of interferon-(IFN-)gamma, tumor necrosis factor-(TNF-)alpha, granulocyte-macrophage-colony stimulating factor (GM-CSF), interleukin-(IL-) 6 and IL-12p70 were significantly increased by SCG in CY-treated mice. GM-CSF production in the splenocytes from the CY-treated mice was higher than that in normal mice regardless of SCG stimulation. Neutralizing GM-CSF significantly inhibited the induction of IFN-gamma, TNF-alpha and IL-12p70 by SCG. The level of cytokine induction by SCG was regulated by the amount of endogenous GM-CSF produced in response to CY treatment in a dose-dependent manner. The expression of beta-glucan receptors, such as CR3 and dectin-1, was up-regulated by CY treatment. Blocking dectin-1 significantly inhibited the induction of TNF-alpha and IL-12p70 production by SCG. Taken together, these results suggest that the key factors in the cytokine induction in CY-treated mice were the enhanced levels of both endogenous GM-CSF production and dectin-1 expression.  相似文献   
90.
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