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排序方式: 共有214条查询结果,搜索用时 15 毫秒
51.
Liu H Jacobs BS Liu J Prayson RA Estes ML Barnett GH Barna BP 《Cancer immunology, immunotherapy : CII》2000,49(6):319-324
Many of the actions and receptor components of interleukin-13 (IL-13), a pleiotrophic cytokine with immunotherapeutic potential,
are shared with IL-4. Because human low-grade astrocytoma cells express IL-4 receptors and their growth is arrested by IL-4,
we speculated that IL-13 sensitivity and receptor expression might also be present. The purpose of the current study was to
investigate IL-13 receptor components and sensitivity in a series of glial cell lines derived from adult human non-neoplastic
cerebral cortex, low-grade astrocytoma, anaplastic astrocytoma, and glioblastoma multiforme. Unlike peripheral blood lymphocytes
(PBL), glial cells did not express IL-2 receptor γ chain. IL-13 receptor α-1 (IL-13Rα1), however, was present in 11/13 glial
lines and PBL. Deficient cell lines were all glioblastoma-derived. All anaplastic astrocytoma and glioblastoma but not other
glial lines or PBL expressed IL-13 receptor α-2 (IL-13Rα2). In non-neoplastic glia, low-grade, and anaplastic astrocytoma,
IL-13 decreased DNA synthesis, an effect reversible with antibody to IL-4Rα. Results indicate that low-grade astrocytoma cells
resemble non-neoplastic glia in terms of IL-13 sensitivity and IL-4Rα/IL-13Rα1 receptor profile but alterations occur with
malignant progression. Glioblastoma cells were uniformly insensitive to IL-13 and, unlike other glia, failed to phosphorylate
STAT6 after IL-13 challenge. Data suggest that IL-13 and analysis of IL-13 receptors may have clinical application in glial
tumors.
Received: 23 December 1999 / Accepted: 24 February 2000 相似文献
52.
A detailed mapping of Eisenia-tetradecapeptide-immunoreactive neurons in the central and peripheral nervous system combined with quantitative morphological measurements was performed in Eisenia fetida and Lumbricus terrestris. In Eisenia, most labelled neurons were observed in the ganglia of the ventral cord (20.38% of the total cell number of the ganglion) and 15.67% immunoreactive cells occurred in the brain, while 6% of the neurons could be shown in the subesophageal ganglion. In the case of Lumbricus, most immunoreactive cells were found in the subesophageal ganglion (16.17%) and in the ventral ganglia (12.54%). The brain contained 122 ETP-immunoreactive cells (5.6%). The size of the immunoreactive cells varied between 35-75 microm. A small number of Eisenia-tetradecapeptide immunoreactive fibres were seen to leave the ventral ganglia via segmental nerves, and labelled processes could also be observed in the stomatogastric system and the body wall. Labelled axon branches originating from the segmental nerves formed an immunoreactive plexus both between the circular and longitudinal muscle layer and on the inner surface of the longitudinal muscle layer. This inner plexus was especially rich in the setal sac. Among the superficial epithelial cells the body wall contained a significant number of immunoreactive cells. Only a few Eisenia-tetradecapeptide immunoreactive neurons and fibres occurred in the stomatogastric ganglia. In the enteric plexus the number of immunoreactive neurons and fibres decreased along the cranio-caudal axis of the alimentary tract. Eisenia-tetradecapeptide immunoreactive cells were also present among the epithelial cells in the alimentary canal. Some of these cells resembled sensory neurons in the foregut, while others showed typical secretory cell morphology in the midgut and hindgut. 相似文献
53.
After the extirpation of the brain reorganization of the peptidergic (FMRFamide, neuropeptide Y, proctolin) systems was studied in the newly forming cerebral ganglion of the annelid Eisenia fetida. During regeneration, all immunoreactive fibres appear on the 1st-2nd postoperative day. At the beginning of regeneration, immunoreactive neurons and fibres form a mixed structure in the wound tissue. On the 3rd postoperative day, FMRFamide positive and neuropeptide Y-immunoreactive, while on the 7th postoperative day proctolin-immunoreactive neurons appear in the loose wound tissue. From the 25th postoperative day a capsule gradually develops around it. The neurons of the preganglion move to the surface of the newly appearing preganglion. The number of these cells gradually increase, and by the 72th-80th postoperative days the localization and number of peptide-immunoreactive neurons is similar to that in the intact one. The neurons of all examined peptidergic systems may originate from the neuroblasts, situated on the inner and outer surface of the intact ganglia (e.g. suboesophageal and ventral cord ganglia). In addition FMRFamide and proctolin immunoreactive neurons may take their derive by mitotic proliferation from the pharyngeal neurons, too. 相似文献
54.
BACKGROUND: High levels of inflammatory cytokines lead to lung damage in premature newborns. We investigated whether single nucleotide polymorphisms (SNP) of innate immunity cytokine genes influence the length of oxygen supplementation. METHODS: We genotyped 123 very low birth weight (VLBW) infants for the tumour necrosis factor (TNF)- alpha G(-308)A, interleukin (IL)-1beta C(3954)T, IL-6 G(-174)C and IL-10 G(-1082)A SNPs. Genomic DNA was isolated from remnant dried blood samples from the neonates. We tested the association between SNPs and ventilation characteristics using a stepwise multiple regression analysis model. RESULTS: The carrier state of the TNF-alpha G(-308)A allele was associated with a 40-hour longer period of mechanical ventilation (p=0.004) and, on average, an additional 36 hours of oxygen supplementation (p=0.0008). The association was significant after its adjustment for perinatal risk factors for lung damage. CONCLUSIONS:The TNF-alpha G(308)A genotype - which is associated with increased TNF-alpha levels - might influence the supplemental oxygen requirement of VLBW infants. 相似文献
55.
T M Barna H Khan N C Bruce I Barsukov N S Scrutton P C Moody 《Journal of molecular biology》2001,310(2):433-447
Pentaerythritol tetranitrate reductase (PETN reductase) degrades high explosive molecules including nitrate esters, nitroaromatics and cyclic triazine compounds. The enzyme also binds a variety of cyclic enones, including steroids; some steroids act as substrates whilst others are inhibitors. Understanding the basis of reactivity with cyclic enones requires structural information for the enzyme and key complexes formed with steroid substrates and inhibitors. The crystal structure of oxidised and reduced PETN reductase at 1.5 A resolution establishes a close structural similarity to the beta/alpha-barrel flavoenzyme, old yellow enzyme. In complexes of oxidised PETN reductase with progesterone (an inhibitor), 1,4-androstadiene-3,17-dione and prednisone (both substrates) the steroids are stacked over the si-face of the flavin in an orientation different from that reported for old yellow enzyme. The specifically reducible 1,2 unsaturated bonds in 1,4-androstadiene-3,17-dione and prednisone are not optimally aligned with the flavin N5 in oxidised enzyme complexes. These structures suggest either relative "flipping" or shifting of the steroid with respect to the flavin when bound in different redox forms of the enzyme. Deuterium transfer from nicotinamide coenzyme to 1,4-androstadiene-3,17-dione via the enzyme bound FMN indicates 1alpha addition at the steroid C2 atom. These studies rule out lateral motion of the steroid and indicate that the steroid orientation is "flipped" in different redox states of the enzyme. 相似文献
56.
Karolina Nemes Anna Sebestyén ágnes Márk Melinda Hajdu István Kenessey Tamás Sticz Eszter Nagy Gábor Barna Zsófia Váradi Gábor Kovács László Kopper Monika Csóka 《PloS one》2013,8(4)
Modern treatment strategies have improved the prognosis of childhood ALL; however, treatment still fails in 25–30% of patients. Further improvement of treatment may depend on the development of targeted therapies. mTOR kinase, a central mediator of several signaling pathways, has recently attracted remarkable attention as a potential target in pediatric ALL. However, limited data exists about the activity of mTOR. In the present study, the amount of mTOR activity dependent phospho-proteins was characterized by ELISA in human leukemia cell lines and in lymphoblasts from childhood ALL patients (n = 49). Expression was measured before and during chemotherapy and at relapses. Leukemia cell lines exhibited increased mTOR activity, indicated by phospho-S6 ribosomal protein (p-S6) and phosphorylated eukaryotic initiation factor 4E binding protein (p-4EBP1). Elevated p-4EBP1 protein levels were detected in ALL samples at diagnosis; efficacy of chemotherapy was followed by the decrease of mTOR activity dependent protein phosphorylation. Optical density (OD) for p-4EBP1 (ELISA) was significantly higher in patients with poor prognosis at diagnosis, and in the samples of relapsed patients. Our results suggest that measuring mTOR activity related phospho-proteins such as p-4EBP1 by ELISA may help to identify patients with poor prognosis before treatment, and to detect early relapses. Determining mTOR activity in leukemic cells may also be a useful tool for selecting patients who may benefit from future mTOR inhibitor treatments. 相似文献
57.
Lucie P. Pellissier Celso Henrique Alves Peter M. Quinn Rogier M. Vos Naoyuki Tanimoto Ditte M. S. Lundvig Jacobus J. Dudok Berend Hooibrink Fabrice Richard Susanne C. Beck Gesine Huber Vithiyanjali Sothilingam Marina Garcia Garrido André Le Bivic Mathias W. Seeliger Jan Wijnholds 《PLoS genetics》2013,9(12)
Development in the central nervous system is highly dependent on the regulation of the switch from progenitor cell proliferation to differentiation, but the molecular and cellular events controlling this process remain poorly understood. Here, we report that ablation of Crb1 and Crb2 genes results in severe impairment of retinal function, abnormal lamination and thickening of the retina mimicking human Leber congenital amaurosis due to loss of CRB1 function. We show that the levels of CRB1 and CRB2 proteins are crucial for mouse retinal development, as they restrain the proliferation of retinal progenitor cells. The lack of these apical proteins results in altered cell cycle progression and increased number of mitotic cells leading to an increased number of late-born cell types such as rod photoreceptors, bipolar and Müller glia cells in postmitotic retinas. Loss of CRB1 and CRB2 in the retina results in dysregulation of target genes for the Notch1 and YAP/Hippo signaling pathways and increased levels of P120-catenin. Loss of CRB1 and CRB2 result in altered progenitor cell cycle distribution with a decrease in number of late progenitors in G1 and an increase in S and G2/M phase. These findings suggest that CRB1 and CRB2 suppress late progenitor pool expansion by regulating multiple proliferative signaling pathways. 相似文献
58.
Landouria omphalostoma n. sp. is described from northern Yunnan, China. The new species is placed in the genus Landouria Godwin-Austen, 1918 based on the presence of tuberculated flagellum and swollen basal part in the bursa copulatrix, and on the absence of dart sacs and mucous glands. L. omphalostoma n. sp. is characterized by a horizontal aperture of the shell which is unique in the genus. This feature resembles those of only two other camaenid/bradybaenid taxa, species of the Chinese genus Pseudaspasita Möllendorff, 1902 and species of the Japanese genus Coelorus Pilsbry, 1900. This is the first verified record of the genus in China and the easternmost record of Landouria. This paper provides the taxonomic ground work for further studies of the repeated evolution of a horizontal aperture. 相似文献
59.
The genital anatomy of Orcula jetschini (Romania), Orcula zilchi (Bulgaria), and Orcula wagneri (Albania) is described. Based on anatomical features (morphology of the penial caecum) shell characters (sculpture and shape) and unpublished molecular data the genus Orcula is subdivided into three subgenera. Orcula zilchi was classified within the monotypic subgenus Orcula (Hausdorfia)
subgen. n.; Orcula jetschini, Orcula wagneri, and Orcula schmidtii were classified to Orcula (Illyriobanatica)
subgen. n. (type species: Pupa schmidtii) whereas the other Orcula species remain in the nominotypical subgenus. Orcula (Hausdorfia) is known from South-Eastern Bulgaria and North-Western Turkey, Orcula (Illyriobanatica) inhabits Western Romania, North-Western Greece, Albania, Macedonia, Kosovo, and Montenegro. The nine species of Orcula (Orcula) are known mainly from the Alps and the Western Carpathians (from Eastern France to Eastern Hungary and Slovakia).The occurrence of only one Orcula species namely Orcula jetschini is verified from Romania. Available information suggests that data on the Romanian occurrence of Orcula dolium and Orcula gularis were based on wrongly identified specimens. Sphyradium dobrogicum (=Orcula dobrogica) is considered as a synonym of Sphyradium doliolum. 相似文献
60.
A. Janeczko I. Tóbiás A. Skoczowski F. Dubert G. Gullner B. Barna 《Biologia Plantarum》2013,57(1):169-173
Brassinosteroids are known to protect plants against various abiotic and biotic stresses, however, very limited information is available about the role of progesterone. Therefore the effects of Pseudomonas syringae pv. syringae (P.s.) wild type strain 61, its hrcC mutant, and the saprophytic P. fluorescens (P.f.) strain 55 were investigated in wild type Arabidopsis thaliana cv. Columbia and its rbohF knock-out mutant, with and without progesterone pre-treatment. The reactions of wild type and rbohF mutant Arabidopsis to bacterial inoculations were similar, although 2 h after injection of P.s. a larger increase of electrolyte leakage was measured in wild type than in rbohF knockout mutant leaves. The hrcC mutant caused weak necrotic symptoms and increased leakage in both types of Arabidopsis, although to a much lesser extent than P.s. The P.f. did not induce any visible symptom, but slightly increased the electrolyte leakage in both types of Arabidopsis. Inoculation by all Pseudomonas bacteria led to significant alterations in photosystem 2 efficiency as compared to control plants. Pre-treatment of leaves with progesterone diminished the necrotic symptoms, the electrolyte leakage and improve the efficiency of photosystem 2 caused by Pseudomonas bacteria. 相似文献