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941.
It has been reported that beta2-agonists may potentially exert some anti-inflammatory action in addition to bronchodilation that may contribute to their beneficial effects on asthma control. Bronchial epithelial cells are well known to respond to a range of stimuli by producing various biologically active mediators that can influence airway inflammation. RANTES (regulated on activation, normal T cells expressed and secreted) plays an important role in the pathophysiology of airway inflammation of asthmatics through its chemotactic activity for eosinophils. In this study, the authors investigated whether cytokine-induced RANTES release from BEAS-2B human bronchial epithelial cells could be modulated by beta-agonist isoproterenol (ISO). The possible involvement of c-jun N-terminal kinase (JNK) pathway was also studied. Combination of tumor necrosis factor-alpha and interleukin-1beta (cytokine mix) increased RANTES release from BEAS-2B cells and stimulated JNK activity. Similar to JNK inhibitor SP600125, ISO inhibited not only the production of RANTES but also the activation of JNK pathway in cytokine mix-stimulated BEAS-2B cells. The effect of ISO was mediated by the beta2-adrenoceptor, since it was blocked by ICI 118,551, a selective beta2-receptor antagonist, but not by atenolol, a selective beta1-receptor antagonist. Adenylyl cyclase activator forskolin reproduced the effects of ISO. Isoproterenol was found to inhibit the release of RANTES from the human bronchial epithelial cells, at least in part, through the inhibition of JNK signaling pathway.  相似文献   
942.
Two unique and fascinating properties of carbonate apatite which are well-known in hard tissue engineering, have been unveiled, for the first time, for the development of the simplest, but most efficient non-viral gene delivery device - ability of preventing the growth of crystals needed for high frequency DNA transfer across a plasma membrane and a fast dissolution rate for effective release of DNA during endosomal acidification, leading to a remarkably high transgene expression (5 to 100-fold) in mammalian cells compared to the widely used transfecting agents. Moreover, by modulating the crystal dissolution rate of carbonate apatite through incorporation of fluoride or strontium into it, transfection activity could be dramatically controlled, thus shedding light on a new barrier in the non-viral route, which was overlooked so far. Thus we have developed an innovative technology with significant insights, that would come as a promising tool for both basic research laboratories and clinical settings.  相似文献   
943.
Phospholipase C-type beta2 (PLCbeta2) is expressed in a subset of cells within mammalian taste buds. This enzyme is involved in the transduction of sweet, bitter, and umami stimuli and thus is believed to be a marker for gustatory sensory receptor cells. We have developed transgenic mice expressing green fluorescent protein (GFP) under the control of the PLCbeta2 promoter to enable one to identify these cells and record their physiological activity in living preparations. Expression of GFP (especially in lines with more than one copy integrated) is strong enough to be detected in intact tissue preparations using epifluorescence microscopy. By immunohistochemistry, we confirmed that the overwhelming majority of cells expressing GFP are those that endogenously express PLCbeta2. Expression of the GFP transgene in circumvallate papillae occurs at about the same time during development as endogenous PLCbeta2 expression. When loaded with a calcium-sensitive dye in situ, GFP-positive taste cells produce typical Ca2+ responses to a taste stimulus, the bitter compound cycloheximide. These PLCbeta2 promoter-GFP transgenic lines promise to be useful for studying taste transduction, sensory signal processing, and taste bud development.  相似文献   
944.
TSLC1/IGSF4, an immunoglobulin superfamily molecule, is predominantly expressed in the brain, lungs, and testes and plays important roles in epithelial cell adhesion, cancer invasion, and synapse formation. We generated Tslc1/Igsf4-deficient mice by disrupting exon 1 of the gene and found that Tslc1(-/-) mice were born with the expected Mendelian ratio but that Tslc1(-/-) male mice were infertile. In 11-week-old adult Tslc1(-/-) mice, the weight of a testis was 88% that in Tslc1(+/+) mice, and the number of sperm in the semen was approximately 0.01% that in Tslc1(+/+) mice. Histological analysis revealed that the round spermatids and the pachytene spermatocytes failed to attach to the Sertoli cells in the seminiferous tubules and sloughed off into the lumen with apoptosis in the Tslc1(-/-) mice. On the other hand, the spermatogonia and the interstitial cells, including Leydig cells, were essentially unaffected. In the Tslc1(+/+) mice, TSLC1/IGSF4 expression was observed in the spermatogenic cells from the intermediate spermatogonia to the early pachytene spermatocytes and from spermatids at step 7 or later. These findings suggest that TSLC1/IGSF4 expression is indispensable for the adhesion of spermatocytes and spermatids to Sertoli cells and for their normal differentiation into mature spermatozoa.  相似文献   
945.
Taxonomic status of the zoanthid genera Palythoa and Protopalythoa has been in question for almost a century. Separation of the two genera has been based on traditional morphological methods (colony and polyp form, nematocyst size and form, and number of septa), with Palythoa polyps embedded in a well developed coenenchyme and Protopalythoa polyps standing free and clear of the coenenchyme. Here we sequenced two mitochondrial regions, the cytochrome oxidase I (COI) gene and 16S ribosomal DNA (16S rDNA) genes, from Palythoa and Protopalythoa samples from various parts of the world and performed phylogenetic analyses of the sequence data. The phylogenetic trees for both COI and 16S rDNA from Palythoa and Protopalythoa show four monophyletic groups (designated Palythoa tuberculosa, Palythoa heliodiscus, Palythoa mutuki 1, and Palythoa mutuki 2), with levels of sequence divergence (COI and 16S rDNA divergence approximately 0.0 approximately 1.1%) similar to or lower than that previously found among congeneric species within the closely related genus Zoanthus. Surprisingly, sequence differences among Palythoa tuberculosa, Palythoa mutuki 1, and Palythoa mutuki 2 were negligible (0.0 approximately 0.2% for both COI and 16S rDNA), potentially indicating relationships below the species level. Our sequences align well with the few Palythoa and Protopalythoa sequences reported to date. These findings strongly indicate that our samples represent a minimum of two and possibly up to four species (the Palythoa tuberculosa - P. mutuki 1 - P. mutuki 2 group, and P. heliodiscus) within the genus Palythoa, and that the genus Protopalythoa is erroneous nomenclature.  相似文献   
946.
The spatial distribution of Oncometopia facialis (Signoret) was studied in sweet orange to elaborate sampling plans and decision-making procedure for the control of this sharpshooter in the field. The samplings were carried out fortnightly in a grid design disposition of 100 points (plants) in citrus orchard, with yellow sticky traps. The average number of O. facialis ranged from 0.35 to 1.17 insects/trap, with the I index varying from 0.89 to 1.82. The fit tests to negative binomial, Poisson distribution, I index and Morisita index indicated aggregated distribution of this insect. The b result of Taylor's power law was 1.6382 (t = 2.71; d.f. = 11; P < 0.05). Sampling plans were elaborated with a precision level of 10, 20 and 25% of error in the mean estimation.  相似文献   
947.
Matrix metalloproteinase (MMP)-7, also known as matrilysin, is a "minimal domain MMP" that exhibits proteolytic activity against components of the extracellular matrix (ECM). Matrilysin is frequently overexpressed in human cancer tissues and is associated with cancer progression. Tumorigenesis is a multistep process involving cell growth, invasion, metastasis, and angiogenesis. Matrilysin has been shown to play important roles not only in degradation of ECM proteins, but also in the regulation of several biochemical processes such as activation, degradation, and shedding of non-ECM proteins. This minire-view provides a summary of the current literature on the roles of matrilysin in tumorigenesis with a focus on the roles of modifications of non-ECM proteins by matrilysin and other related MMPs in tumorigenesis. Proteolysis of insulin-like growth factor binding protein by matrilysin results in increased bioavailability of insulin-like growth factors and enhanced cellular proliferation. Matrilysin has also been implicated in the ectodomain shedding of several cell surface molecules. Heparin-binding epidermal growth factor precursor (proHB-EGF) is cleaved by matrilysin into mature HB-EGF, which promotes cellular proliferation. Membrane-bound Fas ligand (FasL) is cleaved into soluble FasL, which increases apoptosis of cells adjacent to tumor cells. E-cadherin is converted to soluble E-cadherin to promote invasion. Tumor necrosis factor (TNF)-alpha precursor is cleaved to release soluble TNF-alpha to increase apoptosis. We propose that these matrilysin-mediated pathways provide the necessary and logical mechanisms to promote cancer progression.  相似文献   
948.
949.
We report here a development of the MultiSite Gateway(TM)-based versatile plasmid construction system applicable for the rapid and efficient preparation of Aspergillus oryzae expression plasmids. This system allows the simultaneous connection of the three DNA fragments inserted in entry clones along with a destination vector in a defined order and orientation. We prepared a variety of entry clones and destination vectors containing promoters, genes encoding carrier-proteins and fusion tags, and selectable markers, which makes it possible to generate 80 expression plasmids for each target protein. Using this system, plasmids for expression of the EGFP fused with the mitochondrial-targeting signal of citrate synthase (AoCit1) were generated. Tubular structures of mitochondria were visualized in the transformants expressing the AoCit1-EGFP fusion protein. This plasmid construction system allows us to prepare a large number of expression plasmids without laborious DNA manipulations, which would facilitate molecular biological studies on A. oryzae.  相似文献   
950.
We investigated a temperature adaptation of Bacillus subtilis 168 in which chromosomal groEL was replaced with a psychrophilic groEL. This strain can grow at 50 degrees C but not at 51 degrees C, a temperature at which wild-type B. subtilis can grow. Using in vivo random mutagenesis by the B. subtilis mutator strain (mutS, mutM, mutY), two thermo-adaptants were isolated from the groEL substituted strain at 52 degrees C. They contained novel amino acid alterations in their ATP binding motif (T93I) and the inter-monomer contact (R285H) region of GroEL. These results suggest that GroEL participates in bacterial temperature adaptation.  相似文献   
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