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71.
Nicotinic acid adenine dinucleotide phosphate (NAADP+) is an intracellular second messenger releasing Ca2+ from intracellular stores in different cell types. In addition, it is also active in triggering [Ca2+](i) increase when applied extracellularly and various underlying mechanisms have been proposed. Here, we used hP2Y(11)-transfected 1321N1 astrocytoma cells to unequivocally establish whether extracellular NAADP+ is an agonist of the P2Y(11) receptor, as previously reported for beta-NAD+ [I. Moreschi, S. Bruzzone, R.A. Nicholas, et al., Extracellular NAD+ is an agonist of the human P2Y11 purinergic receptor in human granulocytes, J. Biol. Chem. 281 (2006) 31419-31429]. Extracellular NAADP+ triggered a concentration-dependent two-step elevation of [Ca2+](i) in 1321N1-hP2Y(11) cells, but not in wild-type 1321N1 cells, secondary to the intracellular production of IP(3), cAMP and cyclic ADP-ribose (cADPR). Specifically, the transient [Ca2+](i) rise proved to be related to IP(3) overproduction and to consequent Ca2+ mobilization, while the sustained [Ca2+](i) elevation was caused by the cAMP/ADP-ribosyl cyclase (ADPRC)/cADPR signalling cascade and by influx of extracellular Ca2+. In human granulocytes, endogenous P2Y(11) proved to be responsible for the NAADP+-induced cell activation (as demonstrated by the use of NF157, a selective and potent inhibitor of P2Y(11)), unveiling a role of NAADP+ as a pro-inflammatory cytokine. In conclusion, we provide unequivocal evidence for the activation of a member of the P2Y receptor subfamily by NAADP+.  相似文献   
72.
Mantle cell lymphomas (MCL), characterized by the t(11;14)(q13;q32), frequently carry secondary genetic alterations such as deletions in chromosome 17p involving the TP53 locus. Given that the association between TP53-deletions and concurrent mutations of the remaining allele is weak and based on our recent report that the Hypermethylated in Cancer 1 (HIC1) gene, that is located telomeric to the TP53 gene, may be targeted by deletions in 17p in diffuse large B-cell lymphoma (DLBCL), we investigated whether HIC1 inactivations might also occur in MCL. Monoallelic deletions of the TP53 locus were detected in 18 out of 59 MCL (31%), while overexpression of p53 protein occurred in only 8 out of 18 of these MCL (44%). In TP53-deleted MCL, the HIC1 gene locus was co-deleted in 11 out of 18 cases (61%). However, neither TP53 nor HIC1 deletions did affect survival of MCL patients. In most analyzed cases, no hypermethylation of the HIC1 exon 1A promoter was observed (17 out of 20, 85%). However, in MCL cell lines without HIC1-hypermethylation, the mRNA expression levels of HIC1 were nevertheless significantly reduced, when compared to reactive lymph node specimens, pointing to the occurrence of mechanisms other than epigenetic or genetic events for the inactivation of HIC1 in this entity.  相似文献   
73.
Polydesmidae are represented in Taiwan by seven species in two genera. Neither of the genera is endemic to Taiwan, but six of the species are, including five new: Nipponesmus minorsp. n., Epanerchodus bispinosussp. n., Epanerchodus curtigonopussp. n., Epanerchodus flagellifersp. n. and Epanerchodus pinguissp. n. In addition, the diagnosis of the hitherto enigmatic genus Nipponesmus Chamberlin & Wang, 1953 is refined vis-à-vis the especially similar, Central Asian, Siberian and Eastern European genus Schizoturanius Verhoeff, 1931, chiefly based on new material of the type-species Nipponesmus shirinensis Chamberlin & Wang, 1953; this species is adequately redescribed and represents still another Taiwanese endemic. A key to all three currently known species of Nipponesmus Chamberlin & Wang, 1953 is given. The highly speciose Central to East Asian genus Epanerchodus Attems, 1901 is represented in Taiwan by five species, all keyed, including Epanerchodus orientalis Attems, 1901, which is long known to be highly variable in Japan and found particularly polymorphous and apparently allochthonous in Taiwan. The following synonymy is formalized: Epanerchodus orientalis orientalis Attems, 1901 = Epanerchodus orientalis takakuwai Verhoeff, 1913, syn. n. The genus Usbekodesmus Lohmander, 1932 is formally synonymized with Epanerchodus Attems, 1901, syn. n., resulting in the following new formal transfers: Epanerchodus redikorzevi (Lohmander, 1932), Epanerchodus swatensis (Golovatch, 1991), Epanerchodus varius (Geoffroy & Golovatch, 2004), Epanerchodus anachoretus (Golovatch, 1986), Epanerchodus buddhis (Golovatch, 1986), Epanerchodus occultus (Golovatch, 1986), Epanerchodus sacer (Golovatch, 1987), Epanerchodus theocraticus (Golovatch, 1990) and Epanerchodus theosophicus (Golovatch, 1986), all comb. n. ex Usbekodesmus. The distributions of all seven species of Polydesmidae occurring in Taiwan are mapped and discussed.  相似文献   
74.
In caulonemal filaments of the mossPhyscomitrella patens (Hedw.), red light triggers a phytochrome-mediated transient depolarisation of the plasma membrane and the formation of side branch initials. Three-electrode voltage clamp and ion flux measurements were employed to elucidate the ionic mechanism and physiological relevance of the red-light-induced changes in ion transport. Current-voltage analyses indicated that ion channels permeable to K+ and Ca2+ are activated at the peak of the depolarisation. Calcium influx evoked by red light coincided with the depolarisation in various conditions, suggesting the involvement of voltage-gated Ca2+ channels. Respective K+ fluxes showed a small initial influx followed by a dramatic transient efflux. A role of anion channels in the depolarising current is suggested by the finding that Cl efflux was also increased after red light irradiation. In the presence of tetraethylammonium (10 mM) or niflumic acid (1 M), which block the red-light-induced membrane depolarisation and ion fluxes, the red-light-promoted formation of side branch initials was also abolished. Lanthanum (100 M), which inhibits K+ fluxes and part of the initial Ca2+ influx activated by red light, reduced the development of side branch initials in red light by 50%. The results suggest a causal link between the red-light-induced ion fluxes and the physiological response. The sequence of events underlying the red-light-triggered membrane potential transient and the role of ion transport in stimulus-response coupling are discussed in terms of a new model for ion-channel interaction at the plasma membrane during signalling.Abbreviations [Ca2+]c cytosolic free Ca2+ - I-V current-voltage - E equilibrium potential - Pr red-light-absorbing phytochrome form - Pr far-red-light-absorbing phytochrome form - SPQ 6-methoxy-l-(3-sulphonatopropyl)quinolinium - TEA tetraethylammonium  相似文献   
75.
Summary -Chymotrypsin has been modified with poly(ethylene glycols) and proxanols, block-copolymers of poly(propylene oxide) and poly(ethylene oxide). These conjugates were several-fold more thermostable and showed high catalytic activity at elevated concentrations of water-miscible organic cosolvents (alcohols and dimethyl sulfoxide) which caused inactivation of free (non-modified) -chymotrypsin.  相似文献   
76.
Footrot (FR) is a common, contagious bacterial disease of sheep that results in lameness and significant economic losses for producers. We previously reported that sheep affected with FR have lower whole-blood (WB) selenium (Se) concentrations and that Se supplementation in conjunction with routine control practices accelerates recovery from FR. To determine whether oral Se-yeast administered at supranutritional levels (>4.9 mg Se/week) alters the ability of sheep to resist or recover from FR infection, 60 ewes with and 60 ewes without FR were drenched once weekly for 62.5 weeks with 0, 4.9, 14.7, or 24.5 mg organic Se-yeast (30 ewes per treatment group). Footrot prevalence and severity were measured at 0, 20, 28, 40, and 60 weeks of Se supplementation. Genomic expression of eight WB-neutrophil genes for selenoproteins and seven WB-neutrophil genes for proteins involved in innate immunity was determined at the end of the treatment period using SYBR Green and quantitative polymerase chain reaction methodology. Supranutritional Se-yeast supplementation successfully increased Se status in sheep but did not prevent FR. Supranutritional Se-yeast supplementation increased WB-neutrophil expression of genes involved in innate immunity: l-selectin, interleukin-8 receptor, and toll-like receptor 4, which were or tended to be lower in ewes affected with FR. Furthermore, supranutritional Se-yeast supplementation altered the expression of selenoprotein genes involved in innate immunity, increasing selenoprotein S and glutathione peroxidase 4 and decreasing iodothyronine deiodinases 2 and 3. In conclusion, supranutritional Se-yeast supplementation does not prevent FR, but does alter WB-neutrophil gene expression profiles associated with innate immunity, including reversing those impacted by FR.  相似文献   
77.
Assessing the distribution of 16S rRNA gene sequences within a biological sample represents the current state-of-the-art for determination of human gut microbiota composition. Advances in dissecting the microbial biodiversity of this ecosystem have very much been dependent on the development of novel high-throughput DNA sequencing technologies, like the Ion Torrent. However, the precise representation of this bacterial community may be affected by the protocols used for DNA extraction as well as by the PCR primers employed in the amplification reaction. Here, we describe an optimized protocol for 16S rRNA gene-based profiling of the fecal microbiota.  相似文献   
78.
Molecular Biology Reports - Targeted genome editing using CRISPR/Cas9 is a promising technology successfully verified in various plant species; however, it has hardly been used in plant cell...  相似文献   
79.
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