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991.
Abstract: The human neuroblastoma cell line SH-SY5Y, maintained at confluence for 14 days, released [3H]-noradrenaline ([3H]NA) when stimulated with either the muscarinic receptor agonist methacholine or bradykinin. The major fraction of release was rapid, occurring in <10 s, whereas nicotine-evoked release was slower. When the extracellular [Ca2+] ([Ca2+]e) was buffered to ~50–100 nM, release evoked by nicotine was abolished, whereas that in response to methacholine or bradykinin was reduced by ~50% with EC50 values of ?5.46 ± 0.05 M and ?7.46 ± 0.06 M (log10), respectively. Methacholine and bradykinin also produced rapid elevations of both inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] and intracellular free [Ca2+] ([Ca2+]i). These elevations were reduced at low [Ca2+]e and under these conditions the EC50 values for peak elevation of [Ca2+]i were ?6.00 ± 0.14 M for methacholine and ?7.95 ± 0.34 M for bradykinin (n = 3 for all EC50 determinations). At low [Ca2+]e, depletion of nonmitochondrial intracellular Ca2+ stores with the Ca2+-ATPase inhibitor thapsigargin produced a transient small elevation of [Ca2+]i and a minor release of [3H]NA. At low [Ca2+]e, thapsigargin abolished elevation of [Ca2+]i in response to methacholine and bradykinin and completely inhibited their stimulation of [3H]NA release. It is proposed, therefore, that Ca2+ release from Ins(1,4,5)P3-sensitive stores is a major trigger of methacholine- and bradykinin-evoked [3H]NA release in SH-SY5Y cells. 相似文献
992.
993.
Two DNA sequences specific for the canine Y chromosome 总被引:1,自引:0,他引:1
Data are presented on the characterization of two nucleotide sequences found exclusively in the DNA of male dogs. In polymerase chain reactions (PCRs) of canine genomic DNA with a decanucleotide primer of arbitrary sequence (OP-W17), two nucleotide segments (650 and 990 bp) were amplified only from male samples, whereas a number of other fragments between 400 and 2500 bp in size were amplified from both male and female samples. The two male-specific segments were cloned and sequenced, and terminal 24mer oligonucleotide primer pairs were synthesized. PCR with these specific primer pairs resulted in amplification of the two male-specific sequences only from DNA samples of 34 male dogs; no product was amplified from 42 samples of females. A segment of the SRY gene previously localized on the Y chromosome could be amplified in DNA samples that had the two new sequences. Eco RI digested genomic male DNA when hybridized with the 650 bp or the 990 bp sequences, resulted in a single band for each on Southern analysis; DNA from females did not yield any bands. Comparisons between the two new sequences and the SRY gene segment revealed no homologies. We concluded that the two new sequences are specific for the canine Y chromosome and do not contain the short characterized segment of the SRY gene. 相似文献
994.
Yukio Oomori Sachiko Okumo Hitoshi Fujisawa Hiromichi Iuchi Katsushi Ishikawa Yohichi Satoh Kazuyuki Ono 《Cell and tissue research》1994,275(2):201-213
Immunohistochemistry has been used to demonstrate tyrosine hydroxylase (TH), dopamine--hydroxylase (DBH), phenylethanolamine N-methyltransferase (PNMT), neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP) immunoreactivities, and acetylcholinesterase (AChE) activity was demonstrated in rat adrenal glands. The TH, DBH, NPY and VIP immunoreactivities and AChE activity were observed in both the large ganglion cells and the small chromaffin cells whereas PNMT immunoreactivity was found only in chromaffin cells, and not in ganglion cells. Most intraadrenal ganglion cells showed NPY immunoreactivity and a few were VIP immunoreactive. Numerous NPY-immunoreactive ganglion cells were also immunoreactive for TH and DBH; these cells were localized as single cells or groups of several cells in the adrenal cortex and medulla. Use of serial sections, or double and triple staining techniques, showed that all TH- and DBH-immunoreactive ganglion cells also showed NPY immunoreactivity, whereas some NPY-immunoreactive ganglion cells were TH and DBH immunonegative. NPY-immunoreactive ganglion cells showed no VIP immunoreactivity. AChE activity was seen in VIP-immunopositive and VIP-immunonegative ganglion cells. These results suggest that ganglion cells containing noradrenaline and NPY, or NPY only, or VIP and acetylcholine occur in the rat adrenal gland; they may project within the adrenal gland or to other target organs. TH, DBH, NPY, and VIP were colocalized in numerous immunoreactive nerve fibres, which were distributed in the superficial adrenal cortex, while TH-, DBH- and NPY-immunoreactive ganglion cells and nerve fibres were different from VIP-immunoreactive ganglion cells and nerve fibres in the medulla. This suggests that the immunoreactive nerve fibres in the superficial cortex may be mainly extrinsic in origin and may be different from those in the medulla. 相似文献
995.
996.
Identification of the catalytic histidine residue participating in the charge-relay system of carboxypeptidase Y.
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G. Jung H. Ueno R. Hayashi T. H. Liao 《Protein science : a publication of the Protein Society》1995,4(11):2433-2435
The essential histidine residue of carboxypeptidase Y (CPY) was modified by a site-specific reagent, a chloromethylketone derivative of benzyloxycarbonyl-L-phenylalanine. The single modified histidine residue was converted to N tau-carboxy-methyl histidine (cmHis) upon performic acid oxidation. A peptide containing cmHis was isolated from the tryptic-thermolytic digest. Based on the amino acid composition and sequence analysis, the peptide is shown to be Val-Phe-Asp-Gly-Gly-cmHis-MetO2-Val-Pro, which was derived from CPY cleaved by trypsin at Arg 391 and thermolysin at Phe 401, and thus His 397 was modified. This histidine residue has been implicated previously by X-ray analysis to participate in the charge-relay system of CPY. 相似文献
997.
R. G. Novy J. P. Helgeson 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,89(6):783-786
Somatic hybrids between a potato virus Y (PVY) resistant Solanum etuberosum clone and a susceptible diploid potato clone derived from a cross between S. tuberosum Gp. Tuberosum haploid US-W 730 and S. berthaultii were evaluated for resistance to PVY. All but one of the tested somatic hybrids were significantly more resistant than cultivars Atlantic and Katahdin. However, none was as resistant as the S. etuberosum parent. One hexaploid somatic hybrid, possibly the product of a triple-cell fusion involving one S. etuberosum protoplast and two haploid x S. berthaultii protoplasts, was as susceptible to PVY infection as the cultivars. Tetraploid progeny of the somatic hybrids, obtained from crosses with Gp. Tuberosum cultivars, were neither as resistant as the maternal somatic hybrid parent, nor as susceptible as the paternal cultivar parent. It appears that the introgression of PVY resistance from (1EBN) S. etuberosum into (4EBN) S. tuberosum (EBN-endosperm balance number) will be successful through the use of somatic hybridization and subsequent crosses of the somatic hybrids back to S. tuberosum. 相似文献
998.
Kairemo Kalevi J. A. Ljunggren Kaj Wahlström Torsten Stigbrand Torgny Strand Sven-Erik 《Cell biochemistry and biophysics》1994,24(1-3):293-300
Tumor stroma contains much fibrin and monoclonal antifibrin antibody targeting is possible in tumors. In this study, nude
mouse human ovarian carcinoma xenograft specimens were investigated after treatment with90Y-labeled monoclonal antifibrin antibody Fab fragment or with90Y-labeled OC125-monoclonal antibody F(ab′)2 fragments. The mice received the radioimmunotherapy activity either intratumorally, intraperitoneally, or intravenously.
Beta-camera imaging (BCI) is a novel device for studying activity distribution in tissue specimens and, together with immunohistochemistry
(IHC) with OC125, antifibrin, anticarcinoembryonic antigen, anti-cytokeratin, and anti-placental alkaline phosphatase antibodies,
was used for correlation of activity distribution of tissue specimens. These results were in concordance: Antigen distribution
measured with IHC and radioactivity distribution were similar with the same antibodies, antifibrin, and OC125: However, these
antigens demonstrated rather different distribution. Tissue studies revealed that activity was concentrated also in the necrotic
tumor tissue, indicating that cell death was also caused by radiation. Differences in the tumor cell morphology were observed
using different routes of administration. With BCI, it is possible to quantitate activities in frozen sections (microdosimetry),
and these results were in concordance with absolute activities as measured by tissue sampling and well-counting. Three-dimensional
reconstruction of tissue slices combined with radioactivity distribution measured with BCI allows estimation of total absorbed
radiation dose in tumor after an appropriate dose planning. 相似文献
999.
本文用免疫细胞化学ABC法,研究15—38周龄人胎视网膜神经肽Y免疫反应(NeuropeptideYimmunorective,NPY-IR)神经元(以下称NPY-IR细胞)的发育。结果表明:①胎龄15周视网膜中央部已出现不同类型的NPY-IR细胞:位于黄斑及其周围外核层的为NPY-IR视锥细胞;位于内核层最内一列的为NPY-IR无长突细胞位于节细胞层的可能为NPY-IR移位无长突细胞或节细胞;内核层和节细胞层的NPY-IR细胞的突起均分布在内网层的第1亚层。②胎龄24周后,NPY-IR视锥细胞完全消失。③随着视网膜的发育,内核层和节细胞层的NPY-IR细胞数量增多,突起增粗增长,胞体分布由中央部扩展到周边部,其中内核层NPY-IR细胞的密度呈现从中央部向周边部逐渐降低的分布方式,节细胞层NPY-IR细胞则多数集中分布在视网膜的边缘和黄斑之间,形成较高密度的环状区。 相似文献
1000.
Somatic Hybrids Between Potato and S. berthaultii Show Partial Resistance to Soil‐Borne Fungi and Potato Virus Y
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Oumèma Nouri‐Ellouz Mohamed Ali Triki Rania Jbir‐Koubaa Assawer Louhichi Safa Charfeddine Noureddine Drira Radhia Gargouri‐Bouzid 《Journal of Phytopathology》2016,164(7-8):485-496
Three tetraploid somatic hybrid lines produced by protoplast fusion between a dihaploid potato, Solanum tuberosum, cultivar BF15 and the wild potato species Solanum berthaultii were evaluated here for their response to different soil‐borne pathogens, that is Fusarium solani, Pythium aphanidermatum and Rhizoctonia solani as well as to infection by potato virus Y (PVY). Both hybrid and BF15 plants grown in vitro were inoculated with the tested pathogen strains, that is R. solani, P. aphanidermatum, or F. solani. The growth level and disease severity index of these plants were compared to the susceptible commercial cultivar Spunta. A better growth of inoculated hybrid plants and restricted disease symptoms were observed in comparison with the commercial plants. Under glasshouse conditions and after inoculation with R. solani and P. aphanidermatum, improved resistance of the hybrid plants to these pathogens was confirmed. Indeed, these plants showed no significant damage following inoculation and a better development in R. solani‐infected plants. The susceptibility of the hybrid tubers to R. solani, P. aphanidermatum, and to F. solani infection was also determined. A significant reduction of tissue colonisation was observed in all the hybrid lines compared to the cultivated cultivars. The STBc and STBd hybrids also showed improved resistance to the PVY ordinary strain (PVYo) under glasshouse conditions. 相似文献