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31.
L. J. Kennedy K. V. Poulton P. A. Dyer W. E. R. Oilier W. Thomson 《Tissue antigens》1995,46(3):187-195
Abstract: Many new HLA-C locus alleles have recently been identified by DNA sequencing, and a molecular based method for their detection using PCR with sequence specific primers has been reported. However, other methods may be more appropriate for the identification of C locus alleles in larger studies. Here we describe one such system, based on PCR sequence specific oligonucleotide probes, (SSOP) for C locus typing. Advantages of SSOP typing compared to SSP are that it is easier to detect new alleles, more cost effective and less time consuming. We have developed a DNA typing method to identify the broad C locus antigens (including those not yet defined serologically) using a minimum of probes with one amplification. We use a C locus specific sense primer in exon 2 and a consensus antisense primer in exon 3, in a two-step PCR, giving a product of 710 bp. Probes were designed with similar melting temperatures (54–56C) that would identify as many alleles as possible. The method was established using DNA from B lymphoid cell lines of known C locus type, mostly 10th workshop homozygous cell lines, plus as many other sequenced cell lines as possible. The system was able to correctly identify their C locus types using only 26 probes. DNA was tested from a panel of serologically typed individuals which included many different heterozygous combinations. We found a high concordance of results, with all discrepancies being additional antigens identified by molecular typing, filling in serological blanks. We can identify all common heterozygote combinations using this method. 相似文献
32.
大鼠蓝斑内P物质、神经降压肽和生长抑素样神经元的上行投射 总被引:2,自引:1,他引:2
本实验采用HRP逆行追踪与免疫细胞化学相结合的方法,对大鼠蓝斑内P物质(SP)、神经降压肽(NT)、生长抑素(SOM)三种肽能投射神经元的纤维联系及其局部关系进行了探讨。结果证实:1.HRP注射至丘脑或尾壳核后,大鼠蓝斑内均可见到双标记神经元。2.存在SP样和NT样蓝斑—丘脑纤维,前者终止于丘脑腹后核和板内核,后者终止于丘脑板内核。3.蓝斑至尾壳核的投射呈SOM样免疫反应。4.蓝斑内三种肽能投射的起始和终止部位有所不同,其中SP样和NT样神经元主要位于蓝斑后部背侧区,其纤维终于丘脑;而SOM样投射神经元则见于蓝斑前部背侧区,纤维终止于尾壳核。上述肽能通路均为双侧性,而以同侧占优势。5.蓝斑内三种肽能单标记神经元中以NT样免疫反应阳性胞体最为丰富。以上结果表明;蓝斑上行性投射中除含去甲肾上腺素纤维外,还含有SP样、NT样和SOM样纤维,并存在一定的局部定位投射关系。 相似文献
33.
Waanders Gary A.; Lussow Alexander R.; MacDonald H. Robson 《International immunology》1993,5(1):55-61
Reactivity of murine T cells with viral or bacterial superantigensis clearly correlated with the expression of TCR Vßdomains. Thus, T cells responding to the minor lymphocyte stimulatorylocus (Mls-1a) or staphylococcal enterotoxin B (SEB) expresspredominantly TCR Vß6 or Vß8.2 respectively.We have investigated the involvement of the other major variableelement of the TCR, the V domain, in these superantigen responses.Using a panel of anti-TCR V mAbs, It is demonstrated that theTCR V repertoire among superantigen stimulated Vß6+or Vß8.2+ blasts (responding to Mls-1a or SEB respectivelyin vitro) is altered in comparison with anti-CD3 stimulatedcells expressing the same V domains. Furthermore, the TCR Vrepertoire is strongly skewed in TCR Vß8.2 transgenicmice that have undergone extensive peripheral clonal deletionafter SEB injection. These data imply that the V domain influencessuperantigen recognition by sthe TCR. 相似文献
34.
Summary The induction of mitotic recombination in theCDC8 locus was studied in a diploid strain heteroallelic forcdc8 mutations (cdc8-1/cdc8-3); mitotic reversion was studied in strainscdc8-1/cdc8-1 andcdc8-3/cdc8-3. Conversion and reversion did not occur in those cells blocked at the S stage of the cell cycle by exposure to a nonpermissive
temperature. In stationary phase cells irradiated just prior to exposure to temperature stress, the induction of recombinants
was rather low and the induction of revertants was minimal. Conversely, a significant induction ofcdc
+ occurred in logarithmic phase cells subjected to the same treatment. Irradiation of synchronously dividing cultures revealed
that intragenic recombination occurs at all three stages of the cell cycle- G1, S and G2. It was also found that UV-induced gene reversion can occur during the S and G2 stages, but not during the G1 stage of the cell cycle. 相似文献
35.
目的探讨D7S2 1位点在河北汉族人群分布的多态性 ,为DNA指纹数据库的构建及其法医学应用提供基础资料。方法应用MVR PCR方法和聚丙烯酰胺梯度凝胶电泳银染法对 12 4名河北汉族人群无关个体D7S2 1位点进行了快速检测 ,并进行数字编码。结果每一个体平均得到 3 6个数字编码 ,未发现任何两个无关个体所有编码相同 ,两无关个体 3 6个编码相同的机率为 3 .4 8× 10 -18。三种重复单位a 型、t 型和o 型出现的机率分别为 4 8.5 %、4 9.5 %和 2 .1%。该位点杂合度为 0 .9876,非父排除率为 0 .974 6,多态性信息含量为 0 .9872。结论D7S2 1位点在河北汉族人群中具有高度的多态性 ,聚丙烯酰胺梯度凝胶电泳银染法简便、快速 ,具有一定的实用价值 相似文献
36.
目的:为了解广西壮族人群D1S80位点群体遗传资料,方法,使用扩增片段长度多态性(Amp-Flp)和PCR结合聚丙烯酰胺凝电脉及银染技术,对300名文本地区壮族无关个体D1S80位点多态性分析,结果,观察到23个等位基因,74个基因型,杂合度,非交排除率,个体识别力及多态信息含量分别为0.824,0.763,0.968,0.875,其基因频率分布符合Hardy-weinberg定律,对5个家系相关个体分析符合孟德尔定律,结认,该方法具有快速,简便,特异性强,灵敏度高特点。 相似文献
37.
中国北方汉族、维吾尔族、哈萨克族DYS19基因座的遗传多态性 总被引:4,自引:0,他引:4
目的;研究DYS19基因座在中国北方汉族、维吾尔族、哈萨克族群体中的遗传多态性及其法医学应用。方法:应用聚合酶链反应后变性聚丙烯酰胺凝胶电泳分离扩增产物结合银染显带的方法,对101例北方汉族、56例维吾尔族、30例哈萨克族无关男性个体的DYS19基因座进行检测。结果:DYS19基因座在3个群体中共检出5种等位基因,基因频率分布范围分别为0.069-0.594,0.071-0.500,0.100-0.667;个人识别机率分别为0.600,0.675,0.491。χ^2检验表明等位基因分布具有明显的人群差异。家系调查符合单体父系遗传方式。结论:DYS19基因座个人识别机率高,属较高鉴别能力的遗传标记系统,且具有明显的人群分布差异,在法医学及人类遗传学研究中具有重要的应用价值。 相似文献
38.
In chronic experiments on rabbits and rats, parameters of eye homeostasis (intraocular pressure and ocular hydrodynamics) and lungs (water balance and surface-active properties of surfactant) were studied during electrical stimulation of the locus coeruleus against the background of chronic stress induced in rabbits by repeated electrical stimulation of the ventromedial nucleus and in rats by daily immobilization on a platform. Stimulation of the locus coeruleus eliminated ocular hypertension of hypothalamic origin and stress-induced disturbances in surface activity, blood volume, and water balance in the lungs. 相似文献
39.
The GNAS locus is an imprinted site. The α-subunit of the stimulatory G protein (Gsα) and extralarge variant (XLαs) are the two important products of the GNAS locus. The abnormal expression of Gsα is associated with pseudohypoparathyroidism (PHP) and related disorders, including Albright hereditary osteodystrophy (AHO), pseudopseudohypoparathyroidism (PPHP), and progressive osseous heteroplasia (POH). XLαs protein can mimic the catalytic intracellular synthesis of cyclic adenosine monophosphate (cAMP) by Gsα in response to parathyroid hormone (PTH) stimulation, which may be involved in the pathogenesis of PPHP and POH in patients with paternal GNAS defects. A paternally inherited nonsense variant in the first exon of XLαs in an adult patient may be associated with fractures and osteopetrosis. The relationship between the XLαs product of the GNAS locus and bone remodeling may have been overlooked. Here, we summarize the phenotypes of genetic mouse models and clinical cases of XLαs variations and suggest that the abnormal paternal expression of XLαs may be associated with the development of POH and affect osteoblast and osteoclast differentiation. 相似文献
40.
- Intracellular recordings were made in a pontine slice preparation of the rat brain containing the nucleus locus coeruleus (LC). The pressure application of α,β-methylene ATP (α,β-meATP) caused reproducible depolarizations which were depressed by suramin (30 μM) and abolished by suramin (100 μM). Pyridoxal-phosphate-6-azophenyl-2′,4′-disulphonic acid (PPADS; 10, 30 μM) also concentration-dependently inhibited the α,β-meATP-induced depolarization, although with a much slower time-course than suramin. Almost complete inhibition developed with 30 μM PPADS. Reactive blue 2 (30 μM) did not alter the effect of α,β-meATP, while reactive blue 2 (100 μM) slightly depressed it.
- Pressure-applied (S)-α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) also depolarized LC neurones. Kynurenic acid (500 μM) depressed and 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX; 50 μM) abolished the response to AMPA. Suramin (100 μM) potentiated the AMPA effect.
- Pressure-applied noradrenaline hyperpolarized LC neurones. Suramin (100 μM) did not alter the effect of noradrenaline.
- Focal electrical stimulation evoked biphasic synaptic potentials consisting of a fast depolarization (p.s.p.) followed by a slow hyperpolarization (i.p.s.p.). A mixture of D(−)-2-amino-5-phosphonopentanoic acid (AP-5; 50 μM), CNQX (50 μM) and picrotoxin (100 μM) depressed both the p.s.p. and the i.p.s.p. Under these conditions suramin (100 μM) markedly inhibited the p.s.p., but did not alter the i.p.s.p. In the combined presence of AP-5 (50 μM), CNQX (50 μM), picrotoxin (100 μM), strychnine (0.1 μM), tropisetron (0.5 μM) and hexamethonium (100 μM), a high concentration of suramin (300 μM) almost abolished the p.s.p. without changing the i.p.s.p.
- In the presence of kynurenic acid (500 μM) and picrotoxin (100 μM), PPADS (30 μM) depressed the p.s.p. Moreover, the application of suramin (100 μM) to the PPADS (30 μM)-containing medium failed to cause any further inhibition. Neither PPADS (30 μM) nor suramin (100 μM) altered the i.p.s.p.
- It was concluded that the cell somata of LC neurones are endowed with excitatory P2-purinoceptors. ATP may be released either as the sole transmitter from purinergic neurones terminating at the LC or as a co-transmitter of noradrenaline from recurrent axon collaterals or dendrites of the LC neurones themselves.