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1.
During the life cycle of heterothallic tetrapolar Agaricomycetes such as Lentinula edodes (Berk.) Pegler, the mating type system, composed of unlinked A and B loci, plays a vital role in controlling sexual development and resulting formation of the fruit body. L. edodes is produced worldwide for consumption and medicinal purposes, and understanding its sexual development is therefore of great importance. A considerable amount of mating type factors has been indicated over the past decades but few genes have actually been identified, and no complete genetic structures of L. edodes B mating-type loci are available. In this study, we cloned the matB regions from two mating compatible L. edodes strains, 939P26 and 939P42. Four pheromone receptors were identified on each new matB region, together with three and four pheromone precursor genes in the respective strains. Gene polymorphism, phylogenetic analysis and distribution of pheromone receptors and pheromone precursors clearly indicate a bipartite matB locus, each sublocus containing a pheromone receptor and one or two pheromone precursors. Detailed sequence comparisons of genetic structures between the matB regions of strains 939P42, 939P26 and a previously reported strain SUP2 further supported this model and allowed identification of the B mating type subloci borders. Mating studies confirmed the control of B mating by the identified pheromone receptors and pheromones in L. edodes.  相似文献   
2.
Phospholipases A2 (PLA2) are a family of enzymes that catalyze the hydrolysis of the sn-2 ester bond of glycerophospholipids liberating lysophospholipids and free fatty acids; important second messengers involved in atherogenesis. Plasma PAF-acetylhydrolase (PAF-AH) or Lp-PLA2 is a Ca2+-independent PLA2 which is produced by monocyte-derived macrophages and by activated platelets, and circulates in plasma associated with lipoproteins. PAF-AH catalyzes the removal of the acetyl/short acyl group at the sn-2 position of PAF and oxidized phospholipids produced during inflammation and oxidative stress. In humans, PAF-AH is mainly associated with small dense LDL and to a lesser extent with HDL and with lipoprotein(a). PAF-AH is N-glycosylated prior to secretion which diminishes its association with HDL raising the question of its distribution between the proatherogenic LDL vs the antiatherogenic HDL. Hypercholesterolemic patients have higher plasma PAF-AH activity which is reduced upon hypolipidemic therapy. PAF-AH specific inhibitor darapladib stabilizes human and swine plaques, therefore challenging the antiatherogenic potential of PAF-AH shown in small animal models.  相似文献   
3.
目的:通过研究GX1-rmhTNFα对动物重要生命功能的影响,观察其主要药效学以外的药理作用,为临床研究和安全用药提供信息。方法:分别取大鼠、小鼠肌肉注射,测试GX1-rmhTNFα对动物中枢神经系统、心血管系统、呼吸系统的影响。结果:GX1-rmhTNFα三个剂量组对动物中枢神经系统,呼吸系统,心血管系统无明显影响,与生理盐水对照组比较P〉0.05。结论:在本实验中,GX1-rmhTNFα对小鼠的中枢神经系统无明显影响,对大鼠呼吸系统,心血管系统无显著性影响,提示其不良反应小。  相似文献   
4.
Summary Cultured endothelial cells derived from bovine calf pulmonary artery were subjected to a variety of fixatives and stained with 1% Alcian blue 8GX at pH 2.59 to 3.26. Within this range of pH, interphase nuclei and especially mitotic figures were (a) strongly stained in cells fixed with 10% formalin (phosphate buffered or unbuffered) or 2.5% buffered glutaraldehyde, (b) weakly stained or unstained in cells fixed in formaldehyde containing divalent cations, and (c) unstained in cells fixed in acetic acid-containing fluids. However, optimal nuclear staining with Alcian blue under the conditions of this study was judged to be achieved after fixation with neutral phosphate buffered 10% formalin. Endothelial cell cytoplasm exhibited a similar fixative-dependent staining. At pH 2.59 the cytoplasm of interphase cells fixed in formaldehyde (containing no divalent cations) or glutaraldehyde remained unstained; however, at higher pH cytoplasmic staining did occur and it increased as pH increased. In contrast, when these latter fixatives were employed the cytoplasm of mitotic cells stained at all pH levels tested. In cultured endothelial cells after appropriate fixation, 1% Alcian blue 8GX (pH 2.59) was found to possess the ability to stain nuclei with a selectivity and intensity that compared favorably to those of the Feulgen reaction or Heidenhain iron hematoxylin but without the latters’ length and complexity. Therefore, this procedure may provide a rapid, simple, and selective method for visualizing interphase nuclei or mitotic figures, or both in the majority of cultured cells.  相似文献   
5.
We compared the staining performance, dye content, solubility, and visual absorption maximum of two batches of alcian blue pyridine variant and of five batches of alcian blue 8GX (C.I. 74240). Whenever possible, we also compared results to those obtained with the same dye batches produced at an earlier date to provide information concerning dye stability. Both alcian blue pyridine variant batches were of high dye content, stable, of satisfactory solubility, and performed well in both the routine Mowry mucin stain and in the critical electrolyte concentration (CEC) stain. Of the five alcian blue 8GX samples, some were also of appropriate dye content, were sufficiently stable, and gave good staining in the two procedures. Two batches, however, were unstable, and three batches were unsatisfactory in staining performance and solubility in the CEC stain. Consequently alcian blue pyridine variant is a superior substitute for alcian blue 8GX.  相似文献   
6.
目的:设计、合成酪氨酸(Tyr)修饰的肿瘤血管靶向肽GX1,研究^131I标记短肽Tyr-GX1在荷人胃癌裸鼠体内的生物学分布与显像,探讨^131I-Tyr-GX1短肽作为肿瘤血管靶向诊治药物的可能性。方法:利用Iodogen碘标法对Tyr-GX1进行131I标记,检测其标记率和体内外稳定性;建立荷人胃癌裸鼠动物模型,尾静脉注射标记肽,分别进行体内生物学分布实验和肿瘤显像实验,结果用PASW Statistics18.0统计软件进行分析。结果:1).纸层析法结果计算表明,^131I-Tyr-GX1肽的标记率和放化纯均达90%以上;24 h稳定性测试表明,^131I-Tyr-GX1在室温下存放以及与人血清、鼠血清、PBS等溶液混合,其标记率仍然都维持在90%左右,说明其具有良好的体内外稳定性;2).荷瘤裸鼠体内生物学分布研究显示:标记肽在荷瘤裸鼠双肾放射性计数测量最高;其次是肝脏、肿瘤等组织;脑、骨、肌肉组织放射性计数含量较低,给药24 h时,肿瘤/肌肉(T/M)、肿瘤/血液(T/Bl)、肿瘤/脑组织(T/Br)的放射性比值分别是5.78、4.06和23.01;3).体内SPECT显像结果显示:尾静脉注射^131I-Tyr-GX1肽后4 h肿瘤部位已开始显影,并随时间的延长,显像逐渐清楚,至18 h时,肿瘤显像最清晰。结论:应用Iodogen碘标法成功标记Tyr-GX1短肽;尾静脉注射^131I-Tyr-GX1后,肿瘤部位可以出现放射性浓聚,表明^131I-Tyr-GX1短肽可以靶向结合于肿瘤部位,有望成为新一种胃肠道肿瘤诊断与治疗的药物。  相似文献   
7.
Immature fruit of tomato, Lycopersicon esculentum (Celebrity), was examined to observe the cuticle, its interface with the epidermis, and the general histology of the outer exocarp. Paraffin sections were stained first with Bismarck brown Y. Structures already stained in various hues of brown were stained again with either azure B, aluminum hematoxylin and alcian blue 8GX, or the periodic acid-Schiff (PAS) reaction. Bismarck brown-azure B displayed the cuticle in strong contrast with subjacent tissue; however, nuclei were not easily identified at low magnification. Bismarck brown-hematoxylinalcian blue produced a sharply contrasted combination of yellow cuticle, bright blue cell walls and purple nuclei. Nuclei stained purple with hematoxylin were easily identified at × 100. Bismarck brown-PAS stained the cuticle golden brown and subjacent tissues magenta red. Surprisingly, epidermal cells stained specifically and intensely with PAS while pretreatment with an aldehyde blockade and omission of periodic acid prevented staining of all other tissues.  相似文献   
8.
The distribution of a glial cell-associated glycoprotein, glionexin (GX), on sensory receptors of the adult cricket Acheta domesticus is described, using the monoclonal antibody 5B12 as an immunohistochemical probe. GX was previously shown to be widely distributed in the embryo and to persist in the postembryonic to adult central nervous system. Here we demonstrate that it is restricted in the adult periphery to three subclasses of mechano-receptor sensilla: large socketed hair mechanoreceptors, their associated campaniform sensilla, and chordotonal organs. GX was not detected in photoreceptors, chemoreceptors, or other mechanoreceptors. The pattern of distribution differs significantly within the three subclasses of mechanoreceptors. In the hair and campaniform receptors GX is restricted to the extracellular space among glial cells clustered around the axon hillock region, but in chordotonal organs it surrounds the scolopidium at the tip of dendrites. The highly restricted distribution of GX in the periphery suggests possible functions that include mechanical stability of the sensory apparatus and ionic homeostasis in the respective neuronal spike-generating regions. The developmental modulation of GX expression is taken to imply multiple functions for the molecule during the life of the insect. 1994 John Wiley & Sons, Inc.  相似文献   
9.
目的:以肿瘤血管靶向肽GX1修饰的人血清白蛋白(HSA)作为吲哚菁绿(ICG)的载体,合成近红外荧光探针GX1-HSA-ICG,研究其作为近红外荧光探针在荷人胃癌裸鼠活体中的靶向成像能力。方法:以HSA作为ICG的载体,通过化学修饰与GX1共价连接,合成GX1-HSA-ICG纳米颗粒探针;使用SDS-PAGE对探针合成进行鉴定;采用探针与脐静脉内皮细胞HUVEC以及与肿瘤细胞共培养的脐静脉内皮细胞Co-HUVEC进行结合和竞争抑制试验,验证探针和Co-HUVEC细胞结合的特异性;利用小动物活体成像系统对皮下荷胃癌小鼠进行近红外荧光活体成像,验证探针在体内的胃癌靶向性。结果:成功合成GX1-HSA-ICG。细胞结合与竞争抑制实验显示GX1-HSA-ICG可与Co-HUVEC细胞特异性结合;荷瘤小鼠活体成像也显示出GX1-HSA-ICG较ICG有更长体内的循环时间,并且胃癌组织局部较HSA-ICG有更强的聚集。结论:本研究成功合成了胃癌血管靶向肽GX1修饰的HSA为荧光染料载体的胃癌血管靶向探针,成功对荷胃癌裸鼠进行了活体成像。使用HSA为载体的探针较单纯使用ICG的肿瘤局部滞留能力显著提高,GX1增加了探针的胃癌靶向特异性。该探针在胃癌的早期诊断和抗肿瘤血管生成治疗评估中具有潜在的应用价值。  相似文献   
10.
We compared the staining performance, dye content, solubility, and visual absorption maximum of two batches of alcian blue pyridine variant and of five batches of alcian blue 8GX (C.I. 74240). Whenever possible, we also compared results to those obtained with the same dye batches produced at an earlier date to provide information concerning dye stability. Both alcian blue pyridine variant batches were of high dye content, stable, of satisfactory solubility, and performed well in both the routine Mowry mucin stain and in the critical electrolyte concentration (CEC) stain. Of the five alcian blue 8GX samples, some were also of appropriate dye content, were sufficiently stable, and gave good staining in the two procedures. Two batches, however, were unstable, and three batches were unsatisfactory in staining performance and solubility in the CEC stain. Consequently alcian blue pyridine variant is a superior substitute for alcian blue 8GX.  相似文献   
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