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61.
目的 探讨单纯性肾囊肿的组织起源。方法 20例囊液标本取自12位男性和8位女性,采用两种方法:(1)测定囊液中钠(Na^ )、钾(K^ )、氯(Cl^-)、尿素氮(BUN)、肌酐(Cr)、葡萄糖(Glu)、总蛋白(TP)等物质的浓度,并与血浆中的浓度相比较;(2)选用两种高选择定位于不同肾小管节段的酶标植物血凝素,四叶莲凝集素和jacalin凝集素,对单纯性肾囊肿标本进行组织化学研究。四叶莲凝集素定位于近端肾小管,而jacalin凝集素定位于远端肾小管和集合管。结果 (1)标本中Na^ 、K^ 、Cl^-、BUN、Cr、Glu的浓度与血浆中浓度基本相等,而血浆中总蛋白的浓度则高于囊液中浓度;(2)15例囊肿内衬上皮的四叶莲凝集素染色均呈强阳性,而jacalin凝集素染色有7例为阴性,另8例为部分弱阳性。结论 单纯性肾囊肿可能起源于近端肾小管。  相似文献   
62.
The effect of stone-wool has been studied in both in vivo long term sequential and in vitro methods in male Sprague-Dawley rats. Stone-wool was administered by single intratracheal instillation and the lungs were examined after 1, 3 and 6 months of exposure by morphological methods. UICC crocidolite was applied as a positive control. In addition, the effects of both fibres were examined in primary cultures of alveolar macrophages (AM) and type II pneumocytes (T2) by morphological, biochemical and immunological methods. By the end of 6 months stone-wool induced moderate pulmonary interstitial inflammation and fibrosis without progression, whereas crocidolite induced progressive interstitial inflammation and fibrosis as a function of time. Although stone-wool inhibited phagocytosis, it did not induce serious membrane damage to the cells examined and did not destroy their ultrastructure. It significantly reduced the activity of Cu,Zn/superoxide dismutase (SOD) and alkaline phosphatase (AP) in alveolar macrophages and significantly decreased the activity of AP and gamma-glutamyl transpeptidase (GGT) in type II pneumocytes. Crocidolite, on the other hand, decreased the activity of all enzymes (glutathione peroxidase, GSH-Px; glutathione reductase, GSH-Rd) of glutathione metabolism as well as alkaline phosphatase in alveolar macrophages. It decreased the activity of all enzymes in type II pneumocytes, except for Cu,Zn/SOD. On exposure to stone-wool, the production of inflammatory proteins, macrophage chemoattractant protein-1 (MCP-1) and macrophage inhibitory protein-1alpha (MIP-1alpha) increased in both cultured cells but did not reach the level induced by crocidolite. Our results suggested that stone-wool is less toxic than crocidolite. Whether it is carcinogenic or not, is still an open question.  相似文献   
63.
Carbohydrate Binding Protein 35 (CBP35) is a galactose-specific lectin found in the nucleus and cytoplasm of mouse 3T3 fibroblasts. In these cultures, the level of expression and nuclear localization of CBP35 was correlated with the proliferative state of the cells. CBP35 is also found in human fibroblasts. We have compared the expression and localization of CBP35 in human fibroblasts of different replicative capacities: young (passage 11), intermediate (passage 19), and old (passage 33) SL66 cells, and fibroblasts derived from a patient with Werner's syndrome. The results indicate that the expression of CBP35 in cells with either age-acquired or congenital replicative deficiencies was unresponsive to serum stimulation, in contrast with that found in young normal human fibroblasts and in 3T3 cells.  相似文献   
64.
Antinutritional properties of plant lectins.   总被引:9,自引:0,他引:9  
Lectins are carbohydrate binding (glyco)proteins which are ubiquitous in nature. In plants, they are distributed in various families and hence ingested daily in appreciable amounts by both humans and animals. One of the most nutritionally important features of plant lectins is their ability to survive digestion by the gastrointestinal tract of consumers. This allows the lectins to bind to membrane glycosyl groups of the cells lining the digestive tract. As a result of this interaction a series of harmful local and systemic reactions are triggered placing this class of molecules as antinutritive and/or toxic substances. Locally, they can affect the turnover and loss of gut epithelial cells, damage the luminal membranes of the epithelium, interfere with nutrient digestion and absorption, stimulate shifts in the bacterial flora and modulate the immune state of the digestive tract. Systemically, they can disrupt lipid, carbohydrate and protein metabolism, promote enlargement and/or atrophy of key internal organs and tissues and alter the hormonal and immunological status. At high intakes, lectins can seriously threaten the growth and health of consuming animals. They are also detrimental to numerous insect pests of crop plants although less is presently known about their insecticidal mechanisms of action. This current review surveys the recent knowledge on the antinutritional/toxic effects of plant lectins on higher animals and insects.  相似文献   
65.
Research Institute of Experimental and Clinical Therapy, Ministry of Health and Social Security of the Republic of Georgia, Tbilisi. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 1, pp. 24–26, January, 1992.  相似文献   
66.
分泌期反复流产子宫内膜凝集素结合特性探讨   总被引:1,自引:0,他引:1  
本文通过生物素分别标记的双花藕豆凝集素(DBA)、大豆凝集素(SBA)、麦胚凝集素(WGA)及荆豆凝集素(UEA-1)与子宫内膜的反应,应用S-P法研究28例无明显原因反复流产的分泌期子宫内膜糖复合物的变化及与其组织形态学分期的相关性。结果:①宫内膜迟延发生率为39.3%(11/28);②四种凝集素中只有DBA与子宫内膜的结合表现出阶段特异性。着床期,DBA宫内膜结合率增强,且与宫内膜组织形态学分期呈有意义的直线正相关(r=0.404,P<0.05)。提示与DBA特异结合的子宫内膜上的糖复合物与孕卵着床有关,这种特异结合可以作为评价分泌期子宫内膜分化成熟的一项指标  相似文献   
67.
Summary Irradiation of the murine fetal inner ear is known to produce damage both to the vestibular and cochlear parts in the adult mouse. Fluorescein-labelled lectins were used to reveal possible differences in the glycoconjugate content between normal and irradiated inner ears. In the vestibular part, the otoconia showed the highest uptake of labelled sugars. This uptake was weaker after irradiation when compared to non-irradiated specimens. The type I hair cells in the ampulla and in the utricle showed a weaker uptake, but no labelling was demonstrated in the type II hair cells compared to the non-irradiated controls. In the cochlear part of the inner ear almost no uptake of fluorescent-binding lectins could be demonstrated in the irradiated groups except for in the tectorial membrane. In the endolymphatic sac no uptake was shown after prenatal irradiation. These findings are discussed and correlated to the already known damage of the inner ear following prenatal irradiation.  相似文献   
68.
Each of the structures integrating the sense of smell in mammals has a different degree of development, even in the so‐called macrosmatic animals, according to the capacity of the olfactory system to detect thousands of different chemical signals. Such morphological diversity implies analogous physiological variation. The study of the accessory olfactory system, also known as the vomeronasal system, is a useful way to analyze the heterogeneity of the sense of smell. Macrodissection and microdissection methods as well as conventional histology and immunohistochemistry protocols were used to study aspects of the vomeronasal organ and the accessory olfactory bulbs in dogs. Observations regarding the end of the anterior part of the vomeronasal duct have been emphasized. Both lectins, Ulex europaeus agglutinin I and Lycopersicum esculentum agglutinin, and one G protein, Gαi2, show a similar pattern of binding in the sensory epithelium of the vomeronasal organ and in the vomeronasal nerve and glomerular layers of the accessory olfactory bulb, whereas the expression of protein Gαo was not observed. Taken together, our results emphasize the contribution of comparative data to our understanding of the vomeronasal system function. Anat Rec, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
69.
The morphological involution and histochemical changes of the Syrian hamster ( Mesocricetus auratus ) epididymis induced by a short light period were investigated. Under short-day conditions, the epididymis showed marked morphological changes including a decrease in luminal diameter, disappearance of spermatozoa, increase of interductal tissue, increase of intraepithelial lipofuscin deposits, the presence of phagolysosomes in the principal cells and macrophage-like cells, and a considerable modification of most clear cells. With lectin histochemistry changes were found in the glycoconjugates of principal cells of the regressed epididymis, either a decrease (PNA, WGA, HPA and DBA) or an increase (MAA) in the affinity of lectins to the Golgi area, or a decrease (HPA) or an increase (PNA) in lectin binding to stereocilia. Both morphological and histochemical results showed that, under this light condition, the cauda epididymidis presented the most prominent alterations, and that the epididymis showed increased absorptive activity and a decreased synthesis of glycoproteins. All these changes are probably due to the decrease in testosterone levels.  相似文献   
70.
Cao H  Crocker PR 《Immunology》2011,132(1):18-26
Sialic-acid-binding immunoglobulin-like lectins, siglecs, are important immune receptors expressed widely in mammals. A unique feature of siglecs is their ability to bind sialylated glycans and transmit signals to immune cells. The CD33-related siglecs (CD33rSiglecs) form a major subfamily of the siglecs, containing a large, rapidly evolving group of genes that expanded in mammals through an inverse duplication event involving a primordial cluster of siglec genes over 180 million years ago. Humans express a much larger set of CD33rSiglecs than mice and rats, a feature that can be explained by a dramatic loss of CD33rSiglec genes in rodents. Most CD33rSiglecs have immune receptor tyrosine-based inhibitory motifs and signal negatively. Interestingly, novel DAP-12-coupled 'activating' CD33rSiglecs have been identified, such as siglec-14 and siglec-16, which are paired with the inhibitory receptors, siglec-5 and siglec-11, respectively. The evolution of these activating receptors may have been driven in part by pathogen exploitation of inhibitory siglecs, thereby providing the host with additional pathways by which to combat these pathogens. Inhibitory siglecs seem to play important and varied roles in the regulation of host immune responses. For example, several CD33rSiglecs have been implicated in the negative regulation of Toll-like receptor signalling during innate responses; siglec-G functions as a negative regulator of B1-cell expansion and appears to suppress inflammatory responses to host-derived 'danger-associated molecular patterns'. Recent work has also shown that engagement of neutrophil-expressed siglec-9 by certain strains of sialylated Group B streptococci can suppress killing responses, thereby providing experimental support for pathogen exploitation of host CD33rSiglecs.  相似文献   
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