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1.
Mallory bodies represent cytokeratin-rich inclusion bodies which occur characteristically but not exclusively in human alcoholic liver disease and experimentally in mice during chronic intoxication with drugs. We report the first in vitro cell system of Mallory body induction. In clone 9 rat hepatocytes stably transfected to express an ER-retained T126M-aquaporin-2 (AQP2), on the mean 40% of the cells contained cytokeratin-rich inclusion bodies. By electron microscopy, their structure corresponded to that of genuine Mallory bodies. Such inclusion bodies were not detectable in clone 9 rat hepatocytes stably expressing a Golgi apparatus/lysosome-retained E258K-aquaporin-2. Proteasome inhibition increased the number of Mallory body-containing T126M-AQP2-expressing clone 9 hepatocytes to 60% on average. Proteasome inhibition in non-transfected, cytokeratin meshwork-forming clone 9 hepatocytes resulted in Mallory body formation on average in 6% of cells. Collectively, these data suggest that in the described in vitro cell system, Mallory body formation is induced by the presence of non-native protein conformers and point to the involvement of the proteasomal digestive system. The here reported in vitro system will be useful in studies about the biogenesis and progression of Mallory bodies, their relationship to aggresomes, and the role of inclusion bodies in the pathogenesis of cell damage.  相似文献   

2.
Rhodamine B staining in conjunction with fluorescence microscopy is shown to demonstrate Mallory bodies. Mallory body morphology, localization, and distribution in hepatocytes from griseofulvin-fed mice, human hepatoma, and human alcoholics were similar to those observed in the same tissues after conventional staining methods for Mallory bodies. The presence of these inclusions was further confirmed by specific cytochemical localization with indirect immunoperoxidase labeling, horseradish peroxidase labeling, and electron microscopy. Other tinctorial or histochemical procedures previously used for keratin or prekeratin (modified Mallory stain, Kreyberg method, Pauly method for histidine) also stained Mallory bodies for study with white light microscopy but with decreasing sensitivity respectively. Mallory bodies from mouse and human liver both appear to contain a keratin-like moiety. This entity may be simply, rapidly, and permanently stained with rhodamine B, and selectively and reproducibly demonstrated with fluorescence microscopy.  相似文献   

3.
Mice fed griseofulvin, an antibiotic with antimicrotubular activity, formed hepatocellular aggregates of intermediate filaments, which resembled those associated with human alcoholic liver disease. These aggregates, termed Mallory bodies, were isolated from both human and mouse liver and the composition of these structures compared. Electrophoretic analysis indicated that the mouse filaments were composed of four major polypeptides (51,000, 47,000, 37,000, and 36,000 daltons). Human Mallory bodies possessed a similar number of components but of different molecular weights (56,000, 51,000, 50,000, and 38,000 daltons). Guinea pig antisera prepared against both whole human Mallory bodies and the major human polypeptide (56,000 daltons) crossreacted with mouse Mallory body material in both immunochemical and immunocytochemical systems. Our findings suggest that the two filament systems possess similar biochemical and immunological properties.  相似文献   

4.
Mallory's alcoholic hyalin in hepatocytes was found also in other diseases and is now referred to as Mallory bodies. Data concerning their histochemical, immuno and electron microscopic properties are partly contradictory. In this study, early stages of Mallory bodies reacted strongly with configurational technics for myosins; affinity tended to decrease when material with the properties of keratohyalin and the matrix of stratum corneum was formed. Thus, many Mallory bodies contained histochemically distinct myoid and keratin-like proteins. Electron microscopists demonstrated thick and thin filaments resembling contractile systems in Mallory bodies; the failure of immunologists to visualize actomyosin may be due to the heterogeneity of these proteins. The currently popular term prekeratin has been applied to a variety of substances extracted from epidermis, hoof and hair under different conditions. The prekeratin of recent immunofluorescence studies seems to contain mainly epidermin and low molecular matrix proteins; both were studied extensively by chemists. Epithelial filaments, including tonofibrils and contractile fibrils regarded as a subgroup of myofibrils, were well known half a century ago, but were banished by electron microscopy. Observations in this study and data on epidermal actomyosin indicate that different proteins of the k-m-e-f group can indeed coexist in epithelial cells. The formation and resolution of Mallory bodies can be regarded as an example of the well known shifts of epithelial cells between secretory and keratinizing states.  相似文献   

5.
Summary Mallory's alcoholic hyalin in hepatocytes was found also in other diseases and is now referred to as Mallory bodies. Data concerning their histochemical, immuno and electron microscopic properties are partly contradictory. In this study, early stages of Mallory bodies reacted strongly with configurational technics for myosins; affinity tended to decrease when material with the properties of keratohyalin and the matrix of stratum corneum was formed. Thus, many Mallory bodies contained histochemically distinct myoid and keratin-like proteins. Electron microscopists demonstrated thick and thin filaments resembling contractile systems in Mallory bodies; the failure of immunologists to visualize actomyosin may be due to the heterogeneity of these proteins. The currently popular term prekeratin has been applied to a variety of substances extracted from epidermis, hoof and hair under different conditions. The prekeratin of recent immunofluorescence studies seems to contain mainly epidermin and low molecular matrix proteins; both were studied extensively by chemists. Epithelial filaments, including tonofibrils and contractile fibrils regarded as a subgroup of myofibrils, were well known half a century ago, but were banished by electron microscopy. Observations in this study and data on epidermal actomyosin indicate that different proteins of the k-m-e-f group can indeed coexist in epithelial cells. The formation and resolution of Mallory bodies can be regarded as an example of the well known shifts of epithelial cells between secretory and keratinizing states.  相似文献   

6.
Studies of the sub-cellular location of storage triacylglycerol (TAG) synthesis in developing embryos of oilseed rape (Brassica napus L.) show that there is heterogeneity of the endoplasmic reticulum (ER) with respect to the enzymes of lipid synthesis. The enzymes of TAG synthesis were detected in two membrane fractions (equilibrium densities 1.05 and 1.10 g· ml?1) isolated by sucrose-density-gradient centrifugation of homogenates from developing rape embryos. The synthesis of TAG by the lowdensity membranes has not been reported previously and was found in this study because the sucrose density gradients began at only 10% (w/w) sucrose. The pattern of activity of the enzymes involved in the synthesis of TAG in the higher-density fraction closely matched the marker enzymes for the ER; lyso-phosphatidylcholine acyltransferase and cytidine diphosphate-choline:diacylglycerol cholinephosphotransferase. The activity of the ER marker enzymes in the low-density membrane fraction, however, was very much lower when compared to those involved in the synthesis of TAG. Analysis of the lipids extracted from the low-density fraction revealed it contained about 50 mol% TAG compared with 15 mol% in the bulk ER, which may account for the low density of the membranes in this fraction. The possibility that the low-density membranes were the result of contamination of ER by oil bodies was ruled out by the use of oleosins as a marker for oil bodies. It is suggested that the low-density membranes are derived from a domain of the ER which is involved in the formation and secretion of TAG.  相似文献   

7.
通过Mallory和HE染色,对光肩星天牛Anoplophora glabnpenn脑部显微结构进行了观察.结果表明,光肩星天牛的脑由前脑、中脑、后脑三部分组成.前脑叶髓层包括一对蕈形体、一个中央体、一个脑桥体和一对附叶,其中每个蕈形体仅有一个帽状的蕈体冠.中脑触角叶较大,由九簇放射状排列的触角神经束组成,中央的一束较粗,说明其嗅觉发达.后脑较小.  相似文献   

8.
Prolamellar bodies and prothylakoids from etioplasts of wheat ( Triticum aestivum L. cv. Starke II, Weibull) were separated by sucrose density gradient centrifugation. Top-loaded and bottom-loaded sucrose gradients were compared. As a consequence of avoiding long time exposure of the membranes to low sucrose concentrations, separation in bottom-loaded gradients, as compared to separation in top-loaded gradients, resulted in a sharper and more narrow band of prothylakoids, and in better preservation of phototransformable protochlorophyllide, especially in the prothylakoids. In bottom-loaded gradients, the prothylakoids were found concentrated in a band at a density of 1.20 g'ml−1. The prolamellar bodies were found at a density of 1.17 g'ml−1. In top-loaded gradients the prothylakoids were found at a lower density than the prolamellar bodies. The prothylakoid fraction contained about 60% of the recovered protochlorophyllide and about 85% of the recovered protein. Absorption and fluorescence emission spectra revealed a higher amount of phototransformable protochlorophyllide, in relation to non-phototransformable, in the prolamellar body fraction than in the prothylakoid fraction. Polyacrylamide gel electrophoresis indicated a high proportion of protochlorophyllide reductase in the prolamellar bodies. Chloroplast ATPase (CF1) was found predominantly in the prothylakoid fraction. Thus, our results strongly indicate the presence of phototransformable protochlorophyllide in the prolamellar bodies proper, while the main bulk of proteins are located in the prothylakoids.  相似文献   

9.
Lung tissue obtained from fetal rabbits of 23 days gestational age was maintained in organ culture to study the in vitro formation of lamellar body phospholipids. During the culture period, the epithelium of the prealveolar ducts of the explants differentiated to form type II pneumonocytes. After 8 days in culture, the explants were harvested, homogenized, and two lamellar body fractions were isolated by sucrose density gradient centrifugation. The lamellar body fraction which best retained the distinct multilamellar structure was recovered at the interface between a solution of buffer without sucrose and buffer containing 0.41 m sucrose. The phospholipid compositions of both lamellar body fractions were similar to those reported for lamellar bodies and surfactant isolated from fetal rabbit lung, with the exception of a slightly higher phosphatidylethanolamine content. The disaturated phosphatidylcholine content of the lamellar body fractions, expressed as a percentage of total lipid phosphorus, was not influenced by the presence of palmitate in the medium.  相似文献   

10.
Intracytoplasmic hyaline bodies in malignant cells from an aspirate of a liver mass are suggestive of hepatocellular carcinoma. Such inclusions were studied by light and electron microscopy and by immunocytochemistry in fine needle aspirates from five cases of hepatocellular carcinoma. Seen by light microscopy, the inclusions were round or ovoid and were surrounded by a prominent halo. By both light and electron microscopic immunocytochemistry, the hyaline bodies showed negative staining for alpha-fetoprotein, alpha-1-antitrypsin and cytokeratin. Ultrastructurally, they were not membrane bound and were composed of filamentous, finely granular material, resembling the early stages of Mallory bodies.  相似文献   

11.
应用梯度离心和超速离心浓缩获得部分提纯的病毒制剂,产量约为7.45g/kg病叶提纯的病毒制剂的紫外吸收曲线呈典型的核蛋白吸收曲线,OD260/OD242和OD260/OD280的比值分别为1.24和1.38。病毒粒子呈线状,宽13—14nm,长度主要分布于250—300nm和550—700nm之间,1000nm以上的粒子也有检到。病毒外壳蛋白仅由一个分子量约为30Kd的亚基组成。在免疫电镜试验中、病毒粒子与日本WYMV抗血清发生强烈的血清学反应。新鲜病叶的超薄切片中可看到大量风轮体和膜状体。  相似文献   

12.
Import into potato (Solarium tuberosum L. cv. Record) tubers was terminated by removing the sink at its connection with the stolon. The ability of discs of storage tissue from the excised tubers to take up exogenous sugars and convert them to starch was compared with that of discs from untreated tubers from the same plant population. In rapidly-growing control tubers, glucose and fructose were taken up to a greater extent than sucrose, 77% of the glucose being converted to starch within 3 h (compared with 64% and 27% for fructose and sucrose, respectively). These values fell as the tubers aged but the ranking (glucose > fructose > sucrose) was maintained, emphasising a severe rate-limiting step following the import of sucrose into the growing tuber. Sink isolation had little effect on the ability of the storage cells to take up exogenous sucrose across the plasmalemma for up to 7 d after sink isolation. However, the ability of the same cells to convert the sucrose to starch was severely inhibited within 24 h, as was the sensitivity of starch synthesis to turgor. In the case of glucose, sink isolation inhibited both the uptake and the conversion to starch, the latter being inhibited to a greater degree. A detailed metabolic study of tubers 7 d after excision showed that, with sucrose as substrate, 94% of the radioactivity in the soluble sugar pool was recovered in sucrose following sink isolation (92% in control tubers). However, with glucose as substrate, 80% of the radioactivity was recovered as sucrose following tuber excision (28% in control tubers), providing evidence that sucrose synthesis acts as a major alternative carbon sink when starch synthesis is inhibited. In the same tubers, sucrose-synthase activity decreased by 70% following sink isolation, compared with a 45% reduction in ADP-glucose pyrophosphorylase. Activities of UDP-glucose pyrophosphorylase, starch phosphorylase, starch synthase nd both PPi- and ATP-dependent phosphofructokinases remained unchanged. Acid-invertase activity increased fivefold.  相似文献   

13.
1. Lamellar body fractions from dog lung can be separated by a procedure based on differential centrifugation before ultracentrifugation onto a discontinuous sucrose gradient. This fraction yields about 1% of total protein from the homogenate. 2. The different fractions obtained in the isolation were assayed for the measurement of four subcellular marker enzymes: beta-N-acetylglucosaminidase, acid phosphatase, 5'-nucleotidase and succinate dehydrogenase. 3. Lamellar bodies were not contaminated by mitochondria (0.7 succinate dehydrogenase relative specific activity), whereas high specific hydrolase activities were found (beta-N-acetylglucosaminidase and 5'-nucleotidase were enriched 1.8- and 2.8-fold, respectively). 4. The chemical criterion was established by measuring the specific components of lamellar bodies. The lamellar bodies have the highest phospholipid/protein ratio (0.35); cholesterol/protein ratio (0.15) and the highest phosphatidylglycerol percentages (7.9%). 5. The phospholipid composition of lamellar bodies is distributed among phosphatidylcholine (64.5%), phosphatidylethanolamine (11%), phosphatidylglycerol (7.9%), sphingomyelin (4%), phosphatidylserine and phosphatidylinositol (3%), respectively. The remainder were considered as trace amounts (less than 1%).  相似文献   

14.
为了筛选香栓菌Trametes suaveolens的最佳出菇配方,同时对子实体不同生长阶段的生物学发育特征进行研究。本文用杨树、柳树、秸秆木屑作为培养料设置了8种配比,每种分为对照A、测试组B共计16个配方进行筛选,对不同时期的菌丝发育状况进行显微观察。结果柳树木屑、杨树木屑的配方均能成功栽培出香栓菌子实体,开袋后在90%-95%空气湿度、一定散射光、13-18℃的低温刺激下28d原基发育为菇蕾,继续培养28d后子实体成熟。其中配料为柳树木屑97%、蔗糖1%、石灰1%、石膏1%、含水量65%左右的配方出菇率最高,配料为柳树木屑的配方开袋后子实体长势最佳,采用边缘开袋方式最佳。子实体发育过程中,先分化出白色蜂窝状原基,原基依靠孔状结构吸收营养后,在其上层包被形成黑色菇蕾,同时基部开始形成子实层;菇蕾内部生殖菌丝不断分化和发育,体积逐渐膨大,颜色由深变浅,菌丝分化出担子并产生担孢子,最终形成子实体。  相似文献   

15.
Myelin bodies were isolated from the renal cortex of gentamicin-treated rats (100 mg/kg body weight, twice daily for 3 days, i.p.) employing an initial pelleting by differential centrifugation and subsequent flotation on a discontinuous sucrose gradient. These structures were found to contain almost twice as much protein as phospholipid and SDS-polyacrylamide gel electrophoresis revealed the presence of many different polypeptides. All the major phospholipids are present, although myelin bodies contain a considerably higher proportion of phosphatidylinositol, somewhat more phosphatidylcholine and considerably lower percentages of phosphatidylserine and sphingomyelin than do normal renal phospholipids. The fatty acids of myelin body phospholipids are highly saturated (67.3-87.9%) and a striking feature is the occurrence of relatively large amounts of 22:1, presumably erucic acid, especially in sphingomyelin. Myelin bodies contain small amounts of unesterified cholesterol, unesterified dolichol and coenzymes Q9 and Q10.  相似文献   

16.
寒兰的快速繁殖技术   总被引:7,自引:0,他引:7  
以寒兰(CymbidiumkanranMakino)根状茎为外植体,采用B5基本培养基,并附加不同浓度的6-BA、NAA、TDZ(苯基噻二唑基脲-thidiazuron)和S-3307(优康唑-uniconazole),对类原球茎的诱导、继代增殖、分化、生根等进行研究。结果表明:诱导类原球茎的最佳培养基为B5 TDZ0.50mgL-1 NAA0.25mgL-1,诱导率98.3%;继代增殖的最佳培养基为B5 S-33071.0mgL-1 NAA0.2mgL-1 蔗糖3.5%,增殖系数9.4;类原球茎分化的最佳培养基为B5 S-33070.75mgL-1 6-BA1.0mgL-1 NAA0.4mgL-1,分化率87.8%;最佳的生根培养基为1/2B5 NAA0.2mgL-1 活性炭0.05%,生根率达100%。  相似文献   

17.
C G Duck-Chong 《Life sciences》1978,22(22):2025-2030
A simple one-step procedure is described for the isolation of lamellar bodies and their membranous content in high yield from rat lung. A linear sucrose gradient, ranging from 0.9M – 0.2M sucrose, is poured over a sample of homogenate in IM sucrose and the lamellar body fraction if floated to isopycnic equilibrium by high speed centrifugation. When the same procedure is applied to fluid drained from the lungs of newborn lambs or to human amniotic fluid collected late in pregnancy, a fraction is obtained which appears to consist of the membranous content of lamellar bodies in the process of unravelling.  相似文献   

18.
Protein bodies were prepared from the cotyledons of pumpkin (Cucurbita sp.) seeds by employing a nonaqueous isolation method. Both light micrographic examination and the marker enzyme assays have shown that the isolated protein bodies were intact and contamination with other cell organelles or cytoplasmic components was negligible. A proteolytic enzyme catalyzing the limited hydrolysis of carboxymethylated γ′ chain of globulin was found to be present in the protein bodies. The specific activity in the protein body (18 units per milligram protein) was higher than that in the whole cell extract (13 units per milligram protein), indicating that the limited proteolytic enzyme was localized in the protein body.

After lysis of the protein bodies using hypotonic buffer solution, the suborganellar components (matrix, membranes, and crystalloids) were separated by sucrose density gradient centrifugation. The crystalloid was composed of only globulin, a major seed protein. The major proteins of matrix and membrane fractions were shown to have mol wt of approximately 10,000. About 90% of the limited proteolytic activity was found in the matrix region.

  相似文献   

19.
Characterization of the central body of theAzotobacter cyst   总被引:1,自引:0,他引:1  
Filar micrometer measurements of the central body during its conversion to the vegetative cell indicated an initial spherical body of about 1.7 microns in diameter. The central body first increases in diameter then elongates such that its length is 2–2.5 times the diameter. Central bodies supplemented with casein hydrolysate in addition to sucrose formed vegetative cells in only 8 hr instead of the usual 12. Central bodies were quite susceptible to lysis by EDTA-lysozyme or citrate-lysozyme, but relatively insensitive to citrate-EDTA or single employment of EDTA or citrate. Comparative electron microscopy of cysts and central bodies following sonication revealed little alteration in cysts but reduction of central bodies to cellular debris after only 2 min. Central bodies were resistant to bacteriophage adsorption at 0 hr and required about 4 hr incubation before adsorption could occur.This work was supported by U.S.Public Health Service grant AI-05551 from the National Institute of Allergy and Infectious Diseases. Bacteriophage A-22 was kindly provided by Dr. O. Wyss, University of Texas, Austin.  相似文献   

20.
灵芝子实体、菌丝体及孢子粉中多糖成分差异比较研究   总被引:5,自引:0,他引:5  
为探讨灵芝子实体、菌丝体和孢子粉3种材料中多糖成分的差异,分别运用苯酚硫酸法进行多糖含量测定,运用离子色谱分析其酸水解后单糖组成,并运用HPLC分析各多糖图谱及经α-淀粉酶和β-1,3-葡聚糖酶处理后HPLC图谱的变化,结果发现,灵芝菌丝体中多糖含量最高,达到3.81%,孢子粉多糖含量为1.8%,灵芝子实体中多糖含量最低,仅为0.59%;水解后的单糖组成及摩尔比也有差异,子实体的单糖主要为葡萄糖和半乳糖,菌丝体和孢子粉的单糖主要为葡萄糖;HPLC图谱显示3种多糖出峰位置和分子量也不同,酶解效果表明多糖结构也相差较大。各样品多糖对小鼠巨噬细胞RAW264.7释放NO的产量的影响上,菌丝体与子实体多糖都表现出了很好的活性,而孢子粉多糖却呈现出较低活性。实验结果表明灵芝子实体、菌丝体和孢子粉3种材料的多糖成分差异大,在医药保健品使用中应区分使用。  相似文献   

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