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1.
A T Marshall 《Tissue & cell》1983,15(2):311-315
Regions of the fat body of larvae of Chaetophyes compacta and Pectinariophyes sp. (Machaerotidae, Homoptera) which are closely associated with mycetomes have been analysed by electron probe X-ray microanalysis. It is shown that cells in these regions contain electron probe X-ray microanalysis. It is shown that cells in these regions contain electron dense granules which are rich in copper and sulphur. These two elements occur in the atomic ratio of 3:2 respectively. It is conjectured that copper may be bound to a sulphur containing metallothionein and that the granules represent either the end products of copper detoxification or serve as copper stores for synthesis of enzymes and macromolecules by the mycetomal symbionts.  相似文献   

2.
The morphology of cells of strain Muggia, a slightly halophilic leptospire, was examined by the negative staining technique.The ultrastructure of the cells was rather similar to that of cells of Leptonema illini, i. e. the cells possessed cytoplasmic tubules. The basal complex of their flagella, however, was similar to the corresponding part of flagella on Gramnegative bacteria. The interior of the cells was densely packed with inclusions, except for the two outermost wavelengths at each end where these inclusions were absent.X-ray microanalysis showed that the inclusions contained sodium and chlorine as their main constituents. The inclusions disappeared upon storage of the cultures at room temperature.  相似文献   

3.
After injection in the rat of soluble neptunium salt, the distribution of this element was studied at the subcellular level by electron microscopy and electron probe microanalysis. Abnormal structures have been observed by electron microscopy in the nuclei of hepatocytes, and the same structures have also been observed in the nuclei of the proximal tubules cells of the kidney. These structures are formed of clusters of very small and dense particles, several nanometers in diameter. The clusters are localized in the central part of the nuclei and they are separate from nucleoli and heterochromatin. Electron probe X-ray analysis of this cluster have shown that they contain neptunium associated with phosphorus. In the cell containing neptunium inclusions, other non specific lesions are also observed (nuclear pycnosis, mitochondrial depletion).  相似文献   

4.
The interaction between iron and copper has been discussed in association with human health and diseases for many years. Ceruloplasmin, a multi-copper oxidase, is mainly involved in iron metabolism and its genetic defect, aceruloplasminemia (ACP), shows neurological disorders and diabetes associated with excessive iron accumulation, but little is known about the state of copper in the brain. Here, we investigated localization of these metals in the brains of three patients with ACP using electron microscopes equipped with an energy-dispersive x-ray analyzer. Histochemically, iron deposition was observed mainly in the basal ganglia and dentate nucleus, and to lesser degree in the cerebral cortex of the patients, whereas copper grains were not detected. X-ray microanalysis identified two types of iron-rich particles in their brains: dense bodies, namely hemosiderins, and their aggregated inclusions. A small number of hemosiderins and most inclusions contained a significant amount of copper which was enough for distinct Cu x-ray images. These copper-containing particles were observed more frequently in the putamen and dentate nucleus than the cerebral cortex. Coexistence of iron and copper was supported by good correlations in the molecular ratios between these two metals in iron-rich particles with Cu x-ray image. Iron-dependent copper accumulation in iron-rich particles may suggest that copper recycling is enhanced to meet the increased requirement of cuproproteins in iron overload brain. In conclusion, the iron-rich particles with Cu x-ray image were found in the ACP brain.  相似文献   

5.
Copper has been demonstrated in the feet of slugs exposed to the molluscicide copper sulfate. Using the scanning electron microscope coupled with X-ray microanalysis, copper was localized to the epithelium of the foot. Under the transmission electron microscope the subcellular distribution of copper was obtained by precipitating the molluscicide with potassium ferrocyanide. The reaction product was both electron opaque and insoluble in the preparative media. The precipitate was localized in the zonula adhaerens and septate junctions between adjacent epithelial cells. Reaction product was also present in some of the pinocytotic vesicles of the epithelial cells. The identity of the reaction product was confirmed using X-ray microanalysis.  相似文献   

6.
C. M. Pueschel 《Protoplasma》1995,189(1-2):73-80
Summary The red alga,Antithamnion kylinii Gardner, was found to have needle-shaped inclusions about 10 m long and less than 0.4 m thick. They ranged in abundance from one or a few in young cells to hundreds in fully enlarged cells. Under polarized light, the inclusions were birefringent, indicating crystallinity. Solubility tests suggested that the inclusions were composed of calcium oxalate: they dissolved in 1 N hydrochloric acid and in a saturated solution of aqueous cupric acetate, but they were not soluble in 10 N acetic acid or 5.25% sodium hypochlorite. X-ray microanalysis confirmed the presence of calcium. Calcium oxalate crystals were present in cells of indeterminate axes, but cells of determinate lateral filaments lacked them. Light and electron microscopic study demonstrated that the crystals were associated with the parietal cytoplasm. Calcium oxalate crystals were also present inA. defectum Kylin, but they were not found in ten more distantly related taxa.  相似文献   

7.
The presence of intranuclear and cytoplasmic inclusions in cells of embryogenic callus and developing embryoids from tissue cultures of Panax quinquefolius L. was described. These cellular structures were not found in non-embryogenic cells. The size of intranuclear and cytoplasmic inclusions seemed to be related to the developmental status of the cell.  相似文献   

8.
1921年,Molish首先在光镜下发现植物叶片细胞核中有一种晶体状的内含物(见Weintraub等[1])。后来人们陆续在某些动、植物的细胞核中观察到了这种结构[2—4],并称之为核内含体(intranuclearinclusions)。Bigazzi[3]曾在45种桔梗科植物的细胞中看到了核内含体。但在离体培养的植物细胞中发现内含体的报道很少,至今仅在榛子组织培养分生细胞中看到了类似的结构[5]。我们在对西洋参体细胞胚胎发生进行超微结构研究的过程中发现,在胚性愈伤组织和胚状体细胞的核和细胞质…  相似文献   

9.
Pinealocytes of the cotton rat (Sigmodon hispidus) often contain large (2-6 micron diameter) intracytoplasmic inclusions, the function of which is not known. These inclusions may represent nucleolus-like bodies, mineral deposits, secretory products or viral inclusions. In this study these inclusions were classified as type A, B or C inclusions based on the amount of electron-dense material interspersed within the finely granular material comprising the bulk of these inclusions. Each type of inclusion was analyzed by X-ray microanalysis and enzymatic proteinaceous digestion. X-ray microanalysis of these inclusions differed both quantitatively and semiquantitatively from that of human or gerbil pineal concretions, the latter two of which are extracellular deposits. Pronase, a proteolytic enzyme, digested the electron-dense material only after longer times of tissue exposure to this enzyme in contrast to the easily digested, finely granular matrix-like material of these inclusions. Such intrapinealocytic inclusions have only been observed in the cotton rat. Their functional significance remains unknown.  相似文献   

10.
Summary Mineral distribution in the roots of wheat (Triticum aestivum L. cv. Wheaton) was investigated using X-ray microanalysis of bulk frozen hydrated roots in SEM and of freeze substituted sections in TEM. Results obtained using the two methods agreed reasonably well. A total often elements were detected: Na, Mg, Si, P, S, Cl, K, Ca, Mn, and Fe. Of these Si, P, Ca, and Mn were incorporated into biomineralized structures. Silica was deposited in the endodermal walls in the older parts of the root. Silicon was also detected in the large central metaxylem lumina in the basal zone of the root, and in the smaller peripheral metaxylem and the immediately contiguous pericycle and outer parenchyma cells bridging the small metaxylem vessels to the endodermal layer. In the basal zone of the root some of the inner cortical cells contained intracellular electron opaque deposits. These were associated with the cell walls, had non-opaque inclusions and microanalysis revealed that they consisted of calcium, phosphorus and manganese.Abbreviations A apical zone of root - M midzone of root - B basal zone of root - SEM scanning electron microscope - TEM transmission electron microscope  相似文献   

11.
K. Hausmann  B. Walz 《Protoplasma》1979,99(1-2):67-77
Summary In the cytoplasm of the marine ciliateEuplotes vannus, there exist two conspicuous types of membrane bound inclusions: 1. irregularly shaped crystals which are highly anisotropic; 2. globular lithosomes characterized by concentrically arranged layers of deposits which exhibit only faint birefringence. Normally, both structures form distinct accumulations. Energy dispersive X-ray microanalysis of these accumulations reveals a high content of calcium and phosphorus, besides magnesium, sulphur and chlorine. Analysis of cell areas devoid of the inclusions show significantly lower calcium- and phosphorus-peaks.
  相似文献   

12.
Histoehemical evidence is presented that cells, described as 'tanning cells', in the hydroid Laomedea flexuosa contain an orthodihydroxyphenol oxidase and transfer this enzyme to the perisarc. The detection of copper in the tanning cells provides further evidence for the presence of phenol oxidase, a copper-containing enzyme. Evidence is presented that this enzyme and the orthodihydroxyphenol, dopamine, are stored together in the same 1mu diameter spherical inclusions. The enzyme and orthodihydroxyphenolic substrate appear to be transferred together to the perisarc where it is thought that the dopamine is oxidized by the phenol oxidase to produce a quinone. The quinone is thought to cross-link the structural proteins to form a strong, inert exoskeleton, the perisarc. Attempts to demonstrate peroxidase using benzidine methods are also described. Both the spherical inclusions of the tanning cells and the perisarc of the hydrothecae give a reaction with benzidine in the absence of hydrogen peroxide. This suggests the presence of an oxidizing agent which is not a peroxidase but is possibly a quinone.  相似文献   

13.
The cytoplasmic volume of wheat streak mosaic virus-infected cells was significantly greater than that of cells in healthy control tissue. Ultrastructural examination revealed that mainly cellular membranes and ribosomes filled the expanded cytoplasm. Imperfectly spherical inclusions, containing continuous endoplasmic reticulum membranes at the periphery and a mixture of membranes and ribosomes in the centre, were observed near nuclei at early infection stages. The inclusions became larger as infection progressed. Membranes and ribosomes proliferated also throughout the cell, forming a matrix in which organelles and various cytopathic structures were enclosed. Numerous vesicles were observed in the cytoplasm of other WSMV-infected cells. Multi-layered membrane bodies were found at later infection stages. Virus particles were present in the central space of these myelin-like structures. The presence of apparently intermediate stages in myelin-like structure development in chloroplasts suggest that at least some of the myelin-like structures originated from the chloroplasts.  相似文献   

14.
Different populations of metal-loaded and uncontaminated Porcelio scaber Latreille were studied. Combined light and electron microscopial methods as well as X-ray microanalysis were applied for localization and characterization of intracellular sites of metal deposition within the small cells of hepatopancreas. By means of cytochemistry and X-ray microanalysis it was shown that membrane-limited vesicles are important sites of deposition for lead, copper, zinc and probably smaller amounts of cadmium. The vesicles also contained phosphorus. They are identical with the reported cuprosomes and belong to the lysosomal system. In addition, considerable amounts of lead, copper, and cadmium were found in small structures outside of membrane-limited organelles.Abbreviations EDX energy-dispersive X-ray - P. scaber Porcellio scaber - STEM scanning transmission electron microscope - TEM transmission electron microscope - v volume - wt weight  相似文献   

15.
Electron optic study of inflammation infiltrating cells in juvenile periodontopathic tissue showed the presence of "nuclear-body"-type structures and of nuclear and cytoplasmic virus-like inclusions, which predominated in cells presenting degenerative modifications commonly encountered in malignant cells. Their significance is discussed.  相似文献   

16.
The localisation of absorbed copper in the brown seaweeds Fucus vesiculosus L. and Fucus serratus L. was studied by X-ray microanalysis in the electron microscope. The metal was localised in the physodes of the photosynthetic and inner non-photosyn-thetic cells. No significant copper was found in the cell walls of these algae, which had been collected from sites which were continually polluted by run-off from old copper mines.  相似文献   

17.
High concentrations of copper were demonstrated histochemically in the enterocytes lining the ileum and distal jejunum of suckling rats. Copper was not detected in cells from the duodenum or proximal jejunum of these rats or from any region of the small intestine of rats in which "closure" had taken place. X-Ray microanalysis demonstrated copper, in equi-atomic association with sulphur, within discrete vesicles in the supranuclear cytoplasm of the enterocytes. Despite the high concentrations of these two elements no biochemical evidence was found for the presence of significant amounts of copper-binding metallothionein. The highest concentrations of copper (226 +/- 48 mg atoms/kg dry wt: +/- SD) were found in vesicles adjacent to the nucleus, which did not accumulate particulate tracers, or calcium from the lumen of the intestine. These vesicles probably result from the coalescence of Golgi-derived primary lysosomes followed by fusion with endocytic vacuoles. They may provide a mechanism of copper excretion from the neonatal rat.  相似文献   

18.
Liver obtained from copper-intoxicated rats was studied by electron microscopy and electron probe microanalysis. Large ultrastructural disorders in liver cells appeared at the level of lysosomes and mitochondria. Diffuse and aggregate copper granules were observed in the entire cell, but mainly in pericentrolobular and periportal zones. Probe analysis revealed an increased copper deposit, particularly during the chronic copper intoxication, and a very high concentration of iron gradually accumulated.  相似文献   

19.
A study of the fine structure of the avian lung revealed the presence of a unique laminated membrane surface and associated osmiophilic inclusions in epithelial cells of the tertiary bronchi and atria. These structures were not found in the air-capillary epithelium. Each lamination of the membrane surface had the appearance and dimensions of the unit membrane. It is suggested that the laminated membrane surface is associated with the formation of the osmiophilic inclusions and that these inclusions compare with those described in mammalian alveolar epithelium. It is further suggested that the laminated membrane surface is lipoprotein or phospholipid in composition and is responsible for the surface-tension-reducing properties of avian lung extracts.  相似文献   

20.
Synthesis of water-soluble copper-containing sulfates of arabinogalactan was carried out for the first time by the ion exchange method. Their composition and structure were studied by the methods of elemental and chemical analysis, X-ray spectral microanalysis, atomic force microscopy (AFM), infrared spectroscopy (FTIR), and electron paramagnetic resonance (EPR). According to the AFM data, the surface of copper-containing polymer films does not have inclusions and consists of homogeneous crystallites of a spherical and slightly elongated shape and transverse dimensions of about 100 nm. The composition of copper- containing polymers was studied by the chemical method and X-ray spectral microanalysis. The absence of nitrogen in the obtained polymer indicates the complete replacement of ammonium cations in the ammonium salt of AG sulfate with the copper cations. The IR spectrum of copper-containing AG sulfate is similar to that of the sodium salt of sulfated arabinogalactan. Superposition of two signals was observed in the EPR spectrum of copper-containing AG sulfate. One of them belongs to isolated Cu2+ ions; another, to associated Cu2+ ions in the salt-like compounds. The integral intensity of isolated Cu2+ ion signals (anisotropic signal) and associated ions (isotropic signal) depends on the copper content in the polymer. Water-soluble coppercontaining polymers of AG sulfates have prospects for their use in medicine.  相似文献   

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