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1.
Four patients who had undergone abdominoperineal resection for carcinoma of the colon and who had been taking oral bismuth subgallate developed a stereotyped recurrent and reversible neurological syndrome. This was characterized by confusion, tremulousness, clumsiness, myoclonic jerks, and an inability to walk. All patients were extensively investigated and no cause could be found, but symptoms regressed when the intake of bismuth was stopped. Postmortem examination in one patient failed to show any appreciable abnormality apart from a loss of Purkinje cells in the cerebellum. In the other three patients amino-acid chromatography performed on urine showed the presence of an abnormal unidentified constituent. It is thought that these four patients developed an encephalopathy associated with their bismuth subgallate ingestion.  相似文献   

2.
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   

3.
Summary At the base of the optic tentacular ganglion there is a group of large monopolar cells containing numerous secretory inclusions. These are the collar cells. Secretory material can be seen accumulating in swollen portions of the granular endoplasmic reticulum. It is postulated that this material is transported to the Golgi bodies and thus the limiting membrane of the inclusions is derived from the Golgi membranes. The Golgi bodies appear to be polarized and small vesicles resembling secretory inclusions are associated with one face of these organelles. The secretory inclusions fuse together to form large membrane-bound secretory pools in the perikaryon. The collar-cell processes are packed with secretory inclusions. These processes traverse the digital extensions of the tentacular ganglion and pass into the epithelium covering the tip of the tentacle. The secretory inclusions do not resemble neurosecretory inclusions in other situations. The collar cell processes receive a nerve supply from single axons containing granular and agranular vesicles. The evidence that these cells may be modified neurons is only minimal.This work was supported by the Australian Research Grants Committee.  相似文献   

4.
Helicobacter pylori is a major human pathogen that can cause peptic ulcers and chronic gastritis. Bismuth-based triple or quadruple therapies are commonly recommended for the treatment of H. pylori infections. However, the molecular mechanisms underlying treatment with bismuth are currently not fully understood. We have conducted a detailed comparative proteomic analysis of H. pylori cells both before and after treatment with colloidal bismuth subcitrate (CBS). Eight proteins were found to be significantly upregulated or downregulated in the presence of CBS (20 μg mL−1). Bismuth-induced oxidative stress was confirmed by detecting higher levels of lipid hydroperoxide (approximately 1.8 times) and hemin (approximately 3.4 times), in whole cell extracts of bismuth-treated H. pylori cells, compared with those from untreated cells. The presence of bismuth also led to an approximately eightfold decrease in cellular protease activities. Using immobilized-bismuth affinity chromatography, we isolated and subsequently identified seven bismuth-binding proteins from H. pylori cell extracts. The intracellular levels of four of these proteins (HspA, HspB, NapA and TsaA) were influenced by the addition of CBS, which strongly suggests that they interact directly with bismuth. The other bismuth-interacting proteins identified were two enzymes (fumarase and the urease subunit UreB), and a translational factor (Ef-Tu). Our data suggest that the inhibition of proteases, modulation of cellular oxidative stress and interference with nickel homeostasis may be key processes underlying the molecular mechanism of bismuth’s actions against H. pylori. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

5.
OBJECTIVE: To describe the cytologic features of secretory meningioma on crush preparations. STUDY DESIGN: In five cases, the diagnosis of secretory meningioma was made and crush preparations were available. In each case, crush preparations were made at the time of intraoperative consultation from an open biopsy specimen or stereotactic biopsy. RESULTS: Hematoxylin and eosin-stained crushes showed the presence of clusters of cohesive cells containing variable numbers of inclusions among less cohesive typical meningothelial cells. In two cases, the inclusions were especially prominent. Inclusions varied in size from 3 to 40 microns, had a well-defined rim and contained finely granular or hyaline material and a central core. CONCLUSION: Secretory meningiomas demonstrate distinct cytologic features on crush preparations. Recognition of these inclusions is important since their prominence in some stereotactic smear preparations may lead to diagnostic problems.  相似文献   

6.
Bismuth complexes have been widely used in clinical treatment as antiulcer drugs. However, different adverse effects have been observed and the diagnosis is generally confirmed by the detection of bismuth in blood or blood plasma. In this study, binding of bismuth to human serum albumin was studied by fluorescence spectroscopy with the binding constant logK(a) to be 11.2. Competitive binding of bismuth to human albumin and transferrin was carried out at pH 7.4 by FPLC and ICP-MS. It was found that over 70% of bismuth binds to transferrin even in the presence of a large excess of albumin (albumin/transferrin=13:1) at pH 7.4, 10 mM bicarbonate. The distribution of bismuth between the two proteins was almost unchanged when Cys(34) of albumin was blocked. However, all bismuth binds to albumin when iron-saturated transferrin was used. Almost all of the bismuth was distributed over the fractions containing transferrin (70%) and albumin (<30%) in serum. The percentage of bismuth associated with transferrin was further increased by 15% with elevated transferrin in serum. Binding of bismuth to transferrin is much stronger than human albumin. Transferrin is probably the major target of bismuth in blood plasma, and it may play a role in the pharmacology of bismuth.  相似文献   

7.
Plastids were observed in all stages of laticifer differentiation in Papaver somniferum L. Plastids in laticifer initials were present as proplastids that later developed electron-dense inclusions, but never possessed the thylakoids or starch grains that characterize chloroplasts in other cells. Electron-dense inclusions in laticifer plastids were membrane-bound and appeared to arise from the accumulation of material within an invagination of the inner plastid membrane. Cytochemical studies of these plastid inclusions indicated that their matrix was not composed of crystalline protein, α-amylose, amylopectin or polysaccharide. The results suggest that the electron-dense, membrane-bound inclusions in laticifer plastids may be composed of lipoprotein.  相似文献   

8.
Ultrastructural study of the tissues of Veretillum cynomorium shows the presence of two mesenchymatous cellular states in the mesoglea: the nongranular mesenchymatous cells and the granular mesenchymatous cells. These latter possess, besides their cytoplasmic granules, some homogeneous fibrous inclusions, very similar to the fibrous material of the mesoglea. Granules and homogeneous fibrous inclusions are also present in the cytoplasm of some ectodermic and endodermic cells. These morphological results lead us to consider that mesoglea and epithelia can be occupied by the same granular cell type. Besides this, the digestive endodermic cells are sometimes very rich in heterogeneous fibrous inclusions histochemically identified as phagosomes. An autoradiographic study indicates two possible pathways for the synthesis of the mesoglea. The first involves the endoderm which elaborates the mesoglea at a fast rate but in small amounts. The second is due to the granular cells (mesenchymatous and epithelial) which show a slow rate of synthesis leading to the formation of the homogeneous fibrous inclusions. The heterogeneous fibrous inclusions of the digestive endodermic cell support the hypothesis of the involvement of these cells in mesogleal degradation.  相似文献   

9.
PurposeIn cerebral angiography, for diagnosis and interventional neuroradiology, cone-beam computed tomography (CBCT) scan is frequently performed for evaluating brain parenchyma, cerebral hemorrhage, and cerebral infarction. However, the patient’s eye lens is more frequently exposed to excessive doses in these scans than in the previous angiography and interventional neuroradiology (INR) procedures. Hence, radioprotection for the lenses is needed. This study selects the most suitable eye lens protection material for CBCT from among nine materials by evaluating the dose reduction rate and image quality.MethodsTo determine the dose reduction rate, the lens doses were measured using an anthropomorphic head phantom and a real-time dosimeter. For image quality assessment, the artifact index was calculated based on the pixel value and image noise within various regions of interest in a water phantom.ResultsThe protective materials exhibited dose reduction; however, streak artifacts were observed near the materials. The dose reduction rate and the degree of the artifact varied significantly depending on the protective material. The dose reduction rates were 14.6%, 14.2%, and 26.0% when bismuth shield: normal (bismuth shield in the shape of an eye mask), bismuth shield: separate (two separate bismuth shields), and lead goggles were used, respectively. The “separate” bismuth shield was found to be effective in dose reduction without lowering the image quality.ConclusionWe found that bismuth shields and lead goggles are suitable protective devices for the optimal reduction of lens doses.  相似文献   

10.
Bismuth - sulphur quantum dots can be silver enhanced by autometallography (AMG). In the present study, autometallographic silver enhanced bismuth-sulphur nanocrystals were isolated from unfixed cryo-sections of kidneys and livers of rats exposed to bismuth (Bi207) subnitrate. After being subjected to AMG all the organic material was removed by sonication and enzymatic digestion and the silver enhanced Bi-S quantum dots spun down by an ultracentrifuge and analyzed by scintillation. The analysis showed that the autometallographic technique traces approximately 94% of the total bismuth. This implies that the injected bismuth is ultimately captured in bismuth-sulphur quantum dots, i.e., that Bi-S nanocrystals are the end product of bismuth metabolism.  相似文献   

11.
Cytoplasmic inclusions surrounded by a bilayer membrane were seen in thin sections. negatively stained and freeze-fractured preparations of Shewanella putrefaciens. Cells harvested from the late exponential and early stationary phase showed a higher number of these vesicles than bacteria isolated from early exponential or late stationary phase. Chemical dyes for polyphosphate or poly-beta-hydroxybutyrate did not stain the material enclosed within these vesicles. Elemental analysis of the material indicated that the content was organic in nature and might be a protein. HPLC analysis of the material showed that it was probably not a carbon source, nor an electron acceptor used by S. putrefaciens.  相似文献   

12.
Morphology and ultrastructure of Halprowia arthritidis, strain SR-1 (HSR), isolated from the synovial fluid of a patient with Reiter's syndrome, was studied in the membranes of the yolk sacs of the developing chick embryos and the L-cell culture. In acridine orange staining for light and fluorescent microscopy there was revealed intracellular cytoplasmic inclusions containing HSR structures at various stages of its reproduction characteristic of halprowia (chlamydia). The direct immunofluorescent method demonstrated the presence of a characteristic HSR antigen not only in the developed inclusions, but also at the early stages of infection, when the morphological HSR structures could not be found by light microscopy. The ultrastructure of the HSR inclusions and forms in the cycle of development (of the initial and elementary bodies) of the SR-1 strain was typical of other halprowia. A peculiar structure of a complex of cell wall and cytoplasmic membrane of the elementary body was described. Taking into consideration the biological characteristics of HSR revealed earlier it can be considered to be a typical representative of Halprowiales s. Chlamydiales. The data obtained on other halprowia, pointing out the fact that criteria of compactness and diffuseness of inclusions, the presence of absence of glycogen in the inclusions could not serve as taxonomic signs in classification of halrpowia, were confirmed on a model of the SR-1 studied.  相似文献   

13.
Cytoplasmic inclusions of various types of cells have been investigated by macerating or smearing and fixing and staining by different mitochondrial methods of technic. The results obtained as regards granular, rod-like, filamentous and globular forms immediately suggest a relation between these and similar cell inclusions which have in the past been described as mitochondria in certain cases of this material. While mechanical disturbance and drying before fixation apparently do not alter the staining properties of these forms, alcohol produces somewhat variable results depending upon the kind of material being investigated. Results indicate the presence in these smears of numerous intracellular bacteria, readily misinterpreted as mitochondria. In addition, there occur in certain cells, both in smears and sections, inclusions of indeterminate nature.  相似文献   

14.
Objectives. The aim of this study was to compare the dissolution, bioavailability, and anti– Helicobacter pylori activity of bismuth subnitrate and colloidal bismuth subcitrate. This could, first, provide insights into the mechanism of action of bismuth and, second, help to develop optimal therapeutic strategies.
Methods. Solubility and aquated size of bismuth species were determined in human gastric juice, while absorption into blood and urinary excretion of bismuth was determined in volunteers. Activity against H. pylori was determined in vitro in the presence and absence of antibiotics, while H. pylori eradication was compared in vivo.
Results. Bismuth from colloidal bismuth subcitrate was at least 10% soluble and ultrafilterable and was absorbed in volunteers (>0.5%), whereas that from bismuth subnitrate was insoluble and not absorbed (<0.01%). Colloidal bismuth subcitrate was active against H. pylori (mean inhibitory concentration, ≤12.5 μg/ml), while bismuth subnitrate was inactive (>400 μg/ml); neither was synergistic with antibiotics. With in vivo triple therapy, bismuth subnitrate was as effective as colloidal bismuth subcitrate in eradicating H. pylori (74% and 70% eradicated, respectively).
Conclusions. Colloidal bismuth subcitrate, unlike bismuth subnitrate, is partially soluble, absorbed in humans, and directly toxic to H. pylori in vitro. Surprisingly, however, these preparations had similar efficacy in vivo against H. pylori within triple therapy, suggesting that bismuth compounds may also exhibit indirect antimicrobial effects. We propose that this is an effect on the gastric mucus layer. Nonabsorbable bismuth compounds should be preferentially considered in bismuth-based therapies against H. pylori , as they would minimize toxicity while maintaining efficacy.  相似文献   

15.
The histological hallmark feature of Huntington’s disease (HD) and other polyglutamine repeat diseases is the presence of intracellular inclusions. Much work has been devoted to trying to determine the relationship between inclusion formation and neuronal injury. However, little attention has been paid to the variability and characteristics of inclusions themselves. Here, we characterize the morphological and biochemical composition of inclusions in both a transgenic mouse model (R6/2 line) and an inducible cell culture model of HD (iPC12Q74). We identified several morphologically distinct kinds of inclusions in different locations (nuclei, cytoplasm and cellular processes). Ubiquitin colocalized completely with all of these inclusions in both the iPC12Q72 and R6/2 models. In the inclusions in iPC12Q74 cells, the 20S and 11S proteasome subunits colocalized variably, and the 19S subunit did not colocalize at all. In inclusions in R6/2 mouse neurons, the 20S subunit colocalized completely, but neither the 11S nor the 19S subunits colocalized at all. While the role of inclusions in the pathogenesis of HD continues to be debated, we suggest that the content and structure of inclusions vary considerably, not only from cell to cell but even within individual cells. Their role in the pathogenesis of HD is likely to depend on their location as well as their composition.  相似文献   

16.
Summary Fluorescence spectroscopy and electron microscopic techniques have been employed to investigate a class of glial cells that is characterized by the presence in their cytoplasm of large fluorescing inclusions that stain with paraldehyde-fuchsin or chrome-hematoxyline-alum. In the periventricular nucleus the cells have been identified as a population of astrocytes whose inclusions emit an orange-red fluorescence. In the arcuate nucleus there are, in addition to an overwhelming majority of such astrocytes, also some microglial cells with similar characteristics. The ability of the latter to emit any kind of fluorescence has not yet been established. The fluorescence maximum of these astrocytic inclusions was found to be at 640 nm when excited at 405 nm. The data obtained suggest that the fluorescence observed is due to the presence of porphyrins in the astrocytic inclusions. In the majority of our electron microscopic pictures the inclusions lack a bounding membrane. By contrast, neuronal lipofuscin has an outer membrane. In cryostat sections, the lipofuscin emits a yellow fluorescence when excited at 400–410 Onm.  相似文献   

17.
Protein inclusions are associated with a diverse group of human diseases ranging from localized neurological disorders through to systemic non-neuropathic diseases. Here, we present evidence that the formation of intranuclear inclusions is a key event in cataract formation involving altered gamma-crystallins that are un likely to adopt their native fold. In three different inherited murine cataracts involving this type of gamma-crystallin mutation, large inclusions containing the altered gamma-crystallins were found in the nuclei of the primary lens fibre cells. Their formation preceded not only the first gross morphological changes in the lens, but also the first signs of cataract. The inclusions contained filamentous material that could be stained with the amyloid-detecting dye, Congo red. In vitro, recombinant mutant gammaB-crystallin readily formed amyloid fibrils under physiological buffer conditions, unlike wild-type protein. These data suggest that this type of cataract is caused by a mechanism involving the nuclear targeting and deposition of amyloid-like inclusions. The mutant gamma-crystallins initially disrupt nuclear function, but then this progresses to a full cataract phenotype.  相似文献   

18.
1. The ATPase activity in the spike-stalk cells of wheat was obviously localized at plasmallemma and the surface of cell wall bordering the intercellular spaces and their inclusions. The reactions of ATPase activity at chromatin and nucleoli were usually insignificant, and they were not found in vacuoles and other organelles (Figs. 1, 2, 3, 5, 6 and 7). 2. Three significant differences were observed between the middle part and the basal and upper part of the spike-stalk in wheat. (1) A large amount of inclusions were shown in the intercellular spaces of the middle part, and the high ATPase activity was seen at these inclusions (Figs. 6 and 7), but both they were seldom to be found in the intercellular spaces of the basal and upper part (Figs. 2 and 3). (2) The plasmodesmata of the middle part ceils was more than that of the basal and upper part ones (Figs. 1, 3 and 5). (3) In the middle part cells of spike-stalk, the cytoplasmic material was vigorously and actively transferred through the wall pores, and at the same time, the high ATPase activity was exhibited on the transferred cytoplasm (Figs. 4, 8 and 9). In addition, it was also observed that the cytoplasmic material entered into intercellular spaces from adjacent cells (Fig. 6). But it was hardly to see this phenomenon in the basal and upper part of spike-stalk. 3. It was discussed that the ATPase activity and the passage for material transport may play the role in transferring materials into the spike and they might be related to the development of the wheat spikelets.  相似文献   

19.
An ultrastructural study of the corneal fibrous tissue was performed in a case of Scheie's syndrome. Mucopolysaccharidosis deposits in keratocytes were observed as electron-clear and electron-dense inclusions. Modifications of the extracellular space included modifications of lamellar collagen organization and local hypertrophy of collagen bundles; presence of microfibrillar dense material isolating large irregular collagen fibers; and presence of fibrous long spacing type collagen fibers. The significance of these changes is discussed. This special form of collagen organization is supposed to appear in a modified microenvironment, that is the presence of an abnormal concentration of proteoglycans.  相似文献   

20.
Trypan blue has proved effective for demonstrating the presence of certain plant viruses within infected tissues. The amorphous and crystalline inclusions which constitute cytological evidence of viruses stain proportionately. The effects produced by different viruses react differently to the stain and those inclusions which do not absorb trypan blue tend to stain with phloxine. This selective staining is the basis for using trypan blue singly and in combination with phloxine as standardized procedures for demonstrating and differentiating cytological evidence of plant viruses. These tests are very rapid and are especially applicable to temporary mounts of living tissue but permanent mounts can be made from material fixed in formalin.  相似文献   

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