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1.
Ultrastructural features of Langerhans cells (LCs) of equine "Kasen" were studied. Electron microscopic observation revealed that LCs were dendritic and had irregular nuclear membranes. A number of Birbeck granules (Bgs) of various types were observed in the cytoplasm of LCs. In LCs in the upper stratum spinous, many Bgs were observed (Type 2 LC). LCs in the epidermo-dermal junction (EDJ) had a few Bgs, vesicles (multivesicular bodies) and highly electron-dense granular endosomes in the cytoplasm (Type 3 LC). Inactive LCs were also observed between the keratinocytes (Type 1 LC). Various types of LCs observed in the skin lesions of equine "Kasen" were interpreted as representing those that recognize, intake and process antigens.  相似文献   

2.
An immunohistochemical study was carried out on the kinetics of Langerhans cells (LCs) at various pathological stages of "Kasen". Skin lesions of "Kasen" that were collected by biopsy from May to October were classified histopathologically into three stages: initial (Group I, 31 cases), developing (Group II, 50 cases) and regressing (Group III, 13 cases). LCs showed a positive reaction with anti-equine thymocytes (EqT6) monoclonal antibody (MoAb) and anti-major histocompatibility complex (MHC) class II MoAb by immunohistochemical staining. The anti-EqT6 MoAb was intensely positive along the cytoplasmic process. The number of LCs per unit area increased markedly with the passage of time from the initial to the developing stage of the disease, particularly in the epidermo-dermal junction (EDJ). However, the number of LCs tended to decrease in the epidermal layer. In conclusion, the LCs moving into the epidermal layer moved into the EDJ and dermis during the time course of lesion development, and the changes occurring in LCs possibly influenced the progression of the skin lesions of "Kasen".  相似文献   

3.
The taste buds of bovine fungiform papillae were studied by light and electron microscopy using both histological and immunohistochemical methods. The taste buds existed in the epithelium of the apical region of the papillae. By electron microscopy, two types of taste cells, namely type I and type II cells, could be classified according to the presence of dense-cored vesicles, the cytoplasmic density and the cell shape. Type I cells were thin, had an electron-dense cytoplasm containing dense-cored vesicles, and possessed long thick apical processes in the taste pore. Type II cells were thick, had an electron-lucent cytoplasm containing many electron-lucent vesicles, rather than dense-cored vesicles, and possessed microvilli in the taste pore. Immunohistochemical staining with an antiserum against gustducin was investigated by both light and electron microscopy using the avidin-biotin complex (ABC) method. Some, but not all, of the type II cells exhibited gustducin immunoreactivity, whereas none of the type I cells showed any immunoreactivity.  相似文献   

4.
A 9-year-old horse had numerous firm, painless nodules of the skin and subcutis. Moderately vascular granulation tissue with numerous uni- or multinuclear reticuloendothelial cells was in the nodules and the regional lymph nodes but not in the viscera. By using special stains and electron microscopy, widespread amyloid deposits, mainly in the cytoplasm of reticuloendothelial cells, were identified. Amyloid was probably produced within the reticuloendothelial cells, then expelled from the dying cell and deposited in the intercellular space.  相似文献   

5.
Emperipolesis of hematopoietic cells within megakaryocytes was found in rats. The incidence was less than 0.3% in young rats (2 to 12 months old) but increased to 2-5% among the aging rats (18 to 24 months old). The incidence increased markedly in hyperplastic bone marrow secondary to chronic suppurative or neoplastic lesions. Mature neutrophils appeared to be the most common marrow cell engulfed by megakaryocytes. By light microscopy, engulfed cells were separated from megakaryocyte cytoplasm by a narrow pericellular space. By electron microscopy, marrow cells engulfed by megakaryocytes were located in the open canalicular system. Cell membranes of both engulfed cells and megakaryocytes were intact, and there was no fusion of cell membranes or phagosome formation in the megakaryocytes.  相似文献   

6.
Turkey herpesvirus (HVT) and an attenuated Marek's disease virus (MDV) replicated in organ cultures of chick embryo skin as assessed by immunofluorescence and/or electron microscopy. HVT-specific immunofluorescent antigen was detected in the feather follicle epithelium (FFE) and in the surface layer of the skin epidermis. Electron microscopy of infected explants revealed herpes-type cytopathology. Immature particles of both viruses appeared first in the nucleus. Oval or horseshoe-shaped non-enveloped particles of HVT and enveloped virions of MDV were seen in the cytoplasm of some transitional cells. The difference in the ability of HVT and MDV to form an envelope was believed to account for the difference in their transmissibility in chickens. The results indicated that HVT replicated in the FFE and in the epidermis of the skin. However, attempts to localise the site(s) of MDV replication by electron microscopy were unsuccessful.  相似文献   

7.
Recent investigations were conducted on mitochondria obtained from broilers with low and high feed efficiency (FE) within the same genetic line that were fed the same diet, thereby allowing relationships between mitochondrial function and the phenotypic expression of FE to be clearly established. In these studies, breast muscle, liver and duodenal mitochondria obtained from broilers with high FE exhibited a more tightly coupled respiratory chain along with lower electron leak and reactive oxygen species (ROS) production compared with broilers with low FE. Elevated electron leak in low FE was due to site-specific defects in electron transport at Complex I, III, or both of the respiratory chains in breast and leg muscles and at Complex I, II, or III (depending on energy substrate) in duodenal mitochondria. Increased ROS production was presumably responsible for increased protein oxidation in low FE muscle mitochondria. Of 14 respiratory chain proteins investigated in breast muscle, the expression of 4 (3 in Complex III and 1 in Complex IV) was higher in low FE mitochondria. Interestingly, low FE was associated with a general suppression in respiratory chain complex activities (I, II, III, and IV) in breast muscle and liver. Elucidation of the mechanisms responsible for lower ROS production and tighter coupling of the respiratory chain in high FE mitochondria will greatly facilitate our understanding of the cellular basis for the phenotypic expression of FE.  相似文献   

8.
Schizonts in the liver of 2 cats with cytauxzoonosis were studied by both light and electron microscopies. By light microscopy, the cytoplasm of macrophages in the sinusoids and small vascular channels contained schizonts with cytomeres or both cytomeres and mature merozoites. By electron microscopy, it was determined that schizogony occurred in 4 stages. The earliest stage was the presence of a multilobed structure containing finely granular protoplasm in the cytoplasm of the macrophage. The 2nd stage was an increase in height and number of the lobulations on the surface of the schizont. The 3rd stage involved the development of cytomeres and the appearance of a polar ring and rhoptries in everted sacculations on the cytomere membrane. Nuclei and mitochondria were incorporated into the sacculations before the release of mature merozoites into the host cell cytoplasm. In the last stage of schizogony, following massive merozoite formation and reduction in size of the schizont, residual nuclei divided by multiple fission. Each nuclear division became incorporated into a developing merozoite having preformed rhoptries, mitochondria, and a polar ring.  相似文献   

9.
Langerhans cells in porcine skin   总被引：1，自引：0，他引：1  
Langerhans cells (LCs) are resident dendritic cells (DCs) of skin and mucosal epithelium. The standard for identifying skin DCs as LCs is expression of langerin (CD207), a surface protein that mediates Birbeck granule (BG) formation upon internalization. Reports of BGs in porcine skin DC are contradictory, due to lack of langerin detection. Here, we present the sequence of porcine langerin/CD207, showing that the predicted porcine protein shares 75%/86% amino acid identity/similarity with human. Langerin mRNA was detected in porcine skin DCs by PCR and langerin protein was detected in both isolated skin DCs and skin sections by immunostaining. Approximately, 50-70% of skin DCs expressed langerin, demonstrating that the majority of porcine skin DCs are LCs. The full length sequence combined with the identification of antibodies reactive with porcine langerin, facilitates the study of LCs in swine, and advances the use of swine for studying skin diseases and infectious disease processes involving skin.  相似文献   

10.
Of 68 fecal samples from calves with diarrhoea which were tested for rotavirus with the latex agglutination test "Slidex Rota-Kit2" and by electron microscopy 33 samples were positive and 33 were negative with both tests respectively. Divergent results (latex test positive/EM negative and vice versa) were observed in one specimen only, respectively. Cross reactions with other viruses diagnosed by electron microscopy were not observed with the latex agglutination test. The "Slidex Rota-Kit2" is another suitable test for the diagnostic laboratory as well as for the veterinary practitioner for the detection of rotavirus in fecal samples of calves.  相似文献   

11.
Cutaneous inverted papillomas in dogs   总被引：1，自引：0，他引：1  
Inverted papillomas of the skin occurred in five dogs. Lesions were 1-2 cm, circumscribed, flask-like structures below the level of the surrounding normal skin. Walls of the structures consisted of hyperplastic epidermis, forming thin papillary projections on thin fibrovascular stalks. Cells in the stratum granulosum had clear cytoplasm, numerous keratohyalin-like granules of various sizes, and poorly defined intranuclear inclusions. These cells stained positively for papillomavirus group-specific antigens by both the peroxidase-antiperoxidase and avidin-biotin methods. Virions with a mean diameter of 35.7 nm were present within nuclei in cells of the stratum granulosum when examined by electron microscopy. In situ DNA hybridization, using a canine oral papillomavirus probe, localized papillomavirus DNA in canine oral papillomas, but not in canine cutaneous squamous or inverted papillomas, suggesting that a different papillomavirus type was present in the latter lesions. Although these lesions resembled intracutaneous cornifying epitheliomas (keratoacanthomas), they appear to be a distinct lesion, probably with a different etiology.  相似文献   

12.
犬瘟热的微生物学诊断研究   总被引：13，自引：1，他引：12  
对临床诊断为犬瘟热的１４例病犬，取其脑组织，运用细胞培养、合胞体检查、包涵体检查、免疫荧光试验、电镜观察等５种检测方法，就犬瘟热的微生物学诊断进行了系统的研究。结果表明，犬脑组织块与猫胚（ＦＥ）细胞或非洲绿猴肾（Ｖｅｒｏ）细胞共同培养，盲传的培养物出现不稳定的细胞病变，通过对不同代次的培养物检查包涵体，并作超薄切片或负染，电镜观察犬瘟热病毒（ＣＤＶ）粒子，证实分离到ＣＤＶ野毒。病犬脑组织切片经ＨＥ染色检查包涵体及用ＣＤＶ荧光抗体直接法检测脑抹片及接种犬脑的细胞培养物，均获得一定的阳性结果。建立的改良离子捕获电镜法，用于检测犬脑匀浆和犬脑接种细胞培养物，与离子捕获电镜法、免疫电镜法及直接电镜法相比，效果更为理想。１４例临床诊断为犬瘟热的病犬，综合运用上述微生物学手段检测，结果为１２例阳性，２例疑似。  相似文献   

13.
To accumulate histological information of cetaceans and basic information about metabolic systems of marine mammals, the thyroid gland of Risso's dolphins was examined by gross anatomical and light and electron microscopic observations. Gross anatomically, right and left lobes of the thyroid were not clearly discriminated, and no isthmus was observed. By light microscopy, irregular or oval follicular lumens were seen, and surrounded by follicular epithelial cells. By electron microscopy, the rough endoplasmic reticulum (rER) was seen adjacently to mitochondria at the basal and lateral regions of the follicular epithelial cells. RERs at the basal side of the cells sometimes contained flocculent material with the same electron density as the follicular lumen component. Microvilli were poorly developed at the apical surface of the cells. In the apical regions of the cells, there were typical Golgi complexes, multivesicular bodies, and granules with various size and electron density. The parafollicular cells were recognized among the follicular epithelial cells and in the interstitial regions but never protruded into the follicular lumen. These cells were present singly and/or formed clusters among the follicular epithelial cells, and often located adjacent to capillaries. They were obviously discriminated from follicular epithelial cells by higher electron density of their granules. In their cytoplasm, well-developed rERs, primary lysosomes, secondary lysosomes, multivesicular bodies, and phagosomes were recognized.  相似文献   

14.
Granulomatous lymphadenopathy, associated with the presence of needle-like refractile particles, was recognised in two dogs. The material was detected in macrophages, either free within the cytoplasm or in membrane-bound lysosomes. By mineral analysis under direct vision in an electron microscope microanalyser (EMMA 4) the particles were found to contain aluminosilicate.  相似文献   

15.
Ligated ileal loops of calves were inoculated with live and heat-killed Mycobacterium paratuberculosis and were examined by light and electron microscopy. At 5 hours after inoculation, acid-fast bacilli were in subepithelial macrophages, but not in M cells covering domes. At 20 hours, more than 50 acid-fast bacilli per cross section were in subepithelial macrophages in domes. Both living and heat-killed bacilli passed into domes. Addition of anti-M. paratuberculosis bovine serum to the inoculum enhanced entry of bacteria into domes. By electron microscopy, intact bacilli with electron-transparent zones (peribacillary spaces) were in the supranuclear cytoplasm of M cells at 20 hours. M cells also contained vacuoles, including electron-dense material interpreted as degraded bacilli. Subepithelial and intraepithelial macrophages contained bacilli and degraded bacterial material in phagosomes. These results suggest that calf ileal M cells take up bacilli, and that subepithelial and intraepithelial macrophages secondarily accept bacilli or bacterial debris which are expelled from M cells.  相似文献   

16.
Rhabdoid tumor is a highly aggressive neoplasm of unknown cellular origin in humans, usually occurring in the kidney and central nervous system of infants or children. In older patients, it occurs rarely in other organs, including the skin and soft tissues. A subcutaneous mass in a 13-year-old male mixed-breed cat was composed of nests or sheets of round to polygonal cells with glassy eosinophilic cytoplasmic inclusions. Immunohistochemically, many neoplastic cells expressed vimentin, localized to the cytoplasmic inclusions, whereas the cytoplasm of some neoplastic cells was diffusely positive for neuron-specific enolase, neurofilament, or S-100 protein. By electron microscopy, the cytoplasmic inclusions were found to be composed of aggregates of intermediate filaments. These findings are quite similar to the histologic, immunohistochemical, and ultrastructural features of human rhabdoid tumors and the few rhabdoid tumors reported in animals.  相似文献   

17.
Microvascular changes in the mammary gland in mice during pregnancy and lactation were investigated by scanning electron microscopy (SEM) with a corrosion cast method, transmission electron microscopy (TEM) and morphometry. By SEM, duct-associated capillary plexuses were sparsely distributed to branch into adipocytes during virgin period. With advance in pregnancy, both branches from the capillary plexuses and branches from the vessels surrounding adipocytes extended further to form capillary networks. The basket-like architecture was completed by day 18 of pregnancy. These findings may indicate that angiogenesis occurs frequently during this period. During lactation, the basket-like architecture still remained and the capillaries surrounding alveoli meandered. After weaning, the regression of microvasculature followed the degeneration of alveoli. By TEM and morphometry, the density of pinocytotic vesicles (PVs) (number of PVs per microns 2 of endothelium cytoplasm) increased twofold from day 18 of pregnancy to day 5 of lactation, furthermore increased threefold from days 10 to 20 of lactation, and subsequently decreased after weaning. Marginal folds and microvillous processes gradually increased in length with advance in pregnancy, reached the maximum from days 5 to 15 of lactation, and thereafter decreased. In addition, the capillaries with thinner walls were in close contact with alveoli during the late stage of pregnancy and during lactation. Furthermore, the alveolar epithelial cells had well-developed basal infoldings during lactation. These findings suggest that the capillaries play an important role in transporting materials necessary for milk production.  相似文献   

18.
Archival specimens of gastric mucosa of 10 raccoons (Procyon lotor), 9 porcupines (Erethizon dorsatum), 6 grey foxes (Urocyon cinereoargenteus), 6 bobcats (Lynx rufus), 4 skunks (Mephitis mephitis), and 3 black bears (Ursus americanus) were microscopically examined for evidence of Helicobacter-like organisms. Such organisms were seen in the specimens from the grey foxes and bobcats only. Histochemical stains (modified Steiner and carbol fuchsin methods) revealed long spiral organisms within lumina of gastric glands; however, neither gross nor microscopic lesions were observed. By electron microscopy (EM), the organisms were found to be free in the glandular lumina and were seen occasionally in the cytoplasm of gastric epithelial cells. Morphologically, 2 different phenotypes of spiral organisms were identified by EM. The organisms associated with bobcats appeared to be more tightly coiled than those seen in grey foxes. The presence of Helicobacter-like organisms in the gastric mucosa of grey foxes has not previously been described.  相似文献   

19.
牛病毒性腹泻病毒侵染宿主细胞的电镜观察   总被引：6，自引：0，他引：6  
用电镜观察了牛病毒性腹泻病毒Oregon C24株在侵染新生犊牛睾丸细胞中的形态发生。成熟的病毒颗粒呈直径约为50nm的球形颗粒，内含直径约为30nm的核芯。病毒侵染宿主细胞后，在胞质内复制，通过糙面内质网膜出芽成熟，病毒可通过侵染细胞外排或在细胞死亡后含有病毒颗粒的空泡破溃而释放到胞外。  相似文献   

20.
对霉形体进入DK传代细胞内,并进行增殖的情况,作了详细的电镜观察.结果如下:(1)霉形体靠近传代细胞膜表面呈串珠样排列;霉形体与传代细胞膜表面接触部位融合增厚,电子密度增高,向内凹陷,将霉形体裹入细胞质,形成由膜结构包着的包涵体.(2)在传代细胞质中,除可见由膜结构包裹着的霉形体性包涵体外,还可见没有任何膜包着的散在的霉形体,并且均可见到霉形体的裂殖增殖相和出芽增殖相.(3)在传代细胞核的核周池和核质中,均见到典型的霉形体及其裂殖增殖相.(4)霉形体在传代细胞中大量的增殖,致使细胞崩解,霉形体即被释放出来.(5)霉形体使传代细胞出现严重的超微病变.本文还讨论了传代细胞培养污染霉形体后难以救治的根本原因是,霉形体在传代细胞内增殖,故仅仅着眼于消除培养液中的霉形体是不能达到预期结果的.  相似文献   

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