scholarly journals Pathogenesis of Digestive Tract Lesions in Duck Plague

1975 ◽  
Vol 12 (5-6) ◽  
pp. 349-361 ◽  
Author(s):  
S. J. Proctor

White Pekin ducklings were inoculated orally with duck plague virus. Tissues from the digestive tract were collected daily after inoculation and examined by light, electron and fluorescent microscopy. There were necrosis and degeneration of stratified squamous epithelium of the esophagus and cloaca, epithelium of intestinal crypt and esophageal submucosal glands, macrophages in the lamina propria, and submucosal fibrocytes and lymphocytes. Submucosal hemorrhages occurred after degeneration and necrosis of lymphocytes, macrophages, fibrocytes and epithelial cells. Viral antigens were detected in all these cells by use of fluorescein-labeled antibodies. With the electron microscope, nucleocapsids were seen in the nuclei, budding through the inner nuclear membrane; enveloped virions were present in cytoplasmic vacuoles of macrophages, epithelial cells and fibrocytes. In lymphocytes, nucleocapsids were also in the nuclei, but karyorrhexis and cytolysis occurred before viral maturation was completed.

2015 ◽  
Vol 87 (2) ◽  
pp. 867-878 ◽  
Author(s):  
Marcella L. Dos Santos ◽  
Fábio P. Arantes ◽  
Kleber B. Santiago ◽  
José E. Dos Santos

The digestive tracts of 44 specimens of Schizodon knerii were studied using anatomical, histological and histochemical techniques. The mouth has terminal position, the lip epithelium is squamous stratified with mucous, claviform cells and taste buds, teeth have an incisive form and the tongue has a stratified squamous epithelium with mucous cells and taste buds. The oropharynx cavity is formed by gill apparatus and pharyngeal teeth. The oesophagus presented pleated mucosa, a stratified squamous epithelium with mucous cells, oesophageal glands and taste buds. The stomach presented cardiac, fundic and pyloric regions, simple prismatic epithelium with tubular glands, with none in the pyloric region. The intestine contains 11-15 pyloric caeca, a simple prismatic epithelium with brush border, goblet cells and lymphocytes. Mucosal cells, oesophageal glands and goblet cells reacted positively to PAS, amylase + PAS, Ab pH 2.5 and Ab pH 0.5. Gastric prismatic cells reacted positively to PAS, amylase + PAS, but only those in the pyloric region reacted positively to Ab pH 2.5 and Ab pH 0.5. The results improve the understanding of the anatomy of S. knerii feeding habits and the presence of mucosubstances in the epithelium, highlights the importance of glycoproteins for passing food through the digestive tract.


Development ◽  
1961 ◽  
Vol 9 (3) ◽  
pp. 370-384
Author(s):  
C. B. McLoughlin

It is well established that in the developing chick the underlying mesenchyme initiates the appearance of specific epidermal derivatives, e.g. feathers (Sengel, 1956), claws (Cairns & Saunders, 1954), and the preen gland (Gomot, 1958). On the other hand, it is not yet known to what extent the epidermis is independent of mesenchymal intervention for its basic differentiation into a stratified, squamous epithelium. Sobel's (1958) work on the 8-day chick pituitary suggests that the differentiation and multiplication of certain epithelial cells cannot proceed in the absence of mesenchymal elements. She found that the isolated epithelial cells of the hypophysial rudiment survived but were unable to differentiate or multiply; when associated with perichondrial fibroblasts, however, they resumed mitosis and produced typical α and β cells. In the first part of the present investigation, experiments were made to see whether the embryonic epidermis, like the hypophysial epithelium, requires the resence of fibroblasts to enable it to grow and differentiate, or whether it can proliferate, acquire its characteristic squamous structure and keratinize, when isolated and cultivated in the absence of connective tissue.


1988 ◽  
Vol 97 (4) ◽  
pp. 365-372 ◽  
Author(s):  
Gerd Artur Wild ◽  
Gabriele Wille ◽  
Dietmar Mischke

The epithelial lining of lateral cervical cysts (LCCs) was analyzed for keratin polypeptide composition by means of high resolution gel electrophoresis and immunoblotting using polyclonal rabbit antikeratin antisera of defined specificity. The keratin phenotype expressed in branchial mass epithelia was found to be homologous to the profiles obtained for the squamous epithelium of corresponding palatine tonsils, but was clearly different from related polypeptide complements of both epidermis and simple (columnar) epithelium. The presence of particular keratin members (pairs 5/14 and 4/13) strongly indicates that branchial mass inner lining derives from keratinocytes that are programmed to form a stratified squamous epithelium and reveal, at least biochemically, an upper digestive tract or esophageal type of differentiation. On the basis of these data and the recent finding that a neck lymph node is involved as a target tissue in LCC formation, hypotheses concerning branchial mass histogenesis in general appear to be highly unsettled. We propose an alternative model that may explain the conflicting clinical, anatomic, and morphologic findings associated with LCC disease.


2011 ◽  
Vol 49 (1) ◽  
pp. 107-111
Author(s):  
M. Laudien ◽  
S. Dressel ◽  
J. Harder ◽  
R. Glaser

OBJECTIVE: The intact nasal barrier is a prerequisite for a functioning defense of the upper airway system, in particular the permanent threat by inhaled potentially harmful microorganisms. Antimicrobial peptides (AMP) play an important role in maintaining barrier function. There is few data about AMP in respect of nasal mucosa. This study is addressed to gain further insight into the differential AMP expression and secretion pattern according to defined anatomical regions of the vestibulum nasi and turbinates. PATIENTS AND METHODS: ELISA was applied to quantify concentrations of AMP RNase-7, psoriasin, hBD-2, hBD-3 and LL-37 in nasal secretions of 20 healthy volunteers. Immunohistochemistry was used to detect the local cellular sources of AMP in the vestibulum nasi (squamous epithelium) and compared to the mucosa of the turbinates (pseudostratified epithelium) in 10 healthy volunteers. RESULTS: Expression of RNase 7 and psoriasin was detected in all nasal secretion specimens, whereas LL-37 was detected in 16, hBD-2 in 5 and hBD-3 in 6 specimens. In the vestibulum nasi, luminal cell layers were demonstrated as local cellular sources for hBD-3 and RNase 7, whereas psoriasin was found in all layers of the stratified squamous epithelium. LL-37 was detected in 1 stroma cells sample, whereas hBD-2 was not detected at all. In turbinate biopsie,s hBD-3 and LL-37 were detectable in the epithelium, stroma cells and submucosal glands. RNase 7 was only present in submucosal glands. HBD-2 and psoriasin were not detected. CONCLUSION: These data demonstrate that the nasal epithelium contains a chemical defense shield through the expression and secretion of various AMP.


1993 ◽  
Vol 78 (5) ◽  
pp. 821-825 ◽  
Author(s):  
Mark S. Ledoux ◽  
Ona M. Faye-Petersen ◽  
Patricia A. Aronin ◽  
Yoginder N. Vaid ◽  
R. Marshall Pitts

✓ The case of a combined intra- and extraspinal neurenteric cyst in an infant is reported. This case is unique because an intraspinal cyst was not suspected clinically until large numbers of squamous epithelial cells were obtained at lumbar puncture performed as part of a workup for a septic entity. The cyst extended from an intradural location ventral to the conus medullaris at L-1 through a ventrolateral defect in the S-4 vertebral body to communicate with a large presacral component. The entire cystic cavity was lined by stratified squamous epithelium. The possible pathogenesis of this lesion is discussed.


2021 ◽  
Author(s):  
Yutong Yan ◽  
Mingzhen Fan ◽  
Kunyuan Zhu ◽  
Yuyang Miao ◽  
Xiaoe Zhao ◽  
...  

Abstract Background: The antimicrobial peptide (AMP) S100A7, with antimicrobial activities for a broad spectrum of bacteria, have attracted more and more attention for the prevention and treatment of mastitis. However, in goat mastitis, there is little information about the expression and regulation mechanism of S100A7. In present study, the immunolocalization of S100A7 in healthy and mastitis goat udder were compared. In order to further explore the regulatory mechanism of S100A7 expression in mammary epithelial cells (MECs), goat MECs were isolated and treated by 2.5, 5, 10 and 20 μg/mL lipopolysaccharide (LPS) respectively for different time.Results: Both in healthy and mastitis goat teat, S100A7 was mainly expressed in stratified squamous epithelium of teat skin and streak canal. In healthy goat mammary gland, weakly S100A7 immunoreactivity was present in the alveolus. But in the collapsed alveolus of mastitis goat mammary gland, densely S100A7 immunoreactivity could be observed.The goat MECs were treated by 2.5, 5, 10 and 20 μg/mL LPS respectively for different time. For all of these four groups, after treatment for 3 h, increase in S100A7 mRNA expression and protein secretion were detected compared to control (p<0.05). For 10 and 20μg/mL LPS groups, after treatment for 6 h, the mRNA and secreted protein levels of S100A7 were remarkably up-regulated compared to control(p<0.01). For all of these four groups, the secretion level of S100A7 descended after 48 h treatment. Moreover, after treatment with LPS, the mRNA levels of Toll-like receptor 4(TLR4) and MyD88 were up-regulated, and the phosphorylation of p65 was up-regulated markedly compared to control. However, adding TLR4 inhibitor TAK-242 or/and NF-κB inhibitor QNZ significantly suppressed the phosphorylation of p-65,and then inhibited the expression and secretion of S100A7 induced by LPS treatment.Conclusions: S100A7 was mainly expressed in stratified squamous epithelium of teat skin and streak canal. In mastitis goat mammary gland alveolus, the expression level of S100A7 was up-regulated compared to that in healthy goat. LPS induced the expression and secretion of S100A7 in goat MECs depended on concentration and treatment duration. Moreover, LPS induced the expression and secretion of S100A7 in goat MECs via TLR4/NF-κB signaling pathway.


1988 ◽  
Vol 2 (2) ◽  
pp. 240-244
Author(s):  
K. Uobe ◽  
S. Wada ◽  
M. Wato ◽  
T. Nishikawa ◽  
A. Tanaka ◽  
...  

The aim of this study was to produce and characterize monoclonal antibodies against human gingival epithelial cells and gingival fibroblasts. By using these whole cells as immunogens, we were able to generate a large number of monoclonal antibodies reacting with tissue antigens, in particular antibodies that reacted with desmosomes (MoAbs 7 and 8) and basement membrane (MoAb FB-1) antigens. MoAbs 7 and 8 produced from epithelial cells stained cell membranes of epithelium and desmosomes, respectively, as shown by light and immunoelectron microscopy. The epitopes to which MoAbs 7 and 8 were reactive were stable against various treatments; only periodate oxidation abolished the tissue reactions with MoAb 8. Extraction of gingiva with SDS or NP-40, SDS-PAGE analysis, and Western blotting showed that the MoAb 8 identified an antigen with a molecular weight of 100,000 daltons. MoAb FB-1 produced from fibroblasts immunolabeled the basement membranes. The FB-1 antigen was clearly different from any of the known ubiquitous basement membrane components, such as type IV collagen, laminin, and fibronectin. Examination of the distribution and localization of the antigen showed that it was present in the basement membrane beneath stratified squamous epithelium. FB-1 did not react with any of types I-VI collagens in ELISA, but immunoelectron microscopy showed that the antigen reacting with FB-1 was present in the lamina fibroreticularis of the basement membrane and was comprised of collagen-like fibers. These results suggest the possible existence of a new collagen other than types I-VI in the basement membrane beneath stratified squamous epithelium.


2000 ◽  
Vol 37 (3) ◽  
pp. 268-271 ◽  
Author(s):  
A. Espinosa De los Monteros ◽  
J. Martín de las Mulas ◽  
A. Fernández ◽  
J. Orós ◽  
F. Rodríguez

A cutaneous melanocytoma-acanthoma in a 2-year-old female German Shepherd Dog was characterized by the presence of two populations of neoplastic cells: epithelial and melanocytic. The epithelial component consisted of nests of well-differentiated stratified squamous epithelium closely associated with neoplastic melanocytes. The epithelial cells immunoreacted with both monoclonal and polyclonal anti-cytokeratin antibodies, and immunoreaction to S-100 protein and vimentin was observed in the melanocytic cells. This rare pigmented skin neoplasm of the dog apparently has a benign behavior.


Author(s):  
Al W. Stinson

The stratified squamous epithelium which lines the ruminal compartment of the bovine stomach performs at least three important functions. (1) The upper keratinized layer forms a protective shield against the rough, fibrous, constantly moving ingesta. (2) It is an organ of absorption since a number of substances are absorbed directly through the epithelium. These include short chain fatty acids, potassium, sodium and chloride ions, water, and many others. (3) The cells of the deeper layers metabolize butyric acid and to a lesser extent propionic and acetic acids which are the fermentation products of rumen digestion. Because of the functional characteristics, this epithelium is important in the digestive process of ruminant species which convert large quantities of rough, fibrous feed into energy.Tissue used in this study was obtained by biopsy through a rumen fistula from clinically healthy, yearling holstein steers. The animals had been fed a typical diet of hay and grain and the ruminal papillae were fully developed. The tissue was immediately immersed in 1% osmium tetroxide buffered to a pH of 7.4 and fixed for 2 hrs. The tissue blocks were embedded in Vestapol-W, sectioned with a Porter-Blum microtome with glass knives and stained with lead hydroxide. The sections were studied with an RCA EMU 3F electron microscope.


Author(s):  
S. Mukherjee ◽  
T. Guha ◽  
B. Chakrabarti ◽  
P. Chakrabarti

The cervix is an important organ in reproduction. Its malfunction is frequently a factor for infertility. Ectocervix region does not appear to have received much attention although many studies have been reported on the endocervix. We report here our SEM observations on ectocervix in certain pathological conditions compared to normal ectocervix.Ectocervix specimens from human females with specific pathological disorders were processed for Scanning Electron Microscopy by conventional method and they were examined in a Philips SEM.The normal ectocervix is lined by flat layer of squamous epithelial cells with microridges (Fig. 1). These cells are known to be formed from columnar cells through metaplastic transformation. The cells of carcinoma-bearing ectocervix show a disorganised appearance (Fig. 2). In non-malignant tumour surface some cuboidal and few columnar cells were seen (Fig. 3). A cyst appears like an overgrowth on the surface of the squamous epithelium (Fig. 4). In ulcerated ectocervix a marked reduction of epithelial cells are observed (Fig. 5); the cells are devoid of microridges and, the large polygonal cells, as observed in normal tissues, have somehow acquired comparatively small hexagonal shape


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