China
Africa
Explore chapters and articles related to this topic
Organoid Technology for Basic Science and Biomedical Research
Published in Hyun Jung Kim, Biomimetic Microengineering, 2020
Szu-Hsien (Sam) Wu, Jihoon Kim, Bon-Kyoung Koo
The stomach contains two main anatomical parts: the corpus and antrum in humans, and the forestomach (rostral), corpus, and antrum (caudal) in mice. Unlike the protruding villus structures in the small intestine, the stomach contains invaginated glands in the corpus and antral parts. The gastric glands are divided into four anatomical segments (from top to bottom of the gland): the gastric pit, isthmus, neck, and base regions (Kim and Shivdasani 2016). Each part of the stomach gland contains different cell types which carry out specific functions, such as mucus-secreting pit cells, rapidly dividing cells in the isthmus region, mucus-secreting neck cells and terminally differentiated enzyme-secreting chief cells. In between these cells, hormone-secreting enteroendocrine cells are also found throughout the gland and parietal cells, which secrete hydrochloric acid, are abundant within the corpus glands.
Cryptosporidium Spp. in Lower Vertebrates
Published in J. P. Dubey, C. A. Speer, R. Fayer, Cryptosporidiosis of Man and Animals, 2018
In snakes, Cryptosporidium sp. has been reported to infect boids, colubrids, elapids, and viperids (Table 1), localizing in the gastric mucosa (Figure 1). Although oocysts may be passed in the feces for many months or even years,848 it is most often diagnosed because of a clinical problem. Clinical signs might include anorexia, persistent or intermittent postprandial regurgitation, lethargy, firm midbody swelling, and progressive weight loss. Positive-contrast gastrography and fluoroscopy have revealed narrowing of the gastric lumen, with circumferential swelling suggestive of a thickened stomach wall.282 Microscopic lesions consist of hyperplasia and hypertrophy of gastric glands, concomitant atrophy of the granular cells, edema of the submucosa and lamina propria, reduction in lumenal diameter, and inflammation of gastric mucosa.118,128,282,534,786 Mucosal petechiae, aggregations of lymphocytes and heterophils, exaggeration of longitudinal rugae, excess mucus production, and multifocal necrosis can result from infection.128,786 Secondary invasion of the mucosa with Gram-negative bacteria has been reported also.534 Adenovirus-like intranuclear inclusions occur in the glandular epithelium of some infected animals377a and suggests the possibility that a virus might predispose snakes to a more severe infection.
Fish, Amphibians, and Reptiles
Published in Ronald Fayer, Lihua Xiao, Cryptosporidium and Cryptosporidiosis, 2007
Clinical signs in snakes are associated with gastric hyperplasia of the mucus-secreting cells (Brown-stein et al., 1977). Snakes often have foul-smelling diarrhea and midbody swelling with reduction in lumen diameter; they can live from a few days up to 2 years after the appearance of clinical signs (Cranfield and Graczyk, 1995, 2000, 2006). Weight loss often occurs with persistent or periodical postprandial regurgitation 3 to 4 days after a meal. The gastric mucosa appears edematous with mucosal thickening and exaggerated longitudinal rugae that have copious amounts of mucus adhered to it. The surface may exhibit petechiae, enlarged rugae, excess mucous, and multiple foci of necrosis. Microscopy of gastric tissue reveals hyperplasia and hypertrophy of gastric glands, atrophy of granular cells, edema of the submucosa and lamina propria, and inflammation of the gastric mucosa characterized by infiltration with lymphocytes and heterophils.
Anti-ulcerogenic effect of methanol fraction of Ocimum gratissimum leaves extract and honey on indomethacin-induced gastric ulcer in rats
Published in Egyptian Journal of Basic and Applied Sciences, 2021
Aanuoluwa James Salemcity, Blessing Oluwagbamila Omolaso, Oghenefega Sheila Ogegere, Victoria Olasumbo Oluokun
The observed normal histological structures in all gland cells, gastric epithelial cells, parietal and the chief cells in stomach of the control group is a suggestion that there was no gastrocellular damage in the animals. The mild infiltration of the gastric glands, lamina propria and the severe infiltration by inflammatory cells in the submucosal layers of the untreated group indicated that indomethacin induced inflammation in the stomach. This is supported by the study that indomethacin is known to induce the reactive oxygen metabolites in animal models which may contribute to mucosal injury. The ability of MEF in dose-dependent manner as well as its combination with honey to prevent ulceration could suggest that the plant and honey contain some bioactive principles which were capable of impeding the onset of gastric ulcer, thus exhibiting a gastro-intestinal protective effects. This may be through preservation of mucosa membrane and stimulation of prostaglandin synthesis necessary for gastro-protection. Decreased prostaglandin level has been attributed to impaired gastro-protection and increased gastric secretion which are important events in the etiology of mucosal ulceration [47–49].