秦岭细鳞鲑消化系统的形态学观察

运用大体解剖和常规组织学方法对秦岭细鳞鲑消化系统的组织形态进行了系统观察。结果表明,秦岭细鳞鲑的消化道由口咽腔、食道、胃和肠等4部分组成,除口咽腔外,管壁由内向外分为黏膜、黏膜下层、肌层和浆膜。口咽腔宽大,上颌、犁骨及腭骨等处布有细齿,黏膜衬以复层扁平上皮,间有较多的黏液细胞和少量的杯状细胞及味蕾;食管粗而短,黏膜向管腔突出形成多个纵行皱襞,上皮由复层扁平上皮逐渐向单层柱状过渡,上皮细胞间可见到数量较多的粘液细胞和杯状细胞,食管腺不发达;胃体积较大,呈“U”形,包括贲门部、胃体和幽门部,胃体部小凹及胃底腺结构明显,肌层发达;胃与肠相接处有63-65个幽门盲囊,肠道粗短而略微盘曲,黏膜上皮为单层柱状,未见明显的肠腺。以上结果显示,秦岭细鳞鲑消化道组织结构与其肉食性功能密切相关。肝小叶界限不清;双列肝细胞围绕中央静脉呈放射状走行,肝细胞个体大、呈多边形,核呈圆形或卵圆形,1-2个。胰脏大部分环绕前肠边缘、呈细长条索状,另可见分散于幽门盲囊及胃周围的弥散部分;其外分泌部为管泡状腺,腺细胞呈锥体形,胰岛结构明显。     

Mesenteric and omental sclerosis associated with metastases from gastrointestinal neoplasia in the dog

Eleven cases of adenocarcinomas of the gastrointestinal tract were reviewed. Six tumours were considered to be of gastric origin, three originated from the jejunum and two from exocrine pancreatic tissue. Clinical signs were variable, but intermittent anorexia and vomiting were common features. Grossly, there was marked fibrosis involving the mesentery in nine cases, the omentum in 10 cases, and the abdominal surface of the diaphragm in three cases. Neoplasms that primarily involved the stomach or jejunum caused localised thickening of the bowel wall with mucosal ulceration. Pancreatic masses were continuous with the peritoneal lesion. The major histological feature in the mesentery and omentum was small islands of neoplastic cells surrounded by abundant proliferating connective tissue.     

Pancreatic metaplasia in the gastro-achlorhydria in WTC-dfk rat, a potassium channel Kcnq1 mutant

The WTC-deafness Kyoto (dfk) rat is a new mutant characterized by deafness and abnormal, imbalanced behavior. WTC-dfk rats carry an intragenic deletion at the Kcnq1 gene; KCNQ1 plays an important role in K(+) homeostasis, and the mutation of Kcnq1 causes a cardiac long QT syndrome in humans. Here, we studied stomach lesions in these WTC-dfk rats. The most characteristic pathologic feature in the stomach was the appearance of hypertrophic gastric glands in the stomach body. The hypertrophic cells had many eosinophilic granules in their cytoplasm, and these granules were stained red with Azan stain; stained positively for trypsinogen, amylase, and chymotrypsin; and did not stain positively for pepsinogen when using immunohistochemical analysis. These staining results suggested a metaplasia toward a pancreatic acinar cells. Extensive fibrosis was found in the bottom part of the mucosa of 34-week-old WTC-dfk rats, suggesting a progression of stomach lesions with aging. Although cells that were positive for proliferating cell nuclear antigen were restricted in the area of the glandular neck in WTC control rats, positive cells in WTC-dfk rats were scattered throughout the mucosa. The parietal cells in WTC-dfk rats were negative for KCNQ1 immunohistochemical analysis. These findings indicate that a deficiency in rat Kcnq1 provokes an abnormal proliferation and differentiation of gastric glandular cells.     

Torsion and volvulus of the transverse and descending colon in a German shepherd dog

A German shepherd dog was presented two months after surgery for correction of acute gastric dilatation volvulus. The dog had been diagnosed with exocrine pancreatic insufficiency. Radiographs revealed marked gaseous distension of one loop of intestine with a generalised increase in intestinal gas content. A 360 degrees anticlockwise rotation of the descending and transverse colon, around the longitudinal axis of the mesocolon, was diagnosed at exploratory coeliotomy. The transverse and descending colon appeared uniformly necrotic and an end-to-end colo-colic resection and anastomosis was performed. The dog initially made satisfactory postoperative progress but was euthanased on the third postoperative day after it developed an intestinal intussusception.     

Pancreatic Degenerative Atrophy and Chronic Pancreatitis in Dogs a Comparative Study of 60 Cases

During the years 1977–1980 60 cases of non-neoplastic chronic exocrine pancreatic disease in dogs were investigated clinically and pathologically. The disorders were clinically divided into pancreatic degenerative atrophy (PDA) and chronic pancreatitis. Fifty dogs had PDA and 45 of them were German shepherd dogs. The PDA cases formed both clinically and pathologically a homogeneous group except for 1 case. All the dogs had maldigestion and protease activity was absent from the faeces. General inanition and highly atrophic pancreas were the most typical macroscopic findings. Histologically the exocrine pancreas contained atypical acinar tissue and mononuclear cell infiltrations. Five of the dogs died spontaneously, 4 of them had intestinal torsion and 1 had paralytic ileus.There were 10 dogs with chronic pancreatitis. This group was rather heterogeneous both clinically and pathologically. The pancreas was slightly enlarged and the consistency was firm. The histologic picture was one of fibrous tissue proliferation and inflammatory cell infiltrations in the interstitium. The dogs nutritional state as well as faecal protease activity were normal.     

Laboratory tests for diagnosis of gastrointestinal and pancreatic diseases

The panel of laboratory tests available for diagnosis of gastrointestinal (GI) diseases in dogs and cats is wide, and, recently, several new tests have been developed. This article will focus on advances in laboratory tests that are available for the general practitioner for diagnosis of GI diseases. Laboratory tests for diagnosis of gastric and intestinal infectious diseases include fecal parasite screening tests, enzyme-linked immunosorbent assays for parvoviral enteritis, and some specific bacterial tests like fluorescent in situ hybridization for identification of specific bacteria attached to the intestinal epithelial cells. Serum concentrations of folate and cobalamin are markers of intestinal absorption, but are also changed in exocrine pancreatic insufficiency and intestinal bacterial overgrowth. Hypocobalaminemia is common in GI and pancreatic disease. Decreased serum trypsin-like immunoreactivity is a very sensitive and specific test for the diagnosis of exocrine pancreatic insufficiency in dogs and cats. Serum pancreatic lipase is currently the most sensitive and specific test to identify pancreatic cell damage and acute pancreatitis. However, serum canine pancreas-specific lipase is less sensitive in canine chronic pancreatitis. Increased serum trypsin-like immunoreactivity is also specific for pancreatic damage but is less sensitive. It is very likely that further studies will help to better specify the role of these new tests in the diagnosis of canine and feline pancreatic diseases.     

A microscopical examination of the gastric morphology of the white-tailed rat Mystromys albicaudatus (Smith 1834)

A study of the gastric morphology of Mystromys albicaudatus revealed a sacculated stomach with a papillated, keratinized corpus separated from a distal glandular antrum by a ρ re- gastric pouch. Gastric morphology of this type is defined as bilocular hemiglandular. Although the forestomach of M. albicaudatus bears a superficial resemblance to that of a ruminant, the corpus (and papillae in particular) differ structurally and functionally from the rumen. Whereas rumen papillae are important in absorption, those of M. albicaudatus increase surface area for the attachment of symbiotic bacteria.     

Serum amylase and isoamylase values in dogs with pancreatic disease

Serum amylase and isoamylase values were determined in three groups of dogs. The first group contained control dogs while the other groups contained dogs with confirmed exocrine pancreatic insufficiency and diabetes mellitus respectively. The trypsin-like immunoreactivity test was also carried out on sera from dogs with exocrine pancreatic disease (EPI). A significant difference was detected in the serum amylase values between the three groups which may be of limited diagnostic value. Dogs with EPI had values lower than normal while those with diabetes mellitus had values higher than control dogs. No evidence of exocrine pancreatic insufficiency was found in dogs with diabetes mellitus.     

Bilateral corneoconjunctival dermoids and nasal choristomas in a calf

A 5-day-old Angus x Hereford calf presented for bilateral haired masses on the eyes and nasolabial planum since birth. The masses were surgically excised from the inferonasal cornea and bulbar conjunctiva of both eyes and the left and right side of the dorsomedial nasolabial planum. Histopathology of the excised tissue confirmed bilateral corneoconjunctival dermoids with ectopic lacrimal glands, and bilateral nasal choristomas and ectopic nasal glandular tissue. Surgery was curative and healing was uneventful. Bilateral ocular dermoids in combination with nasal choristomas and ectopic glandular tissue have not been documented previously in cattle.     

Use of pulmonary hydrogen gas excretion to detect carbohydrate malabsorption in dogs

Pulmonary H2 excretion was measured in 10 healthy dogs, in 6 dogs with pancreatic exocrine insufficiency, and in 6 dogs with chronic small intestinal disease. Concentration of expired H2 in fasted healthy dogs was 0.9 +/- 0.1 ppm (mean +/- SEM) and peak H2 concentration of 1.4 +/- 0.2 ppm was detected up to 8 hours after feeding. Dogs with pancreatic exocrine insufficiency had fasting expired H2 concentrations of 3.3 +/- 0.9 ppm, which increased to a mean peak H2 concentration of 28.8 +/- 2.0 ppm 6.5 hours after feeding. Following xylose administration, expired H2 concentrations increased from fasting concentrations of 3.6 +/- 0.9 ppm to peak at 19.0 +/- 2.0 ppm in 1.5 hours. Blood xylose concentrations were diagnostic for carbohydrate malabsorption in 4 of 6 dogs with pancreatic exocrine insufficiency. Plasma p-aminobenzoic acid concentration identified bentiromide maldigestion in all dogs with pancreatic exocrine insufficiency. In 3 pancreatic exocrine insufficient dogs tested, pancreatic enzyme replacement therapy partially corrected carbohydrate malabsorption. Fasting expired H2 concentration was 5.3 +/- 1.3 ppm in dogs with chronic small intestinal disease and increased to a peak H2 of 72.2 +/- 18.0 ppm 7 hours after feeding. Following administration of xylose to dogs with chronic small intestinal disease, fasting expired H2 concentration increased from 3.0 +/- 1.0 ppm to a peak of 35.5 +/- 7.2 ppm at 2 hours. Blood xylose concentration was abnormal in only 2 of 6 dogs with chronic small intestinal disease. Results of these studies indicate that expired H2 analysis can identify carbohydrate malabsorption in dogs with pancreatic exocrine insufficiency or chronic small intestinal disease, and that pulmonary H2 testing is more sensitive than xylose absorption testing for the identification of carbohydrate malabsorption.     

Intestinal choristoma in the subcutis of a dog

A 2-year-old, spayed female, Labrador Retriever-cross presented with a subcutaneous mass of several weeks' duration in the right flank region. Surgical excision and histologic examination were performed. The 1.0-cm-diameter mass was circumscribed, unencapsulated, and cystic with a bilayer wall. The inner layer resembled intestinal mucosa, including a tall columnar lining epithelium, crypt-like glands containing scattered neuroendocrine cells that were strongly immunopositive for synaptophysin, and a supporting lamina propria-like fibrovascular tissue that contained lymphocytes and plasma cells. The outer layer was 1- to 2-mm thick and was composed of intersecting and blending bundles of smooth muscle and collagen. Given the presence of organized intestinal tissues in the subcutis, the lesion was consistent with intestinal choristoma.     

Intestinal adenocarcinoma of the ileocecal junction in a chicken.

An 89-week-old male chicken was presented with signs of depression, emaciation, and weakness. At necropsy, a stricture was found at the ileocecal junction that resulted in blockage and dilation of the ileum proximal to the stricture. Histologically, neoplastic epithelial cells that contained mucin had invaded the intestinal wall and produced a fibrous connective tissue reaction. The lesion was diagnosed as scirrhous intestinal adenocarcinoma.     

Metastasizing seminal vesicle adenocarcinoma in a Wistar rat

An adenocarcinoma in the seminal vesicles of a 15-month-old male Wistar rat from a 30-month inhalation study is described. The rat was killed because of cachexia, apathy and a large palpable mass in the abdominal cavity. Macroscopic examination of the abdominal cavity revealed a 3.8 cm x 3.2 cm yellow-grey to pink mass, firm to soft in consistency. The cut section revealed cystic spaces. Histologically, the mass consisted of epithelial cells arranged in glandular and solid patterns with abundant amounts of connective tissue. Epithelial tumour cells were round-to-cylindrical with round-to-oval basophilic nuclei and one or two prominent nucleoli and a distinct eosinophilic cytoplasm. The glandular structure contained clusters of macrophages in their lumen with eosinophilic cytoplasm and indented nuclei. Extensive necrosis and reactive inflammation were present. The histological features of the small nodules in the pancreas and on the surface of the liver, rectum and urinary bladder resembled those of the primary tumour in the seminal vesicles. Based on these criteria, the neoplasm (mass) was diagnosed as an adenocarcinoma of the seminal vesicles. The immunohistological examination confirmed the diagnosis, i.e. immunostaining was positive for cytokeratins (4, 7, 14, 15, 18, and 19), vimentin, PCNA, and ED(1).     

Infectious stunting and pancreatic fibrosis in broiler chickens in Saskatchewan

Two broiler flocks contained 0.5 and 3% small chickens. The small chickens were approximately one-third the size of their penmates, were very active, and retained much of their chick down. They had distended abdomens with full intestinal tracts, often containing undigested feed. In many, the pancreases were thin, white, and firm because of loss of exocrine tissue and replacement by fibrous tissue. Many had skeletal changes suggestive of rickets. In a survey of 48 broiler flocks for small birds and pancreatic lesions, five flocks had a noticeable incidence of small chickens, varying from less than 1% to a maximum of 2%. In 33 of the flocks surveyed, a low incidence of pancreatic lesions was found in birds at the processing plant. No correlation was found between a noticeable number of small birds at the farm and pancreatic lesions found at processing.     

IMAGING DIAGNOSIS—DUODENAL DIVERTICULUM IN A DOG

A young female Boxer had a history of chronic soft stool. Survey abdominal radiographs were unremarkable. A duodenal diverticulum was identified in abdominal ultrasound and barium upper-gastrointestinal contrast examinations. Before surgery a ^99mTc-pertechnetate study was performed to evaluate for ectopic gastric mucosa in the duodenal diverticulum. Focal abnormal increased radioactivity was identified in the right caudal abdominal quadrant. The diverticulum was excised. Upon histopathologic examination of the duodenal diverticulum, ectopic gastric mucosa was not identified but ectopic pancreatic tissue was found. Mild eosinophilic inflammation within the diverticulum was suspected to be the cause of the mild ^99mTc uptake seen in this dog.     

Glandular structures in the major interlobular and extrapancreatic ducts in the guinea pig

The morphology of the pancreatic duct system did not receive much attention as compared to the microanatomy of the exocrine and endocrine pancreas. The histological peculiarities of the excretory duct system are of major importance especially in laboratory animals like guinea pigs. The paper describes the histological peculiarities of the major interlobular and extrapancreatic ducts in guinea pigs. The pancreatic tissue samples were collected from five guinea pigs. For histological investigation, several pancreatic fragments underwent fixation in 10% buffered formalin and were later processed by the standard paraffin technique. Subsequentially, tissue sections were stained by Goldner's trichrome staining. The mucous substances were assessed by Alcian blue and Periodic acid–Schiff staining methods. The interlobular and main pancreatic ducts in the guinea pig present a simple columnar epithelium surrounded by a thick layer of dense connective tissue. The aforementioned epithelium of the main pancreatic ducts includes principal cells, goblet cells and basal cells. Additionally, the ductal epithelium presents occasional unicellular multiloculated intraepithelial mucous glands and prominent extraepithelial glands. The latter adopts a simple or compound tubular feature. The mucus elaborated by the three glandular types is mostly neutral in goblet cells, predominantly acidic in extraepithelial ductal glands, and a similar amount of acidic and neutral mucin in intraepithelial glands. In conclusion, the epithelium-associated mucous glands in the interlobular and main pancreatic ducts in the guinea pig are restricted not only to goblet cells. A substantial mucous discharge probably with a protecting role against irritative pancreatic juice derives from the main ductal intraepithelial and extraepithelial glands.     

Immunocytochemical detection of amylase, carboxypeptidase A, carcinoembryonic antigen and alpha 1-antitrypsin in carcinomas of the exocrine pancreas of the dog.

The immunocytochemical detection of amylase, carboxypeptidase A, alpha 1-antitrypsin, carcinoembryonic antigen (CEA) and keratin in normal canine pancreatic tissue and in carcinomas of the exocrine pancreas of the dog is described. In the normal pancreas, the acinar cells contain amylase, carboxypeptidase and alpha 1-antitrypsin. The pancreatic ducts react with the antikeratin antibody. Twelve out of 14 pancreatic exocrine carcinomas showed immunoreaction with antiamylase antibody, and 10 with anticarboxypeptidase antibody. Five neoplasms reacted with anti-CEA antibody and three with the anti-alpha 1-antitrypsin antibody. It was not possible to find any systematic difference in the immunocytochemical profiles of acinar, tubular and undifferentiated carcinomas. These results indicate that immunocytochemical marking of amylase and carboxypeptidase is of value in the diagnosis of pancreatic neoplasms in the dog, especially if metastasis is the only material available for study and the tumour does not show any diagnostic feature on routine light microscope preparations.     

Histological Studies on the Endocrine Pancreas in the Dog

Based on histological structure and cellular formation, the endocrine pancreas (pars endocrina pancreatis) (PEP) or pancreatic islet (insulae pancreaticae), was divided into two types in the dog. One type of PEP was the islet of Langerhans. In the glandular lobule, the islet was surrounded by exocrine acini. The other type of PEP, in general, exhibited a feature of a neuro-insular complex. It was found within the interlobular connective tissue of the pancreas. This type of PEP was attached to a nerve bundle or ganglion. In the pancreas of the immature dog, a large population of endocrine cells was recognized to form a blood islet within the neuro-insular complex.     

Pancreatic injury in equine acute abdomen evaluated by plasma trypsin activity and histopathology of pancreatic tissue

In cases of equine acute abdominal disease, where pancreatic damage is suspected, pancreatic damage can be assessed by measuring increased trypsin activity in the plasma of horses suffering intestinal obstruction and severe shock. The pancreas is particularly vulnerable to splanchnic hypoperfusion because it is a highly active tissue. In this study, 10 horses undergoing abdominal surgery for intestinal obstruction were assayed for trypsin activity on admission and, because of extensive intestinal lesions that were not amenable to surgery, euthanasia was selected; the pancreas was removed before euthanasia. Trypsin activity in the plasma of these horses was significantly higher than in healthy horses (196 ng/ml +/- 128.2 versus 28.5 ng/ml +/- 19.2; P = 0.0026). Light and transmission electron microscopy revealed slight to severe lesions of vacuolar degeneration, a few zymogen granules, dilation of the endoplasmic reticulum, and swelling of mitochondria in the exocrine pancreas. The activation of an inflammatory cascade occurring during strangulating intestinal obstruction could increase pancreatic anoxic lesions caused by severe shock and hypoperfusion in the horse. Further studies will show the significance of pancreatic lesions and the ensuing damage in equine acute intestinal obstruction and shock.     

鸭胰腺内高血糖素—,胰岛素—和生长抑素—免疫反应细胞的形态及分布

用ABC免疫组织化学方法,对1 周龄绍鸭胰腺内的高血糖素(A)、胰岛素(B)和生长抑素(D)免疫反应细胞的形态及分布进行了观察。结果表明,上述3 种细胞在全胰的分布及形态有差异。A 细胞主要成群散在于A 胰岛,少数位于混合型胰岛的边缘。D 细胞主要散在于A 胰岛中,少数位于B胰岛和混合型胰岛的边缘。B细胞主要呈团块状分布于B胰岛,少数位于混合型胰岛的中央。在胰外分泌部有散在的A 和D 细胞,位于腺泡及导管上皮细胞之间或结缔组织中。A 细胞形态各异,以多边形为主,多数细胞伸出形态多样的胞质突起,伸达胰岛或其他细胞间。D细胞的形态与A 细胞相似。B细胞形态均一,呈圆形或卵圆形,未见胞质突起,在外分泌部未见到B细胞。