Disorders of the small intestine and vermiform appendix
Alfred Cuschieri, George Hanna in Essential Surgical Practice, 2015
Anatomy The small intestine is divided into three anatomical portions: duodenum, jejunum and ileum. However, in surgery, the duodenum, which forms the first 25 cm, is considered with the stomach because of various pathologies which affect both organs, such as peptic ulceration. At postmortem the average length of the small intestine in situ is about 7 m, with a reported range of 4.3-10.3 m when the measurement is made along the antimesenteric border. These estimates have to be regarded as approximate and are certainly not exact in view of the distensibility of the small intestine, the flaccid state after death and indeed the method of measurement (usually by tape) used in these postmortem studies. The length of the intestine (less the duodenum) when measured along its attached or mesenteric border, is only 4.6 m.
Answers Paper 2
Anna Kowalewski, Priya Jeevananthan in Get Ahead! Basic Sciences, 2017
Peyer patches are generally found in the ileum and Brunner glands are typically found in the duodenum, although they can be found in other places throughout the gastrointestinal tract. Meckel diverticula are classically found in the ileum as a persistence of the embryonic vitelline (omphalomesenteric) duct. ey aect 2% of the population, are usually located 2 feet from the ileocaecal valve, are 2 inches in length and involve two types of ectopic tissue (gastric and pancreatic). Patients oen present at 2 years of age and males are twice as likely to be aected. Valvulae conniventes (also known as circular folds, plicae circulares or valves of Kerckring) are largest in the proximal half of the jejunum.
Small Bowel Tumors
Michael H. Torosian in Integrated Cancer Management, 1999
Small bowel tumors are rare, which is surprising when one considers that the total length of the duodenum, jejunum, and ileum is much greater than that of the remaining gastrointestinal tract. One-third of small bowel tumors are benign and two-thirds are malignant. They comprise 1-3% of all gastrointestinal tumors and occur 36-60 times less frequently than malignancies of the colon. It was estimated that there will be an estimated 4900 new cases of cancer of the small intestine in the United States in 1997. These tumors occur most frequently in the sixth and seventh decades of life, with a slight male predominance. There are more than 1000 deaths annually in the United States from primary malignant small bowel tumors.
The Intestinal Phase of Gastric Secretion
Published in Scandinavian Journal of Gastroenterology, 1976
P. Grabner, L. S. Semb, E. Schrumpf, J. Myren
Grabner, P., Semb, L. S., Schrumpf, E., & Myren, J. The intestinal phase of gastric secretion. Response to liver extract infusion into the proximal jejunum of healthy human subjects. Scand. J. Gastroent. 1976, 11, 415-419. A Levine tube was placed under radiological control in the stomach, and a thin polyethylene tube in the proximal jejunum of 6 healthy volunteers. The stomach and proximal part of jejunum were perfused for 2 hours with 1% acetylcholine, 20% meat extract (Bovril), and 15% liver extract (LE) alone and in combination with simultaneous infusion of different doses of exogenous pentagastrin intravenously. A significant increase in serum gastrin concentration was found with antral perfusion of LE only, whereas perfusion of the proximal jejunum did not change the basal level of the serum gastrin concentration. No change from control values was observed in gastric acid, and pepsin output on perfusing proximal jejunum with LE alone, or in combination with pentagastrin. Reflux to the stomach varied between 0-1.4%, as determined by addition of radioactive B12 to the perfusates. The experiments showed that gastrin was released from the antrum of the stomach by perfusion with 15 per cent LE, but not from the jejunum under the present experimental conditions. In the present experiments Bovril and acetylcholine perfusions did not cause significant responses from the antrum or from the proximal jejunum.
Lack of Response to Dietary Protein in Pancreatic Secretion by Chronic Deprivation of Jejunal Chyme in Rats
Published in Scandinavian Journal of Gastroenterology, 1996
Background: Exocrine pancreatic secretion is regulated by luminal factors, bile-pancreatic juice (BPJ), and food chyme. The effects of 10 days' chronic deprivation of luminal chyme on the stimulation of exocrine pancreatic secretion by dietary protein were examined in rats with or without BPJ in the jejunum. Methods: The jejunum was deprived of ingested food by preparing a whole-jejunum blind loop. The BPJ was diverted by a common bile-pancreatic duct catheter and was returned to the upper jejunum (with BPJ) or ileum (without BPJ). Results and Conclusion: In rats with the ingested food and BPJ in the jejunum (control), secretion rates in terms of volume, protein, amylase, and trypsin increased more than twofold from the rates in the fasting state after a jejunal injection of peptic hydrolysate of casein. In contrast, the secretions were not increased by the protein injection in the rats deprived of jejunal chyme with or without BPJ in the jejunum. Even in the chyme-deprived group the protein and trypsin secretion of the fasting state was significantly higher in BPJ-diverted rats than in rats with BPJ. These results showed that chronic deprivation of the jejunal chyme impaired responses of the exocrine pancreas to dietary protein but not the hypersecretions of the pancreas by BPJ diversion.
Effects of Nigella sativa Seeds on Intestinal Smooth Muscle
Published in International Journal of Pharmacognosy, 1993
The spasmolytic effects of an ethanol extract and the volatile oil of Nigella sativa seeds were tested in vitro using isolated segments of rabbit jejunum. The ethanol extract and volatile oil inhibited spontaneous movements of the rabbit jejunum. Also, the volatile oil inhibited contractions of the rabbit jejunum which were induced by high potasium (K+) solution or acetylcholine. This inhibition was dose-dependent, reversible and not affected by the addition of calcium to the organ bath. These data suggest that the plant seed has an antispasmodic effect, possibly due to a calcium antagonistic activity.