Affect the Bowel

Not all calcium present in the diet is absorbed by the small intestine and mechanisms are present to ensure only amounts appropriate to body needs are absorbed. These processes are complex and involve the interaction of special transport protein, vitamin D and parathormone. Thus, abnormalities of calcium metabolism may result from many different disease processes. Diseases affecting the bowel may prevent normal absorption, diseases of the parathyroid gland may result in inappropriate levels of parathormone for calcium requirement and a nutritionally inadequate diet may cause vitamin D deficiency with consequent disordered calcium absorption. 

Numerous studies suggest that the development of colorectal cancer can be caused or promoted by dietary or environmental factors that affect the bowel, lifestyle choices, and certain comorbid conditions, in addition to physical and genetic susceptibilities. 

Inflammation. Chronic inflammatory bowel disease affecting the small bowel can lead to disturbances of intestinal motility [146], Potential mechanisms are previous surgery, development of fibrosis and strictures, malabsorption, and cross-talk between inflammatory and enteric nerves [156, 157], Patients with Crohn s disease are often included in aggregate studies of bacterial overgrowth [23, 75, 158], reflecting this link. 

The neuromuscular compartment of the bowel wall is also affected in certain types of the Ehler-Danlos syndrome [162], maybe in amyloidosis [163], and in the presence of diffuse lymphocytic infiltration [164],... 

Intestinal pseudoobstruction is also part of paraneoplastic syndromes. The anti-/zu antibodies are useful to indicate this condition, as shown in bronchial small cell carcinoma [171], In pheochromocytoma [172] and carcinoid [173] neuromediators affecting small bowel motility are produced by the tumor cells. Intestinal pseudoobstruction has also been reported in neuroblastoma [174],... 

Release results with this method are shown in Figure 11. The BioDis method enables the release pattern to be interpreted in terms of release at sites of inflammation. In Crohn s disease, the inflammation often starts at the ileocecal junction and spreads from there in the proximal and/or distal direction and may affect the entire GI tract in severe cases, whereas in colitis the inflammation is restricted to the large bowel. The release patterns in Figure 11 can be used in combination with a knowledge of the sites of inflammation in a given patient to choose the most suitable dosage form available on the market for that patient (Klein, 18). 

Inflammatory Bowel Disease (IBD) comprises several diseases, including ulcerative colitis and Crohn s disease. Ulcerative cohtis is a disease of the colon, originating in the rectum and extending proximally to a variable extent. It frequently affects the entire colon but never... 

Pharmacology Loperamide slows intestinal motility and affects water and electrolyte movement through the bowel. It inhibits peristalsis by a direct effect on the circular and longitudinal muscles of the intestinal wall. It reduces daily fecal volume, increases viscosity and bulk density and diminishes the loss of fluid and electrolytes. Pharmacokinetics ... 

The drug affects the scolex and proximal segments of the cestodes, resulting in detachment of the scolex from the intestinal wall and eventual evacuation of the cestodes from the intestine by the normal peristaltic action of the host s bowel. Because niclosamide is not absorbed from the intestinal tract, high concentrations can be achieved in the intestinal lumen. The drug is not ovicidal. 

The most common causes of vitamin B12 deficiency are pernicious anemia, partial or total gastrectomy, and conditions that affect the distal ileum, such as malabsorption syndromes, inflammatory bowel disease, or small bowel resection. 

Lu Hui is very bitter and cold, and enters the Liver, Heart, Stomach and Large Intestine meridians. It is a very strong herb to purge the bowels and reduce excess heat. It directly drains Liver-fire and Heart-fire. It is selected when the heat of Heart and Liver affects the Stomach and Large Intestine. 

The chemical action of these substances includes neutralization of gastric HCI, which in turn affects the action of pepsin in the stomach and the binding of intestinal phosphate. Laxatives also stimulate the muscles of the lower bowel as well as absorb water themselves. All of the drugs listed above decrease the Gl absorption of other drugs and therefore should not be taken with other drugs. 

Morphine and other opium alkaloids affect the activity of the bowel and have long been used in antidiarrhoeal medicines. Pethidine has a similar effect, and the piperidine diphenoxylate (142) is effective in the treatment of diarrhoea in doses that do not produce any CNS effects. 

A 53-year-old man developed ileocecal intussusception due to an edematous ischemic cecum, due to enterocolic lymphocytic phlebitis, with numerous associated thrombi. The phlebitis involved not only the ischemic area but also other sites, notably the entire right colon, terminal ileum, and appendix. All layers of the bowel wall were involved. The mesenteric veins were also prominently affected, but the arteries were spared. There was a marked lymphocytic infiltrate involving the epithelium of the entire right colon, ileum, and appendix. 

Finally, activation of the sympathetic division tends to result in a more massive and diffuse reaction than does parasympathetic activation. Parasympathetic reactions tend to be fairly discrete and to affect only one organ or tissue. For instance, the parasympathetic fibers to the myocardium can be activated to slow down the heart without a concomitant emptying of the bowel through an excitatory effect on the lower gas-... 

Octreotide inhibits intestinal secretion and has dose-related affects on bowel motility. In low doses (50 ug subcutaneously) it stimulates motility, whereas at higher doses (eg, 100-250 Mg subcutaneously), it inhibits motility. Octreotide is effective in higher doses for the treatment of diarrhea due to vagotomy or dumping syndrome as well as for diarrhea caused by short bowel syndrome or AIDS. Octreotide has been used in low doses (50 Mg subcutaneously) to stimulate small bowel motility in patients with small bowel bacterial overgrowth or intestinal pseudoobstruction secondary to scleroderma. 

Acarbose is a glucopyranose derivative that acts by inhibiting intestinal a-gluco-sidase. This delays carbohydrate absorption and reduces the postprandial (1.5 hours after food) blood glucose levels and is used in combination with other sulfonyl-ureas. Acarbose may cause GI disturbances, flatulence, abdominal distortion, diarrhea, and pain. Acarbose should be avoided during pregnancy, as it affects the fetus. Acarbose is contraindicated in inflammatory bowel disease and hepatic dysfunction. 

The columnar epithelial cells of the intestinal mucosa actively absorb and secrete extracellular ions, nutrients, and water. The active secretion of ions by these cells with an accompanying fluid flux acts to dilute and purge microorganisms or toxins in the bowel promotes the transfer of secretory immunoglobulin A, antimicrobial defensin peptides, and mucin into intestinal mucus and the gut lumen and, by affecting intraluminal pH, may alter the growth characteristics of enteric microflora [121]. Mucosal secretion is modulated by several enteric neurotransmitters, as well as inflammatory mediators released by mucosal mast cells that may affect transport indirectly through their ability to stimulate enteric neurons [122],... 

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