Transit time, bowel

Studies of small bowel transit time have demonstrated a great variability both within and between individuals. When the hydrogen breath test was performed under fasting conditions, using 10 ml of lactulose, the coefficient of variation amounted to 18%. Di Lorenzo et al. [129] showed that variations under fasting conditions are partly accounted for by the phase of the migrating motor complex at the intake of test solution. Moreover, when a lactose-containing meal was used, the coefficient of variation was reduced to 4% [130],... 

Holgate AM, Read NW. Relationship between small bowel transit time and absorption of a solid meal. Dig Dis Sci 1983 28(91 812-819. 

Drug deliveiy to the colon by the oral route depends on gastric emptying and the small-bowel transit time. Drugs taken before meals usually pass out of the stomach within 1 hr, but can take up to 10 hr if taken after a meal. The transit time in the small intestine is relatively constant, ranging between 3 and 4 hr, regardless of various conditions such as physical state, size of dosage form, or presence of food in the stomach [9]. 

Relationship between large-bowel transit time (LETT) and the DCA pool size. Data taken from reference 36. 

Then in 1995, Shoda and colleagues from Japan and Sweden found that gallstone carriers had significantly prolonged small-bowel transit times compared with controls. They too had a two-fold increase in the percentage DCA in bile that was associated with supersaturated bile, in contrast to the unsaturated bile found in the gallstone-free controls. 

Verkijk, M., Vecht, J., Gielkens, H.A.J., Lamers, C., and Masclee, A. (1997) Effects of medium-chain and long-chain triglycerides on antroduodenal motility and small bowel transit time in BignDiseases Sci.,42 1933-1939. 

Figure 26-3. Patients with severe pancreatic exocrine insufficiency (n = 14, mean + SE) show marked alterations of gastrointestinal functions with shortened small bowel transit time, 90% gastric emptying time, and duration of the fed pattern. These alterations are corrected by enzyme replacement therapy ( P <. 05 vs. controls, P <. 05 vs. placebo) (Layer et al., 1997).

Bowel transit time was conqiuted as the time from ingestion of the marker until most of the color appeared in the feces. Transit time decreased from a mean of 52 hours on the low fiber diet to a mean of 38 hours on the higher fiber diet. The inclusion of fruits and vegetables in the diet also increased fecal weight, number of defecations, and fecal excretions of energy, nitrogen, and fat. 

In healthy subjects the differences in the rate of zinc turnover are relatively small and a standard correction can be made. Otherwise repeated measurements of the rate of excretion can be used to extrapolate retention to absorption values at the time for intake of the meal. The retention measurements is done after two weeks to allow for long bowel transit time. The endogenous extretion of 65 Zn during this period is only about 10%. The radionuctide technique with 65 Zn and whole body counting are described in more detail in an other paper (15). 

The authors speculated that cisapride reduced digoxin absorption by accelerating bowel transit time. 

Yukioka H, Rosen M, Evans KT, Leach KG, Hayward MW, Saggu GS. Gastric emptying and small bowel transit times in volunteers after intravenous morphine and nalbuphine. Anaesthesia 1987 42(7) 704-10. 

Variations in gastric emptying rate and small bowel transit times are problems that limit the diagnostic accuracy of the breath hydrogen tests. In the face of an appropriate clinical picture and a negative breath hydrogen test, an alternative diagnostic approach is a therapeutic trial of appropriate antibiotics. ... 

Low-protein, high-carbohydrate foods are important in taking care of autointoxication, kidney and liver problems, manic behavior, and low threshold anger tendencies. High-fiber carbohydrates improve bowel transit time and reduce risk of colorectal cancer. 

The rate of gastric emptying and small bowel transit time. 

Physical inactivity and elevated body mass index (BMI), independent of level of physical activity, are associated with an elevated risk of colon adenoma, colon cancer, and rectal cancer. Individuals with a total higher level of activity throughout life have the lowest risk. Hypotheses for these relationships include the observation that physical activity stimulates bowel peristalsis, resulting in decreased bowel transit time, and the possibihty that exercise-induced alterations in body glucose, insuhn levels, and perhaps other hormones may reduce tumor ceU growth. ... 

Among the many ligands that have been evaluated, " Tc-mebrofenin has shown the best in vivo characteristics, namely high hepatocyte extraction (98%) and a fast clearance (Ti,2= 17 min), a rapid hepatobiliary-to-bowel transit time, and low urinary excretion. Tc-mebrofenin provides excellent visualization of the common bile duct and the gallbladder at serum bilirubin levels as high as 30 mg/100 ml (Fink-Beimett 1995 Krishnamurthy and Turner 1990). 

Bryson JC, Dukes GE, Kirby MG, Heizer WD, Powell JR. Effect of altering small bowel transit time on sustained release theophylline absorption. J Clin Pharmacol ( 9Z9) 29, 733-8. 

Small Bowel Transit Time and Cholesterol Absorption... 

Ledeboer, M., Masclee, A.A., Jansen, J.B., and Earners, C.B. Effect of equimolar amounts of long-chain triglycerides and medium-chain triglycerides on small-bowel transit time in humans. JPEN 19, 5-8, 1995. 

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