Caeca

Blind-darm, m. caecum, -feuer, n. blank fire, -ganger, m. (Expl.) dud misfire, -heit, /. blindness, -kohle, /. underbumed charcoal, -leitwert, m. (Elec.) susceptance. -licht, n. flashlight. 

Milieu conditions in gastrointestinal tract can influence the pectin structure and properties. Under the acid conditions of the stomach (pH 2-4) extraction of pectin from plant cell walls and hydrolysis of side chains can occur. In small intestine (pH 5-6) -elimination of main chains or de-esterification seems to be possible. In caecum and colon (pH 6-8) a strong fermentation of pectin takes place causing depolymerization to oligomers and leading to formation of short chain fatty acids and gases. The presence of OligoGalA is not yet clarified. 

The DE of pectin is slightly decreased in the upper part of GI and as well as in caecum and colon of germfree rats (Table 2). 

Original nectin Ileum K Ileum G Caecum G Colon G... 

Figure I. Pectins isolated from contents of of ileum, caecum and colon as well as from from faeces of a germfree rat (DE 92.6%).

No or very low amounts of galacturonan were found in contents of caecum and colon and in faeces of most of the conventional rats (Table 4). Only in 1 or 2 animals of each group higher galacturonan concentrations were present in the lower parts of gastrointestinal tract as well as in faeces (Figure 3). 

Figure 4. Di- and TriGalA found in colon contents of conventional rats fed with a diet containing low-esterified pectin (above) and in a caecum extract with a standard mixture of OligoGalA (DP 2-5) (below)...

H. Anger, E. Walzel and B. Kahrmann, About the absorption of oligo-galacturonides from caecum of rats. FASEB Meeting (1994), Anaheim/USA Abstr. FASEB J. 8 (1994) A152. 

As mentioned above, yS T cells are numerous in the gut and can produce cytokines in the absence of conventionally presented antigen (Kaufmann, 1996). These cells have been shown to produce IL-4 or IFN-y (Ferrick el al., 1995) and are potentially an important source of these cytokines in the intestinal microenvironment following nematode infection. Supporting this suggestion, IL-4 mRNA has been found in y8 T cells from the caecum of resistant mice immediately following T. muris infection (Lukaszewski and R.K. Grencis, unpublished observations). 

MacDonald, T.T., Choy, M.Y., Spencer, J., Richman, P.I., Diss, T., Hanchard, B., Venugopal, S., Bundy, D.A. and Cooper, E.S. (1991) Histopathology and immunohistochemistry of the caecum in children with the Trichuris dysentery syndrome. Journal of Clinical Pathology 44, 194-199. 

The chicken intestinal microbiota is composed principally of Gram-positive bacteria (Gong et al., 2002). The lactobacilli are predominant in the small intestine (with smaller numbers of streptococci and enterobacteria), whereas the caecal flora is composed mainly of anaerobes and fewer numbers of facultative bacteria. Predominant cultured flora of the ileum of chicken include Lactobacillus, Streptococcus, E. coli and Eubacterium, while Eubacterium and Bacteroides dominated the caecum flora. 

A second example is the colon-specific delivery of glucocorticoids linked to dextran via a succinic acid or glutaric acid spacer [256a]. Such conjugates resist hydrolysis in the upper gastrointestinal tract, but are rapidly degraded by bacteria in the colon and caecum where little drug absorption occurs. 

The same strategy was applied in colon-specific delivery of two corticosteroids used to treat inflammatory bowel disease [20][21], Indeed, budeso-nide /3-D-glucuronide and dexamethasone /3-D-glucuronide underwent ready hydrolysis in the luminal contents of rat colon and caecum. Rat mucosal homogenates were less active, and hydrolysis in human fecal samples was quite low. Based on these and other studies, the prodrugs were found to be suitable candidates for delivery of corticosteroids to the large intestine. 

It is noteworthy, here, that one conunercial source of purified alcohol dehydrogenase is horse liver. There is a considerable quantity of this enzyme in horse liver. It is likely that alcohol arises from fermentation in the caecum of the high content of fibre present in the food of the horse. Hence its liver will be exposed chronically to high concentrations of alcohol, and the liver adapts by synthesising large quantities of the enzyme. 

Threadworm infections are caused by Enterobius vermicularis. The infestation starts when the patient ingests the worm s ova, which then hatch and infect the small intestine. The female threadworms migrate to the caecum and anus so that at night they lay their eggs in the perianal area. The eggs produce a sticky... 

Hyslop, J.J., Stefansdottir, G.J., McLean, B.M.L., Longland, A.C. and Cuddeford, D. (1999) In situ incubation sequence and its effect on degradation of food components when measured in the caecum of ponies. Animal Science 69, 147-155. 

Machelboeuf, D., Poncet, C., Jestin, M. and Martin-Rosset, W. (1996) Use of a mobile nylon bag technique with caecum fistu-lated horses as an alternative method for estimating precaecal and total tract nitrogen digestibility. Proceedings of the 47th Annual Meeting of the European Association for Animal Production, Lillehammer, Norway, p. 269. 

Ulcerative colitis is an inflammatory disease of unknown aetiology with mucosal involvement spreading continuously but to varying extent from the rec-mm to the caecum. 

Pathophysiologically, the normal red cell mass, reflected in haemoglobin level or packed cell volume, decreases in anaemia. The mandatory first step is to identify the cause for this change and correct it, wherever possible, prior to initiating treatment. It makes little sense only to replace iron in a patient who continues to rapidly loose blood from the gastrointestinal tract due to a heavy hookworm infestation or a resectable carcinoma of the caecum. Accordingly, it will be assumed throughout that a... 

De Vries J. ]., T. Collin, C. M. Bijleveld, J. H. Kleibeuker, and R. J. Vonk. The use of complex carbohydrates in barley groats for determination of the mouth-to-caecum transit time. Scand J Gastroenterol 1988 23(8) 905-912. 

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