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R Caprilli

Publications and source records attributed to R Caprilli.

At least 55 records · Page 3Linked to original sources

[Ion transport in the colon].

The large bowel daily absorbs passively 1500 ml of water down an osmotic gradient created by active electrolyte transports. The system is sustained by the enzyme Na(+)-K+ ATPase, the so called sodium-pump, present on the basolateral membrane of colonocytes. Some pathologic conditions may increase the amount of intraluminal water by inhibiting fluid absorbtion or enhancing fluid secretion. Diarrhoea represents the clinical counterpart of these alterations. Three forms of diarrhoea can be recognized on the basis of pathophysiological alterations. Diarrhoea is due to reduced ionic absorbtion, increased secretion or increased endoluminal osmolality. The drugs used to induce bowel actions or gut lavage increase also intraluminal water content by modifying transmural ionic transports. Laxatives or purges act by increasing either water secretion on endoluminal osmolality and therefore may produce systemic idro-electrolyte imbalance. To avoid this inconvenient an isosmotic electrolyte balanced polyethylene glicol solution (PEG-ELS) has been achieved. In addition orally administred PEG-ELS solution cleans the colon during its intestinal transit without producing relevant transmural water-ionic movements. Aim of this article was to describe the normal ionic transport, and its alterations in pathologic and pharmacologic conditions. Details on PEG-ELS were also given. This solution provides for an effective colon preparation for endoscopic or surgical procedures and resulted to be safe for patients with delicate fluid-electrolyte balance.

Bicarbonates↗

[Postoperative recurrence in Crohn's disease].

Intestinal resection in the natural history of Crohn's disease is a forced step. Unfortunately surgery is not curative as disease inexorably recurs. The frequency of recurrence varies according to the definitions adopted, being high when endoscopical criteria are used (70-90% at one year). Among risk factors, the most convincing is a smoking habit. The pathogenesis of recurrence is still unknown. Particular attention was paid to colo-ileal reflux which occurs after the resection of the ileocecal valve. The diagnosis should always be based on morphological criteria (endoscopy or radiology). In fact symptoms occur late and are often uncharacteristic. A particular problem in the management of patients with Crohn's disease is the prevention of post-operative recurrence. Recent randomized, controlled trials of which the first has been published by the authors of this article, demonstrated that the administration of 5-ASA early after resection may prevent, delay or attenuate such recurrences. Cessation of smoking also plays a central role in prevention. The final message is that in active Crohn's disease surgery should not be excessively delayed. Early resection followed by prophylactic treatment seems to improve the quality of life in patients with more severe Crohn's disease.

Aminosalicylic Acids↗

Human colonocytes in primary culture: a model to study epithelial growth, metabolism and differentiation.

The purpose of this work was to set up an in vitro model for the study of normal and pathological functions of the colonic epithelium. We have isolated colonic crypts by mild proteolytic digestion and mechanical dissociation of human biopsy material obtained during colonoscopy. The crypts, free of connective tissue, when placed in culture rapidly attached to the substrate and formed colonies containing over 95% of epithelial cells. Histochemical and ultrastructural characterization of the colonies showed the presence of both absorptive and secretory cells, exhibiting a high degree of differentiation. Proliferative activity occurred mostly during the first 24 h and progressively declined thereafter. The cells survived and maintained differentiated characteristics for at least three days in culture. This method can be used to study normal functions of the colonic epithelium. It may also be employed to investigate both noxious and protective factors in pathological conditions such as inflammatory bowel disease and colorectal neoplasia.

Cell Differentiation↗

Oral mesalazine (5-aminosalicylic acid; Asacol) for the prevention of post-operative recurrence of Crohn's disease. Gruppo Italiano per lo Studio del Colon e del Retto (GISC).

METHODS: A multicentre randomized controlled trial was conducted to evaluate the efficacy of oral mesalazine (5-aminosalicylic acid) for the prevention of post-operative recurrence in 110 patients operated on for Crohn's disease by first intestinal resection. Patients were randomly allocated to receive 2.4 g/day of mesalazine, or no treatment at all. The protocol included colonoscopy with ileoscopy at 6 months and yearly thereafter. Recurrence was defined on the basis of endoscopic criteria and classified as mild or severe. RESULTS: The demographic and pre-trial characteristics were very similar in the two groups of patients. The cumulative proportion of recurrence at 6, 12 and 24 months was significantly lower in the mesalazine group than in untreated group (P = 0.002). At 24 months the cumulative proportions of endoscopic recurrence were 0.52 +/- 0.12 (+/- S.E.M.) and 0.85 (+/- 0.07), respectively. At the same time the cumulative proportions of symptomatic recurrence were 0.18 +/- 0.09 and 0.41 +/- 0.09 (P = 0.006). The cumulative proportions of the severe recurrence was also significantly lower in the mesalazine group (0.17 +/- 0.09 vs. 0.38 +/- 0.09; P = 0.021). CONCLUSIONS: The preliminary results of this study show that administration of oral mesalazine soon after surgery is effective in preventing post-operative endoscopic recurrence in Crohn's disease over a 2-year period. It is estimated that this treatment prevents 39% of all recurrences and 55% of the severe recurrences.

Administration, Oral↗

Increase of circulating gamma/delta T lymphocytes in the peripheral blood of patients affected by active inflammatory bowel disease.

In order to study the role of gamma/delta T cells in the pathogenesis of inflammatory bowel disease (IBD) in humans, we measured the percentage of these cells in the peripheral blood, assessed the ratio of the non-disulphide-linked (delta TCS1) type of T cell receptor (TCR) in the total gamma/delta T cells, studied the co-expression of gamma/delta TCR and accessory molecules CD8 and CD16, and compared these data with both the type and the activity of the disease. Percentage levels and absolute numbers of gamma/delta+ T cells were higher in active patients than in controls (P < 0.05), mainly as a result of an increase of V delta 1+ (delta TCS1) T cell subset (P < 0.05). This trend was strongly retained independently of disease activity and clinical picture. An increased percentage of TCR delta 1+/CD16+ cells was observed in our patients compared with controls (P < 0.05). In contrast, no difference was observed as far as the TCR delta 1+/CD8+ cells were concerned. These results suggest that IBD is associated with an expansion of gamma/delta T cells in peripheral blood, which may play a role in the pathogenesis of these disorders.

Adult↗

Rectal irrigation with short-chain fatty acids for distal ulcerative colitis. Preliminary report.

Colon cells from patients with ulcerative colitis utilize short-chain fatty acids inefficiently and may be exposed to decreased concentrations of these compounds. To test whether irrigation of the inflamed mucosa with short-chain fatty acids is useful, we conducted a six-week preliminary trial in 12 patients with distal colitis. Each patient used twice daily rectal irrigations with 100 ml of a solution containing acetate (80 mM), propionate (30 mM), and butyrate (40 mM). Two patients stopped at three weeks, one because of no improvement and the other because of complete resolution of symptoms. Of the 10 who completed the trial, nine were judged to be at least much improved and showed a change in a mean disease activity index score from 7.9 +/- 0.3 (SE) to 1.8 +/- 0.6 (SE) (P less than or equal to 0.002) and in a mucosal histology score from 7.7 +/- 0.7 (SE) to 2.6 +/- 0.7 (SE) (P less than or equal to 0.002). Thus, ulcerative colitis patients appear to benefit from increased contact with or higher than usual levels of these critical energy substrates.

Acetates↗

Abnormalities of colonic mucin secretion and metabolic changes after internal urinary diversion for bladder exstrophy. A prospective study.

Ten patients with different types of internal urinary diversion for bladder exstrophy were studied prospectively in order to assess metabolic abnormalities and morphological, histochemical and lectin binding changes in the colorectal mucosa. The histochemical and/or lectin binding changes which were found in the majority of patients were identical to those observed in premalignant and malignant conditions of the colon. In some cases they were detectable 3 years after the initial examination but were completely absent from the colorectal mucosa of normal subjects. Metabolic disturbances (metabolic acidosis, increased anion gap, hyperchloraemia) were observed in a substantial number of asymptomatic patients. These findings stress the need for regular endoscopic, histological and metabolic follow-up in these patients and for life-long treatment with bicarbonate or citrate.

Adolescent↗

Do colon and rectum exhibit an opposite cancer risk trend versus cholecystectomy? A case--double control study.

A case-double control study on 318 personally interviewed patients with large bowel neoplasia has been carried out to establish the possible role of cholecystectomy in the development of colorectal cancer. The dietary habits both of the cancer patients and control subjects were investigated. All controls were considered free of neoplastic lesions on the basis of a negative fecal occult blood test. Data from the study showed that the prevalence of cholecystectomy in the overall patients was similar to that of the two control groups. However, analysing the data for colon and rectum, the relative risk of colonic cancer after cholecystectomy was significantly increased in males (RR = 2.75; p less than 0.05), whereas that of rectal cancer appeared to be decreased in females (RR = 0.18; p less than 0.02). Subsite analysis demonstrated that right-sided neoplasia after long-standing cholecystectomy (greater than or equal to 10 years) was responsible for the increased colonic risk. In conclusion, the present data support the hypothesis that cholecystectomy may be considered a risk factor for right-sided colon cancer, but indicate that this operation seems to play a protective role for rectal cancer.

Aged↗

Fecal lactate and ulcerative colitis.

Impaired metabolism of short-chain fatty acids, as well as a modified fecal ionogram, have been reported in ulcerative colitis. Fecal water samples from 62 patients with ulcerative colitis were analyzed in the present investigation to evaluate changes in SCFAs and lactic acid in relation to activity and severity of disease. Short-chain fatty acid levels were high in quiescent and mild disease (162.6 +/- 63.6 and 147.8 +/- 63.2 mM/L, respectively), but significantly decreased in the severe form (64.7 +/- 46.9 mM/L). Lactate showed a progressive increase from mild colitis (3.0 +/- 1.8 mM/L) to severe colitis (21.4 +/- 18.6 mM/L). It thus appears that mild colitis displayed a fecal pattern characterized by normal pH and bicarbonate, slightly impaired electrolyte handling, high short-chain fatty acid values, and only moderately increased lactate. Severe colitis, on the other hand, was characterized by low fecal pH, bicarbonate, and potassium, high sodium and chloride, low short-chain fatty acid levels, and very high lactate levels. A critical lowering of intraluminal pH, which shifts bacterial metabolism from short-chain fatty acid to lactate production, may be responsible for the intraluminal pooling of lactate.

Colitis, Ulcerative↗

Early recognition of toxic megacolon.

Increased amounts of small bowel gas are a frequent finding on plain abdominal films in toxic megacolon (TMC), but they may also be found in patients with severe colitis. We studied 69 consecutive patients with severe ulcerative colitis to evaluate whether an increased gas content of the small intestine may identify patients prone to TMC. The intestinal gas was measured on plain abdominal films by means of a planimeter. On the basis of gas values, 38 patients showed a normal and 31 an increased amount of small intestinal gas. The outcome of the disease (complications, need for surgery, and mortality rate) and 18 clinical and hematochemical findings were compared in the two groups. Of the 31 patients with increased gas, seven developed TMC, whereas this complication was not observed in the 38 patients with normal gas. The only other different features between the two groups were blood pH and base excess, which were significantly higher in the patients with increased small bowel gas content. We therefore suggest that persistent abnormal gaseous distension of the small bowel, together with severe metabolic alkalosis, characterizes a subgroup of patients with severe colitis at high risk for the development of TMC. The strict surveillance of these patients led to early recognition of seven cases of TMC and prompt institution of aggressive medical treatment. Since all these patients survived, the early detection of TMC may improve prognosis.

Adolescent↗

Seeking clues for a positive diagnosis of the irritable bowel syndrome.

Despite its high prevalence the irritable bowel syndrome (IBS) lacks acceptable pathophysiological markers and its diagnosis largely depends on the exclusion of underlying organic disease. Systemic acid-base balance, serum electrolytes and the composition of faecal water (electrolytes and organic anions), were studied in thirty-eight diarrhoeal patients out of a series of ninety-three consecutive IBS patients. Only patients with diarrhoea as the predominant symptom were included in the study to evaluate whether this subgroup could provide the clue for a positive diagnosis of the syndrome. Serum electrolytes and systemic acid-base balance were within the normal range. Faecal electrolytes were also normal (Na 26.6 +/- 19.3 SD; K 66.8 +/- 28.3; Cl 19.1 +/- 15.2 mEq 1(-1)), despite the finding of a moderately increased 24-h faecal output. The K:Na ratio was also within the normal range. These data are in agreement with the lack of systemic changes observed in IBS patients even with profuse or longstanding diarrhoea. Both faecal short chain fatty acids and lactic acid were increased in patients vs. controls, but a considerable overlap with normal values was observed (131.4 +/- 62.6 SD vs. 108.5 +/- 58.3 mEq 1(-1). Only lactic acid concentration was significantly higher than in controls (1.3 +/- 1.2 vs. 0.5 +/- 0.2). Despite these findings it is concluded that the subgroup of IBS patients with diarrhoea also appears to lack a pathophysiological marker and does not provide clues for a positive diagnosis of this syndrome.

Acid-Base Equilibrium↗

Report of a family with hereditary site-specific colon cancer.

A large family with a high prevalence of colorectal cancer, presenting the major features of hereditary site-specific colon cancer (i.e., autosomic dominant model of heredity, absence of associated adenomatous polyposis, prevalence of right-sided colonic lesions, and young age of the patients) is described. The lack of association with solitary adenomatous polyps, the higher survival rate of patients with left-sided colon cancer, and the absence of extracolonic tumors were peculiar characteristics of this family. These data, in agreement with other reports, appear to suggest that the inherited colon cancer syndromes are not a single entity, but a group of related entities linked by their familial occurrence.

Adenocarcinoma↗