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Biomedical subjects

P Domizio

Publications and source records attributed to P Domizio.

At least 19 recordsLinked to original sources
PubMed1999

Cisplatin impairs fluid and electrolyte absorption in rat small intestine: a role for 5-hydroxytryptamine.

BACKGROUND: The antineoplastic drug cisplatin has been widely used for the treatment of cancer in humans but its use has been limited by vomiting and diarrhoea. Cisplatin releases 5-hydroxytryptamine into the gut which is thought to be the major mediator of cisplatin induced vomiting. AIM: To determine whether cisplatin affects fluid and electrolyte transport in rat jejunum and whether this change can be modulated by the 5-hydroxytryptamine3 receptor antagonist, ondansetron. METHODS: Jejunal perfusion in rats in vivo was performed one hour after intraperitoneal cisplatin (5 and 10 mg/kg) administration. The effect of pretreatment with subcutaneous ondansetron 300 microg/kg was investigated. RESULTS: Median net fluid absorption after cisplatin 10 mg/kg (67 microl/min/g dry intestinal weight (interquartile range 46 to 100); n = 15) was reduced compared with controls (120 (107 to 151) microl/min/g; n = 13; p<0.001). Ondansetron reversed the impairment of jejunal fluid absorption produced by cisplatin to normal (161 (130 to 176) microl/min/g; n = 11; p<0.001). Electrolyte movement paralleled fluid movement. Jejunal histological examination of sections from cisplatin treated animals showed villus damage, which was not prevented by pretreatment with ondansetron. CONCLUSION: These findings suggest that diarrhoea during cisplatin therapy may be due to altered fluid transport in the small bowel. The reversal of fluid transport to normal in the presence of a 5-hydroxytryptamine3 receptor antagonist suggests that 5-hydroxytryptamine is a local mediator in the small intestine.

Animals↗
PubMed1998

Does CagA contribute to ulcer pathogenesis in a developing country, such as Sudan?

BACKGROUND AND OBJECTIVE: In Western populations, peptic ulcer disease is closely associated with Helicobacter pylori (H. pylori) strains expressing the CagA antigen. In Africa the prevalence of H. pylori infection and peptic ulcer disease is high, although information regarding potential virulence factors is lacking. This study examines the prevalence of antibodies to CagA both in African patients with dyspepsia who are undergoing gastroscopy, and in asymptomatic healthy African volunteers. METHODS: Eighty two consecutive patients (median age 34 years, range 15-73 years), attending for gastroscopy were studied, of whom 78 (95.1%) were subsequently found to be Helicobacter positive. Three antral biopsies were obtained from each patient and 5 ml of blood was taken for determination of CagA seropositivity using western blot analysis. CagA seropositivity was also determined in 65 H. pylori positive healthy volunteers (median age 30 years, range 18-70 years), with no symptoms or previous history of gastroduodenal disease. RESULTS: Of the 78 H. pylori positive patients, CagA seropositivity was present in all 22 patients with active peptic ulcer disease (100%), in eight of nine patients with duodenitis (89%), in 15 of 19 patients with macroscopic gastritis (78.9%), and in 24 of 28 patients with a normal endoscopy (85.7%). On histological assessment, 46 patients had chronic active gastritis, 29 patients had gastritis with atrophy and three patients had intestinal metaplasia. CagA seropositivity rates were 84.7%, 93% and 100%, respectively, for these groups. In the 89 healthy volunteers studied, 57 of the 65 H. pylori positive subjects (87.7%) were seropositive for the CagA protein. CONCLUSIONS: As in Western countries, CagA seropositivity in this African population was closely related to endoscopic gastroduodenal disease, and to the presence of more advanced histological lesions in the antrum. However, there was also a high prevalence of CagA seropositivity in asymptomatic healthy individuals, suggesting that factors other than CagA predominate in ulcer pathogenesis in this population.

Adolescent↗
PubMed1998

The relation between gastric vitamin C concentrations, mucosal histology, and CagA seropositivity in the human stomach.

BACKGROUND: Vitamin C may be protective against gastric cancer though infection with Helicobacter pylori is associated with a reduction in intragastric concentrations of vitamin C. AIMS: To examine the effects of H pylori infection, gastric juice pH, the severity and extent of gastric inflammation, and CagA antibody status of the individual on gastric juice and mucosal vitamin C concentrations. PATIENTS: One hundred and fifteen patients undergoing routine gastroscopy for investigation of dyspepsia. METHODS: High performance liquid chromatography was used to determine vitamin C concentrations. CagA antibody was detected by western blot analysis. RESULTS: Gastric juice ascorbic acid concentration was significantly lower in patients infected with H pylori compared with those uninfected (19.3 mumol/l (interquartile range (IQR) 10.7-44.5) versus 66.9 mumol/l (IQR 24.4-94.2), p = 0.003). The reduction in gastric juice ascorbic acid concentration was inversely related to the severity of gastritis (p = 0.01). CagA positive patients had significantly lower gastric juice ascorbic acid concentrations than CagA negative ones (14.8 mumol/1 (IQR 7.9-52.2) versus 39 mumol/l (IQR 19.9-142.2), p = 0.05). Decreased gastric juice dehydroascorbic acid concentrations were observed in patients with gastric atrophy and intestinal metaplasia. Mucosal ascorbic acid concentrations were also significantly lower in infected patients than uninfected patients (p = 0.04). CONCLUSIONS: The reduction in gastric vitamin C concentrations is related to gastric juice pH, the severity and extent of gastritis, the presence of H pylori, and the CagA antibody status of the individual. These findings may have implications in H pylori associated carcinogenesis.

Adult↗
PubMed1997

Secondary products formation as a tool for discriminating non-Saccharomyces wine strains. Strain diversity in non-Saccharomyces wine yeasts.

A total of 78 strains of non-Saccharomyces yeasts were isolated: 30 strains of Kloeckera apiculata, 20 of Candida stellata, 8 of Candida valida and 20 of Zygosaccharomyces fermentati. The diversity of yeast species and strains was monitored by determining the formation of secondary products of fermentation, such as acetaldehyde, ethyl acetate and higher alcohols. Within each species, the strains were distinguishable in phenotypes through the production of different amounts of by-products. In particular, a great variability was found in C. stellata, where six different phenotypes were identified by means of the production of acetaldehyde, ethyl acetate, isobutanol and isoamyl alcohol. At different stages of the spontaneous fermentation different phenotypes of the non-Saccharomyces yeasts were represented, characterized by consistent differences in some by-products involved in the wine bouquet, such as acetaldehyde.

Acetaldehyde↗
PubMed1996

Endoscopic assessment of the colonic response to corticosteroids in children with ulcerative colitis.

Twenty children with active ulcerative colitis were assessed before and after 8 weeks of medical therapy with 5-aminosalicylic acid (5-ASA) derivatives and corticosteroids. Local therapy was given for distal disease (seven cases); other disease was treated with oral prednisolone (1-2 mg/kg/day, maximum 40 mg). Eighteen of the children showed a clinical improvement on therapy, and complete remission of clinical disease activity by 8 weeks was seen in 17 (85%). C-reactive protein was elevated initially in 10 of 20 children and returned to normal posttreatment in all but one. Reassessment of the colon after treatment showed an improved endoscopic appearance in 15 and complete remission in eight (40%). Histological improvement was seen in 13, with full remission in only three (15%). In conclusion, remission of clinical disease activity by corticosteroid therapy in ulcerative colitis may not be accompanied by endoscopic remission and uncommonly by mucosal healing. This finding may be important prognostically because of the risk of dysplasia in long-standing persistent mucosal inflammation.

Adolescent↗
PubMed1996

Determination of 2,3-butanediol in high and low acetoin producers of Saccharomyces cerevisiae wine yeasts by automated multiple development (AMD).

High performance thin layer chromatography with automated multiple development was used to determine 2,3-butanediol levels in wine produced by high and low acetoin-forming strains of Saccharomyces cerevisiae. An inverse correlation between acetoin and 2,3-butanediol content was found suggesting a leaky mutation in acetoin reductase of the low 2,3-butanediol producing strains.

Acetoin↗
PubMed1996

Ornithine decarboxylase activity is a marker of premalignancy in longstanding Helicobacter pylori infection.

BACKGROUND: Longstanding Helicobacter pylori infection may increase the risk of developing gastric adenocarcinoma. The sequence of chronic active gastritis leading to gastritis with atrophy and subsequent intestinal metaplasia is thought to be a key step in gastric carcinogenesis. Ornithine decarboxylase (ODC) activity is increased in some pre-malignant gastrointestinal conditions and is essential for malignant transformation in vitro. AIMS: To measure ODC activity in the antrum of H pylori infected and non-infected subjects and to relate this to histological abnormalities associated with recent and longstanding H pylori infection. METHODS: Six antral mucosal biopsy specimens were obtained from 75 patients for detailed histological assessment and measurement of ODC activity. Samples were measured in duplicate and results expressed as median, interquartile range in pmol/mg protein/h. RESULTS: ODC activity was significantly higher in H pylori positive (164, 88-259 pmol/mg/h) than H pylori negative subjects (99.8, 55-158 pmol/mg/h, p = 0.003). However the presence of gastritis, irrespective of the severity of inflammation or activity had no influence on ODC activity. Gastritis with atrophy was associated with increased ODC activity, which was closely related to the severity of the atrophy (p = 0.01). Similarly, ODC activity was significantly increased in subjects with intestinal metaplasia (196, 83-25) compared with those without intestinal metaplasia (111.7, 65-175, p < 0.04). CONCLUSIONS: These results indicate that the histological changes associated with longstanding H pylori infection rather than inflammation alone are associated with increased polyamine biosynthetic activity. This may be relevant to H pylori associated gastric carcinogenesis.

Adolescent↗
PubMed1995

A randomized prospective comparison of clarithromycin versus amoxycillin in combination with omeprazole for eradication of Helicobacter pylori.

AIM: To compare H. pylori eradication rates using omeprazole in conjunction with either amoxycillin or clarithromycin. BACKGROUND: Omeprazole with amoxycillin is the most widely used dual therapy regimen for eradication of H. pylori. A recent open study suggested a high eradication rate combining omeprazole with the newer macrolide, clarithromycin. METHODS: A randomized prospective trial in 54 patients was conducted to compare 2 weeks of treatment with omeprazole 40 mg once daily and either amoxycillin 500 mg three times daily or clarithromycin 500 mg three times daily. H. pylori eradication was assessed using the 13C urea breath test. RESULTS: Eradication was achieved in 18/26 (69.2%) of subjects treated with omeprazole and amoxycillin and 18/25 (72.0%) of those treated with omeprazole and clarithromycin (P = N.S.). Minor side effects, most commonly altered taste, were reported by 16% of patients and were more frequent in those randomized to clarithromycin (P = 0.01). CONCLUSIONS: These regimens are similarly effective. However, clarithromycin is more expensive, associated with a greater frequency of side effects and, unlike amoxycillin, resistance by H. pylori has been reported. This suggests that clarithromycin may be a useful alternative when there is penicillin allergy or previous treatment failure, but it should not replace amoxycillin as first choice in omeprazole-based dual therapy.

Adolescent↗
PubMed1995

The effect of treatment on lymphokine-secreting cells in the intestinal mucosa of children with Crohn's disease.

BACKGROUND: Recent studies have shown both interleukin 2 (IL-2) and interferon gamma (IFN) to be elevated in patients with active Crohn's disease compared to ulcerative colitis or non-inflammatory bowel disease controls. However the effect of treatment on these lymphokines has not been studied. PATIENTS AND METHODS: Using a reverse haemolytic plaque assay the percentage of lymphokine-secreting cells was determined in the intestinal mucosa of children with Crohn's disease before and after 8 weeks of treatment with either enteral nutrition, cyclosporin or steroids. RESULTS: Before treatment, a high percentage of cells isolated from mucosal biopsies secreted IL-2 or interferon-gamma. Eight weeks' treatment with the immunosuppressive agents cyclosporin, or with corticosteroids, produced a significant reduction in the percentage of IL-2 secreting cells, although only for the former was there also a reduction in interferon-gamma secreting cells. Enteral nutrition however, produced a reduction in lymphokine-secreting cells equivalent to cyclosporin and produced the best histological and clinical improvement. CONCLUSION: Enteral nutrition and cyclosporin can down-regulate lymphokine secretion in the gut in Crohn's disease.

Adolescent↗
PubMed1994

Tumor necrosis factor alpha-producing cells in the intestinal mucosa of children with inflammatory bowel disease.

BACKGROUND/AIMS: Cytokines are thought to be important in mediating tissue damage in inflammatory bowel disease (IBD). Many of the in vivo activities of tumor necrosis factor alpha (TNF-alpha) match the changes found in IBD, but its importance is controversial. METHODS: A sensitive, reverse hemolytic plaque assay was used to determine the frequency of TNF-alpha secreting cells isolated from mucosal biopsy specimens of children with Crohn's disease or ulcerative colitis (UC) and non-IBD controls before and after medical treatment. RESULTS: Frequency of TNF-alpha secreting cells was significantly increased in biopsy specimens from children with mild, nonspecific inflammation compared with those with histologically normal intestine. Frequency did not increase in UC compared with children with nonspecific inflammation but was significantly greater in Crohn's disease than in UC. After treatment, the frequency of TNF-alpha secreting cells was reduced in patients receiving cyclosporin A, not reduced in patients with steroids or enteral nutrition, and not changed with treatment in UC. CONCLUSIONS: TNF-alpha secreting cells are increased in the mucosa of inflamed intestine, regardless of pathogenesis. In patients with IBD, higher levels are seen in Crohn's disease than in UC, probably reflecting the extensive T-cell activation in Crohn's disease. No relation existed between histological healing and the frequency of TNF-alpha-secreting cells.

Adolescent↗
PubMed1994

Pathology of chronic inflammatory bowel disease in children.

The term chronic inflammatory bowel disease is usually applied to the idiopathic varieties ulcerative colitis and Crohn's disease but actually encompasses a wide range of colonic inflammatory conditions, which in children includes indeterminate colitis, microscopic colitis, allergic colitis and Behçet's enterocolitis. The pathologist's opinion is considered the final arbiter in the diagnosis of inflammatory bowel disease but classification may be hampered by the considerable histological overlap between the various types of colitis. Accurate diagnosis, particularly in biopsy specimens, thus depends on clinical and radiological input as well as on appropriately selected and adequately prepared material. This chapter discusses in detail the morphological appearances of ulcerative colitis and Crohn's disease with particular emphasis on diagnosis by mucosal biopsy and differential diagnosis in the paediatric age group. The recent demonstration of ulceration-associated cell lineage and trefoil peptide expression in inflammatory bowel disease is also discussed.

Child↗
PubMed1994

Neurological illness following treatment with fludarabine.

Fludarabine is a comparatively new drug for the treatment of low-grade lymphoid malignancy. This report describes five cases of unusual neurological illnesses occurring after treatment with fludarabine. These suggest that caution should be exercised in patients receiving fludarabine who develop neurological abnormalities, with prompt investigation and if necessary cessation of the drug.

Adult↗
PubMed1994

Polymeric nutrition as the primary therapy in children with small bowel Crohn's disease.

BACKGROUND: Recent studies in adults have shown that polymeric (whole protein) diets are as effective as semi-elemental and elemental formulae for the induction of remission in small bowel Crohn's disease. Whole protein diets are more palatable and cheaper. There have been no studies confirming efficacy in children. PATIENTS AND METHODS: We report our experience with seven children with active small bowel Crohn's disease given a casein-based, polymeric feed rich in TGF-beta 2 (Specific Polymeric Diet; Nestle-Clintec; Vevey, Switzerland) as complete nutrition for 8 weeks. RESULTS: Initial and follow-up assessments were performed. All children showed a significant improvement in disease activity, with C-reactive protein returning to normal, an increase in serum albumin and a good weight gain. Initial and follow-up ileal biopsies were assessed and showed reduced mucosal inflammation in six of seven children, with complete healing in two. CONCLUSION: In an uncontrolled descriptive study we have shown that a polymeric (whole protein) diet is a therapeutic option for small bowel Crohn's disease in children. By comprehensive follow-up we have demonstrated clinical and biochemical remission, with an improved endoscopic appearance and a reduction of mucosal inflammation in the terminal ileum.

Adolescent↗
PubMed1994

Characterization of beta-glucosidase activity in yeasts of oenological origin.

Three hundred and seventeen strains representing 20 species of yeasts were screened for the presence of beta-glucosidase activity. All of the strains of the species Debaryomyces castellii, Deb. hansenii, Deb. polymorphus, Kloeckera apiculata and Hansenula anomala showed beta-glucosidase activity, but only one of 153 strains of Saccharomyces cerevisiae. The other species behaved differently, depending upon the strain. The strains that hydrolysed arbutin were checked to localize the beta-glucosidase activity. A strain of Deb. hansenii exhibited the highest exocellular activity and some wall-bound and intracellular activity. The beta-glucosidase synthesis from this yeast was enhanced by aerobic conditions of growth, was repressed by high glucose concentration (9%) and occurred during exponential growth. The optimum conditions for enzymatic preparations of Deb. hansenii were between pH 4.0 and 5.0 and 40 degrees C. A high concentration of ethanol and glucose did not reduce the enzymatic activity. The enzymatic preparations of Deb. hansenii released monoterpenols and other alcohols from a grape glycoside extract.

Arbutin↗
PubMed1994

Cyclosporin as initial treatment for Crohn's disease.

Childhood Crohn's disease may cause significant morbidity. T cell activation is considered to be central to Crohn's disease pathology, and as cyclosporin is a powerful inhibitor of T cell activation, and has been used in adult Crohn's disease with encouraging results, it may offer the prospect of remission if given early in the course of disease. Children with newly diagnosed Crohn's disease or those relapsing off treatment were therefore given cyclosporin or conventional treatment (enteral nutrition or corticosteroids) by random allocation. Evaluation was performed initially and at two months. Twenty four children were studied (10 on cyclosporin and 14 on conventional treatment; one child on cyclosporin withdrew). Significant clinical improvement occurred in the group on conventional treatment, but not in the cyclosporin group. Colonoscopic improvement was noted in 5/9 on cyclosporin and 8/14 on conventional treatment, but neither group produced a significant fall in median colonoscopic index. Histological improvement was seen in 7/8 on cyclosporin and 8/13 on conventional treatment, but cyclosporin was not significantly better. Cyclosporin produced improved clinical and histological appearance without matched improvement in blood disease indices. It was not better than conventional treatment, and simple oral administration is probably not suitable for newly diagnosed patients with Crohn's disease.

Adolescent↗
PubMed1993

Primary lymphoma of the small intestine. A clinicopathological study of 119 cases.

Small bowel lymphomas account for 20 to 40% of primary gut lymphomas in Western populations and are among the most common malignant tumours of the small bowel. We studied 119 cases of primary small bowel lymphoma presenting over 4 decades. Two thirds of the patients were men with a peak age incidence in the 7th decade. Common presenting features included abdominal pain, weight loss, small bowel obstruction, and acute abdomen. Tumours were classified using the Kiel European Association for Haematopathology Geneva Workshop scheme and phenotyped on paraffin sections; 66% were B cells, and 34% were T cell. In all cases, the antibodies L26 and polyclonal CD3 reliably distinguished between B- and T-cell tumours. Of the B-cell lymphomas, 62% were diffuse high grade, 20% were low-grade lymphomas of mucosa-associated lymphoid tissue, 11% had both low- and high-grade components, and 7% were other low-grade types. Of the T-cell lymphomas, 83% were high grade, and 49% were enteropathy associated. Most T-cell lymphomas were ulcerated plaques or strictures in the proximal small bowel; B-cell lymphomas tended to be annular or polypoid masses in the distal and terminal ileum. Survival data showed that low-grade B-cell lymphomas had the best outcome and T-cell lymphomas the worst. Adverse prognostic features included perforation, high-grade histology, multiple tumours and advanced stage.

Adolescent↗