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E Kouroumalis

Publications and source records attributed to E Kouroumalis.

8 recordsLinked to original sources

Current prevalence of hepatitis A, B and C in a well-defined area in rural Crete, Greece.

A seroepidemiological study was carried out in a geographically well-defined area in rural Crete in order to determine the prevalence of A, B and C hepatitis markers in the local population. Serum samples were obtained from 257 subjects (94 males, 163 females), aged 15 years and over, who visited the primary health care services of the Spili Health Centre between July 1993 and March 1994, and from 164 subjects (83 males, 81 females) randomly selected from households in three neighbouring villages of the study area. In samples obtained from the Spili Health Centre, antibodies to hepatitis A virus (anti-HAV) were detected in 234/244 (95.9%) subjects, antibodies to hepatitis B virus core antigen (HBcAb) were detected in 63/257 (24.5%) subjects and antibodies to hepatitis C virus (anti-HCV) were detected in 28/257 (10.9%) subjects. The corresponding figures for those randomly selected from the villages were 135/154 (87.7%), 16/164 (9.8%) and 5/164 (3%) respectively. Hepatitis B surface antigen (HBsAg) was positive in three (1.2%) subjects from the first group, while none of those recruited from the villages were positive for HBsAg. Interestingly, hepatitis markers were closely associated with age. No subjects under the age of 15 years showed evidence of prior hepatitis A infection and approximately 20% of those between 15 and 44 years of age were also negative. By contrast, practically all subjects older than 44 years were anti-HAV positive. Similarly, the majority of all those who were anti-HCV positive were older subjects. Seroepidemiology of hepatitis in this well-defined population seems to be different from other parts of Greece, at least for hepatitis B and C viruses. There is a very low prevalence of HBsAg and a very high incidence of anti-HCV. Low exposure to HAV, as found in other parts of the country, was also found in the younger generation in this rural area of Crete.

Adolescent

Ulcerative colitis is as common in Crete as in northern Europe: a 5-year prospective study.

OBJECTIVE: To study the incidence of ulcerative colitis and to analyse the pattern of the disease in the prefecture of Heraklion, Crete. PARTICIPANTS: The population at risk comprised 263,670 inhabitants in the prefecture of Heraklion (2641 km2). The two regional hospitals, five health centres, 109 private family doctors and 145 specialists participated in the study. METHODS: A prospective and population-based epidemiological study of ulcerative colitis over five years from 1990 to the end of 1994. RESULTS: Overall, 117 patients with ulcerative colitis (75 males and 42 females) were newly diagnosed during the study period. The mean annual incidence of the disease for the years 1990-1994 was 8.9 per 10(5) inhabitants (95% CI 7.2-10.4). The male to female ratio was 1.8:1. There were no significant difference between the age-specific incidences of the age groups. The majority (51.3%) of the patients were exsmokers and one-third had never smoked. A family history of first-degree relatives positive for inflammatory bowel disease was obtained in 9.6% of our patients. CONCLUSION: Ulcerative colitis is common in Crete; its incidence is as high as in Northern Europe.

Adolescent

Cholesteryl esters in human gallbladder bile and mucosa.

Cholesteryl esters, identified by thin-layer and gas-liquid chromatography followed by mass spectroscopy in a few cases, were found in all human bile samples analysed. The amount varied extensively both in absolute concentration and when expressed as a percentage of the total cholesterol present. In about 30% of samples, the percentage of ester exceeded 4% of total cholesterol but there was no clear association with the presence of cholesterol gallstones or pigment stones, nor was there any association with the lithogenicity of bile.

Bile

Human gallbladder epithelium: non-specific esterases in cholecystitis.

Esterases active at neutral and acid pH have been demonstrated in human gallbladder epithelium. Reaction to a wide variety of inhibitors and activators suggests that they probably represent the same enzyme with two active sites while a close correlation with acid phosphatase, a known lysosomal enzyme, suggests a lysosomal localization. Esterase activity in the gallbladder mucosa in significantly decreased in chronic cholecystitis. Polyacrylamide gel electrophoresis suggests that cholesterol stones may be associated with a specific type of isoenzyme pattern. Esterase positive cells are present in the inflammatory infiltrate in the lamina propria of the gallbladder in most cases of chronic cholecystitis. Naphthol AS-D chloracetate esterase staining indicates that mast cells form a large part of the infiltrate. Bile acids modulate the enzyme activity in vitro. Although the exact substrate specificity is not known, several possibilities are discussed, implicating esterases in the pathogenesis of chronic cholecystitis.

Acid Phosphatase

Gallbladder epithelial acid hydrolases in human cholecystitis.

The lysosomal enzymes beta-glucuronidase and acid phosphatase were studied in 112 patients with cholecystitis. Acid phosphatase activity was generally lower in patients with cholesterol stones compared with cases with pigment stones. beta-glucuronidase activity was higher in acalculous cholecystitis than in any other group, a fact compatible with the concept that in lithiasis the enzyme is secreted into the bile and therefore may participate in nidus formation. Histochemistry at light microscopical level clearly demonstrates the lysosomal distribution of these enzymes and their presence in the macrophages infiltrating lamina propria in cholesterolosis. Electron histochemistry in 45 patients showed acid phosphatase activity in lysosomes and some in mucous droplets. Thiamine pyrophosphatase activity, a marker for the Golgi system, showed a close association with these mucous droplets. The secretion of mucus will be accompanied by a secretion of acid phosphatase, and by implication other acid hydrolases, into the bile.

Acid Phosphatase

Mucosal alkaline phosphatase and bile lipids in the gallbladder in cholecystitis.

Histochemically, alkaline phosphatase was localised in epithelial brush-border and capillary endothelium of the lamina propria in 41 gallbladders studied. Three distinct patterns of the brush-border enzyme distribution were observed, namely, complete delineation, patchy localisation and a brush-border totally devoid of enzyme activity. Where no histochemical activity was found, biliary chenodeoxycholate was 50 per cent. higher than in cases of patchy distribution and twice as high as in cases with complete staining of the brush-border. Conversely, biliary cholate levels were significantly higher in completely stained cases. Biliary cholesterol was higher in the cases with no histochemical activity and this was reflected in a significantly higher lithogenic index. Significant quantities of cholesterol esters were found in bile from the focal activity group only. Total alkaline phosphatase activity assayed in gallbladders from 112 patients with cholecystitis and/or lithiasis showed that activity was significantly lower in patients with pigment stones than patients with cholecystitis and/or cholesterol stones. This activity was not related to biliary lipid composition in the 77 bile samples analysed. This evidence indicates that biliary lipid composition is associated with the histochemical distribution of alkaline phosphatase in gallbladder mucosa.

Alkaline Phosphatase

The cholesterol/dry weight ratio: a simple substitute for lithogenic index.

The limiting solubility of cholesterol in bile has been defined by several lithogenic indices which all require determination of phospholipids, cholesterol, and bile salt concentrations. These technically demanding assays are not widely available and restrict general application of lithogenic index studies while the indices in use do not accommodate differences in water content of bile. Consequently, a simple index that requires only measurement of biliary cholesterol concentration and bile dry weight has been assessed by comparison with a commonly used lithogenic index. This simple index correlates well with the conventional sophisticated lithogenic index and is not influenced by use of bile obtained by direct aspiration or by duodenal drainage. Similarly, division into patient groups based on various clinical parameters does not influence the correlation. This simple index will allow routine laboratories to assess bile lithogenicity.

Bile

Cholecystitis: a fine structural analysis.

The epithelial cells from 40 gallbladders showing chronic cholecystitis and five with cholesterolosis were examined by electron microscopy. A number of features of non-specific cytological injury were noted some of which may have been related to the disease and others to anoxia. The basement membrane showed reduplication. Intraepithelial cells were identified as lymphocytes, polymorphonuclear leukocytes, macrophages and mast cells. Lipid droplets in the epithelial cells were found in 60 per cent. of the specimens.

Basement Membrane