Bone mineral content and density in asymptomatic children with coeliac disease on a gluten-free diet

OBJECTIVES

Osteoporosis is a complication of coeliac disease. A gluten-free diet improves but does not normalize bone mineral density in adult patients. Only limited data are available regarding the influence of the disease and diet on bone mineralization in children. The aim of this study was to evaluate the radial bone mineral content and density in children and adolescents who are asymptomatic on a gluten-free diet.

SUBJECTS AND METHODS

The bone mineral content (BMC) and density (BMD) values of the non-dominant radius midshaft in 91 children (53 girls, 38 boys, mean age 11.7 years, mean duration of disease 8.7 years) were determined by single-photon absorptiometry. At the diagnosis and at least three years after commencement of a gluten-free diet, serum calcium, phosphorus, albumin concentrations and alkaline phosphatase activities were measured in all patients, and intact parathormone concentrations in 16 patients.

RESULTS

The mean BMC Z-score value in the female adolescent group only was significantly lower than normal (mean Z-score -1.04, P < 0.01). In contrast, the mean BMD Z-score was significantly higher compared to a healthy population both in girls (mean Z-score +1.36, P < 0.001) and in boys (mean Z-score +0.53, P < 0.02), as well as in the total patient group (mean Z-score +1.01, P < 0.001). The radial diameter was significantly smaller than normal in both pre-pubertal and adolescent groups. Serum laboratory parameters of asymptomatic patients were in the normal range. The parathormone mean value was significantly lower after at least three years of gluten-free diet than at diagnosis (mean +/- SD 3.77 +/- 1.07 versus 7.89 +/- 2.54 pmol/l, P < 0.01), but significantly higher compared to controls (2.89 +/- 0.90 pmol/l, P < 0.05).

CONCLUSIONS

These data indicate that treated, asymptomatic coeliac children and adolescents have normal or even higher radius mineral density values than controls, but the bone size remains reduced. Although there is no direct evidence of calcium malabsorption in this cohort of coeliac patients, the slightly higher parathormone levels, together with some other factors, particularly delayed puberty, may result in reduced bone size.

[Determination of cagA, vacA genotypes of Helicobacter pylori with real-time PCR-method]

Presence of cagA gene of Helicobacter pylori (H. pylori) increases proliferation of stomach mucosa and it is an index of raised virulence of the bacteria. The vacA gene of H. pylori induces a serious inflammation of stomach. The purpose of this study was to determine cagA and vacA genotypes of H. pylori using real-time polymerase chain reaction (PCR) method with the double strain DNA-(dsDNA) binding SYBR Green I. dye. Results were compared with those of two immunohistochemical methods. 43 patients' paraffin embedded biopsy tissue samples were examined by histology, epidermal growth factor receptor (EGFR), proliferating cell nuclear antigen (PCNA) immunohistochemistry and melting curve analysis of real-time PCR using LightCycler instrument. Results of histology and real-time PCR from gastric biopsies correlated in 57% of cag acases and in 58% of vac cases. Significant difference was detected between normal and gastritis cases in the presence of cagA gene (p = 0.003) and between normal epithelial and intestinal metaplasia cases in the presence of vacA gene (p = 0.045) by investigation of association of histology and genotype of bacterium. Statistically significant difference (p = 0.02) was found between increased cell proliferation and the presence of gastritis. Significant correlation was found between the presence of cagA gene and EGFR expression in intestinal metaplasia cases (p = 0.0418). Results underlie the statistics that infection with cagA positive H. pylori strain increases the cell proliferation on the stomach mucosa and raises the chance of development of intestinal metaplasia. Infection with vacA positive H. pylori inhibits the signal-transduction pathway of EGFR, which influences mechanisms of mucosa repair. The role of EGFR and H. pylori infection is yet unclear in intestinal metaplasia and cancer. The authors' method seem to be suitable for determination of genotypes of H. pylori.

Determination of Helicobacter pylori cagA, vacA genotypes with real-time PCR melting curve analysis

OBJECTIVES

genotypes of Helicobacter pylori are the focus of interest because they play a prominent role in mucosal injury. The purpose of this study was to determine cagA and vacA genotypes of H. pylori using real-time polymerase chain reaction (PCR) method with a double strain DNA binding SYBR Green I.dye, and to compare this with those of two immunohistochemical methods.

METHODS

forty-three paraffin-embedded biopsy tissue samples were examined by histology, epidermal growth factor receptor (EGFR), proliferating cell nuclear antigen (PCNA) immunohistochemistry and melting curve analysis of real-time PCR.

RESULTS

the presence of cagA gene was associated with a significantly higher frequency of gastritis (P=0.003) than that of vacA gene with intestinal metaplasia (P=0.045). Significant difference was found between the presence of cagA gene and EGFR expression in intestinal metaplasia cases in comparison with cagA negative samples (P=0.0418). Statistically significant difference was detected between increased cell proliferation and the presence of gastritis.

CONCLUSIONS

this method seems to be suitable for H. pylori genotype determination. Sensitivity, speed and simplicity are key areas in the development of PCR assays for H. pylori. Results supported the notion that infection with cagA positive H. pylori strain causes more augmentated cell proliferation in the stomach mucosa.

Effect of Helicobacter pylori infection and eradication on gastric epithelial cell proliferation and apoptosis

OBJECTIVES

the effect of Helicobacter pylori infection on gastric epithelial cell proliferation and apoptosis is still controversial. Our aim was to evaluate the effect of H. pylori infection on cell kinetic parameters in normal gastric epithelium, gastritis with/without intestinal metaplasia and gastric cancer.

PATIENTS AND METHODS

antral biopsies were taken from 121 patients (61 women, 60 men, mean age 58.5+/-14.3 years of age) who underwent routine gastroscopy for upper gastrointestinal symptoms. Sections were scored for normal epithelia (n=15), gastritis without intestinal metaplasia (n=74), gastritis with intestinal metaplasia (n=24), and gastric adenocarcinoma (n=8). Fifty-two patients had H. pylori positive gastritis, and success of H. pylori eradication therapy was controlled in 12 cases, all with intestinal metaplasia. To characterize cell proliferation and assess apoptosis, immunohistochemistry [Proliferating Cell Nuclear Antigen (PCNA)], histochemistry [Argyrophil Nucleolar Organizer Regions (AgNOR)], and terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridinetriphosphate (dUTP) nick end-labeling (TUNEL) were used, respectively.

RESULTS

both cell proliferation and apoptosis is was higher in chronic gastritis when compared with normal epithelia, but neither PCNA LI (54.79+/-19.1 vs. 53.20+/-20.7) nor AgNOR counts (291.43+/-44.3 vs. 277.8+/-57.54) were different in H. pylori positive versus negative chronic gastritis. A significant positive correlation (P<0.05) was found in this group between PCNA and AgNOR techniques. Apoptosis was significantly higher (P<0.05) in H. pylori positive cases only when intestinal metaplasia was not present. Cell proliferation in intestinal metaplasia decreased to the activity of normal epithelium after successful eradication of H. pylori but remained high if eradication therapy failed.

CONCLUSIONS

epithelial cell proliferation does not depend on H. pylori status in chronic gastritis. H. pylori increases apoptosis only in the absence of intestinal metaplasia.

[Effect of Helicobacter pylori infection and eradication on proliferative kinetics of the gastric mucosa]

Helicobacter pylori infection is associated with an increased cell proliferation activity, however the exact mechanisms have not been elucidated. Our aim was to study the effect of Helicobacter pylori infection on normal gastric epithelia, gastritis, intestinal metaplasia and carcinoma by the expression of proliferating cell nuclear antigen and nucleolus organizer regions. Antral biopsies were taken from 121 patients (61 women, 60 men; mean age 58.5 y.). Sections were scored for normal epithelia (n = 15), gastritis without intestinal metaplasia (n = 74), gastritis with intestinal metaplasia (n = 24) and gastric carcinoma (n = 8). 52 patients had H. pylori positive gastritis, and success of eradication therapy was controlled in 34 cases. To characterize cell proliferation immunohistochemistry (PCNA) and histochemistry methods (AgNOR) were used. Results of PCNA and AgNOR significantly correlated except of that in the intestinal metaplasia group. PCNA LI and AgNOR counts were not significant higher in H. pylori positive compared to the H. pylori negative gastritis. Presence of H. pylori caused higher proliferation rate in intestinal metaplasia group measured by PCNA. In the group of intestinal metaplasia the proliferation activity decreased to the activity of the normal epithelia after the successful eradication, but remained high if eradication therapy was failed. Our results suggest, that H. pylori infection plays only as a co-factor in gastric carcinogenesis. Results were controversial in the intestinal metaplasia group, that can be explained by the heterogeneity of the bacteria.

[Celiac disease today: review of the growing knowledge]

Coeliac disease is the most common disorder with malabsorption of the small intestine, caused by the gluten fraction of cereals in genetically predisposed individuals. T-cell mediated autoimmune processes are initiated by gluten exposure, leading to both intestinal and extraintestinal manifestations, therefore coeliac disease is nowadays considered to be a systemic disorder. More and more diseases are proved to be associated with coeliac disease, in these conditions screening is strongly recommended. The studying of the recently explored autoantibodies against tissue transglutaminase brought us further in the understanding of the pathophysiology of coeliac disease. The spreading of reliable serologic methods modified our knowledge on the clinical picture and prevalence of the disease. In case of long-term dietary abuse the most common complications are decreased bone mineral density and development of lymphomas. Sustained glutenfree diet results in clinical and histological restitution, affects the course of associating diseases beneficially and decreases the risk for malignancies.

[Molecular biology characteristics of Helicobacter pylori]

Attention has been recently adverted to the Helicobacter pylori (H. pylori) by the fact, that its association with occurrence of gastroduodenal ulcer and gastric carcinoma had been justified. Our current understanding about metabolism and physiology of it is still not full, however, great strides have been made as for the methods of investigation during the last 16 years. Complete genome sequence of pathogenic strain of the bacteria have recently became identified, by which certain fundamental aspects of biology of H. pylori have been highlighted. Based on data, infection may presumably act as a cofactor to the development of peptic ulcer disease and carcinogenesis, however, details of pathomechanism are still unclear. Variability and genotype of bacteria, immune reactions and genetic patterns of host organism and mechanisms sustaining the balance of mucosal integrity may have additional influence. This study provides an overview on the current understanding about molecular biology of H. pylori.

Determination of H+/K+-ATPase activity in human gastric biopsy specimens

The aim of our work was to develop a method to determine the the H+/K+-ATPase activity of human gastric biopsy samples. Our method is based on the phosphatase activity and the K+-inducible property of the enzyme. K+-inducible pNPPase activity was determined from homogenated corpus and antrum biopsy samples. H+/K+-ase activity was calculated as the difference between the corpus and antrum K+-inducible pNPPase activities. Quality control measurements were done during 20 successive days from pooled homogenates. The total, between-day and between-run, within-day and within-run coefficients of variations were between 10 and 16%. The healthy mean and reference range of K+-inducible pNPPase activity in the corpus was 95.8 (95% CI: 83.4-108.2 mU/mg protein); in the antrum it was 28.3 (21.6-35.0) mU/mg protein. The calculated H+/K+-ATPase activity was 67.2 (56.9-77.5) mU/mg protein. The measured activities were independent of the age and gender. Summarizing our results we have concluded, that our novel method might be a potential tool to gather data about the functional acid producing capability of human gastric mucosa.

[Hepatocyte proliferation and DNA content in chronic hepatitis C]

Apart from inflammatory reaction, the death of hepatocytes is also a characteristic of chronic hepatitis. Necroinflammation is followed by compensatory proliferation, which plays a rather important role in maintaining the liver function. Authors studied the DNA content of hepatocytes in patients with chronic hepatitis C, and determined the ratio of hepatocytes in phases G1, S and G2 to determine the hepatocyte proliferation and regeneration capacity of the liver. Liver biopsy samples were taken from 23 patients with chronic hepatitis C and from 16 with chronic hepatitis with non viral origin, from which nuclear suspension counts were done based on the histological slides. A total of 16 normal liver tissue samples served as control. The DNA index, G1, S, G2 and polyploid fraction were determined using the DNACE (Digital Image Analyzer for Nuclear Deoxyribonucleic Acid Content Estimation, KFKI/NIO, Hungary) digital imaging process. The DNA index was found to be significantly higher in the chronic hepatitis C than in the non-C group, with the verification of aneuploidy (DI > 1.10). The chronic non-C hepatitis cases showed lower G1 (88 +/- 6) and higher S (7.8 +/- 6.6) fractions. In comparison to the normal liver tissues, the chronic hepatitis C cases also revealed a significantly (p < 0.05) lower G1 (91 +/- 5) and a higher S (5.4 +/- 3.6) fraction, though staying behind the values found for the non-viral group. The deviation can be explained by the presentation of the HCV proliferation inhibitory effect. The polyploid cell fraction revealed a significantly higher value in the chronic non-viral cases as compared to the C virus group, reflecting on the decreased regeneration capacity of the liver. When comparing the HCV groups, significant differences were found between the mild and moderate cases in respect to the G1 and G2 fractions. At the same time, the moderate and severe cases showed statistical deviation regarding the DNA index. Chronic hepatitis C virus infection reduces the proliferation of hepatocytes and the regeneration capacity of the liver. The aneuploid DNA index reflects on genetic instability, which could be the basis of the malignant transformation of the cells.

Effect of hepatitis C virus on hepatocyte proliferation and DNA ploidy in patients with chronic hepatitis C

Hepatitis C virus infection may act as a cofactor by inducing chronic hepatitis and cirrhosis, playing a promoting role in the multistep process of hepatocarcinogenesis by maintaining liver inflammation, hepatocyte necrosis and regeneration. The aim of this study was to measure the DNA ploidy and cell proliferation of hepatocytes in patients with chronic hepatitis C. Hepatocyte nucleus suspension was analyzed from 45 patients with chronic hepatitis C and from 27 patients with chronic hepatitis non-C. The histopathological pattern of chronic hepatitis samples/grade, stage/was investigated. A significantly lower cyclin A protein expression and cytometrically measured S-phase fraction was observed in chronic hepatitis C as compared to chronic hepatitis non-C, representing suppressed cell proliferation of virus infected cells. In the chronic hepatitis C groups, the S-phase fraction depression was moderate, the grade of inflammation and cyclin A protein expression were also decreased, mainly in the severe grade group. In chronic hepatitis non-C, the number of cyclin A staining-positive cells increased parallel with severity of the inflammation. In addition, the HCV infection caused a near diploid minimally aneuploid cellular DNA content in the cases of moderate and severe histological groups. In contrast, the cellular DNA content was consequently diploid-independent of histological grades in chronic hepatitis non-C. Our results suggest that in chronic viral hepatitis C, the hepatocyte proliferation is suppressed parallel with the degree of inflammation, while the DNA content becomes aneuploid. The aneuploidy is a sign of genetic instability, predisposing the affected cells to unbalanced chromosomal abnormality which finally leads to malignant transformation.

Circulating plasma endothelin-1, plasma lipids and complications in Type 1 diabetes mellitus

The damage of endothelial integrity is an important step in the atherogenic process. To evaluate the role of circulating endothelin-1 (ET-1) in Type 1 diabetes mellitus (T1DM), plasma ET-1 levels were evaluated in T1DM patients either with (n=9) or without hyperlipidaemia (n=11), or with (n=9) and without (n=11) late diabetic complications, in non-diabetic hyperlipidaemic patients (n=17) and in healthy volunteers. Groups were matched for age, sex and body mass index.

RESULTS

Serum total cholesterol and apolipoprotein B were significantly higher in the diabetic group (p<0.05). Plasma ET-1 level was similar in controls and in non-diabetic hyperlipidaemic subjects (5.77+/-1.74 ng/l vs 4.97+/-1.58 ng/l); however, diabetic hyperlipidaemic patients had a significantly higher plasma ET-1 concentration compared to control subjects (6.67+/-2.44 ng/l vs 4.97+/-1.58 ng/l, p<0.05). Diabetic patients with vascular complications had a significantly higher plasma ET-1 concentration than found in diabetic patients without complications (6.99+/-2.17 ng/l vs 4.74+/-1.27 ng/l, p<0.01) and in controls (6.99+/-2.17 ng/l vs 4.97+/ 1.58 ng/l, p<0.01). Patients with diabetic complications also had a significantly higher apolipoprotein B level compared to healthy controls (0.94+/-0.37 g/l vs 0.66+/-0.12 g/l, p<0.005).

CONCLUSION

The susceptibility of T1DM patients to the development of atherosclerosis might be attributed to the relationship between elevated lipid levels and ET-1.

[Activity of neutral endopeptidase in serum of patients with primary biliary cirrhosis]

Neutral endopeptidase (neprilysin; EC 3.4.24.11) is present in the brush border membrane, for example in the bile ducts. We investigated serum neprilysin activity and its correlation with cholestatic markers in patients with primary biliary cirrhosis. Sera of 39 patients with primary biliary cirrhosis (37 females, 2 males, mean age 45 years, range 24-71 years) were investigated. Twenty-seven healthy volunteer subjects served as control. Serum neprilysin activity was measured by a sensitive microplate-based continuous monitoring kinetic assay. Succinyl-alanyl-alanyl-phenyl-alanyl-4- nitroanilide was used as substrate. For statistical analysis Kruskal-Wallis ANOVA by ranks and Mann-Whitney U test were used. The neprilysin activities were significantly higher in stages III (mean 13.2 +/- SD 10.8 U/l) and IV (21.8 +/- 17.5) than in the control subjects (2.4 +/- 2.9, p < 0.01). There was no significant difference in neprilysin activity between the patients with stages I and II, or between stage I + II (2.88 +/- 3.0) and the control. Positive correlation was found between the activity of neprilysin and serum bilirubin, alkaline-phosphatase and gamma-glutamyl-transferase (p < 0.005 for each). In this study we confirmed that serum neprilysin activity is elevated in patients with primary biliary cirrhosis at advanced stages and the elevation correlated with the cholestatic markers. The increased neprilysin activity seems to be an indicator for the severity and progression of the disease.

[Comparison of various methods in the detection of Helicobacter pylori infection]

There are several possible methods to detect H. pylori in the gastric mucosa. The aim of our prospective study was to evaluate the diagnostic value of these tests and to define their place in the clinical practice. 109 (45 male, 64 female) patients who underwent upper GI endoscopy were included. Before endoscopy, whole blood was collected for serological test and 13C-UBT (13C-urea breath test) was performed. During endoscopy, multiple biopsies were collected from the antrum and corpus for the examination of H. pylori status by histology and rapid urease test. Patients with positive histology and a positive result of any other examinations, or--in case of negative histology--with two positive results of the remaining examinations were considered to be H. pylori-positive. 50 patients (46%) proved to be H. pylori-positive. Sensitivity and specificity, respectively, were as follows [in brackets: negative predictive value (NPV) and positive predictive value (PPV), respectively]: histology, 98% and 92% (98% and 91%); 13C-UBT, 93% and 98% (94% and 98%); rapid urease test, 83% and 100% (86% and 100%); serological examination, 86% and 74% (88% and 70%). The sensitivity and the clinical role of the methods used for the detection of H, pylori infection is different. Histology is the most reliable method if endoscopy in performed. The positive result of the rapid urease test is also of good diagnostic value. The 13C-UBT is the method of choice if no endoscopy is performed and the clarification of H. pylori status is necessary. This method can be useful to control the success of bacterium eradication as well. The serological examination provides instant result, therefore this method is proposed for screening and epidemiological studies.

[Detection of aneuploidy from gastrointestinal biopsy samples]

Aim of the present work was the development of a mechanic cell separation protocol for gastrointestinal biopsy analysis. Evaluation of the technique was performed on selected group of patients who underwent routine endoscopy. Routine gastrointestinal biopsies were obtained after informed consent. 23 gastric (6 healthy, 14 gastritis, 3 adenocarcinoma) and 15 colon samples (5 healthy, 7 colitis ulcerosa, 3 adenocarcinoma) were evaluated. The mechanic disruption of the biopsies was performed by Medimachine (DAKO, Denmark), a commercially available system using a 30 microns miner and a 30 microns mesh. The cell solution was centrifuged for 5 minutes by 250 g. The cells were fixed in paraformaldehide and stained by propidium iodide. The flow cytometry analysis was performed on a BD FacStar Plus flow cytometer. The DNA data were evaluated using the Winlist software. All of the preparations were appropriate for flow cytometric analysis. The coefficient of variation of the DNA histograms (n = 7) (CV mean +/- SD. 6.45% +/- 1.21) were acceptable for analysis. In the gastric biopsy samples aneuploidy was determined only in malignant cases. In four of the seven colitis ulcerosa samples and in one of the three adenocarcinoma aneploidy was found. The histologically healthy specimen were all diploid. Mechanic cell separation and disaggregation is a useful method for preparing fresh biopsy specimen for flow cytometry.

[An adult form of type-I. Gaucher's disease]

A young woman with no previous history of any diseases was admitted for further evaluation of a mild thrombocytopenia she has had for some months. No signs of bleeding have so far occurred. Physical examination was normal except for a moderately enlarged spleen. Routine investigations showed lower platelet count. There was no laboratory evidence of disease conditions with autoimmune/inflammatory or hematologic origin. Bone marrow aspirate indicated Gaucher's-like cells raising the suspicion of Gaucher's disease. This was further supported by electron microscopic demonstration of Gaucher's bodies (with the characteristic tubular structures) in crista biopsy specimens. However, definitive diagnosis was obtained by verifying deficient lysosomal glucosylceramide-beta-D-glucosidase activity in peripheral blood leukocytes. Upon the absence of neurologic involvement the patient was typical for the adult form or type-1 Gaucher's disease.

Proteases in gastrointestinal neoplastic diseases

Cysteine and serine proteases are involved in cancer invasion and metastasis. In the past few years we investigated the tissue levels of these proteases in gastric cancer (GC), gastric precancerous changes (CAG), colorectal cancer (CRC) and the plasma and serum levels of proteases in several gastrointestinal tumours, using ELISA methods. Significantly higher antigen levels were found not only in GC tissue but also in CAG with respect to the levels found normal tissue; with respect to CAG, patients with dysplasia had higher levels than patients without dysplasia. The same findings were obtained in CRC. In general protease levels correlated with the major histomorphological parameters, such as grading and histotype in GC as well as in CRC. Tissue protease levels had a strong prognostic impact in GC, in which UPA was singled out by multivariate analysis as the major prognostic factor, and CRC. The plasma levels of urokinase-type plasminogen activator (UPA) and the serum levels of cathepsin B were significantly increased in patients with gastrointestinal tumours. In conclusions, cysteine and serine proteases may have a part not only in GC and CRC invasion and metastasis, but also in the progression of gastric precancerous changes into cancer. They are strong prognostic factors in GC and CRC. These proteases may also have a role as tumour markers in the early diagnosis of gastrointestinal tract tumours.

[Glucocorticoid-induced osteoporosis]

Chronic glucocorticoid treatment is the most frequent cause of secondary osteoporosis. The direct inhibitory effect of glucocorticoids on osteoblasts results in decreased bone formation. Increased osteoclastic bone resorption due to low concentrations of gonadal steroid hormones and glucocorticoid-induced direct suppression of intestinal calcium absorption also contribute to the decrease of bone mass in these patients. Bone loss is rapid, particularly in the first months of glucocorticoid therapy. Bone mineral density of the lumbar spine and proximal femur should be measured in patients who are starting chronic therapy with glucocorticoids. Although glucocorticoid-induced osteoporosis is a severe and nowadays partially preventable disorder, osteoporosis prophylaxis is only rarely prescribed to these patients. Recent randomized, controlled trials proved the therapeutic effects of hormone replacement therapy, as well as of bisphosphonates and active vitamin D analogs in primary and secondary prevention of glucocorticoid-induced osteoporosis.

Quantitative DNA and morphometric analysis of gastroscopic brush smears by TV image analysis

OBJECTIVES

To determine quantitative nuclear morpho-and densitometric classifiers and classification techniques for analysis of gastric, Feulgen-stained brush smears.

DESIGN

TV image analysis-based quantitative DNA and morphometric analysis of gastric brush smears in a prospective study.

PATIENTS AND METHODS

Ninety-eight (11 normal, 77 gastritis (17 with intestinal metaplasia) and 10 adenocarcinoma) Feulgen-Schiff-stained gastric brush smears were analysed by TV image analysis. The classification of the smears was based on parallel histological examination. For standards, DNA content of lymphocyte cell cultures was determined by the image and by flow cytometry. From every nucleus, six morphometric (surface, layers, minimum diameter, maximum diameter, perimeter and form factor) and six densitometric (integrated optical density (IOD), average density, sigma density, minimum and maximum density and density range) parameters were simultaneously determined. The smear parameters (object cells CV, DNA index, 2c deviation index, 5c exceeding rate, G1 -S-G2 ratio) were analysed together with the mean and SD values of the nuclear parameters by discriminant analysis and back-propagation neural networks.

RESULT

The normal smears were all diploid and their S + G2 ratio was 15.24+/-7.75% (mean +/- SD). The gastritis smears were all diploid with a proliferation fraction of 20.89+/-6.75%. The tumours were aneuploid in eight of the ten cases with 5c exceeding rate > 6.23%, the S + G2 fraction ratio was 34.72+/-10.12%. The mean nuclear surface area was 46+/-20, 58+/-20 and 74+/-22 microm2 in normal, gastritis and malignant groups, respectively. Significant differences (P<0.05) were found in nuclear surface, minimum and maximum diameter, and perimeter parameters. Using linear discriminant analysis, 100% of the non-malignant cases and 70% of the tumour cases were correctly classified. Using 30 non-malignant and five malignant cases as a training set, the neural networks classified 95% of the remaining cases correctly. The DNA index increased significantly (P<0.05) in Helicobacter pylori-positive cases compared to the negative ones. In gastritis with intestinal metaplasia, the proliferation ratio decreased significantly (P<0.05).

CONCLUSIONS

The image analysis is a useful tool for quantitative gastric cytology. The combination of nuclear morphometric parameters and neural network classifiers with multivariate quantitative DNA analysis is suggested for gastric brush smear quantitative cytology analysis.

Development of a speech-based dialogue system for report dictation and machine control in the endoscopic laboratory

BACKGROUND AND STUDY AIMS

Reporting and machine control based on speech technology can enhance work efficiency in the gastrointestinal endoscopy laboratory.

MATERIALS AND METHODS

The status and activation of endoscopy laboratory equipment were described as a multivariate parameter and function system. Speech recognition, text evaluation and action definition engines were installed. Special programs were developed for the grammatical analysis of command sentences, and a rule-based expert system for the definition of machine answers. A speech backup engine provides feedback to the user. Techniques were applied based on the "Hidden Markov" model of discrete word, user-independent speech recognition and on phoneme-based speech synthesis. Speech samples were collected from three male low-tone investigators.

RESULTS

The dictation module and machine control modules were incorporated in a personal computer (PC) simulation program. Altogether 100 unidentified patient records were analyzed. The sentences were grouped according to keywords, which indicate the main topics of a gastrointestinal endoscopy report. They were: "endoscope", "esophagus", "cardia", "fundus", "corpus", "antrum", "pylorus", "bulbus", and "postbulbar section", in addition to the major pathological findings: "erosion", "ulceration", and "malignancy". "Biopsy" and "diagnosis" were also included. We implemented wireless speech communication control commands for equipment including an endoscopy unit, video, monitor, printer, and PC. The recognition rate was 95%.

CONCLUSIONS

Speech technology may soon become an integrated part of our daily routine in the endoscopy laboratory. A central speech and laboratory computer could be the most efficient alternative to having separate speech recognition units in all items of equipment.

Evidence of in vivo peroxynitrite formation in patients with colorectal carcinoma, higher plasma nitrate/nitrite levels, and lower protection against oxygen free radicals

Endogenously formed nitrogen and oxygen free radicals are believed to be involved in human cancer etiology. Plasma nitrate/nitrite originates from endogenous nitric oxide production in fasting humans, decrease in superoxide scavenger activity (SSA), and free sulfhydryl groups (SH) reflects the amount of superoxide anion generated, and nitrotyrosine is believed to be formed by the interaction of tyrosine and peroxynitrite in vivo. The aim of the current study was to measure plasma nitrate/ nitrite, SSA, and SH in 69 patients (mean age +/- standard deviation, 66 +/- 11 years) with colorectal carcinoma. Nitrotyrosine was measured from both the plasma and tumor tissues in 32 patients. All patients had adenocarcinoma of the colon or rectum. Twenty-five patients were classified as stage B according to Dukes classification as modified by Astler-Coller, 13 were classified as stage C, and 31 patients were classified as stage D. To determine whether the changes are specific for colorectal cancer, 20 patients with active inflammatory bowel disease (IBD; mean age, 52 +/- 18 years) and 30 healthy volunteers, who served as control subjects (mean age, 48 +/- 11 years), were studied. Plasma nitrate/nitrite was measured by the modified Griess method, SSA was measured by an electron/spin resonance spin trapping method, free SH was measured by Ellman's method, and the presence of nitrotyrosine in the plasma and tumor tissue was detected by high performance liquid chromatography (HPLC) using C- 18-derivatized silica (5 microm) column (C18S, Crestpaque, New York, NY, USA) and at a wavelength of 274 nm. Patients with colorectal carcinoma and with active IBD had a significantly higher plasma nitrate/ nitrite level (51.2 +/- 26.2 microm and 56.0 +/- 14.6 microm versus. 29.6 +/- 6.3 microm; p < 0.01), and a lower SSA level (39 +/- 11.5 U/g protein and 52.0 +/- 18.9 U/g protein versus. 88 +/- 25.1 U/g protein; p < 0.05) and SH level (7.7 +/- 3.89 microm protein and 6.4