RESUMEN
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.
Asunto(s)
Apoptosis , Mucosa Gástrica/patología , Mucosa Gástrica/fisiopatología , Infecciones por Helicobacter/patología , Helicobacter pylori , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Ciclo Celular , División Celular , Femenino , Infecciones por Helicobacter/tratamiento farmacológico , Humanos , Intestinos/patología , Masculino , Metaplasia , Persona de Mediana Edad , Neoplasias Gástricas/patologíaRESUMEN
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.
Asunto(s)
Adenocarcinoma/patología , ADN de Neoplasias/análisis , Gastritis/patología , Neoplasias Gástricas/patología , Estómago/citología , Adenocarcinoma/genética , Análisis de Varianza , Biopsia/métodos , Densitometría , Diagnóstico Diferencial , Análisis Discriminante , Citometría de Flujo , Gastritis/genética , Gastroscopía , Humanos , Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Valor Predictivo de las Pruebas , Índice de Severidad de la Enfermedad , Manejo de Especímenes/normas , Neoplasias Gástricas/genética , TelevisiónRESUMEN
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
Asunto(s)
Neoplasias Colorrectales/metabolismo , Nitratos/metabolismo , Oxidantes/metabolismo , Especies Reactivas de Oxígeno , Anciano , Neoplasias Colorrectales/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nitratos/sangre , Nitritos/sangreRESUMEN
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.
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Mucosa Gástrica/microbiología , Mucosa Gástrica/patología , Gastritis/microbiología , Gastritis/patología , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/patología , Helicobacter pylori , Adulto , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , División Celular , Femenino , Mucosa Gástrica/metabolismo , Gastritis/metabolismo , Infecciones por Helicobacter/metabolismo , Infecciones por Helicobacter/microbiología , Humanos , Inmunohistoquímica , Intestinos/microbiología , Intestinos/patología , Cinética , Masculino , Metaplasia , Persona de Mediana Edad , Región Organizadora del Nucléolo/metabolismo , Lesiones Precancerosas/microbiología , Lesiones Precancerosas/patología , Antígeno Nuclear de Célula en Proliferación/análisis , Neoplasias Gástricas/microbiologíaRESUMEN
BACKGROUND: [corrected] Epithelial cell proliferation activity has been reported both to be unaltered and increased in Helicobacter pylori (H. pylori) associated chronic gastritis. The proliferation rate decreased following H. pylori eradication, but results are controversial whether this change is dependent on the success of eradication. We compared the cell proliferation activity of H. pylori positive and negative gastric epithelial biopsies in chronic gastritis with and without intestinal metaplasia (IM) and gastric cancer by the expression of proliferation cell nuclear antigen (PCNA) and Tv image cytometry, and assessed the effect of H. pylori eradication on the cell proliferation rate in the gastric epithelium. METHODS: Brush smears and antral biopsies were taken from 70 patients (42 men, 28 women, mean age 58+/-15 y.o.) on routine endoscopy. Patients were divided into four groups according to the histology; normal epithelia (n = 10), chronic gastritis without IM (n = 24), chronic gastritis with IM (n = 20), and gastric carcinoma (n = 16). Thirty-three patients were H. pylori positive, and success of eradication was controlled in 24 cases. Cell proliferation was measured by immunohistochemistry using PCNA labeling index (LI) and by Tv image cytometry evaluating 12 morpho- and densitometric parameters of each nuclei and 6 additional parameters of each smear. RESULTS: PCNA LI, DNA index and S + G2 ratio were all higher in chronic gastritis than in the normal epithelium, and were further increased in carcinoma. The lower PCNA LI observed in chronic gastritis with IM corresponds to the lower S phase ratio determined by Tv image analysis. In H. pylori positive cases, the proliferation activity was 69.3+/-13.05% prior to the eradication and it decreased to 55.8+/-23.31% after the successful eradication therapy. When immunohistochemistry was compared with Tv image cytometry, PCNA LI significantly correlated with the percentage of cells in GL phase (r = -0.415) and S phase (r = 0.385), Integrated Optical Density mean (r = 0.598), density maximum (r'= 0.608), surface (r = 0.670), layers (r = 0.638), diameter minimum (r = 0.619), diameter maximum (r = 0.730) and perimeter (r = 0.501), respectively (p < 0.05). CONCLUSIONS: Epithelial cell turnover is increased in chronic gastritis with or without IM, and in gastric carcinoma. The lower PCNA LI observed in chronic gastritis with IM corresponds to the lower S phase ratio determined by Tv image analysis. Cell proliferation decreases after successful H. pylori eradication. Both methods proved to be reliable for the determination of epithelial cell proliferation.
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Gastritis/patología , Infecciones por Helicobacter/patología , Neoplasias Gástricas/patología , Adulto , Anciano , División Celular , Enfermedad Crónica , ADN de Neoplasias/análisis , Epitelio/patología , Femenino , Gastritis/tratamiento farmacológico , Gastritis/microbiología , Infecciones por Helicobacter/tratamiento farmacológico , Humanos , Citometría de Imagen , Inmunohistoquímica , Masculino , Metaplasia/patología , Persona de Mediana Edad , Antígeno Nuclear de Célula en Proliferación/análisis , Estómago/patología , Grabación en VideoRESUMEN
Defence against the reactive oxidants produced during aerobic metabolism is a complex process and is provided by a system of enzymes and antioxidant compounds capable of preventing excess radical production, neutralising free radicals and repairing the damage caused by them. Regulation of the antioxidant system must provide sufficient, properly located, antioxidant compounds and enzymes. Damage to this system has been proved to play a role in various disorders. Long-term complications of diabetes mellitus are supposed to be partially mediated by oxidative stress. The authors summarise experimental and clinical investigations in this field and analyse the possible importance of the changes in the antioxidant system in the development of diabetic vascular complications.
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Diabetes Mellitus/enzimología , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Animales , Catalasa/metabolismo , Angiopatías Diabéticas/etiología , Glutatión Peroxidasa/metabolismo , Humanos , Ratas , Superóxido Dismutasa/metabolismoRESUMEN
Merkel cell cancer is a rare carcinoma arising from the neuroendocrin cells of the skin. The diagnosis is based on the clinical behaviour, histopathologic and ultrastructural findings and immunohistochemical results. An unusual case of Merkel cell carcinoma is presented. Mass from the umbiculus and a right inguinal lymph node was excised in a 63-year-old female. The histologic features of a typical, primitive small cell tumor combined with the immunohistochemical evaluations established the diagnosis. Rare polynuclear giant cells were focally present in our case. Patient was treated with combination of chemotherapy (Cisplatin, Etoposid) and radiotherapy. Control examinations showed complete respond. One year later metastasis developed. Resection of all known metastasis were performed. Two months after the laparotomy she died of metastatic disease. The autopsy did not reveal any other primary tumor. The capricious nature of the clinical course and the differences between this tumor and other carcinomas is emphasized.
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Carcinoma de Células de Merkel , Tumores Neuroendocrinos , Neoplasias Cutáneas/diagnóstico , Carcinoma de Células de Merkel/diagnóstico , Carcinoma de Células de Merkel/patología , Carcinoma de Células de Merkel/terapia , Terapia Combinada , Quimioterapia Combinada , Resultado Fatal , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Tumores Neuroendocrinos/diagnóstico , Tumores Neuroendocrinos/patología , Tumores Neuroendocrinos/terapia , Neoplasias Cutáneas/patologíaRESUMEN
The journal Science considered nitric oxide (NO) the molecule of the year 1992. This small, instable, potentially toxic gas freely crosses cell membranes. NO is produced from L-arginine by NO-synthase. The various physiological and pathological effects of NO can be explained by its reactivity and different routes of formation and metabolism. In mammals, at least three isoenzymes of NO-synthase (neuronal, endothelial and inducible forms) are known. NO exerts different effects in acidic, neutral and basic pH conditions, it is cell-protective when produced is small quantities whereas it is toxic when exceeds millimolar concentrations. Both the overproduction and suppression of NO release may have harmful effects. As a neurotransmitter, it plays important role in cell-signaling, in the erection of penis and also in the learning process. When produced by endothelial cells, it is a potent vasodilatator, and phagocytes use NO to kill microorganisms. NO also may play pathological role in chronic inflammations, immune processes and tumour generation. Based an our current knowledge, NO can be used in the therapy of pulmonary hypertension, cerebral ischemia and relaxation disturbances of smooth muscle sphincters, and the blockade of NO synthase activity may help in the management of septic shock, hypotension and inflammations.
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Óxido Nítrico , Animales , Circulación Cerebrovascular/efectos de los fármacos , Humanos , Hipertensión Pulmonar/tratamiento farmacológico , Hipotensión/tratamiento farmacológico , Mamíferos/fisiología , Neurotransmisores/fisiología , Óxido Nítrico/biosíntesis , Óxido Nítrico/farmacología , Óxido Nítrico/fisiología , Óxido Nítrico Sintasa/fisiología , Investigación , Choque Séptico/tratamiento farmacológico , Vasodilatadores/farmacologíaRESUMEN
The authors review the knowledge accumulated on animal models of diabetes during the last decade. The most commonly used diabetes models and the underlying disease processes are summarized, respectively. The best known diabetogenic substances, Streptozotocin and Alloxan are described, including their usage, dosage dosing intervals, and mechanism of action. The latest results are included in the article which discuss the possible role of free radical-induced injury of beta cells in Streptozotocin and Alloxan diabetes.