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1.
J Natl Cancer Inst ; 84(1): 47-51, 1992 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-1738173

RESUMEN

Studies suggest that cell proliferation abnormalities of the colorectal mucosa are associated with risk of neoplasia, and most cancers of the large bowel are thought to arise from adenomas. The results of other studies suggest that vitamins A, C, and E have chemopreventive efficacy against colon cancer in animal models. This study evaluates the effect of dietary vitamin supplementation on cell kinetics in uninvolved rectal mucosa in patients with colorectal adenomas. Twenty patients with colorectal adenomas were given vitamins A, C, and E for 6 months after complete polypectomy, and 21 patients with adenomas received placebo. In each patient, six biopsy specimens were taken from normal-appearing rectal mucosa before treatment and after 3 and 6 months of treatment and were incubated with tritiated thymidine ([3H]thymidine), and the [3H]thymidine-labeled cells were counted by use of autoradiography. Two parameters of cell proliferation were evaluated: 1) the ratio of the number of labeled cells to the total number of cells (thymidine labeling index) and 2) the ratio of the number of labeled cells in the upper 40% of the crypt to the total number of labeled cells in the crypt (phi h). The latter index reflects abnormal expansion of the proliferative compartment and is thought to be an intermediate biomarker of cancer risk. In patients receiving vitamins, phi h decreased progressively from baseline values, with increasing statistical significance (P less than .05 after 3 months, P less than .01 after 6 months). There was a statistically significant decrease in the thymidine labeling index in the 40% of the crypt near the mucosal surface, but the variation in the overall labeling index was not statistically significant. In the placebo group, we observed no statistically significant change in cell kinetics. These findings suggest that vitamin A, C, and E supplementation is effective in reducing abnormalities in cell kinetics that may indicate a precancerous condition. Before larger trials on chemoprevention of colorectal adenoma recurrence are conducted, additional studies are needed (a) to validate that cell kinetics is an intermediate biomarker, (b) to determine active agents, optimal dosage, and the relative efficacy of agents given alone and in combination, and (c) to test toxicity.


Asunto(s)
Adenoma/prevención & control , Anticarcinógenos/farmacología , Neoplasias Colorrectales/prevención & control , Mucosa Intestinal/efectos de los fármacos , Vitaminas/farmacología , Adulto , Anciano , Anciano de 80 o más Años , Ácido Ascórbico/farmacología , División Celular/efectos de los fármacos , Femenino , Humanos , Mucosa Intestinal/patología , Masculino , Persona de Mediana Edad , Recto/efectos de los fármacos , Recto/patología , Vitamina A/farmacología , Vitamina E/farmacología
2.
Cancer Res ; 44(11): 5450-4, 1984 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6488197

RESUMEN

Two markers related to preneoplasia were studied simultaneously in ulcerative colitis (UC). The renewal of the rectal epithelial cells together with expression of second-trimester fetal antigen (STFA) were evaluated in nine patients with UC and four healthy subjects. Endoscopic biopsies were incubated with tritiated thymidine. Cell renewal was studied with microautoradiography, and the antigenic properties of the cells were evaluated by indirect immunofluorescence. At the time of the study, all the UC patients were in a mildly active or in a quiescent stage of the disease; their biopsies did not show dysplastic or neoplastic changes in epithelial cells. STFA was expressed in five UC patients. The analysis of cell renewal in this group revealed a shift of the proliferative compartment towards the luminal surface of the colonic crypts. By contrast, the patient group with STFA-negative reactions showed a pattern of cell proliferation similar to that observed in the controls. These results suggest that the expression of STFA in colonic mucosa is associated with an expansion of the epithelial stem cell population or with arrested cell differentiation, and it may represent a phenotypic marker of proneness of the mucosa toward neoplastic development.


Asunto(s)
Antígenos/análisis , Colitis Ulcerosa/patología , Mucosa Intestinal/patología , Recto/patología , Adolescente , Adulto , Anciano , Antígenos de Superficie/análisis , Biopsia , División Celular , Colitis Ulcerosa/inmunología , Replicación del ADN , Femenino , Humanos , Mucosa Intestinal/inmunología , Masculino , Persona de Mediana Edad , Embarazo , Recto/inmunología
3.
Cancer Res ; 50(4): 1156-9, 1990 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-2297764

RESUMEN

Cell proliferation kinetics of 30 patients affected by extensive ulcerative colitis in remission have been studied with autoradiography of rectal biopsies incubated with tritiated thymidine. The results have been compared with those of 20 control subjects without evidence of colonic diseases, and of 16 patients with multiple nonfamilial colonic adenomas. The labeling index was similar in the three groups (P = NS). On the contrary, the labeling frequency (SEM) in the upper 40% of the crypt (phi h value) was 0.04 +/- 0.01 in controls, 0.16 +/- 0.02 in ulcerative colitis, and 0.10 +/- 0.01 in adenoma patients (P less than 0.001 ulcerative colitis versus controls, P less than 0.01 adenomas versus controls, P = NS ulcerative colitis versus adenomas). The distribution of phi h values in ulcerative colitis showed a bimodal trend with 22 patients having mean phi h values similar to adenoma patients (0.10 +/- 0.01) and 8 with higher values (0.30 +/- 0.02). No relationship was found between phi h values and duration of colitis, age of patients, or age at onset of symptoms. These data show that cell kinetics studies can detect patients at particularly high risk of colon cancer, and that additional factors should determine colon cancer risk level in ulcerative colitis.


Asunto(s)
Adenoma/patología , Colitis Ulcerosa/patología , Neoplasias del Colon/patología , Recto/patología , Adulto , Anciano , Biopsia , División Celular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Lesiones Precancerosas/patología
4.
Minerva Gastroenterol Dietol ; 51(3): 247-54, 2005 Sep.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-16280966

RESUMEN

AIM: The diagnosis of Helicobacter pylori infection can be made easily by the rapid urease test during endoscopy. The mainly commercial rapid urease test available in routine practice, is in liquid phase, need to be stored at 4 degrees C and generally they are not ready to use. Recently a new rapid urease test, the Pronto Dry, has been reported to be faster in the final reading, ready to use, and it can be stored at room temperature. Aim of the study was to evaluate the diagnostic accuracy and the reaction time of Pronto Dry vs liquid phase-rapid urease test, before and after treatment of Helicobacter pylori infections. METHODS: A total of 315 untreated dyspeptic patients and 323 post-treatment patients, were enrolled in this study. At endoscopy, 5 biopsy samples were obtained from the antrum and from the corpus for histology; culture and rapid urease tests (liquid phase and Dry test). Helicobacter pylori status was defined according to European guidelines. Sensitivity and specificity of both rapid urease test were assessed at 5, 15, 30 minutes, and 3 and 24 hours after the endoscopy. RESULTS: One hundred and eleven out of 315 untreated dyspeptic patients were found to be positive for Helicobacter pylori infection, and 56/323 patients were found still positive after treatment. Sensitivity at 5, 15, 30 minutes, and 3 and 24 hours in untreated patients were 45%, 71.2%, 81.1%, 90.1% and 91.9% respectively for the Pronto Dry vs 6.3%, 31.5%, 51.3%, 78.4% and 90.1% for liquid phase rapid urease test. Sensitivity at the same times in not eradicated patients were 33.9%, 66.1%, 85.7%, 92.8 and 92.8% respectively for the Pronto Dry vs 3.6%, 37.5%, 55.3%73.2%, 92.8% for liquid phase rapid urease test. CONCLUSIONS: Pronto Dry showed to have higher sensitivity in pre and post treatment setting compared to liquid phase-rapid urease test within 3 hours of incubation time.


Asunto(s)
Pruebas Enzimáticas Clínicas , Infecciones por Helicobacter/diagnóstico , Helicobacter pylori , Ureasa/análisis , Humanos , Reproducibilidad de los Resultados , Factores de Tiempo
5.
J Clin Endocrinol Metab ; 55(2): 329-36, 1982 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7045154

RESUMEN

Hypersecretion of immunoreactive gastric inhibitory polypeptide (IRGIP) has been reported previously in patients with diabetes mellitus (DM) and obesity. To ascertain the relative contribution of glucose intolerance and obesity to the abnormalities of IRGIP secretion, 114 subjects were studied during a standard oral glucose (75 g) tolerance test; responses of glucose, insulin, C-peptide, IRGIP, and glucagon were evaluated. The subjects were divided into six subgroups according to body weight and the degree of glucose intolerance. In normal weight subjects, the IRGIP response to oral glucose was significantly higher in the patients with impaired glucose tolerance (IGT) and DM than in the healthy control subjects (P less than 0.05). In the obese subjects, no significant differences in mean IRGIP responses could be detected among control, IGT, and DM subjects. In spite of similar IRGIP responses, the obese IGT patients did release more insulin than the obese control subjects, suggesting that incretin factors other than GIP may be operative in this condition. When obese and nonobese patients were compared, the obese subjects with normal glucose tolerance released a greater amount of IRGIP and insulin than the normal weight controls, whereas no significant difference between obese and nonobese could be found within the IGT and DM groups. We conclude that in the absence of obesity, glucose intolerance may induce IRGIP hypersecretion. On the other hand, obesity is associated with IRGIP hypersecretion, and glucose intolerance has no further effect, indicating a different pathogenetic mechanism for the IRGIP abnormalities. In both the obese and nonobese diabetic groups, IRGIP hypersecretion was associated with a failure of plasma glucagon levels to fall after oral glucose; this effect might be related to the glucagonotropic action of this peptide.


Asunto(s)
Diabetes Mellitus/fisiopatología , Polipéptido Inhibidor Gástrico/sangre , Hormonas Gastrointestinales/sangre , Obesidad/fisiopatología , Adulto , Glucemia/análisis , Peso Corporal , Péptido C/sangre , Femenino , Glucagón/sangre , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/sangre , Masculino , Persona de Mediana Edad
6.
Am J Clin Nutr ; 68(4): 888-93, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9771867

RESUMEN

BACKGROUND: Infusion of lipid emulsions rich in polyunsaturated fatty acids (PUFAs) may increase lipid peroxidation, which is counteracted mainly by superoxide dismutase (SOD) (a zinc-, copper-, and manganese-dependent enzyme), selenium-dependent glutathione peroxidase (Se-GSHPx), and alpha-tocopherol. OBJECTIVE: We investigated lipid peroxidation and antioxidant status in patients receiving home parenteral nutrition (HPN) providing variable amounts of a lipid emulsion rich in PUFAs, and alpha-tocopherol, zinc, copper, and manganese as recommended by the American Medical Association, and no selenium. DESIGN: Serum malondialdehyde, plasma alpha-tocopherol, selenium, Se-GSHPx, PUFAs, and red blood cell Se-GSHPx and SOD were evaluated in 12 patients and in 25 healthy control subjects. Malondialdehyde was also assessed in a group of 40 healthy control subjects. RESULTS: Patients had significantly higher concentrations of malondialdehyde and SOD and lower alpha-tocopherol concentrations and selenium nutritional status. Linear regression analysis showed that malondialdehyde was associated with the daily PUFA load (r=0.69, P< 0.03) and with plasma alpha-tocopherol (r=-0.59, P< 0.05), but stepwise multiple regression analysis confirmed only the association between malondialdehyde and alpha-tocopherol; plasma alpha-tocopherol was associated with the daily PUFA load (r=-0.65, P< 0.04) and with the duration of HPN (r=-0.74, P< 0.02). CONCLUSIONS: In HPN patients, the peroxidative stress due to lipid emulsions rich in PUFAs is counteracted primarily by alpha-tocopherol. The dosages of alpha-tocopherol, zinc, copper, and manganese recommended by the American Medical Association appear sufficient to sustain SOD activity but inadequate to maintain alpha-tocopherol nutritional status. HPN formulations should be supplemented with selenium.


Asunto(s)
Antioxidantes/metabolismo , Emulsiones Grasas Intravenosas/administración & dosificación , Peroxidación de Lípido , Nutrición Parenteral en el Domicilio , Adolescente , Adulto , Ácidos Grasos Insaturados/administración & dosificación , Femenino , Glutatión Peroxidasa/sangre , Humanos , Masculino , Malondialdehído/sangre , Persona de Mediana Edad , Análisis de Regresión , Selenio/sangre , Superóxido Dismutasa/sangre , Vitamina E/sangre
7.
Cancer Epidemiol Biomarkers Prev ; 6(6): 469-71, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9184782

RESUMEN

It has been suggested that colon cancer risk in ulcerative colitis (UC) is correlated to a reduced bioavailability of folate. We studied the effects of folate supplementation on the pattern of rectal cell proliferation in patients affected by long-standing UC. In the rectal mucosa of these patients, an expansion of proliferating cells to the crypt surface is found frequently. This abnormality is considered an intermediate biomarker in chemoprevention trials. Twenty-four patients (13 males; age, 26-70 years; UC duration, 7-34 years) with UC in remission for 1 month at least were assigned randomly to one of the following treatments: (a) folinic acid (15 mg/day) or (b) placebo. Cell proliferation was analyzed through immunohistochemistry on sections of rectal biopsies incubated for 1 hour in a culture medium containing bromodeoxyuridine. Fragments were taken at admission to the study and after 3 months of treatment. As compared to the baseline values, after 3 months of therapy in patients treated with folinic acid, a significant reduction of the frequency of occurrence of labeled cells in the upper 40% of the crypts (phi h value) was observed (0.1836 +/- 0.0278 versus 0.1023 +/- 0.0255; P < 0.01). On the contrary, no significant proliferative changes were observed in the placebo group. These results suggest that folate supplementation contributes to regulating rectal cell proliferation in patients with long-standing UC. These findings may be significant for chemoprevention of colon cancer in these patients.


Asunto(s)
Colitis Ulcerosa/tratamiento farmacológico , Colitis Ulcerosa/patología , Leucovorina/uso terapéutico , Recto/patología , Adulto , Anciano , Biopsia , División Celular , Colitis Ulcerosa/complicaciones , Neoplasias Colorrectales/etiología , Método Doble Ciego , Femenino , Humanos , Inmunohistoquímica , Leucovorina/sangre , Masculino , Persona de Mediana Edad , Índice Mitótico , Membrana Mucosa/patología , Estudios Prospectivos
8.
Cancer Lett ; 53(2-3): 117-21, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2208070

RESUMEN

We evaluated the influence of age and sex on rectal cell proliferation of 69 hospital controls and 66 patients with colorectal adenomas, by means of incubation of rectal biopsies with tritiated thymidine and autoradiography. In particular, we evaluated the labeling frequency in the upper 40% of rectal crypts (0 h), actually considered as a reliable kinetic marker of colon cancer risk. A direct correlation between 0h and age was found in control subjects (P less than 0.02) but not in adenomas patients (P = NS). Moreover, control subjects over 65 years of age showed a shift of the proliferative compartment similar to that observed in the adenomas group. After adjusting for the age, we did not observe any significant effect of the sex of patients or controls on their cell kinetics parameters. Our results are in agreement with those previously reported on smaller series and with epidemiological studies which indicate a high risk for developing colorectal neoplasia in the elderly subjects.


Asunto(s)
Adenoma/patología , Neoplasias Colorrectales/patología , Recto/citología , Recto/patología , Adulto , Factores de Edad , Anciano , División Celular , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Factores Sexuales
9.
Cancer Lett ; 73(1): 23-8, 1993 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-8402594

RESUMEN

We evaluated the presence of cell proliferation and antigenic abnormalities in rectal biopsies from 37 patients affected by ulcerative colitis and 15 controls. The study was carried out by thymidine labeling and immunochemistry, using antibodies against specific cytoskeletal-associated proteins (p52, p35, alpha-actinin). Among ulcerative colitis patients, 24 had an immunofluorescence pattern similar to that of controls, while 13 showed an abnormal distribution of one or more proteins (p52 alone or p52 and either p35 or alpha-actinin) within the rectal crypts. Patients showed a shift of the proliferative compartment towards the top of the rectal crypts compared with controls. This finding was more evident in patients with p52 or p35 abnormalities. Proliferative and antigenic defects were not related either to age or the duration of colitis. These phenotypic changes might be a biomarker of increased risk of colon cancer in ulcerative colitis.


Asunto(s)
Colitis Ulcerosa/metabolismo , Colitis Ulcerosa/patología , Neoplasias Colorrectales/etiología , Proteínas del Citoesqueleto/análisis , Adulto , Anciano , Autorradiografía , Biomarcadores/análisis , División Celular , Colitis Ulcerosa/fisiopatología , Neoplasias Colorrectales/diagnóstico , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad
10.
Aliment Pharmacol Ther ; 16 Suppl 1: 16-23, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11849123

RESUMEN

Helicobacter pylori (H. pylori) infection can be diagnosed by invasive techniques requiring endoscopy and biopsy (histological examination, culture, polymerase chain reaction) and by noninvasive techniques (serology, urea breath test, urine or blood, detection of H. pylori antigen in stool specimen). At present, no single test can be absolutely relied upon to detect colonization by H. pylori, and a combination of two tests is recommended if feasible. The tests used should depend on the clinical circumstances, the likelihood ratio of positive and negative tests, the cost-effectiveness of the testing strategy, and the availability of the tests. Some clinical circumstances warrant invasive studies, principally patients with alarm symptoms (bleeding, weight loss, etc.) as well as older patients with new-onset dyspepsia. Endoscopy may also be advisable in patients who have failed eradication therapy and need culture and antimicrobial sensitivity testing to determine an appropriate regimen. Recent studies have also demonstrated that a strategy to 'test and treat' for H. pylori in uninvestigated, young (< 50 years), dyspeptic patients in primary care is safe and reduces the need for endoscopy. Indeed, a number of clinical guidelines recommend noninvasive testing followed by treatment of H. pylori for dyspeptic patients in primary care based on clinical and economic analyses.


Asunto(s)
Infecciones por Helicobacter/diagnóstico , Helicobacter pylori/aislamiento & purificación , Biopsia , Costos y Análisis de Costo , Infecciones por Helicobacter/sangre , Infecciones por Helicobacter/microbiología , Helicobacter pylori/crecimiento & desarrollo , Humanos , Reacción en Cadena de la Polimerasa , Pruebas Serológicas , Estómago/enzimología , Ureasa/metabolismo
11.
Aliment Pharmacol Ther ; 16(6): 1075-82, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12030948

RESUMEN

AIM: : To decrease the intensity of dyspeptic symptoms by impairing the visceral nociceptive C-type fibres with capsaicin, contained in red pepper powder. METHODS: : The study was performed on 30 patients with functional dyspepsia and without gastro-oesophageal reflux disease and irritable bowel syndrome. After a 2-week washout period, 15 patients received, before meals randomly and in a double-blind manner, 2.5 g/day of red pepper powder for 5 weeks, and 15 patients received placebo. A diary sheet was given to each patient to record, each day, the scores of individual and overall symptom intensity, which subsequently were averaged weekly and over the entire treatment duration. RESULTS: : The overall symptom score and the epigastric pain, fullness and nausea scores of the red pepper group were significantly lower than those of the placebo group, starting from the third week of treatment. The decrease reached about 60% at the end of treatment in the red pepper group, whilst placebo scores decreased by less than 30%. CONCLUSIONS: : Red pepper was more effective than placebo in decreasing the intensity of dyspeptic symptoms, probably through a desensitization of gastric nociceptive C-fibres induced by its content of capsaicin. It could represent a potential therapy for functional dyspepsia.


Asunto(s)
Capsaicina/farmacología , Capsicum , Dispepsia/tratamiento farmacológico , Adulto , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Náusea/tratamiento farmacológico , Náusea/etiología , Dolor/tratamiento farmacológico , Dolor/etiología , Placebos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
12.
Aliment Pharmacol Ther ; 15(2): 157-61, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11148432

RESUMEN

BACKGROUND: Sildenafil shows an intense and prolonged inhibitory effect on the smooth muscle cells of corpus cavernosum arterioles by blocking phosphodiesterase-type 5, which inactivates the nitric oxide-stimulated cyclic guanosine monophosphate. AIM: To investigate whether this inhibitory effect is also displayed on the musculature of the gastroduodenal tract. METHODS: In 16 normal subjects, antroduodenal motility was recorded by means of a low-compliance manometric system. Ten minutes after the appearance of a phase III of the migrating motor complex, a tablet of sildenafil 50 mg, dissolved in 20 mL of water, was infused in the gut of eight patients, or a placebo in the other eight patients, randomly and in a double-blind manner, continuing the recording for 90 min. The frequency and amplitude of antral and duodenal waves, measured during the first 60 min after infusion in the two groups, were compared statistically. In addition, the duration of antral and duodenal phases I, and the number of phases III occurring during the whole 90 min after infusion, were compared in the two groups. RESULTS: Antral and duodenal wave frequency and amplitude were significantly lower during the first 60 min after sildenafil administration. Both antral and duodenal phases I were significantly longer after sildenafil than after placebo, and the number of phases III which occurred during the 90 min after sildenafil was significantly lower than after placebo. CONCLUSIONS: Sildenafil inhibits interdigestive motor activity of the antrum and duodenum.


Asunto(s)
Motilidad Gastrointestinal/efectos de los fármacos , Piperazinas/farmacología , Adulto , Método Doble Ciego , Duodeno/efectos de los fármacos , Duodeno/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Inhibidores de Fosfodiesterasa/efectos adversos , Inhibidores de Fosfodiesterasa/farmacología , Piperazinas/efectos adversos , Purinas , Antro Pilórico/efectos de los fármacos , Antro Pilórico/fisiología , Citrato de Sildenafil , Sulfonas
13.
Aliment Pharmacol Ther ; 12(10): 1021-5, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9798808

RESUMEN

BACKGROUND: Clarithromycin and amoxycillin are antibiotics commonly used in association for Helicobacter pylori eradication. Because this treatment, which lasts 1-2 weeks, is frequently associated with gastrointestinal symptoms, we investigated the effects of these antibiotics on gastrointestinal motility. PATIENTS AND METHODS: Gastroduodenal motility was recorded in 14 patients with functional dyspepsia and H. pylori gastritis by means of a low-compliance manometric system with four recording ports in the stomach and four in the duodenum. Two tablets of clarithromycin 250 mg (seven patients, clarithromycin group) or one of amoxycillin 1 g (seven patients, amoxycillin group), ground and dissolved in 20 mL of water, were given randomly and in double-blind manner 30 min after the end of the first activity front (AF) of the migrating motor complex (MMC) or, in the absence of AFs, after at least 200 min of recording. Recording continued until an AF was observed during the subsequent 200 min. RESULTS: Clarithromycin administration was followed by a typical gastroduodenal AF in a significantly higher number of patients than for amoxycillin administration. In addition, the time lag between clarithromycin administration and the appearance of AFs was 48 min +/- 8.5 (mean +/- s.d.), significantly shorter than after amoxycillin (121 min +/- 29). The clarithromycin-related duodenal AFs showed a duration of 6.6 min +/- 1.5, significantly longer than that of the spontaneous AFs (3.6 min +/- 1.2, P < 0.01), while the amoxycillin-related AFs were not significantly different from the spontaneous ones. CONCLUSION: Clarithromycin stimulated cyclic gastroduodenal motility, while amoxycillin was ineffective. It is likely that symptoms during the eradication treatment are due to this effect of clarithromycin.


Asunto(s)
Amoxicilina/farmacología , Claritromicina/farmacología , Quimioterapia Combinada/farmacología , Dispepsia/inducido químicamente , Motilidad Gastrointestinal/efectos de los fármacos , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori , Administración Oral , Adulto , Amoxicilina/efectos adversos , Claritromicina/efectos adversos , Método Doble Ciego , Quimioterapia Combinada/efectos adversos , Femenino , Infecciones por Helicobacter/fisiopatología , Humanos , Masculino , Persona de Mediana Edad
14.
Aliment Pharmacol Ther ; 8(5): 535-40, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7865646

RESUMEN

AIMS: An oral multiparticulate coated formulation of 5-aminosalicylic acid (5-ASA: mesalazine) has been developed to provide a controlled release of the drug, in a pH-dependent fashion, in the distal ileum and colon. The purpose of the present study was to assess the systemic availability of the drug and its metabolite, acetyl-5-ASA, following single (800 mg) and multiple (2400 mg for 56 days) oral dose administration. METHODS: Three groups were investigated: six healthy volunteers, six patients with ulcerative colitis, and nine patients with Crohn's disease in remission. In the single oral dose study (800 mg) all three groups participated, whereas in the multiple oral dose study (2400 mg/day for 56 days) only the patients with inflammatory bowel disease took part. Plasma and urine 5-ASA and Ac-5-ASA were measured for 48 h. RESULTS: In the single oral dose regimen, systemic absorption of 5-ASA and Ac-5-ASA were low and did not differ between the three groups. Only about 20% of the 5-ASA given was absorbed, with more than 80% of the drug being available in the terminal ileum and colon for therapeutic activity. The multiple oral dose regimen in patients with inflammatory bowel disease produced a significantly higher plasma concentration and urine excretion of both 5-ASA and Ac-5-ASA by the end of the treatment, in comparison to the first dose. There was a statistically higher systemic absorption of 5-ASA in patients with ulcerative colitis than in patients with Crohn's disease. After 56 days of dosing, no adverse event was reported and laboratory screening tests remained within normal ranges. CONCLUSIONS: The new oral 5-ASA formulation is gradually released throughout the small and large intestine, reflected by a low plasma concentration of the drug and its metabolite, with about 80% of the drug being available for ileum-colon therapeutic activity.


Asunto(s)
Ácidos Aminosalicílicos/farmacocinética , Antiinflamatorios no Esteroideos/farmacocinética , Colitis Ulcerosa/metabolismo , Enfermedad de Crohn/metabolismo , Administración Oral , Adulto , Anciano , Ácidos Aminosalicílicos/administración & dosificación , Ácidos Aminosalicílicos/efectos adversos , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/efectos adversos , Disponibilidad Biológica , Colitis Ulcerosa/sangre , Enfermedad de Crohn/sangre , Esquema de Medicación , Femenino , Humanos , Masculino , Mesalamina , Persona de Mediana Edad
15.
Aliment Pharmacol Ther ; 10(4): 601-5, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8853765

RESUMEN

AIM: To determine the systemic uptake of 5-aminosalicylic acid (5-ASA) and acetyl-5-ASA (Ac-5-ASA) at steady state during treatment with either an azo-bond preparation, olsalazine, or a delayed-release mesalazine. METHODS: In an open cross-over trial with randomized sequence, 15 patients with ulcerative colitis in remission were given 7-day courses of olsalazine (Dipentum 1.0 g daily) and of mesalazine (Asacol 1.6 g daily). Plasma and urine were collected on days 6 and 7 of each course and concentrations of 5-ASA and Ac-5-ASA were determined by high-performance liquid chromatography (HPLC). RESULTS: Mean steady-state plasma concentrations of 5-ASA and Ac-5-ASA were significantly higher after treatment with mesalazine than with olsalazine (P < 0.0001). Total urinary excretion of 5-ASA and Ac-5-ASA as a percentage of the given dose was significantly higher on mesalazine than on olsalazine (P < 0.01). Only two patients experienced, during the first 3 days of treatment with olsalazine, transient watery diarrhoea which resolved spontaneously. No unexpected or major changes in haematology or biochemistry were detected during the study. CONCLUSION: As 5-ASA acts locally, the lower systemic load provided by olsalazine may increase efficacy and reduce the potential risk of nephrotoxicity during long-term maintenance treatment of ulcerative colitis.


Asunto(s)
Ácidos Aminosalicílicos/farmacocinética , Antiinflamatorios no Esteroideos/farmacocinética , Profármacos/farmacocinética , Adulto , Anciano , Ácidos Aminosalicílicos/administración & dosificación , Ácidos Aminosalicílicos/orina , Antiinflamatorios no Esteroideos/administración & dosificación , Disponibilidad Biológica , Colitis Ulcerosa/tratamiento farmacológico , Estudios Cruzados , Preparaciones de Acción Retardada , Femenino , Humanos , Masculino , Mesalamina , Persona de Mediana Edad , Profármacos/administración & dosificación
16.
Aliment Pharmacol Ther ; 15 Suppl 1: 33-42, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11488660

RESUMEN

The mode of transmission of Helicobacter pylori is largely unknown and is a matter of circumstantial evidence and speculation rather than fact. However, the principle evidence is of two sorts: the epidemiological data, providing evidence of possible risk factors associated with transmission, and the identification of potential sources from which H. pylori could be acquired. Evidence exists for several potential sources of infection and several possible modes of transmission, and it is feasible that the transmission of H. pylori varies according to the cultural and demographic circumstances. However, the most likely recognized source for H. pylori is the human stomach, although it is not known by what route the organism is transmitted to the stomach. Evidence suggests close personal contact is important and that acquisition occurs mainly in childhood. This article reviews the evidence for the source of infection and the route of transmission of H. pylori.


Asunto(s)
Infecciones por Helicobacter/transmisión , Helicobacter pylori/aislamiento & purificación , Factores de Edad , Países en Desarrollo , Reservorios de Enfermedades , Heces/microbiología , Heterogeneidad Genética , Infecciones por Helicobacter/etnología , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , Humanos , Boca/microbiología , Exposición Profesional , Factores Socioeconómicos , Estómago/microbiología , Estómago/fisiopatología
17.
Aliment Pharmacol Ther ; 17 Suppl 2: 89-97, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12786619

RESUMEN

The year 2002 saw advances on many fronts in the study of Helicobacter and gastroduodenal disease. Several studies have confirmed endoscopy as a valuable management procedure with confirmation of the diagnostic utility of the rapid urease test and the description of a new formulation of the test, which is more rapid in giving a result. Serology has been re-confirmed as a useful investigation in selected populations. Some commercial kits for near patient testing have also been assessed and although generally regarded as less accurate than laboratory based tests some have shown acceptable accuracy. The recent exciting development in diagnostic serology is the availability of the faecal antigen test; further studies have confirmed its usefulness as recommended screening tests. There have been several studies demonstrating that a test and treat policy has a significant patient benefit, both economic and medical, although there is some doubt if eradication of Helicobacter leads to regression of atrophy and metaplasia. However, in low Helicobacter-prevalence areas the test and treat policy is being challenged as an effective management strategy. Further studies have shown that compliance with treatment regimens is an important determinant of successful eradication. Finally several new eradication regimens have been reported particularly for use in patients who have had previous unsuccessful eradication attempts.


Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Biopsia/métodos , Endoscopía Gastrointestinal , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/terapia , Humanos , Cooperación del Paciente , Sistemas de Atención de Punto , Pruebas Serológicas/métodos
18.
Aliment Pharmacol Ther ; 16 Suppl 4: 105-13, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12047269

RESUMEN

The main areas of this review are Helicobacter pylori and disease pathogenesis; the relationship of H. pylori to lower gastrointestinal diseases, liver disease and extra-gastrointestinal conditions; the relationship of H. pylori to gastro-oesophageal reflux disease; infection in the very young and very old; diagnostic techniques; and management of H. pylori infections with particular emphasis on eradication regimens and antibiotic resistance.


Asunto(s)
Enfermedades Gastrointestinales/microbiología , Infecciones por Helicobacter/complicaciones , Helicobacter pylori/patogenicidad , Adulto , Factores de Edad , Anciano , Niño , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/tratamiento farmacológico , Humanos , Lactante , Hepatopatías/microbiología , Neoplasias Gástricas/microbiología
19.
Aliment Pharmacol Ther ; 14(12): 1613-7, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11121909

RESUMEN

BACKGROUND: Azithromycin is an acid-stable macrolide that achieves remarkably high concentrations in gastric tissue, persisting above the MIC90 for Helicobacter pylori over a period of 5-days, after a single 500 mg oral dose. AIM: To evaluate and compare the efficacy, safety, and tolerability of two eradicating regimens of pantoprazole, azithromycin and tinidazole. METHODS: A total of 100 consecutive symptomatic H. pylori-positive patients received pantoprazole 40 mg b.d. for 1 week, and were randomly assigned to either azithromycin 500 mg o.m. and tinidazole 500 mg b.d. during the first 3 days (early group, n=50) or during the last 3 days of therapy with pantoprazole (late group, n=50). H. pylori status was assessed by histology and rapid urease test at entry and by histology and 13C-urea breath test 1 month after the end of the therapy. RESULTS: Ninety-nine patients completed the study. H. pylori was eradicated in 86% of patients in the early group (intention-to-treat 86%) and in 88% of patients in the late group (intention-to-treat 88%). CONCLUSIONS: This short triple therapy is effective for H. pylori eradication. The compliance was excellent and side-effects negligible. Moreover, the pantoprazole pre-treatment did not modify the efficacy of the therapy.


Asunto(s)
Azitromicina/administración & dosificación , Bencimidazoles/administración & dosificación , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori , Sulfóxidos/administración & dosificación , Tinidazol/administración & dosificación , 2-Piridinilmetilsulfinilbencimidazoles , Adulto , Anciano , Quimioterapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Omeprazol/análogos & derivados , Pantoprazol , Estudios Prospectivos , Factores de Tiempo
20.
Aliment Pharmacol Ther ; 14 Suppl 3: 13-22, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11050483

RESUMEN

There are two general ways in which a diagnosis of infection by Helicobacter pylori can be made: by using either an invasive or non-invasive procedure. The invasive procedures involve an endoscopy and biopsy. A biopsy is essential because often the mucosa may appear macroscopically normal but nevertheless be inflamed. A biopsy is obtained by histological examination, culture, polymerase chain reaction or detection of the presence of urease activity in biopsy material. The non-invasive tests that can be used to diagnose the infection are serology, detection of labelled metabolic products of urea hydrolysis in the breath (13CO2, 14CO2), the urine or the blood, and detection of H, pylori antigen in a stool specimen. At present no single test can be relied upon to detect definitely colonization by H. pylori, and a combination of two is recommended if this is feasible. The choice of the test to be used is not straightforward and may vary according to the clinical condition and local expertise.


Asunto(s)
Infecciones por Helicobacter/diagnóstico , Helicobacter pylori , Pruebas Respiratorias , Infecciones por Helicobacter/microbiología , Helicobacter pylori/efectos de los fármacos , Humanos
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