Search

Stromal tumors represent 1-3% of all primary gastric neoplasms. These tumors can occur at any age and display different clinical manifestations, but they rarely reach over 10 cm in size. Currently they are designed as gastrointestinal stromal tumors (GIST) but their classification is still controversial. Surgery is the treatment of choice, and the extension of surgical resection depends on the tumor size, neoplastic involvement of adjacent organs, and the presence of metastatic disease. In selected cases minimally invasive surgery can provide excellent results. We present four new patients with GIST who exemplify the different clinical forms of presentations of GISTs and their diverse treatment options. Los tumores estromales representan el 1-3% de las neoplasias gástricas primitivas. Se pueden presentar a cualquier edad, bajo muy diversas formas clínicas, siendo raro que alcancen un tamaño superior a los 10 cm. Estos raros tumores se encuadran en la actualidad dentro de los denominados tumores del estroma gastrointestinal (GIST´s) , cuya clasificación continúa siendo controvertida. La cirugía es el tratamiento de elección y su extensión viene determinada por el tamaño del tumor, la afectación de órganos vecinos y la presencia o no de metástasis. En casos seleccionados, la cirugía mínimamente invasiva puede llevarse a cabo con excelentes resultados. Presentamos cuatro casos que resumen las distintas formas de presentación clínica de estos tumores así como su manejo terapéutico.

The hairless (hr) gene is expressed in a large number of tissues, primarily the skin, and a mutation in the hr gene is responsible for the typical cutaneous phenotype of hairless mice. Mutant hr mouse strains show immune defects involving especially T cells and macrophages, as well as an age-related immunodeficiency and an accelerated atrophy of the thymus. These data suggest that the hr mutation causes a defect of this organ, although hr transcripts have not been detected in fetal or adult mice thymus. The present study analyses the thymus of young (3 mo) and adult (9 mo) homozygous hr-rh-j mice (a strain of hairless mice) by means of structural techniques and immunohistochemistry to selectively identify thymic epithelial cells, dendritic cells, and macrophages. There were structural alterations in the thymus of both young and adult rh-rh-j mice, which were more severe in older animals. These alterations consisted of relative cortical atrophy, enlargement of blood vessels, proliferation of perivascular connective tissue, and the appearance of cysts. hr-rh-j mice also showed a decrease in the number of epithelial and dendritic cells, and macrophages. Taken together, present results strongly suggest degeneration and accelerated age-dependent regression of the thymus in hr-rh-j mice, which could explain at least in part the immune defects reported in hairless mouse strains., This work was supported in part by a grant from Spanish DGES PB-95}1064 to JAV.

Cystic fibrosis is a common lethal heritable disorder, caused by a defect in a chloride channel protein, namely CFTR. After the identification of the gene and its product by positional cloning (on chromosome 7), CFTR has been characterized as a low conductance (8-10 pSiemens) linear chloride channel, which appears to regulate other apical transport proteins. Two therapeutic options are reviewed: gene transfection and drug therapy. So far, clinical studies have shown that gene transfection cannot effectively restore CFTR function. Simultaneously, several drugs including genistein, phenylimidazothiazoles and gentamicin have been found to activate mutant CFTR, thus, being suitable for single or combined (with gene transfection) treatment.

A comparative, case-control study on the pre- and postprandial release of three gastrointestinal peptides implicated in gallbladder motility has been carried out in humans in the attempt to determine their possible role in the pathogenesis of cholelithiasis. Fifty-seven adult patients (40 females and 17 males) with an ultrasound diagnosis of gallstones and 20 healthy subjects (9 females and 11 males) without cholelithiasis or other digestive pathology were studied. Plasma substance P, neurotensin and somatostatin were measured by means of RIA-I125 in basal fasting conditions and 30, 60 and 90 minutes after the oral intake of a semiliquid mixed meal. The levels of secretion of each hormone were compared in patients and healthy controls on an overall basis and in terms of sex, age and body weight. We found a basal and postprandial hypersecretion of substance P in patients with gallstones when compared with controls. Individuals with cholelithiasis showed a moderate decrease in neurotensin secretion after the oral meal. Somatostatin release was unchanged. In conclusion, patients with gallstones may present a functional disorder in the secretion of gastrointestinal hormones involved in gallbladder motility.

We report the case of a 57 years old male patient presenting with pyrosis and dysphagia. A mid-third esophageal leiomyoma was diagnosed. The tumour was resected through a right video-thoracoscopic approach and simultaneous intraoperative esophagoscopy was performed. The postoperative course was uneventful and six months after surgery neither relapsing symptoms nor radiologic pathological findings were observed. We consider that symptomatic leiomyoma is a good indication for video-assisted thoracoscopic enucleation. The possible postoperative complications (esophageal fistula, esophageal pseudodiverticulum) may be minimized by means of an adequate surgical technique.

2 páginas, 1 figura, 1 tabla.-- et al.

Laparoscopic cholecystectomy has become the treatment of choice for symptomatic cholelithiasis. However, the indication of the laparoscopic approach for acute inflammation of the gallbladder in unclear and further analysis of the results is required. The aim of our study was to compare the results of laparoscopic cholecystectomy after uncomplicated cholelithiasis and after acute cholecystitis. Data from 201 patients who underwent laparoscopic cholecystectomy were collected prospectively. Uncomplicated cholelithiasis was present in 149 patients and 52 individuals had acute cholecystitis. No differences in age, sex distribution or associated diseases were observed between groups. The mean operative time was significantly higher in patients with acute cholecystitis. However, no difference was observed regarding conversion rate (7.3%-7.6%) and morbidity rate (8.7%-9.6%). No mortality has occurred in any group. The average hospital stay after laparoscopic cholecystectomy was greater when acute cholecystitis was present (2.6 days-4.9 days; p0.01). But in this case hospitalization was shorter than after elective conversion (8 days; p0.001 and p0.05). We conclude that patients with acute cholecystitis can undergo laparoscopic cholecystectomy safely, with low morbidity and mortality rates and reduced hospital stay.

Transcellular chloride transport is the key event underlying epithelial hydration in the intestine. Little is known about the role of protein tyrosine phosphatases in the regulation of basal and stimulated secretion in human intestinal epithelia. The aim of our study was to investigate the effects of the protein tyrosine phosphatase inhibitor sodium orthovanadate on vectorial chloride transport in native human colon.An electrophysiological technique was used to measure changes in short-circuit current via a dual voltage/current clamp in native human colon mucosa and in T84 (ATCC) human intestinal cells mounted in modified Ussing chambers.Orthovanadate (1 mM) added to the serosal side of native human colon caused a net rise in short circuit current, reflecting the stimulation of serosal-to-mucosal chloride movement. Epithelial cells responded similarly to the same concentration of the compound. The stimulatory effect of orthovanadate was enhanced by pretreatment with the tyrosine kinase inhibitor genistein, but only when orthovanadate was added to the basolateral chamber. In contrast, the synergistic interaction did not occur when epithelial cells were previously exposed to the cAMP agonist forskolin.We show that tyrosine phosphatases may be involved in the regulation of epithelial chloride transport, and that orthovanadate stimulates secretion in the human colon.

This research was supported by a grant from FIS96/1443 to M.T. A., DGCYT PB96/0087 to F. G. and FIS94/1405 to J. R.

Laparoscopic antireflux surgery has quickly developed since Bernard Dallemagne carried out the first laparoscopic fundoplication in 1991. However, only preliminary results from institutional series are available. The authors review the indications for laparoscopic antireflux surgery. In addition, technical aspects of several reported laparoscopic antireflux procedures are evaluated. Data from institutional series show that morbidity and mortality rates after laparoscopic antireflux surgery are similar to those reported for open surgery, with a perioperative morbidity rate ranging between 4% and 26% and a mortality rate under 0.6%. Endoscopic dilation for postoperative dysphagia is required in 7%-11% of the cases. In summary, preliminary data show that laparoscopic antireflux surgery may play a predominant role in the treatment of complicated gastroesophageal reflux. Meanwhile, controlled trials with open surgery and medical therapy should be done before the laparoscopic approach is generalized.