A scanning electron microscope study of surface features of viral and spontaneous transformants of mouse Balb-3T3 cells.

Cells of the mouse line Balb/3T3 as well as three virus-induced transformants and two spontaneous transformants grown in vitro have been studied for their topography by scanning electron microscopy. The parent cell in confluent culture closely resembles an endothelial cell in its form and in the structure of its association with adjacent cells. The tumorigenic transformants produced by SV40, murine sarcoma virus, or polyoma viruses are fusiform to pleomorphic and distinctly different from the cell of origin. They show relatively smooth surfaces except for blebs and marginal microvilli. Perhaps most surprising is the similarity they bear to one another. This is made the more singular by the very different form shown by the tumorigenic transformants of spontaneous origin. One of these, S2-4, possesses a thickened rather than the lamellar form of the parent A31 cell and is covered by long microvilli and many spherical blebs. The other, TuT(3), more closely resembles the cell of origin but shows extensive ruffling at its margins. All transformants grow without evidence of contact inhibition. The significance of the surface morphologies and the factors influencing cell form are discussed.

Visualization of fibrillar amyloid deposits in living, transgenic Caenorhabditis elegans animals using the sensitive amyloid dye, X-34.

Transgenic Caenorhabditis elegans animals can be engineered to express high levels of the human beta amyloid peptide (Abeta). Histochemistry of fixed tissue from these animals reveals deposits reactive with the amyloid-specific dyes Congo Red and thioflavin S (Fay et al., J. Neurochem 71:1616, 1998). Here we show by immuno-electron microscopy that these animals contain intracellular immunoreactive deposits with classic amyloid fibrillar ultrastructure. These deposits can be visualized in living animals using the newly developed, intensively fluorescent, amyloid-specific dye X-34. This in vivo staining allows monitoring of amyloid deposition in individual animals over time. The specificity of this staining is demonstrated by examining transgenic animals expressing high levels of a non-fibrillar beta peptide variant, the beta single-chain dimer. These animals have deposits immunoreactive with anti-beta antibodies, but do not have X-34 deposits or deposits with a fibrillar ultrastructure. X-34 can also be used in vivo to visualize putative amyloid deposits resulting from accumulation of human transthyretin, another amyloidic protein. In vivo amyloid staining with X-34 may be a useful tool for monitoring anti-amyloidic treatments in real time or screening for genetic alterations that affect amyloid formation.

Virtual endoscopy: already a feasible proposition or a future prospect in diagnostics? A review of the literature.

The aim of this article was to carry out a retrospective analysis of the feasibility of using virtual endoscopy in the field of gastrointestinal diseases. After a retrospective review of the international literature the authors analyse the most controversial aspects of virtual endoscopy such as its effective diagnostic reliability and potential clinical employment with specific reference to diagnosing colon diseases. The international literature shows that virtual endoscopy is currently poorly sensitivity in detecting lesions measuring less than 10 mm in diameter and that the radiologist's experience can negatively condition the trustworthiness of this procedure. Virtual endoscopy is likely to be the future gold standard in the field of diagnostic imaging. Furthermore, it eliminates all the compliance-related problems and any risk of iatrogenic lesions such as perforations and bleedings which are typical of traditional endoscopy. Its current sensitivity, however, is poor and it is unable to detect lesions smaller than 10 mm. Its reliability therefore needs to be improved.

[Ambulatory surgery: preoperative assessment]. / Chirurgia ambulatoriale: la valutazione preoperatoria.

Over the past 20 years public health expenditure has progressively increased for various reasons. With the aim of reducing public health expenditure and hospital stays, alternative models of public health care have been more widely adopted over the past two decades: Day Hospital, day surgery and ambulatory surgery. What is meant by ambulatory surgery is the clinical, organisational and administrative possibility of performing surgical operations and/or invasive and semi-invasive diagnostic procedures without hospitalisation of patients, in doctors' surgeries, outpatient departments or protected outpatient facilities. For both the patients and the centres providing the service to be able to exploit all the advantages stemming from this kind of health care provision, careful patient selection is mandatory, including assessment of the impact of any potential concomitant pathologies. Starting from their own personal experience and existing reports in the international literature, the authors analyse the impact that concomitant pathologies may have on patient selection for ambulatory surgery. The authors conclude that thorough preoperative evaluation of all the possible variables involved is the only way of ensuring the success of ambulatory surgery.

[Mixed carcinoid-adenocarcinoma tumor of the appendix: a case report and diagnostic and therapeutic considerations]. / Tumore misto carcinoide-adenocarcinoma dell'appendice: caso clinico e considerazioni diagnostico-terapeutiche.

The layout of the work has stayed motivated from the recent observation of mixed carcinoid, located to the appendix and wide to the peritoneal cable, joint to our observation in an elderly patient with aspecific demonstration clinical-symptomatologic. The study of the endocrine tumors is in continuous evolution also if, to the actual state, there is a better comprehension of this neoplasm, variegated and complex and, under some appearances, still not known well. Jejunoileal carcinoid tumors differ, under many appearances, from those occurring in other sites of the gut. They have relatively high rate of transmural invasion and aggressive clinical behavior, contrasted by a scarce objectivity; the demonstration of symptoms generally implicates the presence of an illness in advanced stage. Also pharmacological therapy made important progress, with the possibility of administer composed able to interfere with the development and the neoplastic growth.

Gastro-intestinal stromal tumor (GIST): case report.

Gastro-intestinal stromal tumors (GISTs), as currently defined, represent the largest category of primary non epithelial neoplasms of the gastrointestinal tract. They arise from mesenchymal cells located in the wall of the organ and show a remarkable variability in their differentiation pathways. For this reason there is relevant degree of confusion in their interpretation. On the basis of immunohistochemical and ultrastructural studies these neoplasms are divided into several categories: leiomyomas, schwannomas and less differentiated tumors referred as GIST. In the small bowel GIST are uncommon. Usually asymptomatic, they could be the cause of surgical emergencies like massive bleeding, obstruction, intussusception or perforation. Generally benign, an higher percentage of malignant cases are described in the small bowel. The Authors report a case of malignant GIST of the small intestine presented with bowel obstruction by ileal invagination. In this case, as usually it happens in malignant GIST, the final diagnosis was obtained by an abdominal surgical exploration.