Endoscopic treatment of colorectal polyps in a digestive endoscopy outpatient department

The aim of this report was to evaluate the effectiveness of the endoscopic treatment of colonic polyps to allow secondary prophylaxis in order to prevent the onset of cancer arising from adenomas. From October 2002 to January 2004 we performed 487 colonoscopies on a patient group with the following indications: screening prior to kidney transplant; screening for colorectal cancer (patients positive at faecal occult blood testing); follow-up of patients who had undergone colonic resections for colorectal cancer; patients with other diseases. Colorectal polyps were diagnosed in 15 males and 15 females, with a mean age of 63 years. All the neoplasms were resected during colonoscopy and specimens sent for histological study. The histological examinations yielded the following results: 4 hyperplastic polyps; 9 tubular adenomas (6 with mild, 2 with mild-to-moderate, and 1 with severe dysplasia); 8 tubulo-villous adenomas (3 with mild, 1 with mild-to-moderate, and 4 with moderate dysplasia); 4 villous adenomas (3 with mild and 1 with severe dysplasia); 1 adenocarcinoma; 1 inflammatory polyp; in 3 cases we were unable to retrieve the polyps after polypectomy. Colonoscopic detection of a neoplasm allows us to remove it and send to the pathology laboratory for definitive histological diagnosis. Moreover, snare polypectomy can be a radical treatment for dysplastic polyps without stromal axis and basal membrane infiltration. We therefore conclude that colonoscopy allows not only early diagnosis of colonic neoplasms, but also radical curative treatment in the early stages.     

Preliminary experience using the Neuroform stent for the treatment of cerebral aneurysms

INTRODUCTION: The Neuroform microstent-a flexible, self-expandable, microcatheter-delivered, nitinol stent designed for the treatment of cerebral aneurysms-was recently approved for use in patients. We present the results of our initial experience in using the Neuroform stent to treat patients with cerebral aneurysms, with an emphasis on potential applications, technical aspects of deployment, and associated intra- and periprocedural complications. METHODS: The records of all patients treated with the Neuroform stent were entered prospectively into a database. We assessed the clinical history, indications for stent use, aneurysm dimensions, and technical details of the procedures, including any difficulties with stent placement and/or deployment, degree of aneurysm occlusion, and complications. RESULTS: During a 5-month period, 19 patients with 22 aneurysms were treated with the Neuroform stent. Twenty-five stents were deployed. Five patients had multiple stents placed. Five patients had ruptured aneurysms at the time of treatment. The indications for use were broad-necked aneurysms (n = 13; average neck length, 5.1 mm; average aneurysm size, 9 mm), fusiform or dissecting aneurysms (n = 3), salvage and/or bailout (n = 1), and giant aneurysms (n = 2). Technical problems included difficulty in deploying the stent (n = 6), inability to deploy the stent (n = 1), stent displacement (n = 2), inadvertent stent deployment (n = 1), and coil stretching (n = 1). Twenty-one of the 22 aneurysms were treated. Four aneurysms were stented without additional treatment, and 17 aneurysms were stented and coiled. Of the coiled aneurysms, complete or nearly complete (more than 95%) occlusion was achieved in 6 aneurysms, and partial occlusion was achieved in 11. Two clinically significant adverse events occurred, both of which were sequelae of periprocedural thromboembolic complications. One patient died after thrombolysis was attempted. The other patient made an excellent functional recovery after undergoing successful thrombolysis of a thrombosed basilar artery stent. CONCLUSION: The Neuroform stent is a useful device for the treatment of patients with aneurysms that may not otherwise be amenable to endovascular therapy. In the majority of cases, the stent can be deployed accurately, even within the most tortuous segments of the cerebral vasculature. Although delivery and deployment may be technically challenging, clinically significant complications are uncommon.     

In-stent stenosis as a delayed complication of neuroform stent-supported coil embolization of an incidental carotid terminus aneurysm

The Neuroform stent is the first microcatheter-delivered stent designed specifically for the treatment of cerebral aneurysms. The stent functions primarily to provide durable parent vessel protection during the embolization of broad-necked cerebral aneurysms. The present case report demonstrates in-stent stenosis occurring as a delayed complication of Neuroform stent-supported coil embolization of an unruptured cerebral aneurysm.     

Prostate carcinoma and green tea: (-)epigallocatechin-3-gallate inhibits inflammation-triggered MMP-2 activation and invasion in murine TRAMP model

Green tea infusion has been shown to inhibit metastatic spreading of the transgenic adenocarcinoma of mouse prostate (TRAMP). Investigation on the molecular mechanisms triggered by the main green tea flavonoid, (-)epigallocatechin-3-gallate (EGCG), shows that EGCG restrains TRAMP-C1 cell proliferation in a dose-dependent manner, at concentrations (IC(50) < 0.2 microM) equivalent to those measured in the plasma of moderate green-tea drinkers. Up to 10 microM, EGCG does not modify the cell-surface immuno-localization of MMP-2, one of the invasion-instrumental proteinases; but while in default culture conditions these cells secrete mainly pro-MMP-2, in the presence of reconstituted basement membrane (Matrigel) they release almost exclusively pro-MMP-9. In contrast, when stimulated to traverse Matrigel toward a chemo-attractant, in addition to pro-MMP-9, they secrete pro-MMP-2. In the presence of 0.2 microM EGCG, only the level of the latter is markedly lowered in the conditioned medium, in parallel with the invasive behavior (>50%). In vivo, s.c. injection of TRAMP-C1 cells dispersed in Matrigel gives origin to a tumor mass, whose growth is not inhibited by green-tea regimen. This growth is contained greater than two-thirds by LPS-triggered polymorpho-nuclear phagocyte (PMN) recruitment but this effect is abolished by green tea. Nevertheless, while tumor-released pro-MMP-2 is activated by co-incubation of TRAMP-C1 cells with PMNs, in the presence of 10 microM EGCG the activation is almost abolished. These results suggest that inflammatory involvement of prostate carcinoma could be efficaciously prevented by green tea with a concomitant lowering of the invasive potential.     

Biocompatibility assessment of silicone oil and perfluorocarbon liquids used in retinal reattachment surgery in rat retinal cultures

The effects of silicone oil and perfluorocarbon liquids used in retinal reattachment surgery were studied in vitro using rat retinal cultures seeded on microporous inserts. These inserts allow the cell layer to be in contact with the material to be tested on the apical side and with the nutrient medium on the basal side. The materials tested were silicone oil, the perfluorocarbons perfluorophenanthrene and perfluoroctane, and hydroxypropylmethylcellulose. Perfluorophenanthrene, the heaviest of the compounds, induced a very precocious detachment of the cell layer. All the other tested biomaterials were compatible with cell survival and did not alter the structural organization of the retinal cultures, as revealed by scanning electron microscopy. By immunocytochemical techniques we evaluated the cell composition and the differentiation state of each of the cultures. In both control and treated samples, neuronal cells were well preserved. The expression of microtubule-associated protein 2, a marker of differentiated neuronal cytoskeleton, was not affected. Amacrine neurons, immunolabeled for gamma-aminobutyric acid, still were detectable after treatment. Synapses, marked by immunoreactivity for synapthophysin, were equally preserved. Vimentin-positive glial cells did not show modifications. The apoptotic rate, as determined by the terminal transferase-mediated dUTP-biotin nick end-labeling assay, was similar in treated and control samples. The results confirm that the use of biomaterials with a specific gravity close to intraocular fluids is compatible with retinal cell survival and differentiation in vitro.     

Oral contrast agents for magnetic resonance imaging of the bowel

The development of fast imaging sequences, which provide the ability to acquire motion-free T1- and T2-weighted images of static fluids, has greatly increased the interest in magnetic resonance imaging of the small bowel. Luminal distension is a necessary prerequisite for small bowel imaging methods because collapsed bowel loops can hide even large lesions and may mimic wall thickening. Poor distension of normal bowel loops in basal conditions has led researchers to study different oral contrast media to optimally distend the bowel lumen. Several MR oral contrast agents with various signal properties are available. According to these signal properties, agents are classified as positive ("bright" lumen), negative ("dark" lumen), or biphasic ("bright" lumen on T1 and "dark" on T2, or conversely "dark" lumen on T2 and "bright" on T1). Positive contrast agents cause a reduction in T1 relaxation time; consequently, these agents act on T1-weighted images by increasing the signal intensity of the bowel lumen. Negative contrast agents are based on superparamagnetic particles and act by inducing local field inhomogeneities, which results in shortening of both T1 and T2 relaxation times. Using superparamagnetic contrast agents, T2-weighted effects are predominant. Biphasic contrast agents are substances that have different signal intensities on different sequences, depending on the concentration at which they are administered. The choice of a single agent presents advantages and disadvantages; thus, the radiologist should choose the appropriate contrast medium according to the clinical setting, MR experience, availability of the agent, and patient tolerance.     

Lone hepatitis C virus myocarditis responsive to immunosuppressive therapy

OBJECTIVES: This study analyzes the causal role of hepatitis C virus (HCV) in patients with lone myocarditis, and its susceptibility to immunosuppression. BACKGROUND: Prevalence of HCV in lone myocarditis, its mechanism of damage, and possible treatment are still unknown. METHODS: Among 48 consecutive patients with myocarditis serologically screened for HCV and other cardiotropic viruses, 3 patients had anti-HCV antibodies. Clinical manifestation was heart failure in two cases, and left bundle-branch block with moderate cardiac dysfunction was present in patient 3. The three patients underwent two-dimensional echocardiography, coronary angiography, and endomyocardial biopsy. Nested polymerase chain reaction (PCR) for positive and negative strands of HCV on sera and myocardial samples, and PCR for the most common cardiotropic viruses were performed. HCV in the myocardium was detected by TORDJI-22 antibody. RESULTS: At histology, a lymphocytic myocarditis associated with myocytes positively stained by TORDJI-22 was shown in all. Cardiac autoantibodies were detected in all cases. Nested PCR showed both positive and negative strands of HCV RNA in serum and myocardium; other viral genomes were absent. Patients were treated with prednisone and azathioprine for 6 months, with recovery of cardiac volumes and function. At 4-week control biopsy, myocarditis progressed to a healed phase, though HCV RNA was still detectable in the serum and myocardium. Cardiac improvement was maintained at the 12-month overall follow-up. CONCLUSIONS: HCV can be detected in the myocardium of as many as 6% of patients with lone myocarditis; HCV myocarditis can benefit from immunosuppression despite persistence of viral genome, suggesting an immunomediated mechanism of damage.     

Activation of mitogen-activated protein kinases during preparation of vein grafts and modulation by a synthetic inhibitor

OBJECTIVE: Long-term durability of saphenous vein grafts used for coronary artery bypass grafting is limited by neointimal formation. Arterial vascular injury is known to activate intracellular mitogen-activated protein kinases, including extracellular signal-regulated kinases and c-jun N-terminal kinases, that affect cell differentiation, proliferation, migration, and apoptosis. This study tests the hypothesis that these mitogen-activated protein kinases are activated in saphenous veins during preparation for coronary artery bypass grafting. METHODS: Saphenous veins were harvested from 10 patients undergoing coronary artery bypass grafting. A specimen from each vein was placed in ice-cold lysis buffer immediately after harvesting (t = 0). The remaining tissue was incubated at room temperature in normal saline, 0.1% dimethylsulfoxide (vehicle), or 50 mmol/L PD98059 (mitogen-activated protein kinase kinase-1/2 inhibitor) until the vein was grafted (mean 50 minutes). To study kinetics of intracellular signaling pathways, canine saphenous veins were harvested, and mitogen-activated protein kinases and PI-3 kinase pathways were studied after different incubation time intervals. Extracted proteins were analyzed by Western blotting or in vitro kinase assay. RESULTS: The human saphenous veins showed elevated levels of active extracellular signal-regulated kinase after harvesting (t = 0) and prior to implant (t = 1). Incubation with PD98059 resulted in decreased activation of extracellular signal-regulated kinase. Kinetics of canine saphenous veins showed extracellular signal-regulated kinase and c-jun N-terminal kinase activation, in a time-dependent manner, along with activation of the growth factor-regulated PI3 kinase pathway. CONCLUSIONS: This study characterizes activation of extracellular signal-regulated kinases and c-jun N-terminal kinases during vein graft preparation and demonstrates the ability to inhibit extracellular signal-regulated kinase activation by simple incubation with a specific inhibitor. Further studies are needed to evaluate the significance of these findings with respect to graft durability.