Endoluminal ultrasound for the diagnosis and staging of pancreatic cancer

For pancreatic cancer, endosonography is at present the most accurate method of imaging, especially for detecting small lesions and assessing the extent of locoregional tumour spread. Although the overall accuracy of tumour detection is nearly 100%, differentiation between cancer and pseudotumours of inflammatory origin may sometimes present a problem. Clinical history, symptoms and other imaging techniques, particularly ERCP, should therefore always be considered. On the other hand, endosonography is indicated when the other imaging techniques are negative or doubtful in the presence of a high index of clinical suspicion. In cases with proven malignant tumours, it should be performed for proper staging. The overall accuracy of staging the primary tumour is 80-90%, whereas for detecting lymph nodes it is around 75%. In contrast to angiography, endosonography gives more detailed information of major vessel involvement, an important factor in deciding whether the tumour is resectable. Endosonography is, however, not suitable for the detection of distant metastasis due to the limited penetration of ultrasound. The newly developed echoduodenoscopes, equipped with a working channel and an elevator, provide the possibility for improved accuracy of biopsy under endosonographic guidance, and under clinical evaluation. This should further improve the differentiation between pancreatic cancer and inflammatory pseudotumours, which continues to be a significant clinical problem. So far no procedure-related complications of endosonography have been reported. An adequate experience in conventional ultrasound and endoscopy is essential, however, in order to achieve reliable results.     

Prostatic Artery Embolization with 250-μm Spherical Polyzene-Coated Hydrogel Microspheres for Lower Urinary Tract Symptoms with Follow-up MR Imaging

Purpose

To evaluate clinical outcomes and possible MR imaging predictors of clinical success after prostatic artery embolization (PAE) with 250-μm hydrogel particles.

Effects of growth hormone on renal renin gene expression in normal rats and rats with myocardial infarction.

BACKGROUND: Published data regarding effects of growth hormone (GH) on the renin system are controversial. The aim of this study therefore was to evaluate the effects of GH on the renin system in normal rats and rats with myocardial infarction (MI). METHODS: Normal rats received 2, 5, or 10 IU GH/kg/day or vehicle subcutaneously for 4 weeks. Furthermore rats with MI were randomized to receive 2 IU GH/kg/day or vehicle for 4 weeks. Subdivision into MI groups (mild, moderate, and large) was by histological determination of infarct size. Renal renin gene expression was assessed by RNAase protection assay and plasma renin activity by radioimmunoassay. In addition, isolated mouse juxtaglomerular cells were exposed to GH for 20 h, and renin secretion rates were assessed. RESULTS: GH treatment in normal rats for 4 weeks increased body weight, and kidney weight to body weight ratio, but did not affect renin secretion and renal renin gene expression. In rats with large MI, renal renin gene expression increased about fourfold, but was unchanged in rats with small and moderate MI as compared to normal rats. In rats with MI, body weight decreased and this decrease was partially reversed by GH treatment. GH treatment did not change renal renin gene expression, and renin secretion in rats with MI. Renin secretion of isolated juxtaglomerular cells was unaffected by GH. CONCLUSIONS: Our study demonstrates that GH treatment has no significant effect on renin secretion and on renal renin gene expression in normal rats and in rats with stimulated renin system due to MI in vivo. In isolated juxtaglomerular cells in vitro, renin secretion was also unaffected by GH.     

Integrated Nanosensors to Determine Levels and Functional Activity of Human Telomerase

Telomerase is a key oncogenic enzyme, and a number of novel telomerase inhibitors are currently under development. Because inhibition can be achieved either at the protein or at the enzymatic activity level, independent measurements of these parameters are important in the development of effective therapeutic agents. In the current study, we have developed a set of functional magnetic nanosensors capable of measuring the concentration of telomerase, as well as its enzymatic activity in parallel. The method is based on a magnetic relaxation switch assay, which can be performed in crude tissue samples and is fast and extremely sensitive. Using this method, we were able to detect different amounts of telomerase protein and activity in various cancer and normal cell lines. Furthermore, we were able to study the effect of phosphorylation on telomerase activity. This system not only could provide a rapid assay for the evaluation of antitelomerase therapies but could also be implemented to the study of other cancer markers.     

Efficacy of anticoagulation in resolving left atrial and left atrial appendage thrombi: A transesophageal echocardiographic study

BACKGROUND: Transesophageal echocardiography (TEE) is the gold standard for evaluation of the left atrium and the left atrial appendage (LAA) for the presence of thrombi. Anticoagulation is conventionally used for patients with atrial fibrillation to prevent embolization of atrial thrombi. The mechanism of benefit and effectiveness of thrombi resolution with anticoagulation is not well defined. METHODS AND RESULTS: We used a TEE database of 9058 consecutive studies performed between January 1996 and November 1998 to identify all patients with thrombi reported in the left atrium and/or LAA. One hundred seventy-four patients with thrombi in the left atrial cavity (LAC) and LAA were identified (1.9% of transesophageal studies performed). The incidence of LAA thrombi was 6.6 times higher than LAC thrombi (151 vs 23, respectively). Almost all LAC thrombi were visualized on transthoracic echocardiography (90.5%). Mitral valve pathology was associated with LAC location of thrombi (P <.0001), whereas atrial fibrillation or flutter was present in most patients with LAA location of thrombi. Anticoagulation of 47 +/- 18 days was associated with thrombus resolution in 80.1% of the patients on follow-up TEE. Further anticoagulation resulted in limited additional benefit. CONCLUSIONS: LAC thrombi are rare and are usually associated with mitral valve pathology. Transthoracic echocardiography is effective in identifying these thrombi. LAA thrombi occur predominantly in patients with atrial fibrillation or flutter. Short-term anticoagulation achieves a high rate of resolution of LAA and LAC thrombi but does not obviate the need for follow-up TEE.