PubMed Health⌕ Search

Biomedical subjects

Jeffrey Cohen

Publications and source records attributed to Jeffrey Cohen.

23 records · Page 2Linked to original sources

The changing paradigm for the treatment of colonic hemorrhage: superselective angiographic embolization.

PURPOSE: Colonic bleeding has historically been controlled by the use of localization procedures and surgery. Since our initial experience with superselective embolization of colonic bleeding, it has become our preferred method for the control of lower gastrointestinal hemorrhage. This follow-up study evaluates the Hartford Hospital experience using angiographic methods as the primary modality for the treatment of colonic bleeding. METHODS: From March 1993 to September 1999, 27 patients who had angiographically visualized colonic hemorrhage underwent arterial embolization procedures. Diagnostic arteriography was performed in all patients using digital subtraction imaging and selective contrast injections into the superior and inferior mesenteric arteries. Once the bleeding site was identified, superselective arteriogram and embolization was performed. Platinum-fibered coils, Hilal coils, or polyvinyl alcohol particle emboli were then fluoroscopically guided into the bleeding vessel. A repeat arteriogram was performed to confirm occlusion and the absence of any collateral channels. RESULTS: All 27 patients were initially controlled with arterial embolization; 6 patients rebled (22.2 percent), and 5 of these patients required surgery. Two patients demonstrated ischemia (7.4 percent), one of which required surgical intervention. The other patient was followed up by colonoscopy. There was no mortality in this study. CONCLUSION: Superselective embolization is effective in controlling colonic hemorrhage and is associated with a low rate of postembolization ischemia. Our experience with angiography reinforces the paradigm shift from its use as a diagnostic tool to the primary method for the control of colonic bleeding. Because patients have been followed up for as long as seven years, this approach remains effective for the long-term treatment of colonic bleeding.

Adult↗

Cryosurgical ablation of renal tumors using 1.5-millimeter, ultrathin cryoprobes.

INTRODUCTION: To describe an open technique for the cryosurgical ablation of small renal tumors using multiple ultrathin cryoprobes. Renal cryosurgery is an evolving surgical technique, and uncertainties exist regarding the ideal approach to freezing renal tumors. TECHNICAL CONSIDERATIONS: Using an open surgical approach, a 3-cm upper pole renal mass was ablated using five, state-of-the-art, 1.5-mm cryoprobes simultaneously under real-time ultrasound guidance. The technique is described and demonstrated in a multisegment, Internet-based video tutorial. The blood loss was minimal, and no intraoperative or postoperative complications were experienced. Follow-up imaging at 3 months suggested shrunken, nonviable tumor. CONCLUSION: Cryosurgical ablation of renal tumors using multiple 1.5-mm cryoprobes is a safe, feasible approach that may be associated with a decreased risk of bleeding.

Adenocarcinoma, Clear Cell↗

Psychological research online: report of Board of Scientific Affairs' Advisory Group on the Conduct of Research on the Internet.

As the Internet has changed communication, commerce, and the distribution of information, so too it is changing psychological research. Psychologists can observe new or rare phenomena online and can do research on traditional psychological topics more efficiently, enabling them to expand the scale and scope of their research. Yet these opportunities entail risk both to research quality and to human subjects. Internet research is inherently no more risky than traditional observational, survey, or experimental methods. Yet the risks and safeguards against them will differ from those characterizing traditional research and will themselves change over time. This article describes some benefits and challenges of conducting psychological research via the Internet and offers recommendations to both researchers and institutional review boards for dealing with them. ((c) 2004 APA, all rights reserved)

Advisory Committees↗

Placental growth factor provides a novel local angiogenic therapy for ischemic cardiomyopathy.

BACKGROUND: Heart failure occurs predominantly due to coronary artery disease and may be amenable to novel revascularization therapies. This study evaluated the effects of placental growth factor (PlGF), a potent angiogenic agent, in a rat model of ischemic cardiomyopathy. METHODS: Wistar rats underwent high proximal ligation of the left anterior descending coronary artery and direct injection of PlGF (n = 10) or saline as a control (n = 10) into the myocardium bordering the ischemic area. After 2 weeks, the following parameters were evaluated: ventricular function with an aortic flow probe and a pressure/volume conductance catheter, left ventricular (LV) geometry by histology, and angiogenesis by immunofluorescence. RESULTS: PlGF animals had increased angiogenesis compared to controls (22.8 +/- 3.5 vs. 12.4 +/- 3.2 endothelial cells/high-powered field, p < 0.03). PlGF animals had less ventricular cavity dilation (LV diameter 8.4 +/- 0.2 vs. 9.2 +/- 0.2 mm, p < 0.03) and increased border zone wall thickness (1.85 +/- 0.1 vs. 1.38 +/- 0.2 mm, p < 0.03). PlGF animals had improved cardiac function as measured by maximum LV pressure (95.7 +/- 4 vs. 73.7 +/- 2 mmHg, p = 0.001), maximum dP/dt (4206 +/- 362 vs. 2978 +/- 236 mmHg/sec, p = 0.007), and ejection fraction (25.7 +/- 2 vs. 18.6 +/- 1%, p = 0.02). CONCLUSIONS: Intramyocardial delivery of PlGF following a large myocardial infarction enhanced border zone angiogenesis, attenuated adverse ventricular remodeling, and preserved cardiac function. This therapy may be useful as an adjunct or alternative to standard revascularization techniques in patients with ischemic heart failure.

Angiogenesis Inducing Agents↗