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Abstract Background We previously showed that the envelope (env) sequence of a human endogenous retrovirus (HERV)-W locus on chromosome Xq22.3 is transcribed in human peripheral blood mononuclear cells. The env open reading frame (ORF) of this locus is interrupted by a premature stop at codon 39, but otherwise harbors a long ORF for an N-terminally truncated 475 amino acid Env protein, starting at an in-frame ATG at codon 68. We set out to characterize the protein encoded by that ORF. Results Transient expression of the 475 amino acid Xq22.3 HERV-W env ORF produced an N-terminally truncated HERV-W Env protein, as detected by the monoclonal anti-HERV-W Env antibodies 6A2B2 and 13H5A5. Remarkably, reversion of the stop at codon 39 in Xq22.3 HERV-W env reconstituted a full-length HERV-W Xq22.3 Env protein. Similar to the full-length HERV-W Env protein Syncytin-1, reconstituted full-length Xq22.3 HERV-W Env is glycosylated, forms oligomers, and is expressed at the cell surface. In contrast, Xq22.3 HERV-W Env is unglycosylated, does not form oligomers, and is located intracellularly, probably due to lack of a signal peptide. Finally, we reconfirm by immunohistochemistry that monoclonal antibody 6A2B2 detects an antigen expressed in placenta and multiple sclerosis brain lesions. Conclusions A partially defective HERV-W env gene located on chromosome Xq22.3, which we propose to designate ERVWE2, has retained coding capacity and can produce ex vivo an N-terminally truncated Env protein, named N-Trenv. Detection of an antigen by 6A2B2 in placenta and multiple sclerosis lesions opens the possibility that N-Trenv could be expressed in vivo. More generally, our findings are compatible with the idea that defective HERV elements may be capable of producing incomplete HERV proteins that, speculatively, may exert functions in human physiology or pathology.

Purpose: Hypogastric artery embolization is considered to be necessary to prevent retrograde flow and potential endoleaks when a stent-graft crosses the origin of the hypogastric artery. The authors assess the incidence of buttock claudication, which is the primary complication encountered. The effect of coil location and the presence of antegrade flow at the completion of embolization are evaluated., Materials and Methods: Hypogastric artery embolization and endoluminal repair of aneurysms and fistulas was performed in 34 patients (30 men; four women) aged 27-91 years (mean, 76 years). Ten patients were being treated for solitary abdominal aortic aneurysms, 13 were being treated for aortoiliac aneurysms, and six patients were being treated for isolated common iliac aneurysms, three for hypogastric artery aneurysms and two for iliac arteriovenous fistulas. Eleven patients had coils placed completely above the bifurcation of the hypogastric artery and 23 patients had coils placed at the bifurcation, or within the branches of the hypogastric artery. Preservation of antegrade flow after embolization was noted in 14 of 34 patients., Results: Thirty-four patients underwent stent-graft repair after hypogastric artery embolization. There were two perioperative deaths, three proximal leaks, and one collateral leak. Of the 32 patients who survived the procedure, there was one retrograde leak, even though 13 of 32 (41%) patients had continued antegrade flow at completion of the hypogastric artery embolization. When coils were placed at or in the bifurcation of the hypogastric artery, 12 of 22 (55%) experienced claudication. When coils were placed in the proximal hypogastric artery, one of 10 (10%) claudicated., Conclusion: It is probably not necessary to completely occlude antegrade flow in the hypogastric artery to prevent a distal endoleak. Buttock claudication is rare when coils are placed in the proximal hypogastric artery rather than at its bifurcation or in its branches.

Background: Intra-arterial thrombolytic therapy is currently a therapeutic option for the treatment of acute limb ischemia. A recent large prospective randomized trial (TOPAS) comparing lytic therapy and operative intervention showed that both forms of treatment had similar results in terms of amputation-free survival. However, the exact role for lytic treatment is unclear., Method: Over a 4-year period we treated 60 cases of acute limb ischemia in 57 patients secondary to native artery occlusion with thrombolytic therapy with urokinase. All patients were evaluated at 1 week, 1 month, and then at 3-month intervals posttreatment. Follow-up evaluations included pulse examination, pulse volume recordings, and duplex examinations to confirm arterial patency. No patients were lost to follow-up with a range of 8 to 54 months (mean 26)., Results: Of these 60 native arterial occlusions, complete lysis was achieved in 46 cases (76%). Of these 46 cases, 18 required lysis only, 19 cases (9 iliac, 7 superficial femoral artery (SFA), and 3 popliteal) required angioplasty of lesions uncovered by clot lysis, and 9 patients had lysis and angioplasty of iliac arteries followed by infrainguinal bypasses. Eight of the 57 patients (14%) who had been asymptomatic presented with symptoms limited to new onset claudication, all of which were successfully lysed. Cumulative patency for the 43 successful cases was 90% +/- 5% at 1 year and 75% +/- 4% at 2 years. The 1-year amputation-free survival for all native artery occlusions was 85% +/- 6%., Conclusion: Thrombolysis with urokinase simplified the treatment of native arterial occlusion proving to be the sole therapy in 18 (29%) patients or a valuable adjunct by facilitating the angioplasty of arterial lesions and avoiding open surgery in 60% of patients treated. In addition, the correction of inflow lesions reduced the magnitude of required subsequent bypass procedures to achieve limb salvage. In conclusion, successful thrombolysis of native artery occlusion provided durable arterial patency and limb salvage, particularly in patients with new onset claudication.

Purpose: Significant disease or occlusion of the common femoral artery may preclude percutaneous therapy for aorto-iliac occlusive disease. In addition, aorto-iliac angioplasty may not reverse the ischemic symptoms when common femoral artery disease exists. The authors describe the feasibility of endoluminal stent-grafts to treat multilevel aortoiliofemoral occlusive disease., Materials and Methods: The authors placed 18 stent-grafts for aorto-iliac occlusive disease in 17 patients with limb-threatening ischemia and significant common femoral artery disease. These procedures were performed as a joint effort between vascular surgery and interventional radiology staff in the operating room. The common femoral artery was occluded in 10 or severely diseased in eight, necessitating endoluminal bypass to the superficial femoral or popliteal artery (n = 7) or to the deep femoral artery (n = 7), or necessitating patch angioplasty of the common femoral artery (n = 4). Stent-grafts were fabricated from 6-mm polytetrafluoroethylene and 29-mm Palmaz stents., Results: All 18 grafts were placed successfully. Follow-up ranged from 3 to 38 months (mean, 21 months). Seven patients died of myocardial infarction; two grafts occluded and one required angioplasty during follow-up, resulting in a primary patency rate of 81% at 2 years., Conclusion: Endoluminal stent-graft placement is a useful method of treatment for advanced atherosclerotic aorto-iliac disease, particularly in the presence of common femoral artery disease. This approach avoids an extra-anatomic bypass or a major transabdominal aortic bypass procedure. Longer follow-up with a larger series is needed to ensure the safety and late graft patency comparable to the traditional aortofemoral and iliofemoral bypass grafts.

Objective: Transfemorally placed endoluminal grafts are currently being evaluated as an alternative to open surgery for the treatment of abdominal aortic aneurysms. We determined the value of helical CT for the follow-up of patients treated with this new procedure. The purposes of this study were to determine CT features of a technically successful procedure, detect complications, and compare findings on CT scans obtained 24-48 hr after insertion of the graft with findings on angiograms obtained at the end of the endovascular procedure., Subjects and Methods: Seven patients with large abdominal aortic aneurysms had helical CT within 48 hr after transfemoral insertion of an endoluminal graft. Findings on these CT scans were compared with findings on digital completion angiograms obtained immediately after placement of the graft. Additional follow-up CT scans were obtained for up to 15 months (mean, 8 months). The size of the aneurysmal sac; completeness of perigraft thrombosis; and position, shape, and patency of the device were recorded., Results: CT scans obtained 24-48 hr after placement of the grafts showed complete thrombosis of the aneurysmal sac in three patients and incomplete thrombosis with patent perigraft channels in the four remaining patients. Angiograms showed a patent perigraft channel in only one patient. Two of four initially patent channels subsequently closed, but one of them recurred. Of four thrombosed aneurysms, two decreased in size, and two were unchanged on later follow-up. Of three aneurysms associated with perigraft channels, two became enlarged and one was stable. On the basis of CT criteria, successful endovascular repair was shown in four (57%) of seven patients., Conclusion: Helical CT is a sensitive means of evaluating the efficacy of endoluminal grafts. Decreased or stable size of the aneurysmal sac without perigraft channels on late follow-up CT signifies technical success. Persistence or recurrence of perigraft channels is the most likely cause of later enlargement of an aneurysm and therefore suggests procedural failure. Helical CT was more sensitive than angiography for detection of perigraft channels that occurred soon after treatment.