Takashi Kobata

Ischemic intestinal involvement in a patient with Buerger disease: Case report and literature review

A 42-year-old Japanese man who had undergone amputation of the left leg below the knee because of Buerger disease required emergency thrombectomy 7 months later. He complained of acute abdominal pain after thrombectomy. At aortography the distal superior mesenteric artery and its branches were not well visualized. Emergency laparotomy was performed because of suspected intestinal ischemia, and the terminal ileum and cecum and part of the ascending colon were resected. In total, the patient underwent laparotomy four times. Histopathologic findings revealed that the arteries and veins of the resected small intestine were occluded with organized thrombi. Inflammatory cell infiltration was recognized mainly in the intima. These findings are compatible with Buerger disease.

Regulation of soluble Flt-1 (VEGFR-1) production by hnRNP D and protein arginine methylation.

Soluble fms-like tyrosine kinase-1 (sFlt-1) functions as a potent inhibitor of angiogenesis by trapping vascular endothelial growth factor (VEGF). However, the precise regulatory mechanism of sFlt-1 production is unknown. Here, we report that vascular sFlt-1 production is regulated by heterogeneous nuclear ribonucleoprotein D (hnRNP D) and arginine methylation. We showed that hnRNP D bound to Flt-1 pre-mRNA and that hnRNP D overexpression decreased sFlt-1 mRNA in human microvascular endothelial cells (HMVECs). In contrast, the reduction of hnRNP D levels induced an increase in sFlt-1 production. Overexpression of an hnRNP D mutant in which the arginine residue of the known arginine methylation motif (arginine-glycine-glycine; RGG) was replaced with alanine did not reduce the level of soluble-form RNA produced from the Flt-1 minigene. Moreover, we demonstrated that overexpression of arginine methyltransferase decreased the soluble-form RNA level, whereas overexpression of arginine demethylase and addition of methyltransferase inhibitors increased sFlt-1 mRNA levels. These findings indicate that hnRNP D and arginine methylation play important roles in the regulation of Flt-1 mRNA alternative polyadenylation.

Externally supported, noncoated, knitted Dacron graft and gelatin-coated knitted Dacron graft with rings for peripheral arterial reconstruction

During the last 14 years, externally supported noncoated knitted Dacron grafts (EXS) and gelatin-coated knitted Dacron grafts with rings (GEL) were used in 176 patients for femoropopliteal bypass (F-P), femorofemoral bypass (F-F) and axillofemoral bypass (Ax-F). In the EXS group, 58 F-P above knee (ak), 42 below knee (bk), 25 F-F, and 19 Ax-F surgeries were performed. Twenty-three F-Pak, 5 F-Pbk, 26 F-F, and 8 Ax-F surgeries were performed in the GEL group. In the F-Pak, primary patency at 5 and 9 years was 75.5 and 53% for the EXS and that at 3 and 5 years was 75.0 and 60.0% for the GEL (n.s.). In the F-Pbk, primary patency at 5 and 10 years was 60.5 and 29.5% for the EXS, while patency at 1 year was 11.1% for the GEL (P<0.05). In both the EXS and the GEL groups, the F-Pak surgery showed better outcomes than the F-Pbk surgery. The outcomes of the F-P grafts implanted into the legs with claudication were better than those performed for the limb salvage cases. Primary patency of the F-F and the Ax-F showed no differences and there were also no differences between the graft types.For F-Pak surgery, the EXS is the graft of choice. The GEL is not suitable for F-Pbk surgery. For F-F and Ax-F reconstruction, both the EXS and the GEL are acceptable.

A Surgical Case of Venous Aneurysm of the Cephalic Vein with Unique Clinicopathological Findings for Venous Dissection: A Possible New Entity

We presented an extremely rare case of a 38-year-old female’s venous aneurysm of left cephalic vein with unique histopathological features, displaying variably thinned medial wall with focal, markedly reduced or absent smooth muscle cells and elastic fibers, most likely leading to the venous dissection with an intimal tear and many medial blood-filled vascular channels. We propose that those venous dissection-like findings would be a new feature especially from the clinicopathological viewpoints and might be considered in the classification of venous aneurysm. Further prospective studies are needed to validate the presence and significance of venous dissecting aneurysm as a new histopathological entity, after collecting and investigating a larger number of venous aneurysm cases examined. This short report could interest the scientific community, taken together with potentially specific findings of new entity, venous dissecting aneurysm.

Replacement of an Infected Prosthetic Graft with an Autogenous Superficial Femoral Vein : A Report of Two Cases

われわれは人工血管感染症例に対して自己下肢深部静脈である浅大腿静脈をグラフトとする非解剖学的再建を2例経験し良好な結果を得た.症例1は75歳,男性.間歇性跛行を主訴とする閉塞性動脈硬化症例に対し,人工血管による大腿-大腿動脈交叉型血行再建を行った.3ヵ月後に局所の発赤と腫脹をきたし,同部に細菌を認めた.症例2は72歳,男性.瘤径5cmの腹部大動脈瘤に対し,Y字人工血管置換術を施行,術後10日目より持続する高熱で発症し,菌血症を認めた.これら保存的加療に抵抗性の2例の人工血管感染に対し,自家の浅大腿静脈による非解剖学的血行再建を行った.ともに大腿深静脈は温存されており,浅大腿静脈採取による静脈鬱滞などの合併症は発症せず,感染は消失しその後経過良好のため退院となった.人工血管感染時の自家組織を用いた血行再建に浅大腿静脈が有用であることを経験し文献的に考察した.