Atsushi Seyama

Neovascularization induced by autologous bone marrow cell implantation in peripheral arterial disease.

Neovascularization has recently been used as a new treatment for severe ischemic disease. We tried to induce therapeutic neovascularization by autologous bone marrow cell implantation (BMCI) in eight selected patients with chronic peripheral arterial disease (PAD), in whom traditional treatments had failed. Improvement of subjective symptoms was seen in seven patients after treatment. Of three limbs with toe or finger ulceration, complete healing was achieved in two, while the other one became less severe after treatment. No relative toxicity was observed in any of the patients. BMCI might be a feasible treatment for selected patients with chronic PAD.

The Role of Oxygen-Derived Free Radicals and the Effect of Free Radical Scavengers on Skeletal Muscle Ischemia/Reperfusion Injury

The aim of this study was to clarify the role of oxygen-derived free radicals and the effect of free radical scavengers on skeletal muscle ischemia/reperfusion injury. Male Wistar rats were divided into a complete ischemia group (C-group) and an incomplete ischemia group (IC-group) and each animal was subjected to 2h of ischemia and 1h of reperfusion. In an attempt to decrease reperfusion injury, the rats were given free radical scavengers either as allopurinol 50 mg/kg for 2 days or as superoxide dismutase 60,000 units/kg plus catalase 500,000 units/kg. Tissue malondialdehyde, a product of lipid peroxidation, was measured as an indicator of free radicals, with higher levels indicating higher concentrations of free radicals. The malondialdehyde level in the gastrocnemius muscle after 1h of reperfusion increased significantly in both groups when compared to the levels before and 2h after ischemia, although there was no significant difference between the two groups. The water content of the gastrocnemius muscle and serum creatinine phosphokinase MM isoenzyme (CPK-MM) in both groups, and GOT in the C-group, increased significantly after 1h of reperfusion when compared the values before and 2h after ischemia. In the C-group, these values were significantly higher than in the IC-group. The administration of free radical scavengers suppressed the increase in malondialdehyde in the gastrocnemius muscle after reperfusion in both groups. The increase in water content and CPK-MM after reperfusion was also suppressed by free radical scavengers in the IC-group, but not in the C-group. These findings suggest that ischemic damage predominates in complete severe ischemia/reperfusion injury, whereas reperfusion injury predominates in incomplete mild ischemia/reperfusion injury.

Laparoscopic resection of an ileal lipoma : Report of a case

A 63-year-old woman was admitted to our hospital for investigation of upper abdominal pain and vomiting. Ultrasonography (US) showed a hyperechoic mass in the right lower abdomen, and computed tomography (CT) showed a low-density mass and intestinal invagination. Thus, we made a diagnosis of intestinal lipoma with intussusception and performed laparoscopic partial resection of the ileum, including the tumor. The resected specimen contained a round tumor, 25 × 22 × 20 mm, which was identified as an intestinal lipoma histopathologically. Our experience supports earlier reports that US and CT are effective tools in the diagnosis of bowel lipoma. Laparoscopic surgery is the treatment of choice for benign tumors of the small intestine because it is minimally invasive, with cosmetic, physical, and economic benefits.

Laparoscopic cecopexy for mobile cecum syndrome manifesting as cecal volvulus: Report of a case

A 44-year-old woman was admitted to our hospital for investigation and treatment of sudden abdominal pain and distention. Plain abdominal radiography and abdominal computed tomography (CT) findings were suggestive of sigmoid volvulus. She underwent an emergency colonoscopy, and the scope passed easily through the sigmoid colon and reached the ascending colon quickly. However, stenosis with concentricity of the fold was observed in the cecum, which was shifted upward and to the left. Based on these findings, we diagnosed cecal volvulus caused by mobile cecum syndrome. The patient’s symptoms resolved quickly after colonoscopic reduction and elective laparoscopic surgery was performed 18 days after admission. Perioperative examination revealed a mobile cecum caused by an elongated ascending colon. We sutured the cecum and ascending colon to the lateral peritoneum laparoscopically with interrupted sutures. The patient recovered well and was discharged on postoperative day 7. An unfixed intestine can be detected easily during laparoscopic surgery, which is minimally invasive and cosmetically, physically, and economically beneficial. Thus, we recommend laparoscopic cecopexy for mobile cecum syndrome.

Shock-reinfusion injury to the central organs and the effect of free radical scavengers in the rat

Hemorrhagic shock-reinfusion injury produces critical changes in various organs with the generation of oxidant-free radicals. Some papers have reported that shock-reinfusion injury to the intestine is effectively reduced by the scavengers of free radicals; however, few reports mention the central organ damage caused by systemic hemorrhagic shock-reinfusion injury. Using a rat systemic hemorrhagic shock model, injury to the central organs, being the brain, heart, lungs, liver, and kidneys was assessed by measuring malondialdehyde (MDA). The MDA levels in the lungs, kidneys, and liver were elevated significantly after reinfusion, although there was no elevation of MDA in the brain or heart. These data show that the lungs, liver, and kidneys are easily damaged by shock-reinfusion, but that the brain and heart are relatively resistant. The efficacy of the free radical scavengers, superoxide dismutase plus catalase and allopurinol, were evaluated 30 min after reinfusion. Pathological examination showed that superoxide dismutase plus catalase and allopurinol reduced reinfusion injury in the lungs, liver, and kidneys. Moreover, superoxide dismutase plus catalase reduced MDA levels in both the liver and kidneys, whereas allopurinol reduced MDA levels only in the kidneys after reinfusion. However, these free radical scavengers could not suppress the elevation of MDA in the lungs after reinfusion.

Early laparoscopic cholecystectomy for acute gangrenous cholecystitis.

Treatment of severe acute cholecystitis by laparoscopic cholecystectomy remains controversial because of technical difficulties and high rates of complications and conversion to open cholecystectomy. We investigated whether early laparoscopic cholecystectomy is appropriate for acute gangrenous cholecystitis. Pathologic diagnoses and outcomes were analyzed in patients who underwent laparoscopic or open cholecystectomy at our hospital, January 2002 to September 2005. Of 30 patients with acute gangrenous cholecystitis, 16 underwent early laparoscopic cholecystectomy, 10 underwent open cholecystectomy, and 4 were converted to open cholecystectomy (conversion rate, 20.0%). There was no significant difference in operation time or intraoperative bleeding. The requirement for postoperative analgesics was significantly lower (6.4±7.3 vs. 1.5±1.2 doses, P<0.05) and hospital stay significantly shorter (8.6±2.1 vs. 15.6±6.3 d, P<0.01) after laparoscopic cholecystectomy. There were no postoperative complications in either group. Thus, early laparoscopic cholecystectomy seems appropriate for acute gangrenous cholecystitis. Conversion to open cholecystectomy may be required in difficult cases with complications.

Microvascular transport is associated with TNF plasma levels and protein synthesis in postischemic muscle

To better understand the mechanisms of ischemia-reperfusion (I/R) injury, we tested the hypothesis that protein synthesis is involved in the production of tumor necrosis factor (TNF) and in the microvascular transport changes in I/R. To evaluate the hypothesis, we inhibited protein synthesis with topically applied actinomycin D (AMD), measured I/R-induced changes in microvascular transport, and bioassayed the venous plasma levels of TNF. The rat cremaster muscle I/R model consisted of 4 h of ischemia followed by 2 h of reperfusion. Changes in transport were determined by integrated optical intensity (IOI) using FITC-Dextran 150 as tracer. Animals were separated into four groups: 1) control (C), 2) control treated with AMD (C + AMD), 3) I/R, and 4) I/R treated with AMD (I/R + AMD). The mean (+/-SE) maximal IOI in C and C + AMD were 3.0 +/- 1.0 and 3. 7 +/- 0.7 units, respectively. I/R elevated mean maximal IOI to 21.8 +/- 1.9 units (P < 0.05 vs. C, C + AMD, I/R + AMD). Treatment with AMD reduced the I/R-induced mean maximal IOI to 9.7 +/- 2.0 units (P < 0.05 vs. I/R). In I/R group, plasma TNF levels increased (relative to preischemia baseline) immediately after the release of the vascular occlusion to 250 pg/ml and reached a peak value of 342 pg/ml at 60 min of reperfusion. In the I/R + AMD group, AMD reduced TNF increase to 44 pg/ml. The C and C + AMD groups showed no differences in TNF values during the 6 h of observation. We conclude that protein synthesis and TNF generation are at least partially involved in I/R-induced changes in microvascular transport.To better understand the mechanisms of ischemia-reperfusion (I/R) injury, we tested the hypothesis that protein synthesis is involved in the production of tumor necrosis factor (TNF) and in the microvascular transport changes in I/R. To evaluate the hypothesis, we inhibited protein synthesis with topically applied actinomycin D (AMD), measured I/R-induced changes in microvascular transport, and bioassayed the venous plasma levels of TNF. The rat cremaster muscle I/R model consisted of 4 h of ischemia followed by 2 h of reperfusion. Changes in transport were determined by integrated optical intensity (IOI) using FITC-Dextran 150 as tracer. Animals were separated into four groups: 1) control (C), 2) control treated with AMD (C + AMD), 3) I/R, and 4) I/R treated with AMD (I/R + AMD). The mean (±SE) maximal IOI in C and C + AMD were 3.0 ± 1.0 and 3.7 ± 0.7 units, respectively. I/R elevated mean maximal IOI to 21.8 ± 1.9 units ( P < 0.05 vs. C, C + AMD, I/R + AMD). Treatment with AMD reduced the I/R-induced mean maximal IOI to 9.7 ± 2.0 units ( P< 0.05 vs. I/R). In I/R group, plasma TNF levels increased (relative to preischemia baseline) immediately after the release of the vascular occlusion to 250 pg/ml and reached a peak value of 342 pg/ml at 60 min of reperfusion. In the I/R + AMD group, AMD reduced TNF increase to 44 pg/ml. The C and C + AMD groups showed no differences in TNF values during the 6 h of observation. We conclude that protein synthesis and TNF generation are at least partially involved in I/R-induced changes in microvascular transport.

Plethysmographic Evaluation of Venous Function

It is widely recognized that venous hypertension is generated by a combination of valvular incompetence, venous obstruction, and calf muscle pump dysfunction. The status of the deep and superficial veins in both the proximal and distal segments can have significant impact on the success of perforator vein surgery. Prior to operation, detailed knowledge of the pattern of venous obstruction and incompetence can help establish the likelihood of successful treatment. Postoperative assessment may uncover the changes in limb hemodynamics affected by perforator ligation.

Assessment of Laser Doppler Flowmetry During Abdominal Aortic Aneurysmectomy

The purpose of the present study was to assess the diagnostic utility of blood flow measurements at the sigmoid colon by laser Doppler flowmetry. Methods: A laser-Doppler flow probe was placed in contact with the serosa of the sigmoid colon in 41 patients undergoing resection of infrarenal abdominal aortic aneurysms. Blood flows were measured before aortic clamping, after reconstruction, and after inferior mesenteric artery revascularization. Results: The authors observed a colonic blood flow greater than 18 mL/minute/100 g in all the patients who did not develop postoperative ischemic colitis. Conclusions: The colonic blood flow needed to prevent postoperative ischemic colitis is greater than 18 mL/minute/100 g. The assessment of blood flow at the sigmoid colon by laser Doppler flowmetry is useful for predicting postoperative ischemic colitis.

Small-Caliber Arterial Anastomosis Using a CO2 Laser

The present study was designed to determine whether the use of CO2 laser irradiation could effectively maintain long-term patency in small-caliber arteri al anastomoses less than 3 mm in diameter. A preliminary study was conducted to examine the relationship between laser energy and histologic changes. The laser output of 30 to 40 mW produced a less inflammatory response, than 50 mW did and almost normal aortic architecture one month after the exposure. Therefore, a 30 to 40 mW range, over a twenty-second period, was seen as a suitable laser energy. Arterial anastomoses using a CO2 laser were performed (12 rabbits) with a suitable laser energy. Conventional anastomoses were per formed as controls (12 rabbits). The operation times, patency rate, and histo logic changes were compared in both groups at one week and at one, three, and six months after anastomoses. The anastomotic time was shorter in the laser anastomosis group than that in the control group. The patency rate was equal in both groups. However, the conventional anastomosis group revealed slight intimal hyperplasia at six months, whereas the laser anastomosis group showed almost normal neointimal development. It was hence concluded that CO2 laser welding of the anastomosis is an acceptable alternative to conventional anastomosis.