Mitsuaki Sadahiro

Enhancement of heat shock protein expression after transient ischemia in the preconditioned spinal cord of rabbits.

PURPOSE This investigation was designed to evaluate the mechanism used to acquire a tolerance to spinal ischemia. We investigated inductions of the heat shock protein (HSP) 70 gene and protein in rabbit spinal cord with or without preconditioning. METHODS Neurologic function, morphologic changes, and inductions of HSP70 messenger RNA (mRNA) and protein were compared in the cases of a 15-minute ischemia 2 days after sham treatment and a 15-minute ischemia 2 days after 10-minute preconditioning. RESULT HSP70 mRNA was induced at 8 hours of reperfusion after a 15-minute ischemia 2 days after sham treatment. HSP70 protein was induced slightly in selective motor neuron cells at 8 hours of reperfusion, and about 70% of motor neuron cells showed selective cell death after 7 days of reperfusion (p < 0.01). On the other hand, large populations of the motor neuron cells survived at 7 days after the 15-minute ischemia that was applied at 2 days after preconditioning (p < 0.01). HSP70 mRNA was induced persistently as compared with the case of a 15-minute ischemia 2 days after sham treatment. The motor neuron cells strongly produced immunoreactive HSP70 from 8 hours to 2 days. CONCLUSION Preconditioning with 10-minute ischemia enhanced and prolonged the HSP70 gene expression at both mRNA and protein levels and saved the motor neuron cells from subsequent lethal ischemia. These changes of HSP70 gene expression may play an important role in the acquisition of ischemic tolerance of motor neuron cells in rabbit spinal cord.

Anatomic thoracoscopic pulmonary segmentectomy under 3-dimensional multidetector computed tomography simulation: A report of 52 consecutive cases

OBJECTIVE The purpose of this retrospective study was to evaluate the efficacy of anatomic thoracoscopic pulmonary segmentectomy performed under the guidance of 3-dimensional multidetector computed tomography simulation. METHODS Between September 2004 and June 2009, 52 patients (median age, 68 years; range, 16-85 years) underwent thoracoscopic segmentectomy without mini-thoracotomy. Images were obtained by using 64-channel multidetector computed tomography and a contrast agent. The pulmonary arteriovenous structure was mainly determined using a 3-dimensional volume-rendering method. The preoperative simulation was performed at the initial stage of the study and the intraoperative at a later stage. The simulated images were used to identify the venous branches in the affected segment for division and the intersegmental veins to be preserved. Four 5- to 20-mm ports were used. Segmentectomy was performed by separating the pulmonary arteries and bronchi followed by dissection along the intersegmental plane. RESULTS Fifty-one patients underwent a complete thoracoscopic segmentectomy. A mini-thoracotomy was performed in 1 case because of arterial bleeding. The success rate of segmentectomies under complete thoracoscopy was 98%. The procedure was classified into 3 categories according to the degree of surgical difficulty. Before introducing the simulation, there were 4 easy cases and 1 fairly difficult case. After introducing preoperative simulation, 7 cases were classified as fairly difficult among 12 segmentectomy cases. Furthermore, 7 cases of difficult segmentectomy were performed using intraoperative simulation. No local recurrence or metastasis and no mortality were observed during the follow-up. CONCLUSIONS Thoracoscopic pulmonary segmentectomy under 3-dimensional multidetector computed tomography simulation is a safe technique.

Experimental study of cerebral autoregulation during cardiopulmonary bypass with or without pulsatile perfusion

Twenty-four adult mongrel dogs were divided into four equal groups according to the following method of cardiopulmonary bypass: normothermic continuous (so-called nonpulsatile) perfusion, normothermic pulsatile perfusion, hypothermic continuous perfusion, and hypothermic pulsatile perfusion. Cerebral blood flow was determined by measuring the volume of sagittal sinus venous blood outflow with a transit-time ultrasonic flowmeter. Cardiopulmonary bypass was initiated at a flow rate of 80 ml/kg per minute. Cerebral temperature was maintained at 37 degrees C in the normothermic groups and at 25 degrees C in the hypothermic groups. Arterial pH and carbon dioxide were maintained within the physiologic range by alpha-stat acid-base regulation. Mean cerebral perfusion pressure and blood flow were not affected during 90 minutes of the bypass. The respective values were 67.1 mm Hg and 37.1 ml/100 gm brain per minute with normothermic continuous perfusion, 72.8 mm Hg and 39.0 ml/100 gm per minute with nonpulsatile perfusion, 98.0 mm Hg and 23.0 ml/gm per minute with hypothermic continuous perfusion, and 86.8 mm Hg and 22.3 ml/100 gm per minute with hypothermic pulsatile perfusion. Pump flow rates were altered from 10 to 120 ml/kg per minute in a stepwise fashion to obtain graded changes of perfusion pressure. Cerebral blood flow, however, was not changed significantly by cerebral perfusion pressure so long as perfusion pressure was greater than 50 mm Hg. Conversely, cerebral blood flow changed proportionally with cerebral perfusion pressure at a pressure less than 50 mm Hg. The correlation between cerebral blood flow and perfusion pressure was described as two separate lines determined by linear regression. The slope of the regression line relating cerebral blood flow to perfusion pressure was 0.16 +/- 0.08 for a cerebral perfusion pressure above 50 mm Hg and 0.68 +/- 0.11 below 50 mm Hg in the normothermic continuous perfusion group; 0.14 +/- 0.09 and 0.32 +/- 0.09 with normothermic pulsatile perfusion; 0.10 +/- 0.04 and 0.62 +/- 0.18 with hypothermic continuous perfusion; 0.09 +/- 0.08 and 0.39 +/- 0.04 in the hypothermic pulsatile perfusion group. The slope above 50 mm Hg was significantly smaller and closer to zero in all groups than it was at a perfusion pressure below 50 mm Hg (p < 0.05).(ABSTRACT TRUNCATED AT 400 WORDS)

Role of diffusion-weighted magnetic resonance imaging for predicting of tumor invasiveness for clinical stage IA non-small cell lung cancer

OBJECTIVES Recently, diffusion-weighted MR imaging (DWI) for the whole body has become available for clinical use, as has been previously used for the central nervous system. Favorable results have been reported using this imaging system to differentiate between benign and malignant lesions in some organs, and to correlate with the degree of cell differentiation in lung cancer. The purpose of this study was to assess the role of DWI for predicting tumor invasiveness of non-small cell lung cancers (NSCLC), especially for clinical stage IA patients. METHODS From January 2006 to September 2007, preoperative DWI and 18F-FDG-PET/CT were performed on 41 patients with clinical stage IA NSCLC who had undergone curative operations. Lung cancers that exhibited nodal, lymphovascular or pleural invasion were defined as invasive lung cancers. Nodules with strong dark signal, as observed by DWI in spinal cords, were defined as DWI-positive. We analyzed the associations between the pathological findings and the following preoperative clinical factors: age, gender, smoking history, preoperative CEA levels (<5.0 or >/=5.0ng/ml), preoperative tumor size, SUV max on PET/CT (<5.0 or >/=5.0) and DWI (positive or negative). RESULTS A total of 15 lesions (37%) were assessed as DWI-positive and 26 lesions (63%) were DWI-negative. Univariate analyses showed positive correlations for development of invasive cancer with the preoperative CEA level (p=0.049), SUV max (p=0.001) and DWI (p<0.001). Multivariate analysis showed that DWI (p=0.005) was an independent predictive factor for tumor invasiveness. CONCLUSION Our results suggest that DWI might be a useful method for predicting tumor invasiveness for clinical stage IA NSCLC.

Total thoracoscopic pulmonary segmentectomy

OBJECTIVE In lung resection, thoracoscopy has been mainly used for wedge resection and lobectomy. There have been very few reports on pulmonary segmentectomy, mainly because of its complex nature. The present report evaluates the safety and efficacy of thoracoscopic pulmonary segmentectomy for the treatment of benign lung diseases or small lung carcinomas. METHODS The study involved 30 patients who underwent thoracoscopic segmentectomy without a minithoracotomy from September 2004 to March 2008. The median age of the patients was 69 years (range, 16-81 years). Four 5-20 mm ports were used. The pulmonary vessels were ligated, and the bronchi were closed using a stapler. An electrocautery was used for intersegmental dissection. Chest tubes were inserted in all cases. RESULTS Twenty-eight patients underwent complete thoracoscopic segmentectomy. A minithoracotomy was created in one case because of arterial bleeding, and open lobectomy was performed in another case owing to the diagnosis of small cell carcinoma. The operative time ranged from 147 to 425 min (median time, 216 min). The inserted chest tubes were maintained in position for 1-7 days (median duration, 1 day). One patient developed subcutaneous emphysema that spontaneously resolved. No mortality was observed for 30 days after the surgery. Further, no local recurrence or metastases were observed during follow-up in cases of malignancy. CONCLUSIONS Thoracoscopic pulmonary segmentectomy is a feasible and safe technique. Reduced postoperative pain and an improved cosmetic outcome are considered advantages of this minimally invasive procedure.

Anatomical Lung Segmentectomy Simulated by Computed Tomographic Angiography

We describe the benefits of simulating lung segmentectomy by using multi-detector computed tomographic angiography. Preoperative determination of the anatomical, intersegmental plane is possible by visualizing the branches of the pulmonary veins. This new technique could be useful in thoracoscopic segmentectomy of the lung.

The role of epicardial adipose tissue in coronary artery disease in non-obese patients

BACKGROUND Epicardial adipose tissue (EAT) surrounding the heart may contribute to the development of coronary artery disease (CAD) through its local secretion of adipocytokines. Although the quantity of EAT is associated with obesity and metabolic syndrome, the role of EAT in the development of CAD in non-obese patients remains to be determined. METHODS This study included 41 patients with CAD who underwent coronary artery bypass graft surgery and 28 patients without CAD who underwent other cardiac surgery. EAT volume was measured by 64-slice multi-detector computed tomography before the surgery. We obtained pericardial fluid and epicardial and subcutaneous adipose tissue samples at the surgery. We investigated the relationship between EAT volume and adiponectin levels in pericardial fluid and incident CAD in patients with and without obesity (body mass index>25 kg/m(2)). RESULTS There was no significant difference in EAT volume between obese patients with and without CAD (55.5 ± 40.2 mL vs. 40.1 ± 19.7 mL, p=0.323). However, EAT volume was significantly greater in non-obese patients with CAD compared to those without CAD (35.0 ± 18.8 mL vs. 15.7 ± 11.0 mL, p<0.001). Adiponectin concentrations in pericardial fluid were significantly lower in non-obese patients with CAD compared to those without CAD (2.7 ± 2.0 μg/mL vs. 4.3 ± 3.7 μg/mL, p=0.049), whereas the adiponectin levels were decreased in obese patients regardless of the presence of CAD. Non-obese patients with CAD had significantly larger size adipocytes in EAT but not subcutaneous adipose tissue compared to those without CAD. Multiple logistic regression analysis showed that increased EAT volume was independently associated with incident CAD in non-obese patients. CONCLUSION Increased EAT may play a crucial role in development of CAD through impairment of adiponectin secretion in non-obese patients.

Slip knot bronchial ligation method for thoracoscopic lung segmentectomy.

We report a novel monofilament slip knot technique for bronchial ligation and for visualization of the anatomic plane during lung segmentectomy. After threading the bronchus, a slip knot is made outside the thorax. During lung ventilation, one end of the string is pulled, and the knot slips to reach the bronchus without a knot-pusher. Bronchial ligation is then performed to block the outflow of segmental air while the segment remains expanded, whereas the other segments become collapsed. This technique allows identification of the anatomic intersegmental plane, facilitating thoracoscopic anatomic lung segmentectomy.

A modified surgical approach for giant left coronary arterial aneurysm

An 80-year-old female with a persistent cough was found on volumerendered tomorgraphy (CT) to have a 6.5× 5.7-cm coronary artery aneurysm compressing the posterior portion of the pulmonary artery (PA) (Fig. 1). Two smaller “daughter aneurysms” 1.5 and 1.4 cm were located on the anterior aspect of the PA (Fig. 1). In addition, a bronchial artery aneurysmwas also noted (Fig. 1). There were no coronary artery occlusions or fistulous communications between the aneurysm and any cardiac chamber seen on a coronary angiogram. At the time of surgery, a mediansternotomy was performed and cardiopulmonary bypass (CPB) was established with ascending aortic and bicaval cannulation. A 6-cm calcifiedmass was noted superior and posterior to the heart between the ascending aorta and PA (Fig. 2). Following cardioplegic arrest with antegrade/retrograde blood cardioplegia, a feeding artery arising from the proximal right coronary artery was ligated at its origin. Inadequate exposure of the proximal left main coronary (LMC) artery and the aneurysm necessitated transection of both the ascending aorta and the main PA (Fig. 3). A feeding artery arising from the LMC artery was ligated at its origin. The aneurysmal

Port-Access Thoracoscopic Anatomical Segmentectomy for Pediatric Intralobar Pulmonary Sequestration

This report describes successful port-access thoracoscopic anatomical left lateral and posterior basal (S9 + 10) lung segmentectomy performed for intralobar pulmonary sequestration (ILPS) in a 5-year-old girl with recurrent pneumonia. Computed tomography revealed a multilocular lung abscess and an anomalous artery arising from the left gastric artery supplying the affected segment. After diagnosing ILPS, we performed thoracoscopic anatomical S9 + 10 segmentectomy. We consider thoracoscopic lung segmentectomy to be an important therapeutic option for pediatric ILPS.