Hiroyuki Kasajima

Increased in situ expression of nitric oxide synthase in human colorectal cancer

Abstract There is growing evidence that nitric oxide (NO) has an important role in tumor growth. However, information on the expression of NO synthase (NOS) in colorectal cancers is scanty. We therefore investigated the distribution and expression of NOS in human colorectal cancers. The expression of three types of NOS, inducible (iNOS), endothelial (eNOS) and neuronal (nNOS), was examined by immunohistochemistry in 25 cases of colorectal cancer. The expression of iNOS was also investigated at the mRNA level using the reverse transcriptase polymerase chain reaction (RT-PCR) in 6 cases. Correlations were made between iNOS expression and the histopathological findings. Immunoreactive iNOS was detected in the tumor cells in 22 cases (88%) with diffuse cytoplasmic reactions. Expression of iNOS-mRNA detected by RT-PCR in three tumor tissues was over five-fold that in normal mucosa. Intensified immunoreactivity of iNOS was associated with vascular invasion. iNOS expression did not correlate with pathological staging, tumor size, lymph node metastasis, p53 expression or tumor vessel density. Immunoreactive eNOS stained more strongly in the endothelial cells of microvessels within and around the tumor than in the areas remote from the tumor. There is enhanced expression of iNOS and eNOS in human colorectal cancers, which may correlate with tumor growth and vascular invasion.

Enhanced in situ expression of aldose reductase in peripheral nerve and renal glomeruli in diabetic patients

Abstract.To explore the relationships between polyol pathway-related enzymes and pathologic features, we examined the immunohistochemical expression of aldose reductase (AR) and sorbitol dehydrogenase (SDH) in the peripheral nerve and kidney tissues collected postmortem from diabetic patients and compared it with those from non-diabetic patients. Tissue AR protein concentrations were also quantified. In non-diabetic patients, AR distributed in pericytes, smooth muscle cells of endo- and epi-neurial microvessels, Schwann cells in the sciatic nerve, and tubular cells of the renal medulla. By contrast, positive SDH reactions were observed in tubular cells of the renal cortex but were faint in the sciatic nerve. Diabetic patients frequently showed dense AR expressions in the sciatic nerve. In nephropathic diabetic patients, the glomerular mesangial area showed diffuse positive reactions for AR. The severity of structural changes in glomeruli correlated with the intensity of immunoreactive AR (r2=0.626, P<0.01). AR contents in the renal cortex and sciatic nerve from diabetic patients were 1.5- and 1.8-fold greater than those from non-diabetic patients, respectively (P<0.05 for both). These findings are the first to demonstrate enhanced AR expressions in peripheral nerve and renal glomeruli in diabetic patients and its relevance to the characteristic pathology.

Video-assisted thoracoscopic transdiaphragmatic liver resection for malignant tumors located in the posterosuperior segments.

469 Background: Laparoscopic liver resection has recently become more common. However, it is difficult to resect laparoscopically the liver tumor located in the posterosuperior segments (IVa, VII and VIII), especillay for patients with liver cirrhosis. Compared to laparoscopy, gaining access to tumors in the dome of the liver may be more easily obtained via thoracoscopy.Therefore, we describe the technique and outcome of a video-assisted thoracoscopic transdiaphragmatic liver resection in patients with a malignant tumor of the liver. Methods: Five female patients underwent video-assisted thoracoscopic transdiaphragmatic partial hepatectomy. The tumors were located at segment VIII in 4 patients and segment VII in 1. Three patients were preoparatively diagnosed with hepatocellular carcinoma, and two were metastatic tumor of the colorectal cancer. Underlying cirrhosis was staged as Child-Pugh B in 2 cases and Child-Pugh A in 1. Thoracoscopic transdiaphragmatic partial hepatic resection was chosen due to the ...