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Biomedical subjects

A Saiura

Publications and source records attributed to A Saiura.

14 recordsLinked to original sources

Tranilast inhibits transplant-associated coronary arteriosclerosis in a murine model of cardiac transplantation.

Accelerated coronary arteriosclerosis remains a major problem for the long-term survival of cardiac transplant recipients. However, the pathogenesis of graft vasculopathy is poorly understood and there is no effective therapy. Tranilast is a promising drug that may prevent post-angioplasty restenosis. Here, we investigated whether orally administered tranilast inhibits the development of intima hyperplasia in a mouse model of cardiac transplantation. Cardiac allografts from BALB/c mice were transplanted heterotopically into C3H/He mice. Mice were administered either vehicle or tranilast everyday by gavage. Morphometrical analysis of the cardiac allografts harvested at 2 months revealed that the administration of tranilast significantly reduced the development of coronary atherosclerosis. In the mice treated with tranilast, up-regulation of the cyclin-dependent kinase inhibitor p21 was observed in the allografts, accompanied by a reduced number of proliferating cells. Tranilast also suppressed transforming growth factor-beta (TGF-beta) expression. Tranilast may be effective in preventing transplant-associated arteriosclerosis through its anti-inflammatory and anti-proliferative effects.

Animals↗

A comparison of gene expression in murine cardiac allografts and isografts by means DNA microarray analysis.

BACKGROUND: Acute rejection of allografts remains a significant problem in clinical transplantation, and the fundamental mechanism underlying this rejection are as yet only poorly elucidated. Recently, DNA microarrays have come into use for the study of gene expression profiles, and we have taken advantage of this new technology to investigate acute rejection. We compared mRNA profiles in murine cardiac allografts with isografts using DNA microarrays with probe sets corresponding to more than 11,000 mice genes. METHODS: We screened for gene expression changes in murine cardiac allografts between fully incompatible mice strains (BALB/c H2d to C3H/He H2k) using a DNA microarray. The heart was heterotopically transplanted. Allografts (BALB/c to C3H/He) were removed on days 1, 3, and 5. As a control, isografts (C3H/He to C3H/He) harvested on days 1, 3, and 5 and native hearts of both strain mice (C3H/He and BALB/c) were obtained. RESULTS: On day 5, interferon-gamma (IFN-gamma) and many IFN-gamma-inducible genes were profoundly induced in the allograft relative to isograft. Monokine induced by IFN-gamma was most profoundly induced followed by inducibly expressed GTPase and Lmp-2. IFN-gamma was also profoundly induced. The induction was detectable from day 3. In contrast, genes regulated by other cytokines exhibited only modest changes. CONCLUSION: IFN-gamma-inducible genes are specifically up-regulated in murine cardiac allografts, suggesting that signaling mediated by IFN-gamma may play an important role in the late phase of acute rejection in vivo.

Animals↗

A mouse model of vascular injury that induces rapid onset of medial cell apoptosis followed by reproducible neointimal hyperplasia.

Genetically modified mice serve as a powerful tool to determine the role of specific molecules in a wide variety of biological phenomena including vascular remodeling. Several models of arterial injury have been proposed to analyze transgenic/knock-out mice, but many questions have been raised about their reproducibility and physiological significance. Here, we report a new mouse model of vascular injury that resembles balloon-angioplasty. A straight spring wire was inserted into the femoral artery via arterioctomy in a small muscular branch. The wire was left in place for one minute to denude and dilate the artery. After the wire was removed, the muscular branch was tied off and the blood flow of the femoral artery was restored. The lumen was enlarged with rapid onset of medial cell apoptosis. While the circumference of the external elastic lamina remained enlarged, the lumen was gradually narrowed by neointimal hyperplasia composed of smooth muscle cells. At 4 weeks, a concentric and homogeneous neointimal lesion was formed reproducibly in the region where the wire had been inserted. Similar exuberant hyperplasia could be induced in all strains examined (C57BL/6J, C3H/HeJ, BALB/c, and 129/SVj). This model may be widely used to study the molecular mechanism of post-angioplasty restenosis at the genetic level.

Angioplasty, Balloon↗

The gene expression profile of human umbilical vein endothelial cells stimulated by tumor necrosis factor alpha using DNA microarray analysis.

Stimulation of vascular endothelial cells by tumor necrosis factor alpha (TNFalpha) plays a critical role in the pathogenesis of inflammation and vascular diseases. Changes in the gene expression profile in cultured human umbilical vein endothelial cells (HUVEC) treated with TNFalpha was analyzed with high-density oligonucleotide arrays comprised of 35,000 genes. TNFalpha stimulation profoundly induced genes involved in signal transduction, leukocyte adhesion and chemoattraction. ICAM-1 mRNA (fold change 111.9) was most profoundly induced followed by TNFalpha receptor-associated factor 1 (TRAF1) (95.5), Bcl3 (71.8), IL8 (65.4), fractalkaine (62.4), E-selectin (48.0), lymphotoxin beta (41.3) and VCAM-1 (31.7). In addition to these previously known genes, 18 poorly characterized or novel genes known as ESTs profoundly induced by TNFalpha. Initial sequencing analysis identified three of these the genes for squalene epoxydase, chromodomain helicase DNA binding protein 4, and CLP respectively. Further analysis of these genes will provide important information about TNFalpha signaling and function in vascular endothelial cells.

Cell Line↗

[Two patients with liver metastasis from gastric cancer who responded remarkably to combined therapy of 5'-DFUR and PSK].

Two patients with liver metastasis from gastric cancer who responded remarkably to a combined therapy of 5'-DFUR and PSK are reported. The first patient had liver metastases 8 months postoperatively. Her AFP level was 513 ng/ml and CEA was 30 ng/ml. After the combined therapy, all liver metastases showed a calcified change. Tumor markers of AFP and CEA decreased remarkably to the normal level within 3 weeks after the therapy. The patient had no relapse as of December 1999. The second patient with liver metastases was treated using the same combined therapy for 14 days preoperatively. The size of liver metastases had decreased remarkably by the time of the operation. A small metastasis of S8 (0.5 x 0.5 cm) was resected. No other liver metastasis was detected by intraoperative ultrasonography. The patient had no relapse as of February 2000. It is reported that PSK produces several cytokines which induce thymidine phosphorylase expression. The present report suggests that the upregulation of PyNPase might enhance the antitumor effect of 5'-DFUR.

Aged↗

Metachronous bile duct cancer in a patient surviving for a decade and undergoing curative surgery twice.

We report a 75-year-old woman with metachronous bile duct cancer who underwent curative resection twice and has survived for a decade. In 1989, she was admitted because her serum alkaline phosphatase level was elevated. Computed tomography (CT) showed a low-density mass, 2 cm in diameter, at the left hepatic duct and intrahepatic bile duct dilatation in the left lobe. We diagnosed the lesion as an intrahepatic bile duct cancer and performed extended left hepatic lobectomy with systematic lymph node dissection. The histological diagnosis was a well differentiated cholangiocellular carcinoma with hepatic hilar and celiac lymph node metastases (T1N2M0, Stage IVB). In 1996, she was re-admitted with obstructive jaundice. CT showed a slightly enhanced mass, 4 cm in diameter, in the pancreatic head. After reducing the jaundice by percutaneous transhepatic biliary drainage, pancreatoduodenectomy was performed. The histological diagnosis of this lesion was a moderately differentiated adenocarcinoma originating from the intrapancreatic bile duct. Ten years after the first operation, she is leading a normal daily life with no cancer recurrence. These findings suggest that repeated curative surgery can result in a long-term survival of patients with metachronous bile duct cancer.

Adenocarcinoma↗

Successful surgical resection of solid cystic tumor of the pancreas with multiple liver metastases and a tumor thrombus in the portal vein.

We report a case of solid cystic tumor of the pancreas with widespread liver metastases and a tumor thrombus in the portal vein. The patient was a 43-year-old woman. She was referred because of an upper abdominal mass and weight loss. Computed tomography disclosed a 10-cm cystic and calcified mass in the body and tail of the pancreas and multiple masses in the liver. She underwent a distal pancreatectomy with splenectomy, extended right lobectomy, and partial resection of the liver. All the tumors were completely resected despite the presence of 20 liver metastases. Histopathological studies showed a tumor thrombus in the intrahepatic portal vein. The patient is well without any signs of recurrence 8 months after the operation. Aggressive surgical resection is considered to yield a good outcome for solid cystic tumor with liver metastases and tumor thrombus of the portal vein.

Adult↗

Benign biliary stricture associated with atherosclerosis.

We report a case of benign bile duct stricture that could not be differentiated from intrahepatic bile duct carcinoma preoperatively. The patient was a 79-year-old man. Computed tomography showed dilatation of the intrahepatic bile duct in the left lobe. Direct cholangiography showed segmental stricture of the left bile duct. Angiography showed narrowing of the left hepatic artery. Although bile cytology did not show malignant cells, we suspected intrahepatic bile duct carcinoma preoperatively. We performed extended left hepatic lobectomy. Histopathologic examination of the resected duct also showed no malignant cells; fibrosis with infiltration by lymphocytes was seen at the bile duct stricture. In addition, the resected liver specimen showed sclerotic change in the intrahepatic arteries. The postoperative course was uneventful for more than 26 months, without recurrence or cholangitis. We encountered a very rare case of benign segmental bile duct stricture, which was difficult to differentiate from bile duct carcinoma. We think the biliary stricture was secondary to atherosclerosis which may have caused bile duct ischemia.

Aged↗