Search PubMed⌕ Search

Biomedical subjects

N Kawano

Publications and source records attributed to N Kawano.

At least 91 records · Page 5Linked to original sources
PubMed1991

Meningiomas differentiating to arachnoid trabecular cells: a proposal for histological subtype "arachnoid trabecular cell meningioma".

Three cases of meningiomas which had abundant small vacuoles in the tumor tissue are reported. By electron microscopy, the tumor cells exhibited long and thin processes, the tips of which were united by desmosomes. The tumor tissue was revealed to have wide extracellular spaces which corresponded to the vacuoles observed by light microscopy. In previous literature, various terms have been used when referring to this meningioma, such as microcystic meningioma or vacuolated meningioma. Since the ultrastructure of the tumor showed similarity to that of normal arachnoid trabecular cells, we propose to call the tumor "arachnoid trabecular cell meningioma" denoting its morphological nature clearly.

Cell Differentiation↗
PubMed1991

Malignant hemangiopericytoma of the liver: report of a case.

A 30 year old female was admitted with right upper abdominal pain and fever. Ultrasonography and computed tomography revealed a large cystic mass in the right lobe of the liver, and aspiration bacteriology was negative. A right hepatic lobectomy was performed for a suspected cystadenocarcinoma, however, the tumor was histologically diagnosed as a hemangiopericytoma with prominent venous invasion. The patient died within a short time of multiple pulmonary metastases. Primary hepatic hemangiopericytoma is extremely rare, and according to our research, this is only the 4th case reported in the literature.

Adult↗
PubMed1991

Surgical experience with nonparasitic cysts of the liver--the characteristics and constituents of cyst fluid.

Fifteen patients with nonparasitic hepatic cysts underwent surgery to relieve abdominal complaints, at the First Surgical Department, Tokyo University Hospital between 1966 and 1989. Total removal of the cyst was carried out in 14 of the patients, while puncture and aspiration only were performed in the other patient in whom a cyst had ruptured spontaneously, after which hemoperitoneum was observed at emergency laparotomy. The size of the cysts varied from 7-19 cm with a mean of 12.4 cm. Histological study revealed a congenital cyst in 14 patients and a cystadenoma in one. The epithelium lining of the internal surface of the congenital cysts was highly atrophic and desolated and often disappeared. Examination of the cyst fluid revealed the same concentration of electrolytes as in the serum. Hepatic enzyme levels were usually lower than in the serum, but lactic dehydrogenase and aminotransferase levels were elevated in a few cases. Tumor marker levels of the cyst fluid were higher than those in the serum in four of five patients examined.

Adult↗
PubMed1991

Comparison of bovine, sheep and goat milk lactoferrins in their electrophoretic behavior, conformation, immunochemical properties and lectin reactivity.

1. The biochemical properties of bovine, goat and sheep lactoferrin were compared. Molecular weights of the three lactoferrins were estimated to be 78,000 to 80,000 as determined by SDS-PAGE. By IEF, microheterogeneity was observed for all of them. 2. Partial antigenic identity was observed between bovine lactoferrin and goat or sheep lactoferrin by immunodiffusion method. 3. CD spectra at the u.v. region of the three lactoferrins suggested their similar secondary and tertiary structural profiles. 4. Reactivities with peroxidase-conjugated lectins showed that the carbohydrate compositions of the three ruminants' lactoferrin were the same but not identical with that of human lactoferrin.

Animals↗
PubMed1990

Postoperative recurrence of hepatocellular carcinoma.

Sixty-nine patients with hepatocellular carcinoma underwent curative hepatic resections as primary cases from 1981 to 1986. Seven patients died in the hospital after operation. The other 62 patients left the hospital and were closely followed for 25 to 78 months. Recurrence of carcinoma became obvious in 41 (66%) of 62 patients. The clinical and pathologic features of these 41 patients were not significantly different from those of the other patients. Recurrent tumors were found in the residual liver in 38 patients (93%), in the bone in 2 (5%), and in the lung in 1 (2%). Recurrence was diagnosed within 1 year, between 1 and 2 years, and more than 2 years after the operation in 22 (56%), 10 (26%), and 7 (18%) patients, respectively. It was difficult to determine the exact time of recurrence in two patients. There was a significant negative correlation between the size of primary tumor and time until recurrence; the larger the primary tumor, the shorter the time until recurrence. Among the 29 patients who underwent local excisions for their primary tumors, 19 recurrences were observed. Eighteen were found in the residual liver, in the same segment as the primary tumor, or in one near it. Larger hepatic resection for primary tumors is thus advocated to prevent recurrence.

Adult↗
PubMed1990

[Results of prophylactic intra-arterial infusion chemotherapy after hepatic resection in colorectal metastases].

Fourteen colorectal cancer patients with metastatic liver metastases who received prophylactic intra-arterial infusion chemotherapy (IAIC) after curative resection for liver metastases at the National Cancer Center Hospital from May 1987 to December 1989 were reviewed. 5-fluorouracil (5-FU) (15 mg/kg) and mitomycin C (MMC) (0.1 mg/kg) were infused through implantable ports weekly or every two weeks. Five patients (35.7%) developed recurrent tumors in the residual liver during 3-12 months after hepatic resection. The se five patients had more than two metastatic lesions in the liver at hepatectomy. Four patients with solitary metastatic tumor had no recurrent liver diseases. The most serious complication was sclerosing cholangitis which occurred in two patients (14%) in this series. Both cases needed drainage PTCD, but one of them died from gastro-intestinal bleeding due to hepatic failure and the other from pneumonia. These two cases showed no recurrent liver cancers.

Administration, Oral↗
PubMed1989

Long-term prognosis of surgical patients with hepatocellular carcinoma.

We reviewed 139 resected patients with hepatocellular carcinoma at our clinic between 1963 and 1987, and using the 118 cases for the period between 1963 and 1986, we analyzed the prognostic factors that influenced the long-term prognosis by comparing the survival curves. Significant differences in the survival patterns were noted when analysed on the basis of the preoperative indocyanine green maximal removal rate (greater than 0.4 mg kg-1 min-1 versus less than 0.4 mg kg-1 min-1), tumor size (greater than 5 cm versus less than 5 cm, etc.) and the existence of tumor capsule. The recurrence of carcinoma was the main cause of death of 32 patients (56%), who died after being discharged from hospital. To improve the prognosis of patients with surgically treated hepatocellular carcinoma, postoperative multidisciplinary treatment is mandatory.

Carcinoma, Hepatocellular↗
PubMed1989

Clear cell ependymoma. A histological variant with diagnostic implications.

Four cystic brain tumours, one from the frontal lobe, one in the third ventricle and two in the cerebellum, were studied histologically including immunostaining and electron microscopy. Anatomically, all the tumours were located within or adjacent to the ventricular system. By light microscopy, the tumours had a largely honeycomb pattern and were made up of clear cells. Some of the clear cells showed positive for GFAP. Leu 7, Factor VIII and NSE were negative. Electron microscopy of the areas with clear cells revealed densely packed polyhedral cells with clear cytoplasm. They had well developed intercellular junctions, microvilli and some cilia which confirmed their ependymal derivation. Perivascular pseudorosettes or papillary features were only seen in limited areas, where GFAP was strongly positive in the tumour cell processes. As these tumours mimic oligodendroglioma and cerebellar haemangioblastoma, they are called as "clear cell ependymoma" to obviate such errors in diagnosis.

Adult↗
PubMed1989

The beneficial effect of superoxide dismutase on the rat liver graft.

We performed orthotopic liver transplantation in male Wistar rats and investigated the effect of superoxide dismutase (SOD) on the liver graft. Animals were divided into the four following experimental groups. Group I was an untreated control group, group II received oxygen, group III received SOD and group IV received both oxygen and SOD. The dose of SOD was 3 mg/kg which was injected intravenously into both donors and recipients during the operation. Oxygen was given through an oxygen inhaler to both donors and recipients during the operation. The preservation time of the liver graft ranged from 4 hours and 41 minutes to 5 hours and 40 minutes. The survival after liver transplantation was compared among groups I, II, III and IV. Group IV showed a significantly higher survival rate than groups I and II by two weeks after liver grafting, but there was no statistical difference in the survival rates between groups III and IV. These results indicate the beneficial effect of SOD on the rat liver graft and may implicate oxygen free radicals in the pathogenesis of ischemia/reperfusion injury in liver grafts.

Animals↗
PubMed1989

A newly designed flow-regulating device in shunt therapy of hydrocephalus.

A new flow-regulating device for shunting in hydrocephalus was designed to limit an excess flow by a pressure-head between the cerebral ventricle and the abdominal cavity in a standing position. The device has two diaphragm valves connected to each other by two lines: one is a shunting line to transfer cerebrospinal fluid and the other is a control line filled with a control fluid with a higher density than cerebrospinal fluid. The performance of the model device with a natural rubber sheet diaphragm was tested in a mock system, using glycerol for the control fluid and water for the transfer fluid in vitro. Results show that device decreases the excess flow when the pressure-head between two valves exceeds 35 cm.

Cerebrospinal Fluid Shunts↗
PubMed1989

Cranial burr hole for revascularization in moyamoya disease.

Currently, superficial temporal artery-middle cerebral artery (MCA) anastomosis, encephalomyosynangiosis (EMS), and encephalo-duro-arterio-synangiosis are used to treat moyamoya disease and are reported to effectively improve ischemic symptoms. All are methods of reversing the flow of blood from the external carotid artery system into the cortical branches of the MCA. As moyamoya disease advances, these operations alone will predictably not correct the deterioration in blood flow in the territory of the anterior cerebral artery. It was noted in a case of moyamoya disease with intraventricular hemorrhage that a burr hole, made in the frontal region for drainage purposes, induced marked neovascularization. Since then, similar frontal burr holes have been made in five juvenile cases of moyamoya disease; this procedure involved making a burr hole in both frontal bones and incising both the dura and the arachnoid membrane. In two cases a frontal burr hole in both frontal bones and incising both the dura and the arachnoid membrane. In two cases a frontal burr hole was placed simultaneously with EMS, and in the others the frontal burr hole was made following EMS. The clinical symptoms improved after the frontal burr hole was made, and dynamic computerized tomography revealed improved circulation in the frontal regions. Together with conventional surgical therapy for juvenile cases of moyamoya disease, this operation is considered beneficial both to the circulation in the frontal region and for the protection of frontal brain function.

Arterial Occlusive Diseases↗
PubMed1989

[Blunt injury of the vertebral artery: report of three cases].

The authors reported three cases, whose vertebral arteries had been injured by blunt trauma to the neck which was followed by cerebello-brainstem infarctions. Case 1: a 32-year-old man, who developed severe vertigo and nausea 7 days after a traffic accident. He showed neck pain and horizontal nystagmus on admission. Three days later, he became drowsy. CT scan of the head demonstrated right-side cerebellar infarction, and the angiography revealed an occlusion of the right vertebral artery at C4-5 level. After the removal of the right cerebellar hemisphere, he recovered neurologically and was discharged from the hospital, able to walk. Case 2: a 47-year-old man, who suddenly became comatose 6 hours after an accident. Plain CT demonstrated a highly dense basilar artery. Angiography revealed the occlusion of the left vertebral artery, and severe stenosis of the right vertebral artery. The basilar artery was not visualized. Anticoagulant therapy was started immediately. He survived, but he developed locked-in syndrome. Case 3: a 53-year-old man, who developed transient apnea after an injury. On admission, neurological examination showed horizontal nystagmus, weakness of his right upper limb, and sensory disturbance in the left side of the body. Neck traction was done for spinal C1 and C2 fractures. Twenty-one hours after the injury, he became comatose suddenly. The four-vessels angiography revealed the occlusion of both vertebral arteries. The basilar artery was visualized through the posterior communicating arteries. He died on the 6th day after the trauma.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

The effect of nifedipine, a calcium channel blocker, on liver ischemia in dogs.

This study was undertaken in order to determine whether the administration of nifedipine, a calcium channel blocker, could protect the liver from ischemic damage and to investigate its effect on the hepatic cellular energy status and cardio-vascular system after 60 minutes of hepatic ischemia in dogs. The ischemia was induced by temporarily clamping the portal vein and hepatic artery. One group of animals (n = 17) received nifedipine (5 micrograms/kg body weight) intravenously 15 minutes before the induction of liver ischemia, which was continued at a dose of 0.2 microgram/kg body weight/min throughout the ischemic period, and for an additional 30 minutes afterwards. Control dogs (n = 16) were not given nifedipine and survival was observed over seven days. The survival rate was 83 per cent in the nifedipine treated animals and 0 per cent in the control animals. Serum glutamic oxaloacetic transaminase levels were greatly increased following ischemia, and they were significantly lowered with the nifedipine treatment. The hepatic energy charge decreased remarkably during the hepatic ischemia, however it increased gradually after declamping but did not returned to its preoperative value in either group until one hour later and then it was higher in the nifedipine treated animals than in the control animals. Cardiac index and portal venous blood flow ratio remained higher in the nifedipine treated animals than in the control animals, after the ischemic period. These results suggest that nifedipine may have a powerful cytoprotective effect and that the period of warm hepatic ischemia could be prolonged with its use.

Alanine Transaminase↗
PubMed1988

Calcium pyrophosphate dihydrate crystal deposition disease in the cervical ligamentum flavum.

The authors describe three cases of cervical radiculomyelopathy caused by calcium pyrophosphate dihydrate crystal deposition disease (CPPDcdd). Radiological investigations revealed nodular calcifications, 5 to 7 mm in diameter, in the cervical ligamentum flavum compressing the spinal cord. Light microscopic, scanning electron microscopic, and x-ray diffraction studies were performed on all three surgical specimens obtained by laminectomy. In two of the cases x-ray microanalysis and transmission electron microscope studies were also performed. This study defined the presence of two patterns of crystal deposition in the ligamentum flavum. One is a nodular deposit, in which hydroxyapatite crystals are seen in the central part of the nodules, with calcium pyrophosphate dihydrate (CPPD) being distributed thinly around them. The other pattern is a linear deposit seen in multiple ligaments and composed of pure CPPD, which causes minimal thickening of the ligaments. A transitional pattern between the two types was also observed. This study revealed details of the nodular deposition of crystals in the ligamentum flavum and demonstrates that CPPDcdd and so-called "calcification of the ligamentum flavum" are the same disease: namely, CPPDcdd. Hydroxyapatite is assumed to have been transformed from CPPD.

Aged↗
PubMed1988

A new instrument for hepatic resection.

A new instrument for hepatic resection was designed and developed. Use of the hepatic comb during hepatic resection is described. It is very simple in shape, easy to handle and inexpensive. Using the instrument has made mandatory rapid hepatectomy in poor risk patients possible. The hemostatic effect of the procedure with this instrument is excellent, which is an important consideration in surgical treatment of the liver.

Hepatectomy↗
PubMed1988

[Origin of the capsule of a chronic subdural hematoma--an electron microscopy study].

To understand the early stage of subdural neomembrane (SN) formation, we examined 23 outer SNs and two inner SNs of chronic subdural hematomas in surgical specimens. Ultrastructurally, the cellular component of the outer SN was fibroblasts, myofibroblasts, smooth-muscle cells (in four cases), blood vessels and blood-born cells. Dural border cells were observed only in limited areas. Namely, the outer SN is a simple granulation tissue which originates from multiple sources of mesenchymal cells in dura mater, and dural border cells are only one of constituent sources for SN formation. The inner SN was simply composed of slender spindle cells which were mostly fibroblasts and some were recognized as dural border cells. Our results showed that the subdural hematoma is actually an "intra" dural hematoma which is formed within the split dural border cell layer. The dura mater with rich vascular supply forms thick granulation tissue, that is outer SN and a few dural border cells on the underlying arachnoid membrane form thin fibrous inner SN.

Adolescent↗