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Biomedical subjects

K Takasaki

Publications and source records attributed to K Takasaki.

At least 73 records · Page 4Linked to original sources
PubMed1998

Analysis of postoperative liver function of donors in living-related liver transplantation: comparison of the type of donor hepatectomy.

BACKGROUND: There is a potentially significant risk to the donor in living-related liver transplantation. METHODS: We analyzed surgical risk and stress to 35 donors in living-related liver transplantation with special reference to the types of donor hepatectomy. Donor surgery was performed in one of three ways: (1) lateral segmentectomy without ligation of the middle hepatic vein (MHV) in the remnant liver (group 1, n=21); (2) lateral segmentectomy with ligation of MHV in the remnant liver (group 2, n=6); and (3) left lobectomy with MHV (group 3, n=8). RESULTS: No critical complications were observed in any group. The postoperative enzyme levels in group 2 were significantly higher than those in groups 1 and 3 (P<0.01). Although blood loss was covered by autologous blood transfusion in the first six cases, no banked blood was transfused in any of the cases. Surgical duration was significantly longer and blood loss was significantly greater in group 3 than in group 1 (P<0.05). Follow-up computed tomography showed atrophic changes in segment IV in groups 1 and 2. No remarkable changes were seen in segments V or VIII in any of the three groups. CONCLUSION: Regardless of the donor hepatectomy procedure, serious complications did nor occur after surgery. Although it should be noted that the type of donor hepatectomy affects postoperative donor liver function, left lateral segmentectomy with ligation of MHV in the remnant liver is a useful method for obtaining liver grafts from living-related donors who have unusual anatomic variations of the hepatic veins.

Adult↗
PubMed1998

Minute nodular intrahepatic cholangiocarcinoma.

BACKGROUND: This study describes the clinicopathologic features of minute intrahepatic cholangiocarcinoma (ICC) and clarifies the relation between minute nodular ICC and hepatitis viral infection. METHODS: The presence of hepatitis C virus antibody (anti-HCV) and hepatitis B surface antigen (HBsAg) was examined in the serum of 50 patients with ICC who underwent hepatectomy from 1990-1996. The ICCs included 12 minute tumors (<3 cm in greatest dimension), 6 of which were nodular type and 6 others were nonnodular type (5 of periductal spreading or infiltrating type and 1 of intraductal type). RESULTS: Of these 50 patients with ICC, 16 (32%) were positive for anti-HCV, 5 (10%) were positive for HBsAg, and 1 (2%) was positive for both. The prevalence of hepatitis viral infection in cases of minute nodular-type tumor (83%; 5 patients positive for anti-HCV) was significantly higher than that in cases of minute nonnodular-type tumor (0%; P < 0.05). These minute nodular-type tumors were detected during follow-up of patients with chronic hepatitis or cirrhosis. All patients were treated with hepatectomy alone. At last follow-up, 3 patients had been free of disease for >5 years after surgery. However, 1 patient died 2 years after surgery because of remnant liver and lymph node recurrence. CONCLUSIONS: Minute nodular ICC appears to be related to hepatitis viral infection and could be detected at an early stage, similar to hepatocellular carcinoma, by following up cases of chronic hepatitis or cirrhosis.

Adult↗
PubMed1998

Does gross appearance indicate prognosis in intrahepatic cholangiocarcinoma?

BACKGROUND AND OBJECTIVES: Survival after surgery for intrahepatic cholangiocarcinoma (ICC) is usually poor. The objective of this study was to investigate whether the gross appearance of ICC indicates postoperative prognosis. METHODS: Seventy patients with ICC underwent hepatectomy, with a 50% curative resection rate. Tumors were classified according to gross appearance [mass-forming (n=28), periductal-infiltrating (n=14), intraductal growth (n=10), and mass-forming plus periductal-infiltrating (n=18)], and the presence of lymph node or intrahepatic metastasis was studied microscopically. RESULTS: The incidence of positive lymph nodes was significantly higher in the patients with mass-forming plus periductal-infiltrating tumors than in those with intraductal growth tumors (P=0.0089). The curative resection rate was significantly lower in patients with mass-forming plus periductal-infiltrating tumors than in those with either mass-forming or intraductal growth tumors (P=0.0001, P=0.0048, respectively). The 5-year survival rate after surgery in patients with mass-forming plus peri-ductal-infiltrating tumors (0%) was significantly lower than that in patients with mass-forming tumors (39%) or intraductal growth tumors (69%) (P=0.0036, P=0.0011, respectively). Multivariate analysis using Cox's hazards model revealed that lymph node metastasis (P=0.0109) and curative resection (P=0.0315) were statistically significant independent prognostic factors; however, macroscopic types were not. CONCLUSIONS: Patients with mass-forming plus periductal-infiltrating ICCs have a poor prognosis; however, the macroscopic types may not be a statistically significant independent prognostic factor.

Adult↗
PubMed1998

Glissonean pedicle transection method for hepatic resection: a new concept of liver segmentation.

A new concept of hepatic segmentation along with the Glissonean pedicle tree, and the basis of hepatic resection by the Glissonean pedicle transection method are presented. The portal triad continues from the hepato-duodenal ligament to the intra-hepatic portion as the Glissonean pedicle. That is, the artery, portal vein and bile duct, together with connective tissue, are sheathed by the peritoneum to form a fibroid bundle. The entire length of the primary branches of the Glissonean pedicle and the origin of the secondary branches are located outside the liver and the trunks of the secondary and more peripheral branches run inside the liver. The ramification pattern of the tertiary branches which branch out from each secondary branch is different from patient to patient. The liver is nourished by the secondary branches of the Glissonean pedicle. Each secondary branch feeds one segment. The liver can thus be separated into three segments and an additional caudate area. The area fed by each one of the tertiary branches is cone-shaped; fermed a "cone unit". Each segment conists of six to eight cone units. In limited resections, the number of cone units to be respected is adjusted and the tertiary branches which feed these areas must be transected selectively through a hilar or a parenchymal approach. To date we have experienced no complications with this procedure, employed for 832 patients with hepatocellular carcinoma.

Carcinoma, Hepatocellular↗
PubMed1998

Genotype-phenotype correlation of patients with multiple endocrine neoplasia type 2 in Japan.

BACKGROUND: Multiple endocrine neoplasia type 2 (MEN 2) is a hereditary syndrome characterized by medullary thyroid carcinoma (MTC), pheochromocytoma and hyperparathyroidism. MEN 2 is caused predominantly by germ-line mutations of the RET proto-oncogene. This study aimed to clarify the genotype-phenotype correlation in MEN 2 patients in Japan in order to modify the clinical management according to the genotype. METHODS: Constitutive DNA of 64 MEN 2 patients (48 kindreds) were searched for mutations at exons 10, 11, 13, 14 and 16 of the RET proto-oncogene using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), direct sequencing and restriction enzyme digestion. The clinical characteristics of the patients were obtained from a previous nationwide questionnaire survey. RESULTS: Overall, 62 (96.9%) out of 64 patients had a germ-line point mutation at the hot spots. MTC and pheochromocytoma occurred equally in every genotype except C630S. Specific genotype had a correlation between tumor size and age at the operation for MTC or extent of MTC, i.e. C618S developed late onset type of MTC as compared with that of C634R, C634Y and M918T. Small MTC in C634R may be less aggressive than those in C634Y and M918T. CONCLUSIONS: DNA testing has good clinical implications for the management of patients with MEN 2 and the timing and operative procedures of thyroidectomy can be modified according to the genotype.

Adrenal Gland Neoplasms↗
PubMed1998

[Increased incidence of senile dementia in the Hansen's disease sanatoriums of Japan].

In 1973, Narita reported that the rate of demented patients above 65 years was about 2% at the sanatorium--Tama Zenshoen, which was much lower than that of the average aged people (4-5%). The reason for that was thought to be due to the acquirement of strong mind under loneliness and difficulties faced by the patients through social enforcement to live in isolation. From that report on the low percentage of dementia among the Japanese Hansen patients reemed to be widely accepted. Fifteen years later in 1988, Narita reported that the rate of demented patients above 65 years was 3.2% in males and 3.6% in females indicating still a low rate at Tama Zenshoen. In 1994, however, Narita found unexpectedly that the percentage of dementia among patients above 80 at Tama Zenshoen was higher than the average aged population. Therefore in this report, we tried to analyze the reason for this difference. In addition to Tama Zenshoen patients, we also investigated those of another Hansen disease sanatorium namely Nagashima Aiseien which has similar structural organization as Tama Zenshoen. A comparison of dementia between these two was carried out, taking patients above 65 years as the study group (Used GBS scale based on Karasawa's method). In Tama Zenshoen, the rate of patients with dementia was 18.6% in males and 31% in females. Above 80 years those were 54.4% in males and 75.9% in females. The reason for the above high rate of dementia may be probably due to the passage of long years (40 to 50 years) after the enforcement to live in isolation causing the weakening of the spirit. The patients might have got some mental support if they had offspring, but they had no way to have any under the forced contraception. On the contrary, in Nagashima Aiseisen, the percentage of patients with dementia was low, namely 3.6% in males and 9.1% in females. In those patients above 80 years, it was 2.7% in males and 6.8% in females, those were almost similar to the average normal population (6%). Such a big difference was quite surprising. The reason behind this difference, may be due to the construction of the houses for the disabled persons. Both Nagashima Aiseien and Tama Zenshoen, have small individual rooms. In Tama Zenshoen, patients are able to visit their close neighbor, only after changing their shoes or with the aid of wheel chairs, but in Nagashima Aiseien, the corridors connecting quarters allow the patients to move easily to his neighbors with bare feet or even with crawl. Therefore, in Nagashima Aiseien, the number of patients who have social contacts with their neighbors is much greater in number which make them mentally active, thus eliminating the major factors affecting dementia. We can conclude that such communication between friends and co-mates make them alert and keep the spirit in the aged.

Aged↗
PubMed1998

CYFRA 21-1 as a tumor marker for squamous cell carcinoma of the esophagus.

This study assessed the clinical value of CYFRA 21-1 in comparison with squamous cell carcinoma antigen (SCC-Ag), carcinoembryonic antigen (CEA), and carbohydrate antigen 19-9 (CA19-9) in patients with esophageal squamous cell carcinoma. In 112 primary cancer patients, the diagnostic sensitivity of CYFRA 21-1 (33.9%) was superior to SCC-Ag (28.6%), CEA (12.5%), and CA19-9 (6.3%). Levels of CYFRA 21-1 were closely correlated with TNM stage and wee below the cutoff value in all 21 patients with stage I disease. All 38 patients with a CYFRA 21-1 level over the cutoff value among the 80 patients who underwent esophagectomy had lymph node metastases (pN1). A correlation was found between CYFRA 21-1 levels and clinical response in serial measurements of 21 patients who received chemotherapy or chemo radiotherapy. Our findings suggest that CYFRA 21-1 is not useful for diagnosis, but that it is valuable for monitoring the efficacy of therapy.

Adult↗
PubMed1998

[Hepatic resection using glissonean pedicle transection].

The basics of hepatic resection using the glissonean pedicle transection method are presented. The portal triad continues from the hepatoduodenal ligament to the intrahepatic portion in the from of the glissonean pedicle, i.e., the artery, portal vein, and bile duct are Combined with connective tissue and sheathed by the peritoneum in the form of a fibroid bundle. The full length of the primary branches and the origin of secondary branches are located extrahepatically, and the trunk of the secondary and more peripheral branches have an intrahepatic course. The ramification pattern of the tertiary branches of each secondary branch varies by individual. The liver is nourished by the 3 secondary branches of the glissonean pedicle. Each secondary branch supplies one segment, and therefore the liver can be divided into 3 segments and the additional caudate area. The area supplied by each of the tertiary branches is cone shaped ("cone unit"). Each segment is composed of from 6 to 8 cone units. The standard method for hepatic resection is the segmental resection method, in which one secondary branch is transected. In cases of limited resection, the number of cone units to be resected is adjusted, and the tertiary branches which supply them must also be transected selectively through the hilar or parenchymal approach. The author has performed hepatic resection using the glissonean pedicle transection method in 834 consecutive patients with hepatocellular carcinoma with no trouble.

Carcinoma, Hepatocellular↗
PubMed1998

[Indications for and operative outcome of hepato-pancreatoduodenectomy in the treatment of carcinoma of the gallbladder].

The indications for hepatopancreatoduodenectomy (HPD) are still controversial. Opinion is divided especially concerning the need to perform pancreatoduodenectomy (PD) for lymph node dissection, with some investigators claiming that the peripancreatic lymph nodes can be dissected adequately without PD. Detailed studies of resected specimens in our department have shown that preservation of the head of the pancreas carries an increased risk of leaving behind cancer cells in small lymph nodes and ducts remaining in the peripancreatic region. We therefore perform HPD in all patients at increased risk for metastasis to peripancreatic lymph nodes, as indicated by subserosal invasion with distinct evidence of lymph node involvement, tumor location at the neck or both fundus and body of the gallbladder, and serosa exposure to tumor irrespective of tumor location and lymph node involvement. When the outcome was compared between HPD and hepatic resection plus dissection of peripancreatic lymph nodes (HR), we found that the operative results of HPD were poor with extended lobectomy plus PD because of high rates of postoperative complications and operative mortality. However, the results have gradually improved with the introduction of percutaneous transehepatic portal embolization and advances in perioperative care. Although overall there is no difference between HPD and HR in long-term outcome, the outcome with HPD is significantly better in node-positive patients and patients without hepatoduodenal ligament involvement, there by demonstrating the value of performing peripancreatic lymph node dissection by PD. However, there is no difference between HPD and HR in patients with hepatoduodenal ligament involvement, and attempts to develop other new and effective means of treatment should continue.

Gallbladder Neoplasms↗
PubMed1997

Difference in gene expression for matrix metalloproteinase-1 between early and advanced hepatocellular carcinomas.

The histological observation that well-differentiated cancer cells in early hepatocellular carcinoma (HCC) invade portal tracts and/or fibrous bands and that these fibrous tissues then disappear suggests the participation of matrix metalloproteinase-1 (MMP-1) in the degradation of fibrous tissue. To confirm this hypothesis, the authors investigated the localization of both the MMP-1 protein and its messenger RNA (mRNA) in early HCC immunohistochemically and by in situ hybridization using complementary DNA (cDNA) and synthetic antisense probe of MMP-1; they then compared the results with those in advanced HCC. MMP-1 gene transcripts and protein were observed in well-differentiated cancer cells of early HCC but not in moderately or poorly differentiated cancer cells. Thus, cancer cells producing MMP-1 in early HCC may destroy the portal tract tissue adjacent to the cancer lesion and/or the fibrous band of cirrhosis. These results seem to have demonstrated a difference in the mechanism of cancer growth and invasion between early and advanced HCCs.

Adult↗
PubMed1997

Prenatal determination of human platelet antigen type 4 by DNA amplification of amniotic fluid cells.

To predict a fetus at risk for neonatal alloimmune thrombocytopenia (NATP) caused by human platelet antigen (HPA)-4 incompatibility, we applied a sequence-specific polymerase chain reaction (PCR-SSP). We were able to determine the HPA-4 genotype of three infants at risk using amniotic fluid cells without the need for fetal blood sampling. The HPA-4 genotypes of amniotic fluid cells determined in this way were completely concordant with the genotype and phenotype of infants' venous blood samples obtained after delivery. Therefore, this technique is also convenient to a fetus at risk in the antenatal management of NATP induced by HPA-4 incompatibility.

Adult↗
PubMed1997

Apoptosis with FasL+ cell infiltration in the periphery and thymus of corrected autoimmune mice.

Fas (CD95) ligand (L) is a death factor that binds to its receptor, Fas, and induces apoptotic cell death, a crucial process in immunological tolerance. gld (generalized lymphoproliferative disorder) mice, which have a point mutation in the FasL gene, develop spontaneous systemic autoimmune syndromes characterized by hypergammaglobulinaemia and lymphoid hyperplasia owing to accumulation of abnormal B220+ CD3+ cells. Transplantation of wild-type (wt) bone marrow cells into old gld mice on the same strain background results in normalization of autoimmune syndromes. We characterized the cellular mechanisms (functionally and histologically) of the above phenomena in gld mice after bone marrow transplantation (BMT) to determine the role of apoptosis via Fas/FasL interactions in inducing and maintaining self-tolerance in vivo. Activated splenocytes from wt and BMT (wt to gld) mice showed significant cytotoxic activity against Fas transfectant cells while those from BMT (gld to gld) mice did not. Cells in the thymus, spleen and lymph nodes of gld mice uniformly upregulated Fas expression and were sensitive to Fas-mediated apoptosis compared with those in wt mice. Cells sensitive to Fas-mediated apoptosis in gld mice resided not only among abnormal B220+ CD3+ cells but also among conventional lymphocytes. More importantly, histological analysis revealed that cells in the spleen, lymph nodes and thymus frequently underwent apoptosis with infiltration of FasL+ cells in BMT (wt to gld) mice compared with BMT (gld to gld) mice. Our results indicated that apoptosis via Fas/FasL interactions can directly eliminate pathogenic cells responsible for autoimmunity in the periphery and possibly in the thymus in vivo.

Animals↗
PubMed1997

Stromal and blood vessel wall invasion in well-differentiated hepatocellular carcinoma.

We examined hepatocellular carcinomas (HCCs) that were smaller than 2 cm in diameter. Ninety-nine nodules from 65 patients were removed for treatment. The nodules were divided into four types (A, B, C and D) according to the following criteria: first, the appearance of the margin of nodules, distinct or indistinct; and second, cellular atypia, uniform or multiple as "nodules in nodule". In 45 indistinct margin nodules, 28 showed uniform atypia (type A) and 17 were of "nodules in nodule" (type B). As for 54 distinct margin nodules, 23 were "nodules in nodule" (type C) and 31 showed uniform atypia (type D). Cancer cell invasion was divided into three types: (1) stromal invasion into fibrotic tissue and/or portal tracts, (2) blood vessel wall invasion of portal veins or hepatic veins, and (3) tumor thrombus. The stromal and vessel wall invasion occurred almost at the same rate regardless of degree of atypia. This study shows that well-differentiated HCCs in which the cancer cells show only very slight atypia have the potential for metastasis to intrahepatic and other sites.

Adult↗
PubMed1997

[Immunohistological study of the nasal mucosa with reference to gamma delta-T cells].

The distribution of gamma delta-T cells (gamma delta-TCR positive cells) in nasal mucosa and polyps was studied in patients with nasal allergy and non-allergic patients. The biopsy specimens from the inferior turbinate and resected polyps were frozen at -70 degrees C and sliced at a thickness of 4 microns with a cryostat. Monoclonal antibodies (CD3 and TCR-gamma delta-1) and the Labelled Streptavidin Biotin method were used to detect T lymphocytes and gamma delta-T cells. The results were as follows: 1) The rate of gamma delta-T cells in the epithelium is higher than that in the lamina propria in patients with nasal allergy. 2) In non-allergic patients, on the other hand, the rate of gamma delta-T cells was almost the same in these layers. 3) The distribution of gamma delta-T cells in nasal polyps was uniform and their rate was relatively high. It has been reported that gamma delta-T cells can recognize a stress antigen such as heat shock protein. These cells are thought to play an important role in non-specific immunoreactions. This study suggests that gamma delta-T cells in the nasal mucosa play an important role also in specific immunoreactions.

Adolescent↗
PubMed1997

[Effect of percutaneous transluminal mitral commissurotomy on pulmonary function and on the pulmonary vasculature].

We evaluated the therapeutic effect of percutaneous transluminal mitral commissurotomy (PTMC) on pulmonary function, and the damage caused to pulmonary vasculature by transient occlusion of the mitral valve during PTMC in patients with mild mitral stenosis. Pulmonary function tests were done and serum thrombomodulin was measured in 6 patients before and after PTMC. The mean pulmonary arterial pressure and mean pulmonary arterial wedge pressure decreased significantly from the control values, and the decreases were proportional to the increase in the area of the mitral valve. VC, %VC, and DLco were in the normal range before and after PTMC but PEFR, FEV1%, FEV1, V50, V25, and V50/V25 were significantly higher after PTMC. Change in the area of the mitral valve correlated with the changes in FEV1% (r = 0.841), in V50 (r = 0.624), and in V25 (r = 0.697). The serum thrombomodulin levels before and after PTMC did not differ. We conclude that pulmonary dysfunction in patients with mild mitral stenosis MS is mainly due to an obstructive ventilatory defect, and that PTMC can correct this dysfunction without damaging the pulmonary vasculature.

Aged↗
PubMed1997

[The study for the surgical treatment on distal bile duct carcinoma].

The surgical result in 74 patients with resected distal bile duct carcinoma was reviewed to clarify the surgical strategy of distal bile duct carcinoma. The clinicopathological record was according to the General rules for surgical and pathological studies on cancer of biliary tract(the 3rd edition, edited by the Japanese society of biliary surgery). 58 patients underwent standard pancreatoduodenectomy and 16 patients had pylorus-preserving pancreatoduodenectomy. The curative resection was performed in 38 patients (51.3%). The overall 5-year survival rate (operated death included) was 35.8%. The 5-year survival rate in curative resection was 56.6%. The survival rate of patients with curative resection was significantly better than that of the patients with relative non-curative (p < 0.05) or absolute non-curative resection (p < 0.01). We concluded that the Long-term survival after surgical resection was mostly correlated with curability. To obtain curative resection, the free surgical margin of hw and ew was essential. As for free "hw", intraoperative frozen dissection was indispensable. For free "ew", the dissection of the soft tissues in retroperitoneum at the back of pancreas head was necessary. On the lymph node dissection, the lymph nodes of No 8, 12, 13, 14 should be removed.

Bile Duct Neoplasms↗