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H Taoka

Publications and source records attributed to H Taoka.

At least 19 recordsLinked to original sources
PubMed2000

Anatomy of the hepatic hilar area: the plate system.

To surgically manage hilar bile duct carcinoma successfully, it is important to be familiar with the principal anatomical variations of the biliary and vascular components of the plate system in the hepatic hilar area, because all the variations in the bile ducts and vessels occur in the plate system. The plate system consists of bile ducts and blood vessels surrounded by a sheath. There are three plates in the hilar area: the hilar plate, the cystic plate, and the umbilical plate. The bile duct and blood vessel branches penetrate the plate system and form Glisson's capsule in all segments of the liver, except for the medial segment. The right hepatic duct is usually (in 53%-72% of individuals) formed by the union of the anterior segmental duct and the posterior segmental duct in the hilar area. However, three other variations have been found in which these segmental ducts do not form the right hepatic duct. Few anatomical variations have been identified in the left hepatic duct, but confusion arises because of the variations in the medial segment ducts (B4) which join the left hepatic duct at different sites. In 35.5% of individuals they join the hepatic duct in the vicinity of the hilar confluence (type I B4 anatomy), and in 64.5% of individuals they join the left hepatic duct some distance away from the confluence (type II B4 anatomy). Because B4 is very close to the hilar confluence in type I, hilar bile duct carcinoma can easily invade B4 and, for that reason, for curative resection of hilar bile duct carcinoma, resection of S4a (the inferior part of the medial segment) should be considered along with the resection of extrahepatic bile duct and caudate lobe. Variations in the portal vein and hepatic artery are found in 16%-26% and 31%-33% of individuals, respectively. Because a considerable number of anatomical variations in the bile ducts and vessels persist in the hilar area, and the reported proportions of the different variations vary, it is necessary to have a good knowledge of the plate system and the variations in the bile ducts and blood vessels in the hilar area to perform safe and curative surgery for hilar bile duct carcinoma.

Bile Ducts↗
PubMed2000

Surgical anatomy of the bile duct branches of the medial segment (B4) of the liver in relation to hilar carcinoma.

In some patients, hilar bile duct carcinoma can easily spread to the bile duct branches of the caudate lobe (B1) as well as to the bile duct branches of the medial segment (B4), and resection of the inferior portion of the medial segment (S4a) is then required. It is therefore important to understand the detailed anatomy of the B4, its confluence patterns, and its relation to the B1 in order to be able to identify such patients. The confluence pattern of the B4 was studied in 141 specimens (68 adult cadavers and 73 liver casts) and the distance between the left bile duct branches of the caudate lobe (B11) and the B4 was measured in 56 of the 73 casts in which both B11 and B4 were present. Two main gross types of B4 were recognized: type I, in which B4 joined the left hepatic duct (LHD) close to the hilar confluence (35.5%), and type II, in which B4 joined the LHD far from the hilar confluence (54.6%). Analysis of the relationship between B11 and B4 revealed a mean distance between B11 and B4 of 8 mm in type 1, and 17 mm in type II. When the distance is less than 10 mm, B11 and B4 are considered to be located very close to each other, and in such individuals hilar bile duct carcinoma can infiltrate the B4 easily, thereby necessitating the resection of S4a, together with a caudate lobectomy for curative resection. Also, the confluence pattern of the B4 often creates a problem when the LHD is divided and reconstructed during hepatectomy, because of the numerous anatomical variations of the B4 itself. We therefore concluded that a good anatomical knowledge of the B4 and its relation to the B11 is essential in making the decision to perform S4a resection in selected patients with hilar bile duct carcinoma with the aim of curative resection.

Adult↗
PubMed1999

Leptomycin B inactivates CRM1/exportin 1 by covalent modification at a cysteine residue in the central conserved region.

The cellular target of leptomycin B (LMB), a nuclear export inhibitor, has been identified as CRM1 (exportin 1), an evolutionarily conserved receptor for the nuclear export signal of proteins. However, the mechanism by which LMB inhibits CRM1 still remains unclear. CRM1 in a Schizosaccharomyces pombe mutant showing extremely high resistance to LMB had a single amino acid replacement at Cys-529 with Ser. The mutant gene, named crm1-K1, conferred LMB resistance on wild-type S. pombe, and Crm1-K1 no longer bound biotinylated LMB. (1)H NMR analysis showed that LMB bound N-acetyl-L-cysteine methyl ester through a Michael-type addition, consistent with the idea that LMB binds covalently via its alpha, beta-unsaturated delta-lactone to the sulfhydryl group of Cys-529. When HeLa cells were cultured with biotinylated LMB, the only cellular protein bound covalently was CRM1. Inhibition by N-ethylmaleimide (NEM), an alkylating agent, of CRM1-mediated nuclear export probably was caused by covalent binding of the electrophilic structure in NEM to the sulfhydryl group of Cys-529, because the crm1-K1 mutant showed the normal rate for the export of Rev nuclear export signal-bearing proteins in the presence of not only LMB but also NEM. These results show that the single cysteine residue determines LMB sensitivity and is selectively alkylated by LMB, leading to CRM1 inactivation.

Amino Acid Sequence↗
PubMed1999

A novel nuclear export signal sensitive to oxidative stress in the fission yeast transcription factor Pap1.

Pap1, a fission yeast AP-1-like transcription factor, is negatively regulated by CRM1/exportin 1, the nuclear export factor. Pap1 was localized normally in the cytoplasm but was accumulated in the nucleus when Crm1 was inactivated by a temperature-sensitive mutation or by treatment with leptomycin B, a specific export inhibitor. Deletion of the C-terminal cysteine-rich domain (CRD) resulted in nuclear accumulation of Pap1, while a glutathione S-transferase-green fluorescent protein-CRD fusion protein was localized in the cytoplasm in a Crm1-dependent manner. Deletion and mutational analyses identified several important amino acids in a 19-amino acid region in the CRD as a nuclear export signal (NES). Strikingly, a cysteine residue (Cys-532), in addition to two leucines and an isoleucine, was important for the NES function and the presence of at least one of the two cysteine residues was essential. Unlike classical NESs such as the human immunodeficiency virus Rev NES, the Pap1 NES lost the function upon treatment with oxidants such as diethyl maleate. The oxidative stress response is conserved through evolution, as green fluorescent protein-fused proteins bearing the Pap1 NES expressed in mammalian cells responded to diethyl maleate. These results show that the hydrophobic amino acid-rich region containing two important cysteines in Pap1 serves as a novel NES, which is sensitive to oxidative stress.

Amino Acid Sequence↗
PubMed1999

Clinicopathological features and outcome of hepatic resection for intrahepatic cholangiocarcinoma in Japan.

As a result of an increasing number of studies on the surgical treatment of intrahepatic cholangiocarcinoma (ICC), knowledge of its biological characteristics has been accumulating. We analyzed the clinicopathological features and outcome of 36 of 48 surgical patients with histologically proven ICC (75.0%) who underwent hepatic resection between March 1979 and July 1998. According to tumor location, 12 patients had the central type and 24, the peripheral type. The incidence of portal vein tumor thrombus and lymph node metastasis was higher in the central type than in the peripheral type. All 12 patients with the central type had stage IV disease, and none of them underwent complete resection, whereas 12 of the 24 patients with peripheral type tumors had stage IV disease; complete resection was achieved in 12 of the 24 patients with peripheral type tumors (50%). Outcome after resection was significantly poorer in the patients with the central type. The macroscopic type of lesion in the resected specimens was the mass-forming type in 15 patients (41.7%), the mass-forming + periductal-infiltrating type in 15 patients (41.7%), the periductal-infiltrating type in 3 patients (8.3%) and the intraductal growth type in 3 patients (8.3%). The macroscopic tumor type was associated with mode of tumor spread and outcome. All 3 patients with the intraductal growth type are alive without tumor recurrence 26-138 months after surgery. The survival rate was much higher in the patients with the mass-forming type than in those with the mass-forming + periductal-infiltrating type. Importantly, the outcome in the 17 patients who underwent resection for stage IV-B disease and who accounted for 47.2% of patients with resection in the present series was very poor, almost the same as that in the 12 patients who did not undergo resection. By selecting patients based on the biological characteristics of the tumor and taking into account patients' quality of life, complete surgical resection can be performed safely and is associated with long-term survival.

Aged↗
PubMed1999

How accurate is helical computed tomography for clinical staging of pancreatic cancer?

BACKGROUND: Our goal was to determine if findings on an index computed tomography (CT) scan would correlate with survival in patients with pancreatic adenocarcinoma. We know that as this tumor extends out of the gland, survival decreases. Are there any CT findings that assess tumor extension sufficiently that also correlate with survival? Once identified, these CT areas would be the best factors to clinically stage patients. METHODS: Between 1993 and 1997, 160 patients with biopsy-proven adenocarcinoma of the pancreatic head were included if an index helical CT scan and clinical follow-up were available. All CT scans were reviewed by the same radiologist blinded for outcomes. CT scans were interpreted using a graded extension of tumor out of the pancreatic head in four areas: retroperitoneum (RP); anterior pancreatic capsule (S); portal/superior mesenteric veins (PV); and celiac/superior mesenteric arteries (A). Extension of tumor was graded as follows: Grade 0 (negative margin); 1 (suspicious); 2 (positive); or 3 (extensively involved). Also recorded and graded were signs of metastases: nodal enlargement > or =1.5 cm (N); and lesions consistent with hepatic metastases (H). Survival was compared between grades for each CT area using the methods of Kaplan and Meier and relative risk estimates of death (Cox regression models). RESULTS: Compared with grade 0, the following CT areas had significantly decreased survival curves: grade 1 (only S and A), grade 2 and 3 (RP, PV, S, A). N and H did not correlate with survival unless > or =1.5 cm nodes were in the liver or splenic hilum or there were multiple liver nodules. CONCLUSION: Although postoperative microscopic H or N involvement is a reliable prognostic sign, only extensive CT involvement of H or N predicts survival preoperatively. A better CT finding that predicts decreased survival preoperatively was extension out of the pancreatic head (especially S or A). Clinical methods of staging should use CT areas such as S, A, PV, and RP, and not H and N.

Adenocarcinoma↗
PubMed1997

[Intrahepatic bile duct carcinoma (cholangiocarcinoma)].

There is no high risk group for cholangiocarcinoma as there is for hepatocellular carcinoma, and it has a poor prognosis because many cases are diagnosed after it has become advanced. To date, there is no effective chemotherapy or radiation therapy for cholangiocarcinoma, and extended hepatectomy is the only effective treatment. In Japan, regional lymph node dissection and extended hepatectomy have been performed aiming at curative resection, but the 5-year survival in Japan is still low, only 26.1%. The Committee on the Japanese General Rules for the Clinical and Pathological Study of Primary Liver Cancer has divided macroscopic type into 3 patterns: mass-forming type, periductal infiltrating type, and intraductal growth type, to access prognosis on a common basis. According to these groups, our patients with the intraductal growth type had a good outcome, but patients with the mass-forming type and periductal infiltrating type had a poor outcome. Many papers have reported that the presence of lymph node metastasis makes the prognosis poor. Among our cases, the 5-year survival rate for all patients who underwent hepatectomy was 26.1% and the rate for patients positive for lymph node metastasis was 10.8%, as opposed to 45.1% for patients negative for lymph node metastasis. We examined the outcome according to histological type and found that based on the histological findings, the prognosis was increasingly poor in the following order: papillary adenocarcinoma, macrotubular carcinoma, microtubular carcinoma. To achieve curative treatment in the future it will be important to clearly define the extent of hepatectomy and determine the extent of lymph node dissection required, and clearly identify other prognostic factors.

Bile Duct Neoplasms↗
PubMed1994

[Comparative study of activity of daily living in the elderly between in Kahoku and in Yaku].

A comparative community-based study of physical activity in the elderly was carried out between two Japanese rural towns, Kahoku and Yaku. This study included a questionnaire about activity of daily living (ADL) and information-related functions in relation to lifestyle. Subjects were all the eligible elderly aged over 65 years of each community (1618 and 704 subjects in Kahoku and Yaku respectively). The ratio of the eligible elderly aged over 65 years were 32% in Kahoku and 2% in Yaku. The response rates were 91% in Kahoku and 51% in Yaku. Common findings in both towns were as below; 1) scores in ADL decreased with advancing age, 2) information-related functions were similar in each town, and between genders, 3) marital condition among males was similar in both towns, 4) ADL scores were higher in the financially rich group than in the poor one, 5) ADL scores were higher in female subjects whose husbands were alive than in widows, 6) ADL scores were higher in subjects who walked every day than those who did not, 7) ADL scores were lower in subjects who took medicine every day than those who did not, however, this finding did not apply to antihypertensive drugs, 8) ADL scores were higher in subjects who drank in beverages than in those who never imbibed. The different results between Kahoku and Yaku were supposed to be due to differences in lifestyle.(ABSTRACT TRUNCATED AT 250 WORDS)

Activities of Daily Living↗
PubMed1994

[Comparative study of blood pressure variability in the elderly in Kahoku and in Yaku].

A comparative community-based study of blood pressure (BP) variability in the elderly was carried out in the Japanese rural towns of Kahoku and Yaku. The prevalence of hypertension, orthostatic hypotension and use of antihypertensive drugs, effects of postute on BP and the "white coat" effect in BP were examined in each town. There was no difference in the prevalence of hypertension between in the two towns. Orthostatic increase in BP and pulse rate was more common in elderly females than in elderly males in both towns, indicating that standing itself was a load for subjects and activated sympathetic nervous tone in the female elderly. The prevalence of orthostatic hypotension was 8.5% and 12% in Kahoku and Yaku respectively, and the "white coat" effect on BP was demonstrated in the elderly in each town. In conclusion, we should take orthostatic change and the "white coat" effect into consideration in the evaluation of BP among the elderly.

Aged↗
PubMed1994

[Comparative study of serum lipids and other blood chemistry factors in the elderly in Kahoku and Yaku].

A comparative community-based study of serum lipids and other blood chemistry data in the elderly was carried out in two Japanese rural towns, Kahoku and Yaku. We studied the following blood chemistry factors; total proteins (TP), albumin (Alb), blood glucose (glucose), urea nitrogen (BUN), uric acid (UA), total cholesterol (T-Cho), high density lipoprotein (HDL-C) and lipoprotein (a) (Lp(a)). Subjects were the 312 eligible elderly aged over 75 years in Kahoku, and 172 similar elderly in Yaku. There were no significant differences in TP, Alb, glucose, BUN and UA of the elderly in the two areas. Mean HDL-C level was significantly lower and mean Lp(a) concentration was significantly higher in the elderly in Kahoku than in Yaku, Mean value of T-Cho did not differ significantly between the elderly in the two areas, however, the ratio of subjects whose T-Cho concentrations were over 220 mg/dl was significantly higher in Kahoku than in Yaku. These data suggested that the risk of atherosclerosis from the standpoint of view of serum lipids was higher in the elderly in Kahoku than in those in Yaku. Epidemiological data of Kochi and Kagoshima prefecture indicated that the mortality ratio from ischemic heart disease was higher in Kahoku than in Yaku, although that from cerebral infarction was lower in Kahoku than in Yaku. Comparative study of laboratory data in various districts is useful to investigate the relationship between lifestyle and diseases.

Aged↗
PubMed1994

[Comparative study of neurobehavioral function in the elderly between in Kahoku and Yaku].

A comparative study of neurobehavioral functions in the elderly was carried out between two Japanese rural towns, Kahoku and in Yaku. To evaluate of neurobehavioral functions, we used 1) Mini Mental State Examination (MMS), 2) Hasegawa Dementia Scale Revised (HDSR), 3) Kohs block design test, 4) Visuospatial cognitive performance score (VCPS), 5) Button Score (Button-S), 6) Up & Go test, and 7) Functional reach (FR). A questionnaire about ADL, information-related function and lifestyle was also done. Subjects consisted of all the eligible 332 elderly aged over 75 in Kahoku and 194 elderly aged over 75 in Yaku. In Kahoku, each function test had a significant correlation with age. However, in Yaku, the Up & Go, FR, MMS and HDSR results showed no significant correlation with age. Scores in cognitive function tests such as MMS, VCPS, and the Kohs test were better in kahoku than in Yaku, although scores in behavioral function tests such as FR were better in Yaku than in Kahoku. MMS, HDSR and Kohs tests significantly correlated with information-related function while Button-S, Up Go and FR tests had significant correlation one with ADL in both areas. Scores on function tests were better in the living-alone group and the group who had a daily work than in other groups in Kahoku. However, differences in scores in function tests between these two types of groups failed to reach a level of significance in Yaku. These data suggested that the difference in life-style influenced neurobehavioral functions in the elderly.

Activities of Daily Living↗
PubMed1994

[Comparative study of quality of life in the elderly between in Kahoku and in Yaku].

A comparative community-based study of quality of life (QOL) in the elderly was carried out between two Japanese rural towns, Kahoku and Yaku.QOL, which included the subjective sense of health, appetite, sleep at night, mood, memory, family relationships, friendship, economic condition, life satisfaction and happiness was assessed using a visual analogue scale (VAS) as well a Geriatric depression Scale (GDS), a variety of neurobehavioral function tests, and a questionnaire about activity of daily living (ADL). Subjects were all the eligible elderly aged over 75 years in both communities. Inter-rater reproducibility in VSA was more reliable than that in GDS. Life satisfaction and a subjective sense of happiness highly correlated with mood, family relationships, friendship and economic condition. GDS and VAS significantly correlated with family relationships, active participation in a group and economic condition, however, they did not correlated with age. The subjective sense of happiness correlated with ADL and steadiness of walk as assessed by neurobehavioral function tests. Living style correlated with VAS in the male elderly, but not female. Each score in VAS for family relationships, friendship, economic condition, life satisfaction and subjective sense of happiness was significantly higher in the elderly in Yaku than in Kohoku. The diseases which elderly people wanted to avoid were dimentia cancer, stroke, and cardiovascular disease in that order. In conclusion, QOL in the elderly population was influenced by disease, neurobehavioral functions, especially walking function, gender difference, lifestyle as well as cultural environment.

Activities of Daily Living↗
PubMed1991

A report of 5 cases of cystic bile duct carcinoma of the liver and proposal of a new classification.

Primary biliary cystadenocarcinoma of the liver is rare. Among 239 patients with primary liver cancer admitted to our service during the last 13 years, there were 5 cases of cystic bile duct carcinoma of the liver. Three of these were cystadenocarcinoma, one was adenocarcinoma arising from a liver cyst, and one was carcinoma of the intrahepatic bile ducts with cystic dilatation. A better classification of these entities seems necessary, and it is suggested that malignant cystic tumors of the liver should be divided into 3 groups: Group A is cystic adenocarcinoma, group B is bile duct carcinoma with primary or secondary intrahepatic bile duct, and group C is degenerative cyst formation by other types of malignant tumors. Cystic adenocarcinoma (Group A) can then be further subdivided into cystadenocarcinoma, cystadenocarcinoma with cystadenoma, and carcinoma in a simple cyst of the liver.

Adenoma, Bile Duct↗
PubMed1991

Experimental study on the pathogenesis of acute acalculous cholecystitis, with special reference to the roles of microcirculatory disturbances, free radicals and membrane-bound phospholipase A2.

To elucidate the pathogenesis of acute acalculous cholecystitis, the gallbladder was subjected to ischemia-reperfusion by simultaneously occluding the middle hepatic artery and the superior mesenteric vein in dogs, and the degree of inflammation and biochemical changes in the gallbladder mucosa were studied by varying the duration of ischemia or reperfusion. Ischemia alone did not induce cholecystitis either macroscopically and histologically, although it increased phospholipase A2 (PLA2) activity, content of lipid peroxide, and superoxide dismutase (SOD) activity in the mucosa with prolongation of the ischemic time. Cholecystitis was produced in all animals by 45-min ischemia followed by 90-min reperfusion as the shortest ischemia and reperfusion times. In this model, prolongation of the ischemic time increased the area of mucosal inflammation horizontally with increases of the PLA2 activity, content of lipid peroxide, and SOD activity, whereas by prolonging the reperfusion time the inflammation area spread deeper vertically toward the serosal side with significant increase in the mucosal PLA2 activity, content of lipid peroxide, and SOD activity. These results revealed that ischemia-reperfusion plays an important role in the pathogenesis of acute acalculous cholecystitis, causing the generation of free radicals and the activation of membrane-bound PLA2.

Acute Disease↗
PubMed1987

[Clinical study on the effect of 24-hour continuous intravenous infusion of CDDP in far-advanced and recurrent carcinoma of the gastrointestinal tract].

This clinical study was undertaken in order to evaluate the effect of CDDP on 43 patients with far-advanced or recurrent carcinoma of the gastrointestinal tract. For all these patients, CDDP at 100 mg/m2 had been administered by continuous intravenous infusion for 24 hours and repeated one to seven times at an interval of 3 to 4 weeks. The effect of this therapy was assessed according to the criteria of clinical evaluation of chemotherapy for solid cancers by Koyama and Saito. The response rate for both complete and partial response was 27.9% among all 43 patients, including 47.1% (8/17) for gastric cancer, 33.3% (1/3) for esophageal cancer, 25.0% (1/4) for hepatocellular carcinoma, 25.0% (1/4) for carcinoma of the gallbladder or bile duct, 20.0% (1/5) for pancreatic cancer and none (0/10) for colorectal cancer. In particular, a good response rate of 37.5% (3/8) was obtained for patients with recurrent tumor and one of 33.3% (6/18) for those with palliative resection of the primary tumor, which was much higher that the rate of 17.6% (3/17) for those without resection. As for the side effects of CDDP therapy, gastrointestinal symptoms were most frequently found in 78.3% of patients followed by bone marrow suppression in 15.2%, and abnormalities of hepatic and renal function in 4.3% and 4.3%, respectively. Consequently, 24-hour continuous intravenous infusion of CDDP was considered to be effective for far-advanced or recurrent carcinoma, especially in cases of gastric cancer.

Carcinoma, Hepatocellular↗
PubMed1987

[Significance of CA19-9 values in the feces of patients with colorectal carcinoma].

We measured CA19-9 value in feces of 119 cases with malignant disease, 78 cases with benign diseases and 36 healthy volunteers, and studied its usefulness for the diagnosis of digestive tract cancer. Mean value of CA19-9 in feces of healthy volunteer was 276.4 +/- 643.3 U/ml (mean +/- 2S.D.) and cut off value was defined as 1000 U/ml. The positive ratio of CA19-9 in feces of patients with malignant diseases as 44.5%. On the other hand, the mean of the false positive ratio was only 1.4% in benign diseases. Regarding to its breakdown, CA19-9 in feces revealed the highest positive ratio as 68% in colonic cancer. In colonic cancer, CA19-9 in feces showed a high positive ratio of 83% at advanced stage. Histologically, the positive ratios of CA19-9 in feces were higher, such as in more than 80% of the reaching degree of depth ss, a1, more than 82% of the disease due to higher parasites of lymph vessel ly1 and more than 95% of the metastasis of lymph node n1. Moreover, all CA19-9 in feces were positive in positive cases of CEA in serum.

Adult↗