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T Wakai

Publications and source records attributed to T Wakai.

At least 19 recordsLinked to original sources
PubMed2006

Number of positive lymph nodes independently affects long-term survival after resection in patients with ampullary carcinoma.

AIM: The nodal status is an established prognostic factor in ampullary carcinoma. The aim of this study was to compare the prognostic power of the anatomic location of positive nodes with that of the number of positive nodes. METHODS: Of 73 consecutive patients treated for ampullary carcinoma, 62 underwent pancreaticoduodenectomy with regional lymphadenectomy. A survival analysis of these 62 patients by nodal status was conducted retrospectively. A total of 1942 lymph nodes taken from the patients were examined histologically for metastasis. The location of positive regional nodes was classified into 4 categories, according to the Japanese staging system. The number of positive regional nodes was recorded for each patient. The median follow-up period was 124 months. RESULTS: Nodal disease was found in 31 patients, of whom 23 had 1-3 positive regional nodes and 8 had >or=4 positive regional nodes. Univariate analysis revealed that both the location (p<0.0001) and the number (p<0.0001) of positive nodes were significant prognostic factors. Multivariate analysis revealed that the number of positive nodes was an independent prognostic factor (p=0.007), while the location failed to remain as an independent variable. The median survival time was 59 months with a 5-year survival rate of 48% in patients with 1-3 positive nodes, whereas all patients with >or=4 positive nodes died of the disease within 29 months of resection (p=0.0001). CONCLUSION: The number, not the location, of positive regional lymph nodes independently affects long-term survival after resection in patients with ampullary carcinoma.

Adult↗
PubMed2004

High risk of gallbladder carcinoma in elderly patients with segmental adenomyomatosis of the gallbladder.

The clinical significance of adenomyomatosis of the gallbladder remains unclear. This study aimed to clarify the relationship between segmental adenomyomatosis and gallbladder carcinoma, and to elucidate the histogenesis of gallbladder carcinoma associated with segmental adenomyomatosis. A total of 4,560 consecutive patients underwent cholecystectomy. The specimens were examined grossly and histologically. Adenomyomatosis of the gallbladder was divided into segmental, fundal, and diffuse types. Sixty noncancerous gallbladders with segmental adenomyomatosis were examined for epithelial metaplasia. The incidence of gallbladder carcinoma was higher in patients with segmental adenomyomatosis (22/334, 6.6%) than in those without (181/4226, 4.3%; P=0.049). This difference was more marked among patients equal to or older than 60 years of age (15/96,15.6% versus 147/2407, 6.1%, respectively; P<0.001). The other types of adenomyomatosis did not show any significant increases in the incidence of gallbladder carcinoma. In all 22 patients with both segmental adenomyomatosis and carcinoma, the tumors developed only in the fundal mucosa. Epithelial metaplasia was more marked in the fundal mucosa of segmental adenomyomatosis than in the neck mucosa (P=0.003). Segmental adenomyomatosis is a high-risk condition for gallbladder carcinoma, especially in elderly patients. Epithelial metaplasia appears to be related to increased carcinogenesis in the fundal mucosa of segmental adenomyomatosis.

Adenomyoma↗
PubMed2003

Hepatitis viral status affects the pattern of intrahepatic recurrence after resection for hepatocellular carcinoma.

AIM: To define whether the patterns of intrahepatic recurrence after resection for hepatocellular carcinoma differ according to hepatitis viral status. METHODS: One hundred and eleven patients undergoing a curative resection for hepatocellular carcinoma were divided into three groups: the C-viral group (n=55), which tested positive for hepatitis C antibody; the B-viral group (n=32), which tested positive for hepatitis B surface antigen; and the non-B non-C (NBNC) group (n=24), which tested negative for both hepatitis B surface antigen and hepatitis C antibody. The long-term outcomes were analyzed retrospectively. RESULTS: The pattern of development of intrahepatic recurrence differed between the NBNC group and the other groups: the cumulative probability of intrahepatic recurrence reached a plateau at 2.4 years after resection in the NBNC group, while it continued to increase steadily in the hepatitis viral groups. The C-viral group showed a higher incidence of intrahepatic recurrence than the other groups by univariate (P=0.0306) and multivariate (relative risk=1.69, P=0.0429) analyses. Multiple intrahepatic recurrent lesions were more common in the C-viral group (P=0.0457). CONCLUSIONS: Multicentric carcinogenesis in the remnant liver was less common in the NBNC group than in hepatitis viral groups. Hepatitis C virus infection is a significant risk factor for intrahepatic recurrence after resection and is also associated with multiple intrahepatic recurrent lesions.

Adolescent↗
PubMed2002

Computed tomographic features of hepatocellular carcinoma predict long-term survival after hepatic resection.

AIM: To evaluate the potential of computed tomographic features of hepatocellular carcinoma as prognostic factors. METHODS: Medical records for 112 patients who had undergone a partial hepatectomy for hepatocellular carcinoma were retrospectively analyzed. The largest hepatic tumour in each patient was classified by pre-operative computed tomographic features as lobular configurations with indentations showing an acute angle, or non-lobular configuration without such indentations. RESULTS: Twenty-six tumours were lobular and 86 were non-lobular. The outcome after hepatectomy was significantly worse in patients with lobular tumours (cumulative 5-year survival rate of 19.9%) than with non-lobular ones (that of 75.2%) (P<0.001). Cox's proportional hazards model showed computed tomographic features (P=0.0025), cirrhosis (P=0.0033), and tumour size (P=0.0412) to be independent prognostic factors. A lobular configuration was associated with satellite nodules (P<0.001), portal vein invasion (P=0.021), and extrahepatic tumour relapse (P=0.006). CONCLUSIONS: Computed tomographic features represent a strong prognostic factor in patients undergoing partial hepatectomy for hepatocellular carcinoma, and are likely to accurately reflect the tumour biology. Configuration, size of the hepatic tumour and presence of cirrhosis are the most important prognostic imaging findings in these patients.

Carcinoma, Hepatocellular↗
PubMed2001

Early gallbladder carcinoma does not warrant radical resection.

BACKGROUND: This study was designed to address whether gallbladder cancer invading the muscle layer (stage pT(1b)) is a local disease and whether radical resection is necessary. METHODS: A retrospective analysis of 25 patients with pT(1b) gallbladder tumours, 13 of whom underwent simple cholecystectomy and 12 radical resection with regional lymph node dissection, was performed. A total of 147 regional lymph nodes was examined for metastasis. The median follow-up time was 95 months. RESULTS: No patient had blood vessel or perineural invasion on histology. Lymphatic vessel invasion was seen in one patient. Both overt metastasis and micrometastases were absent in all lymph nodes examined. Overall 10-year survival was 87 per cent. The outcome after simple cholecystectomy was comparable to that after radical resection (P = 0.16). Two patients who underwent radical resection died from tumour relapse in distant sites. CONCLUSION: Most pT(1b) gallbladder carcinomas spread only locally. Additional radical resection is not necessary when the depth of invasion of gallbladder carcinoma is limited to the muscle layer after simple cholecystectomy.

Adult↗
PubMed1999

Anomalous insertion of the right hepatic duct into the cystic duct: report of a case diagnosed before laparoscopic cholecystectomy.

Although an aberrant hepatic duct entering the cystic duct is not especially rare, the main right hepatic duct entering the cystic duct is extremely rare, with only six cases reported thus far. All of the reported patients underwent open cholecystectomy, during which one patient received a bile duct injury. The anomaly was unsuspected preoperatively in all of these cases. We report an additional patient with this anomaly, the first such case diagnosed before laparoscopic cholecystectomy using direct cholangiography. Cholangiography may be mandatory whenever biliary anomalies are suspected during laparoscopic cholecystectomy. As the right hepatic duct entering the cystic duct can lead to ductal injury, this anomaly should be kept in mind when performing laparoscopic cholecystectomy.

Adult↗
PubMed1998

Protein kinase C controls the priming step of regulated exocytosis in adrenal chromaffin cells.

1. To investigate the mechanism whereby protein kinase C enhances secretory function in adrenal chromaffin cells, we examined the effects of 12-O-tetradecanoylphorbor-13-acetate (TPA) on Ca(2+)-induced catecholamine release from digitonin-permeabilized cells, resolving the release into a MgATP-dependent priming step and a MgATP-independent Ca(2+)-triggered step. Treatment with TPA selectively potentiated the priming activity of MgATP, with little increase in the MgATP-independent release. The potentiation by TPA of the MgATP-dependent priming was blocked by [Ser25]protein kinase C(19-31), a specific substrate of protein kinase C. Gö 6976, an inhibitor selective for protein kinase C alpha and beta isoforms, also blocked the potentiation by TPA. These results suggest that activation of protein kinase C, probably the alpha isoform, potentiates the MgATP-dependent priming step. 2. The antibody raised against GAP-43, a known substrate of protein kinase C, also potentiated the MgATP-dependent priming. The effect of TPA and that of the anti-GAP-43 antibody were not additive. Calmodulin, which binds to GAP-43 and inhibits its phosphorylation by protein kinase C, abolished the effect of TPA. Thus, the present results suggest that protein kinase C potentiates MgATP-dependent priming, at least in part, through phosphorylation of GAP-43.

Adenosine Triphosphate↗
PubMed1998

Malignant fibrous histiocytoma metastases to the small intestine and colon presenting as an intussusception.

A case of malignant fibrous histiocytoma metastases to the small intestine and colon presenting as an intussusception is described. Although malignant fibrous histiocytoma is the most common soft tissue sarcoma in late adult life, GI involvement has rarely been reported. The review of both our case and eight cases in the English-language literature suggests that GI involvement from malignant fibrous histiocytoma occurs most frequently in the small intestine (six of nine) and that two major clinical manifestations of GI involvement are GI bleeding (five of nine) from ulcerated tumors and intussusception (two of nine) led by polypoid tumors.

Colonic Neoplasms↗
PubMed1997

Decreases in peripheral-type benzodiazepine receptors in postmortem brains of chronic schizophrenics.

We measured the peripheral-type benzodiazepine receptors (PBRs), a marker of gliosis, in 26 brain areas (cerebral cortex, thalamus and extrapyramidal system) of the postmortem brains of 13 chronic schizophrenics and 10 controls, using [3H] PK 11195 as a ligand for the receptor assay. The specific [3H] PK 11195 binding was significantly decreased in three brain areas (superior parietal cortex, primary visual area and putamen) of schizophrenics, although there were no changes in the binding in the other brain areas. Scatchard analysis revealed that there were decreases in both the Bmax and Kd of [3H] PK 11195 binding in the brain areas. These results were almost in accordance with a number of neuropathological studies reporting that there was no change or reduction in glial cells in the brain regions of schizophrenics and suggested that the decreased density of PBRs in the brain may be involved in the pathophysiology of schizophrenia, associated with reduced production of neurosteroids coupled to PBRs.

Adult↗
PubMed1996

Colorectal carcinoma metastases to the liver. Does primary tumor location affect its lobar distribution?

BACKGROUND: There is considerable evidence that blood returning from different abdominal organs does not mix completely but maintains streamline flow in the portal vein. This study tested the hypothesis that the location of primary colorectal carcinoma affects the intrahepatic distribution of liver metastases according to streamline flow in the portal vein. METHODS: Eighty-five patients with histologically verified liver metastases from colorectal carcinoma underwent potentially curative hepatectomy. Primary tumor location was the right-sided colon in 18 patients and the left-sided colon in 67. The liver was divided into two lobes by Cantlie's line. RESULTS: A total of 195 metastatic deposits were resected: 135 in the right lobe and 60 in the left. In the right-sided colon carcinoma group, 29 deposits were in the right lobe and 3 in the left. In the left-sided colon carcinoma group, 106 deposits were in the right lobe and 57 in the left. The pattern of lobar distribution was significantly different in the two groups (P = 0.003). CONCLUSIONS: Right-sided colon cancers selectively involve the right lobe, while left-sided tumors involve the entire liver, considering the ratio of weights of the right to left lobe is 2:1. This difference suggests that primary tumor location affects the pattern of lobar distribution of colorectal carcinoma liver metastases according to streamline flow in the portal vein.

Carcinoma↗
PubMed1996

Hepatocellular carcinoma associated with precirrhotic primary biliary cirrhosis successfully treated by a right hepatic lobectomy: report of a case.

We report herein the case of a 69-year-old woman in whom hepatocellular carcinoma (HCC) arising in the precirrhotic phase of primary biliary cirrhosis (PBC) was successfully managed by a right hepatic lobectomy. The patient, who had never received a blood transfusion, had a 4-year history of asymptomatic PBC of Scheuer's histological classification stage II. Abdominal computed tomography (CT) revealed a mass measuring 4.0 cm in the right hepatic lobe, and a right hepatic lobectomy was performed in consideration of her good liver function and the deep location of the tumor in the right lobe. The patient has remained well without any evidence of recurrent disease for 4 years since her operation. A review of the literature revealed only two cases of successful partial hepatectomy, but none of major hepatectomy. Most of the reported cases had been treated with transcatheter arterial embolization (TAE) and were associated with poor survival. Our experience of this patient indicates the potential value of hepatectomy as an alternative to TAE in selected patients with resectable disease and good hepatic function.

Aged↗
PubMed1992

[Maternal carriage and vertical transmission of group B Streptococcus (GBS)].

The pneumonia, sepsis and meningitis are common diseases of GBS infection in infants. There are early-onset and late-onset types in this disease, the result of the infection is unknown. M. Sugiyama reported that M9 is a new type of GBS in Japan in 1989. Analysis of GBS typing and serum specific antibody concentrations of the type are simple with new technics. By studying the infants' contamination we discovered that GBS appeared to originate from mother-infant sources. The infants were followed for a year. 52% of the infants had GBS contamination in their throat or stool. The most common type was Ia, followed by III, JM9 and NT6. Those types without III type had been present for more than 9 months in the infant. The contamination term of Ia or III type in infants correlated with the blood specific antibody concentration of the type.

Carrier State↗
PubMed1991

[Occurrence of Escherichia coli in urinary tract infection].

Regarding P-fimbriae, K1 antigen, sero O-type and factors on the host (age, sex and morbidity) with are the pathogenic factors in E. coli, an assessment has been made as to what relations these factors have in urinary tract infection. By age, cases of P-fimbriae is seen in large numbers among pregnant women and infants but less among the people aged 16-30. A similar trend was observed regarding K1 antigen. An assessment made by sex show a trend that E. coli which carries P-fimbriae tends to emerge frequently in males. By morbidity, P-fimbriated strain was seen in many severe cases among pregnant women and infants. The fact has become evident further as a result of making an investigation with K1 antigen added. However, the result of an assessment made in adult cases showed that P-fimbriae was seen frequently in simple cystitis conversely. As the reason for P-fimbriae being observed more in males, participations of immunological stage and anatomical factors on the host side in the pathogenicity was resumed, and the main cause that P-fimbriae is seen more in severe pregnant and infantile cases was presumed to be vesicoureteral reflux. Regarding group sero O-type and morbidity, the types reported so far were detected also at our hospital, but a very interesting finding we have obtained was that the stains P-fimbriae and K1 antigen were observed in types 2, 12, 18 and 75.

ABO Blood-Group System↗
PubMed1978

Purification of rat prolactin releasing factor by gel filtration.

Pregnant rat hypothalamic fragments were extracted with 30 mM Tris-HCl buffer at pH 7.8, subjected to enzymatic digestion, and applied to gel filtration on Sephadex G-25 for purification of the prolactin releasing factor. Effect of the eluted fractions on the release of prolactin were tested by the determination of serum and pituitary prolactin after the injection in lactating rats. Prolactin was estimated by radioimmunoassay. One fraction (tube number 61--73) eluted later than synthetic ACTH enhanced release of prolactin 30 min after injection, but other fractions had no effect on the release of prolactin. Prolactin releasing factor would be quantitatively predominant over prolactin inhibiting factor in pregnant rat.

Animals↗
PubMed1976

Relationship between prolactin secretion and hypothalamic prolactin releasing factor in pregnant and puerperium rats.

The present study attempted to elucidate stimulatory factor(s) in the rat hypothalamus which controls prolactin secretion from the anterior pituitary. Rat serum prolactin was elevated so much in late pregnancy that we prepared the hypothalamic extract of late pregnant rats. Prolactin levels in serum and pituitary by radioimmunoassay. After injection of this extract into a lactating rat 48-60 hr after delivery, the serum prolactin level was elevated significantly one to four hr later and the pituitary prolactin level declined two hr later. On the other hand, the hypothalamic extract of normal female rats prepared in a similar manner inhibited prolactin secretion from the anterior pituitary in the lactating rat as described by other authors. These data indicate that the prolactin releasing factor may consist in the hypothalamus of late pregnant rat, and be predominant over the prolactin inhibiting factor during late pregnancy. Prolactin secretion was also investigated in lactating and non-lactating puerperium rats. Prolactin in serum and pituitary declined with days after delivery in non-lactating rats, but not in lactating rats. The presumed factor for such prolactin release in lactating rats is considered to be the prolactin releasing factor.

Animals↗
PubMed1975

[Prolactin releasing action of the hypothalamic extract in last stage of pregnant rats (author's transl)].

Regulation of prolactin secretion in pituitary is considered to be mostly carried with the action of prolactin inhibiting factor in hypothalamus. We have investigated on the subject of prolactin releasing factor in the hypothalamus of rats in last stage of pregnancy using puerperal and ovariectomized rats as recipients. After prepared the cell-free system of pregnant rat hypothalamus with sonic oscillator, supernatant was produced by ultracentrifuge (25,000 X g, 30 min.) and utilized for the experiments. When the extract was injected intramuscularly to puerperal rats (48-60 hours after delivery), serum prolactin values increased gradually to 3 times of control values, but pituitary prolactin values showed the variation with decrease and recovery. The control values were obtained by determination after injection of cerebral cortical extract to puerperal rats. After administration of a extract of non-pregnant rat hypothalamus to puerperal rats, serum prolactin values decreased and pituitary prolactin values increased antagonistically. In the ovariectomized rats pretreated with estradiol and progesterone, serum prolactin values increased in 1 hour after administration of the extract of pregnant rat hypothalamus, but pituitary prolactin values did not show any variation. The present experiment suggests that the prolactin secretion promoting factor exists in the hypothalamus of pregnant rats and predominates over as compared with PIF in last stage of pregnancy.

Animals↗