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T Hirota

Publications and source records attributed to T Hirota.

At least 235 records · Page 13Linked to original sources
PubMed1985

A new glucocorticoid receptor species: relation to induction of tryptophan dioxygenase by glucocorticoids.

When rats were treated with a high dose (greater than or equal to 20 micrograms/100 g BW) of dexamethasone, their liver cytosol showed a predominant peak of specific binding protein of glucocorticoid eluting with 0.13-0.14 M NaCl on diethylaminoethyl cellulose chromatography. On the other hand, when rats were treated with a low dose (approximately 2 micrograms/100 g BW) of dexamethasone, the cytosol showed only the same peak as that of untreated rats, which is widely thought to be that of the typical glucocorticoid receptor. The appearance of the new binding peak depended both on the dose of hormone and the time (from 30 min to 20 h) after dexamethasone treatment; it disappeared 40 h after treatment. A peak similar to that in the cytosol also appeared in the nuclear fraction after treatment with a high dose of hormone. The glucocorticoid-inducible enzymes, tryptophan dioxygenase [(TO) EC 1.13.11.11] and tyrosine aminotransferase (EC 2.6.1.5) were assayed as physiological markers of receptor function. TO induction correlated well with the appearance of the new binding peak in terms of dose- and time dependence on glucocorticoid, whereas tyrosine aminotransferase induction did not. The new peak of glucocorticoid-binding protein detected in the cytosol and nuclear fractions may thus represent the glucocorticoid receptor species involved in TO induction, physiological changes under stress, and pharmacological changes after therapy with high doses of glucocorticoid hormones.

Animals↗
PubMed1985

Simultaneous purification and properties of dehydropeptidase-I and aminopeptidase-M from rat kidney.

Two peptidases, dehydropeptidase-I and aminopeptidase-M were solubilized from rat kidney microsomes by treatment with papain and separated by DE-52 ion exchange chromatography. Each enzyme was further purified by Sephacryl S-300 gel filtration and affinity chromatography on Con-A Sepharose. Purified dehydropeptidase-I and aminopeptidase-M were homogeneous by SDS-polyacrylamide gel electrophoresis, and their molecular weights were estimated by gel filtration to be 148,000 and 240,000, respectively; both being homodimer, with a 78,000 subunit for the former and a 120,000 subunit for the latter. Both dehydropeptidase-I and aminopeptidase-M were capable of hydrolyzing L-leucyl-L-leucine with a Km valve of 1.1 mM and 1.7 mM, respectively, although the hydrolyzing activity of aminopeptidase-M was much higher than that of dehydropeptidase-I. Aminopeptidase-M was inhibited by bestatin, and dehydropeptidase-I was significantly inhibited by cilastatin. Dehydropeptidase-I catalyzed the conversion of leukotriene D4 to E4 and the hydrolysis of L-cystinyl-bis-glycine, but aminopeptidase-M did not to any appreciable extent. The physiological significance of dehydropeptidase-I was pointed out and discussed.

Aminopeptidases↗
PubMed1985

[Coexisting malignant lymphoma and advanced adenocarcinoma of the colon--a case report].

Although it is not uncommon to find multiple malignant neoplasms in the same organ, the incidence of synchronous malignant lymphoma and colonic adenocarcinoma has been very rare. This a case report involving a 52-year-old woman in whom malignant lymphoma actually arose within the same segment in which colonic adenocarcinoma was present. Under the diagnosis of advanced adenocarcinoma, she had been treated by right hemicolectomy. However, she developed intestinal obstruction about a month later. At the second surgery for this latter condition, cytologic examination of ascitic fluid revealed many malignant lymphoma cells. In spite of antilymphoma chemotherapy, the patient's condition became progressively worse during the subsequent five-month period, and she died of recurrent malignant lymphoma.

Adenocarcinoma↗
PubMed1985

Gastric cancer risk factors: a case-control study based on medical records.

Four hundred and sixty gastric cancer patients who had undergone operation at the National Cancer Center Hospital and an equal number of age-matched controls were analyzed in order to estimate the influence of gastric cancer family inheritance and cigarette smoking habit. Relative risks for cigarette smoking habit, for gastric cancer family inheritance and for both were 2.88, 1.67 and 4.12, respectively. Earlier age of onset of gastric cancer was observed in the gastric cancer cases with both risk factors as compared with the other patients.

Adult↗
PubMed1985

[Difference in clinical treatment between patients histologically diagnosed as group III by the old and new "group classifications" of gastric biopsy].

Since 1971, when the first draft of the "Group Classification", which classifies the atypism of histological structure in biopsy specimens of the stomach, was proposed by the Japanese Research Society For Gastric Cancer, this classification has come into wide use in Japan. It was, however, revised in 1983, and, according to the revised classification, group III was defined as general histological findings in which it is difficult to make a differentiation between benign and malignant by biopsy specimens. Consequently, the new group III includes, various borderline histologies, in addition to the old group III, which had been defined as the histological features corresponding to those observed in gastric adenoma in biopsy specimens. At the National Cancer Center Hospital, 13,909 gastric biopsies were performed during the period between 1973 and 1982. By retrospective review of these, histological findings in 247 lesions of 231 cases corresponded to group III by the old classification (adenomatous type) and in addition to these, 54 lesions of 54 cases to group III by the new classification (non-adenomatous type). We compared the endoscopic and pathological features between the two types, and the following results were obtained: The false-negative rate of malignancy in the non- adenomatous type (24%) was much higher than that in the adenomatous type (6%). The difference between the two may suggest that, with the adoption of the new group classification, clinical treatment of the patients with group III becomes more complicated due to the increase of the false-negative rate. Endoscopically, most (84%) of the lesions in the adenomatous type were seen as polypoid, while in the non-adenomatous type, depressed lesions were dominant (80%). And, endoscopic details of the polypoid or depressed appearances were mostly different between the two types. These nuances of endoscopic appearance between adenomatous and non-adenomatous types are applicable to decisions regarding, adequate clinical treatment for patients diagnosed as group III by the new "group classification." Good communication between the endoscopist and pathologist is indispensable.

Adenoma↗
PubMed1984

A monoclonal antibody reactive with gastric carcinoma.

A monoclonal antibody reactive with gastric carcinomas of the stomach was established. This antibody reacted with 88% (15/17) of the scirrhous carcinomas, and 75% (6/8) of the well differentiated adenocarcinomas of the stomach tested, but did not react with normal gastric mucosa or various other normal tissues, with the exception of the mucosa of the large intestine.

Adenocarcinoma↗
PubMed1984

Malignant peripheral nerve tumors: a clinicopathological and electron microscopic study.

Sixteen cases of malignant peripheral nerve tumors that were recorded in the files of the Department of Orthopedics, National Cancer Center Hospital, Tokyo, between 1972-July 1983 were studied clinicopathologically. The patients' ages ranged from 24-51 years, and both sexes were affected equally. Histologically, in 13 cases of nerve sheath tumors the tumors were spindle-cell type, two of these patients had manifestation of multiple neurofibromatosis (von Recklinghausen's disease). One malignant epithelioid schwannoma was found to arise from the tibial nerve. Other two cases were of primitive neuroectodermal tumors (primary malignant peripheral neuroblastoma) which showed rosette formation. The common primary symptoms in all patients were a noticeable mass which increased in size over a variable period of time, with or without associated pain and tenderness. Ultrastructural findings of spindle-cell type (in 7 tumors examined) and epithelioid type (1 tumor) showed evidence of Schwann cell differentiation of the tumors in all cases. Immunohistochemically, by the PAP method (Sternberger), staining for S-100 protein was positive in 3 of 14 tumors. Ultrastructural findings in two S-100 protein-positive cases showed evidence of Schwann cell differentiation better than the S-100 protein-negative cases, such as pronounced interdigitation of cytoplasmic processes, presence of fibrous long-spacing collagen and well-developed basal lamina. Local recurrence occurred in nine patients, and metastasis was found in five. The total 5-year survival rate was 58.5%. Tumors associated with multiple neurofibromatosis and primary peripheral neuroblastomas had the worst prognosis. Complete removal of the tumor by means of wide excision as primary treatment seemed to be the most important factor in decreasing the morbidity and mortality rates.

Adult↗
PubMed1984

Distribution of blood group antigens and CA 19-9 in gastric cancers and non-neoplastic gastric mucosa.

The distribution of blood group ABH antigens, their precursor I(Ma) antigen, Lewis a antigen and monoclonal antibody-defined tumor-associated antigen CA 19-9 in gastric cancers and their surrounding non-neoplastic mucosa was studied by using immunohistochemical methods. ABH antigens were localized in the foveolar epithelium except for a few cases presumed to be non-secretors, but ABH antigens were lost focally from metaplastic mucosa. In contrast, Lewis a and I(Ma) antigens were present in the foveolar epithelium of non-secretors and metaplastic mucosa where ABH antigens were not detected. Gastric cancers also showed focal loss of ABH antigens and gain of Lewis a and I(Ma) antigens, and the cancer cells showed marked heterogeneity in antigen expression compared with non-neoplastic mucosa. Expression of incompatible blood group antigen (A-like antigen) reactive with monoclonal anti-A antibody was also detected in cancer cells of blood group O and B cases. CA 19-9 (sialylated-Lewis a) was detected in 62% of gastric cancers and in the restricted areas of gastric mucosa where Lewis a was positive.

ABO Blood-Group System↗
PubMed1984

Binding of bile acids with rat colon and resultant perturbation of membrane organization as studied by uptake measurement and 31P nuclear magnetic resonance spectroscopy.

The mode of interaction of deoxycholate (DOC) or lithocholate (LC) with F344 rat colon was examined by measurements of uptake, 31P nuclear magnetic resonance (NMR) spectroscopy and observation of morphological changes. DOC as well as LC was taken up by the colon in a nonsaturable manner with respect to concentration and time, up to 30 min. None of several metabolic inhibitors reduced the uptake of the bile acids, nor did pretreatment of colon segments with chloroform-methanol (2:1, (v/v), heat or trypsin. Further, the bile acids were not transported by the colon against concentration gradients, and they were bound to both the mucosa and serosa equally. From these findings, it is concluded that the bile acids are transported in a passive manner, and no specific receptor for them is contained in colonic mucosa. The uptake of the bile acids by the colon varied with temperature and was related to the fluidity of the colonic membranes. The extent of uptake of dehydrocholate and taurocholate, which do not induce ornithine decarboxylase (ODC) activity, was almost the same as that of LC. The 31P NMR spectra of the colonic mucosal cells indicated that the proportion of the bilayer structure is increased by 0.5 mM DOC. Among a variety of bile acids examined, the extent of membrane alteration was in parallel with the extent of ODC induction. Treatment of the colonic mucosa with 0.5 mM DOC caused marked degeneration of the surface but not the deeper layers of the mucosa. Thus, physiological concentrations of bile acids influence the membrane organization of the colonic mucosa in a nonspecific manner that is possibly related to the tumor-promoting activity.

Animals↗
PubMed1984

A clinicopathologic study of carcinoma of the papilla of Vater.

With a view to clarify the concept of early carcinoma of the papilla Vateri, we examined the records of 26 patients who were treated at the National Cancer Center Hospital in the past 22 years. The following three factors were considered prognostically important for the identification of carcinomas at early stages: Histologically, 1: cancerous infiltration should not reach the proper muscle layer of the duodenum (d-factor); 2: no infiltration into the pancreas should be observed; 3: no metastasis to lymph nodes should be found. Factor-1 (d-factor) is the most important of these. Therefore early carcinoma of the papilla Vateri should be defined at present as that in which cancerous infiltration is limited to within the sphincter of Oddi. For the early diagnosis of carcinoma of the papilla Vateri, screening should be performed by ultrasonography, and when abnormalities are detected, endoscopic inspection of the duodenum and endoscopic retrograde cholangiopancreatography should be performed. Moreover, it is very important to read carefully the radiograms of the areas near the papillary regions of the duodenum in routine upper-digestive tract X-rays.

Aged↗
PubMed1984

A clinical and histopathological study of gastric polyps in familial polyposis coli.

Fundic gland area gastric polyps in familial polyposis coli (FPC) were compared with those in non-familial polyposis coli clinicopathologically to elucidate their histogenetic and biological characteristics. Some differences were observed in age, sex, and radiological and endoscopical features. Although the polyps were similar histologically, they showed an apparent histochemical difference between the two groups in periodic borohydride technique/potassium hydroxide/periodic acid-Schiff stain which demonstrates O-acylated sialic acid. The superficial and foveolar epithelium of the polyps was positive in 10 of 12 familial polyposis coli cases, while the epithelium was positive in only one of 13 non-familial polyposis coli cases with the same staining. These results suggest differences between the two groups in the degree of epithelial intestinal metaplasia. The presence of gastric polyps with O-acylated sialic acid therefore indicates the necessity of examination of the colorectum.

Adolescent↗
PubMed1984

Superficial carcinoma of the esophagus coexisting with esophageal leiomyoma: a case report and review of the Japanese literature.

A case of superficial spreading squamous cell carcinoma located just over a leiomyoma is presented. The patient complained of slight dysphagia and an esophagogram showed an elevated tumor in the middle thoracic esophagus. Esophagoscopy revealed an ulcerative mucosal lesion over the elevated lesion and biopsy showed that the lesion was a squamous cell carcinoma. Blunt dissection of the esophagus with esophago-gastro-anastomosis was performed. There was neither lymph vessel invasion nor lymph node metastasis. His post-operative recovery was satisfactory and he is doing well two years after the operation. A review of the Japanese and English literature revealed that a few cases of esophageal carcinoma coexisting with esophageal leiomyoma have been reported. There was no report of superficial esophageal carcinoma coexisting with esophageal leiomyoma. This is the first report of the coexistence of these two lesions, and esophagoscopy is necessary to find a superficial esophageal carcinoma coexisting with esophageal leiomyoma.

Adult↗
PubMed1984

Chronological changes in the morphological features of early gastric cancer, especially recent changes in macroscopic findings.

At the National Cancer Center, 1,300 patients with early gastric cancer were operated on during a period of 21 years, from 1962 to the end of May 1983, and the chronological sequence of the pathological features was analyzed by dividing the 21 years into five periods (I approximately V). The number of elderly patients, especially those above the age of 70 years increased with time, reaching about 20% of all patients in the later period. As to the CMA classification, lesions in A region (antral region) tended to increase, reaching 32.8% in the last period. Lesions on the anterior and posterior wall increased, reaching 20.2% and 30.5%, respectively. Lesions on the greater curvature side were almost unchanged in frequency. The depressed type of carcinoma tended to increase in frequency in the later period, accounting for 75.3% of the total. The depressed type lesions, especially those consisting mainly of IIc element, were therefore subdivided into deep IIc and shallow IIc. In the later period, shallow IIc or not readily detected indistinct IIc increased markedly, reaching 83.3% in Period V. In the initial period, 40% of the lesions were larger than 5 cm. In the later period, lesions larger than 5 cm decreased to 10%, and more than 40% were 2 cm or smaller. Histologically, differentiated and undifferentiated types were found at almost the same frequency. In the later period, the differentiated type became more frequent, reaching as much as 58.2%. Ulcerative lesions (presence of ulcers or ulcer scars in the cancerous lesions) comprised more than 90% of depressed type early gastric cancer, but gradually decreased to 71.9% in the later period. From these findings, early gastric cancer may be said to be changing. Factors contributing to such changes were studied with reference to the progress and multiplication of diagnostic techniques, changes in age composition of the population and changes in environmental factors.

Adult↗
PubMed1984

Diagnosis of early gastric cancer seen as less malignant endoscopically.

In order to make the endoscopic diagnosis of early gastric cancer more accurate, we determined the endoscopic and clinicopathological characteristics of the 129 cases of early gastric cancer with less malignant appearance among the 978 cases of the disease with a solitary lesion detected at the National Cancer Center Hospital during the period between 1962 and 1981. According to findings required to make a differential diagnosis, the endoscopic appearance of the 978 cases were divided into the following four groups: 170 cases of polypoid, 587 of ulcerative, 119 of gastritis-like and 102 of advanced cancer-like. Among the four groups, the frequency of cases with less malignant appearance was quite high in the gastritis-like group. The lesion in this group was defined as the cancerous lesion which shows only superficial mucosal abnormality, not associated with any polypoid or ulcerative components. Chronologically, it has been rapidly increasing in recent years. These two paradoxical phenomena in the gastritis-like group, that is, "high frequency of less malignant appearance" and "increase in number of cases" not only indicate the inadequacy of the conventional criteria for the recent cases but also show that the gastritis-like malignancy is detectable. New additional endoscopic criteria for the gastritis-like malignancy, for example, irregular margin of the shallow mucosal depression, disproportion of the mucosal granularity, irregularity on the erythematous change and discoloration are essential in order to detect much more cases with less malignant appearance.

Aged↗
PubMed1984

The role of the biopsy in diagnosis of early gastric cancer.

In order to determine the reliability of endoscopic biopsy in diagnosis of early gastric cancer, and to clarify the problems with biopsies, preoperative endoscopic biopsies from 771 early gastric cancer cases were reviewed and analyzed clinicopathologically in comparison with surgically resected specimens. The 771 cancers were surgically resected at the National Cancer Center Hospital during the period from 1972 to 1982. Definite histological diagnosis was obtained in 87.4% of the carcinomas at the initial biopsies. Repeated biopsy raised the percentage of correct definite diagnoses to 96.1%. False-negative (including suspicion of cancer) diagnosis was most frequent in the case of depressed lesions (50 lesions). Half of the false negatives were found to be due to sampling errors by the endoscopists. The other half of these 50 lesions were diagnosed as "suspicious of malignancy" because of the histological difficulty in differentiating early gastric cancer from regenerative atypia with intestinal metaplasia, or because there was not enough information, or for the other reasons. Most of the 31 false-negative diagnoses at the initial biopsy from elevated lesions were reported as adenoma (group III) or suspicious of carcinoma (group IV), indicating that differential diagnosis between well-differentiated adenocarcinoma and adenoma is very difficult. The result of the present study suggests that repeated biopsy from correct sites and discussion of the lesions between clinicians and pathologists are very important.

Biopsy↗
PubMed1984

Endoscopic treatment of early gastric cancer: polypectomy and laser treatment.

With the tremendous development of gastroenterological endoscopy, it has become possible to treat some types of early gastric cancer by endoscopy. There are two principal methods for this purpose, endoscopic polypectomy using a high frequency electric current and laser endoscopy. We developed the technic and instruments of endoscopic polypectomy, in 1972. Since then, we have experienced 358 cases of gastric polypoid lesions treated by endoscopic polypectomy. Nineteen patients with the elevated type of early gastric cancer were treated by endoscopic polypectomy. Seven patients were operated on after polypectomy and 12 were followed without surgery. Out of the 12 patients, nine are alive after more than five years. On the other hand, we started research to apply lasers for treating early gastric cancer in 1978. Since then, 18 patients have been treated by laser endoscopy, with Nd-YAG laser, argon dye laser or a combination of both lasers. We have established criteria for these treatments for early gastric cancer.

Aged↗