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T Amano

Publications and source records attributed to T Amano.

At least 253 records · Page 14Linked to original sources
PubMed1991

[Enhanced effect of intraperitoneal administration of CDDP combined with caffeine against peritoneal metastasis].

The enhanced effect of CDDP combined with caffeine against P-388 leukemia was investigated. No synergistic effect was shown after one hour simultaneous treatment with CDDP and caffeine. But the growth inhibition was enhanced by the addition of caffeine after one hour treatment with CDDP. It is suggested that caffeine inhibits DNA repair by the reduction of CDDP-induced elongation of G2 + M phase. The increase in life span of mice after ip transplantation was observed by frequent ip injections of caffeine after CDDP injection. It is suggested that the effect of intraperitoneal administration of CDDP against peritoneal metastasis is enhanced by combination with caffeine.

Animals↗
PubMed1991

[Significance of blood vessel invasion in gastric carcinoma--prediction of liver metastases from the blood vessel invasion in the primary tumors].

This study was conducted to elucidate the factors related with liver metastases, to clarify the significance of blood vessel invasion and then to predict liver metastases from these findings. Patients examined were 102 cases which underwent gastrectomy and were followed-up for more than 5 years or until death at our department. Two new staining methods were applied in this study; Victoria blue + hematoxylin eosin double staining for elastic fiber and Factor VIII related antigen for vascular endothelium. Significant differences in qualitative frequency of blood vessel invasion, the number of lymph node metastases, and the depth of invasion were found in those patients with liver metastases, as compared with 5 year survivors. Quantitative analysis of blood vessel invasion revealed significant importance of blood vessel invasions in the submucosa, in the forms of complete thrombus, wall invasion and partial thrombus, in the diameters of 0.01-0.1 mm and 0.1-1.0 mm. Applying discrimination coefficients of linear discrimination analysis, prediction of liver metastases was possible with 81.8% sensitivity, 85.3% specificity, and 83.6% accuracy. Liver metastases can be predicted from the qualitative and quantitative analyses of blood vessel invasion in the primary tumors by elastic fiber staining.

Gastric Mucosa↗
PubMed1991

[Catecholamine fluorescent, acetylcholinesterase positive and peptide immunoreactive nerve fibers in the rat hepatic portal system].

Innervation of rat hepatic portal system consisting of stem (portal vein) and peripheral portions (superior mesenteric vein, inferior mesenteric vein, splenogastric vein) was investigated by catecholamine fluorescence, acetylcholinesterase and immunohistochemical methods. Catecholamine fluorescent and Neuropeptide Y (NPY) immunoreactive (ir) nerve fibers were distributed throughout the hepatic portal system. Greater density was demonstrated in the peripheral portions. Catecholamine fluorescent and NPY ir nerve fibers formed ground plexus around the hepatic portal system. Acetylcholinesterase positive and vasoactive intestinal polypeptide-ir nerve fibers were sparsely distributed and no significant difference in density was noticed in the stem and the peripheral portions. Density of substance P ir, neurokinin A ir and calcitonin gene-related peptide ir nerve fibers was greater in the peripheral than the stem portion. All these fibers reticular showed pattern.

Acetylcholinesterase↗
PubMed1990

Normal pressure hydrocephalus associated with cauda equina neurinoma.

A 65-year-old woman with normal pressure hydrocephalus experienced improved gait and hydrocephalus following surgical resection of a cauda equina neurinoma. Fibrinogen, detected in the cerebrospinal fluid, may be involved in the pathophysiological process of normal pressure hydrocephalus.

Aged↗
PubMed1990

Distribution and ontogeny of chromogranin A and tyrosine hydroxylase in the carotid body and glomus cells located in the wall of the common carotid artery and its branches in the chicken.

Development and distribution of chromogranin A and tyrosine hydroxylase in the carotid body and glomus cells located in and around arteries were examined in chickens at various developmental stages by an immunohistochemical staining. In 9-day-old embryos, numerous cells immunoreactive for tyrosine hydroxylase were already detected in the connective tissue surrounding the carotid body. Some of these cells also showed immunoreactivity for chromogranin A. At 10 days of incubation, a few cells immunoreactive for tyrosine hydroxylase and chromogranin A were detected within the carotid body parenchyma. At 12 days of incubation, almost all glomus cells of the carotid body were intensely immunoreactive for these substances. Furthermore, numerous tyrosine hydroxylase- and chromogranin A-immunoreactive cells were observed in the wall of the common carotid artery, along the whole length of the carotid body artery, and around the roots of the inferior thyroid artery, the ascending esophageal artery and the esophagotracheobronchial artery; the cells already exhibited adult pattern of distribution at this stage of development. Thereafter, glomus cells immunoreactive for both substances gradually increased in number and in intensity of immunoreactivity with age, although the cells located in the wall of the common carotid artery lost immunoreactivity for tyrosine hydroxylase after hatching.

Animals↗
PubMed1990

A combined therapy of hyperthermia and tumor necrosis factor for nude mice bearing KK-47 bladder cancer.

A combined therapy of hyperthermia (43.5 C) and tumor necrosis factor (10(3) and 10(4) units) for the treatment of experimental bladder carcinoma KK-47 in athymic mice was studied. Briefly, mice were injected subcutaneously with 10(7) disaggregated cells. When the tumors were 250 mm3 in size, tumor necrosis factor was administered, either intravenously or by intratumor injection. Intravenous injection was 10(3) to 10(4) units tumor necrosis factor in the tail vein and intratumor was 10(3) to 10(4) units injected directly into the center of the tumor. Immediately following injection, the tumor bearing leg was placed in a 43.5 C water bath for 20 minutes. Tumor size was monitored once a week for seven weeks and the animals were divided into control, hyperthermia alone, tumor necrosis factor alone and combined therapy. Results of the study showed no significant difference in 10(3) units of tumor necrosis factor intravenously versus control but a significant regression in hyperthermia alone. Anti-tumor effects significantly increased in hyperthermia plus 10(3) units tumor necrosis factor versus hyperthermia alone. Similar results were seen with 10(4) units tumor necrosis factor intravenously though in the combination group of hyperthermia and tumor necrosis factor, eight mice of eight died one to three days following treatment. In those receiving intratumor injections, there was no difference between tumor necrosis factor or control. Tumor necrosis factor with hyperthermia had the approximate same characteristics as hyperthermia alone and therefore there was no synergistic finding. These results reflect on the suggestion that the combination therapy of hyperthermia and systemic administration of the proper dosage of tumor necrosis factor may produce synergistic anti-cancer effects in bladder cancer patients.

Animals↗
PubMed1990

Aberrant expression of immunoglobulin light chain isotype in B lymphocytes from patients with monoclonal gammopathies: isotypic discordance and clonal B-cell excess.

A study was made of 29 patients with monoclonal gammopathies to detect aberrations in immunoglobulin (Ig) light chain isotype expression in lymphocytes at various levels of B-cell differentiation, namely, circulating surface Ig positive (SIg+) cells, Ig-secreting cells (plaque forming cells, PFC) and mitogen-induced PFC. By using kappa-lambda analysis, two major phenotypes of aberrant Ig light chain isotype expression were found in circulating B cells at these three levels of differentiation: an absolute increase in B cells bearing the same Ig light chain isotype as that of monoclonal protein (clonal B-cell excess), and a relative decrease in those B cells (isotypic discordance). Isotypic discordance (ID) was found to be essentially negative in patients with monoclonal gammopathy of undetermined significance (MGUS) provided that they were in a stable condition. In myeloma patients, ID was found only in stage I, except for a remission case of stage III (4/7 in stage I, 0/8 in stage II, and 1/6 in stage III). ID was not restricted to a circulating SIg+ cell level but was also demonstrable at a spontaneous or pokeweed mitogen-induced PFC level. However, ID was negative at a PFC level induced by Staphylococcus aureus Cowan I. Clonal B-cell excess (CE) was frequently found in patients with active myeloma but not in stable patients (0/8 in MGUS, 1/7 in stage I, 8/8 in stage II, and 4/6 in stage III). CE was positive not only at a circulating SIg+ cell level but also at a circulating PFC level. Furthermore, patients with CE at a PFC level were found to have a higher proliferating capacity, defined as a percentage labelling index of marrow myeloma cells, than those without CE at a PFC level (P less than 0.02). ID and CE can therefore be considered as useful markers for discriminating between MGUS and myeloma, evaluating the clinical stability and predicting the clinical course.

Antibody-Producing Cells↗
PubMed1990

Measurement of leukotriene B4 in arterial blood of asthmatic patients during wheezing attacks.

To investigate whether leukotriene B4 is present in the arterial blood of asthmatic patients during wheezing attacks, 20 ml of arterial blood was drawn from the inguinal artery of five patients. Leukotriene B4 was detected in all five individuals, and its identity was confirmed by a combination of high pressure liquid chromatography and radioimmunoassay techniques. The concentration of leukotriene B4 was 48.34 +/- 16.27 pg ml-1 (mean value +/- SE). However, in five control subjects the leukotriene B4 concentration was found to be 9.43 +/- 5.44 pg ml-1. Thus there was a significant difference between the two groups (P less than 0.05). These results suggest that leukotriene B4 may be important in elucidation of the pathogenesis of bronchial asthma.

Adult↗
PubMed1990

Reduced reproductive efficiency in mice with schistosomiasis mansoni and in uninfected pregnant mice injected with antibodies against Schistosoma mansoni soluble egg antigens.

Female CBA/J mice were infected with approximately 15 cercariae of Schistosoma mansoni and mated with normal syngeneic males 7 weeks later. Uninfected mice were bred in parallel, and both groups were subsequently bred several more times. Pregnancies were documented by formation of vaginal plugs, and daily records were kept concerning the status of the pregnancies, delivery, and offspring. One hundred thirty-two pregnancies in uninfected mice resulted in 101 (77%) viable litters. In contrast, 133 pregnancies in mice infected with S. mansoni lead to 45 (34%) viable litters. The decreased number of viable litters born or raised by infected mothers resulted from maternal death during pregnancy (5%), spontaneous abortion (20%), and infanticide (42%). Observations of multiparous infected mice indicated that this reduced rate of production of viable, surviving offspring was not different in subsequent pregnancies nor influenced by the duration of the infection. At 2 weeks of age, offspring of infected mice weighed significantly less than offspring of equal-sized litters from uninfected mice, but this weight differential was not sustained beyond 2 weeks of age. Subsequent studies compared the effects on uninfected pregnant mice of injections of antibodies against S. mansoni soluble egg antigens (immunoaffinity-purified from sera of mice with 16 week S. mansoni infections) vs. normal mouse immunoglobulin. After repeated injections of these antibodies during multiple pregnancies, lowered reproductive efficiencies (37%) were observed as compared to parallel studies of pregnant mice injected with normal mouse immunoglobulin (67%).

Animals↗
PubMed1990

Egg signals for triggering the acrosome reaction in starfish spermatozoa.

Upon encountering the jelly coat of an egg, starfish spermatozoa undergo the acrosome reaction. To induce the acrosome reaction, 3 jelly components act in concert on the spermatozoa: a sulphated glycoprotein named acrosome reaction-inducing substance (ARIS), a group of steroidal saponins named Co-ARIS, and an oligopeptide presumably having an ability to increase the intracellular pH of the spermatozoon. All three are required to mimic the full ability of jelly coat to induce the acrosome reaction instantaneously. A combination of ARIS and Co-ARIS is enough for induction in normal sea water, although its action is almost 2 min slower than the jelly. ARIS can induce the acrosome reaction by itself in high Ca2+ or high pH sea water. When spermatozoa meet the jelly coat, the acrosome reaction is eventually induced because ARIS and Co-ARIS co-operatively increase the intracellular Ca2+ by stimulating verapamil- and maitotoxin-sensitive Ca2+ channels and the oligopeptide increases the intracellular pH by stimulating Na+/H+ exchange systems.

Acrosome↗
PubMed1989

The behavior of 99mTc-hexamethylpropyleneamineoxime (99mTc-HMPAO) in blood and brain.

99mTc-hexamethylpropyleneamineoxime (99mTc-HMPAO) is a reagent for scanning cerebral blood flow. We investigated how 99mTc-HMPAO changed in the blood and brain. The 99mTc-HMPAO, which was prepared by adding of 99mTcO4- to HMPAO and Sn(II), consisted of primary and secondary complexes, reduced hydrolyzed 99mTc, and 99mTc-pertechnetate. The percentage of the primary complex in 99mTc-HMPAO decreased with time after preparation. The primary complex converted to the secondary one very rapidly in the presence of plasma. When 99mTc-HMPAO was injected into patients, 99mTc activity was immediately partitioned in the plasma fraction, with approximately 60% in whole blood. In plasma, 99mTc was found to be associated with proteins such as albumin and globulin. 99mTc trapped in red cells was not washed out with either plasma or saline. Biodistribution studies showed that the less lipophilic compounds of 99mTc-HMPAO could not pass through the blood brain barrier (BBB), and therefore did not accumulate in the brain. The results of gel chromatography and equilibrium dialysis indicated that no specific 99mTc binding protein was present in the brain. Considering the instability of 99mTc-HMPAO in vivo, we proposed that the speed at which the primary complex converted to the less lipophilic compounds was important in allowing 99mTc-HMPAO to pass through the BBB and to be fixed in the brain.

Animals↗
PubMed1989

Effects of a selective inhibitor of cyclic AMP phosphodiesterase on the pial microcirculation in feline cerebral ischemia.

We evaluated the effects of cilostazol, a selective inhibitor of cyclic adenosine monophosphate phosphodiesterase, on the pial vessels of adult cats subjected to endothelial damage followed by middle cerebral artery occlusion. Six cats were treated with cilostazol and four with 30% N,N-dimethylformamide in 70% saline (solvent). The brain surface was irradiated with ultraviolet rays through a cranial window for 3 minutes to selectively damage the endothelium of the pial vessels in both groups. Beginning 32 minutes after termination of the irradiation, the middle cerebral artery was occluded for 30 minutes. Thirty minutes before occlusion, intravenous infusion of 30 micrograms/kg/min cilostazol or 0.1 ml/kg/min solvent was begun and continued until the end of the study. Before occlusion, the infusion of cilostazol induced a significant (p less than 0.05) dilatation while the infusion of solvent produced no significant changes in the diameter of the pial arteries. The pial veins of solvent-treated cats showed significant (p less than 0.05) constriction during occlusion, whereas cilostazol-treated cats exhibited only mild constriction of the pial veins. The formation of platelet thrombi after occlusion was significantly (p less than 0.05) inhibited in the pial veins of cilostazol-treated compared with solvent-treated cats. Similarly, the microcirculation of the pial veins was effectively restored after reopening of the middle cerebral artery in cilostazol-treated compared with solvent-treated cats. Our data suggest that cilostazol is an effective antithrombotic agent as well as a potent vasodilator acting on vascular smooth muscle.

Animals↗
PubMed1989

Evidence for transuterine migration of embryos in the domestic cat.

A total of 169 pregnant cats presented for ovariohysterectomy were examined for the number of corpora lutea (CL) and the number of fetuses per uterine horn. The implantation rate and the frequency of occurrence of transuterine migration of embryos were calculated. The average number of CL was 5.6 +/- 1.9 (mean +/- SD; range, 2-11), the average number of fetuses was 4.5 +/- 1.4 (range, 1-8) and the average implantation rate was 84 +/- 20%. Transuterine migration occurred in 69/169 cats (40.8%). In animals with a 100% implantation rate, transuterine migration occurred in 50/84 cats (59.5%). The number of embryos that migrated ranged from 1-3 per animal and embryos moved from the uterine horn ipsilateral to the ovary with the larger number of CL in 66/69 cats (95.7%). As a result of transuterine migration, the difference in the number of fetuses between uterine horns as compared with the difference in the number of CL between ovaries was smaller in 54 casts (78.3%), unchanged in 8 cats (11.6%) and larger in 7 cats (10.1%). These results indicate that cats tend to equalize the number of fetuses between uterine horns by transuterine migration of embryos.

Animals↗
PubMed1989

[Randomized controlled study on adjuvant immunochemotherapy with PSK in curatively resected colorectal cancer. The Cooperative Study Group of Surgical Adjuvant Immunochemotherapy for Cancer of Colon and Rectum].

To evaluate of adjuvant immunochemotherapy with PSK in curatively resected colorectal cancer, randomized controlled study by 35 institutions in Kanagawa prefecture was conducted. From March 1985 till February 1987, 462 patients were assigned one of two different regimens. 448 patients (97.0%) of them satisfied the eligibility criteria. Control group received mitomycin C intravenously on the day and the day after the operations respectively followed by 5-FU orally over for 6 months. PSK group received in addition to mitomycin C and 5-FU as in control group, PSK orally for over 3 years. By February 1989, follow up studies of the patients after their operations had been carried out for two years to four years. The disease free curve and the survival curve of PSK group were higher than those of control group, differences between the two groups were statistically significant (Disease free curve: P = 0.0096, survival curve: p = 0.0391). From these results, adjuvant immunochemotherapy with PSK was considered beneficial for curatively resected colorectal cancer.

Adjuvants, Immunologic↗
PubMed1989

[Complement-mediated solubilization of immune complexes in immune complex nephritis].

In order to examine the ability of complement to solubilize the immune complexes (IC) in vivo, we made acute or chronic serum sickness nephritis in 10 rabbits or 12 rats with injection of BSA as antigen (Ag). Animals were divided into two groups. The 500 mu or 50 mu/week of cobra venom factor (CVF) for rabbits or rats was administered intraperitoneally in one group of animals to reduce the serum complement levels and complement-mediated solubilization of immune complex. On the other hand, the 2 ml or 0.2 ml/week of turpentine oil (TO) was injected intramuscularly in another group of animals to elevate the serum complement levels. The renal biopsy was performed with weekly intervals in each animals, and the specimens were stained for antigen (BSA), antibody (IgG) and C3 by immunofluorescence techniques. The result in this experiments showed the significant difference between TO-, and CVF-treated animals in the degree of disappearance of IC in the kidney lesions. The undetectable amount of IC (especially BSA) was remained in the renal tissue of TO-treated animals. This fact indicated that complement might act to solubilize the IC deposited in the tissue in vivo also.

Animals↗