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T Hashizume

Publications and source records attributed to T Hashizume.

At least 163 records · Page 9Linked to original sources
PubMed1990

Two cases of pilomatrix carcinoma.

We report two cases of pilomatrix carcinoma. Wide surgical excision, radiation, and chemotherapy were required for the first patient. The tumor eventually revealed the characteristics of a carcinoma, both clinically and histopathologically, as it recurred. In the second case, although the tumor exhibited the histology of pilomatricoma in the central part of the lesion, there were numerous outgrowing irregular nests of basaloid tumor cells with cellular atypia and frequent mitoses; these are the characteristic features of the pilomatrix carcinoma in its early stages.

Adult↗
PubMed1990

[Continuous monitoring of mixed venous oxygen saturation during exercise using fiberoptic pulmonary artery catheter].

We measured the mixed venous oxygen saturation (SvO2) continuously using a fiberoptic thermodilution pulmonary artery catheter to analyze the time course of SvO2 during exercise, and evaluated the relationship between SvO2 and exercise load, SvO2 and cardiac output. Five patients with old myocardial infarction and one healthy man underwent pulmonary arterial catheterization and then performed an incremental steady state exercise test using a supine cycle ergometer. There was a rapid fall in SvO2 43.4 +/- 10.6 seconds after the start of exercise and new steady state were achieved 92.6 +/- 22.5 seconds after changing the exercise load. The value of SvO2 at exercise load 60 watts were 44.7 +/- 9.8% and this value was under the level of lactic acid accumulation. SvO2 correlates well with cardiac output by the thermodilution method in individual patients. We conclude that a fiberoptic thermodilution pulmonary artery catheter was useful to evaluate the dynamic changes of SvO2 during exercise.

Adult↗
PubMed1990

[The DNA ploidy patterns in early gastric cancers as a criterion for surgery].

A study of the ploidy patterns in gastric cancer has been conducted, focusing on 20 cases diagnosed prior to surgery as early stage gastric cancers. The gastric cancer in 10 cases was confined to the submucosa, where as in the other 10, the gastric cancer had invaded the muscle propria. The DNA ploidy patterns were classified as follows: Type D, Type A1 and Type A2. Even with gastric cancers of less than 2 cm, the likelihood that those with Type A1, and Type A2 patterns would spread into the lymph node was high (A1, 43% and A2, 67%), suggesting that careful consideration should be given to limiting the intended surgery. With gastric cancers of the Type D pattern, however, the incidence of a lymph node metastasis was low. These results are felt to be important factors when considering the extent of surgery.

DNA, Neoplasm↗
PubMed1990

Antiulcer effects of 3-[[[2-(3,4-dimethoxyphenyl)ethyl] carbamoyl]methyl]-amino-N-methylbenzamide in experimental gastric and duodenal ulcers.

Effects of 3-[[[2-(3,4-dimethoxyphenyl)ethyl]carbamoyl] methyl]-amino-N-methylbenzamide (DQ-2511), a newly synthesized compound, were evaluated using various types of experimental gastric and duodenal ulcers in rats. Pretreatment with DQ-2511, over the dose range 30-300 mg/kg p.o., resulted in a dose-related inhibition of water-immersion stress-, serotonin-, acetylsalicylic acid (ASA)-, indometacin-, ethanol-, and 2-deoxy-D-glucose(2DG) plus indometacin-induced gastric ulcers as well as cysteamine-induced duodenal ulcers. The antiulcer potencies of DQ-2511 were equal to or greater than those of H2-receptor antagonist cimetidine in these ulcer models except for ASA- and 2DG plus indometacin-induced ulcers. The rate of healing of chronic gastric ulcers induced by acetic acid was significantly accelerated by DQ-2511 (100 and 300 mg/kg p.o.) but not by the same doses of cimetidine. DQ-2511, at doses of 30 mg/kg p.o. and above, produced a significant decrease in gastric acid and pepsin output in pylorus-ligated rats. In anesthetized rats with acute gastric fistulae, 30 mg/kg i.v. of DQ-2511 significantly inhibited gastric acid secretion stimulated by 2DG, whereas it did not affect gastric hyperacidity evoked by either carbachol, histamine or pentagastrin. At effective antiulcer doses, this compound produced a sustained increase in gastric mucosal blood flow in conscious, restrained rats. Based on these observations, DQ-2511 is characterized as a new antiulcer compound with beneficial effects on both gastric aggressive and defensive factors. Furthermore, these results indicate a possible superiority of DQ2511 over cimetidine in regard to its antiulcer potency and spectrum.

Animals↗
PubMed1989

Platelet desensitization by arachidonic acid is associated with the suppression of endoperoxide/thromboxane A2 binding to the membrane receptor.

The inhibitory mechanism of high levels of exogenously added arachidonic acid on activation of washed human platelets was investigated. While low levels of arachidonic acid (5-10 microM) induced aggregation, ATP secretion and increase in cytoplasmic free Ca2+ concentration (first phase of activation), these platelet responses did not occur significantly at high concentrations (30-50 microM). However, much higher concentrations than 80 microM again elicited these responses (second phase). The first phase of platelet activation was inhibited by cyclooxygenase inhibitor, indomethacin, whereas the second one was independent of such treatment. Thromboxane B2 was produced dose-dependently until reaching a plateau at arachidonic acid concentrations higher than 20 microM, irrespective of the lack of aggregation and secretion at high concentrations. After that the amount of free arachidonic acid which remained unmetabolized in platelets gradually increased. High concentrations of arachidonic acid as well as other polyunsaturated fatty acids caused desensitization of platelets in response to U46619, and also depressed the specific [3H]U46619-binding to the receptor as well as other polyunsaturated fatty acids. The amount free arachidonic acid needed in platelets to suppress [3H]U46619 binding corresponded to that needed to inhibit platelet aggregation. Furthermore, arachidonic acid dose-dependently induced fluidization of lipid phase of platelet membranes as detected by 1,6-diphenyl-1,3,5-hexatriene. These results suggest that the inhibition of platelet response by high levels of arachidonic acid can be attributed to interference with endoperoxide/thromboxane A2 binding to the receptor, probably due to perturbation of the membrane lipid phase due to excess amounts of free arachidonic acid remaining in the membranes.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed1989

Purification of cytochrome P-450 from polychlorinated biphenyl-treated crab-eating monkeys: high homology to a form of human cytochrome P-450.

Cytochrome P-450, designated as P-450-MK2, was purified to an electrophoretic homogeneity from polychlorinated biphenyl (PCB)-treated female crab-eating monkeys. P-450-MK2 catalyzed nifedipine and nilvadipine oxidations, at a rate comparable to human P-450-HM1. The N-terminal amino acid sequence of P-450-MK2 was highly homologous to those of P-450-HM1 and NF 25. The antibodies to P-450-HM1 recognized P-450-MK2 and effectively inhibited the activity of testosterone 6 beta-hydroxylase in monkey liver microsomes. These results suggest that a form of cytochrome P-450 corresponding to human P-450-HM1 or P-450NF which belongs to the P450 III gene family is also present in liver microsomes of crab-eating monkeys.

Amino Acid Sequence↗
PubMed1989

Distributional variation of P-450 immunoreactive hepatocytes in human liver disorders.

Implications of P-450 in human hepatic disorders were immunohistochemically examined. We first confirmed that an antibody against P-450-HM1, an isozyme of cytochrome P-450 which was purified from human livers at autopsy, detects only P-450 on immunoblots. In a study of 79 consecutive autopsied livers using the avidin-biotin-peroxidase complex method, the antibody reacted strongly with fetal hepatocytes, the reaction being more intense in the left lobe than in the right lobe. In normal livers, immunoreactivity was confined to centrilobular hepatocytes, decreasing in the periportal zone. Enhanced expression was occasionally found in scattered hepatocytes and in hepatocytes surrounding sublobular veins; this enhancement was related to longterm steroid therapy. No specific induction was observed in patients with toxic hepatitis. In patients with fibrosis, cirrhosis, or regenerative nodules, however, P-450-positive hepatocytes were observed in the periportal and middle zones as well as in the central zone. In contrast, hepatocellular carcinomas were devoid of P-450 immunoreactivity. These results suggest that P-450-HM1, which is abundant in the fetal liver, is reexpressed in regenerating hepatocytes but not in cancers.

Antibody Specificity↗
PubMed1989

Comparison of delayed imaging with Tc-99m PMT and Tc-99m DEIDA for visualization of hepatoma.

Delayed imaging was performed after the intravenous administration of Tc-99m DEIDA and Tc-99m PMT in 18 patients with hepatocellular carcinoma. Using Tc-99m DEIDA imaging, sharp uptake by liver tumors was observed in four patients (22%), but the uptake was similar to that of the surrounding normal liver in eight patients (44%). Using Tc-99m PMT imaging, the uptake by the tumor was notable in ten patients (56%) and normal in two (11%). Tc-99m PMT and Tc-99m DEIDA were both concentrated in hepatocellular carcinomas, but the former showed intense uptakes more frequently, and thus is suggested to be useful in the diagnosis of hepatocellular carcinoma.

Aged↗
PubMed1989

In vitro and in vivo antibacterial activities of BO-1341, a new antipseudomonal cephalosporin.

BO-1341, a new antipseudomonal semisynthetic cephalosporin, was evaluated for in vitro and in vivo antibacterial activities in comparison with ceftazidime, cefotaxime, and cefoperazone. The in vitro activity of BO-1341 was generally superior or comparable to the activities of the reference antibiotics against clinical isolates of the family Enterobacteriaceae. BO-1341 was highly active against Pseudomonas aeruginosa (MIC for 90% of the strains tested, 1.56 micrograms/ml), Pseudomonas maltophilia (MIC for 50% of the strains tested, 1.56 micrograms/ml), and Acinetobacter calcoaceticus (MIC for 90% of the strains tested, 3.13 micrograms/ml). Furthermore, BO-1341 was highly active against P. aeruginosa isolates resistant to the other antibiotics. Of 199 P. aeruginosa isolates tested, only 2 were resistant to BO-1341. These two strains were also resistant to ceftazidime, cefotaxime, and cefoperazone. Haemophilus influenzae, Branhamella catarrhalis, and nonenteric streptococci were also susceptible to BO-1341, but Staphylococcus aureus, Streptococcus faecalis, and Bacteroides fragilis were not susceptible to the compound. The protective efficacy against experimental infections in mice caused by nine strains of gram-negative bacteria, including P. aeruginosa, reflected the potent in vitro activity.

Animals↗
PubMed1989

Conformational characteristics of 4-acetylcytidine found in tRNA.

The conformational characteristics of a modified nucleoside 4-acetylcytidine (ac4C) was analyzed by proton nuclear magnetic resonance spectroscopy. This nucleoside was found to take the C3'-endo form predominantly. The enthalpy difference between the C2'-endo form and the C3'-endo form of the ribose moiety of ac4C was determined and 4-acetylation was found to stabilize the C3'-endo form further by 0.83 kcal.mol-1. This conformational characteristics of ac4C is probably important for the correct codon recognition and the stability of the tertiary structure of tRNA molecule.

Cytidine↗
PubMed1989

[New classification and analysis of lung sounds].

Recently, classification and nomenclature of lung sounds has been changed from assessment based on subjective interpretation to assessment based on objective, measureable criteria related to mechanisms of sound generation. The adventitious sounds was classified to four kinds of principal terms, continuous adventitious sounds (wheezes, rhonchi) and discontinuous adventitious sounds (coarse crackles, fine crackle) at the 1985 International Symposium on Lung Auscultation. Lung sounds in the surgical patients were digitized for the analysis of both the time domain and the frequency domain which had been recorded by tape recorder. Rhonchi, fine crackle and tracheal stenotic sounds were characterized by the analysis of the frequency domain. Lung sound analysis is promising because it is safe, non invasive and may be used for clinical studies in the surgical patients.

Humans↗
PubMed1988

Vinblastine inhibits platelet aggregation by a microtubule-independent mechanism, probably by its perturbing action on the plasma membrane.

Inhibitory mechanism of vinblastine on platelet activation was examined with respect to its effect on disassembly of the microtubule system. Vinblastine at 10 microM concentration caused washed platelets to become sphere with disorganized microtubule system, but did not affect aggregation induced by collagen, arachidonic acid or thrombin. Collagen-induced aggregation was inhibited by 50-100 microM of vinblastine and much higher concentration was required to inhibit arachidonic acid- and thrombin-induced aggregation. When the vinblastine (100 microM)-treated platelets were washed with albumin medium, the impaired aggregability was well recovered in response to collagen. In this case, however, both the vinblastine-induced sphered shape and disappeared microtubule system were not recovered to the normal states. Within the concentration ranges that inhibited collagen-induced aggregation, vinblastine also suppressed reversibly Ca2+ influx and arachidonic acid liberation from membrane phospholipids by phospholipase A2. Conversion of added arachidonic acid to thromboxane A2 was not inhibited even by such concentration. These results suggest that vinblastine interacts non-specifically with the cell membrane to cause reversible inhibition of arachidonic acid liberation by phospholipase A2 and Ca2+ influx and thereby aggregation through physical perturbation of membrane lipid bilayer, independent of the activity to disassemble platelet microtubule system.

Adenosine Triphosphate↗
PubMed1988

Glucagonoma syndrome.

A 53-year-old Japanese man with a skin eruption characteristic of glucagonoma syndrome had had misdiagnoses for 10 years. The plasma glucagon level was not abnormally high on the first admission, and 4 years later the level was elevated as determined by the 30 gm arginine tolerance test. An alpha cell carcinoma detected in the tail of the pancreas was associated with a lymph node metastasis; the skin eruption cleared up 10 days after the partial pancreatectomy with lymphadenectomy. The clinical features of glucagonoma syndrome should be given attention.

Adenoma, Islet Cell↗