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T Oda

Publications and source records attributed to T Oda.

At least 397 records · Page 22Linked to original sources
PubMed1992

Immunohistochemical and ultrastructural examination of histiocytosis X cells in pulmonary eosinophilic granuloma.

We describe histological, immunohistochemical, and ultrastructural findings in pulmonary eosinophilic granuloma (PEG) from three patients. The specimens were taken by open-lung biopsy. The lesions of the lung were composed of histiocytic cells, macrophages and eosinophils. The histiocytic cells reacted positively with anti-S-100 protein antibody. The histiocytic cells had various types of Birbeck granules in the cytoplasm. The histiocytic cells were histiocytosis X (HX) cells considered to be derived from Langerhans cells. Sporadic mitosis of HX cells was observed. Some HX cells had migrated from the lesions into the alveolar spaces through the alveolar cell layers. In the lesions of PEG, HX cells have self-reproduction and migration capability.

Adolescent↗
PubMed1992

Nosocomial meningitis due to Campylobacter fetus subspecies fetus in a neonatal intensive care unit.

We experienced a nosocomial outbreak of Campylobacter fetus subspecies fetus (C. fetus) meningitis in a neonatal intensive care unit. A cluster of three infants developed meningitis approximately 1-1.5 months after the index patient was admitted. Two asymptomatic intestinal carriers of C. fetus were detected during the outbreak. Our experience indicates that C. fetus can cause nosocomial meningitis in neonates, and asymptomatic carriers may play a role in the transmission of the organism.

Campylobacter Infections↗
PubMed1992

[A case of pneumonia due to Mycoplasma pneumoniae accompanying high adenosine deaminase activity in pleural effusion].

We experienced a 5-year-old male case of Mycoplasma pneumoniae pneumonia accompanying Adenosine Deaminase (ADA) activity in pleural effusion. Chest roentgenograms revealed the infiltration in the left upper lung field and the left pleural effusion. In serum, the M. pneumoniae CF titer increased to 1:512. The pleural effusion was yellowish in color, with a specific gravity of 1.030, protein 3.7 g/dl, glucose 101 g/dl, and ADA 50 IU/l. Pleural effusion accompanying M. pneumoniae pneumonia is rare, and the high ADA activity in this case has been reported only in one other case. This is a report of a high activity of ADA in the pleural fluid by M. pneumoniae pneumonia.

Adenosine Deaminase↗
PubMed1992

Possible involvement of lipoxygenase products in human corpora lutea.

The present study was undertaken to determine the ability of cultured luteal cells from human corpora lutea to secrete progesterone (P4) and prostaglandins (PGs), and to assess the effects of the products of the lipoxygenase pathway on luteal P4 production. Luteal cells responded to human chorionic gonadotropin (hCG) with a significant increase (2- to 7-fold) in P4 production. Arachidonic acid significantly stimulated PGE2 synthesis by luteal cells in a dose-dependent manner. Both basal PGE2 production and the responsiveness to arachidonic acid were maintained for 8 days. In contrast, both PGF2 alpha and 6-keto-PGF1 alpha production abruptly declined as the culture proceeded. However, the addition of hCG did not further stimulate the accumulation of the 3 PGs assayed. In the subsequent experiment, 5-hydroxyeicosatetraenoic acid (5-HETE) and the reaction products of soybean lipoxidase of arachidonic acid (AA-LIP) were utilized for evaluating the involvement of the lipoxygenase pathway in luteolysis. The addition of 5-HETE dose-dependently inhibited P4 production by the cultured luteal cells. Although treatment with either arachidonic acid or lipoxidase alone had no effect on P4 production, AA-LIP significantly reduced P4 production in the presence or absence of hCG. These results suggest that the products of the lipoxygenase as well as of the cyclo-oxygenase pathway may be important in regulating the life span and function of human corpora lutea.

Adult↗
PubMed1992

Role of corpus luteum function in embryo implantation.

The present study was undertaken to evaluate the role of corpus luteum function in the implantation process of cryopreserved embryos. Six patients with tubal infertility were studied, with a total of 27 fresh embryos being replaced following controlled ovarian hyperstimulation and in vitro fertilization. These embryo transfers failed to produce pregnancy. From the patients, 22 supernumerary embryos were cryopreserved and 10 viable frozen-thawed embryos were transferred in a subsequent natural cycle, resulting in 2 pregnancies. In 1 of the pregnancies, the serum concentrations of estradiol (E2) and progesterone (P4) in the midluteal phase were 29 pg/ml and 5.6 ng/ml, respectively. These values were considered to be below the physiological range. These data suggest that a pregnancy can be achieved in spite of low circulating E2 and P4 levels during the luteal phase, which are generally indicative of the luteal phase defect.

Adult↗
PubMed1992

Nephrotoxicity of germanium compounds: report of a case and review of the literature.

A 55-year-old woman was admitted to our hospital, complaining of general malaise, muscular weakness, anorexia and weight loss. She had a history of ingesting of a certain germanium (Ge) compound over the preceding 19 months, with a total dose of 47 g as Ge element. She was found to have renal failure (blood urea nitrogen, 44 mg/dl; serum creatinine, 2.6 mg/dl) without abnormal findings in urinalysis, and muscular and nervous damage. Initially, polymyositis was diagnosed and prednisolone administered. However, no improvement was seen, and neuromuscular symptoms and signs steadily worsened, ending in death. Microscopic study of the kidney showed that lipofuscin granules increased in the cells of the thick ascending limb of Henle's loop to the distal convoluted tubule accompanying mild tubular atrophy and that some of the tubules of these segments had vacuolar degeneration or desquamation. No apparent glomerular and vascular changes were observed. High Ge content was found in serum, urine and various tissues, e.g., spleen, liver, kidney, adrenal gland and myocardium, while in controls Ge could not be detected in sera, urine or tissues. We also review case reports about Ge toxicity, and discuss the pathogenesis of renal failure induced by Ge compounds.

Acute Kidney Injury↗
PubMed1992

Noncariogenicity of erythritol as a substrate.

Erythritol is a sugar alcohol produced by Aureobasidium sp. from glucose. It is 75-80% as sweet as sucrose and is also nonhygroscopic. The aim of this study was to evaluate this sugar substitute from a cariological point of view. Erythritol was neither utilized as a substrate for the lactic acid production nor for plaque formation of mutans streptococci (serotypes a-h) and certain oral microorganisms. It was not utilized for water-insoluble glucan synthesis or cellular adherence by glucosyltransferase from Streptococcus mutans PS-14 (c) and Streptococcus sobrinus 6715 (g). Finally, a significantly lower caries score (3.1 +/- 0.5; mean +/- SEM) was observed in specific pathogen-free rats infected with S. sobrinus 6715 and fed with a diet containing 26% erythritol, as compared to control rats fed with a diet containing 26% sucrose (60.5 +/- 2.0). Also, rats provided a diet containing 56% erythritol chocolate (23.8% erythritol) and challenged with S. mutans PS-14 exhibited a significantly lower caries score (6.7 +/- 0.8) compared to the sucrose chocolate group (82.8 +/- 2.8). The main conclusion from this study is therefore that erythritol is a promising sugar substitute from a cariological point of view.

Actinomyces↗
PubMed1992

Stimulatory role of cyclic adenosine monophosphate as a mediator of meiotic resumption in rabbit oocytes.

The present study was undertaken to assess the role of alterations of intraoocyte cAMP concentrations in the meiotic maturation of isolated and follicle-enclosed oocytes. In isolated oocyte culture, the intracellular cAMP content of denuded oocytes declined within 15 min of incubation, whereas the cAMP content of cumulus-enclosed oocytes did not change substantially for 1.5 h of incubation, and then declined abruptly. Commitment to meiotic maturation was preceded by reduced concentrations of intraoocyte cAMP. Forskolin inhibited the spontaneous maturation of cumulus-enclosed oocytes in a dose-dependent manner. However, this inhibition was attenuated as the duration of incubation increased. Forskolin significantly stimulated the intracellular cAMP content of denuded and cumulus-enclosed oocytes, but intraoocyte cAMP returned to pretreatment values within 4 h. The decline in intraoocyte cAMP was followed by the meiotic maturation of isolated oocytes. In in vitro perfused rabbit ovaries, exposure to forskolin at 10(-4) M, as well as to 50 IU human CG, accelerated the meiotic maturation of follicle-enclosed oocytes. The intraoocyte cAMP content increased significantly within 30 min and reached its maximum 2 h following exposure to forskolin. Thereafter, cAMP decreased abruptly and returned to pretreatment levels by 6 h. These alterations of intraoocyte cAMP contents following exposure to forskolin paralleled those observed in human CG-treated ovaries. The decline in cAMP content of follicle-enclosed oocytes was followed by their meiotic maturation. In conclusion, the sustained elevation of intraoocyte cAMP levels inhibits the initiation of meiotic maturation in isolated and follicle-enclosed oocytes. Within the follicle, resumption of meiosis is triggered via a transient increase in intraoocyte cAMP, but commitment to meiosis must await the decline of intraoocyte cAMP.

Animals↗
PubMed1992

Effect of estradiol and ethynylestradiol on microtubule distribution in Chinese hamster V79 cells.

The effects of estradiol (E2) and ethynylestradiol (EE2) on the chromosome number and cellular microtubule architecture of Chinese hamster V79 cells were studied using fluorescent anti-tubulin antibody. Treatment with 20 microM E2 for 48 h induced only a small amount of tetraploid cells, but the normal microtubule network was disrupted completely by only 3 h of treatment. This data reveals that E2 has higher microtubule-disruptive activity than diethylstilbestrol in V79 cells.

Animals↗
PubMed1992

Effects of 3,3'-dihydroxy-alpha,beta-diethylstilbene and 3,3',4,5'-tetrahydroxystilbene on microtubule assembly in vitro, aneuploidy induction, and cellular microtubule and actin networks.

We examined the inhibitory activities of 3,3'-dihydroxy-alpha,beta-diethylstilbene (DDS) and 3,3',4,5'-tetrahydroxystilbene (THS) on microtubule assembly in vitro and their effects on chromosome number and cellular microtubule networks in Chinese hamster V79 cells. DDS showed half the inhibitory activity of diethylstilbestrol (DES) on microtubule assembly in vitro, while THS had none of the inhibitory activity. DDS induced tetraploid at 30 microM, whereas THS was found to be inactive. Furthermore, DDS disturbed cellular microtubule networks at 100 microM. We also examined the effects of DES, DDS and THS on cellular actin networks in mouse BALB 3T3 cells. DES induced a change of actin stress fiber distribution and THS had similar activity, while DDS showed no activity.

Actins↗
PubMed1992

Effects of (+)-, (-)- and (+/-)-indenestrols A and B on microtubule polymerization.

Indenestrol A (IA) is a metabolite of diethylstilbestrol (DES), and indenestrol B (IB) is an analog of IA. IA was simply obtained from E,E-dienestrol in the presence of dilute sulfuric acid, and a mixture of IA and IB was formed by thermal cyclization of E,E-dienestrol. In order to elucidate the effects of optically active IA and IB on microtubule assembly, the IA and IB enantiomers were separated to greater than 99% purity by high-pressure liquid chromatography using a chiral column. The di(4-bromobenzoate) of (-)-IB was analyzed by X-ray crystallography and its absolute structure was determined as C(3)-S. The (+)-, (-)-, and (+/-)-indenestrols A and B were shown to be inhibitors of microtubule assembly in vitro using microtubule proteins from porcine brain. (+/-)-IB is more active than (+/-)-IA, and the order of inhibitory activity of the enantiomers on microtubule assembly was (+)-IB greater than (+)-IA greater than (-)-IA greater than (-)-IB.

Animals↗
PubMed1992

Effect of the combination of anticoagulant and thromboxane synthetase inhibitor (Y-20811) or receptor blockade (S-1452) on preventing thrombotic cyclic coronary flow reduction in dogs with coronary stenosis.

We examined the hypothesis that combined actions of anticoagulant (heparin) and Y-20811, thromboxane A2 synthetase inhibitor (TXSI), or S-1452, receptor blockade (TXRB), can provide better antithrombotic protection than TXSI or TXRB alone. In 20 of 33 dogs instrumented, placement of a critical stenosis at a focus of coronary vascular injury initiated a reproducible cyclic coronary flow reduction (CCFR). TXSI (1 mg/kg, IV) perfectly inhibited CCFR in 6 of 10 dogs (60%), and was associated with a significant decrease in 11-dehydro-TXB2 (85 +/- 8% of control; p < 0.05) and an increase in 6-keto-PGF1 alpha (155 +/- 38%; p < 0.05) in coronary sinus blood samples. In the remaining 4 dogs, additional administration of heparin (2000 IU) completely abolished CCFR. On the other hand, TXRB (1 mg/kg, IV) perfectly inhibited CCFR in 7 of 10 dogs (70%), and was accompanied by a significant increase in 6-keto-PGF1 alpha (214 +/- 65%; p < 0.05) and unchanged TXB2 level. In the remaining 3 dogs, additional administration of heparin (2000 IU) completely abolished CCFR. Thus, the combination of anticoagulant and TXSI or TXRB were more effective than TXSI or TXRB alone in abolishing thrombotic CCFR, suggesting that the combination might be effective for treating patients with impending myocardial infarction.

Animals↗
PubMed1992

Possible involvement of leukotrienes in human luteal function.

The present study was undertaken to assess the ability of human corpora lutea to produce leukotriene B4 (LTB4). The maximum capacity of luteal cells to secrete progesterone was attained on day 4, and both the basal production and the responsiveness to hCG decreased thereafter. In contrast, the production of LTB4 by cultured luteal cells was significantly reduced on day 4, but increased thereafter. The basal concentration of LTB4 produced by luteal cells varied from 75 to 590 pg/10(5) cells/2 days. LTB4 production appeared to decrease concomitantly with increased-progesterone production in cultured luteal cells. Exposure to hCG decreased significantly LTB4 production by cultured luteal cells on day 4. An inhibitor of the lipoxygenase pathway, nordihydroguaiaretic acid (NDGA), inhibited LTB4 production in a dose-dependent manner. However, NDGA did not affect basal progesterone production by the cultured luteal cells. A significant inverse relationship existed between the accumulation rates of progesterone and LTB4 in the luteal cells. Furthermore, the addition of LTB4 inhibited progesterone production in a dose-dependent manner in both the presence and absence of hCG. In conclusion, LTB4 could be synthesized by human corpora lutea in vitro, and correlated inversely with the secretion rates of progesterone. These data suggest that LTB4 produced locally in the corpus luteum may be an important regulator in human luteal regression.

Adult↗
PubMed1992

Induction of meiotic maturation of follicle-enclosed oocytes of rabbits by a transient increase followed by an abrupt decrease in cyclic AMP concentration.

The involvement of cyclic adenosine monophosphate (cAMP) in mammalian oocyte maturation was assessed using cultures of rabbit cumulus-oocyte complexes and perfused rabbit ovaries. Rabbit cumulus-oocyte complexes were cultured in Brackett's medium with or without forskolin at 10(-4), 10(-5) or 10(-6) mol l-1 for 3-6 h. At 3 or 4 h spontaneous meiotic maturation was significantly (P < 0.05) inhibited by forskolin at 10(-4) mol l-1. With prolonged incubation, spontaneous maturation progressed despite exposure to forskolin. In the second experiment ovaries were perfused for 12 h with forskolin (10(-4), 10(-5) or 10(-6) mol l-1) or medium alone. Neither ovulation nor degeneration of follicular oocytes occurred in any perfused ovary. The percentage of follicular oocytes achieving germinal vesicle breakdown was significantly (P < 0.001) increased in response to forskolin in a dose-related manner. In an additional experiment, ovaries were perfused with forskolin at 10(-4) mol l-1. A significant increase in the cAMP content in the follicle was observed within 30 min, but the ability to produce cAMP in response to forskolin decreased as the duration of perfusion was increased. Intraoocyte cAMP increased significantly within 30 min and reached its maximum 2 h after exposure to forskolin. Thereafter, cAMP levels in the oocytes decreased abruptly. This drop in intraoocyte cAMP concentration was followed by the resumption of meiosis. The alterations of intraoocyte cAMP contents following exposure to hCG in vivo paralleled those observed in the ovaries perfused with forskolin. These data suggest that a transient, but not continuous, increase in cAMP concentration after the gonadotrophin surge may be required to initiate oocyte maturation.

Animals↗
PubMed1992

Comparisons of the bacterial flora in genital regions at non-pregnancy.

In the development of infectious diseases at non-pregnancy and at pregnancy, correlations between bacterial flora in the vagina and portio vaginalis and the ascending infections of those bacteria have recently been discussed. To clarify the cause of those infectious diseases, we studied the localization of microorganisms in genital regions. Patients undergone abdominal total hysterectomy (n = 172) were employed as subjects, and microorganisms isolated from 4 genital regions were studied. In addition, the preventive effect of cefmetazole (CMZ) against postoperative infections was analyzed in 479 cases including the hysterectomy cases mentioned above. The results obtained are summarized as follows: 1. The isolation rate of microorganisms at non-pregnancy, from subjects of 30 to 69 years old, was 65.6% (82/125) in the vagina and portio vaginalis, 52.1% (25/48) in the cervical mucus, 7.3% (9/124) in the uterine cavity and 0% (0/47) in the ovarian surface. 2. Numbers of microorganisms isolated in each region were 99 strains in the vagina and portio vaginalis, 28 in the cervical mucus, 10 in the uterine cavity and none in the ovarian surface. Isolation of aerobic Gram-positive bacteria (60-89.3%) and anaerobic Gram-positive bacteria (7.1-30%) were varied in each region. Lactobacillus spp. (38 strains), Staphylococcus epidermidis (20 strains) and Propionibacterium acnes (10 strains) were isolated from vagina and portio vaginalis, and Lactobacillus spp. (17 strains) were the most often isolated bacteria from the cervical mucus.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

[A case of extra-adrenal pheochromocytoma with frostbite in extremities].

We describe a patient who presented frostbite in extremities in addition to characteristic symptoms, such as severe hypertension, sweating attacks, palpitations and headache. The patient was eventually diagnosed as having single extra-adrenal pheochromocytoma. The frostbite in extremities rapidly resolved after the removal of the tumor as well as other characteristic clinical symptoms. It is speculated that this frostbite might have been induced by severe continuous constriction of peripheral artery and loss of heat by frequent sweating attacks. Regarding cutaneous symptoms in this disease, pallor, acrocyanosis and cold extremities are commonly found. However, it seems that typical frostbite associated with pheochromocytoma has not been reported so far.

Adult↗