Biomedical subjects

Y Hatakeyama

Publications and source records attributed to Y Hatakeyama.

At least 55 records · Page 3Linked to original sources

PubMed1993

[An experimental study evaluating the efficacy of platelet aggregation inhibitory (OKY-046) for hepatic metastasis of VX2 carcinoma].

To investigate whether a platelet aggregation inhibitor (OKY-046) can inhibit VX2 tumor metastasis, VX2 tumor cells (1 x 10(7) cells) were inoculated into the portal vein and OKY-046 (an inhibitor of thromboxane A2 synthesis) was administered continuously at 0.2 mg/kg/hour (group A), and 0.6 mg/kg/hour (group B) into the portal vein from 30 min, before tumor cell inoculation through the following 2 days. In group C, adriamycin (ADM) 1 mg/kg was administered via the portal vein on the next day, 3rd, and 5th day after OKY-046 infusion was completed. Only ADM was administered into the portal vein on the 3rd, 5th and 7th day in group D and immediately and on the 2nd and 4th day after tumor cell inoculation in group E. The numbers of tumor nodules on the whole liver surface at three weeks after tumor inoculation in the control, group A, B, C, D and E were 546 +/- 79, 504.5 +/- 74, 438.8 +/- 59.9, 8 +/- 6.1, 130 +/- 89.7, and 9.5 +/- 5.3, respectively. These results suggest that the inhibitory effect of the tumor growth of OKY-046 depended on inhibition of extravasation of the portally inoculated VX2 tumor cells.

Animals↗

PubMed1992

[Flower bud differentiation and development of opium poppy (Papaver somniferum L.) II. Effects of daylength and temperature].

We investigated the effect of daylength (from 9 to 15 hours) and cultivation temperature (from about 13 to 25 degrees C) on flower bud differentiation of three strains of Papaver somniferum L. cv. Ikkanshu, which have been cultivated in Nayoro (Hokkaido), Tsukuba (Central Honshu) and Nagasaki (Kyushu) for the last a few decades. 1. The experiment on the effect of daylength on flowering revealed that the longer the photoperiod was, the earlier flowering occurred. 2. Flower bud differentiation was observed at temperatures of 20 degrees C or less but never at 25 degrees C, and it was more quickly induced at lower temperatures. Furthermore, we also found that the optimum temperature for flower bud development following differentiation was 20 degrees C. From these findings, we reached the conclusion that this species has thermosensitivity. 3. Flower bud differentiation clearly occurred later in the Nayoro strain than in the Nagasaki strain or the Tsukuba strain. This seems to indicate that the Nayoro strain is a different ecological type from other strains. 4. When we compared the size and dry weight of the capsules, which are known to be closely related to opium yield, the capsules of the Nagasaki and Tsukuba strains were considerably smaller and lighter than those of the Nayoro strain. This is attributable to the fact that flower bud differentiation occurred at an early stage before the achievement of sufficient vegetative growth in the Nagasaki and Tsukuba strains.

Light↗

PubMed1992

[Intrathecal morphine for postoperative pain relief after transvaginal hysterectomy].

We studied the effect of a low-dose intrathecal morphine (0.1 or 0.2 mg) in postoperative pain relief and the incidence of side effects. Two hundred and fifteen patients scheduled for transvaginal hysterectomy were divided into 3 groups according to intrathecal morphine doses: M1 (morphine 0.1 mg N = 75), M2 (morphine 0.2 mg N = 69) and C (control N = 71). A standard mid-line lumbar puncture was performed using a 25-gauze needle in the L3/4 interspace. Preservative-free morphine hydrochloride mixed in hyperbaric tetracaine solution was administered intrathecally. Pain relief was significantly greater for the first 24 hrs in groups M1 and M2 compared with group C. Respiratory depression was not seen in any groups. The incidence of vomiting was about 40% in all groups. We conclude that intrathecal morphine 0.1-0.2 mg is useful for pain relief after transvaginal hysterectomy and accompanies no major side effects.

Adult↗

PubMed1992

[Comparative study of the efficacy of hepatic arterial and portal venous infusion of adriamycin for prevention of liver metastases in rabbit VX2].

To compare the efficacy of hepatic arterial (HA) and portal venous infusion (PV) anticancer drugs in the prevention of the liver metastasis of cancer, the following experimental study was performed. VX2 tumor cells (1 x 10(7) cells) floating in physiological saline were injected into the portal vein of Japanese white rabbit. Adriamycin (ADR) was administered to the liver via HA or PV at 3, 5, 7 (1 mg/kg) days, and immediately, 2, 4 days after tumor inoculation, respectively. The rabbits were sacrificed 3 weeks after tumor inoculation and the total number of liver metastases was counted. Results were as follows: 1) The numbers of metastatic VX2 tumor nodules in HA group were significantly smaller than in PV group (p = 0.05). 2) Starting ADR injection immediately after tumor inoculation enhanced the inhibition of tumor growth. These results suggest that immediate hepatic arterial infusion of anticancer drugs after resection of primary gastrointestinal cancer is most useful to prevent liver metastases.

Animals↗

PubMed1990

[Study of bone metabolism for breast cancer by MD (microdensitometry) method].

Bone is one of the involved organs of distant metastasis in breast cancer. We examined bone metabolism by microdensitometry (MD) method in 94 patients with breast cancer (40 with bone metastasis and 54 without it) and 10 with benign breast diseases. There was no significant difference among the three groups in the background factors of menopausal status and hormone receptors status. MCI, GSmin, sigma GS/D and bone pattern by MD method in breast cancer patients with bone metastasis were significantly lower than those in the other groups. There were slight reverse correlation between sigma GS/D and serum ALP. MCI and sigma GS/D indices corrected by ages were also significantly lower in bone metastasis (p less than 0.01). These indices in most of the patients with bone metastasis gradually decreased as the lesion progressed. The results revealed that microdensitometric analysis of bone metastasis for breast cancer was of use for the diagnosis and evaluation of therapeutic effect in the follow-up study.

Adult↗

PubMed1990

Design of a polyvinyl alcohol hydrogen containing phospholipid as controlled-release vehicle for rectal administration of (+/-)-propranolol HCl.

Polyvinyl alcohol hydrogels which contained phospholipid, egg yolk lecithin or hydrogenated soya lecithin were designed as a transrectal delivery system for propranolol hydrochloride. The hydrogel preparations containing phospholipid were prepared by a low-temperature crystallization method. The release profile of propranolol from hydrogel preparations containing phospholipid complied with Fickian diffusion (Higuchi model). The release of propranolol from the hydrogel preparation decreased with higher contents of phospholipid (approximately 2% w/w). In rats plasma concentrations of propranolol after rectal administration of hydrogel preparations containing phospholipid (1 and 2% w/w) were prolonged compared with those of rats receiving preparations without phospholipid.

Administration, Rectal↗

PubMed1990

[Some aspects of third molars with regard to the development of malocclusions].

Although the orthodontist is constantly aware of the developing third molar and its possible effects on the dentition during and after orthodontic treatment, the relationship between the third molar and the development of malocclusion had not been resolved. To attempt to clarify some of the problems associated with the third molar, an analysis of the factor in fluencing on the dentition and denture frame was performed. In this study, twenty-one adult cases which had no prothodontic correction of the tooth shape and orthodontic treatment with at least three wisdom teeth were used for evaluation of the denture frame structure and occlusion. The case which impacted third molar (M3 impacted group) showed less than 25 degree mandibular plane angle (FH-MP) without exception, while the case which the third molar erupted (M3 erupted group) were able to divide into high angle (more than 30 degree of FH-MP) and low angle (less than 29 degree of FH-MP) groups. The M3 impacted with low angle group and M3 erupted with low angle group showed relatively normal occlusion and favorable denture frame structure, but M3 erupted with high angle group indicated that the denture frame composition was affected by posterior discrepancy especially the steepness of occlusal plane which might be the over eruption of posterior teeth. The M3 erupted with high angle group also included two cases of severe anterior open-bite with skeletal deformity. These findings suggest that the posterior discrepancy due to existence of third molars influence on the dento-facial-skeletal structure and development of malocclusions.

Adult↗

PubMed1989

Administration-route-related differences in the micronucleus test with benzene.

The effect of route of administration on the outcome of the micronucleus test was studied in 2 laboratories by administering the model chemical benzene intraperitoneally (i.p.) and orally (p.o.) to 2 strains of mice: MS/Ae and CD-1. On the basis of results obtained in a small-scale acute toxicity study and in a pilot micronucleus test, full-scale micronucleus tests were performed with a 24-h sampling time at doses of 250, 500, 1000, and 2000 mg/kg i.p. and 500, 1000, 2000, and 4000 mg/kg p.o. In both strains of mice, a higher incidence of micronucleated polychromatic erythrocytes (MNPCEs) was observed after p.o. administration. The ratio of polychromatic erythrocytes (PCEs) to total erythrocytes decreased more markedly at higher doses i.p. in both strains. Thus, benzene induced more micronuclei via the p.o. route, while inhibitory effects on bone marrow cells were stronger after i.p. administration.

Administration, Oral↗

PubMed1989

Human parvovirus (HPV/B19) infection with purpura.

A 33-year-old man complained of purpura (petechial hemorrhage) in chelidons, poples, axillae, and bilateral chest in addition to other symptoms such as lumbago, arthralgia, muscular pain, and fever. On the next day of the onset, human parvovirus (HPV/B19) antigen and HPV/B19 DNA were detected in his serum, and twelve days later IgM antibody to HPV/B19 became detectable. This case supports the relationship between purpura and HPV/B19 infection.

Adult↗

PubMed1989

Antiulcer activities of glycyrrhetinic acid derivatives in experimental gastric lesion models.

Glycyrrhetinic acid (Ia) and eighteen related derivatives were examined for antiulcer activity using stress-induced gastric lesions (restraint plus water immersion at 25 degrees C) in mice and rats as screening tests. Among the compounds tested, dihemiphthalate derivatives of 18 alpha- or 18 beta-olean-12-ene-3 beta,30-diol (IV, IIId), 18 beta-olean-9(11)12-diene-3 beta,30-diol (VIc), and olean-11,13(18)-diene-3 beta,30-diol (VIIc) showed potent inhibition of gastric lesion formation at a dose of 12 or 25 mg/kg (p.o.); carbenoxolone sodium (Ib) significantly suppressed the lesion formation at a dose of 500 mg/kg (p.o.). Further evaluation of the antiulcer activity was carried out mainly for compound IIId. Compound IIId (p.o.) prevented the formation of indomethacin-induced or 0.6 N HCl-induced gastric lesions; the latter antiulcer effect was noted even in the combined treatment with indomethacin, suggesting that the effect occurs independently of endogenous prostaglandins. In contrast, compound IIId had no preventive effect against Shay rat ulcer when intragastrically (i.g.) administered; further, no antisecretory effect was seen by i.g. application in pylorus-ligated rats. Administration of compound IIId for 2 weeks accelerated the healing rate of acetic acid-induced gastric ulcer in rats. No significant change in urine excretion was observed after its consecutive administration for 3 d. These results suggest that dihemiphthalate derivatives (IIId, IV, VIc, VIIc) may produce a strong antiulcer activity, probably by strengthening some gastric mucosal defensive mechanism.

Animals↗

PubMed1989