Biomedical subjects
Publications and source records attributed to M Amano.
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This study was designed to assess whether phencyclidine (PCP) produces dopamine (DA)-dependent behaviors such as licking, biting and gnawing at low doses after withdrawal from chronic haloperidol (HAL) treatment in rats. Low doses of PCP (2.5 and 5 mg/kg) produced licking, gnawing, biting and self-biting in rats after withdrawal from chronic HAL treatment, which were not observed in the vehicle-pretreated rats given PCP at the same dose range. These behaviors were similar to DA-dependent behaviors produced by methamphetamine and apomorphine in rats after withdrawal from chronic HAL treatment. The PCP-induced behaviors were attenuated by acute pretreatment of DA antagonist, HAL (0.25 mg/kg, IP). Furthermore, at doses of 5 or 7.5 mg/kg, PCP-induced head weaving and backpedalling, which were mediated by both DA and serotonin (5-HT) neurons, significantly increased in rats after withdrawal from chronic HAL-treatment. These results suggest that dopaminergic systems play an important role for PCP-induced behavioral responses.
Adult frog (Xenopus laevis) hepatocytes were found to proliferate in a culture medium containing adult homologous serum. Insulin and dexamethasone were required for a net proliferation of hepatocytes. Dose-response analysis showed that a low concentration of serum (greater than or equal to 0.5%) was enough to induce DNA synthesis and mitosis, but a higher concentration (5%) caused certain necrotic changes. Under optimal conditions, there was a two- to threefold increase in nuclei per culture 10 days after serum treatment. Heterologous sera (fetal bovine, calf and chick) showed less proliferative activity. Based on our results, hepatocyte-proliferating activity in adult frog serum is considered to be heat-unstable and acidic protein(s). Thus, adult frog serum may contain hepatopoietin possibly different from well-known growth factors.
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Sixteen patients with transitional cell carcinoma of the renal pelvis seen at our Hospital between December 1973 and February 1984 were reviewed and the diagnostic tools were evaluated. The patients (11 males, 5 females) ranged in age from 35 to 81 years (mean 63.8). Ten tumors were found on the left side and 6 on the right side. The most frequent symptom was macrohematuria (93.8%). Total nephroureterectomy including the cuff was performed in 11 cases, simple nephrectomy in 2 cases and partial nephrectomy in one case. Lymphadenectomy was performed in 4 cases. According to the general rules for clinical and pathological studies on bladder cancer in Japan, 5 cases were classified grade 1, 6 cases as grade 2 and 3 cases as grade 3. According to Cummings' staging, 2 cases were in stage 1, 4 in stage II, 7 in stage III and 3 in stage IV. The cumulative survival rate at 5 years was 34.1% by Kaplan-Meier's method. The diagnostic tool contributing to the confirmation of the renal pelvic cancer was the retrograde pyelogram in 12 out of 15 patients (80.0%).
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Administration of 5-10 mg/kg of phencyclidine (PCP) caused stereotyped behaviors including sniffing, backpedalling, head weaving and turning in rats. The PCP-induced stereotyped behaviors (backpedalling, head weaving and turning) were attenuated by serotonin (5-HT) depleters [reserpine, p-chlorophenylalanine, p-chloroamphetamine (PCA)] and 5-HT receptor antagonist (cyproheptadine). PCP-induced head weaving and turning were potentiated by 5-HT precursor (tryptophan) and 5-HT releaser (PCA). PCP-induced head weaving were potentiated also by monoamine oxidase inhibitor (pargyline) and 5-HT reuptake inhibitor (imipramine). PCP 5-10 mg/kg significantly increased the content of 5-HT in the thalamus/hypothalamus at 30 and 60 min after the injection, except PCP 5 mg/kg at 60 min. PCP 7.5 and 10 mg/kg increased the rate of increment of 5-HT by pargyline in the thalamus/hypothalamus at 30 and 60 min after the injection, respectively. PCP 10 mg/kg significantly increased the contents of 5-HIAA in the striatum and thalamus/hypothalamus at 30 min, but decreased that of 5-HIAA in all discrete brain areas except the stratium at 60 min after the injection. PCP also significantly prevented the depletion of 5-HT by PCA in all discrete brain areas except the stratium at 60 min after the injection. From these results, PCP-induced stereotyped behaviors are related to an increased serotonergic neuronal activity due to 5-HT releasing action and/or inhibitory action of 5-HT uptake-by this drug.
Plasma lipid peroxide measured as thiobarbituric acid reactive substances (TBARS) and alpha-tocopherol levels in 24 critically ill patients were compared with those of control subjects. The mean plasma alpha-tocopherol level was significantly lower and the mean TBARS level was significantly higher in critically ill patients. Eight ICU patients developed disseminated intravascular coagulation (DIC); the mean TBARS level during DIC was significantly above the mean pre-DIC level. These results indicate that lipid peroxidation may contribute to the development of DIC in critically ill patients.
A case of angiomyolipoma of the kidney with the involvement of regional lymph nodes and adjacent adipose tissue is reported. Histology of the tumor was essentially benign in either location. During three years of follow-up period, no recurrence or distant metastasis has appeared. It was considered that the tumor was benign and that the regional lymph node involvement probably represents a multicentric hamartomatous or choristomatous growth. In such an example, it is suggested that additional treatment such as radiation or chemotherapy should be avoided until a definitive evidence of distant metastasis is obtained.
A case of T cell chronic lymphocytic leukaemia (CLL) with red cell hypoplasia and neutropenia is reported. WBC was 10.0 X 10(9)/l with 78% being T lymphocytes. These T lymphocytes were positive for Fc gamma receptor and had OKT8 and Leu 2a antigens on the cell surfaces. They suppressed both erythroid and granulocyte-macrophage colony formation in normal bone marrow cultures and suppressed immunoglobulin production by normal B lymphocytes in vitro. Though the myeloid cells were preserved in the bone marrow and the values of serum immunoglobulins were within normal limits, it can be estimated from these results that red cell hypoplasia and neutropenia were partially due to the suppression of haemopoietic precursor cells by leukaemic T lymphocytes.
The effects of estrogen on the uridine uptake into cells were examined in primary cultures of liver parenchymal cells from Xenopus laevis. The total uptake of [3H]uridine into the estrogen-treated cells and its incorporation into RNA were about 1.5 times higher than the values for control cells. The uptake of [3H]adenosine and its incorporation into RNA were not affected by estrogen. An experiment in which liver parenchymal cells were double labeled with [3H]uridine and [3H]adenosine showed that estrogen elevated the specific radioactivity of the UTP pool 1.4-fold the value found for the control cells, but that of the ATP pool was not altered by estrogen. Short term labeling revealed that estrogen did not significantly alter the rate of the initial uptake of [3H]uridine into the cells, but it did stimulate [3H]uridine phosphorylation about 1.7-fold. Uridine kinase activity measured in cell-free extracts of hepatocytes treated with estrogen had a value 1.6 times that of the control cells. These data indicate that the stimulation of [3H]uridine uptake and phosphorylation in Xenopus laevis hepatocytes in the presence of estrogen is caused by the enhancement of uridine kinase activity.
When using laboratory animals (e.g., mice) for phencyclidine (PCP) tolerance studies, an essential part of the procedure is to administer the PCP in such a way that the animals received adequate doses of the drug at frequent enough intervals to reach and maintain the desired levels of tolerance or employ a osmotic minipump which is either suitable or convenient to develop a high degree of tolerance to PCP in a large number of animals in a short period. However, these methods are unfit for routine work because of repeated daily injections consume too much time and osmotic minipump comes expensive. Therefore, in this paper we attempted to develop PCP pellet suitable for tolerance development. The s.c. implantation of a 10 or 20 mg PCP pellet in the back of a conscious mouse resulted in a much more rapid development of tolerance to PCP than that produced in mice receiving daily i.p. injection of, 10 or 20 mg/kg, PCP-HCl. Assessment of and degree of tolerance to PCP by PCP pellet implantation and daily injection of PCP-HCl were evidenced by a degree of decrease in the duration of motor incoordination after the challenge with, 20 mg/kg, PCP-HCl 24 h after removal of PCP pellets or a last injection of PCP-HCl. These studies may demonstrate a substantial methodological improvement in producing a high degree of tolerance to PCP in a short period of time by means of the s.c. pellet implantation technique.
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Two cases of renal angiomyolipoma with tuberous sclerosis are reported. The first was a 42-year-old housewife with complaints of left flank pain, palpable mass at the same region and in a preshock state. Ultrasonogram of the left kidney demonstrated a large echogenic mass with fluid. Preoperative diagnosis was renal angiomyolipoma with spontaneous rupture. Emergency nephrectomy and lymphadenectomy were performed. The histopathological diagnosis was renal angiomyolipoma with nodal involvements which reflects the multicentricity of the disorder. The second was a 44-year-old housewife with dull right flank pain. CT scan showed a mass in the upper part of the kidney which had an attenuation value of -60 HU. Adrenal tumor could not be distinguished from renal tumor by selective renal angiogram. Nephrectomy was performed and histopathological diagnosis was renal angiomyolipoma. Both cases remain well. We reviewed 32 cases of renal angiomyolipoma with spontaneous rupture in the Japanese literature with respect to age, affected side, presence or absence of tuberous sclerosis, preoperative diagnosis and treatment. Previous diagnoses were done with plain film, excretory urogram and angiogram. Preoperative diagnosis of angiomyolipoma was difficult or impossible, and operative procedure of choice was nephrectomy. Now CT and ultrasonogram are the specific tools in the diagnosis of angiomyolipoma. Partial nephrectomy, enucleation or observation is selected because renal angiomyolipoma is a benign tumor.