Quantitative estimation of intrasplenically transplanted hepatocytes in Gunn rats using technetium-99m-diethylenetriaminepentaacetic acid-galactosyl-human serum albumin.
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Publications and source records attributed to M Minagawa.
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Effects of histamine on the testicular polymodal receptors were studied in vitro using canine testis-spermatic nerve preparations. Histamine induced distinct increase in the discharge rate in 6 out of 17 units tested (high responders), while it only weakly excited the remaining 11 units (low responders). The bradykinin response of low responders tended to be slightly facilitated by pretreatment with histamine, while that of high responders tended to be suppressed. Significant correlation was observed between the magnitude of histamine-induced discharges and the magnitude of change in the bradykinin responses.
We report three neonates with transient hypoparathyroidism with elevated parathyroid hormone (PTH) levels to clarify further the pathogenesis of late neonatal hypocalcemia and calcium homeostasis. Clinical signs were seizures starting at age of 10 and 11 days. The biochemical features were characterized by transient hypocalcemia and hyperphosphatemia due to a high transport maximum of the phosphate/glomerular filtration rate, despite high PTH levels. All had normal magnesium and calcidiol levels (at least 5 micrograms/l) for their age, and this precludes hypoparathyroidism due to low magnesium levels and hyperparathyroidism due to overt vitamin D deficiency. To diagnose pseudohypoparathyroidism type I, intravenous human PTH (1-34) infusions were performed; however, they showed brisk responses of plasma and/or urine cyclic AMP in response to the PTH infusion, but the phosphaturic response to the PTH was sluggish compared to the controls. All three showed an increase in serum alkaline phosphatase activity, suggesting PTH stimulation of osteoblasts. They were treated initially with calcium lactate or (1 alpha)-hydroxycalciol/calcitriol. Their hypoparathyroid condition, however, was transient; they maintained normal serum calcium and PTH levels without medication before the age of 6 months. The etiology, possibly intracellular signal transduction distal to cyclic AMP and/or distinct from adenylate cyclase in the kidney, is developmental and the condition was resolved completely within 6 months of age. We have termed this condition "transient pseudohypoparathyroidism of the neonate".
A rare adult autopsy case of Down syndrome was reported. The patient was a 36-year-old male, whose chromosome analysis revealed 47, XY, +21. He showed typical systemic AA-amyloidosis and numerous senile plaques in the brain. Senile plaques were diffuse or primitive. They were composed of beta-protein, but negative for Congo-red stain. There were few neurofibrillary changes in the para hippocampal gyri. Nucleus basalis Meynert showed no significant lesion. The distribution of these plaques had some characteristics different from that for Alzheimer's disease. In the brain involvement of systemic AA-amyloidosis was restricted to the regions devoid of blood-brain-barrier, such as choroid plexus and pituitary gland. Cerebral beta-amyloid and systemic amyloid A protein were segregated on each side of the blood-brain-barrier. Therefore, we suggested that each amyloid might be synthesized and deposited by its own mechanism. Electronmicroscopically Hirano's body was identified in the hippocampal gyri.
In elucidating the possible involvement of histamine (His) in hyperalgesia to heat, the effects of His on the heat response of testicular polymodal receptors were studied in vitro in canine testis-spermatic nerve preparations. His (100 and 1000 microM) induced discharges > 0.5 impulses/s (high-responders) in about one third of units tested. His (> or = 10 microM) facilitated the heat response irrespective of whether His alone induced substantial excitation, and the magnitude of facilitation at 100 microM did not differ between high- and low-responders (His-induced discharges < or = 0.5 impulses/s). Conduction velocity of high-responders at 100 microM (2.2 +/- 0.9 m/s, n = 5) was slower on average than that of low-responders (12.9 +/- 1.6 m/s, n = 9). The sensitizing effect of His reported in this paper suggests that His plays a role in hyperalgesia.
In clarifying the possible involvement of cyclic AMP (cAMP) in prostaglandin (PG) E2-induced sensitization of the bradykinin response of canine testicular polymodal receptors, the effects of forskolin, an activator of adenylyl cyclase, were studied in the presence and absence of acetylsalicylic acid (ASA, 550 microM) which blocks PG production. Forskolin (10 microM) seldom induced discharges in polymodal receptors. An unexpected outcome of this study was that forskolin induced no facilitation of the bradykinin (0.1 microM) response, both in the absence and presence of ASA. A slight yet significant suppression of the bradykinin response was instead observed in the absence of ASA. These results suggest that intracellular cAMP may be related with PG E2-induced sensitization of the bradykinin response through its decrease.
OBJECTIVE: The high-affinity growth hormone (GH)-binding protein corresponds to the extracellular domain of GH receptor. The direct role of sex steroids in pubertal bone growth may be an increased GH receptor-coupled GH action. We examine the GH-binding protein (GHBP) activity before and after the suppression of female sex steroids and the relation of GHBP to pubertal growth. PATIENTS: We studied six girls with central idiopathic sexual precocity without any prior gonadal suppression therapy. DESIGN: We measured GHBP activity before and 12, 24 and 48 weeks after the treatment with s.c. injection of a GnRH agonist (leuprolide acetate) every 4 weeks. MEASUREMENT: GHBP activity was measured by immunoprecipitation using anti-GH receptor monoclonal antibody. RESULTS: The treatment caused a decrease in the LH and FSH responses to GnRH test and plasma oestradiol, which resulted in decreased urinary GH excretion, plasma IGF-I levels, height velocity and bone age maturation. GHBP activity before the start of the treatment was normal (75 +/- 27% relative to adult pooled serum, mean +/- SD), and it was increased above adult level (122 +/- 29% at 48 weeks, P < 0.01) by the suppression of the pituitary-gonadal axis. There were significant negative correlations between GHBP and oestradiol (r = 0.452, n = 24, P < 0.05) and between GHBP and urine GH excretion (r = -0.462, n = 24, P < 0.05). CONCLUSIONS: The high-affinity GHBP is increased by the withdrawal of female sex steroid. The clinical significance of this finding may be interference with the binding of GH to its receptor resulting in a reduced IGF-I level and decreased height velocity. The mechanism warrants further study.
1. Using canine testis-spermatic nerve preparations in vitro, we studied the effects of acetylsalicylic acid (ASA), an inhibitor of cyclooxygenase, on the polymodal receptor response to heat stimulation itself and on the sensitizing effects on the heat and bradykinin responses induced by strong heat stimulation (55 degrees C for 30 s). 2. Greater heat responses tended to be strongly suppressed by ASA (550 microM), with a significant correlation observed between the response magnitude and the magnitude of the suppression (r = 0.88 for the response at 45 degrees C; r = 0.83 for the response at 48 degrees C). The change in the heat response at 48 degrees C from 1.18 +/- 0.19 to 0.62 +/- 0.11 imp/s was statistically significant (n = 21, P < 0.01). 3. After stimulation at 55 degrees C in the presence of ASA, resting discharges at 34 degrees C appeared in only 2 of the 21 units tested. The responses at 45 and 48 degrees C, however, were significantly potentiated after this stimulation (those at 45 degrees C from 0.12 +/- 0.05 to 2.19 +/- 0.51 imp/s, mean +/- SE; those at 48 degrees C from 0.62 +/- 0.11 to 2.42 +/- 0.49 imp/s; P < 0.01, n = 21 for both). Sensitization was observed up to 50 min after stimulation at 55 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)
The sensitizing effect of prostaglandin (PG) E2 on the heat response of testicular polymodal receptors was studied in vitro by recording single polymodal receptor activities from the testis-spermatic nerve preparations excised from deeply anesthetized dogs. PG E2 at 10(-7) M had no significant influence on the heat response. PG E2 at 10(-6) and 10(-5) M did not induce substantial increases in discharge rates, yet it significantly augmented the heat response. The concentration necessary for augmenting the heat response is thus 100 times greater than that (10(-8) M) previously reported for bradykinin [Naunyn-Schmiedebergs Arch. Pharmacol., 344 (1991) 368-376].
Immunohistochemical studies were carried out on the new type of cerebral cortical astrocytic inclusions recently discovered in a 20-year-old patient with maldeveloped brain and micropolygyria. The inclusions appeared as eosinophilic structures (hematoxylin and eosin stain) and did not exhibit argyrophilia (modified Bielschowsky method). The inclusions were strongly stained by the antibody against S-100 protein (S 100) and to a lesser extent by the antibody to microtubule-associated protein 1B (MAP 1B). In contrast to Rosenthal fibers, the astrocytic inclusions did not react with antibodies to alpha B-crystallin, glial fibrillary acidic protein and ubiquitin. No positive reactions were obtained with antibodies against heat-shock protein 27 (HSP 27), HSP 72, actin, vimentin, desmin, cytokeratin, myelin basic protein, beta-tubulin, MAP 2, tau protein, paired helical filament, phosphorylated neurofilament protein (NFP), nonphosphorylated NFP, synaptophysin, cathepsin D, alpha 1-antichymotrypsin, alpha 1-antitrypsin and basic fibroblast growth factor. By immunoelectron microscopy, the products of the reaction with the anti-S 100 antibody appeared as heterogeneous granular deposits and with the antibody to MAP 1B they were randomly scattered throughout the astrocytic inclusions. Our results demonstrate that the immunohistochemical profile of the recently described inclusions differs from that of Rosenthal fibers. Whether the novel inclusions are involved in congenital astrocyte dysfunction and cerebral malformation remains to be established.
A unique pathological finding of astrocytes was observed in the brain of a 20-year-old man who had severe physical and mental retardation. The brain was malformed showing micropolygyria in several cortical areas. A large number of hypertrophic astrocytes with eosinophilic granular substances in their cytoplasm were found throughout the cerebral cortex. Several staining procedures and electron microscopical examinations were carried out on these intracytoplasmic inclusion. It was found that the appearance and staining character of these inclusions were different from other astrocytic changes, especially the Rosenthal fiber, described so far. The authors consider that these inclusion bodies in cerebral cortical astrocytes represent new pathological changes of astrocytes that appear to be associated with malformation of the brain.
The relationships among element concentrations (Na, Mg, Al, P, K, Ca, Cr, Fe, Mn, Cu, Zn, Sr, total Hg, organic Hg, inorganic Hg, Pb) and stable carbon and nitrogen isotope ratios (13C/12C and 15N/14N) in animals consumed by the people called Gidra, who inhabit the lowland of Papua New Guinea, were examined. Animals analyzed included mammal, bird, fish, shellfish, reptile, crustacean, and insect. Highly significantly positive correlations were observed between total Hg concentrations and 15N/14N (r = 0.796), between organic Hg concentrations and 15N/14N (r = 0.781), and between inorganic Hg concentrations and 15N/14N (r = 0.739). This was interpreted to indicate that Hg was an element which accumulates in animals along the food chain. Based on the regression function of Hg on delta 15N, the bioconcentration factor for total, organic, and inorganic Hg was estimated to be 5.
We report a girl with the Rett syndrome who had acute encephalopathy probably induced by calcium hopantenate (HOPA). This 4-year-6-month-old girl had a history of moderate developmental delay and had received HOPA administration when first admitted at 2 years 6 months of age with hypoglycemia, hyperammonemia, lactic and pyruvic acidemia, and non-ketotic dicarboxylic aciduria. After this episode, she showed the rapid destructive stage of the Rett syndrome, i.e., severe psychomotor retardation with loss of speech, peculiar stereotypic hand movements, autistic behavior and seizures. Despite subsequent investigations, including analysis of urinary metabolites of organic and amino acids, measurement of serum carnitine and a muscle biopsy, we could not clarify the primary metabolic abnormalities in this girl.
General aspects in isotope biogeochemistry was summarized with emphasis on delta 15N and delta 13C contents in plants and animals in natural ecosystems. In the estuary, the variation of isotope ratios were principally governed by the mixing of land-derived organic matter, marine phytoplankton, and seagrasses. A clear cut linear relationship between animal delta 15N and its trophic level was obtained in the Antarctic food chain system. Several current efforts to use the stable isotopes for food web analysis were demonstrated for some terrestrial and marine systems as well as human food web.
1. Whether bradykinin (BK), which is known as an endogenous pain-producing substance, induces augmentation of the discharges of polymodal receptors evoked by heat stimulation was investigated in in vitro canine testis-superior spermatic nerve preparations. 2. The heat response was significantly augmented by pretreatments with BK at concentrations greater than 0.094 nM, whereas BK induced significant increases in the mean discharge rates at concentrations above 9.4 nM. Both effects increased in a concentration-dependent manner. The augmenting effect of BK on the heat response diminished within 10 min after application of BK, regardless of concentration. 3. When 9.4 nM BK was applied in a mixture with 940 nM NPC349, a B2 receptor antagonist, the averaged mean discharge rate evoked by BK and the averaged augmenting effect were both significantly suppressed compared with those induced by BK given alone. 4. The augmenting effect of BK on the heat response of polymodal receptors could be observed even in the absence of BK-evoked discharges per se in several cases in which low concentrations of BK or BK plus B2 antagonists were given. 5. These findings suggest that the augmenting effects of BK on the heat response depend on B2 receptor-mediated intracellular processes acting in parallel to, but not directly on, the impulse-generation mechanism of the heat response of the polymodal receptor.
The effects of intra-arterial infusion of degradable starch microspheres (DSM) on liver tissue blood flow were estimated in rat with liver carcinoma induced by 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB) administration. Tissue blood flow of tumor and normal liver was measured simultaneously by Laser blood flowmeter. Tissue blood flow of tumor and normal liver was 13.3 +/- 6.9, 13.2 +/- 4.3 (ml/min/100 g), respectively. After intra-arterial infusion of DSM, tissue blood flow of both tumor and normal liver decreased to the same degree as that at hepatic artery occlusion and then gradually recovered. This gradual recovery of tissue blood flow was supposed to express the process of resolution of DSM by alpha-amylase. The recovery time of tissue blood flow following intra-arterial infusion of DSM was 27.3 +/- 4.0 min (DSM 20 mg/kg) and 70.0 +/- 23.6 min (DSM 30 mg/kg) in tumor and 20.0 +/- 3.3 min and 36.5 +/- 18.0 min, respectively, in normal liver. Thus, the blocking effect of blood flow by DSM was different between tumor and normal liver and proved to be more persistent in the former.
Effects of opioids on the activity of visceral nociceptors were tested using the in vitro testis-spermatic nerve preparations excised from deeply anesthetized dogs. Morphine, DADLE and dynorphin (10 microM) elicited discharges of polymodal receptors in approximately 1/3 of the tested cases. The incidence of the excitatory response of morphine increased at higher concentrations. The excitatory responses were quite variable among preparations and showed a strong tendency for tachyphylaxis. Similar increases in discharges were elicited when morphine was applied during the steady state of the response evoked by bradykinin (BK) or BK mixed with prostaglandin E2. Pretreatment of morphine for 5 min significantly augmented the subsequent BK responses for 30 min or more. Naloxone per se induced neither excitation nor augmentation of the subsequent BK response, however it reversed the augmenting effect of morphine on BK response. In contrast with previous reports proposing peripheral analgesic effects of opioids, suppressive effects on nociceptors were never observed in the present experiment. Peripheral effects of opioids were discussed.
In previous studies (Shikwa Gakuho 80: 473-485, 1471-1486, 1980), the authors have reported on sealing properties in vitro. But the recent development of many new sealers makes necessary a detailed reexamination at this time. The experimental materials were as follows; Zinc oxide eugenol sealer......Canals Calcium hydroxide eugenol sealer......CRCS, Dentalis KEZ Calcium hydroxide guaiacol sealer......FR Hydroxyapatite sealer......Finapec APC, Apatite root sealer TYPE III The experimental procedure employing a glass tube and the dye-penetration method was similar to the one used in previous studies. Results of the investigation; 1. Degrees of dye penetration were classified into 3 types i) Immediate penetration through the zone between the material and the glass tube within 2 days.--Apatite root sealer TYPE III, Dentalis KEZ ii) Little penetration within 12 hours but gradual penetration to the deep zone thereafter.--CRCS, Canals iii) Slight penetration within 7 days and then gradual penetration 1/5 of the way through the zone between the material and the glass tube.--Finapec APC 2. Dye penetrated through the material in the case of apatite root sealer TYPE III and FR.