Biomedical subjects

H Abe

Publications and source records attributed to H Abe.

At least 595 records · Page 33Linked to original sources

PubMed1996

Pressor and depressor hormones during alcohol-induced blood pressure reduction in hypertensive patients.

Alcohol acutely causes vasodilation and hypotension in Orientals. To study the mechanisms responsible for the alcohol-induced blood pressure (BP) reduction, we examined levels of various vasoactive hormones after a single intake of alcohol in twelve Japanese men with mild hypertension. On the alcohol intake day, they consumed 1 ml/kg of alcohol with an evening meal, while on the control day they took an isocaloric control drink. BP and vasoactive hormone levels were determined before and 2 h after intake of the alcohol or the control drink. BP after alcohol ingestion was significantly lower than that before drinking or on the control day. This alcohol-induced hypotension was associated with significant increases in heart rate, plasma catecholamines and plasma renin activity (PRA). The changes in heart rate and plasma noradrenaline were inversely related to the changes in BP. Plasma levels of vasopressin and insulin were lower in the alcohol period than in the control period, but these changes were not correlated with the changes in BP. Levels of aldosterone, cortisol, atrial natriuretic peptide, prostaglandin (PG) E2, 6-keto-PGF1 alpha, beta-endorphin, and cyclic GMP were not significantly different between the alcohol and the control periods. These results suggest that changes in pressor hormones may not contribute to the acute hypotensive effect of alcohol, and that the sympathetic nervous system is activated by the BP reduction. The levels of the depressor hormones measured also appear to play no role in alcohol-induced hypotension.

Adult↗

PubMed1996

Clinicopathological study of choroid plexus tumors: immunohistochemical features and evaluation of proliferative potential by PCNA and Ki-67 immunostaining.

This report concerns the retrospective immunohistochemical characterization and evaluation of the proliferative potential of eight choroid plexus tumors (CPTs) that included six cases of choroid plexus papilloma (CPP), one of whom had a recurrence, and two cases of choroid plexus carcinoma (CPC). Antibodies to prealbumin, glial fibrillary acidic protein (GFAP), vimentin, keratin, and carcinoembryonic antigen (CEA) were used to determine the immunohistochemical features of interest. The proliferative potential was evaluated with antibodies to proliferating cell nuclear antigen (PCNA) and Ki-67. Antibody binding was visualized by the avidin-biotin-peroxidase complex (ABC) method. Immunoreactivity was scored on a-to 4+ scale, and in the case of PCNA and Ki-67, expected as staining index (SI). All seven CPP specimens were immunostained for prealbumin, but not for CEA. Expression of GFAP, vimentin and keratin varied from one CPP case to another. Both CPCs expressed CEA, but not prealbumin, GFAP and keratin; one of them was vimentin-positive. As determined by immunostaining for Ki-67, the proliferative potential was lower in the CPPs than in the CPCs. Among the former, the highest Ki-67 SI was seen in the primary lesion of a recurring papilloma. On the other hand, immunostaining for PCNA gave less consistent SI values. Our results show that immunohistochemical assays for prealbumin and CEA expression are of significant value for the differential diagnosis of CPPs and CPCs, and that high Ki-67 SI values may serve as an indicator of CPP recurrence, even if the primary lesion is benign.

Adult↗

PubMed1995

Regulatory role of CD38 (ADP-ribosyl cyclase/cyclic ADP-ribose hydrolase) in insulin secretion by glucose in pancreatic beta cells. Enhanced insulin secretion in CD38-expressing transgenic mice.

Cyclic ADP-ribose (cADPR) serves as a second messenger for Ca2+ mobilization in insulin secretion, and CD38 has both ADP-ribosyl cyclase and cADPR hydrolase activities (Takasawa, S., Tohgo, A., Noguchi, N., Koguma, T., Nata, K., Sugimoto, T., Yonekura, H., and Okamoto, H. (1993) J. Biol. Chem. 268, 26052-26054). Here, we produced transgenic mice overexpressing human CD38 in pancreatic beta cells. The enzymatic activity of CD38 in transgenic islets was greatly increased, and ATP efficiently inhibited the cADPR hydrolase activity. The Ca2+ mobilizing activity of cell extracts from transgenic islets incubated in high glucose was 3-fold higher than that of the control, suggesting that ATP produced by glucose metabolism increased cADPR accumulation in transgenic islets. Glucose- and ketoisocaproate-induced but not tolbutamide- nor KCl-induced insulin secretions from transgenic islets were 1.7-2.3-fold higher than that of control. In glucose-tolerance tests, the transgenic serum insulin level was higher than that of control. The present study provides the first evidence that CD38 has a regulatory role in insulin secretion by glucose in beta cells, suggesting that the Ca2+ release from intracellular cADPR-sensitive Ca2+ stores as well as the Ca2+ influx from extracellular sources play important roles in insulin secretion.

ADP-ribosyl Cyclase↗

PubMed1995

Morphological abnormalities in the hippocampus of the weaver mutant mouse.

The lamination of the hippocampus in the homozygous B6CBA weaver mouse (wv/wv) was compared with that in normal B6CBA littermates (+/+) and C57BL/6J mice using Nissl and Timm's staining. In Nissl-stained preparations, the normal littermates exhibit a compact, regular arrangement of pyramidal cells in area CA3 of the hippocampus. In contrast, in homozygous weaver mutant mice, the pyramidal cell layer of area CA3 frequently appears to be thicker than normal with an apparent increase of neuropil, as evidenced by the presence of cell-free spaces within the layer. Also, small ectopic clusters of pyramidal cells and sometimes the subdivision of the pyramidal cell layer into 2 or 3 layers were found throughout the dorsoventral extent of the hippocampus. In Timm's stained preparations of the normal mouse hippocampus, two clearly separated bundles of axons were seen emerging from the hilus: one bundle running above the pyramidal cell layer of area CA3 (i.e., the suprapyramidal mossy fiber layer, SPMFL), and the second bundle running below the pyramidal cell layer (i.e., the infrapyramidal mossy fiber layer, IPMFL). In contrast, in some homozygous weaver mice, the origin of the mossy fiber bundles is clearly different from normal; specifically, mossy fibers emerge in a diffuse fashion from the area between suprapyramidal and infrapyramidal mossy fiber layers. In other weaver mice, short, discontinuous bundles diverge from the infrapyramidal mossy fiber layer and invade the thickened pyramidal cell layer. In addition, ectopic pyramidal cells are situated below the IPMFL in area CA3. The morphological changes observed in hippocampus of weaver mutants are likely to be secondary to a more basic genetic defect.

Animals↗

PubMed1995

The role of radiotherapy in the management of spinal cord glioma.

PURPOSE: To determine the role of radiotherapy in the management of spinal cord gliomas. METHODS AND MATERIALS: Thirty-six patients with spinal cord glioma treated between 1979 and 1993 were examined. The patients had 13 astrocytic tumors (7 astrocytomas, 4 anaplastic astrocytomas, 2 glioblastomas), 22 ependymal tumors (18 ependymomas, 4 myxopapillary ependymomas), and 1 unclassified glioma. Fifteen of the patients were treated by surgery alone, but the remaining 21 patients also received postoperative radiotherapy. Total resection was performed on 1 astrocytoma and 13 ependymomas. In general, 40-50 Gy/16-20 fractions/4-5 weeks were given after parital resection, but no radiotherapy was given after total resection. RESULTS: Actuarial survival was significantly better for patients with ependymal tumors than for those with astrocytic tumors (p = 0007), 5-year actuarial survival rates being 96% and 50% for patients with ependymal tumors and astrocytic tumors, respectively. For patients with ependymal tumors, there was no difference in motor function and survival between those with total resection and those with partial resection followed by radiotherapy. Actuarial 3-year survival was 80% for patients with astrocytomas and 40% for those with anaplastic astrocytomas plus glioblastomas. The difference in the degree of motor function between the patients treated with radiotherapy and those without radiotherapy was not statistically significant. One anaplastic astrocytoma and one glioblastoma patient have lived longer than 4 years after radical treatment including radiocordectomy, or irradiation using doses larger than the tolerance threshold of the spinal cord. CONCLUSION: Postoperative conventional radiotherapy is indicated after less than total resection of low-grade ependymal tumors and astrocytomas but not after total resection of ependymomas. Radiocordectomy may be an option for certain cases with high-grade astrocytic tumors.

Adolescent↗

PubMed1995

Neurokinin receptor antagonists inhibit the binding of growth hormone-releasing peptide to EP-1 human neuroblastoma cells.

KP-102, a second generation growth hormone-releasing peptide, specifically bound to the human neuroblastoma cell line, EP-1, cultured in vitro with a Kd value comparable to that in cell membranes of rat pituitary and hypothalamus. By crosslinking study, the molecular size of the KP-102-receptor complex was found to be approximately 80kDa. Substance P analogue, as well as nonpeptidyl antagonists of the neurokinin receptor, competed with KP-102 in its binding to EP-1 cells, although neither substance P nor substance K affected the binding. These results suggest that KP-102 binds to a receptor-like molecule resembling neurokinin receptor.

Alprostadil↗

PubMed1995

A preadipocyte clonal line from bovine intramuscular adipose tissue: nonexpression of GLUT-4 protein during adipocyte differentiation.

A clonal bovine intramuscular preadipocyte (BIP) line has been established from the intramuscular white adipose tissue of the M. longissimus thoracis in each of three Japanese Black cattle. Exponentially growing BIP cells exhibited a fibroblastic appearance. Adipocyte differentiation was initiated by treating confluent BIP cells with differentiation medium containing insulin and dexamethasone. Small lipid droplets appeared 5-6 days after stimulation and occupied a large fraction of the cell volume at 10 days and beyond. During the adipose conversion, the incorporation of acetate to the cells gradually increased by 10-fold and reached a maximum at day 5. However, incorporation of glucose increased only 3-folds prior to this conversion, even though GLUT-1 level increased by 13-fold at day 7. GLUT-4, on the other hand, was not detected during the course of differentiation. These results suggested that adipose tissue metabolisms in ruminants were different from that of non-ruminants.

Acetates↗

PubMed1995

Two distinct oscillators in the rat suprachiasmatic nucleus in vitro.

In the rat suprachiasmatic nucleus slice culture, circadian rhythms in the release of arginine vasopressin and vasoactive intestinal polypeptide were measured simultaneously and longitudinally. The phase relationship between the two peptide rhythms was relatively constant in the culture without a treatment of antimitotic drugs but became diverse by an introduction of antimitotics, which is generally used to reduce the number of glial cells. By monitoring the two rhythms continuously for 6 days, different periods were detected in culture with the antimitotic treatment. Furthermore, N-methyl-D-aspartate shifted the phase of the two peptide rhythms in the same culture differently. These results indicate that the arginine vasopressin and vasoactive intestinal polypeptide release are under control of different circadian oscillators.

Animals↗

PubMed1995

Adenocarcinoma arising from gastric immature teratoma. Report of a case in an adult and a review of the literature.

BACKGROUND: Gastric teratoma is an uncommon tumor and usually occurs in infancy or childhood. To the authors' knowledge, malignant transformation in gastric teratoma has not been reported previously. METHODS: An 83-year-old Japanese man presented with a large polypoid gastric tumor composed of teratomatous components and invasive adenocarcinoma. Numerous blocks of this tumor were analyzed histologically and immunohistochemically. RESULTS: Histologically, the gastric tumor consisted of teratomatous components with diverse maturation, such as fibroblastic mesenchymal cells, striated muscle cells, cartilaginous islands, neuroepithelial components, glial tissues, squamous cell nests, glandular components, and foci of adenocarcinoma infiltrating the benign gastric tissues adjacent to the tumor stalk. Metastatic foci of teratomatous components in the resected lymph nodes contained adenocarcinomatous glands. An immunohistochemical study helped confirm the differentiation in the immature components and the differential diagnosis between atypical neuroepithelial cells and the adenocarcinoma. CONCLUSION: This study indicates that the adenocarcinoma arose from immature gastric teratoma. A review of the literature suggests that this is the oldest reported patient with gastric teratoma and to the authors' knowledge is the first report describing gastric teratoma with malignant transformation.

Adenocarcinoma↗

PubMed1995

Immunological detection and characterization of an estrus-associated antigen in the goat oviduct.

The present study was designed to investigate the possibility that the goat oviduct produces specific substance(s) similar to the oviductal glycoprotein (BOGP) of the bovine oviduct. Oviductal flushings obtained from goats at the follicular and luteal phases of the estrous cycle were examined by immunoblotting for the presence of material that cross-reacted with monoclonal antibodies (MAbs) specific for BOGP. The MAbs immunoreacted with a broad band with a molecular mass of protein of about 97 kDa in the flushings of goat oviducts after fractionation of proteins by electrophoresis under reducing conditions. The antigen was present in flushings obtained from the ampullar segments of oviducts from goats at the follicular stage, but this antigen could hardly be detected in the flushings from the ampulla at the luteal phase and or the flushings from the isthmus at either the follicular or the luteal phase. This antigen was not detected in uterine flushings, follicular fluid, or serum. An immunohistochemical study demonstrated that the MAbs reacted specifically with the epithelial cells of the goat oviduct. Intense labeling was observed in the ampullar and fimbrial epithelia of goat oviducts at the follicular phase, but the immunohistochemical reaction was very weak at the luteal phase. In the isthmus, the reaction was faint during both the follicular and the luteal phase. No specific immunohistochemical reactivity with the MAbs was observed with other tissues from the reproductive tract or with nonreproductive tissues. Immunofluorescent staining showed that the antigen was associated with the zona pellucida of goat ovarian eggs that had been incubated with ampullar flushings from goats at the follicular stage.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1995

Secretory products of bovine oviductal epithelial cells support the viability and motility of bovine spermatozoa in culture in vitro.

The ability of secretions from the bovine oviduct to maintain the viability and motility of bovine spermatozoa was investigated by incubating frozen-thawed spermatozoa with oviductal flushings, uterine flushings, or the medium from cultures of oviductal epithelial cells and endothelial cells. The flushings obtained from both oviducts and uteri were effective for the maintenance of the viability and motility of spermatozoa, irrespective of the stage of the estrous cycle at which they had been collected. The flushings obtained from the ampullar region of oviducts at the follicular phase of the estrous cycle were most effective for the maintenance of viability and motile activity, for example, the forward motion of spermatozoa. Sperm viability and motility were also maintained by the medium from 6-hour culture of epithelial cells obtained from oviducts at the follicular phase of the estrous cycle. In contrast, the medium derived from bovine fetal artery endothelial cells had no significant effect on sperm viability and motility. These results suggest that the fluids of the female reproductive tract, in particular, the oviductal fluids at the follicular stage, provide a suitable environment for the maintenance of the viability and motility of bovine spermatozoa. It is also suggested that secretory product(s) of oviductal epithelial cells may play an important role in sustaining both the viability and motility of spermatozoa.

Animals↗

PubMed1995

Biochemical characterization of a bovine oviduct-specific sialo-glycoprotein that sustains sperm viability in vitro.

A bovine oviduct-specific glycoprotein (BOGP) that sustained the viability of bovine spermatozoa in vitro was purified from an extract of bovine oviducts. The amino-terminal amino acid sequence of BOGP was found to be a homologous with that of oviductin, a protein from hamster that was recently characterized by Mallete and Bleau (1993: Biochem. J. 295, 437-445). Purified BOGP was characterized as a sialo-glycoprotein containing N-linked and O-linked sialo-oligosaccharides side chains with galactose, mannose, N-acetyl-D-galactosamine, N-acetyl-D-glucosamine, fucose and sialic acids in its core protein (57 kDa). Intact BOGP has a wide range of isoelectric points (pIs) from 6.5 to 3.0 but a narrow range of molecular masses around 95 kDa. On isoelectric focusing of neuraminidase-treated BOGP (AS-BOGP), a narrow band with a pI of 9.3 was observed, and the ability of AS-BOGP to maintain sperm viability was negligible. We propose that BOGP is a mucin-type sialo-glycoprotein with a molecular mass of 72 kDa that contains one N-linked and approx. 15 O-linked sialo-oligosaccharide chains. These side chains appear to be important for the maintenance of sperm viability.

Amino Acid Sequence↗

PubMed1995

A new polyamine 4-aminobutylcadaverine. Occurrence and its biosynthesis in root nodules of adzuki bean plant Vigna angularis.

Root nodules of adzuki bean plant (Vigna angularis) contained a novel polyamine. The chemical structure of the new polyamine was determined to be NH2(CH2)5-NH(CH2)4NH2 (4-aminobutylcadaverine) based on gas chromatography-mass spectrometry. The occurrence of 4-aminobutylcadaverine was specific to the root nodules, since the unusual triamine was not detected in other organs of the adzuki bean plant. Bacteroids, isolated from root nodules, contained both sym-homospermidine and 4-aminobutylcadaverine, whereas the plant cytosol fraction contained large quantities of putrescine and cadaverine. A cell-free extract of bacteroids showed the ability to form this triamine from putrescine and cadaverine under the presence of NAD+ and K+. 1,3-Diaminopropane and NADH were inhibitory for the synthesis of both sym-homospermidine and 4-aminobutylcadaverine. [1,4-15N]Putrescine was incorporated not only into sym-homospermidine but also into 4-aminobutylcadaverine by the cell-free extract of bacteroids when incubated with excess cadaverine. Analysis of the fragment ion peaks in the 15N-enriched 4-aminobutylcadaverine indicated the transfer of a aminobutyl moiety to the amino terminus of cadaverine. These results suggest that, in adzuki bean, 4-aminobutylcadaverine is formed through the action of homospermidine synthase in nodule bacteroids under a cadaverine-rich environment.

Cadaverine↗

PubMed1995

Antithrombin III Kumamoto II; a single mutation at Arg393-His increased the affinity of antithrombin III for heparin.

Abnormal antithrombin III (AT III) was found in a 30-year-old woman who suffered from recurrent thrombosis during pregnancy and the postpartum period. Among her family members, only her father had recurrent episodes of deep vein thrombosis of the lower extremities, from his youth. The antithrombin and antifactor Xa heparin cofactor activities of the proposita's plasma were 61% and 42% of normal, respectively. The progressive antithrombin and antifactor Xa activities were also decreased to 55% and 58% of normal, respectively. The immunoreactive level of AT III was within the normal range (23.1 mg/dl). Analysis of the proposita's plasma by crossed immunoelectrophoresis in the presence or absence of heparin and by affinity chromatography on heparin-Sepharose revealed that the proposita's AT III had apparently normal affinity for heparin. Nucleotide sequencing of 7 exons of the proposita's AT III gene amplified by polymerase chain reaction (PCR) disclosed that the second base of codon 393 comprised both G and A, indicating Arg393-His conversion. The base sequences of exons 1, 2, 3a, 3b, 4, and 5 were normal, excluding any other mutation. These findings indicated that the proposita's AT III was a variant of AT III at the thrombin binding site and that the proposita was a heterozygote for the abnormality. Heparin affinity of purified abnormal AT III from the proposita's plasma was demonstrated to be increased upon affinity chromatography using heparin-Sepharose, suggesting that the mutation (Arg393-His) per se could possibly increase the affinity of antithrombin III for heparin. For this variant AT III (Arg393-His), the name AT III Kumamoto II is proposed.

Adult↗

PubMed1995

Concentration of cofilin, a small actin-binding protein, at the cleavage furrow during cytokinesis.

Cofilin is a small actin-binding protein which regulates actin polymerization in a pH-dependent manner. Immunofluorescence microscopy with a monoclonal antibody for cofilin revealed that this protein is temporarily concentrated at the contractile ring during cytokinesis. Cofilin appeared to accumulate rapidly at the contractile ring during late stages of furrowing, and was finally enriched at the midbody. The concentration of cofilin at the contractile ring was observed in several kinds of cultured cells. Furthermore, cofilin introduced into living cells by a microinjection method was also concentrated at the contractile ring. These results suggest that cofilin is involved in actin reorganization during cytokinesis.

Actin Cytoskeleton↗

PubMed1995

Bovine oviduct-specific glycoprotein: a potent factor for maintenance of viability and motility of bovine spermatozoa in vitro.

In the cow, a specific glycoprotein--bovine oviduct-specific glycoprotein (BOGP)--is secreted by the epithelial cells of the oviduct at the follicular stage of the estrous cycle. In this study, we examined the effects of purified BOGP on the viability and motility of bovine spermatozoa in culture in vitro. Frozen-thawed bovine spermatozoa were incubated in modified Tyrode's solution (TALP) that contained purified BOGP (TALP-BOGP). In TALP-BOGP, both the viability and motility of bovine spermatozoa were more effectively maintained than in the control medium without any added protein. The increases in both the viability and motility of spermatozoa were dose-dependent. Spermatozoa were also incubated in TALP medium supplemented with bovine serum albumin, egg albumin, lactalbumin, or gastric mucin, and their viability and motility in these media were compared with that in TALP-BOGP. Both the viability and motility of spermatozoa were more effectively maintained in TALP-BOGP throughout a 12-hr incubation than in other media tested. An immunolabeling study demonstrated that a monoclonal antibody specific for BOGP reacted with the posterior region of the head, the middle portion, and the tail of spermatozoa that had been incubated with TALP-BOGP, suggesting that BOGP becomes specifically associated with particular regions of the spermatozoon. These results suggest that BOGP is a potent factor for maintenance of the viability and motility of sperm. On the basis of the present results, we also propose that BOGP may play an important role in sperm functions during the reproductive process.

Animals↗

PubMed1995

Role of technetium-99m pertechnetate scintigraphy in the management of extra-abdominal fibromatosis.

The purpose of this study was to investigate technetium-99m pertechnetate (Tc-99m) as a tumor-scanning agent in patients with extra-abdominal fibromatosis, and to establish the sensitivity of this type of scintigraphy. Eleven patients with extra-abdominal fibromatosis were studied: all but one having postsurgical recurrences. Of the 11 patients, diagnosed histologically, 5 underwent repeated Tc-99m scintigraphic follow-up examinations. The injected 370 MBq Tc-99m gave us an early scintigram within 10 min and a delayed one 2 h later. For adequate comparison, the region of interest (ROI) of the scintigram was placed over the tumor. The tumor-to-background (T/BG) count ratio was computed. Extra-abdominal fibromatoses, even recurrences, were demonstrated scintigraphically in both the early and the delayed phase, in all 11 patients. The average T/BG ratio was 2.11 in the early scintigram and 2.15 in the delayed one. The sensitivity and the specificity were both 100%. Tc-99m scintigraphy has proved useful in detecting extra-abdominal fibromatoses and in the follow-up of patients.

Adult↗

PubMed1995

Circadian modulation in photic induction of Fos-like immunoreactivity in the suprachiasmatic nucleus cells of diurnal chipmunk, Eutamias asiaticus.

Photic induction of immediate early genes including c-fos in the suprachiasmatic nucleus (SCN) has been well demonstrated in the nocturnal rodents. On the other hand, in diurnal rodents, no data is available whether the light can induce c-fos or Fos in the SCN. We therefore examined whether 60 min light exposure induces Fos-like immunoreactivity (Fos-lir) in the SCN cells of diurnal chipmunks and whether the induction is phase dependent, comparing with the results in nocturnal hamsters. We also examined an effect of light on the locomotor activity rhythm under continuous darkness. Fos-lir was induced in the chipmunk SCN. The induction was clearly phase dependent. The light during the subjective night induced strong expression of Fos-lir. This phase dependency is similar to that in hamsters. However, unlike in hamsters, the Fos-lir was induced in some SCN cells of chipmunks exposed to light during the subjective day. In the locomotor rhythm, on the other hand, the light pulse failed to induce the phase shift at phases at which the Fos-lir was induced. These results suggest that the photic induction of Fos-lir in the diurnal chipmunks is gated by a circadian oscillator as well as in the nocturnal hamsters. However, the functional role of Fos protein may be different in the diurnal rodents from in the nocturnal rodents.

Animals↗