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H Izumi

Publications and source records attributed to H Izumi.

At least 19 recordsLinked to original sources
PubMed1992

Origins of parasympathetic postganglionic vasodilator fibers supplying the lips and gingivae; an WGA-HRP study in the cat.

Application of WGA-HRP to the mandibular lip and buccal gingiva of the cat resulted in retrograde labeling in the ipsilateral otic ganglion (OG), whereas labeled neurons appeared in the pterygopalatine ganglion (PPG) as well as in the OG when the tracer was injected into the maxillary lip and buccal gingiva. The results suggest that both the facial and the glossopharyngeal preganglionic vasodilator fibers supplying the mandibular lip and buccal gingiva mediated in the OG, and those innervating the maxillary lip and buccal gingiva are mediated in the PPG and the OG.

Animals↗
PubMed1992

Nucleotide sequence of a cDNA clone encoding a major allergenic protein in rice seeds. Homology of the deduced amino acid sequence with members of alpha-amylase/trypsin inhibitor family.

A cDNA clone of rice major allergenic protein (RAP) was isolated from a cDNA library of maturing rice seeds. The cDNA had an open reading frame (486 nucleotides) which coded a 162 amino acid residue polypeptide comprising a 27-residue signal peptide and a 135-residue mature protein of M(r) 14,764. The deduced amino acid sequence of RAP showed a considerable similarity to barley trypsin inhibitor [1983, J. Biol. Chem. 258, 7998-8003] and wheat alpha-amylase inhibitor [1981, Phytochemistry 20, 1781-1784].

Allergens↗
PubMed1992

Two cell lines established from mixed müllerian tumors of the uterus. Morphologic, immunocytochemical, and cytogenetic analyses.

To clarify the cellular origin and characteristics of malignant mixed müllerian tumor (MMMT), the authors investigated two cell lines (designated as FU-MMT-1 and FU-MMT-2) established from two patients with heterologous MMMT of the uterus. Both cell lines propagated continuously for 83 and 55 serial passages over 1.5 years, respectively. Morphologically, FU-MMT-2 was a mixture of carcinoma cells and sarcoma cells with predominance of carcinoma cells; FU-MMT-1 only had a sarcomatous element with distinct rhabdomyoblastic differentiation. Immunocytochemically, the sarcoma cells of each cell line expressed, not only myogenic and mesenchymal antigens (desmin, myoglobin, and vimentin), but also epithelial antigens, including epithelial membrane antigen and keratin. The carcinoma cells in FU-MMT-2 were positive for the epithelial antigens and vimentin and negative for desmin and myoglobin. Both lines had abnormal karyotypes; the modal chromosome numbers of FU-MMT-1 and FU-MMT-2 were 47 and 80, respectively. In addition, FU-MMT-1 had trisomy 8, and FU-MMT-2 had complex structural abnormalities. When transplanted into nude mice, FU-MMT-1 reproduced and maintained the characteristics of the original tumor. These cell lines and xenografts appear to provide a useful system for studying the biologic behavior, cytogenetic features, and histogenesis of MMMT. In conclusion, the presence of epithelial antigens in the sarcomatous and carcinomatous elements seemed to support the hypothesis that both elements are derived from a common stem cell.

Aged↗
PubMed1992

Somatosensory afferents in the parasympathetic vasodilator reflex in cat lip.

Somato-parasympathetic reflexive vasodilatation elicited by activation of the nociceptors in the oro-facial areas of the cat was investigated. Changes in lower lip blood flow monitored by a laser Doppler flowmeter took place in pentobarbital-anesthetized and artificially respirated cats. Pinch and heat stimulation of the oro-facial areas evoked a blood flow increase similar to that of electrically induced vasodilatation. Sustained increased responses in blood flow were obtained when a 1% capsaicin solution was applied to the tongue. These results show that the C-polymodal nociceptor is a strong candidate for a receptor that provokes somato-parasympathetic vasodilatation. Capsaicin-insensitive nerve fibers, however, also participate because electrical stimulation of the capsaicin-treated tongue evoked vasodilatation. The correlation between noxious stimulation-induced vasodilatation and systemic blood pressure change also is discussed.

Animals↗
PubMed1992

Selective excitation of parasympathetic nerve fibers to elicit the vasodilatation in cat lip.

Electrical stimulation of the tongue and the proximal cut end of the lingual nerve caused a blood flow to increase in a stimulus-intensity dependent manner in the ipsilateral lower lip of the cats. Pretreatment with hexamethonium (an autonomic ganglionic blocker, 1.0 mg/kg) abolished the vasodilator response, while atropine, phentolamine, propranolol and tripelennamine had no effect on these vasoresponses. Ipsilateral sections of either the glossopharyngeal nerve root, inferior alveolar nerve or mental nerve at the main mental foramen, but not at the posterior mental foramen, abolished the vasodilator response caused by electrical stimulation of the tongue and the lingual nerve. Electrical stimulation of the distal cut ends of the glossopharyngeal nerve root and inferior alveolar nerve caused the vasodilator and vasoconstrictor responses, whereas stimulation of the tongue and the proximal cut ends of the lingual nerve did not elicit the vasoconstrictor response. These results suggest that reflex vasodilatation in the cat mandibular division is exclusively mediated via activation of the parasympathetic nerve fibers, and that selective excitation of the parasympathetic nerve fibers in the oral area is possible.

Animals↗
PubMed1992

Purification of immunoprecipitated pemphigus foliaceus antigen fragment and its use in radioimmunoassay.

A major difficulty in biochemical studies of the pemphigus foliaceus (PF) antigen is the lack of a method for its quantitative determination. Immunofluorescence blocking and immunoprecipitation methods are semiquantitative and time consuming. Radioimmunoassay (RIA) methods are quantitative but they require pure and stable antigen preparations that have not been available for PF. The present investigation shows the further purification of a previously described preparation of PF antigen fragment obtained from trypsinization media of mouse skin (Con A Frn) and demonstrates its usefulness in a RIA method for quantitation of the antigen. The major contaminants of the 45-kD tryptic fragment of the PF antigen (tf-PF) in immunoprecipitates of the Con A Frn with PF sera were identified as H and L chains of murine IgG and mannose-binding lectins. The IgG contaminants could be removed by avoidance of blood contamination during preparation of the Con A Frn and/or pre-absorption of the Con A Frn with protein A Sepharose. The lectins could be removed by affinity chromatography of the Con A Frn on asialofetuin column and washing the immunoprecipitates with 0.2 M alpha-methyl-mannoside. Using the purified, labeled Con A Frn in RIA, we showed that standard curves could be established and the amounts of PF antigen could be determined in different extracts without the need for electrophoresis, autoradiography, or scanning. This RIA method is rapid and can be easily used to analyze many samples, e.g., chromatographic fractions and extracts made from different tissues.

Animals↗
PubMed1992

Somatosensory stimulation causes autonomic vasodilatation in cat lip.

1. Electrical stimulation of the infra-orbital nerve and the maxillary buccal gingiva caused an increase in ipsilateral lip blood flow in a stimulus intensity-dependent manner in anaesthetized cats. 2. The reflex vasodilator response was resistant to blockade by antimuscarinic (atropine), antiadrenergic (phentolamine and propranolol) and antihistaminergic (tripelennamine) but sensitive to ganglionic blocking agent (hexamethonium). 3. The reflex vasodilator response was unaffected by section of the ipsilateral cervical sympathetic trunk and facial nerve root, but was completely abolished by ipsilateral section of the glossopharyngeal nerve root. 4. The vasodilator response elicited by stimulation of the facial and glosso-pharyngeal nerves was never affected by lesion of the ipsilateral pterygopalatine ganglion. 5. Local anaesthesia or section of the inferior alveolar nerve abolished the vasodilator effects of stimulation of the facial and the glossopharyngeal nerves. 6. These results suggest that there is a somato-autonomic reflex vasodilator system mediated via final neurons that are not cholinergic, and that the parasympathetic vasodilator fibres emerge from the brain stem with the glossopharyngeal nerve and reach the blood vessels via the otic ganglion and the inferior alveolar nerve in the cat mandibular lip.

Animals↗
PubMed1992

Axon reflex flare evoked by nicotine in human skin.

(1) The purpose of the present study is to investigate whether or not the vasodilatation evoked by intradermal (I.D.) injection of nicotine is mediated through axon reflex mechanism, and to examine the involvement of histamine receptors or capsaicin-sensitive C-fibers in nicotine-induced vasodilator response, using a band method and a laser Doppler technique. (2) The vasodilator response, whether it was caused by nicotine or histamine, developed as quickly on the uninjected side as on the injected side of the band, while the wheal reaction was elicited only by histamine and was localized in the injection side of the band. (3) Pretreatment with either a local anesthetic (lidocaine) or 1% capasaicin markedly reduced the nicotine- and histamine-induced blood flow responses, whereas pretreatment with antihistaminergic agent (diphenhydramine) showed inhibitory effect to the blood flow response only to histamine. (4) These data suggest that two types of chemical receptors, i.e. the nicotinic and the histamine-sensitive receptors, exist in capsaicin-sensitive C-fibers to elicit axon reflex vasodilatation in human skin.

Adult↗
PubMed1992

[Evaluation of renal function with dynamic Gd-DTPA-enhanced magnetic resonance imaging after shock wave lithotripsy].

It has already been reported that MR imaging is a superior imaging technique to detect minute anatomical changes in the kidney after ESWL. However, the morphological abnormalities found by MR imaging do not necessarily mean deterioration of the renal function. The purpose of this study is to assess the morphological changes in the kidney and changes in renal function after the ESWL treatment by dynamic MR imaging. A total of 16 patients underwent axial MR imaging before and after ESWL. Dynamic MR was also performed on 11 patients of them within 24 hours after ESWL, and both before and after ESWL in the remaining 5 patients. Eight kidneys showed morphological abnormalities on T1-weight images, and 4 of them showed loss of corticomedullary demarcation. Furthermore, the first MR imaging after injection of GdDTPA revealed focal areas of decreased signal intensity in only 2 of these 4 patients who showed loss of corticomedullary demarcation on previous MR images. However, the second MR imaging 6 months after ESWL showed no abnormality in either of them. The percent contrast of signal intensity increase to fat signal intensity was one minute after GdDTPA injection compared before and after ESWL in 5 of the 16 patients. The values before and after ESWL revealed no statistically significant difference, and no patient showed any remarkable decrease of signal intensity after ESWL. These results suggest that loss of corticomedullary demarcation after ESWL does not necessarily reflect damage to the renal function and that the shock-wave exposure causes no permanent damage to the renal function but only temporary impairment.

Gadolinium DTPA↗
PubMed1992

[Pure yolk sac tumor of the testis with brain metastasis: report of an adult case].

Herein we report an adult case of pure yolk sac tumor with brain metastasis. The patient was a 37-year-old male who presented with indulation of his left scrotum for 10 months. The plain computerized tomographic (CT) scan on entry demonstrated tumor metastasis to his lung and liver and serum alpha-fetoprotein (AFP) level was 786 ng/ml. Five days after admission, he developed hemiplegia secondary to the cerebral metastasis and hemorrhage. After chemotherapy and operation of right-posterior lobectomy, PVB (cisplatinum, vinblastine, bleomycin) chemotherapy produced a complete remission and the elevated serum AFP was normalized. However, the second course of chemotherapy had to be discontinued because of drug-induced hepatitis. He died of massive tumor metastasis to his brain 6 months after craniotomy.

Adult↗
PubMed1992

Action of a novel kinin precursor, Met-T-kinin-Leu, on prostaglandin I2 and blood pressure.

The novel kinin precursor, Met-T-kinin-Leu, stimulated the release of prostaglandin I2 from endothelial cells cultured using bovine carotid artery endothelial cells and minimum essential medium supplemented with 10% fetal calf serum. However, it failed to stimulate the release of prostaglandin I2 from the cells in the fetal calf serum-free medium conditions. To examine the discrepancy of the release of prostaglandin I2 from the cells by Met-T-kinin-Leu in the presence or absence of fetal calf serum, the products formed from Met-T-kinin-Leu by incubation of culture medium were analyzed by reverse-phase HPLC. Regarding the blood pressure reaction of Met-T-kinin-Leu, it showed from one fifth to one hundredth of that compared with bradykinin in blood pressure reactivity of each species, such as rats, rabbits and cats.

Animals↗
PubMed1992

[Perioperative management for type A acute aortic dissection].

Twenty nine cases of type A acute aortic dissection were subjected to a retrospective study concerning perioperative management. Two keys pointed out for the management were as follow; (1) An optimal control of blood pressure is the most important measure to avoid advance of aortic dissection or rupture of dissecting aneurysm. Both pericardiac tamponade and aortic valve insufficiency should be taken care of from their onset, since they are often complicated after aortic dissections and their onset is fatal. (2) Separated brain perfusion and profound hypothermia with total circulatory arrest might involve a high risk of inducing postoperative brain damage and mortality, especially for old patients.

Acute Disease↗
PubMed1991

Vasodilator responses following intracranial stimulation of the trigeminal, facial and glossopharyngeal nerves in the cat gingiva.

The effects of electrical stimulation of the trigeminal, facial and glossopharyngeal nerves on gingival blood flow in the cat were studied. The intracranial part of these nerves was stimulated electrically, and gingival blood flow was measured by the laser Doppler technique. Electrical stimulation of the trigeminal, facial and glossopharyngeal nerves caused blood flow to increase in the ipsilateral gingiva both with the cranial nerve intact and after cutting it to the medulla. Stimulation of the distal cut ends of the facial and glossopharyngeal nerves elicited an increase in blood flow but no increase in systemic blood pressure. Pretreatment with hexamethonium reduced the increase in blood flow elicited by electrical stimulation of the facial and glossopharyngeal nerves, but had no effect on that elicited by stimulation of the trigeminal nerve. In contrast, pretreatment with tripelennamine attenuated the trigeminal nerve-stimulated blood flow increase, but not that elicited by stimulation of the facial and glossopharyngeal nerves. Atropine, propranolol and phentolamine had no effect on these responses. These results suggest that the autonomic nervous system, particularly the parasympathetic nervous system, is responsible for the blood flow increase elicited by facial and glossopharyngeal nerve stimulation, and that the trigeminal nerve-stimulated blood flow increase is induced by antidromic vasodilatation of the trigeminal sensory nerve.

Animals↗
PubMed1991

The distribution of IgG subclass autoantibodies in bullous pemphigoid analysed by immunofluorescence and immunoblotting.

The distribution of IgG subclasses in bullous pemphigoid (BP) autoantibodies in 14 BP sera and four biopsies was analysed by immunofluorescence (IF) and immunoblotting (IB). Three clones of monoclonal antibodies (MoAbs) to each IgG subclass were used. All 14 sera showed linear fluorescence in the basement membrane zone with IF, and 240 kDa and/or 180 kDa protein bands in human epidermal extract were detected by IB using a polyclonal antibody to total IgG. BP antibody in IgG4 subclass was found to be predominant, as it was detected most frequently and intensively in all positive sera and lesions studied by both techniques. In the IgG1 to IgG3 subclasses, a range of proportions of positive sera was obtained among MoAbs to the same IgG subclass in both techniques. However, one MoAb could detect IgG1 subclass BP antibody with a high frequency in both techniques. No difference in IgG subclass distribution of BP antibodies was observed during the course of the disease. In each serum, any IgG subclass of BP antibody recognized the identical BP antigen(s). These results suggest the predominance of IgG4 subclass and the possible presence of IgG1 subclass in BP antibodies.

Aged↗
PubMed1991

Platelet-activating factor stimulates production of prostaglandin E2 in murine osteoblast-like cell line MC3T3-E1.

We found that platelet-activating factor (PAF) stimulated the production of prostaglandin (PG) E2 in MC3T3-E1 cells in a time- and dose-dependent manner. 1.0 microM PAF gave a maximal stimulation of PGE2 production by MC3T3-E1 cells after a 4 hr PAF-treatment. Furthermore, the PAF-induced PGE2 production was abolished by the pre-treatment of the cells with a PAF receptor antagonist, 1-O-hexadecyl-2-acetyl-sn-glycero-3-phospho(N,N,N-trimethyl)hexanolamine, which occupied the same receptor site as PAF. These results suggest that PAF stimulates the PGE2 synthesis through a PAF receptor mediated pathway. Possibly PAF modulates bone metabolism by stimulating PGE2 synthesis.

Animals↗
PubMed1991

Prior bleeding enhances the sensitivity of the in vivo micronucleus test.

It has been reported that the sensitivity of the in vivo mouse bone marrow micronucleus test can be increased by inducing erythropoiesis with exogenous erythropoietin prior to treatment (Suzuki et al., 1989). In these studies we demonstrate that removing approximately 0.5 ml of blood from an adult male BDF1 mouse, another method for increasing the rate of erythropoiesis, synergistically increased the frequency of bone marrow micronucleated polychromatic erythrocytes induced by mitomycin C, with maximal enhancement occurring when the mutagen was given 24 h after bleeding. This enhancement response was also demonstrated for benzo[a]pyrene and dimethylnitrosamine but not for 2-acetylaminofluorene. These results indicate that bleeding mice prior to chemical treatment is a simple method for increasing the sensitivity of the micronucleus assay.

Animals↗