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Biomedical subjects

H Kanazawa

Publications and source records attributed to H Kanazawa.

At least 163 records · Page 9Linked to original sources
PubMed1993

Determination of acidic saponins in crude drugs by high-performance liquid chromatography on octadecylsilyl porous glass.

High-performance liquid chromatographic (HPLC) analysis on octadecylsilyl porous glass was investigated for acidic saponins in ginseng, bupleurum root and senega. The acidic saponins, malonyl-ginsenosides, malonyl-saikosaponins and senegins, as well as neutral saponins in the crude drugs were separated rapidly by HPLC on this column with aqueous acetonitrile containing KH2PO4 as the mobile phase at room temperature.

Carbohydrate Sequence↗
PubMed1993

Comparison of portal pressure with intravascular esophageal variceal pressure (IEVP) directly measured with a flexible indwelling needle.

Intravascular esophageal variceal pressure (IEVP) was measured using a flexible indwelling needle and compared with wedged hepatic venous pressure (WHVP) in 38 patients with liver cirrhosis. There was a high correlation between IEVP and WHVP; the former was lower than the latter, indicating the presence of a pressure gradient. Bleeders with a history of esophageal variceal rupture showed higher IEVP value than non-bleeders without a history of rupture, even though no difference in WHVP was observed. IEVP in the post-endoscopic injection sclerotherapy (EIS) group, even in those with endoscopic findings of large varices, was lower than that in the untreated groups. These results suggest that IEVP is a factor in the hemodynamics of patients with portal hypertension and that its measurement may be helpful in elucidating the pathophysiology of esophageal varices.

Blood Pressure Determination↗
PubMed1993

Extracorporeal membrane oxygenation for severe heart failure after Fontan operation.

A 10-year-old boy with tricuspid atresia and Glenn anastomosis underwent a modified Fontan operation. After the operation, the pressure in the inferior vena cava increased, leading to oliguria and ascites. After the creation of continuity between the superior vena cava and the inferior vena cava to reduce the pressure gradient, there remained an elevated right atrial pressure. Six days of extracorporeal membrane oxygenation effectively stabilized his hemodynamics and organ function and allowed an excellent outcome.

Angiography↗
PubMed1993

Effect of neuropeptide Y on human bronchus and its modulation of neutral endopeptidase.

BACKGROUND: Neuropeptide Y (NPY) and neutral endopeptidase have been shown to regulate the response of airway smooth muscle. However, their interactions have not been studied. METHODS: To determine the role of NPY and endogenous neutral endopeptidase in regulating the effects of NPY, we investigated the effects of NPY and a neutral endopeptidase inhibitor, phosphoramidon, on the contractile response of isolated human bronchial segments to electrical field stimulation (EFS). RESULTS: Concentrations of up to 10(-6) mol/L of NPY did not change resting tension. NPY inhibited the cholinergic contractions induced by EFS at 5 Hz dose-dependently. Phosphoramidon (10(-5) mol/L) enhanced the inhibitory effect of NPY on EFS-induced contractions at 5 Hz. NPY (3 x 10(-7) mol/L) shifted the frequency-response curve for EFS (1 to 50 Hz) to the right and significantly increased the mean logarithm of frequency that produced 50% of maximal contraction (control: 0.54 +/- 0.07 versus NPY: 0.79 +/- 0.09, p < 0.05). Phosphoramidon (10(-5) mol/L) did not affect the frequency response to EFS, but enhanced the inhibitory effect of NPY (3 x 10(-7) mol/L) on frequency response to EFS, resulting in a significant increase in the mean logarithm of frequency that produced 50% of maximal contraction (NPY: 0.79 +/- 0.09 versus NPY plus phosphoramidon: 1.18 +/- 0.15, p < 0.05). NPY (3 x 10(-7) mol/L) did not affect the response of tissues to exogenously applied acetylcholine. CONCLUSIONS: These observations suggest that NPY inhibits the output of acetylcholine from nerve endings and that endogenous neutral endopeptidase modulates the effect of NPY in the human airway by inactivating this peptide.

Acetylcholine↗
PubMed1993

Effect of a new leukotriene receptor antagonist, ONO-1078, on human bronchial smooth muscle in vitro.

Peptide leukotrienes (LT) have been postulated to play a major role in the etiology of bronchial asthma. The present study investigated the effect of a new peptide LT receptor antagonist, ONO-1078, on isolated human bronchial smooth muscle in vitro. Helical strips of bronchi were suspended in the organ baths filled with 37 degrees C Krebs solution and mechanical responses were recorded isometrically. ONO-1078 produced dose-dependent relaxations, which suggested that the spontaneous basal tone was in part mediated by LT. ONO-1078 caused dose-dependent relaxations of the tissues which were precontracted with LTC4 or LTD4 (3 x 10(-8) M). Pretreatment of bronchi with ONO-1078 (10(-8) M, 10(-7) M) significantly inhibited dose-dependent contractions induced by LTC4 and LTD4. ONO-1078 (10(-6) M) also significantly reduced the antigen-induced contractions in bronchi passively sensitized with atopic serum from mite-allergic patients. Moreover the combination of an H1-receptor antagonist, diphenhydramine (10(-5) M), and ONO-1078 (10(-6) M) completely abolished the antigen-induced contractions. The present findings demonstrate that ONO-1078 is a potent antagonist of exogenous and endogenous LT in the human airway. The selective LT antagonist such as ONO-1078 may be valuable in the therapy of allergic asthma.

Aged↗
PubMed1993

Solitary plasmacytoma of the mandible. Case report and review of the literature.

A case of solitary plasmacytoma of the mandible is presented. Review of the literature disclosed the following characteristics regarding the clinical course and prognosis. The patients ages ranged from 34 to 76 years, with a mean of 53 years; there was a marked preponderance of males. The site of predilection was the posterior portion of the mandible. The common symptom was a non-painful swelling of the mandible of long duration, and radiological features were non-specific. Monoclonal immunoglobulin was initially detected in 42% of the evaluated patients. The majority of patients were treated with radiation therapy with a mean dose of 48Gy with or without surgery. The period of follow-up ranged from 4 months to 12 years, and 17% of the patients progressed to multiple myeloma within 1 year.

Female↗
PubMed1993

Site-specific inactivation of papain by ascorbic acid in the presence of cupric ions.

The mechanism of inactivation of papain (EC 3.4.22.2) by ascorbic acid (AsA) in the presence of cupric ions (Cu2+) was investigated. The aerobic combination of Cu2+ and AsA resulted in an irreversible loss of enzyme activity. The inactivation was found to be an apparent first order reaction. The prior mixing of Cu2+ and AsA caused the complete disappearance of the inactivation. The addition of iron ions led to significant suppression against the inactivation. Cu2+ was bound to the enzyme in a molar ratio of 1:1. At lower concentrations of Cu2+ (molar ratio of enzyme to Cu2+ of 1: < 1), the extent of inactivation showed the same dependence against the extent of oxidation of AsA. The rate of inactivation increased as the concentration of AsA was increased. Saturation kinetics were observed with respect to the concentration of AsA. Changes in the concentration of Cu2+ had no effect on the dissociation constant of the enzyme-AsA complex (KI), though the rate constant of inactivation (k2) showed a linear relationship with the concentration of Cu2+. At various pH values tested, no change of k2 was found, whereas the value of KI increased when the pH bacame lower. At higher concentrations of Cu2+, the rate of inactivation fell beyond a certain concentration of AsA. The present results suggest that both Cu2+ and AsA bind to the enzyme to form a ternary complex and that free radicals are site-specifically formed and react preferentially with the enzyme, at the site of their formation, impairing its activity.

Ascorbic Acid↗
PubMed1993

Met-enkephalin-Arg6-Gly7-Leu8-like immunoreactivity in mammalian taste buds.

Light-microscopic immunocytochemistry for various bioactive peptides including some gastroenteropancreatic hormones and a neuronal enzyme, neuron-specific enolase (NSE), was applied to taste buds in the circumvallate papillae of rats, mice and guinea pigs. In all the species positive immunoreactivities were demonstrated for Met-enkephalin-Arg6-Gly7-Leu8 (Met-Enk-8). The Met-Enk-8-like immunoreactivity was confined to parts of the spindle-shaped bud cells. These cells in rats and guinea pigs displayed a concomitant immunoreactivity for NSE. In the mouse taste buds, however, there appeared no such correlation between the immunoreactivities. Considering our previous data, the present finding supports a possibility that opioid peptide(s) derived from preproenkephalin A might be the transmitter(s) of the gustatory cell.

Animals↗
PubMed1993

Fine structure of the canine taste bud with special reference to gustatory cell functions.

Canine taste buds were observed by transmission electron microscopy with special reference to the gustatory cell function. The cells forming the taste bud were divided into five types: four of these corresponded to the previously reported Types I, II, III and IV (basal cell); another type, a slender, immature-looking cell located at the outermost layer, was identified as the peripheral cell known in the rat. The Type I cell was supportive in nature, located between other cell types and enveloping nerve fibers. This cell apically secretes dense mucous substances. The Type II cell was in broad contact with nerve fibers and constantly contained a subsurface cistern beneath them. In the dog, this cell was characterized by a large supranuclear Golgi apparatus. The Type III cell was, as in other animals, regarded as the gustatory cell since it made synaptic contacts with nerves and contained synaptic vesicles. Numerous large corded vesicles were intermingled with some small clear vesicles. In addition to accumulating to the synaptic areas, the vesicles often filled the base of the cell, which was irregularly thickened, showing a more or less extensive contact with the basement membrane. In this area, numerous large cored vesicles approached the cell base. Blood capillaries close to the base of the taste bud were fenestrated in the endothelium. These findings supported a hypothesis that the transmitters may be released from the base of the gustatory cell and possibly exert paracrine and endocrine (hemocrine) effects. The salivary gland of Ebner was suggested as one such target. The nerve terminals on the Type III cell also contained synaptic vesicles, suggesting a reciprocal nature of the synapses. The Type IV cell was the immature basal cell which has been established in other species; mitosis could be seen in this cell.

Animals↗
PubMed1993

Exocrinopathy resembling Sjögren's syndrome induced by a murine retrovirus.

BACKGROUND: Sjögren's syndrome (SS) is characterized by lymphocytic infiltration into, and destruction of exocrine glands, resulting in dryness of the mouth and eyes. The disease is considered to have an autoimmune etiology, however, its etiopathogenesis remains largely unknown. Recently, retrovirus is suggested to participate in the pathogenesis of SS, because SS-like lesions are reported in HIV infection or in human T cell leukemia virus type I infection. Moreover, human intracisternal A-type retroviral particles are reported to be detected in SS patients. During the course of our study on the histopathology of mice infected with a murine retrovirus, we happened to find SS-like exocrinopathy in those mice. EXPERIMENTAL DESIGN: Four-week-old C57BL/6 (B6) mice were injected intraperitoneally with LP-BM5 murine leukemia virus. This virus is known to induce splenomegaly, lymphadenopathy followed by lymphoid malignancy, and profound immunodeficiency in sensitive strains of mice. From 4 to 16 weeks after the virus inoculation, the infected mice were sacrificed and their submandibular and lacrimal glands were analyzed light and electron microscopically and immunohistochemically. The existence of the virus in the lesion in situ was also analyzed by the same method, and additionally by a polymerase chain reaction method. RESULTS: Periductal lymphocytic infiltration into the submandibular and lacrimal glands was observed in all the virus-infected mice at 4 weeks after the infection and progressed with time. Extraglandular lymphocytic infiltration was also observed in liver, kidney, lung, and pancreas. Immunohistochemical examination revealed that most infiltrating cells into the glands were composed of CD3+ T cells (CD4-dominant), Mac-1+ cells, and B220+ cells. The virus genome was detected in submandibular glands by immunohistochemistry or by polymerase chain reaction. In addition, retroviral particles were secreted into the lumen of exocrine ducts of submandibular glands. CONCLUSIONS: This might be an SS animal model that is induced by a certain defined retrovirus. This experimental system might provide us with valuable information for analyzing the mechanisms of how a retrovirus could induce SS.

Animals↗
PubMed1993

Hyporesponsiveness to inhibitory agents of alveolar macrophages and polymorphonuclear leukocytes primed by platelet activating factor.

In this study, it was presented that PAF and LTB4 exert a priming effect on PMNs to promote their superoxide anion production. PMNs preincubated with PAF of normal controls or PMNs from asthmatic patients are activated and their responsiveness to inhibitory stimuli such as antiallergic drugs and corticosteroid are attenuated. In conclusions, inflammatory cells of asthmatics may be activated by various mediators and play an important role in the progress of airway damage.

Adult↗
PubMed1993

[Propranolol for prophylaxis of first hemorrhage in cirrhotic patients with esophageal varices--a controlled study comparing with sclerotherapy].

To compare the efficacy of oral propranolol and sclerotherapy in the prevention of first hemorrhage from esophageal varices, 65 cirrhotic patients with moderate to large esophageal varices and no history of bleeding were included in the prospective controlled trial. After randomization, 33 patients received propranolol at a does reducing the heart rate by 25%; 32 patients were treated with intra-variceal and extra-variceal injection of ethanolamine oleate. On entry to the trial, the two groups were comparable in terms of clinical and biological parameters. The patients were observed for up to 60 months, with an average of 31 months. Nine patients bled (5 in propranolol and 4 in sclerotherapy) during follow-up. No significant difference were observed between propranolol and sclerotherapy in the cumulative bleeding rate and survival. The multivariate Cox model indicated that drug compliance in the propranolol group and high portal pressure in the sclerotherapy group were factors predictive of the first hemorrhage. These data support that propranolol and sclerotherapy are of comparable value in preventing the first hemorrhage in cirrhotic patients with esophageal varices.

Aged↗
PubMed1993

[Excellent late results of total circulatory annuloplasty with absorbable suture for the repair of mitral regurgitation of atrioventricular septal defects in children].

We treated 15 children with atrioventricular septal defects (6 complete type and 9 incomplete type) using total circulatory annuloplasty for mitral regurgitation. In 14 patients, total circulatory annuloplasty was performed with absorbable suture and in one patient with polypropylene suture. Operative death was one patient associated with tetralogy of Fallot and another 14 patients survived. Preoperative mitral regurgitation was grade 1 in one patient, grade 2 in 6 patients and grade 3 in 7 patients. After operation mitral regurgitation reduced to grade 1 in 13 patients and grade 2 in one patient. In the late results, only one patient underwent reoperation for exacerbation of mitral regurgitation. The present data suggested that total circulatory annuloplasty with absorbable suture was very useful technique for the repair of mitral regurgitation of atrioventricular septal defects in children.

Child↗
PubMed1992

Low concentration endothelin-1 enhanced histamine-mediated bronchial contractions of guinea pigs in vivo.

Endothelin-1 (ET-1) represents one of the most potent constrictors of guinea pig bronchial smooth muscle. In our study, various doses of aerosolized ET-1 increased airway resistance. But a very low concentration of ET-1 (10(-12) M) could not change airway resistance. We examined low doses of ET-1 enhanced the sensitivity of bronchial contractions to histamine. ET-1 may play one of the most important roles in contributing directly or indirectly to the pathogenesis of bronchial asthma.

Aerosols↗
PubMed1992

Mapping of antigenic sites to monoclonal antibodies on the primary structure of the F1-ATPase beta subunit from Escherichia coli: concealed amino-terminal region of the subunit in the F1.

To analyze relationships between the ternary and primary structures of the beta subunit of Escherichia coli F1 ATPase, we prepared two monoclonal antibodies beta 12 and beta 31 against the beta peptide. These antibodies bind to the beta subunit but do not bind to the F1 ATPase, resulting in no inhibition of the ATPase activities. Several different portions of the beta subunit peptide were prepared by constructing expression plasmids carrying the corresponding DNA segment of the beta subunit gene amplified by the polymerase chain reaction. Western blotting analysis using these peptides revealed that the antibodies bound to a peptide of 104 amino acid residues from the amino terminal end, which is outside the previously estimated catalytic domain between residues 140 and 350. These results indicated that the amino terminal portion of the maximal 104 residues is not exposed to the surface of the F1 ATPase. The binding spectrum of the antibodies to the subunit from various species including Vibrio alginolyticus and thermophilic bacterium PS3 indicated possible epitope sequences within the 104 residues. The ternary structure of the beta subunit, in terms of cleavage sites by endopeptidases, was analyzed using the antibodies. A 43-kDa peptide without binding ability to beta 12 and beta 31 appeared upon cleavage by lysyl endopeptidase. The results suggested that lysyl residues from around 70 to 100 from the amino terminus are exposed to the surface of the beta subunit.

Amino Acid Sequence↗