Biomedical subjects

H Matsuda

Publications and source records attributed to H Matsuda.

At least 991 records · Page 55Linked to original sources

PubMed1994

Utility of 123I-IMP SPECT brain scans for the early detection of site-specific abnormalities in Creutzfeldt-Jakob disease (Heidenhain type): a case study.

Serial changes in brain imaging of regional cerebral blood flow with single photon emission computed tomography (SPECT) using N-isopropyl-(iodine-123) p-iodoamphetamine (123I-IMP) were observed in a patient with probable Heidenhain type of Creutzfeldt-Jakob disease, which was characterized by the initial onset of visual symptoms. Corresponding to the visual signs and periodic synchronous discharges localized in the bilateral parietal and occipital regions on EEG, focal hypoperfusion images in the occipital lobes were detected on the SPECT scan before brain X-ray computed tomography and magnetic resonance imaging showed any abnormalities. These results suggest that SPECT brain imaging is useful in the early detection of site-specific abnormalities in Creutzfeldt-Jakob disease.

Aged↗

PubMed1994

Correlations between quantitative EEG and regional cerebral blood flow (SPECT) in patients with partial epilepsy.

During interictal periods in 9 patients with partial epilepsy we examined whether there were correlations between the relative power of background EEG (power spectral analysis) and the absolute values of regional cerebral blood flow (rCBF) measured by 99mTc hexamethylpropylene amine oxime (HMPAO) SPECT in each cerebral region. None of the patients had any organic cerebral lesions on X-ray CT examinations, neurological abnormalities or mental retardation. There was an inverse correlation between rCBF and the relative power of the theta band, and a direct correlation between rCBF and that of the alpha band of 10-12.8 Hz, in the right and/or left frontal, parietal and temporal regions. In the occipital regions, there was a direct correlation only between rCBF and the relative power of the beta band. These correlations were noted whether the analyzed regions were epileptic foci or not. These results suggest that background EEG and rCBF changes in epileptic patients are closely coupled.

Adult↗

PubMed1994

Neointima formation after vascular stent implantation. Spatial and chronological distribution of smooth muscle cell proliferation and phenotypic modulation.

Intravascular stents have proved useful as angioplasty devices, but intimal hyperplasia after stent implantation remains an unsolved problem. In the present study, we analyzed the spatial and chronological distribution of proliferation and phenotypes of smooth muscle cells (SMCs) in rabbit aortas during the process of neointima formation after stent implantation (Gianturco's Z type) by immunohistochemistry for proliferating cell nuclear antigen (PCNA) and myosin heavy chain isoforms (SM1, SM2, and SMemb). Stent implantation induced regional injury in the arterial wall. Medial SMCs then began to proliferate adjacent to the injured SMCs, maximally on day 4 (PCNA index in the media: 3.9 +/- 3.4% [mean +/- SD]), and were modulated to the embryonic phenotype (SMemb-positive and SM2-negative). They migrated into the intima and proliferated most frequently on day 7 (PCNA index in the intima: 20.3 +/- 5.5%) and subsequently led to fibrocellular neointima formation at 2 weeks and later. At 1 month after implantation and later, SMC proliferation was rare, and the phenotype of intimal SMCs was gradually returning to the adult type (SMemb-negative and SM2-positive). Thus, this stent implantation model demonstrates that the regional effect on arterial wall by stenting leads to neointima formation through transient and regional proliferation and migration of SMCs and their phenotypic modulations.

Animals↗

PubMed1994

Studies on rehmanniae radix. I. Effect of 50% ethanolic extract from steamed and dried rehmanniae radix on hemorheology in arthritic and thrombosic rats.

Effects of 50% ethanolic extract (JR-ext) from Chinese Rehmanniae Radix (the steamed and dried root of Rehmannia glutinosa, "Jyuku-Jio" in Japanese) on the hemorheology of inflammatory, thrombosic and intact animals were examined in the in vivo models. JR-ext (200 mg/kg, p.o.) inhibited the reduction of fibrinolytic activity and erythrocyte deformability, the decrease in erythrocyte counts and the increase in connective tissue of the thoracic artery in a chronic inflammatory model, adjuvant-induced arthritis. However, JR-ext was ineffective on the development of edema in the arthritic rats and on acute and chronic inflammation. JR-ext inhibited the reduction of erythrocyte deformability, but not the decrease of coagulative factors in a thrombosic model, endotoxin-induced disseminated intravascular coagulation (DIC). JR-ext also showed a promoting effect on erythrocyte deformability and fibrinolytic activity in intact rats. These results suggest that orally administered JR-ext can prevent an inducement of impediment in the peripheral microcirculation of various chronic diseases through the improvement of hemorheology.

Acetates↗

PubMed1994

Studies of cuticle drugs from natural sources. II. Inhibitory effects of Prunus plants on melanin biosynthesis.

The inhibitory effects of 50% ethanolic extracts from dried leaves of 38 plants collected in the herbal garden of Kinki University were investigated in vitro on melanin biosynthesis which is closely related to hyperpigmentation. Of the 38 extracts, Prunus yedoensis, P. zippeliana, P. amygdalus, P. persica, P. armeniaca, Thea sinensis and Chaenomeles sinensis showed a potent inhibition of tyrosinase, the enzyme which converts 3-(3,4-dihydroxyphenyl)alanine (dopa) to dopachrome in the biosynthetic process. Furthermore, the extracts from the leaves of P. yedoensis and P. zippeliana among the Prunus plants used in this experiment inhibited the production of melanin from dopachrome by autoxidation. These inhibitory effects of P. zippeliana on melanin biosynthesis were observed in cultured B-16 mouse melanoma cells. These results suggest that the leaves of P. zippeliana inhibit melanin biosynthesis which is involved in hyperpigmentation and could be used as a whitening agent for the skin.

Animals↗

PubMed1994

Study of various rhubarbs regarding the cathartic effect and endotoxin-induced disseminated intravascular coagulation.

Sennoside A content in hot-water extracts from 17 varieties of rhubarb obtained from the market was measured, and their respective cathartic effects were also examined in mice. A positive correlation was confirmed between the sennoside A content and cathartic effects in our experiments. Furthermore, the effects of Shisendaio [symbol: see text], with a higher sennoside A content, and Kinmondaio [symbol: see text], with a lower sennoside A content, exhibited endotoxin-induced disseminated intravascular coagulation (DIC) which related closely to Oketsu symptoms, and these effects were examined in rats. Kinmondaio exhibited weak inhibition on both reducing erythrocyte deformability and prolonging euglobulin lysis time (ELT) in DIC rats. From our results, it is possible to evaluate rhubarb's cathartic effect, one of its main drug effects, by examining the rhubarb's sennoside A content. However, it is difficult to estimate the cathartic effect according to the general market name of Rhubarb. No dramatic effect was found on the experimental models used for Oketsu symptoms such as endotoxin-induced DIC.

Administration, Oral↗

PubMed1994

Anti-inflammatory activities of methanolic extract and alkaloidal components from Corydalis tuber.

A methanolic extract (CM-ext) from Corydalis tuber (Corydalis turtschaninovii Besser forma yanhusuo Y. H. Chou et C. C. Hsu) has been screened for activity in experimental models of inflammation. CM-ext (200 or 500 mg/kg, p.o.) inhibited an increase in vascular permeability in mice induced by acetic acid, and reduced acute paw edema in rats induced by compound 48/80 or carrageenin. CM-ext suppressed the development of adjuvant-induced edema in arthritic rats. CM-ext and its alkaloidal components, dehydrocorydaline, d-glaucine and l-tetrahydrocoptisine inhibited compound 48/80-induced histamine release from peritoneal mast cells of rats. Since these substances from C. tuber were found to be effective in both the acute and chronic phases of inflammation, the crude drug C. tuber can be considered to exert anti-inflammatory activity.

Alkaloids↗

PubMed1994

Studies of anti-cataract drugs from natural sources. I. Effects of a methanolic extract and the alkaloidal components from Corydalis tuber on in vitro aldose reductase activity.

The inhibitory of Corydalis tuber (Corydalis turtschaninovii Besser forma yanhusuo Y. H. Chou et C. C. Hsu) was tested on crude rat lens aldose reductase, an enzyme involved in the complications of diabetes. The methanolic extract (CM-ext) inhibited aldose reductase, while the aqueous extract (CA-ext) was ineffective. Only dehydrocorydaline, of the seven alkaloidal components isolated from CM-ext, inhibited aldose reductase. It is suggested that the inhibitory effect of CM-ext on aldose reductase may be partially attributed to dehydrocorydaline.

Aldehyde Reductase↗

PubMed1994

Stomachic principles in ginger. III. An anti-ulcer principle, 6-gingesulfonic acid, and three monoacyldigalactosylglycerols, gingerglycolipids A, B, and C, from Zingiberis Rhizoma originating in Taiwan.

An anti-ulcer constituent, 6-gingesulfonic acid, and three monoacyldigalactosylglycerols, gingerglycolipids A, B, and C, were isolated from Zingiberis Rhizoma, the dried rhizome of Zingiber officinale Roscoe which was cultivated in Taiwan, together with (+)-angelicoidenol-2-O-beta-D-glucopyranoside. Based on chemical reactions and physicochemical evidence, the structures of 6-gingesulfonic acid, gingerglycolipids A, B, and C have been determined. In addition, the absolute stereostructure of (+)-angelicoidenol-2-O-beta-D-glucopyranoside was clarified on the basis of its synthesis from d-borneol. 6-Ginesulfonic acid showed weaker pungency and more potent anti-ulcer activity than 6-gingerol and 6-shogaol.

Animals↗

PubMed1994

Elatoside E, a new hypoglycemic principle from the root cortex of Aralia elata Seem.: structure-related hypoglycemic activity of oleanolic acid glycosides.

A new inhibitor named elatosides E (which was shown to affect the elevation of plasma glucose level by oral sugar tolerance test in rats) was isolated from the root cortex of Aralia elata Seem. together with elatoside F. The structures of elatosides E and F were elucidated on the basis of chemical and physicochemical evidence. The hypoglycemic activities of oleanolic acid and nine oleanolic acid glycosides obtained from the root cortex of Aralia elata have been examined, and some structure-activity relationships have been found.

Animals↗

PubMed1994

Escins-Ia, Ib, IIa, IIb, and IIIa, bioactive triterpene oligoglycosides from the seeds of Aesculus hippocastanum L.: their inhibitory effects on ethanol absorption and hypoglycemic activity on glucose tolerance test.

Five triterpene oligoglycosides named escins-Ia, Ib, IIa, IIb, and IIIa were isolated from the seeds of Aesculus hippocastanum L. and their chemical structures were determined on the basis of chemical and physicochemical evidence. Escins-Ia, Ib, IIa, and IIb were found to exhibit inhibitory effect on ethanol absorption and hypoglycemic activity on oral glucose tolerance test in rats. Among them, escins-IIa and IIb showed the higher activities for both bioassays, while desacylescins-I and II had no activity.

Animals↗

PubMed1994

Absolute stereostructures of hydramacrosides A and B, new bioactive secoiridoid glucoside complexes from the leaves of Hydrangea macrophylla Seringe var. thunbergii Makino.

Two new bioactive secoiridoid glucoside complexes named hydramacrosides A and B were isolated from the leaves of Hydrangea macrophylla SERINGE var. thunbergii MAKINO. The absolute stereostructures of hydramacrosides A and B were elucidated on the basis of chemical and physicochemical evidence which included the application of the 13C NMR glycosylation shift rule of 1, 1'-disaccharides and the modified Mosher's method. Hydramacrosides A and B exhibited inhibitory effect on the histamine release from rat mast cells induced by antigen-antibody reaction.

Animals↗

PubMed1994

Crude drugs from aquatic plants. IV. On the constituents of alismatis rhizoma. (2). Stereostructures of bioactive sesquiterpenes, alismol, alismoxide, orientalols A, B, and C, from Chinese alismatis rhizoma.

Following the characterization of the triterpene constituents in Chinese Alismatis Rhizoma, we investigated the chemical structures of orientalols A, B, and C, isolated from the less polar fraction of the crude drug together with two known sesquiterpenes, alismol and alismoxide. On the basis of the chemical and physicochemical evidence, the structures of orientalols A, B, and C have been determined and those of alismol and alismoxide were revised. All five sesquiterpenes were found to show an inhibitory effect on the contraction of isolated bladder smooth muscle induced by carbachol.

Animals↗

PubMed1994

Synthesis and structure-activity relationships of antiallergic N-[4-[4-(1H-indol-3-yl)piperidinoalkyl]-2-thiazolyl]alkanamides possessing both antihistaminic and anti slow-reacting substance (SRS) activities.

A series of N-[4-[4-(1H-indol-3-yl)piperidinoalkyl]-2- thiazolyl]alkanamide derivatives were synthesized and tested for in vivo antianaphylactic activity and in vitro anti slow-reacting substance (SRS) activity. Among the compounds synthesized, N-[4-[4-(1H-indol-3-yl)piperidinomethyl]-2- thiazolyl]propanamide (7) was the best balanced compound (antianaphylactic activity, ED50 = 0.92 mg/kg p.o.; anti-SRS activity, IC50 = 0.89 microgram/ml). Regarding the biological activities of 7, we ascribe the antianaphylactic activity to its potent antihistaminic activity and the anti SRS activity to the inhibition of 5-lipoxygenase.

Amides↗

PubMed1994

Development of bioactive functions in hydrangeae dulcis folium. III. On the antiallergic and antimicrobial principles of hydrangeae dulcis folium. (1). Thunberginols A, B, and F.

From the less polar fraction of Hydrangeae Dulcis Folium, the fermented and dried leaves of Hydrangea macrophylla Seringe var. thunbergii Makino, Eight antiallergic and antimicrobial principles were isolated together with several known compounds. Among the newly isolated bioactive constituents, the chemical structures of thunberginols A, B, and F have been determined on the basis of chemical and physicochemical evidence. Thunberginols A, B, and F were found to exhibit more potent antiallergic activity than phyllodulcin, hydrangenol, disodium cromoglycate (DSCG), and tranilast. In addition, these thunberginols showed antimicrobial activity against oral bacteria.

Animals↗

PubMed1994

Crude drugs from aquatic plants. V. On the constituents of alismatis rhizoma. (3). Stereostructures of water-soluble bioactive sesquiterpenes, sulfoorientalols a, b, c, and d, from Chinese alismatis rhizoma.

From the water-soluble portion of Chinese Alismatis Rhizoma, four bioactive sesquiterpenes, sulfoorientalols a, b, c, and d, were isolated and their structures having a sulfonic acid function were established on the basis of chemical and physicochemical evidence. In addition, two sulfoorientalol congeners were derived from alismol by sulfonation of the exo-methylene moiety. Sulfoorientalols and the synthetic congeners were found to inhibit the carbachol-induced contraction of isolated bladder smooth muscle of guinea pig.

Animals↗

PubMed1994

Camelliasaponins B1, B2, C1 and C2, new type inhibitors of ethanol absorption in rats from the seeds of Camellia japonica L.

New type inhibitors of ethanol absorption, camelliasaponins B1, B2, C1 and C2, were isolated from the seeds of Camellia japonica L. The structures of camelliasaponins were elucidated on the basis of chemical and physicochemical evidence. The inhibitory effect of camelliasaponins and related saponins on ethanol absorption have been examined, and it was found that the triterpene oligoglycoside structure having an acyl group was essential to exerting the activity.

Animals↗

PubMed1994

[Crude drugs from aquatic plants. III. Quantitative analysis of triterpene constituents in alismatis rhizoma by means of high performance liquid chromatography on the chemical change of the constituents during alismatis rhizoma processing].

As a series of study on the evaluation of Alismatis Rhizoma and the chemical characterization of the processing, a quantitative method by high performance liquid chromatography (HPLC) for ten triterpene constituents, alisols A, A monoacetate, B, B monoacetate, E 23-acetate, F, and G and 13,17-epoxyalisol A, 11-deoxyalisols B and B 23-acetate, has been developed. By the use of this HPLC method, the contents of these triterpenes in various Alismatis Rhizoma and the fresh rhizoma of Alisma oriental JUZEPC, originated from in China, Taiwan, and Japan were examined. Furthermore, the chemical change of the triterpene constituents during the drying process of the rhizoma of Alisma oriental has been investigated and it was found that the bioactive triterpenes of Alismatis Rhizoma such as alisol A and alisol A monoacetate were artificially formed during the drying process.

Chromatography, High Pressure Liquid↗