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Biomedical subjects

M Yoshikawa

Publications and source records attributed to M Yoshikawa.

At least 271 records · Page 15Linked to original sources
PubMed1998

Structures of new acylated oleanene-type triterpene oligoglycosides, theasaponins E1 and E2, from the seeds of tea plant, Camellia sinensis (L.) O. Kuntze.

Two new acylated oleanene-type triterpene oligoglycosides, theasaponins E1 and E2, were isolated from the seeds of tea plant [Camellia sinensis (L.) O. Kuntze]. The structures of theasaponins E1 and E2 were elucidated on the basis of chemical and physicochemical evidence to be expressed as 21-O-angeloyl-22-O-acetyltheasapogenol E 3-O-[beta-D-galactopyranosyl(1-->2])[beta-D-xylopyranosyl(1-->2)-alpha-L - arabinopyranosyl (1-->3)]-beta-D-glucopyranosiduronic acid and 21-O-angeloyl-28-O-acetyltheasapogenol E 3-O-[beta-D-galactopyranosyl(1-->2)][beta-D-xylopyranosyl (1-->2)-alpha-L-arabinopyranosyl (1-->3)-beta-D-glucopyranosiduronic acid, respectively. Theasaponin E1 was found to show antisweet activity.

Acylation↗
PubMed1998

Bioactive saponins and glycosides. XI. Structures of new dammarane-type triterpene oligoglycosides, quinquenosides I, II, III, IV, and V, from American ginseng, the roots of Panax quinquefolium L.

The methanolic extract and 1-butanol-soluble fraction of American ginseng, the roots of Panax quinquefolium L., were found to exhibit a protective effect on liver injury induced by D-galactosamine and lipopolysaccharide. Five new dammarane-type triterpene oligoglycosides called quinquenosides I, II, III, IV, and V were isolated together with fourteen known dammarane-type triterpene oligoglycosides such as chikusetsusaponin IVa, pseudo-ginsenoside-RC1, malonyl-ginsenoside-Rb1, and notoginsenosides-A,-C, and -K from the 1-butanol-soluble fraction. From the ethyl acetate-soluble fraction, four known acetylenic compounds and 6'-O-acetyl ginsenoside-Rg1 were isolated. The structures of quinquenosides I, II, III, IV, and V were determined on the basis of chemical and physicochemical evidence as 3-O-[6-O-(E)-2-butenoyl-beta-D-glucopyranosyl(1-->2)-beta-D- glucopyranosyl]-20-O-(beta-D-glucopyranosyl) 20(S)-protopanaxadiol (quinquenoside I), 3-O-[6-O-(E)-2-octenoyl-beta-D- glucopyranosyl(1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl] 20(S)-protopanaxadiol (quinquenoside II), 3-O-[beta-D-glucopyranosyl (1-->2)-6-O-acetyl-beta-D-glucopyranosyl]-20-O-(beta-D-glucopyranosyl) 20(S)-protopanaxadiol (quinquenoside III), 3-O-[beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl]-20-O-beta-D- glucopyranosyl(1-->6)-beta-D-glucopyranosyl]-3 beta, 7 beta, 20(S)-trihydroxydammar-5,24-diene (quinquenoside IV), and 3-O-[beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl]-20-O-[alpha-D- glucopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranosyl ] 20(S)-protopanaxadiol (quinquenoside V).

Animals↗
PubMed1998

Medicinal foodstuffs. XII. Saponin constituents with adjuvant activity from hyacinth bean, the seeds of Dolichos lablab L. (1): Structures of lablabosides A, B, and C.

From the glycoside mixture with adjuvant activity obtained from the hyacinth bean, the seeds of Dolichos lablab L., six new oleanane-type triterpene bisdesmosides, lablabosides A, B, C, D, E, and F, were isolated together with chikusetsusaponin IVa. The structures of lablabosides A, B, and C were determined on the basis of chemical and physicochemical evidence as follows: 3-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-galactopyranosyl (1-->2)-beta-D-glucopyranosiduronic acid]-28-O-(beta-D-glucopyranosyl) oleanolic acid (lablaboside A), 3-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-galactopyranosyl (1-->2)-beta-D-glucopyranosiduronic acid]-28-O-(beta-D-glucopyranosyl) 24-epi-hederagenin (lablaboside B), 3-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D- galactopyranosyl (1-->2)-beta-D-glucopyranosiduronic acid]-28-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-glucopyranosyl] 24-epi-hederagenin (lablaboside C).

Adjuvants, Immunologic↗
PubMed1998

Novel indole S,O-bisdesmoside, calanthoside, the precursor glycoside of tryptanthrin, indirubin, and isatin, with increasing skin blood flow promoting effects, from two Calanthe species (Orchidaceae).

The methanolic extracts from Calanthe discolor LINDL. and C. liukiuensis SCHLTR. were found to exhibit hair restoring and skin blood flow promoting activities. Through bioassay-guided separation using the skin blood flow increasing effect, a novel indole S,O-bisdesmoside, calanthoside, was isolated together with three new components, glucoindican, calaliukiuenoside, and calaphenanthrenol, and known compounds such as tryptanthrin, indirubin, isatin, and indican. The structures of the new compounds were determined on the basis of physicochemical and chemical evidence and they showed an activating effect on skin blood flow. In addition, it was found that enzymatic hydrolysis of calanthoside with beta-glucosidase furnished tryptanthrin together with a small amount of indirubin and isatin, whereas indirubin and isatin were obtained from calanthoside by acid hydrolysis. Based on their contents in the fresh and dried plant, calanthoside may be a common genuine glycoside of tryptanthrin, indirubin, and isatin in the plant.

Animals↗
PubMed1998

[Medicinal foodstuffs. XI. Histamine release inhibitors from wax gourd, the fruits of Benincasa hispida Cogn].

The methanol extract of wax gourd (Japanese name "Tougan"), the fruits of Benincasa hispida COGN. (Cucurbitaceae), was found to show inhibitory activity on the histamine release from rat exudate cells induced by antigen-antibody reaction. Through bioassay-guided separation, four known triterpenes and two known sterols were isolated as active components together with a flavonoid C-glycoside, an acylated glucose, and a benzyl glycoside. Among the active triterpenes and sterols, two triterpenes, alnusenol and multiflorenol, were found to potently inhibit the histamine release.

Animals↗
PubMed1998

Dose-dependent effects of dichloropropanol on liver histology and lipid peroxidation in rats.

A rare outbreak of acute hepatic damage in workers exposed to dichloropropanols (DCPs) was reported recently. The purpose of the present study is to examine the effects of DCPs on various organs, the dose dependency and the pathogenetic potential of DCP hepatotoxicity. A single intraperitoneal injection was given to six groups of rats with 0.2 ml of 20% ethanol (control), or 1/8 x, 1/4 x, 1/2 x, 1 x, and 2 x LD50 (0.11 ml/kg) of 1,3-dichloro, 2-propanol (DC2P) diluted in 20% ethanol. After blood samplings, all organs were subjected to histologic examinations with light and electron microscopes. Fresh liver tissues from further 4 control and 4 experimental rats sacrificed 6 hours after the injection of 20% ethanol and 1 x LD50 of DC2P were homogenized and subjected to evaluate lipid peroxidation, glutathione S-transferase activity and reduced glutathione contents in the liver. The rats administered with only ethanol or 1/8 and 1/4 LD50 of DC2P showed no serological or histopathological abnormalities. Marked elevation of serum glutamate pyruvate transaminase (SGPT) with a diffuse massive necrosis of the liver cells were noted in all rats of both the 1 x and 2 x LD50 groups, and irregular zonal necroses were found in 3 of 4 rats injected with 1/2 LD50. There were no serious toxic changes in other organs. Hepatic malondialdehyde level was significantly increased, associated with decreases of liver glutathione S-transferase activity and reduced glutathione content. It was concluded that the serious DC2P-toxicity was mainly found in the livers, dose dependently, and one of the causative mechanisms of this hepatotoxicity might be the lipid peroxidation.

Alanine Transaminase↗
PubMed1998

Setting time and sealing ability of alpha-tricalcium phosphate cement containing titanic oxide.

We developed a new type of calcium phosphate cement for clinical use in endodontics as a root canal sealer or pulp cupping agent. The solid phase of the sealer is composed of 70% of alpha-tricalcium phosphate (alpha-TCP) and 30% of titanic oxide (TiO2), and the liquid phase is 37% citric acid, 5% tannic acid and 58% distilled water. TiO2 was added to control setting time and handling of the cement. We used commercially available calcium phosphate root canal sealer as a control. ISO standards specify that new endodontic products should be examined thoroughly before clinical use. It is important to carry out in vitro cytotoxicity and in vivo histocompatibility tests. We first did in vitro test of setting time and root canal sealing ability of the cement. We found that this developed calcium phosphate cement had an appropriate setting time and excellent sealing ability as a root canal sealer, and concluded that it was suitable for clinical use as a root canal sealer.

Calcium Phosphates↗
PubMed1998

[Long-term follow up of QRS axis deviation].

It has been already described that the average axis of QRS complex is deviated by aging as well as various diseases, such as ventricular overload or bundle branch block. In this study, we first tested the hypothesis that the extra-cardiac factor changes with aging, such as the body shape or diaphragm position, which are represented by body weight (WT) and/or cardiac-thoracic ratio (CTR), are the main cause of QRS axis deviation. In 28 cases including 1 right (RAD) and 27 left axis deviation (LAD) patients whose QRS axis have been deviated during observed periods, WT and X-ray CTR were compared to the degree of axis deviation. Unfortunately no clear relationship was found among these parameters. On the other hand, in 8 cases out of 27 LAD patients, confirmed or suspected left anterior hemiblock (LAH) was found by vector electrocardiogram. Pathological studies showed that the degeneration of the stimulation pathway occurred with aging and it caused the bundle branch block. Therefore, we conclude that the degenerative change in left anterior stimulation pathway by aging should be, at least, one of the cause of the QRS axis deviation.

Aged↗
PubMed1998

[Diagnosis and treatment for recurrent hepatocellular carcinoma].

In order to investigate the mechanism of recurrence of hepatocellular carcinoma (HCC), 322 patients with HCCs (size: < or = 3 cm) treated by percutaneous ethanol injection (PEI), transcatheter arterial embolization (TAE) or radiation therapy were evaluated. Cumulative recurrent rates of new lesions after the initial therapy were 25% (1-year), 57% (2-year) and 71% (3-year). In 116 patients whose tumors were multiple at the time of initial therapy, the recurrent rates were higher compared with 206 patients with a single tumor. In 228 of all patients, new lesions were observed in the noncancerous liver after initial therapy. We observed a single new lesion in 67% of the 134 patients, whose HCC was single at the time of initial therapy. In the remaining 33% of these patients, multiple new lesions were observed. As for the recurrence site, we found new lesions at a different segment of the liver from the initial HCC in 52% of these 134 patients. In the patients with multiple recurrent HCCs, the survival rates were lower in comparison with the patients whose recurrent HCC was single. In the patients whose new lesions were found within 1 year after the initial therapy, the survival rates were also lower compared with the patients whose new lesions were not detected during 1 year. In conclusion, the mechanism of multicentric occurrence may be closely correlated with the intrahepatic recurrence of HCC in consideration of the high incidence of recurrent rates of HCCs and their recurrent pattern.

Antineoplastic Agents↗
PubMed1998

[Repeated arterial infusion of zinostatin stimalamer using port for advanced hepatocellular carcinoma].

Four patients with advanced hepatocellular carcinoma were treated by repeated arterial infusion of zinostatin stimalamer (SMANCS). Every 4 weeks, 4 mg of SMANCS and 4 ml of Lipiodol were administered via the proper hepatic artery using an implantable arterial port. Three patients with advanced liver cirrhosis (Child B or C) could no longer be treated after 2 or 3 courses of SMANCS infusion because of hepatic failure. In the remaining patient also with compensated liver cirrhosis (Child A), a partial response was observed after 5 courses of chemo-infusion, but we discontinued infusion of SMANCS because of hepatic failure. To assess the usefulness of SMANCS for repeated arterial chemo-infusion by the port, we evaluated 103 patients with advanced HCC treated by Lipiodol emulsion mixed with 70 mg of epirubicin (EPI) using a port. An average course was 11 arterial infusions, and the overall response rate was 40%. One-year survival rates were 62% in Child A, 59% in Child B, and 53% in Child C. Compared with Child A and B patients, both elevation of serum total bilirubin levels and decrease of serum albumin levels were observed after 9 months in Child C patients. In conclusion, SMANCS may have more severe hepatic toxicity in comparison with Lipiodol emulsion mixed with EPI.

Aged↗
PubMed1998

[Energy expenditure in patients with pulmonary emphysema].

We evaluated resting energy expenditure (REE) using canopy mode indirect calorimetry in 21 ambulatory, clinically stable outpatients with pulmonary emphysema (age: 69.3 +/- 8.4, %IBW: 79.3 +/- 12.5, FEV1: 0.98 +/- 0.36) and compared it with that of a 14 age-matched healthy controls (age: 71.1 +/- 6.0, %IBW: 94.5 +/- 13.4). We also compared REE in malnourished patients (%IBW < 90; 73.0 +/- 7.6, N = 14) and normonourished patients (%IBW > or = 90; 92.0 +/- 5.6, N = 7). We examined the relation ship between %REE (REE/REEpred. x 100) and measurements of lung function tests in 21 emphysema patients using single regression analysis. The REE of the patient group was significantly higher than that of the control group (%REE; 115.9 +/- 12.0 vs 86.5 +/- 8.7, p < 0.01). The REE of the malnourished patient subgroup was significantly higher than that of the normonourished patient subgroup (%REE; 121.9 +/- 7.9 vs 109.9 +/- 9.2, p < 0.01). There were no significant differences in FEV1(L), RV/TLC(%), TLC(pred.%) or DLco/VA (pred.%) between the two patient subgroups. The REE of the normonourished subgroup was significantly higher than that of control group (%REE; 109.1 +/- 9.2 vs 86.5 +/- 8.7, p < 0.01). There were significant relations hips among %REE and FEV1, %FVC, FEV1% G, %DLco/VA and RV/TLC (p < .05). These findings suggest that elevated REE may have a significant relation ship with abnormal lung function, and that elevated REE may be a cause of malnutrition in clinically stable patients with pulmonary emphysema.

Aged↗
PubMed1998

Natural course of small hepatocellular carcinoma with underlying cirrhosis. A study of 30 patients.

To anticipate the prognosis and choose therapy for patients with relatively early-stage HCCs, we elucidate the natural course of such patients. Thirty cirrhotic patients with small hepatocellular carcinoma (HCC) < 3 cm in size and not receiving anti-cancer treatment were followed by sonography for periods of 6-48 mots. The growth speed varied considerably from case to case, with an average of 6.5+/-5.7 months of doubling time (DT). Growth speed of small HCC is significantly related to histological differentiation of tumors: a slow-growing HCC tends to be well-differentiated and a rapid-growing HCC moderately- or poorly-differentiated. Furthermore, there was a tendency to grow without changing from nodular type in slow-growing HCCs and to multiple nodular or massive types in intermediate- and rapid-growing HCCs. The survival rates of these untreated HCC patients showed a 1-yr survival of 90.7%, a 2-yr survival of 55.0%, and a 3-yr survival of 12.8%. Factors significantly influencing survival of these patients were serum total bilirubin level and DT. This study will provide invaluable data for diagnosing and treating for small HCCs.

Aged↗
PubMed1998

[Thoracoscopic lung volume reduction surgery for emphysema].

In recent years, several institutions have been performing lung volume reduction surgery (LVRS) for emphysema, and have reported that LVRS is effective for patients with emphysema that is resistant to other forms of therapy. However, questions remain about the relationship between the extent of resection and the therapeutic benefits. In our study, 15 men with emphysema underwent thoracoscopic LVRS. We analyzed the effects of LVRS on pulmonary function, exercise performance, and subjective symptoms after both bilateral and unilateral procedures. The patients who underwent the bilateral procedure, demonstrated significantly improved pulmonary function and exercise performance and relief of their subjective symptoms. Those who underwent the unilateral procedure, demonstrated significantly improved pulmonary function and relief of their subjective symptoms. Forced expiratory volume in 1.0 second increased by an average of 51% after the bilateral procedure, and 17% after the unilateral procedure. We conclude that thoracoscopic LVRS is an effective treatment for emphysema, especially with the bilateral procedure.

Aged↗
PubMed1998

[Diagnosis of mycobacterial disease by biochemical and immunological parameters].

A definitive diagnosis of tuberculosis requires the recovery of M. tuberculosis organisms from a patient's secretions, body fluids, or tissues. However, the detection rate of M. tuberculosis is not high in tuberculous pleural effusions. Several studies demonstrated that adenosine deaminase (ADA) level in pleural effusion above 50 IU/L was strongly associated with tuberculosis. ADA has been found to be elevated in serum and several body fluids that are infected by M. tuberculosis. Recently, the simultaneous skin tests of PPDs (M. tuberculosis), PPD-B (M. intracellulare), PPD-Y (M. kansasii) and PPD-F (M. fortuitum), have been reported to be useful in diagnosing mycobacteriosis in the early stage of the disease. Although serodiagnosis of tuberculosis has long been the subject of investigation, no serodiagnostic approach is currently of widespread and clinical utility. At the present time, several serodiagnostic test using enzyme-linked immunosorbent assay (ELISA) for the measurement of IgG antibody to some protein (38-kDa, 30-kDa, 16-kDa and so on) and nonprotein (lipoarabinomannan and cord factor) antigens. Despite an explosion in the techniques of rapid identification of mycobacteria by molecular genetic means, the relative simplicity and low cost of serodiagnosis remain attractive.

Adenosine Deaminase↗
PubMed1997

Improved technique of heterotopic cervical heart transplantation in mice.

BACKGROUND: The method for mouse vascularized heart transplantation have been described using suture and cuff techniques. Technical problems have limited its widespread use. Here, we describe our method of modified cervical heterotopic transplantation with the cuff technique. METHODS: By using a smaller Teflon cuff (external diameter 0.6 mm, internal diameter 0.4 mm) and superfine-tip forceps, it became possible to directly pull the edge of the carotid artery and evert the proximal end of the artery over the cuff. Similarly, the external jugular vein could be easily everted over a 22-gauge cuff with this direct pulling method. RESULTS: By these modifications, the operation time was reduced. It usually takes 20 min for the donor harvest, 15 min for preparation of the cervical vessels, and 15 min for anastomosis. All procedures from the donor harvest through skin closure of the recipient mice can be completed within 1 hr, and ischemic time is within 25-40 min. CONCLUSIONS: This method can be used to investigate cyclophosphamide-induced tolerance and mechanisms of reperfusion injury.

Anastomosis, Surgical↗
PubMed1997

Release of opioid peptides, gluten exorphins by the action of pancreatic elastase.

The release of opioid peptides, gluten exorphins A, which have been isolated from the pepsin-thermolysin digest of wheat gluten, with gastrointestinal proteases was examined. High levels of gluten exorphin A5 (Gly-Tyr-Tyr-Pro-Thr) immunoreactive materials were detected in the pepsin-pancreatic elastase digest by a competitive ELISA. From this digest, gluten exorphin A5, B5 and B4 were isolated. This means that these peptides are released in the gastrointestinal tracts after ingestion of wheat gluten. The yield of gluten exorphin A5 in the pepsin-elastase digest was larger than that in the pepsin-thermolysin digest. The gluten exorphin A5 sequence is found 15 times in the primary structure of the high molecular weight glutenin. The region from which gluten exorphin A5 was released by the action of pancreatic elastase was identified using synthetic fragment peptides.

Cross Reactions↗
PubMed1997

Tissue-specific expression of HSV-tk gene can induce efficient antitumor effect and protective immunity to wild-type hepatocellular carcinoma.

The efficacy of expression of the herpes simplex virus thymidine kinase (HSV-tk) gene under the transcriptional control of the liver-specific albumin gene promoter, followed by ganciclovir treatment, was investigated both in vitro and in vivo. Murine and rat hepatocellular carcinoma (HCC) cells infected with retroviruses carrying the HSV-tk gene under the control of the murine albumin gene promoter were selectively killed by ganciclovir treatment in vitro, whereas non-HCC cells, such as murine mammary tumor cells and fibroblast cells, which were infected with the same retroviruses, were not. Susceptibility of the retroviral-infected HCC cells to ganciclovir was more than 100-fold higher than that of the retroviral-infected non-HCC cells. When mice bearing a bulky HCC mass consisting of the retroviral-infected HCC cells were treated with systemic ganciclovir administration, complete regression of the tumors was observed without any signs of overt toxicity. Profound antitumor effects on preestablished murine HCCs were observed when wild-type HCC cells were implanted into animals with a small percentage of the retroviral-infected counterparts. When only 5% of the cells were infected with retroviruses carrying the HSV-tk gene, significant inhibition of tumor development was observed with systemic ganciclovir treatment. Importantly, animals that were treated with implantation of mixtures of the retroviral-infected and parental HCC cells, followed by ganciclovir administration, did not exhibit tumor formation and resisted subsequent rechallenge with wild-type HCC cells. Our results indicate the feasibility of combination therapy with the HSV-tk gene and ganciclovir for the treatment of HCC.

Animals↗