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Biomedical subjects

K Hirano

Publications and source records attributed to K Hirano.

At least 91 records · Page 5Linked to original sources
PubMed2001

Inhibition of aminopeptidase N (AP-N) and urokinase-type plasminogen activator (uPA) by zinc suppresses the invasion activity in human urological cancer cells.

Zinc is an essential heavy metal and is more abundant in human prostate and kidney than in other tissues. The effects of zinc on the invasion activity of human prostate and renal cancer cell lines, PC-3, LNCaP and SKRC-1, were investigated in vitro using a Transwell cell-culture chamber and were compared with specific protease inhibitors for MMPs, uPA and AP-N, respectively. The invasion activity of PC-3 cells was effectively suppressed by zinc and by all protease inhibitors in a dose-dependent manner. The invasion activity of LNCaP cells was almost unaffected by these inhibitors. In SKRC-1 cells, the invasion activity was strongly suppressed by MP03, although a moderate inhibition by zinc and bestatin was observed. The purified AP-N activity was strongly inhibited by zinc at a concentration similar to that suppressing the invasion activity of PC-3 cells and this inhibition by zinc was apparently competitive. Although the purified uPA activity was also inhibited by zinc, this inhibition was uncompetitive. AP-N was expressed abundantly on the membrane fraction of PC-3 cells among these cells tested, while its expression on the membrane fraction of SKRC-1 cells was weaker than that of PC-3 cells. The expression of uPA was also highest on the membrane fraction of PC-3 cells. These results suggest that AP-N and uPA may be involved in the invasion of human prostate cancer cells and that zinc probably participates in the invasion and metastasis of cancer cells through the regulation of the enzymatic activity of AP-N and uPA in human cancerous prostate.

Adenocarcinoma↗
PubMed2001

Orthovanadate decreases leptin secretion from isolated mouse fat pads.

When isolated mouse fat pads were incubated with orthovanadate (vanadate) or insulin for up to 4 h, the leptin secretion into the medium was decreased by vanadate and increased by insulin. Propranolol, a nonspecific antagonist of beta-adrenergic receptors, bupranorol, a specific antagonist of beta3-adrenergic receptor, and H-89, an inhibitor of cAMP-dependent protein kinase (PKA) all inhibited the decrease by vanadate to various extents. In contrast, no inhibition was observed with specific antagonists of beta1- and beta2-adrenergic receptors or with inhibitors of protein kinase C and Ca/calmodulin kinase. Short-term incubation of the fat pads with vanadate showed a transient increase in the cellular cAMP content; this increase was inhibited by propranolol and bupranolol. Vanadate had no effect on the incorporation of [3H]-leucine into proteins of the fat pads with a 4-h incubation, although insulin stimulated the incorporation. The decreasing effect of vanadate on the leptin secretion seems to be independent of the regulation of protein synthesis. These results suggest that vanadate decreases the leptin secretion through mechanisms involving the increase in cellular cAMP content via beta3-adrenergic receptor, probably leading to the activation of PKA.

Adipose Tissue↗
PubMed2001

Pharmacokinetics of granisetron in adults and children with malignant diseases.

Granisetron (GRN) is widely used for patients with various cancers who suffer from chemotherapy-induced vomiting and nausea. The, pharmacokinetics of GRN has not been fully evaluated in such patients, however, and its dosage regimen is still controversial. In this study, we determined GRN levels in serum and urine from lung cancer patients and children suffering from cancer after intravenous infusion. In lung cancer patients, the interindividual variations in t(1/2beta), area under the concentration-time curve (AUC), and Vd(beta) were relatively smaller than expected from previous reports on healthy subjects, while t(1/2beta) was prolonged more than 5-fold in healthy subjects. Urinary excretion of unchanged GRN in lung cancer patients was ca. 15% of dose, consistent with previous reports, and one individual demonstrated an even higher urinary excretion (ca. 45%). The pharmacokinetic parameters of GRN in child cancer patients varied markedly among individuals, and some child patients had smaller t(1/2beta) than adult patients. In these cases, GRN should be administered at shorter intervals. These results suggested that a pharmacokinetic study of GRN was necessary for planning a dosage regimen and managing chemotherapy-induced vomiting and nausea.

Adolescent↗
PubMed2001

Medicinal foodstuffs. XXIII. Structures of new oleanane-type triterpene oligoglycosides, basellasaponins A, B, C, and D, from the fresh aerial parts of Basella rubra L.

Basellasaponins A, B, C, and D, oleanane-type triterpene oligoglycosides having the dioxolane-type substituent, were isolated from the fresh aerial parts of Basella rubra L. together with betavulgaroside I, spinacoside C, and momordins IIb and IIc. The chemical structures of basellasaponins A, B, C, and D were determined from chemical and physicochemical evidence.

Carbohydrate Conformation↗
PubMed2001

[Analysis of inquiries about prescriptions at the pharmacy of Gifu Pharmaceutical University].

The Ministry of Health, Labour and Welfare explains the objectives of promotion of separation of the pharmacy and clinics as the elimination of duplicated prescription of similar drugs and drug interactions caused by treatment at several departments or hospitals, and sufficient guidance in the use of drugs by pharmacists. The Pharmacy of Gifu Pharmaceutical University has dispensed prescriptions by outside medical organizations as its routine activity. In this study, the contents of question inquiries handled in routine activities were compiled and analyzed, and their meaning was evaluated. The contents of question inquiries were accumulated using data cards. The data obtained during 2 and a half years (562 cases) were analyzed. The percentage of the number of inquiries relative to the number of prescriptions was highest at 1.86% during the first 3 months and was 1.05-1.71% per 3 months thereafter. The inquiries were most frequently about "the dosage/regimen" (153 cases), followed by "discrepancy between the contents of prescription and understanding of the patient" (88 cases) and "problems about insurance coverage" (80 cases). There were also 16 inquiries about "the possibility of contraindications and adverse reactions" and 15 inquiries about "duplicated prescription", which may have exerted serious effects on the patients. Eighty nine % of the inquiries have led to changes in the prescriptions, and about half of these cases were discovered by consultation with the patients or a review of the drug history. Proper and positive execution of these operations in routine pharmacy work is considered to lead to appropriate inquiries about problems with prescriptions and, thus, contribute to the proper use of drugs and prevention of malpractice.

Drug Administration Schedule↗
PubMed2001

Maintenance of the differentiated type II cell characteristics by culture on an acellular human amnion membrane.

We have developed a Culture system for guinea pig alveolar type II cells using an epithelium-denuded human amnion membrane as a substratum. The differentiated morphology was maintained for 3 wk by both air-interface feeding and immersion feeding when type II cells were cultured on the basement membrane side of the amnion with fibroblasts on the opposite side (coculture). Functionally high levels of surfactant protein B (SP-B) and C (SP-C) messenger ribonucleic acids (mRNAs) were expressed even after the 3-wk cultivation and surfactant protein A mRNA was detected on day 10 of the culture. The differentiation was also maintained when fibroblasts were cultured on lower chambers of the culture plates (separate culture). In contrast, culture of type II cells without fibroblasts (monoculture) could not preserve the mature morphology. When the monoculture was supplemented with keratinocyte growth factor or hepatocyte growth factor, a monolayer of rather cuboidal type II cells with apical microvilli was maintained. However, the percent area of lamellar bodies in these cells was significantly less than that in freshly isolated type II cells, and mRNA expressions of SP-B and SP-C were also considerably suppressed. These findings suggest that other growth factors or combinations of these factors are necessary for the maintenance of the differentiated phenotype. As substratum, a permeable collagen membrane or a thin gel layer of Engelbreth-Holm-Swarm mouse sarcoma extracts did not preserve the mature characteristics. This culture system using an acellular human amnion membrane may provide novel models for research in type II cells.

Amnion↗
PubMed2001

Role of heme oxygenase-1 and Kupffer cells in the production of bilirubin in the rat liver.

Heme oxygenase (HO)-1, the heme-degrading enzyme in macrophages, plays a key role in bilirubin metabolism. HO-1 is expressed in various tissue macrophages, especially Kupffer cells. This study aimed to examine the roles of macrophages and HO-1 in the modulation of heme catabolism in rat livers. Rats treated with or without liposome-encapsulated dichloromethylene diphosphonate, a macrophage-depleting reagent, were administered with heat-denatured red blood cells (h-RBC), and the time course of the biliary output of bilirubin and the expressions of HO-1 mRNA and protein were monitored. Immunohistochemistry in the control rat liver revealed that Kupffer cells constitute a major cellular component expressing HO-1, while hepatocytes exhibited little expression. The levels of HO-1 expression in Kupffer cells were elevated immediately after injection of h-RBC. In Kupffer cell-depleted livers, however, HO-1-expressing cells were not detected even after h-RBC administration. HO-1 mRNA levels were elevated at 2 h after administration of h-RBC in control rat livers, while they were very low in Kupffer cell-depleted rat livers. The control and Kupffer cell-depleted groups exhibited distinct time courses of biliary bilirubin excretion. In the untreated control rats, total bilirubin excretion increased about two-fold at 5 h after h-RBC administration. In contrast, the Kupffer cell-depleting treatment decreased the level of bilirubin production; administration of h-RBC to Kupffer cell-depleted rats did not accelerate the generation of bilirubin. These results suggest that Kupffer cells serve both as a sensor for scenesent RBC clearance and an effector that upregulates heme-degrading capacity and bilirubin production.

Animals↗
PubMed2001

Twenty-six-week carcinogenicity study of sulfamethoxazole in CB6F1-Tg-rasH2 mice.

Sulfamethoxazole (SMX), a hormone-mediated rodent-specific nongenotoxic carcinogen, was administered to CB6F1 mice carrying a human prototype c-Ha-ras gene (Tg-rasH2) at doses of 0, 25, 100 or 400 mg/kg/day and to the wild-type mice at a dose of 400 mg/kg/day in feed for 26 weeks to evaluate the carcinogenicity and to validate the Tg-rasH2 model. N-Methyl-N-nitrosourea was administered at an intraperitoneal dose of 75 mg/kg to Tg-rasH2 as a positive control and the experimental system was confirmed to be valid. Histopathological examination revealed adenomas of the lung and Harderian gland and hemangiosarcoma of the spleen at low frequencies in the Tg-rasH2 treated with SMX; however, no statistically significant differences were observed either in the onset or prevalence rates of these neoplasms compared with that in the control group. Between the wild-type mice and Tg-rasH2, the onset rate and prevalence of the neoplasms were not significantly different, but the neoplasms tended to be more frequent in Tg-rasH2 mice showing a sensitivity to tumorigenicity. Follicular epithelial cell hyperplasia was observed in the thyroid gland in the groups of Tg-rasH2 given 100 mg/kg SMX or more, but no neoplastic lesion was observed. SMX was judged to be negative for carcinogenic potential in Tg-rasH2 in the present study.

Animals↗
PubMed2001

Conjugation with L-Glutamate for in vivo brain drug delivery.

In vitro studies have shown that conjugation of a model compound [p-di(hydroxyethyl)-amino-D-phenylalanine (D-MOD)] with L-Glu can improve D-MOD permeation through the bovine brain microvessel endothelial cell monolayers (Sakaeda et al., 2000). The transport of this D-MOD-L-Glu conjugate is facilitated by the L-Glu transport system. In this paper, we evaluate the in vivo brain delivery of model compounds (i.e. D-MOD, p-nitro-D-phenylalanine (p-nitro-D-Phe), 5,7-dichlorokynurenic acid (DCKA) and D-kyotorphin) and their L-Glu conjugates. DCKA was also conjugated with L-Asp and L-Gln amino acids. The analgesic activities of D-kyotorphin and its L-Glu conjugate were also evaluated. The results showed that the brain-to-plasma concentration ratio of D-MOD-L-Glu was higher than the D-MOD alone; however, the plasma concentration of both compounds were the same. The plasma concentration of p-nitro-D-Phe-L-Glu conjugate was higher than the parent p-nitro-D-Phe; however, the brain-to-plasma concentration ratio of p-nitro-D-Phe was higher than its conjugate. On the other hand, both DCKA and DCKA conjugates have a low brain-to-plasma concentration ratio due to their inability to cross the blood-brain barrier (BBB). The L-Asp and L-Glu conjugates of DCKA have elevated plasma concentrations relative to DCKA; however, the DCKA-L-Gln conjugate has the same plasma concentration as DCKA. For D-kyotorphin, both the parent and the L-Glu conjugate showed similar analgesic activity. In conclusion, conjugation of a non-permeable drug with L-Glu may improve the drug's brain delivery; however, this improvement may depend on the physicochemical and receptor binding properties of the conjugate.

Animals↗
PubMed2001

Resistance of Mycobacterium tuberculosis to four first-line anti-tuberculosis drugs in Japan, 1997.

SETTING: Five years after the last survey of drug-resistant tuberculosis in Japan, a nationwide survey was conducted by the Tuberculosis Research Committee. OBJECTIVE: To determine the prevalence of and risk factors for resistance to four first-line anti-tuberculosis drugs. DESIGN: Cultures were obtained from patients hospitalized at 78 hospitals in different districts of Japan throughout a 6-month period, 1 June-30 November 1997. Drug susceptibility testing was carried out at the Research Institute of Tuberculosis, Tokyo, one of the supranational reference laboratories of the WHO/IUATLD global project. RESULTS AND CONCLUSION: Among patients with no prior treatment, resistance to any of the four drugs was found in 10.3%, and the prevalence of primary multidrug resistance (MDR) was 0.8%. The prevalence of acquired resistance was 42.4% for any of the four drugs and 19.7% for MDR, indicating a high prevalence rate compared with those reported in the WHO/IUATLD global project. About 73% of resistant isolates from new cases were resistant to one drug, while 64.3% of resistant isolates from the re-treatment cases were resistant to two or more drugs (P < 0.0001). No significant differences in resistance rates by sex, age group, nationality, district, and/or accompanying diseases were observed in any of the new or re-treatment cases. Other factors associated with the high prevalence in re-treatment cases remain to be determined.

Antitubercular Agents↗
PubMed2001

[A case of infected subdural hematoma due to Campyrobacter fetus].

A 20-year-old male presented fever, nausea and headache 1 week after eating uncooked liver. On admission, it was revealed he had suffered a closed head injury 3 months before without unconsciousness. On admission, computed tomography scan showed a left chronic subdural hematoma. Gd-DTPA magnetic resonance images revealed unusual enhancement of the capsule and linear enhancement of the subarachnoid space. The patient underwent burr hole irrigation and drainage. The culture of the hematoma content showed Campylobacter fetus. Therefore, the diagnose was infected subdural hematoma. A drainage operation and administration of antibiotics were effective. Our case suggests that enhanced magnetic resonance images are useful for diagnosis and follow-up of infected subdural hematoma.

Adult↗
PubMed2001

[CD36].

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CD36 Antigens↗
PubMed2001

Efficacy of cutting balloon angioplasty for in-stent restenosis: an intravascular ultrasound evaluation.

BACKGROUND: The increase in the use of stents has seen the increasing emergence of in-stent restenosis (ISR). Reports suggest that the Cutting Balloon (Interventional Technologies, San Diego, California) may be a useful treatment modality for this new clinical entity. METHODS: In this study, we compared the efficacy of Cutting Balloon angioplasty (CBA) with conventional balloon angioplasty (PTCA) for ISR in 47 patients (47 lesions). Results were evaluated with intravascular ultrasound (IVUS). The CBA group included 25 patients (mean age, 65 +/- 78 years; 7 females) and the PTCA group included 22 patients (mean age, 69 +/- 51 years; 6 females). RESULTS: The procedural success rate was 100% in both groups. IVUS showed that luminal area acute gain was larger in the CBA group (2.5 +/- 0.8 mm2) compared to the PTCA group (1.8 +/- 1.0 mm2), while late loss was smaller in the CBA group (0.5 +/- 0.4 mm2) compared to the PTCA group (1.3 +/- 0.5 mm2). The change in total area was similar in both groups. The increase in area at the stented portion was 0.4 +/- 0.8 mm2 in the CBA group and 1.2 +/- 0.5 mm2 in the PTCA group. The restenosis rate at follow-up (mean follow-up, 5.4 months) was higher in PTCA patients (59%) than in the CBA patients (24%). CONCLUSION: CBA may result in no increase in total vessel area, a constant stent area, a decrease in plaque area, and an increase in lumen area (induced by the decrease in plaque area). Our IVUS findings suggest that compared to PTCA, the dilatation mechanism of CBA may be associated with reduced dilatation of both the total vessel area and the stent area for ISR. The mechanism of this modality may minimize injury to the intimal membrane and may potentially be a primary device for in-stent restenosis in the future.

Aged↗
PubMed2001

[A study on resistance of Mycobacterium tuberculosis to four first-line anti-tuberculosis drugs in Japan: comparison of results in the local facilities and in the reference laboratory, in 1997].

Five years after the last survey of drug-resistant tuberculosis in Japan, a nationwide survey was conducted by the Tuberculosis Research Committee (Ryoken). A total of 78 hospitals in various districts of Japan participated in this cooperative study. Each collaborating laboratory sent all the isolated mycobacterial cultures during June 1 to November 30, 1997 to the Research Institute of Tuberculosis (RIT), which is one of the Supranational Reference Laboratories of the WHO/IUATLD Global Project on Anti-tuberculosis Drug Resistance Surveillance. At RIT identification and drug susceptibility of Mycobacterium tuberculosis isolates were reexamined. The RIT received a total of 2,167 cultures. Among them, 523 cultures were excluded from further examinations because of various reasons, such as growth of mycobacteria other than tubercle bacilli (MOTT, 453), mixed cultures of M. tuberculosis and MOTT (16), and contamination or non-viability (54). Thus drug susceptibility test results were available for 1,644 cultures, including 47 from foreign-born people. In the local laboratories, the absolute concentration method using 1% Ogawa egg slant (standard method, 26 hospitals), its modified methods using a 48-well plate (Microtiter method, 29 hospitals) and a 16-well plate (Well-pack method, 7 hospitals), combination of above 2 or 3 methods (13 hospitals), and other method (3 hospitals) were used for drug susceptibility testing, and the proportion method using 1% Ogawa egg slant was used in the RIT. The results in the local laboratories were compared with those in the RIT. A high concordance rate (over 90%) was seen in the testing for 1 microgram/ml of isoniazid (INH), rifampin (RFP) and streptomycin (SM), but the rate was lower (under 90%) in the testing for 0.1 microgram/ml of INH and ethambutol (EMB). However, there was no significant difference in the concordance rates according to the test drugs among methods for drug susceptibility testing used in the local laboratories. Median concordance rates between the results with the standard method, Microtiter method and Well-pack method in the local laboratories, and those in the RIT were 95.9%, 93.2% and 96.4% respectively. Relatively lower concordance rates were seen in the laboratories using the Microtiter method related to high overestimation rates (median overestimation rate of 5.3%), compared with 1.2% and 2.3% in the laboratories using the standard method and Well-pack method, respectively. However, relatively lower concordance rates (less than 90%) were seen in the laboratories using any of the three methods, indicating that there are variations among facilities. Part of the results concerning the resistance patterns to four first-line anti-tuberculosis drugs were reported elsewhere.

Ethambutol↗