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H Hara

Publications and source records attributed to H Hara.

At least 19 recordsLinked to original sources
PubMed2006

Distance determination in human ubiquitin by pulsed double electron-electron resonance and double quantum coherence ESR methods.

Recently, distance measurements by pulsed ESR (electron spin resonance) have been obtained using pulsed DEER (double electron-electron resonance) and DQC (double quantum coherence) in SDSL (site directed spin labeling) proteins. These methods can observe long range dipole interactions (15-80A). We applied these methods to human ubiquitin proteins. The distance between the 20th and the 35th cysteine was estimated in doubly spin labeled human ubiquitin. Pulsed DEER requires two microwave sources. However, a phase cycle is not usually required in this method. On the other hand, DQC-ESR at X-band ( approximately 9GHz) can acquire a large echo signal by using pulses of short duration and high power, but this method has an ESEEM (electron spin echo envelope modulation) problem. We used a commercial pulsed ESR spectrometer and compared these two methods.

Algorithms↗
PubMed2006

Cilostazol reduces ischemic brain damage partly by inducing metallothionein-1 and -2.

The neuroprotective effect of cilostazol, an antiplatelet drug, was examined after 24 h permanent middle cerebral artery (MCA) occlusion in mice, and explored the possible underlying mechanism by examining metallothionein (MT)-1 and -2 induction in vivo. Cilostazol (30 mg/kg) was intraperitoneally administered at 12 h before, 1 h before, and just after MCA occlusion. Mice were euthanized at 24 h after the occlusion, and the neuronal damage was evaluated using 2,3,5-triphenyltetrazolium chloride (TTC) staining. Cilostazol significantly reduced the infarct area and volume, especially in the cortex. Real-time RT-PCR revealed increased mRNA expressions for MT-1 and -2 in the cortex of normal brains at 6 h after cilostazol treatment without MCA occlusion. MT-1 and -2 immunoreactivity was also increased in the cortex of such mice, and this immunoreactivity was observed in the ischemic hemisphere at 24 h after MCA occlusion (without cilostazol treatment). The strongest MT-1 and -2 immunoreactivity was detected in MCA-occlused mice treated with cilostazol [in the peri-infarct zone of the cortex (penumbral zone)]. These findings indicate that cilostazol has neuroprotective effects in vivo against permanent focal cerebral ischemia, especially in the penumbral zone in the cortex, and that MT-1 and -2 may be partly responsible for these neuroprotective effects.

Animals↗
PubMed2006

Rifampicin attenuates the MPTP-induced neurotoxicity in mouse brain.

Rifampicin, an antibacterial drug, is highly effective in the treatment of tuberculosis and leprosy. Recently, it has been reported to have neuroprotective effects in in vitro and in vivo models. This study was designed to elucidate its neuroprotective effects against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neurotoxicity (known as an in vivo mouse model of Parkinson's disease). Mice were injected intraperitoneally (i.p.) with MPTP (10 mg/kg) four times at 1-h intervals, and brains were analyzed 3 or 7 days later. Rifampicin at 20 mg/kg (i.p., twice) had protective effects against MPTP-induced neuronal damage (immunohistochemical changes in tyrosine hydroxylase) in both the substantia nigra and striatum. Rifampicin also protected against the MPTP-induced depletions of dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) in the striatum. The maximal concentrations of rifampicin between 30 and 240 min after a single rifampicin injection (20 mg/kg, i.p.) were 2.6 microM (at 30 min) in plasma and 0.77 microM (at 60 min) in striatum. Next, the effects of rifampicin on oxidative stress [lipid peroxidation in mouse brain homogenates and free radical-scavenging activity against diphenyl-p-picrylhydrazyl (DPPH)] were evaluated to clarify the underlying mechanism. At 1 microM or more, rifampicin significantly inhibited both lipid peroxidation in the striatum and free radical production. These findings suggest that in mice, rifampicin can reach brain tissues at concentrations sufficient to attenuate MPTP-induced neurodegeneration in the nigrostriatal dopaminergic neuronal pathway, and that an inhibitory effect against oxidative stress may be partly responsible for its observed neuroprotective effects.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed2006

Detection of human papillomavirus type 34 in Bowen's disease on the pubic area.

We describe an 86-year-old man with Bowen's disease on the pubic area. The lesion was clinically a black-brownish keratotic nodule resembling seborrheic keratosis. Histopathological findings showed those of Bowen's disease and harboured human papillomavirus type 34 DNA. Genital, but not skin, human papillomaviruses are responsible for Bowen's disease on the skin.

Aged↗
PubMed2006

Altered alpha1-syntrophin expression in myofibers with Duchenne and Fukuyama muscular dystrophies.

Alpha1-syntrophin, a scaffolding adapter and modular protein, is a cytoplasmic component of the dystrophin glycoprotein complex. This study investigated immunohistochemically the expression of alpha1-syntrophin in Duchenne and Fukuyama muscular dystrophies (DMD and FCMD, respectively). Biopsied muscles of five DMD, five FCMD, five normal controls and five disease controls (three myotonic and two facioscapulohumeral dystrophies) were analyzed. Immunoblot analysis showed that anti-alpha1-syntrophin antibody had a decreased reaction in both DMD and FCMD muscle extracts. Biopsied muscle sections and their serial sections were immunostained with rabbit anti-alpha1-syntrophin and rabbit anti-muscle-specific beta-spectrin antibodies, respectively. Immunoreactive patterns of sarcolemma were classified into (i) a continuously positive immunostaining pattern, (ii) a partially positive immunostaining pattern, (iii) a negative immunostaining pattern and (iv) a faint but entire surface positive immunostaining pattern. The group mean percentages of alpha1-syntrophin and beta-spectrin immunonegative myofibers in the DMD group were 39.3% and 10.8%, respectively, while those in the FCMD group were 45.5% and 10.4%, respectively. These values were statistically significant compared with those of disease control and normal control muscles. Thus we found that dystrophin-deficient DMD muscles contained significant numbers of alpha1-syntrophin-positive fibers and significant numbers of alpha1-syntrophin-negative fibers were present in dystrophin-positive muscles of severe muscular dystrophy such as FCMD. Alpha-dystrobrevin immunoreactivity was tested in DMD muscles and appreciable amounts of alpha-dystrobrevin that binds to syntrophin were found in DMD muscle membranes.

Adolescent↗
PubMed2005

The functional sites of chlorophylls in D1 and D2 subunits of photosystem II identified by pulsed EPR.

The functional site of ChlZ, an auxiliary electron donor to P680+, was determined by pulsed ELDOR applied to a radical pair of YD * and Chlz+ in oriented PS II membranes from spinach. The radical-radical distance was determined to be 29.5 A and its direction was 50 degrees from the membrane normal, indicating that a chlorophyll on the D2 protein is responsible for the EPR Chlz+ signal. Spin polarized ESEEM (Electronin Spin Echo Envelop Modulation) of a 3Chl and QA - radical pair induced by a laser flash was observed in reaction center D1D2Cytb559 complex, in which QA was functionally reconstituted with DBMIB and reduced chemically. QA -ESEEM showed a characteristic oscillating time profile due to dipolar coupling with 3Chl. By fitting with the dipolar interaction parameters, the distance between 3Chl and QA - was determined to be 25.9 A, indicating that the accessory chlorophyll on the D1 protein is responsible for the 3Chl signal.

Animals↗
PubMed2005

Evaluation of developmental toxicity of 1-butanol given to rats in drinking water throughout pregnancy.

The objective of this study was to evaluate the developmental toxicity of 1-butanol in rats. Pregnant rats were given drinking water containing 1-butanol at 0.2%, 1.0% or 5.0% (316, 1454 or 5654 mg/kg/day) on days 0-20 of pregnancy. A significant decrease in maternal body weight gain accompanied by reduced food and water consumption was found at 5.0%. No significant increase in the incidence of pre- and postimplantation embryonic loss was observed in any groups treated with 1-butanol. Fetal weight was significantly lowered at 5.0%. Although a significant increase in the incidence of fetuses with skeletal variations and decreased degree of ossification was found at 5.0%, no increase in the incidence of fetuses with external, skeletal and internal abnormalities was detected in any groups treated with 1-butanol. The data demonstrate that 1-butanol is developmental toxic only at maternal toxic doses. No evidence for teratogenicity of 1-butanol was noted in rats. Based on the significant decreases in maternal body weight gain and fetal weight, it is concluded that the no observed adverse effect levels (NOAELs) of 1-butanol for both dams and fetuses are 1.0% (1454 mg/kg/day) in rats.

1-Butanol↗
PubMed2005

Preformed antibodies to alpha1,3-galactosyltransferase gene-knockout (GT-KO) pig cells in humans, baboons, and monkeys: implications for xenotransplantation.

OBJECTIVE: The aim of our study was to determine the prevalence and cytotoxicity of primate antibodies directed to antigens other than Galalpha1,3Gal (Gal), termed nonGal antigens. METHODS: Sera from human, baboon, and cynomolgus monkeys were tested by flow cytometry for IgM and IgG binding to both wild-type (WT) and GT-KO pig peripheral mononuclear cells (PBMC). Also, complement-dependent cytotoxicity assays were performed. RESULTS: All species demonstrated significantly higher antibody binding and cytotoxicity to WT cells compared to GT-KO cells (P < .01). Cynomolgus monkeys had significantly higher IgM binding to WT and GT-KO cells than did baboons or humans (P < .01). Furthermore, approximately 50% of both human and baboon sera proved to be lytic to GT-KO cells, compared to 76% of monkey sera (P < .01). CONCLUSIONS: We confirm the advantage of using GT-KO pig grafts over WT pig grafts. However, our results suggest that, compared to the cynomolgus monkey, the baboon may be a more suitable model to study antibody-mediated rejection of GT-KO pig grafts.

Animals↗
PubMed2005

Multiple fixed drug eruption due to drug combination.

We report the case of a multiple fixed drug eruption (FDE) after taking 1 g of PL and 100 mg of levofloxacin (Cravit) at the same time. Patch tests with PL alone, levofloxacin alone and the combination of PL and levofloxacin were all negative on the involved and uninvolved sites. Lymphocytic stimulation tests were also negative for PL alone, levofloxacin alone and the combination of PL and levofloxacin. Oral provocation tests with PL alone or levofloxacin alone produced no reactivation. However, we could provoke multiple erythematous plaques on the involved areas by taking a 1/10th dose of the combination of PL and levofloxacin at the same time. Drug eruption due to a drug combination appears to be very rare. This is the first case of multiple FDE caused by taking PL-levofloxacin combination.

Acetaminophen↗
PubMed2005

Optic disc topographic parameters measured in the normal cynomolgus monkey by confocal scanning laser tomography.

AIM: To study optic disc topographic parameters in normal cynomolgus monkeys by Heidelberg retina tomograph (HRT). METHODS: 12 optic disc topographic parameters were investigated in 36 normal eyes in 18 male monkeys. Mean (SD) and interocular differences were obtained for each parameter from three independent measurements made during a 1 week period. Correlations among the topographic parameters were analysed, too. RESULTS: No significant differences between right and left eyes were detected for any topographic parameters. Disc area, rim area, and height variation contour showed smaller right-left differences than other parameters. The coefficients of variation for rim area, height variation contour, rim volume, mean cup depth, maximum cup depth, mean retinal nerve fibre layer (RNFL) thickness, and RNFL cross section area were less than 10% (for rim area, less than 5%). Rim area and height variation contour showed relatively weak interrelations and neither showed a correlation with disc area. CONCLUSION: For evaluating time related changes in the optic disc by HRT in monkeys, rim area and height variation contour might be useful parameters because coefficients of variation and right-left differences were lower than for other parameters and because these parameters showed weak interrelations and no correlation with disc area.

Animals↗
PubMed2004

Induction of drug-metabolizing enzymes and transporters in human bronchial epithelial cells by beclomethasone dipropionate.

Inhaled steroids are the most potent anti-inflammatory therapy commonly used in bronchial asthma. There are, however, a small number of asthmatic patients who do not respond to inhaled steroid-treatment. The stimulation of metabolism and excretion of inhaled drugs at bronchial tissues might lead to a decrease in the effect of the drugs, although the molecular mechanism of this resistance is unclear. In this study, we found that beclomethasone dipropionate (BDP) stimulated the expression of mRNAs for uridine 5'-diphosphate glucuronosyl transferase 2B4 and 2B11, and transporters such as multidrug resistance P-glycoprotein, multidrug resistance-associated protein 1 and 2 in cultured bronchial epithelial cells. It is possible that the individual differences of expression of drug metabolizing enzymes and transporters and their enhancement with BDP are implicated in the individual differences of reactivity over steroid medical treatment.

ATP Binding Cassette Transporter, Subfamily B↗
PubMed2004

Relationship of plasma extracellular-superoxide dismutase level with insulin resistance in type 2 diabetic patients.

Extracellular-superoxide dismutase (EC-SOD) is a secretory glycoprotein located in blood vessel walls at high levels and may be important in the antioxidant capability of vascular walls. The aim of this study was to assess plasma levels of EC-SOD and to evaluate the relationship of the EC-SOD level with insulin resistance in type 2 diabetic patients. We determined plasma EC-SOD in 122 patients and found for the first time that the EC-SOD level was strongly and positively related to adiponectin (r=0.503, P < 0.001), and significantly and inversely related to fasting plasma glucose (FPG) (r=-0.209, P=0.022), body-mass index (BMI) (r=-0.187, P=0.040) and homeostasis model assessment-insulin resistance index (HOMA-R) (r=-0.190, P=0.039). Stepwise-multiple regression analysis also showed a significant influence of adiponectin (F=33.27) on the EC-SOD level. Administration of pioglitazone to 19 diabetic patients significantly increased the plasma levels of EC-SOD (69.9+/-19.3 ng/ml to 97.4+/-25.9 ng/ml; P < 0.0001) and adiponectin, while it decreased tumor necrosis factor-alpha (TNF-alpha). The present observations suggest that factors related to the pathogenesis of insulin resistance play an important role in the regulation of the plasma EC-SOD concentration. It is possible that the increase in the EC-SOD level by pioglitazone administration in diabetic patients is due to a decline of TNF-alpha, which is known to suppress EC-SOD expression.

Adiponectin↗
PubMed2003

Altered aquaporin 4 expression in muscles of Fukuyama-type congenital muscular dystrophy.

This study was undertaken to investigate the expression of aquaporin 4 (AQP4) in the muscle plasma membrane of children with Fukuyama-type congenital muscular dystrophy (FCMD) at protein and mRNA levels. The biopsied six muscles with FCMD, six histochemically normal muscles and eight disease control muscles were analyzed by means of immunoblots, immunohistochemistry and reverse-transcription polymerase chain reaction (RT-PCR). Immunoblots showed that the band of FCMD muscle extracts stained with anti-AQP4 antibody was faint in comparison with that of normal muscle extracts. The immunohistochemistry revealed that most of the FCMD myofibers showed negative immunostaining with anti-AQP4 antibody, although the partially positive immunostaining of sporadic FCMD myofibers was noted. The immunoreactivity was positive with anti-dystrophin and anti-beta-spectrin antibodies in almost all FCMD myofibers. The quantitative RT-PCR demonstrated that the AQP4 mRNA level of the FCMD muscles was markedly reduced. On the basis of these findings, we conclude that the expression of AQP4 in FCMD myofibers is reduced and the reduced content of AQP4 mRNA in FCMD muscles may be related to the decreased expression of AQP4 at the muscle plasma membrane of FCMD myofibers.

Aquaporin 4↗