Drug–drug interactions in the metabolism of imidafenacin: Role of the human cytochrome P450 enzymes and UDP-glucuronic acid transferases, and potential of imidafenacin to inhibit human cytochrome P450 enzymes

Imidafenacin (IM), 4-(2-methyl-1H-imidazol-1-yl)-2,2-diphenylbutanamide, is a newly synthesized antimuscarinic drug developed for the treatment of overactive bladder. To predict clinically relevant drug interactions in the metabolism of IM, the paper investigated: (1) the major enzymes responsible for the metabolism of IM, (2) the effects of concomitant drugs on the inhibition of metabolism of IM, and (3) the effects of IM and its metabolites on the inhibition of human cytochrome P450 (CYP). The elimination of IM and production of oxidative metabolites were mainly catalysed by recombinant CYP3A4, and the elimination of IM by human liver microsomes (HLM) was markedly inhibited by co-incubation with ketoconazole. The production of the N-glucuronide metabolite was only catalysed by recombinant UGT1A4. Clinically established CYP3A4 inhibitors including itraconazole, ketoconazole, erythromycin and clarithromycin inhibited the elimination of IM in HLM. IM and its major metabolites did not affect the activities of CYP enzymes in vitro. The results suggest that the major enzymes responsible for the metabolism of IM are CYP3A4 and UGT1A4, and oxidative metabolism of IM is reduced by concomitant administration of CYP3A4 inhibitors. In contrast, IM and its metabolites have no inhibitory effect on the CYP-mediated metabolism of concomitant drugs.

Concentration and age-dependent elimination kinetics of polychlorinated dibenzofurans in Yucheng and Yusho patients

Half-life estimates of three polychlorodibenzofurans (PCDFs) were calculated using serial blood samples collected over a 15 to 19-year period. Blood fat PCDFs were modeled in eight individuals who were exposed to contaminated rice oil in Japan (Yusho, n = 5) and in Taiwan (Yucheng, n = 3). The elimination kinetics of PCDFs were concentration-dependent, with faster rates observed at higher concentrations and the apparent transition to slower rates occurring at about 1-3 ppb. Average half-lives of 1.1, 2.3, and 1.5 years above the transition concentration and 7.2, 5.7, and 3.5 years below it were estimated for 2,3,4,7,8-pentaCDF, 1,2,3,4,7,8-hexaCDF, and 1,2,3,4,6,7,8-heptaCDF, respectively. A positive linear correlation of half-life with age was observed for the combined group, with a rate of increase of 0.19, 0.12, and 0.05-year half-life per year of increase in age for penta-, hexa-, and hepta-CDF, respectively. The distinctly younger Yucheng patients exhibited far lower variability in half-lives and age-related trends that were quite consistent with the corresponding data on 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) for younger persons exposed in the Seveso incident. These age- and concentration-dependent half-lives for PCDFs may have important risk assessment implications for estimating body burdens. The current study provides limited additional evidence that PCDFs, like TCDD, are more rapidly eliminated in younger individuals.

Characterization of adipose tissue-derived cells isolated with the Celution system

BACKGROUND

The therapeutic potential of using stem cells is tremendous. Mesenchymal stromal cells (MSC) have now been isolated in various tissues including bone marrow (BM), muscle, skin and adipose tissue. Among them, adipose tissue could be one of the most suitable cell sources for cell therapy, because of its easy accessibility, minimal morbidity and abundance of stem cells. The large numbers of stem cells in adipose tissue means that clinically relevant stem cell numbers could be extracted from the tissue, potentially eliminating the need for in vitro expansion. To utilize these characteristics of adipose tissue fully, Cytori Therapeutics Inc. has developed a closed system called Celution to isolate and concentrate stem cells and regenerative cells automatically from adipose tissue.

METHODS

Adipose tissue-derived cells were isolated using the Celution system. The output from the Celution was characterized using multicolor FACS analysis with CD31, CD34, CD45, CD90, CD105 and CD146. The multidifferentiation potential of the cells was analyzed using adipogenic and osteogenic media.

RESULTS

Our results showed that cells from the Celution are composed of heterogeneous cell populations including adipose-derived stem cells (ASC) (CD31- CD34+ CD45- CD90+ CD105- CD146-), endothelial (progenitor) cells (CD31+ CD34+ CD45- CD90+ CD105- CD146+) and vascular smooth muscle cells (CD31- CD34+ CD45- CD90+ CD105- CD146+). We also confirmed the output contains cells able to differentiate into adipogenic and osteogenic phenotypes. Our results show that cells isolated with the Celution and manually are equivalent.

DISCUSSION

Cells from adipose tissue can be processed by Celution within the time frame of a single surgical procedure. This system could provide a 'real-time' treatment setting that is cost-effective and safe.

[Surgical repair of type A aortic dissection with severe atherosclerosis; report of a case]

We report a case of type A aortic dissection with severe atherosclerosis. An 81-year-old man with acute type A aortic dissection was referred to our hospital. Computed tomography revealed DeBakey type II dissection with severe atherosclerosis. Ascending aortic replacement was performed urgently, and an autologous pericardium strip was placed in the lumen to prevent atheroembolization and to reinforce the friable atherosclerotic intima This technique was useful for avoiding cerebral vascular accidents. The patient was discharged on the 24th operative day with no complications.

Surface dose measurement in patients and physicians and effective dose estimation in patients during uterine artery embolisation

Surface dose monitoring in patients and physicians during 29 uterine artery embolisation (UAE) procedures was performed using photoluminescence dosemeters and thermo-luminescence dosemeters. Organ or tissue doses were measured with an anthropomorphic phantom using UAE exposure conditions averaged from the 29 cases, and effective doses were estimated for the patient. Entrance surface dose of the patients at the maximum dose position ranged from 121.5 to 1650 mGy. Estimated doses ranged from 3.16 to 43 mGy for the ovary and from 3.8 to 51.8 mGy for the uterus. The effective dose was 1.09-14.8 mSv. Monitored doses on the body surface of physicians were relatively high in the upper arm (5.41+/-1.52 to 163+/-17.25 microGy) and the hand and fingers (0.85+/-1.18 to 222+/-16.4 microGy).

p53AIP1 expression can be a prognostic marker in non-small cell lung cancer

AIMS

p53AIP1 is a potential mediator of p53-dependent apoptosis that is mutated in many kinds of carcinoma. To investigate the role of this gene for non-small cell lung cancer, we compared the relationship between p53AIP1 gene expression and clinicopathological status of lung cancer.

MATERIALS AND METHODS

Seventy samples from non-small cell lung cancer patients were obtained between 1997 and 2003. For quantitative evaluation of RNA expression by polymerase chain reaction (PCR) we used the Taqman PCR methods. Exons 5-8 of the p53 gene were analysed using PCR-single-stranded conformation polymorphism and sequenced for mutation analysis.

RESULTS

p53AIP1 gene expression levels in the lymph node metastasis-positive group were significantly lower than in the negative group (positive 35.1+/-83.9; negative 64.2+/-113.4; P=0.0486). The overall survival of the p53AIP1 low expression group was significantly worse than that of the p53AIP1 high expression group (P=0.0206). In the multivariate Cox proportional hazard model, p53AIP1 (P=0.0489) was the independent predictor for overall survival. When we investigated mutation analyses of the p53 gene, we could find several point mutations in 15.7% of all samples. However, there was no relationship between p53AIP1 expression and p53 status.

CONCLUSIONS

These data suggest that the p53AIP1 gene is important for non-small cell lung cancer progression and may be a possible prognostic marker.

The toxic conformation of the 42-residue amyloid beta peptide and its relevance to oxidative stress in Alzheimer's disease

Senile plaques in the brain of patients with Alzheimer's disease mainly consist of aggregates of amyloid beta peptides (Abeta42, Abeta40). Abeta42 is more neurotoxic than Abeta40. This review describes recent findings from a structural analysis of Abeta42 aggregates and discusses their relevance to neurotoxicity through the formation of radicals.

Fine needle aspiration cytology of high grade T-cell lymphomas in human T-lymphotropic virus type 1 carriers

We studied the fine needle aspiration (FNA) cytology of high grade peripheral T-cell lymphomas from eight human T-lymphotropic virus-1 (HTLV-1) positive patients. FNA smears from seven lymphomas showed a distinctive cytologic pattern with a dominance of rounded cells with irregular nuclei and a moderately basophilic cytoplasm. Irregular cells with a pale abundant cytoplasm were present in varying amounts. Some smears contained a few giant cells with cerebriform nuclei. In addition, plasma cells and eosinophils were found. Epithelioid cells were an inconstant finding. On histology these seven lymphomas were assigned to the pleomorphic medium-large cell subtype and all but one were of T-helper phenotype with rearrangements of the T-cell receptor. FNA smears from a lymph node in a patient with a previous histological diagnosis of lymphomatoid papulosis of the gingiva showed a monotonous pattern of large immunoblastic cells with some binucleated variants consistent with a diagnosis of high grade immunoblastic lymphoma, which was confirmed histologically. Our results show that peripheral T-cell lymphomas from HTLV-1 positive patients have cytological patterns which are distinctive enough to allow a conclusive diagnosis of high grade T-cell lymphoma. However, we do not think that the cytology of HTLV-1 positive lymphomas can be differentiated from that of virus-unrelated high grade T-cell lymphomas.

Short Communication: A Positive Relationship Between the First Ovulation Postpartum and the Increasing Ratio of Milk Yield in the First Part of Lactation in Dairy Cows

The aim of the present study was to examine the relationship between characteristics of the lactation curve, on the basis of daily milk yield, and ovulation within 3 wk postpartum as an indicator of early return to luteal activity in dairy cows. Lactation records from 46 lactating Holstein cows between calving and 305 d postpartum were studied. Milk samples were collected twice weekly between d 7 and 100 for later determination of progesterone concentrations. Occurrence of an early first ovulation was determined by an increase in milk progesterone by 3 wk after calving. Milk yield was recorded daily until 305 d postpartum, and average yield was calculated weekly. The lactation curve was characterized by 8 indices on the basis of the weekly average of milk yield as follows: a) first-week milk yield; b) peak milk yield; c) actual 305-d milk yield; d) peak week; e) difference in milk yield between the first week and peak week; f) difference in milk yield between the peak week and last week (43rd week postpartum); g) ratio of increase in milk yield between wk 1 and the week of peak yield; and h) ratio of decline in milk yield between the week of peak yield and the last week. Indices g and h were calculated as linear. The number of cows having ovulated by 3 wk postpartum was 22 (47.8%). The resumption of ovarian cycles with normal luteal phases occurred earlier in ovular cows than in anovular cows (32.0 d vs. 57.1 d). Although total milk yield did not differ between ovular and anovular cows, the ratio of increase in milk yield from the first week to the peak week (index g) in ovular cows was smaller compared with that of anovular cows (1.71 vs. 2.54). In addition, the ratio of increase in milk yield from the first week to the third week postpartum was greater in anovular cows by 3 wk postpartum (ovular = 1.43 +/- 0.23 vs. anovular = 2.32 +/- 0.29). In conclusion, the present study demonstrates that a greater increasing ratio of milk yield during early lactation may delay resumption of ovarian cycles after parturition. Therefore, this study is the first to demonstrate statistically that a smaller increasing ratio of milk yield (index g) during early lactation may have a beneficial effect on the first ovulation by 3 wk postpartum.

Protective effect of edaravone in inner-ear barotrauma in guinea pigs

OBJECTIVE

The purpose of this study was to determine the protective effect of edaravone, a free radical scavenger, on inner-ear barotrauma (IEB) in guinea pigs, based on a hypothesis implicating free radicals in the development of IEB.

MATERIALS AND METHODS

One hundred and twenty-five guinea pigs were divided into a control group and a pretreatment group. After auditory brainstem response (ABR) testing, the pretreatment group received 9.0 mg/kg intraperitoneal edaravone. Animals were exposed to pressure loading and then to further ABR testing.

RESULTS

The incidence of IEB was 62.7 per cent in the control group and 42.9 per cent in the pretreatment group (p<0.01). The distributions of threshold elevation in the control group were 37.3 per cent (for 10 dB or less), 21.3 per cent (for 20-30 dB), 18.0 per cent (for 40-60 dB) and 23.4 per cent (for 70 dB or more), and those in the pretreatment group were 57.1 per cent, 19.1 per cent, 14.3 per cent and 9.5 per cent, for the same respective decibel levels (p<0.01).

CONCLUSIONS

These results suggest that protective treatment with edaravone can significantly reduce both the incidence of IEB and the severity of the resultant ABR threshold elevation.

Patterns of masseter muscle activities during sleep in guinea pigs

Basic neurophysiological mechanisms for sleep bruxism remain unknown. Analyses of masseter muscle activity during sleep in guinea pigs have shown that the duration and activity of masseter bursts differ between non-rapid eye movement (NREM) and rapid eye movement (REM) sleep and that some repetitive burst episodes do occur. Furthermore, masseter bursts occurred in association with a transient heart rate increase. These results suggest that various patterns of masseter bursts occur in association with transient arousal activity during sleep in guinea pigs.

A mobile-phone based telecare system for the elderly

This study examined the use of telecommunications for home health care and described an alternative telemedicine framework. The framework aims to transmit small but sufficient amounts of data for daily monitoring of residential subjects' basic health status. We tested the remote monitoring of heart rate and respiration. The system was tested in real home-visit rehabilitation environments and was found to be useful both for the therapist and the patients in planning and evaluating daily rehabilitation training.

Differences in the histological findings, phenotypic marker expressions and genetic alterations between adenocarcinoma of the gastric cardia and distal stomach

Adenocarcinoma of the gastric cardia (C-Ca) is possibly a specific subtype of gastric carcinoma. The purpose of this study was to clarify the differences in the clinicopathological characteristics between C-Ca and adenocarcinoma of the distal stomach (D-Ca), and also the differences in the expressions of gastric and intestinal phenotypic markers and genetic alterations between the two. The clinicopathological findings in 72 cases with C-Ca were examined and compared with those in 170 cases with D-Ca. The phenotypic marker expressions examined were those of human gastric mucin (HGM), MUC6, MUC2 and CD10. Furthermore, the presence of mutations in the APC, K-ras and p53 genes and the microsatellite instability status of the tumour were also determined. C-Ca was associated with a significantly higher incidence of differentiated-type tumours and lymphatic vessel invasion (LVI) as compared with D-Ca (72.2 vs 48.2%, P=0.0006 and 72.2 vs 55.3%, P=0.0232, respectively). Oesophageal invasion by the tumour beyond the oesophago-gastric junction (OGJ) was found in 56.9% of cases with C-Ca; LVI in the area of oesophageal invasion was demonstrated in 61% of these cases. Also, LVI was found more frequently in cases of C-Ca with oesophageal invasion than in those without oesophageal invasion (82.9 vs 58.1%, P=0.0197). The incidence of undifferentiated-type tumours was significantly higher in cases with advanced-stage C-Ca than in those with early-stage C-Ca (5 vs 36.5%, P=0.0076). A significantly greater frequency of HGM expression in early-stage C-Ca and significantly lower frequency of MUC2 expression in advanced-stage C-Ca was observed as compared with the corresponding values in cases of D-Ca (78.9 vs 52.2%, P=0.0402 and 51.5 vs 84.6%, P=0.0247, respectively). Mutation of the APC gene was found in only one of all cases of C-Ca, and the frequency of mutation of the APC gene was significantly lower in cases of C-Ca than in those of D-Ca (2.4 vs 20.0%, P=0.0108). The observations in this study suggest that C-Ca is a more aggressive tumour than D-Ca. The differences in biological behavior between C-Ca and D-Ca may result from the different histological findings in the wall of the OGJ and the different genetic pathways involved in the carcinogenesis.

Flexible solar-cell from zinc oxide nanocrystalline sheets self-assembled by an in-situ electrodeposition process

Zinc oxide nanocrystalline sheets were self-assembled on a flexible polymer substrate to act as the electrode of dye-sensitized solar cells by an in situ-construction electrodeposition process. It was discovered that the nanosheet-based solar cell exhibited better performance than a nanoparticle-based solar cell or a well-oriented nanowire-based solar cell. The nanosheet microstructure has advantages which include the depression of loss during photoelectron transport, the increase of dye compound adsorption, and the enhance of incident light capture. As a result, the performance of dye-sensitized solar cells can be obviously improved. This success provides a feasible bottom-up approach for integrating a solar cell together with nanodevices and microcircuits on a flexible substrate which can work with self-supplied solar energy.

Solvent Effect on Intramolecular Electron Transfer Rates of Mixed-Valence Biferrocene Monocation Derivatives

Intramolecular electron transfer (ET) rates in various solvents of mixed-valence biferrocene monocation (Fe(II), Fe(III)) and the 1',1' ''-diiodo and 1',1' ''-diethyl derivatives (respectively abbreviated as BFC(+), I(2)BFC(+), and Et(2)BFC(+)) were determined by means of the spin-lattice relaxation times of the protons, taking into account the local magnetic field fluctuation caused by the electron hopping between the two ferrocene units. We also determined the ET rates of a mixed-valence diferrocenylacetylene monocation (DFA(+)) in order to examine the effect of the insertion of an acetylene bridge between the two ferrocene units. The insertion of the bridge decreased the ET rate, while the effect of substitution on the cyclopentadienyl rings on the rate was minor. The observed rates for each mixed-valence monocation in various solvents did not correlate with the reorganization energies, but we did find a significant contribution of the solvent dynamics. The observed rates were considerably higher than those expected on the basis of the Sumi-Marcus-Nalder model in which the solvents were regarded as dielectric continua. The slope of the logarithm plot of the pre-exponential factors in various solvents for each mixed-valence monocation versus the inverse of the longitudinal dielectric relaxation times of the solvents was significantly smaller than unity, and the slope for DFA(+) was larger than those for BFC(+), I(2)BFC(+), and Et(2)BFC(+). These results were ascribed to a partial contribution of the dielectric friction to the dynamics along the solvent coordinate; the extent of the contribution decreased with a reduction in the ET distance. For the dynamics along the solvent coordinate of the ET reactions in methanol, the observed rates indicated an important contribution by the minor dielectric relaxation components with faster relaxation times, rather than the major component with an extraordinarily long relaxation time.

Surface precipitation of highly porous hydrotalcite-like film on Al from a zinc aqueous solution

A hydrotalcite-like film has been successfully deposited on an Al-bearing glass substrate based on an interface reaction between an Al layer and a zinc aqueous solution. The film selectively grew on the Al surface but not on the glass surface. The film on Al was composed of layered nanosheets of a hydrotalcite-like compound containing Al and Zn. Comparably, deposits on the plastic surface and precipitates in solution were wurzite-type ZnO with various morphologies depending upon the preparation conditions. At low supersaturation degrees, single crystals and superstructures of Zn-Al hydrotalcite were also obtained. This porous hydrotalcite film has a potential application as catalyst supports, environmental materials, or matrixes for hydrotalcite-based nanocomposite films. Using Al as a reaction interface makes it easy to coat porous hydrotalcites on a series of matrix materials varying in shapes and properties, which is important for achieving practical applications. In addition, the method developed should be widely applicable to other systems for the preparation of porous or oriented hydrotalcite-like thin films by an appropriate combination of divalent/trivalent solution-substrate systems.