In vivo evaluation of pharmacokinetic drug-drug interactions between fluorinated pyrimidine anticancer drugs, 5-fluorouracil and capecitabin, and an anticoagulant, warfarin.

Warfarin is a common anticoagulant and has demonstrated interactions with several drugs. Among them, as a serious adverse event, a case of death due to the enhanced warfarin action owing to its combined use with a fluoropyrimidine anticancer drug has been reported, but the detailed mechanism has not been elucidated.Some reports have advocated that fluorinated pyrimidine anticancer drugs reduce cytochrome P450 2C9 expression, leading to the enhanced pharmacological effects of warfarin.The purpose of this study was to clarify the mechanisms of drug-drug interactions between warfarin and 5-fluorouracil (5-FU) and capecitabine in vivo using rats. Rats were administered warfarin in combination with 5-FU (15 mg/kg/d) or capecitabine (15 mg/kg/d) for 7 d. Prothrombin time (PT) and activated partial thromboplastin time were significantly prolonged in the warfarin plus 5-FU or capecitabine groups compared with those in the warfarin alone group. No significant difference was observed in the area under the plasma concentration-time curve of the warfarin alone group compared with the warfarin with 5-FU or capecitabine groups.These data suggest that the enhancement of warfarin efficacy caused by the combination of 5-FU or capecitabine was due to a pharmacological interaction rather than a pharmacokinetic interaction.

Troglitazone-Induced Autophagic Cytotoxicity in Lung Adenocarcinoma Cell Lines.

Lung cancer is the leading cause of cancer-related deaths worldwide. Troglitazone (TGZ), a peroxisome proliferator-activated receptor gamma (PPARγ) ligand, is a potential antitumor agent. However, the action mechanism of TGZ in lung adenocarcinoma cells has not been completely elucidated. To assess this mechanism and the anticancer effects of TGZ in human lung adenocarcinoma cell lines (A549 and H1975), we investigated the involvement of PPARγ, apoptosis, the mitogen-activated protein kinase (MAPK) pathway, protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway, and autophagy. Cell viability was measured using fluorescence-based assays. Apoptotic cells were detected by Hoechst 33342 and Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) double staining; protein expression was detected by Western blotting. TGZ inhibited cell proliferation in a dose-dependent manner in both cell lines, and the effect was not suppressed by a PPARγ inhibitor. Additionally, TGZ increased apoptotic cell number and upregulated p38 and c-Jun N-terminal kinase (JNK) phosphorylation; however, p38 and JNK inhibitors did not block TGZ-mediated inhibition of cell proliferation in either cell line. TGZ also upregulated extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation, whereas an ERK1/2 inhibitor enhanced TGZ-mediated cytotoxicity in A549 cells. Additionally, TGZ increased LC3-II expression, and chloroquine (an autophagy inhibitor) attenuated TGZ-mediated inhibition of cell proliferation. These findings suggest that TGZ-induced inhibition of cell proliferation is PPARγ independent. TGZ-mediated inhibition of cell proliferation was accompanied by apoptosis and independent of the MAPK signaling pathway. These results suggest that TGZ inhibits cell proliferation through autophagy-induced cytotoxicity. This study demonstrated that chemotherapy using TGZ may be effective for lung adenocarcinoma.

Telmisartan-Induced Cytotoxicity via G2/M Phase Arrest in Renal Cell Carcinoma Cell Lines.

Renal cell carcinoma (RCC) is the most common type of kidney cancer. Given that stage IV RCC is intractable, there is a need for a novel treatment strategy. We investigated the antitumor effects of telmisartan (TEL) and their underlying mechanisms in RCC, including their impact on apoptosis, Akt/mammalian target of rapamycin (mTOR) pathways, and the cell cycle using two human RCC cell lines: 786-O and Caki-2. Cell viability was detected via fluorescence-based assays. Cells were stained with Hoechst 33342 to observe chromatin condensation, and Western blotting was performed to analyze protein expression. The cell cycle was assessed using flow cytometry. Invasion and migration assays were performed using 24-well chambers. TEL induced cell death in a dose-dependent manner and increased the percentage of cells with high chromatin condensation and Bax/Bcl-2 ratio in both cell lines. TEL-induced cell death was attenuated by neither peroxisome proliferator-activated receptor-γ nor -δ inhibitors. Although TEL elevated c-Jun N-terminal kinase levels and p38 phosphorylation rates in Caki-2 cells, as well as extracellular signal-regulated kinase phosphorylation rates in 786-O cells, their inhibitors did not suppress TEL-induced cell death. TEL decreased Akt phosphorylation in 786-O cells and mTOR phosphorylation in both cell lines, increased the population of cells in the G2/M phase, and altered G2/M-related proteins in both cell lines. TEL moderately suppressed cell invasion and migration in 786-O and Caki-2 cells, respectively, and increased cell invasion in Caki-2 cells, suggesting a potential therapeutic role of TEL in RCC.

The role of the ventromedial prefrontal cortex in automatic formation of impression and reflected impression.

Previous neuroimaging studies demonstrated that ventromedial prefrontal cortex (vmPFC) activity reflects how much an individual positively views each person (impression). Here, we investigated whether the degree to which individuals think others positively view them (reflected impression) is similarly tracked by activity in the vmPFC by using fMRI and speed-dating events. We also examined whether activity of the vmPFC in response to the faces of others would predict the impression formed through direct interactions with them. The task consisted of three sessions: pre-speed-dating fMRI, speed-dating events, and post-speed-dating fMRI (not reported here). During the pre-speed-dating fMRI, each participant passively viewed the faces of others whom they would meet in the subsequent speed-dating events. After the fMRI, they rated the impression and reflected impression of each face. During the speed-dating events, the participants had 3-min conversations with partners whose faces were presented during the fMRI task, and they were asked to choose the partners whom they preferred at the end of the events. The results revealed that the value of both the impression and reflected impression were automatically represented in the vmPFC. However, the impression fully mediated the link between the reflected impression and vmPFC activity. These results highlight a close link between reflected appraisal and impression formation and provide important insights into neural and psychological models of how the reflected impression is formed in the human brain.

Focused attention meditation training modifies neural activity and attention: longitudinal EEG data in non-meditators.

Focused attention meditation (FAM) is a basic meditation practice that cultivates attentional control and monitoring skills. Cross-sectional studies have highlighted high cognitive performance and discriminative neural activity in experienced meditators. However, a direct relationship between neural activity changes and improvement of attention caused by meditation training remains to be elucidated. To investigate this, we conducted a longitudinal study, which evaluated the results of electroencephalography (EEG) during three-stimulus oddball task, resting state and FAM before and after 8 weeks of FAM training in non-meditators. The FAM training group (n = 17) showed significantly higher P3 amplitude during the oddball task and shorter reaction time (RT) for target stimuli compared to that of the control group (n = 20). Furthermore, a significant negative correlation between F4-Oz theta band phase synchrony index (PSI) during FAM and P3 amplitude during the oddball task and a significant positive correlation between F4-Pz theta band PSI during FAM and P3 amplitude during the oddball task were observed. In contrast, these correlations were not observed in the control group. These findings provide direct evidence of the effectiveness of FAM training and contribute to our understanding of the mechanisms underpinning the effects of meditation on brain activity and cognitive performance.

Current practices and factors affecting evidence-based occupational therapy practice for patients with dementia in Japan.

OBJECTIVE/BACKGROUND: The rapidly increasing incidence of patients with dementia in Japan is creating an urgent demand for evidence-based occupational therapy (EBOT), which has been reported to improve clinical efficacy. This study aimed to examine the current practice of EBOT for patients with dementia in Japan and clarify factors influencing its application. METHODS: We conducted an anonymous, self-administered questionnaire survey by mail. The participants were 432 occupational therapists treating patients with dementia at 432 designated medical institutions nationwide. Descriptive statistics were calculated, and multiple regression analysis was performed to clarify the factors influencing the present application of EBOT. RESULTS: The response rate was 31.3%. Among the participants, 46.3% responded 'somewhat frequently' or more (5, 6, and 7 on a 7-grade scale) to a question on the frequency of practice of EBOT. Using multiple regression analysis with the stepwise method, we selected the model with the highest degree of fit. This model extracted three factors, namely, ability to understand scientific papers, sufficiency of means of getting information, and availability of advice, which had standardized partial regression coefficients (ß) of 0.419, 0.214, and 0.158, respectively. CONCLUSIONS: The three factors extracted using the multiple regression analysis indicate that in order to encourage EBOT for patients with dementia, occupational therapists need to acquire reading comprehension skills, so that they can assess the quality of scientific papers. Furthermore, it is important to create environments where they have access to publications and can discuss research with superiors and colleagues.

In vitro and in vivo cytotoxicity of troglitazone in pancreatic cancer.

BACKGROUND: Troglitazone (TGZ) is a peroxisome proliferator-activated receptor gamma (PPARγ) agonist that has been investigated as a potential chemopreventive and chemotherapeutic agent. However, the antitumor efficacy and mechanisms of TGZ in pancreatic cancer have not been extensively investigated. This study was performed to investigate the in vitro and in vivo effects of TGZ against pancreatic cancer cell lines, as well as its action mechanisms in terms of PPARγ dependency and the Akt and mitogen-activated protein kinase (MAPK) pathways. We also evaluated the effects of TGZ on cell invasion and migration. METHODS: MIA Paca2 and PANC-1 human pancreatic cancer cell lines were used. Cell viability and caspase-3 activity were detected using fluorescent reagents, and chromatin condensation was observed after staining the cells with Hoechst 33342. Protein expression levels were detected by western blot analysis. Invasion and migration assays were performed using 24-well chambers. The in vivo antitumor effects of TGZ were investigated in nude mice inoculated with MIA Paca2 cells. Mice were orally administered TGZ (200 mg/kg) every day for 5 weeks, and tumor volumes were measured bi-dimensionally. RESULTS: TGZ showed dose-dependent cytotoxicity against both cell lines, which was not attenuated by a PPARγ inhibitor. Further, TGZ induced chromatin condensation, elevated caspase-3 activity, and increased Bax/Bcl-2 relative expression in MIA Paca2 cells. TGZ also increased phosphorylation of Akt and MAPK (ERK/p38/JNK) in both cell lines, and a JNK inhibitor significantly increased the viability of MIA Paca2 cells. TGZ moderately inhibited cell migration. Tumor growth in the MIA Paca2 xenograft model was inhibited by TGZ administration, while mouse body weights in the treated group were not different from those of the vehicle administration group. CONCLUSION: We demonstrated for the first time the in vivo antitumor effects of TGZ in pancreatic cancer without marked adverse effects. TGZ induced mitochondria-mediated apoptosis in MIA Paca2 cells, and its cytotoxic effects were PPARγ-independent and occurred via the JNK pathway. Our results indicate that TGZ is a potential approach for the treatment of pancreatic cancer and warrants further studies regarding its detailed mechanisms and clinical efficacy.

Effect of NaCl on ionic content and distribution in suspension-cultured cells of the halophyte Sonneratia alba versus the glycophyte Oryza sativa.

The effect of a high concentration of NaCl on the intra- (cytoplasmic matrix and vacuole) and extracellular (cell wall) distribution of Na, Cl, K, Mg, Ca, S, and P was investigated in suspension-cultured cells of the mangrove halophyte Sonneratia alba and compared to cultured cells of glycophytic rice (Oryza sativa). No significant differences were observed in ultrastructural features of cluster cells of both species cultured with and without 50mM NaCl. Quantitative X-ray microanalysis of cryosections of the cells cultured in the presence of 50mM NaCl showed that the Na concentration ([Na]) and Cl concentration ([Cl]) significantly increased in all three cell components measured. In S. alba, the [Na] was highest in the vacuole and lowest in the cytoplasmic matrix, while the [Cl] was highest in the cell wall and lowest in the cytoplasmic matrix. In O. sativa, however, the [Na] and [Cl] were highest in the cell wall, and the [Na] was lowest in the cytoplasmic matrix. Thus, the possible activities for Na and Cl transport from the cytoplasmic matrix into the vacuole were greater in S. alba than in O. sativa, suggesting that halophilic mangrove cells gain salt tolerance by transporting Na and Cl into their vacuoles. In O. sativa, the addition of NaCl to the culture medium caused no significant changes to the intracellular concentrations of various elements, such as K, P, S, Ca, and Mg, which suggests the absence of a direct relationship with the transport Na and Cl. In contrast, a marked decrease in the Ca concentration ([Ca]) in the cytoplasmic matrix and vacuole and an approximately two-fold increase in the P concentration ([P]) in the cytoplasmic matrix were found in S. alba, suggesting that the decrease in the [Ca] is related to the halophilic nature of S. alba (as indicated by the inward movement of Na(+) and Cl(-)). The possible roles of a Na(+)/Ca(2+) exchange mechanism in halophilism and the effect of the [P] on the metabolic activity under saline conditions are discussed.

An inverse relationship between allelopathic activity and salt tolerance in suspension cultures of three mangrove species, Sonneratia alba, S. caseolaris and S. ovata: development of a bioassay method for allelopathy, the protoplast co-culture method.

A bioassay method for allelopathy, the 'protoplast co-culture method' was developed to study the relationship between salt tolerance and allelopathy of three mangrove species, Sonneratia alba, S. caseolaris, and S. ovata. Plants of S. alba grow in the seaward-side high salinity region and plants of the latter two species grow in upstream-side regions of a mangrove forest, respectively. Effects of five sea salts (NaCl, KCl, MgCl2, MgSO4 and CaCl2) on the growth of the suspension cells of the latter two species were first investigated by a small-scale method using 24-well culture plates. S. ovata cells showed higher tolerance than S. caseolaris cells to NaCl and other salts, but were not as halophilic as S. alba cells. Protoplasts isolated from suspension cells were co-cultured with lettuce protoplasts in Murashige and Skoog's (MS) basal medium containing 1 µM 2,4-dichlorophenoxyacetic acid, 0.1 µM benzyladenine, 3% sucrose and 0.6-0.8 M osmoticum. S. caseolaris protoplasts had a higher inhibitory effect on lettuce protoplast cell divisions than S. alba protoplasts at any lettuce protoplast density, and the effect of S. ovata was intermediate between the two. These results were similar to those obtained from a different in vitro bioassay method for allelopathy, the 'sandwich method' with dried leaves. The inverse relationship between allelopathic activity and salt tolerance in suspension cells of Sonneratia mangroves is discussed.

Characterization of Pseudomonas stutzeri NT-I capable of removing soluble selenium from the aqueous phase under aerobic conditions.

Pseudomonas stutzeri strain NT-I was isolated from the drainage wastewater of a selenium refinery plant. This bacterium efficiently reduced selenate to elemental selenium without prolonged accumulation of selenite under aerobic conditions. Strain NT-I was able to reduce selenate completely at high concentrations (up to 10 mM) and selenite almost completely (up to 9 mM). In addition, higher concentrations of selenate and selenite were substantially reduced. Activity was observed under the following experimental conditions: 20-50°C, pH 7-9, and 0.05-20 g L(-1) NaCl for selenate reduction, and 20-50°C, pH 6-9, and 0.05-50 g L(-1) NaCl for selenite reduction. Under anaerobic conditions, selenate was reduced more rapidly, whereas selenite was not reduced at all. The high selenate- and selenite-reducing capability at high concentrations suggested that strain NT-I is suitable for the removal of selenium from high-strength industrial wastewater.

Synthesis, inhibitory effects on nitric oxide and structure-activity relationships of a glycosphingolipid from the marine sponge Aplysinella rhax and its analogues.

The novel glycosphingolipid, ß-D-GalNAcp(1-->4)[α-D-Fucp(1-->3)]-ß-D-GlcNAcp(1-->)Cer (A), isolated from the marine sponge Aplysinella rhax has a unique structure, with D-fucose and N-acetyl-D-galactosamine moieties attached to a reducing-end N-acetyl-D-glucosamine through an α1-->3 and ß1-->4 linkage, respectively. We synthesized glycolipid 1 and some non-natural di- and trisaccharide analogues 2-6 containing a D-fucose residue. Among these compounds, the natural type showed the most potent nitric oxide (NO) production inhibitory activity against LPS-induced J774.1 cells. Our results indicate that both the presence of a D-Fucα1-3GlcNAc-linkage and the ceramide aglycon portion are crucial for optimal NO inhibition.

Rhythmic synchronization tapping to an audio-visual metronome in budgerigars.

In all ages and countries, music and dance have constituted a central part in human culture and communication. Recently, vocal-learning animals such as parrots and elephants have been found to share rhythmic ability with humans. Thus, we investigated the rhythmic synchronization of budgerigars, a vocal-mimicking parrot species, under controlled conditions and a systematically designed experimental paradigm as a first step in understanding the evolution of musical entrainment. We trained eight budgerigars to perform isochronous tapping tasks in which they pecked a key to the rhythm of audio-visual metronome-like stimuli. The budgerigars showed evidence of entrainment to external stimuli over a wide range of tempos. They seemed to be inherently inclined to tap at fast tempos, which have a similar time scale to the rhythm of budgerigars' natural vocalizations. We suggest that vocal learning might have contributed to their performance, which resembled that of humans.