RELATIONSHIPS BETWEEN IDENTITY AND ACADEMIC MOTIVATION.

This study examined university students' academic motivation, focusing on individual differences in their sense of identity. The participants were 109 female Japanese students from two private universities (age range = 19-22 yr., M = 19.3, SD = 0.6). They completed four scales: the Multidimensional Ego Identity Scale, the Scale of Students' Attitude Toward Their Classes, the Academic Motivation Inventory, and the Scale of Lecture Self-Evaluation. Correlational analyses assessed the relationships between subscales. Then, path analysis was conducted to evaluate whether sense of identity affected attitude toward classes, academic motivation, and lecture self-evaluation. Differences particularly in psychosocial identity and self-identity accounted for significant variance in the students' attitudes toward classes, academic motivation, and lecture self-evaluation.

Comparative study of the hydrolytic metabolism of methyl-, ethyl-, propyl-, butyl-, heptyl- and dodecylparaben by microsomes of various rat and human tissues.

Hydrolytic metabolism of methyl-, ethyl-, propyl-, butyl-, heptyl- and dodecylparaben by various tissue microsomes and plasma of rats, as well as human liver and small-intestinal microsomes, was investigated and the structure-metabolic activity relationship was examined. Rat liver microsomes showed the highest activity toward parabens, followed by small-intestinal and lung microsomes. Butylparaben was most effectively hydrolyzed by the liver microsomes, which showed relatively low hydrolytic activity towards parabens with shorter and longer alkyl side chains. In contrast, small-intestinal microsomes exhibited relatively higher activity toward longer-side-chain parabens, and showed the highest activity towards heptylparaben. Rat lung and skin microsomes showed liver-type substrate specificity. Kidney and pancreas microsomes and plasma of rats showed small-intestinal-type substrate specificity. Liver and small-intestinal microsomal hydrolase activity was completely inhibited by bis(4-nitrophenyl)phosphate, and could be extracted with Triton X-100. Ces1e and Ces1d isoforms were identified as carboxylesterase isozymes catalyzing paraben hydrolysis by anion exchange column chromatography of Triton X-100 extract from liver microsomes. Ces1e and Ces1d expressed in COS cells exhibited significant hydrolase activities with the same substrate specificity pattern as that of liver microsomes. Small-intestinal carboxylesterase isozymes Ces2a and Ces2c expressed in COS cells showed the same substrate specificity as small-intestinal microsomes, being more active toward longer-alkyl-side-chain parabens. Human liver microsomes showed the highest hydrolytic activity toward methylparaben, while human small-intestinal microsomes showed a broadly similar substrate specificity to rat small-intestinal microsomes. Human CES1 and CES2 isozymes showed the same substrate specificity patterns as human liver and small-intestinal microsomes, respectively.

The safety of rapid administration of enteral nutrition in acute stroke patients.

BACKGROUND/AIMS: Early initiation of enteral nutrition (EN) is recommended for acute stroke patients, but it is time-consuming. Reducing EN administration time without increasing the frequency of complications is a worthwhile goal. We aimed to determine whether this goal was feasible. METHODS: Consecutive acute stroke patients with severe dysphagia within 72 h of hospital admission who received EN were retrospectively enrolled. Patients were classified into two groups (Rapid administration group: 100 mL/5 min on days 1-3 after stroke onset and 200 mL/30 min on days 4-7, Conventional administration group: 100 mL/h on days 1-3 and 200 mL/h on days 4-7). RESULTS: Among 118 consecutive acute stroke patients, 71 patients [median age, 77 (68-82) years; 37 (52%) males] were enrolled. The baseline clinical characteristics of the rapid administration group (45 patients) and the conventional administration group (26 patients) did not differ. The total duration of EN administration in the first week after stroke onset was significantly longer in the conventional vs. rapid administration group [21 (15-21) h vs. 6 (2-8) h, p < 0.01]. There were no significant differences in the frequency of diarrhea (42% vs. 42%, p = 1.00), vomiting (0% vs. 7%, p = 0.29), or pneumonia (15% vs. 7%, p = 0.41). There was also no difference in the percentage of patients with one or more complications (54% vs. 49%, p = 0.81). CONCLUSIONS: Rapid administration of EN is safe and has the potential to decrease the time required for EN feeding.

Comparative study of hydrolytic metabolism of dimethyl phthalate, dibutyl phthalate and di(2-ethylhexyl) phthalate by microsomes of various rat tissues.

Phthalates are used in food packaging, and are transferred to foods as contaminants. In this study, we examined the hydrolytic metabolism of dimethyl phthalate (DMP), dibutyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP) by rat tissue microsomes. We found that carboxylesterase and lipase contribute differently to these activities. When DMP, DBP and DEHP were incubated with rat liver microsomes, DBP was most effectively hydrolyzed to the phthalate monoester, followed by DMP, and the activity toward DEHP was marginal. In contrast, small-intestinal microsomes exhibited relatively higher activity toward long-side-chain phthalates. Pancreatic microsomes showed high activity toward DEHP and DBP. Liver microsomal hydrolase activity toward DMP was markedly inhibited by bis(4-nitrophenyl)phosphate, and could be extracted with Triton X-100. The activity toward DBP and DEHP was partly inhibited by carboxylesterase inhibitor, and was partly solubilized with Triton X-100. Ces1e, Ces1d and Ces1f expressed in COS cells exhibited the highest hydrolase activity toward DBP, showing a similar pattern to that of liver microsomes. Ces1e showed activity towards DMP and DEHP. Pancreatic lipase also hydrolyzed DBP and DEHP. Thus, carboxylesterase and lipase contribute differently to phthalate hydrolysis: short-side-chain phthalates are mainly hydrolyzed by carboxylesterase and long-side-chain phthalates are mainly hydrolyzed by lipase.

Cytochrome P450-inhibitory activity of parabens and phthalates used in consumer products.

The in vitro cytochrome P450 (CYP)-inhibitory effects of 11 parabens and 7 phthalates used in consumer products, as well as their hydrolytic metabolites, were investigated, using rat liver microsomes as an enzyme source. The effects on individual CYP isozymes were evaluated by assaying inhibition of activities towards specific substrates, i.e., ethoxyresorufin O-dealkylase (EROD), methoxyresorufin O-dealkylase (MROD), pentoxyresorufin O-dealkylase (PROD), 7-benzyloxy-4-trifluoromethylcoumarin dealkylase (BFCD), 7-methoxy-4-trifluoromethylcoumarin dealkylase (MFCD) and 7-ethoxy-4-trifluoromethylcoumarin dealkylase (EFCD) activities. These activities were dose-dependently inhibited, most potently by medium-side-chain parabens (C6-9) and phthalates (C4-6), and less potently by shorter- and longer-side-chain esters. The hydrolytic product of parabens, 4-hydroxybenzoic acid, was not inhibitory, while those of phthalates, phthalic acid monoesters, showed lower inhibitory activity than the parent phthalates. Parabens showed relatively potent inhibition of MFCD activity, considered to be mainly due to CYP2C, and phthalates showed relatively potent inhibition of PROD activity, considered to be mainly due to CYP2B.

Feasibility of using magnetic resonance imaging as a screening tool for acute stroke thrombolysis.

BACKGROUND: Feasibility of performing MRI first for suspected hyperacute stroke patients in real-world practice has not been fully examined. Moreover, most past studies of reducing door-to-needle time (DNT) in intravenous thrombolysis were conducted using CT. The aim of this study was to evaluate the feasibility of an MRI-first policy and examine the effects of a quality improvement (QI) process for reducing DNT using MRI. METHODS: From January 2014 to August 2015, consecutive acute stroke patients who were treated with thrombolysis were prospectively enrolled into the present study. In principle, multimodal 1.5T-MRI was performed first for patients with suspected acute stroke. A step-by-step QI process for decreasing DNT, including prenotification by the emergency medical service, limiting the MRI sequence, and introduction of a rapid examination tool, was also implemented during this period. Time metrics for thrombolysis were compared between specific time periods. RESULTS: A total of 73 patients (27 women; median age 74years) were included in the present study. More than 80% of the patients were screened with MRI. More patients were managed with the MRI-first policy in the late phase (p=0.018). DNT (83min in the early phase, 68min in the middle phase, and 54min in the late phase, p<0.001) was significantly reduced across phases. The percentage of patients with DNT<60min increased significantly across time periods (p<0.001). CONCLUSION: An MRI-first policy was feasible, and DNT was substantially reduced with a QI process. This process may be applicable to other hospitals.

Hydrolytic metabolism of phenyl and benzyl salicylates, fragrances and flavoring agents in foods, by microsomes of rat and human tissues.

Salicylates are used as fragrance and flavor ingredients for foods, as UV absorbers and as medicines. Here, we examined the hydrolytic metabolism of phenyl and benzyl salicylates by various tissue microsomes and plasma of rats, and by human liver and small-intestinal microsomes. Both salicylates were readily hydrolyzed by tissue microsomes, predominantly in small intestine, followed by liver, although phenyl salicylate was much more rapidly hydrolyzed than benzyl salicylate. The liver and small-intestinal microsomal hydrolase activities were completely inhibited by bis(4-nitrophenyl)phosphate, and could be extracted with Triton X-100. Phenyl salicylate-hydrolyzing activity was co-eluted with carboxylesterase activity by anion exchange column chromatography of the Triton X-100 extracts of liver and small-intestinal microsomes. Expression of rat liver and small-intestinal isoforms of carboxylesterase, Ces1e and Ces2c (AB010632), in COS cells resulted in significant phenyl salicylate-hydrolyzing activities with the same specific activities as those of liver and small-intestinal microsomes, respectively. Human small-intestinal microsomes also exhibited higher hydrolyzing activity than liver microsomes towards these salicylates. Human CES1 and CES2 isozymes expressed in COS cells both readily hydrolyzed phenyl salicylate, but the activity of CES2 was higher than that of CES1. These results indicate that significant amounts of salicylic acid might be formed by microsomal hydrolysis of phenyl and benzyl salicylates in vivo. The possible pharmacological and toxicological effects of salicylic acid released from salicylates present in commercial products should be considered.