Transient receptor potential ankyrin 1 agonists improve intestinal transit in a murine model of postoperative ileus

BACKGROUND

Stimulation of transient receptor potential ankyrin 1 (TRPA1), which abundantly expressed in enterochromaffin cells (ECC), has been reported to exert apparently contradictory results in in vitro contractility and in vivo gastrointestinal (GI) transit evaluations. The pharmaceutical-grade Japanese traditional medicine daikenchuto (TU-100) has been reported to be beneficial for postoperative ileus (POI) and accelerate GI transit in animals and humans. TU-100 was recently shown to increase intestinal blood flow via stimulation of TRPA1 in the epithelial cells of the small intestine (SI).

METHODS

The effects of various TRPA1 agonists on motility were examined in a manipulation-induced murine POI model, in vitro culture of SI segments and an ECC model cell line, RIN-14B.

KEY RESULTS

Orally administered TRPA1 agonists, aryl isothiocyanate (AITC) and cinnamaldehyde (CA), TU-100 ingredients, [6]-shogaol (6S) and γ-sanshool (GS), improved SI transit in a POI model. The effects of AITC, 6S and GS but not CA were abrogated in TRPA1-deficient mice. SI segments show periodic peristaltic motor activity whose periodicity disappeared in TRPA1-deficient mice. TU-100 augmented the motility. AITC, CA and 6S increased 5-HT release from isolated SI segments and the effects of all these compounds except for CA were lost in TRPA1-deficient mice. 6S and GS induced a release of 5-HT from RIN-14B cells in a dose- and TRPA1-dependent manner.

CONCLUSIONS & INFERENCES

Intraluminal TRPA1 stimulation is a potential therapeutic strategy for GI motility disorders. Further investigation is required to determine whether 5-HT and/or ECC are involved in the effect of TRPA1 on motility.

Isolation of a new lytic enzyme for hiochi bacteria and other lactic acid bacteria

A microorganism producing a lytic enzyme preparation that could rapidly lyse bacterial cells such as hiochi bacteria and other lactic acid bacteria was screened. The microorganism was identified as Streptomyces fulvissimus. The enzyme produced by this organism lysed boil-denatured cells quicker than intact cells of hiochi bacteria. A mutant strain of S. fulvissimus producing the enzyme exhibiting high activity against intact cells of hiochi bacteria was screened on plates, containing intact cells inactivated with UV irradiation. The optimal pH for lytic activity against intact cells of the hiochi bacterium Lactobacillus casei S-4 was from 3.5 to 4.0, and the optimum temperature was close to 50 degrees C. This enzyme activity was stable between pH 3.5 and pH 8.0 and up to 60 degrees C. The enzyme exhibits N-acetyl glucosaminidase and muramidase activities. The effects of adjusting the pH and using different inducers for enzyme production were investigated. Chitin was the most effective inducer of enzyme production. Intact DNA was easily isolated from the cells of many lactic acid bacteria following lysis with the enzyme. It is thought that this enzyme will be a good biotechnological tool.

The effects of flumazenil on sleepiness, task performance and nocturnal sleep after anesthesia with midazolam

The purpose of the present study was to clarify the changes in psychophysiological functions after anesthesia with midazolam (intravenous (i.v.) benzodiazepine anesthetic) and to examine the ability of flumazenil (benzodiazepine antagonist) to prevent the adverse effects of anesthesia with midazolam. Clinical dose of midazolam (0.1 mg/kg i.v.) was administered to seven healthy volunteers and either flumazenil (0.3 mg i.v.) or saline was injected at the end of the anesthesia. After anesthesia with midazolam, subjective sleepiness and euphoria increased significantly, but these changes were not observed when flumazenil was administered. In addition, sleep latency was prolonged and sleep efficiency decreased significantly after midazolam anesthesia with and without flumazenil. Slow wave sleep decreased significantly only by co-administration of flumazenil.

Changes in subjective sleepiness, subjective fatigue and nocturnal sleep after anaesthesia with propofol

The purpose of this study was to clarify the changes in psycho-physiological functions after anaesthesia with propofol (PF). The subjects were seven healthy male volunteers and the duration of the anaesthesia was 1 h (14:00-15:00 h). The plasma concentration of PF immediately decreased after the anaesthesia. The subjective sleepiness and VAS (visual liner analogue scale) scores (i.e. effort to do something) increased significantly at 20 min after the anaesthesia. However, these changes were improved at 80 min after the anaesthesia. The sleep latency at the nocturnal sleep 8 h after the anaesthesia was prolonged significantly, but the other parameters including the distributions of stage 3 + 4 and the rapid eye movement 'REM' stage were not changed.

[People's functional evaluations, perception of fairness, and commitment to the state]

A questionnaire was mailed to a random sample of 3,000 people who were older than 20, and 993 responded. The questionnaire was designed to measure the respondent's functional evaluations of Japan's political branches (the Diet, the Government, and its administrative agencies), its perceived fairness, his/her emotional and utilitarian commitment to Japan, and the political party he/she supported. Based on the fairness-bond theory model, we hypothesized that positive evaluations of political branches would increase perceived fairness, which in turn leaded to a stronger commitment. Path analysis indicated that the hypothesis was partially supported, and that functional evaluations of political branches had a direct effect on the commitment. It was also found that politically conservative respondents showed more positive evaluations and stronger commitment to Japan than liberal ones, suggesting political attitudes as a moderator variable for the fairness mediation.

[Multiple goals in conflict resolution: their antecedents and effects upon tactical preference]

The multiple goals theory of conflict management (Ohbuchi & Tedeschi, in press) postulated that participants in a conflict pursue to achieve resource goals (economic and personal resources) and social goals (relationship, identity, justice, and power-hostility). The hypotheses based on this theory were examined by the episode method, in which 207 university students were asked to rate their recent experiences of interpersonal conflicts in terms of participants' attributes, goals, and tactics. More than 80% of the subjects answered that they were motivated to achieve multiple goals in their attempts to resolve the conflicts. Social goals were found to be more strongly activated, and economic resource goals were least strongly activated. Regression analyses revealed that the effects of participants' attributes on tactical preference were mediated by goals.

Empathy and aggression: effects of self-disclosure and fearful appeal

On the basis of the familiarity-empathy assumption that self-disclosure evokes empathy for the speaker, it was predicted that a victim's self-disclosure would inhibit aggression against the victim. Female Japanese subjects were asked to give electric shocks to a female victim who disclosed information about herself, was not given an opportunity to do so, or rejected disclosure. Independently of self-disclosure, another empathy arousal was introduced, that is, whether or not the victim expressed her fear of shocks before they were delivered. Consistent with our hypothesis, subjects selected less severe shocks when the victim disclosed information about herself than when she was not given an opportunity to do so or when she rejected self-disclosure. The victim's expression of fear was also very effective in reducing subjects' aggression, suggesting that drawing subjects' attention to the victim's negative emotional state evoked empathy for her and reduced their aggression.

Apology as aggression control: its role in mediating appraisal of and response to harm

Two studies examined the effects of an apology on a victim's aggression and explored the psychological mechanisms underlying such effects. In Study 1, female undergraduates were psychologically harmed and then received an apology by another female student. In Study 2, male undergraduates were asked to role play a victim in a hypothetical harm situation. Results indicate that when the harm-doers apologized, as opposed to when they did not, the victim-subjects refrained from severe aggression against them. Regression analyses suggested that such aggression-inhibitory effects of an apology were mediated by impression improvement, emotional mitigation, and reduction in desire for an apology within the victims. It was also found that when the harm was severe, such effects of an apology on aggression were attenuated. The more severe the harm is, the more extensive of an apology may be needed to alleviate the victim's anger and aggression.

Apology as aggression control: Its role in mediating appraisal of and response to harm

Two studies examined the effects of an apology on a victim's aggression and explored the psychological mechanisms underlying such effects. In Study 1, female undergraduates were psychologically harmed and then received an apology by another female student. In Study 2, male undergraduates were asked to role play a victim in a hypothetical harm situation. Results indicate that when the harm-doers apologized, as opposed to when they did not, the victim-subjects refrained from severe aggression against them. Regression analyses suggested that such aggression-inhibitory effects of an apology were mediated by impression improvement, emotional mitigation, and reduction in desire for an apology within the victims. It was also found that when the harm was severe, such effects of an apology on aggression were attenuated. The more severe the harm is, the more extensive of an apology may be needed to alleviate the victim's anger and aggression.

[Motives and interpersonal functions of aggression]

In this review, the author theoretically and empirically examined motives and interpersonal functions of aggression. A factor-analysis of Averill's questionnaire items on anger revealed that motives involved in aggressive responses were clustered into two groups: the hostile and the instrumental. It was also clarified that an individual is likely to engage in aggression particularly when some hostile motives are evoked. Concerning the interpersonal functions, the author proposed that aggression might serve four principal goals. (1) Aggression can be generated as an avoidance response to an aversive stimulus, such as frustration, annoyance, or pain, and so on. It depends on the severity of the stimulus. It was however emphasized that aggression is also mediated by social cognition, such as an attribution of intent to a harm-doer. (2) Aggression can be used as a means of coercing the other person into doing something. An individual is likely to use such a power strategy if he/she is lacking in self-confidence or a perspective for influencing the target person by more peaceful strategies. (3) Aggression can be interpreted as a punishment when it is directed toward a transgressor. In this case, aggression is motivated by restoration of a social justice, and thus its intensity is determined by the perceived moral responsibility of the transgressor. Further, it was indicated that aggression is intensified if it is justified as a sanctional conduct against the immoral. (4) Aggression can be also evoked when an individual's social identity is threatened. It was suggested that impression management motives are involved in aggression by an unexpected finding that the presence of audience or the identifiability rather facilitated retaliative aggression. The aggression-inhibition effect of apology was also explained in terms of impression management. In conclusion, it was presented that aggression is a behavioral strategy as an attempt to resolve interpersonal conflicts including physical or psychological annoyance, the other person's disobedience, perceived injustice, and a threat to one's social identity. Whether one's aggression is performed or not depends on a number of intra- and inter-personal determinants, particularly on social cognitive processes such as attribution, inference, prediction and other judgements.

The image forming process of photoconductive toner

To obtain a good image using a photoconductive toner, the potential acceptability of the photoconductive toner layer may exceed 2.5 or preferably 3.5 V/g/m(2) and the residual potential after exposure may not exceed 20 V. The potential acceptability increases with toner sprinkling density and approaches a definite value. The initial potential increases proportional to the toner sprinkling density and the residual potential increases superlinearly. The residual potential per unit initial potential has a minimum against a definite value of toner sprinkling density, and the photoconductive toner layer has desirable potential acceptability and residual potential around this value, so that a good image is obtained. In general this value lies between 80-120 g/m(2). The electrostatic powder sprinkling method gives higher potential acceptability and lower dark decay rate than the post charging method, but no significant difference in light sensitivity. A good developing result is obtained with an air jet which has a narrow velocity distribution and is blown against the photoconductive layer at an angle near 90 degrees . Air velocity between 15-20 m/sec just on the layer gives a good result.