Maternal separation in early life impairs tumor immunity in adulthood in the F344 rat

Neonatal stress alters the hypothalamic-pituitary-adrenal (HPA) axis in rodents, such that, when these animals are exposed to stress as adults they hypersecrete corticosterone. Given that glucocorticoids are immunosuppressive, we examined the impact of maternal separation on HPA axis reactivity, natural killer (NK) cytotoxicity, and tumor growth in Fischer 344 rats following chronic restraint stress in adulthood. Pups underwent a chronic stress protocol whereby they were separated from their dams for 3 h on postnatal days 1-21. In adulthood, corticosterone responses were assessed following exposure to chronic (6 days for 10 h) restraint stress. Rats allocated to the chronic stress condition were inoculated with MADB106 tumor cells on day 4 of the restraint protocol. Blood was assessed for NK cytotoxicity on the final day of the chronic restraint protocol, and tumor colonization was assessed 3 weeks thereafter. Maternal separation impaired developmental weight gain (P < 0.05), depressed NK cytotoxicity (P < 0.05), and increased tumor colonization in the presence of chronic restraint stress in adulthood (P < 0.00 l). These findings occurred independently of circulating plasma corticosterone as only adult stress exposure potentiated corticosterone responses (P < 0.05). Our findings indicate that maternal separation and chronic stress can impair NK cytotoxicity and hence tumor immunity, but these effects are not directly mediated by perturbations in HPA axis function.     

Influence of arm positions on EMG-reaction time of the biceps brachii for elbow flexion and forearm supination

The influence of starting positions of the arm on EMG-RTs of the biceps brachii muscle for elbow flexion and forearm supination was examined using 16 normal subjects. Two angles of the elbow joint, 45 degrees and 110 degrees flexion, and two positions of the forearm, 45 degrees supination and 90 degrees pronation, were used as the factorial combinations of all four. The EMG-RT for elbow flexion decreased in the order of 110 degrees Pronation greater than 45 degrees Pronation = 110 degrees Supination greater than 45 degrees Supination, and that for forearm supination decreased in the order of 45 degrees Supination greater than 45 degrees Pronation = 110 degrees Supination greater than 110 degrees Pronation. These results were kinesiologically interpreted that variations of EMG-RTs were based on the change in the number of synergic muscles participating in an intended movement and the muscle length of the prime mover at the start of the movement.     

Sequence of preparatory set for response movement

Electromyographic reaction times (EMG-RTs) of the right biceps brachii muscle were examined for two movement patterns, elbow flexion and forearm supination, in 8 healthy male subjects under simple and complex RT conditions with varied preparatory intervals (PIs): 0, 200, 400, 600, and 800 msec. In the simple RT condition, the subject was informed of the movement patterns to be performed prior to beginning the trials. In the complex RT condition the subject had to choose one of the two movement patterns at the time of the presentation of a warning signal. The results indicated that: (1) compared with the simple RT condition a delay of about 100 msec. in over-all mean EMG-RT was observed at PI = 0 msec. in the complex RT condition; (2) the difference of over-all mean EMG-RT between the two RT conditions disappeared when PI = 400 msec.; and (3) the difference in EMG-RTs between flexion and supination in the complex RT condition became the same as that in the simple RT condition when PI = 700 msec. It is assumed that the preparatory set for response movements is organized in an order, resulting in the differentiation of RT.     

Disturbances of rhythm formation in patients with Parkinson's disease: part II. a forced oscillation model

The origin of the characteristic disturbances of rhythm formation in patients with Parkinson's disease (the hastening phenomenon) was discussed, using a second-order system of the periodic response. The input signal was regarded as a pulse series of a Dirac function. The output process of the system had maximal errors of response at input frequencies of f = omega0/n (n = 1, 2, . . .), where omega0 was the intrinsic frequency of the system. Damping coefficient epsilon represented a function of an inhibitor against these maximal errors and the errors diverged to infinity when epsilon = 0. The solution of this forced oscillation system indicated that the intrinsic oscillation of the system has a possibility to be excited at these critical frequencies f = omega/n. Inferred from data on the tapping test, the frequency of an intrinsic oscillation was 5 Hz in the central nervous system, then the critical frequencies were predicted 5/n = 5, 2.5, . . . Hz. On the tapping test the errors of response become maximum around 2.5 and 5 Hz (taps per second), and their peak heights increased from the minimum in well trained normal subjects to the maximum in patients. An inhibitory mechanism against the maximal error would function well, i.e. epsilon greater than 0, in normal subjects but so insufficiently (epsilon leads to 0) in patients that the excited intrinsic oscillation would control their response directly. Thus some patients could no longer maintain a synchronous tapping response at 2.5 Hz or 5 Hz and showed a hastened tapping of 5 6 Hz independent of the signal frequency.     

Cross-cultural Differences in Self-reported Decision-making Style and Confidence

The Melbourne Decision Making Questionnaire (Mann, Burnett, Radford, & Ford, 1997) measures self-reported decision-making coping patterns. The questionnaire was administered to samples of University students in the US (N = 475), Australia (N = 262), New Zealand (N = 260), Japan (N = 359), Hong Kong (N = 281), and Taiwan (N = 414). As predicted, students from the three Western, individualistic cultures (US, Australia, and New Zealand) were more confident of their decision-making ability than students from the three East Asian, group-oriented cultures (Japan, Hong Kong, Taiwan). No cross-cultural differences were found in scores on decision vigilance (a careful decision-making style). However, compared with Western students, the Asian students tended to score higher on buck-passing and procrastination (avoidant styles of decision making) as well as hypervigilance (a panicky style of decision making). Japanese students scored lowest on decision self-esteem and highest on procrastination and hypervigilance. It was argued that the conflict model and its attendant coping patterns is relevant for describing and comparing decision making in both Western and Asian cultures.     

Overdistribution in source memory

Semantic false memories are confounded with a second type of error, overdistribution, in which items are attributed to contradictory episodic states. Overdistribution errors have proved to be more common than false memories when the 2 are disentangled. We investigated whether overdistribution is prevalent in another classic false memory paradigm: source monitoring. It is. Conventional false memory responses (source misattributions) were predominantly overdistribution errors, but unlike semantic false memory, overdistribution also accounted for more than half of true memory responses (correct source attributions). Experimental control of overdistribution was achieved via a series of manipulations that affected either recollection of contextual details or item memory (concreteness, frequency, list order, number of presentation contexts, and individual differences in verbatim memory). A theoretical model was used to analyze the data (conjoint process dissociation) that predicts that (a) overdistribution is directly proportional to item memory but inversely proportional to recollection and (b) item memory is not a necessary precondition for recollection of contextual details. The results were consistent with both predictions.     

Microstructure and mechanical properties of Mg–8Al alloy fabricated by room-temperature multi-directional forging

As-extruded Mg–Al alloy was multi-directionally forged (MDFed) at room temperature to cumulative strain of ΣΔ??=?2.0 at maximum by employing a pass strain of Δ??=?0.1. The coarse initial grains were subdivided gradually to ultra-fine ones by mechanical twinning. The MDFed Mg alloy showed superior mechanical properties of 530?MPa yield and 650?MPa ultimate tensile strengths with ductility of 9%. The relatively large ductility was induced by grain orientation randomization due to multiple twinning and the small pass strains which suppressed the sharp basal-texture evolution.     

Electron spin resonance of hydrogenated amorphous silicon-carbon alloy films prepared by magnetron sputtering

Abstract

New electron spin resonance (ESR) lines with g¹ = 2·0017 and g₂ and g₃ = 2·0006 have been found in the ESR spectra of as-deposited a-Si_1–x C_x:H films prepared by magnetron sputtering of silicon in the gas mixtures of methane and argon. Similarities between the observed spectra and those for the E′ centre in glassy SiO₂ are discussed.     

Changes in Families’ Caregiving Experiences through Involvement as Participants then Facilitators in a Family Peer‐Education Program for Mental Disorders in Japan

A family peer‐education program for mental disorders was developed in Japan, similar to existing programs in the United States and Hong Kong. Families that serve as facilitators in such programs may enhance their caregiving processes and, thereby, their well‐being. This study's aim was to describe how families’ caregiving experiences change, beginning with the onset of a family member's mental illness, through their involvement in a family group or peer‐education program as participants then facilitators. Thus, this study was conducted in a family peer‐education program for mental disorders in Japan. Group interviews were conducted with 27 facilitators from seven program sites about their experiences before, during, and after becoming facilitators. Interview data were coded and categorized into five stages of caregiving processes: (1) withdrawing and suppressing negative experiences with difficulty and regret; (2) finding comfort through being listened to about negative experiences; (3) supporting participants’ sharing as facilitators; (4) understanding and affirming oneself through repeated sharing of experiences; and (5) finding value and social roles in one's experiences. The third, fourth, and fifth stages were experienced by the facilitators. The value that the facilitators placed on their caregiving experiences changed from negative to positive, which participants regarded as helpful and supportive. We conclude that serving as facilitators may improve families’ caregiving processes.