Features of Psychomotor Responses and Interhemispheric Relationships at Various Stages of Adaptation to a New Time Zone

Motor response precision (MRP) as dependent on the functional asymmetry of the hands was analyzed before and after transmeridian flights across seven time zones. The MRPs of the two hands were relatively balanced under normal conditions and asymmetrical under conditions of immediate or late adaptation to a new time zone. The functions of the right hemisphere were affected mainly by acute desynchronosis, and those of the left hemisphere, by latent desynchronosis. As the functional indices and circadian biorhythms normalized, the initial domination of the left hemisphere strengthened.     

Age-related Features of Circadian Dynamics of Velocity of Reaction to Visual Stimuli in 8- to 14-Year-Old Boys

Studying individual circadian psychophysiological rhythms in children and adolescents, the authors showed that different rhythmological indices, such as fluctuation amplitude, mean level, and rhythm phase, change with age in different manners. Changes in one or more of these indices reflect a complex stagewise process of the formation of functions in human ontogeny. Additionally, a mismatch between individual and social (school load) rhythms may result in desynchronosis.     

Measuring-off of Time Intervals: Correlations Between Peculiarities of Their Estimation and Parameters of EEG Phenomena, and Influence of the Subjects' Personality Features

In 76 healthy persons (right-handed men and women), we recorded background EEG and event-related potentials from the C3 and C4 sites; tests were performed within the framework of an experimental situation requiring internal measuring-off of the time intervals. To limit the interval, the tested person had to push a button; he/she did not know the precise value of the interval, which was preset by the experimenter, and was informed only of the lower and upper limits of this interval, 17 to 23 sec. The person obtained information about the coincidence/noncoincidence of the measured-off and preset intervals via visual feedback; the respective signal was presented 2 sec after measuring-off had been completed. In the case where the intervals coincided with each other, the person should confirm this by pushing the button next time (confirming push). We characterized the parameters of the measured-off time interval by the following indices: (i) measuring-off efficacy (accuracy of fitting the preset interval), (ii) estimation tendency (measured-off interval/preset standard interval ratio), and (iii) coefficient of variation (CV) of the measured-off interval. Features of the subject's personality were estimated using Eysenck's (PEN) and Cattell's (16PF) questionnaires. We found correlations of the powers of the background EEG rhythms (beta1, beta2, and alpha/theta ratio) and characteristics of the measured-off time interval. In addition, we observed significant positive correlations between the estimation tendency and extraversion index and between CV of the interval and urge toward domination and protension indices. Negative correlations were observed between the measuring-off efficacy and protension (suspiciousness), between the estimation tendency and anxiety, and between the CV of the interval and age of the subjects. We support the conclusion that correlations between the patterns of EEG potentials, peculiarities of measuring-off of the time interval, and psychological features of the personality are to a noticeable extent mediated by the individual specificity of the neurodynamics.     

On the Problem of Cooperation of the Reaction of Hands: I. Cooperation of Hand Reaction to Sound and Light Stimuli in Healthy Subjects

Coordinated reaction of hands was analyzed during examination of healthy subjects and patients with focal lesions of the central nervous system in order to find the morphological structures responsible for such cooperation. Results of investigation of coordinated hand reaction in healthy subjects to sound and light stimuli with a warning signal are presented. The degree of cooperation was estimated by the correlation coefficient between the values of the reaction time of the right and left hands under conditions of their simultaneous response. In healthy subjects, there exists a strong positive correlation, whose variability in repeated examinations is determined by constitutional features of the subject.     

Dual Task Performance in Normal Aging: A Comparison of Choice Reaction Time Tasks

This study examined dual task performance in 28 younger (18–30 years) and 28 older (>60 years) adults using two sets of choice reaction time (RT) tasks paired with digit tasks. Set one paired simple choice RT with digit forward; set two paired complex choice RT with digit backward. Each task within each set had easy and hard conditions. For the simple choice RT, participants viewed single letters and pressed a specified keyboard key if the letter was X or Z or a different key for other letters (easy). For the hard condition, there were 4 target letters (X, Z, O, Y). Digit forward consisted of 4 (easy) or 5 (hard) digits. For the complex choice RT, participants viewed 4×4 matrices of Xs and Os, and indicated whether four Xs (easy) or four Xs or four Os (hard) appeared in a row. Digit backward consisted of 3 (easy) or 4 (hard) digits. Within each set, participants performed every possible combination of tasks. We found that in the simple choice RT tasks older adults were significantly slower than, but as accurate as younger adults. In the complex choice RT tasks, older adults were significantly less accurate, but as fast as younger adults. For both age groups and both dual task sets, RT decreased and error rates increased with greater task difficulty. Older adults had greater dual task costs for error rates in the simple choice RT, whereas in the complex choice RT, it was the younger group that had greater dual task costs. Findings suggest that younger and older adults may adopt differential behavioral strategies depending on complexity and difficulty of dual tasks.     

Building a Hybrid Physical-Statistical Classifier for Predicting the Effect of Variants Related to Protein-Drug Interactions

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From Single Cells to Tissues: Interactions between the Matrix and Human Breast Cells in Real Time

Background

Mammary gland morphogenesis involves ductal elongation, branching, and budding. All of these processes are mediated by stroma - epithelium interactions. Biomechanical factors, such as matrix stiffness, have been established as important factors in these interactions. For example, epithelial cells fail to form normal acinar structures in vitro in 3D gels that exceed the stiffness of a normal mammary gland. Additionally, heterogeneity in the spatial distribution of acini and ducts within individual collagen gels suggests that local organization of the matrix may guide morphogenesis. Here, we quantified the effects of both bulk material stiffness and local collagen fiber arrangement on epithelial morphogenesis.

Results

The formation of ducts and acini from single cells and the reorganization of the collagen fiber network were quantified using time-lapse confocal microscopy. MCF10A cells organized the surrounding collagen fibers during the first twelve hours after seeding. Collagen fiber density and alignment relative to the epithelial surface significantly increased within the first twelve hours and were a major influence in the shaping of the mammary epithelium. The addition of Matrigel to the collagen fiber network impaired cell-mediated reorganization of the matrix and increased the probability of spheroidal acini rather than branching ducts. The mechanical anisotropy created by regions of highly aligned collagen fibers facilitated elongation and branching, which was significantly correlated with fiber organization. In contrast, changes in bulk stiffness were not a strong predictor of this epithelial morphology.

Conclusions

Localized regions of collagen fiber alignment are required for ductal elongation and branching suggesting the importance of local mechanical anisotropy in mammary epithelial morphogenesis. Similar principles may govern the morphology of branching and budding in other tissues and organs.     

Wavelet-synchrony of Brain Evoked Responses during Listening to Naturalistic Stimuli in the Prognosis of Consciousness Recovery (Study 1: Wavelet-synchrony during Listening to Instrumental Music)

The features and prognostic value of wavelet-synchrony of evoked responses during the listening to realistic stimuli (music) were revealed in the study. Musical passages were selected according the patients’ preferences by their relations consultation. Wavelet-connections were calculated for each melody in the range from 0 to 1000 ms from stimuli. Total 22 examinees in 12 patients being in unconsciousness state were carried out. Resting state values of wavelet-connectivity were poorer in vegetative patients in comparison to healthy subjects regardless of consciousness recovery degree in future while wavelet-connections in mutism were higher in comparison to healthy subjects. Absolute value of wavelet-synchrony was lower than in norm. In patients with compete consciousness recovery in the future the maximal values of wavelet-synchrony were revealed in the temporal-occipital area while in patients who in the future have been revealed in the lesser degree the maximal values of wavelet-synchrony are shown in frontal-central areas. In chronic unconsciousness patients during the listening to instrumental music the maximal wavelet-connections values were determined in the right frontal area.     

Reaction of the muscles to disturbance during single-joint rhythmic movement

The muscle force action at the human elbow joint was studied during disturbed and non-disturbed horizontal rhythmic movement of forearm. It was shown that at the initial phase of unshocked perturbation++ the muscles efficiently resist the loading because its viscoelastic properties are quickly changed. Then the influence of the changes is almost vanished, apparently, with participation of nervous regulation.     

Specific Features of Neutrophil Response to Chorionic Gonadotropin Related to Sex and the Phase of the Menstrual Cycle

The effect of physiological doses of the main reproductive hormone chorionic gonadotropin (CG) on the functional activity of human neutrophils was studied. The hormone effectively modifies phagocytosis, respiratory burst, and the production of nitrogen oxide by cells. The effects of CG depend on sex and the phase of the menstrual cycle.     

Modulation of Inhibitory Synaptic Transmission in the Cat Motor Cortex Related to Realization of an Operant Reflex Evoked by a Complex of Stimuli

In non-anesthetized cats, we examined the effects of iontophoretic microinjections of GABA, a blocker of GABAergic synaptic transmission, and modulators of noradrenergic transmission on impulse activity (IA) generated by motor cortex neurons in the course of realization of an operant motor reflex to the action of a complex of stimuli (warning and imperative ones). We tried to elucidate the role of different membrane receptors in modulation of spiking of cortical neurons. Microiontophoretic applications of GABA and noradrenaline resulted in decreases in the frequency of background IA of cortical neurons and suppression of their reactions related to realization of the operant reflex. The use of selective adrenoactive substances showed that applications of an α1 agonist, Mezaton, suppressed background spiking and impulsation generated within an interspike interval and in the course of the movement. An α2 blocker, yohimbine, exerted an opposite effect; the neuronal IA was intensified within the background period and other examined time intervals. There are reasons to believe that noradrenergic modulation of IA of cortical neurons is realized via direct effects on pyramidal neurons and also indirectly, through changes in the activity of inhibitory cortical interneurons.     

Cross-Species Comparison of Genes Related to Nutrient Sensing Mechanisms Expressed along the Intestine

Introduction

Intestinal chemosensory receptors and transporters are able to detect food-derived molecules and are involved in the modulation of gut hormone release. Gut hormones play an important role in the regulation of food intake and the control of gastrointestinal functioning. This mechanism is often referred to as “nutrient sensing”. Knowledge of the distribution of chemosensors along the intestinal tract is important to gain insight in nutrient detection and sensing, both pivotal processes for the regulation of food intake. However, most knowledge is derived from rodents, whereas studies in man and pig are limited, and cross-species comparisons are lacking.

Aim

To characterize and compare intestinal expression patterns of genes related to nutrient sensing in mice, pigs and humans.

Methods

Mucosal biopsy samples taken at six locations in human intestine (n = 40) were analyzed by qPCR. Intestinal scrapings from 14 locations in pigs (n = 6) and from 10 locations in mice (n = 4) were analyzed by qPCR and microarray, respectively. The gene expression of glucagon, cholecystokinin, peptide YY, glucagon-like peptide-1 receptor, taste receptor T1R3, sodium/glucose cotransporter, peptide transporter-1, GPR120, taste receptor T1R1, GPR119 and GPR93 was investigated. Partial least squares (PLS) modeling was used to compare the intestinal expression pattern between the three species.

Results and conclusion

The studied genes were found to display specific expression patterns along the intestinal tract. PLS analysis showed a high similarity between human, pig and mouse in the expression of genes related to nutrient sensing in the distal ileum, and between human and pig in the colon. The gene expression pattern was most deviating between the species in the proximal intestine. Our results give new insights in interspecies similarities and provide new leads for translational research and models aiming to modulate food intake processes in man.     

Reaction Time and Mortality from the Major Causes of Death: The NHANES-III Study

Objective

Studies examining the relation of information processing speed, as measured by reaction time, with mortality are scarce. We explored these associations in a representative sample of the US population.

Methods

Participants were 5,134 adults (2,342 men) aged 20–59 years from the Third National Health and Nutrition Examination Survey (NHANES III, 1988–94).

Results

Adjusted for age, sex, and ethnic minority status, a 1 SD slower reaction time was associated with a raised risk of mortality from all-causes (HR = 1.25, 95% CI 1.12, 1.39) and cardiovascular disease (CVD) (HR = 1.36, 95% CI 1.17, 1.58). Having 1 SD more variable reaction time was also associated with greater risk of all-cause (HR = 1.36, 95% CI 1.19, 1.55) and CVD (HR = 1.50, 95% CI 1.33, 1.70) mortality. No associations were observed for cancer mortality. The magnitude of the relationships was comparable in size to established risk factors in this dataset, such as smoking.

Interpretation

Alongside better-established risk factors, reaction time is associated with increased risk of premature death and cardiovascular disease. It is a candidate risk factor for all-cause and cause-specific mortality.     

Induction of Pathogenesis-related Proteins in Barley during the Resistance Reaction to Mildew

Changes in the soluble protein pattern of leaves of eight lines of barley, carrying different resistance genes to mildew, were analysed by SDS-polyacrylamide gel electrophoresis and isoelectric focusing. Apparently new host proteins were induced by Erysiphe graminis f. sp. hordei in the incompatible reaction which were not present in the immune or susceptible response. These proteins are of low molecular weight, 13,500–27,500 d, and have either very low or very high isoelectric points. Thus, they resemble the pathogenesis-related proteins found in many dicotyledonous species.