Stress, geomagnetic disturbance, infradian and circadian sampling for circulating corticosterone and models of human depression?

The Influence of Changes in Magnetic Variations and Light-Dark Cycle on Life-History Traits of Daphnia magna

Day-night cycle is the main zeitgeber (time giver) for biological circadian rhythms. Recently, it was suggested that natural diurnal geomagnetic variation may also be utilized by organisms for the synchronization of these rhythms. In this study, life-history traits in Daphnia magna were evaluated after short-term and multigenerational exposure to 16 h day/8 h night cycle, 32 h day/16 h night cycle, diurnal geomagnetic variation of 24 h, simulated magnetic variation of 48 h, and combinations of these conditions. With short-term exposure, the lighting mode substantially influenced the brood to brood period and the lifespan in daphnids. The brood to brood period, brood size, and body length of crustaceans similarly depended on the lighting mode during the multigenerational exposure. At the same time, an interaction of lighting mode and magnetic variations affected to a lesser extent brood to brood period, brood size, and newborn's body length. The influence of simulated diurnal variation on life-history traits in daphnids appeared distinctly as effects of synchronization between periods of lighting mode and magnetic variations during the multigenerational exposure. Newborn's body length significantly depended on the lighting regime when the periods of both studied zeitgebers were unsynchronized, or on the interaction of light regime with magnetic variations when the periods were synchronized. These results confirm the hypothesis that diurnal geomagnetic variation is an additional zeitgeber for biological circadian rhythms. Possible mechanisms for these observed effects are discussed. Bioelectromagnetics. © 2020 Bioelectromagnetics Society.

Impairment in behavioral sedation in rats during periods of elevated global geomagnetic activity

The influence of the geomagnetic environment on the human organism and other biological entities has been a topic of intense scientific investigation. A large and growing body of evidence has linked elevated geomagnetic activity with effects on an array of neurological, immunological, cardiovascular, and psychological outcomes. For example, elevations in the rates of epileptic seizures, suicides, aggressive behavior, sleep disturbances, and sudden unexpected death from cardiac pathologies have been reported to occur more frequently on days associated with increased geomagnetic activity. Additional evidence also suggests that geomagnetic conditions might have an impact on the biological actions of specific drugs classes that have important implications for pain management, sedation, and seizure control. The present study set out to determine if periods of enhanced geomagnetic activity could influence the induction of behavioral sedation by pentobarbital in rodents undergoing a routine surgical procedure. The surgical records of 250 subjects were retrospectively analyzed, and the occurrence of complete behavioral sedation (e.g., loss of righting reflex, lack of nociceptive response to tail pinch, absence of corneal and conjunctive reflexes) was noted. We found a significant correlation between periods of increased geomagnetic activity and the number of non-responsive surgical patients (i.e., patients still demonstrating behavioral responsiveness after treatment with pentobarbital). These findings provide evidence for the first time that the potential efficacy of some surgical anesthetic compounds might be reduced on days associated with increased geomagnetic activity. Potential mechanisms are presented, and the broad implications of these findings to phenomena such as surgical awareness are discussed.

Cross-sectional survey on self-reported health of ambulance personnel

Background

The high job stress among ambulance personnel is a widely known phenomenon. Purpose: to asses the self reported health status of ambulance workers.

Methods

An anonym self-fill-in questionnaire applying SF-36 was used among workers from the northern and western regions of Hungarian National Ambulance Service.

Results

Based on the dimensions of the SF-36 questionnaire the respondents considered their “Physical Functioning” the best, while “Vitality” was regarded the worst. The more time an employee have been worked at the HNAS the worse his health was in the first four dimensions like, “Physical Functioning”, “Role-Physical”, “Bodily Pain”, “General Health”: p < 0.001. Those working in secondary part-time jobs considered their health in all dimensions worse. The respondents who did some kind of sports hold their health in all dimensions better (p < 0.001). The workers with higher BMI regarded their health status worse, in four dimensions: “Physical Functioning”: p = 0.001; “Role-Physical”: p = 0.013; “General Health”: p < 0.001; “Role-Emotional”: p = 0.05.

Conclusions

The workers health status proved to be insufficient according to the subjective perception and measurable parameters. According to the subjective perception of health and measurable parameters of health status of workers proved to be insufficient. Poor physical health can lead indirectly to psychological problems, which may lower the quality of the work and can lead to high turn-over.

[Utilization of physiotherapy services for traumatic disorders of the lower extremity in ambulatory care]

INTRODUCTION

Limited information is available on physiotherapy treatment of lower extremity injuries.

AIM

The purpose of this study included analysis of the utilization of outpatient physiotherapy services in case of injuries of the lower extremity.

METHOD

Data derived from the database of the National Health Insurance Fund Administration, Hungary. The number of cases undergoing physiotherapy activities after lower extremity injuries were determined.

RESULTS

In 2009 the average number of cases undergoing physiotherapy activities following lower extremity injuries per 10,000 persons were the following: "hip and thigh injuries" 249.75 male cases and 443.7 female cases; "knee and leg injuries" 927.64 male cases and 668.25 female cases, and "ankle and foot injuries" 307.58 male cases and 245.75 female cases.

CONCLUSIONS

According to this study, the number of physiotherapy activities for patients with injuries of the lower extremity showed significant differences between genders.

Earthquake distresses reproductive function but not fetal development in rats

BACKGROUND

It is well known that earthquake severely threatens life-safety and physical damage. However, the empirical literature on the effects of nature disasters such as earthquake on the reproductive outcomes is limited.

METHODS

On May 12th, 2008, a massive 8.0 magnitude earthquake occurred in Wenchuan, a city 92 km away from our animal facility [National Chengdu Center for Safety Evaluation of Drugs (NCCSED)]. To investigate whether this tremendous earthquake exerted adverse effects on the reproductive and developmental functions in Sprague-Dawley rats, we collected some relevant data from reproductive toxicity studies around the earthquake, and compared them with the background data, which were gathered before and after the earthquake. Copulation ratio, gestation ratio, and fertility of female rats, as well as uterine and fetal morphology, were examined.

RESULTS

Our data demonstrated that the Wenchuan earthquake significantly decreased the copulation and gestation ratio, although it did not exhibit obvious side effects on some other reproductive and developmental parameters.

Behavioral change related to Wenchuan devastating earthquake in mice

It has been suggested that some animals are much more capable of perceiving certain kinds of geophysical stimuli which may precede earthquakes than humans, but the anecdotal phenomena or stories about unusual animal behaviors prior to an earthquake should be interpreted with objective data. During the Wenchuan magnitude 8.0 earthquake that happened in Wenchuan county (31.0 degrees north latitude, 103.4 degrees east longitude) of Sichuan province, China, on May 12, 2008, eight mice were monitored for locomotor activity and circadian rhythm in constant darkness with temperature 22-24 degrees C and humidity 55-65% for 38 days. The ongoing monitoring of locomotor activity of mice in our laboratory made it possible to design a posteriori study investigating whether the earthquake was associated with any change in animal behavior. Based on analyzing the recorded data with single cosinor, we found that the locomotor activity dramatically decreased in six of these eight mice on day 3 before the earthquake, and the circadian rhythm of their locomotor activity was no longer detected. The behavioral change lasted for 6 days before the locomotor activity returned to its original state. Analyses of concurrent geomagnetic data showed a higher total intensity during the span when the circadian rhythm in locomotor activity weakened. These results indicated that the behaviors, including circadian rhythm and activity, in these mice indeed changed prior to the earthquake, and the behavioral change might be associated with a change of geomagnetic intensity.