Relationship between Field Strength and Abnormal Development in Chick Embryos Exposed to 50 Hz Magnetic Fields

Summary

Chick embryos were exposed to sinusoidally oscillating 50 Hz magnetic fields during their first 2 days of development. In the first series of experiments magnetic field strengths of 0·1, 0·3, 1 and 10 A/m were used. The percentage of abnormal embryos (%AE) was 16 per cent in the sham-exposed control group. %AE was increased at 1 A/m (29 per cent) and 10 A/m (32 per cent), but not at 0·1 A/m (16 per cent) or 0·3 A/m (14 per cent). In the second series of experiments field strengths of 0·4, 0·6, 0·9 and 1·35 A/m were used. %AE was 17 per cent in the control group, 10 per cent at 0·4 A/m, 19 per cent at 0·6 A/m, 17 per cent at 0·9 A/m and 36 per cent at 1·35 A/m. Only the 1·35 A/m group was significantly different from the controls. The results of this study suggest that exposure of chick embryos to a 50 Hz magnetic field causes abnormal development, and that no abnormalities are induced below a threshold between 0·9 and 1 A/m.     

The Psychiatric Burden on Medical Students in New York City Entering Clinical Clerkships During the COVID-19 Pandemic

For medical students first entering the clinical space in July 2020, the unique challenges related to the coronavirus pandemic threatened to amplify the psychological distress associated with clerkship rotations. This study aimed to characterize the mental health of third-year medical students starting clinical clerkships in the midst of a pandemic by assessing symptoms of major depressive disorder (MDD), generalized anxiety disorder (GAD), and posttraumatic stress disorder (PTSD) as well as risk, coping, and protective factors associated with psychological outcomes. Of 147 third-year medical students at the Icahn School of Medicine at Mount Sinai in New York City, 110 (75%) participated in this prospective survey-based study with 108 included in the final analysis. 43 (39.8%) respondents screened positive for symptoms of either MDD, GAD, or PTSD. Multiple regression analyses revealed that greater overall symptom severity was associated with more avoidant coping, more traumatic events witnessed, poorer student and leisure functioning, lower trait emotional stability, and lower social support. Worries related to COVID-19 did not significantly influence outcome variables. To better understand the role of the pandemic on psychological outcomes in third-year medical students, additional research should focus on the trajectory of these outcomes over the year during the coronavirus pandemic.

     

The effect of breathing frequency on deposition of drug aerosol using an inhalation-synchronized dosimeter in healthy adults.

The deposition of inhaled drug aerosol between the tongue, the upper and lower respiratory tract, the lungs and the gastrointestinal tract (GI tract) in 11 healthy adults was studied by using a nebulizer with an inhalation-synchronized dosimeter. The effect of breathing frequency on deposition was studied using radioaerosol (mixture of salbutamol and technetium bound to diethylenetriamine pentacetate, [99mTc]DTPA) and a gamma-camera. In healthy subjects who were breathing at their own frequency (16 +/- 5 breaths min-1, mean +/- SD), the proportion of inhaled aerosol deposited in the lungs was 48 +/- 14 (mean percentage +/- SD). The proportion deposited in the upper airway tract and the GI tract was 19 +/- 13 and 25 +/- 9 respectively, and the remainder was deposited on the tongue (6 +/- 4) and in the lower airway tract (3 +/- 2). Guided, slower breathing frequency (11 +/- 5 breaths min-1) changed the deposition remarkably. The proportion of the pulmonary deposition of the inhaled dose increased significantly (P < 0.004) to 60 +/- 17, and the proportion of the upper airway tract deposition decreased significantly (P < 0.005) by half of the initial deposition. We conclude that a slow controlled breathing frequency is an important factor if we want to increase the drug deposition in the lungs. It is also essential in decreasing the variation in the deposition of the lungs.     

Impulse control disorders in Parkinson disease: A cross-sectional study in Morocco

Impulse control disorders (ICDs) in Parkinson's disease (PD) comprise a class of psycho-behavioral disorders often associated with dopamine agonist treatment. The aim of our study was to determine the prevalence of ICDs in a group of Moroccan PD patients and to bring forward some specific aspects in our population. One hundred twenty-five PD patients, without memory impairment and treated for at least six months, were studied. They were questioned about ICDs using the QUIP-RS, and simultaneously evaluated on the motor symptoms and their treatment. Our sample was then divided into two groups: ICDs (+) and ICDs (?) groups. ICDs were identified in 28% of patients: pathological gambling in 3.2%, compulsive sexual behavior in 7.2%, pathological buying in 9.6%, eating behavior disorder in 7.2%, punding-hobbyism in 11.1%. At least two ICDs were found in 14% of patients and dopamine dysregulation syndrome in 10.4%. We also noticed another kind of “ICDs-mimics” specific to our own social context such as “excessive charity” in 18.4%, or excessive reading of the Qur’an in 9.6%. These aspects were not included in the calculation of ICDs prevalence. The ICDs (+) group was younger than the ICDs (?) group (P = 0.042) and ICDs were more frequent in men (P = 0.031). Dopamine agonist equivalent daily dose (DAED) was significantly higher (P = 0.01) in the ICDs (+) group. There are no differences between classes of dopamine agonist used. Young age, male gender and DAED are risk factors for the occurrence of ICDs in Moroccan PD patients, as already described in the DOMINION cohort, but the prevalence found in our study was higher. We highlighted some specific ICDs-mimics in our Arab-Muslim population.     

The effect of breathing frequency on deposition of drug aerosol using an inhalation-synchronized dosimeter in healthy adults

The deposition of inhaled drug aerosol between the tongue, the upper and lower respiratory tract, the lungs and the gastrointestinal tract (GI tract) in 11 healthy adults was studied by using a nebulizer with an inhalation-synchronized dosimeter. The effect of breathing frequency on deposition was studied using radioaerosol (mixture of salbutamol and technetium bound to diethylenetriamine pentacetate, [^99mTc]DTPA) and a gamma-camera. In healthy subjects who were breathing at their own frequency (16 ± 5 breaths min^–1, mean ± SD), the proportion of inhaled aerosol deposited in the lungs was 48 ± 14 (mean percentage ± SD). The proportion deposited in the upper airway tract and the GI tract was 19 ± 13 and 25 ± 9 respectively, and the remainder was deposited on the tongue (6 ± 4) and in the lower airway tract (3 ± 2). Guided, slower breathing frequency (11 ± 5 breaths min^–1) changed the deposition remarkably. The proportion of the pulmonary deposition of the inhaled dose increased significantly (P<0·004) to 60 ± 17, and the proportion of the upper airway tract deposition decreased significantly (P<0·005) by half of the initial deposition. We conclude that a slow controlled breathing frequency is an important factor if we want to increase the drug deposition in the lungs. It is also essential in decreasing the variation in the deposition of the lungs.     

Measurements of extremely low-frequency magnetic fields around video display terminals

The extremely low-frequency (ELF) magnetic field emissions of seven video display terminal (VDT) models were measured. A measuring coil with a linearized frequency response (50 Hz to 25 kHz) was used. The dominating ELF magnetic field around the terminals was the 50 or 60 Hz asymmetric triangular waveform from the vertical deflection coil of the cathode ray tube. At the distance of 50 cm, the magnetic field strength was still slightly higher than the background level in usual office rooms, but several orders of magnitude lower than the thresholds of known interaction mechanisms. Some recent experiments suggest that certain biological effects may occur at field strengths only a few times higher than those found at the position of VDT operators, but the significance of these effects to human health is not known.