The Effects of Volatile Anesthetics on Renal Sympathetic and Phrenic Nerve Activity during Acute Intermittent Hypoxia in Rats.

Coordinated activation of sympathetic and respiratory nervous systems is crucial in responses to noxious stimuli such as intermittent hypoxia. Acute intermittent hypoxia (AIH) is a valuable model for studying obstructive sleep apnea (OSA) pathophysiology, and stimulation of breathing during AIH is known to elicit long-term changes in respiratory and sympathetic functions. The aim of this study was to record the renal sympathetic nerve activity (RSNA) and phrenic nerve activity (PNA) during the AIH protocol in rats exposed to monoanesthesia with sevoflurane or isoflurane. Adult male Sprague-Dawley rats (n = 24; weight: 280-360 g) were selected and randomly divided into three groups: two experimental groups (sevoflurane group, n = 6; isoflurane group, n = 6) and a control group (urethane group, n = 12). The AIH protocol was identical in all studied groups and consisted in delivering five 3 min-long hypoxic episodes (fraction of inspired oxygen, FiO2 = 0.09), separated by 3 min recovery intervals at FiO2 = 0.5. Volatile anesthetics, isoflurane and sevoflurane, blunted the RSNA response to AIH in comparison to urethane anesthesia. Additionally, the PNA response to acute intermittent hypoxia was preserved, indicating that the respiratory system might be more robust than the sympathetic system response during exposure to acute intermittent hypoxia.

The COVID-19 lockdown promotes changes in sleep habits in the Croatian general population.

AIM: To investigate the effects of the coronavirus disease 2019 (COVID-19) lockdown on sleep habits in the Croatian general population. METHODS: In this cross-sectional study, 1173 respondents from the general population (809 women) completed a self-report online questionnaire that gathered demographic data and data on sleep habits and mood changes before and during the COVID-19 lockdown. RESULTS: During the lockdown, bedtime (from 23:11±1:07 to 23:49±1:32 h, P<0.001) and waketime were delayed (from 6:51±1:09 to 7:49±1:40 h, P<0.001). Sleep latency increased from 10 (5-20) to 15 (10-30) minutes (P<0.001). Bedtime and waketime delays were more pronounced in women and respondents younger than 30. Compared with other age groups, respondents younger than 30 more frequently reported insomnia for the first time during the lockdown and had less frequent night-time awakenings (P<0.001), less common problems falling asleep (P<0.001), less frequently felt calm (P<0.001) and rested (P<0.001), but more frequently felt sadness (P<0.001) and fear (P=0.028). CONCLUSION: The effect of the lockdown on sleep needs to be better understood. Sleep hygiene education could serve a first-line lifestyle intervention for people in lockdown experiencing sleep disruption.

The effect of COVID-19 lockdown on lifestyle and mood in Croatian general population: a cross-sectional study.

AIM: To investigate the effect of the coronavirus 2019 (COVID-19) lockdown on lifestyle behaviors and mood changes in the Croatian general population. METHODS: During ten days of the COVID-19 lockdown in Croatia, 3027 respondents (70.3% female) from the general population completed an online, self-report questionnaire. Demographic data and data on lifestyle habits and mood changes before and during the COVID-19 lockdown were collected. RESULTS: A total of 95.64% of respondents reported to follow most or all restrictions, with female sex (P<0.001) and higher education level (P<0.001) being associated with higher restriction compliance. Women smoked an increased number of cigarettes (P<0.001). The proportion of respondents of both sexes who did not drink or drank 7 drinks per week or more increased (P<0.001). Women also reported lower frequency (P=0.001) and duration of physical exercise (P<0.001). In total, 30.7% of respondents gained weight, with female sex (OR, 2.726) and higher BMI (OR, 1.116; both P<0.001) being associated with an increased likelihood of gaining weight. Both men and women felt more frequently afraid (P<0.001), discouraged (P<0.001), and sad (P<0.001). CONCLUSION: Public health authorities should promote the adoption of healthy lifestyles in order to reduce long-term negative effects of the lockdown.

Characterization of dorsal root ganglion neurons cultured on silicon micro-pillar substrates.

Our study focuses on characterization of dorsal root ganglion (DRG) neurons cultured on silicon micro-pillar substrates (MPS) with the ultimate goal of designing micro-electrode arrays (MEAs) for successful electrophysiological recordings of DRG neurons. Adult and neonatal DRG neurons were cultured on MPS and glass coverslips for 7 days in vitro. DRG neuronal distribution and morphometric analysis, including neurite alignment and length, was performed on MPS areas with different pillar width and spacing. We showed that MPS provide an environment for growth of adult and neonatal DRG neurons as permissive as control glass surfaces. Neonatal DRG neurons were present on MPS areas with narrow pillar spacing, while adult neurons preferred wider pillar spacing. Compared to the control glass surfaces the neonatal and adult DRG neurons in regions with narrow pillar spacing range developed a smaller number of longer neurites. In the same area, neurites were preferentially oriented along three directional axes at 30°, 90° and 150°. MPS architecture influenced growth directionality of all main DRG neuronal subtypes. We can conclude that specific micro-pillar substrate topography affects the morphology of DRG neurons. This knowledge can enable development of MEAs with precisely defined physical features for various neuroscience applications.