Simulated space environmental factors of weightlessness, noise and low atmospheric pressure differentially affect the diurnal rhythm and the gut microbiome

The circadian clock extensively regulates physiology and behavior. In space, astronauts encounter many environmental factors that are dramatically different from those on Earth; however, the effects of these factors on circadian rhythms and the mechanisms remain largely unknown. The present study aimed to investigate the changes in the mouse diurnal rhythm and gut microbiome under simulated space capsule conditions, including microgravity, noise and low atmospheric pressure (LAP). Noise and LAP were loaded in the capsule while the conditions in the animal room remained constant. The mice in the capsule showed disturbed locomotor rhythms and faster adaptation to a 6-h phase advance. RNA sequencing of hypothalamus samples containing the suprachiasmatic nucleus (SCN) revealed that microgravity simulated by hind limb unloading (HU) and exposure to noise and LAP led to decreases in the quantities of differentially expressed genes (DEGs), including circadian clock genes. Changes in the rhythmicity of genes implicated in pathways of cardiovascular deconditioning and more concentrated phases were found under HU or noise and LAP. Furthermore, 16S rRNA sequencing revealed dysbiosis in the gut microbiome, and noise and LAP may repress the temporal discrepancy in the microbiome community structure induced by microgravity. Changes in diurnal oscillations were observed in a number of gut bacteria with critical physiological consequences on metabolism and immunodefense. We also found that the superimposition of noise and LAP may repress normal changes in global gene expression and adaptation in the gut microbiome. Our data demonstrate that in addition to microgravity, exposure to noise and LAP affect the robustness of circadian rhythms and the community structure of the gut microbiome, and these factors may interfere with each other in their adaptation to respective conditions. These findings are important for furthering our understanding of the alterations in circadian rhythms in the complex environment of space.

Atmospheric pressure predicts probability of departure for migratory songbirds

BACKGROUND

Weather can have both delayed and immediate impacts on animal populations, and species have evolved behavioral adaptions to respond to weather conditions. Weather has long been hypothesized to affect the timing and intensity of avian migration, and radar studies have demonstrated strong correlations between weather and broad-scale migration patterns. How weather affects individual decisions about the initiation of migratory flights, particularly at the beginning of migration, remains uncertain.

METHODS

Here, we combine automated radio telemetry data from four species of songbirds collected at five breeding and wintering sites in North America with hourly weather data from a global weather model. We use these data to determine how wind profit, atmospheric pressure, precipitation, and cloud cover affect probability of departure from breeding and wintering sites.

RESULTS

We found that the probability of departure was related to changes in atmospheric pressure, almost completely regardless of species, season, or location. Individuals were more likely to depart on nights when atmospheric pressure had been rising over the past 24 h, which is predictive of fair weather over the next several days. By contrast, wind profit, precipitation, and cloud cover were each only informative predictors of departure probability in a single species.

CONCLUSIONS

Our results suggest that individual birds actively use weather information to inform decision-making regarding the initiation of departure from the breeding and wintering grounds. We propose that birds likely choose which date to depart on migration in a hierarchical fashion with weather not influencing decision-making until after the departure window has already been narrowed down by other ultimate and proximate factors.

Multi-sensor geolocators unveil global and local movements in an Alpine-breeding long-distance migrant

BACKGROUND

To understand the ecology of long-distance migrant bird species, it is necessary to study their full annual cycle, including migratory routes and stopovers. This is especially important for species in high-elevation habitats that are particularly vulnerable to environmental change. Here, we investigated both local and global movements during all parts of the annual cycle in a small trans-Saharan migratory bird breeding at high elevation.

METHODS

Recently, multi-sensor geolocators have opened new research opportunities in small-sized migratory organisms. We tagged Northern Wheatears Oenanthe oenanthe from the central-European Alpine population with loggers recording atmospheric pressure and light intensity. We modelled migration routes and identified stopover and non-breeding sites by correlating the atmospheric pressure measured on the birds with global atmospheric pressure data. Furthermore, we compared barrier-crossing flights with other migratory flights and studied the movement behaviour throughout the annual cycle.

RESULTS

All eight tracked individuals crossed the Mediterranean Sea, using islands for short stops, and made longer stopovers in the Atlas highlands. Single non-breeding sites were used during the entire boreal winter and were all located in the same region of the Sahel. Spring migration was recorded for four individuals with similar or slightly different routes compared to autumn. Migratory flights were typically nocturnal and characterized by fluctuating altitudes, frequently reaching 2000 to 4000 m a.s.l, with a maximum of up to 5150 m. Barrier-crossing flights, i.e., over the sea and the Sahara, were longer, higher, and faster compared to flights above favourable stopover habitat. In addition, we detected two types of altitudinal movements at the breeding site. Unexpected regular diel uphill movements were undertaken from the breeding territories towards nearby roosting sites at cliffs, while regional scale movements took place in response to local meteorological conditions during the pre-breeding period.

CONCLUSION

Our data inform on both local and global scale movements, providing new insights into migratory behaviour and local movements in small songbirds. This calls for a wider use of multi-sensor loggers in songbird migration research, especially for investigating both local and global movements in the same individuals.

Correlating atmospheric pressure and temperature with Meniere attack

OBJECTIVE

This paper correlated the Meniere attack with meteorological parameters i.e. atmospheric pressure, temperature, relative humidity and rainfall, to investigate which parameters that trigger the Meniere attack.

METHODS

During the past three years, totally 283 (2015), 351 (2016) and 319 (2017) patients with Meniere's disease (MD) were encountered at a clinic of the university hospital, accounting for 13%, 17% and 16% incidence in relation to overall annual neurotological cases, respectively. The onset of Meniere attack was then correlated with meteorological parameters.

RESULTS

The mean seasonal incidence of Meniere attack in relation to overall seasonal neurotological cases in 2015-2017 were 14.8 ± 2.8% (spring), 17.5 ± 2.2% (summer), 16.0 ± 1.8 % (autumn) and 12.8 ± 2.0% (winter), indicating that summer season had a higher incidence of Meniere attacks than winter season. Onset of Meniere attacks correlated significantly with the atmospheric pressure (r = -0.4484, p = 0.0061) and temperature (r = 0.4736, p = 0.0035), and the atmospheric pressure was highly negatively correlated with the temperature (r = -0.9421, p < 0.0001). In contrast, no correlation was identified between the onset of Meniere attacks and relative humidity or rainfall. The atmospheric pressure in the same month with typhoon compared with that without typhoon revealed a median reduction of 13.1 hectopascal.

CONCLUSION

Atmospheric pressure and temperature are correlated with the onset of Meniere attack. Summer season has a higher incidence of Meniere attack than winter season, likely because low atmospheric pressure in summer may aggravate endolymphatic hydrops, especially when accompanied by typhoons in the northwest Pacific region.

Seasonal dynamics of myocardial infarctions in regions with different types of a climate: a meta-analysis

BACKGROUND

It is known that cardiovascular events (CVE) occur more often in winter than in summer. However, dependence of myocardial infarction (MI) risk of on various meteorological factors is still not fully understood. Also, the dependence of the seasonal dynamics of MI on gender and age has not yet been studied. The purpose of our meta-analysis is to reveal dependence of the circannual dynamics of MI hospitalizations on gender, age, and characteristics of a region's climate.

MAIN BODY

Using Review Manager 5.3, we performed a meta-analysis of 26 publications on the seasonal dynamics of MI. In our meta-analysis, the relative MI risk was higher in colder compared to warmer seasons. Old age insignificantly increased the seasonal MI risk; gender did not affect the seasonal dynamics of MI, but MI was more common in men than in women. The severity of the seasonal dynamics of MI risk depended on the climate of the region. In a climate with a small amplitude of circannual fluctuations in air temperature, atmospheric pressure, and partial oxygen density in the air, as well as in regions where air humidity is higher in winter than in summer, an increase in MI risk in winter compared to summer was significant. It was not significant in regions with opposite climatic tendencies.

CONCLUSIONS

Based on the results of our studies, it can be concluded that a decrease in air temperature increases in MI risk; in addition, hypoxia in the hot season can provoke CVE associated with ischemia.

Association between meteorological factors and elderly falls in injury surveillance from 2014 to 2018 in Guangzhou, China

Introduction

With rapid increase in the aging population, falls injuries have become an important public health problem. However, limited data have been reported on the associations between meteorological factors and falls injuries in the elderly. This study assessed the epidemiology of falls injuries and explored this association in the elderly in Guangzhou, China.

Methods

Data on elderly falls injury cases and meteorological variables from 2014 to 2018 in Guangzhou were collected from the Guangzhou Injury Monitoring System and Guangzhou Meteorological Bureau, respectively. The monthly average data on falls injuries and meteorological factors were applied to the data analysis. These correlations were conducted using Pearson correlation analysis. A multiple linear regression model was used to estimate the effects of meteorological factors on falls injuries in the elderly in Guangzhou, China.

Results

Accounting for 49.41% of causes of elderly injury were falls in the Guangzhou Injury Monitoring System from 2014 to 2018, which occupied first place for five consecutive years. The monthly number of elderly falls injury cases was lowest in April and highest in December, and had a positive correlation with monthly mean wind speed (r = 0.187, P < 0.01) and a negative correlation with monthly atmospheric pressure (r = -0.142, P < 0.05). A multiple linear regression model was constructed (F = 10.176, P < 0.01), which explained 23.7% of the variances (R ² = 0.237). Monthly mean wind speed (β = 76.85, P < 0.01) and monthly mean atmospheric pressure (β = -3.162, P < 0.01) were independent factors affecting monthly elderly falls injuries.

Conclusions

Falls are the primary cause of injury among elderly people in Guangzhou, China. Meteorological factors are related to falls injuries in the elderly population. Decreasing activity during high wind and low atmospheric pressure weather may help reduce the number of elderly falls injury cases.

Ambient temperature and atmospheric pressure at discharge as precipitating factors in immediate adverse events in patients treated for decompensated heart failure

To investigate the relationship of ambient temperature and atmospheric pressure (AP) at patient discharge after an episode of acute heart failure (AHF) with very early post-discharge adverse outcomes. We analyzed 14,656 patients discharged after an AHF episode from 26 hospitals in 16 Spanish cities. The primary outcome was the 7-day post-discharge combined adverse event (emergency department -ED- revisit or hospitalization due to AHF, or all-cause death), and secondary outcomes were these three adverse events considered individually. Associations (adjusted for patient and demographic conditions, and length of stay -LOS- during the AHF index episode) of temperature and AP with the primary and secondary outcomes were investigated. We used restricted cubic splines to model the continuous non-linear association of temperature and AP with each endpoint. Some sensitivity analyses were performed. Patients were discharged after a median LOS of 5 days (IQR = 1-10). The highest temperature at discharge ranged from - 2 to 41.6 °C, and AP was from 892 to 1037 hPa. The 7-day post-discharge combined event occurred in 1242 patients (8.4%), with percentages of 7-day ED-revisit, hospitalization and death of 7.8%, 5.1% and 0.9%, respectively. We found no association between the maximal temperature and AP on the day of discharge and the primary or secondary outcomes. Similarly, there were no significant associations when the analyses were restricted to hospitalized patients (median LOS = 7 days, IQR = 4-11) during the index event, or when lag-1, lag-2 or the mean of the 3 post-discharge days (instead of point estimation) of ambient temperature and AP were considered. Temperature and AP on the day of patient discharge are not independently associated with the risk of very early adverse events during the vulnerable post-discharge period in patients discharged after an AHF episode.

Associations between meteorological variation and rupture of intracranial aneurysm in Fujian, China: A 5-year multicenter study

OBJECTIVE

By exploring the exposure-response relationships between meteorological factors and rupture of intracranial aneurysm (IA) to reveal the influence of meteorological variation on IA rupture under the specific climate in Fujian, China.

METHOD

7515 cases of IA rupture from several municipal medical institutions in Fujian Province as well as local meteorological data during the same period were collected from 2013 to 2017. Poisson regression and Spearman correlation analysis were applied to explore the distribution characteristics of IA rupture and how it is associated with meteorological parameters. Poisson generalized additive model was established to further analyze the exposure-response relationships between meteorological factors and IA rupture, and its hysteresis effects.

RESULT

The IA rupture exhibited a negative correlation with temperature (r_s = -0.323, 95% CI: -0.539 ~ -0.068) and a positive correlation with atmospheric pressure (r_s = 0.397, 95% CI: 0.152-0.597) or pressure difference (r_s = 0.296, 95% CI: 0.038-0.517), 21.05 ℃ and 1000.14 hPa were the risk thresholds for the onset ascribed to variation in temperature and atmospheric pressure, respectively. Temperature and atmospheric pressure also exerted hysteresis effects on IA rupture. Cold will increase the rupture risk in the subsequent 1-3 days, and high pressure will raise the morbidity in the next 1-2 days. Besides, drastic variations in temperature and atmospheric pressure were also associated with the higher risk of IA rupture in the next 2 days and 1 day, respectively.

CONCLUSION

Temperature and atmospheric pressure have a negative and positive correlation with IA rupture in Fujian, China, respectively. Variation in temperature and atmospheric pressure exert different degrees of hysteresis effects on IA rupture.

Effect of meteorological factors and lunar phases on occurrence of psychogenic nonepileptic seizures

BACKGROUND

Psychogenicnonepilepticseizures (PNES) lack the abnormal electrographical discharges in electroencephalogram seen in epileptic seizures. The notion of the effects of meteorological factors and lunar phases onoccurrence of seizures in patients with PNES has been the subject of very few research studies and the available evidence in the literature is equivocal. In this study, we aimed to study the influence oflunarphases and meteorological factors on the frequency of PNES and its semiological categories.

METHODS

We retrospectively reviewed the medical records of patients discharged with a diagnosis of PNES from our epilepsy monitoring unit in a 3-year period. The 119 patients who met the inclusion criteria were categorized into hypermotor, hypomotor, or intact sensorium based on semiology of their seizures. The occurrence of PNES, in total and in each semiological category, was correlated with the daily average temperature, atmospheric pressure, and the 4 lunar phases.

RESULTS

There were 31.8% and 11.1% more-than-expected captured seizures when the average daily atmospheric pressure was lower or higher, respectively, of what is generally considered a comfortable atmospheric pressure. No consistent relation was found between the full moon phases and occurrence of PNES.

CONCLUSION

A significant association between atmospheric pressure and the occurrence of nonepileptic seizures was found, whereas no consistent increase in PNES was observed during the full moon phases. There is still an open debate about the effect of the lunar phases on human behavior and neurological disorders such as PNES.

Comparison of bacterial microleakage of three bioactive endodontic sealers in simulated underwater diving and aviation conditions

BACKGROUND

Bacterial microleakage is an important cause of apical periodontitis and endodontic treatment failure. This study aimed to assess the bacterial microleakage of nano-mineral trioxide aggregate (nano-MTA) as a sealer, Endoseal MTA, and GuttaFlow Bioseal sealers in atmospheric pressure, and simulated underwater diving and aviation conditions.

METHODS

In this in vitro, experimental study, 180 extracted single-rooted teeth were cleaned and shaped, and were then randomly divided into three groups for single-cone obturation using Endoseal MTA, GuttaFlow Bioseal, or nano-MTA as a sealer. Each group was then randomly divided into three subgroups, and subjected to ambient atmospheric pressure, 2 atm pressure (to simulate underwater diving), and 0.5 atm pressure (to simulate aviation) using a custom-made pressure chamber. The teeth then underwent microbial leakage test using Streptococcus mutans (S. mutans), and the percentage of samples showing microleakage was recorded for up to 1 month, and analyzed using the Chi-square test.

RESULTS

The three sealer groups were significantly different regarding bacterial microleakage (P < 0.05). The nano-MTA group showed significantly higher microleakage after 15 days than the other two groups (P = 0.006). The effect of pressure on bacterial microleakage was not significant in any sealer group (P > 0.05).

CONCLUSION

Within the limitations of this in vitro study, it may be concluded that single-cone obturation technique using nano-MTA as a sealer results in lower resistance to bacterial microleakage compared with the use of GuttaFlow Bioseal, and Endoseal MTA. Pressure changes in simulated underwater diving and aviation conditions had no significant effect on bacterial microleakage. Trial Registration Number This is not a human subject research.

Why Hydrocephalus Patients Suffer When the Weather Changes: A New Hypothesis

Hydrocephalus patients complain about symptoms related to weather changes, especially changes in atmospheric pressure (p_at). We aimed to determine which physical, physiological, and pathophysiological effects can explain this phenomenon. We hypothesized that intracranial pressure (ICP) is influenced by changes of intracranial blood volume caused by autoregulatory changes in arterial diameter as a reaction to changing levels of arterial CO₂ partial pressure (paCO₂) caused by changes in atmospheric pressure (p_at). To test this hypothesis, we investigated the influence of p_at on paCO₂, and then assessed the influence of paCO₂ on ICP by extrapolating data found in the literature. Using conservative assumptions, we found that a change of p_at of about 50 hPa will result in a change in ICP of above 1.65 mmHg, which could explain the symptoms patients reported.

The effect of nitrogen dioxide and atmospheric pressure on hospitalization risk for chronic obstructive pulmonary disease in Guangzhou, China

BACKGROUND

The relationship between air pollution and meteorological factors on diseases has become a research hotspot recently. Nevertheless, few studies have touched the inferences of nitrogen dioxide (NO₂) and atmospheric pressure (AP) on hospitalization risk for chronic obstructive pulmonary disease (COPD).

OBJECTIVES

To investigate the short-term impact of particulate air pollutants and meteorology factors on hospitalizations for COPD and quantify the corresponding risk burden of hospital admission.

METHODS

In our study, COPD cases were collected from Guangzhou Panyu Central Hospital (n = 11,979) from Dec of 2013 to Jun 2019. The 24-h average temperature, relative humidity (RH), wind speed (V), AP and other meteorological data were obtained from Guangzhou Meteorological Bureau. Air pollution data were collected from Guangzhou Air Monitoring Station. The influence of different NO₂ and AP values on COPD risk was quantified by a distributed lag nonlinear model (DLNM) combined with Poisson Regression and Time Series analysis.

RESULTS

We found that NO₂ had a non-linear relationship with the incidence of COPD, with an approximate "M" type, appearing at the peaks of 126 μg/m³ (RR = 1.32, 95%CI, 1.07 to 1.64) and 168 μg/m³ (RR = 1.21, 95%CI, 0.94 to 1.55), respectively. And the association between AP and COPD incidence exhibited an approximate J-shape with a peak occurring at 1035 hPa (RR = 1.16, 95% CI, 1.02 to 1.31).

CONCLUSIONS

The nonlinear relationship of NO₂ and AP on COPD admission risk in different periods of lag can be used to establish an early warning system for diseases and reduce the possible outbreaks and burdens of COPD in a sensitive population.

Effects of climatic factors on human parainfluenza 1, 2, and 3 infections in Cheonan, Republic of Korea

Studying relationships between meteorological conditions and respiratory virus infections may help interpret the causality of disease outbreaks and provide a better understanding of the seasonal distribution of viruses. Therefore, in this study, we analyzed the correlations between meteorological data and the trends of infection by human parainfluenza virus-1 (HPIV-1; also known as human respirovirus 1), human parainfluenza virus-2 (human orthorubulavirus 2), and human parainfluenza virus-3 (human respirovirus 3) using 9010 viral samples collected at Dankook University Hospital from January 1, 2012, to December 31, 2018. Infection frequency data were used to detect the seasonal patterns of HPIV-1, HPIV-2, and HPIV-3 infections, and these patterns were compared with local weather data over the same period. We performed descriptive statistical analysis, frequency analysis, t test, and binomial logistic regression analysis to examine the relationships of weather and particulate matter conditions with the incidence of HPIV-1, HPIV-2, and HPIV-3 infections. The highest average infection rate with one of these three viruses (88.17%) was found in children aged 1-9 years. Specifically, the infection rate of HPIV-1 was 91.9% in children aged 1-9 years, whereas that of HPIV-2 and HPIV-3 was 86.3%. HPIV infection exhibited a meaningful relationship with climatic factors, such as temperature, wind-chill temperature, and atmospheric pressure. Our results suggest that climate changes might affect the rate of infection by HPIV. These findings may help in predicting the effectiveness of preventive strategies of HPIV infection.

Do meteorological factors influence the occurrence of acute aortic dissection? A 10-year retrospective institutional study

OBJECTIVE

This study aimed to clarify the relationship between meteorological factors and the occurrence of aortic dissection.

METHODS

The study included 282 consecutive patients who were admitted to our institute with acute aortic dissection over a 10-year period. The local meteorological data over the same period were analyzed.

RESULTS

On the days with occurrences of acute aortic dissection, there were significant differences in the following factors: the minimum and maximum temperature (p < 0.0001), difference in the minimum and maximum temperature from the 10-year average, atmospheric pressure (p < 0.0001), and difference in atmospheric pressure between the day of occurrence and the previous day. Cut-off values were determined by ROC curve analysis. Univariate analyses identified the following factors as significant predictors of the occurrence of acute aortic dissection: minimum temperature < 4.0 °C (OR 2.42, p < 0.0001), maximum temperature < 15.1 °C (OR 2.23, p < 0.0001), atmospheric pressure > 1008.9 hPa (OR 1.75, p < 0.0001), difference between the minimum temperature and 10-year average < 0.3 °C, difference between the maximum temperature and 10-year average < 0.44 °C; and the difference in atmospheric pressure between the day of occurrence and the previous day > 0.4 hPa. However, the differences of the minimum and maximum temperatures from the 10-year average were the only factors that remained significant in the multivariate analysis. The minimum (R² = 0.3055) and maximum temperatures (R² = 0.4151) were weakly and moderately correlated, respectively, with the occurrence of acute aortic dissection.

CONCLUSION

Meteorological factors influenced the occurrence of acute aortic dissection. In particular, a minimum temperature of < 4 °C and maximum temperature difference from the 10-year average < 0.44 °C was identified as strong risk factors for the occurrence of acute aortic dissection.

Nanomechanical sampling of material for nanoscale mass spectrometry chemical analysis

The ability to spatially resolve the chemical distribution of compounds on a surface is important in many applications ranging from biological to material science. To this extent, we have recently introduced a hybrid atomic force microscopy (AFM)-mass spectrometry (MS) system for direct thermal desorption and pyrolysis of material with nanoscale chemical resolution. However, spatially resolved direct surface heating using local thermal desorption becomes challenging on material surfaces with low melting points, because the material will undergo a melting phase transition due to heat dissipation prior to onset of thermal desorption. Therefore, we developed an approach using mechanical sampling and collection of surface materials on an AFM cantilever probe tip for real-time analysis directly from the AFM tip. This approach allows for material to be concentrated directly onto the probe for subsequent MS analysis. We evaluate the performance metrics of the technique and demonstrate localized MS sampling from a candelilla wax matrix containing UV stabilizers avobenzone and oxinoxate from areas down to 250 nm × 250 nm. Overall, this approach removes heat dissipation into the bulk material allowing for a faster desorption and concentration of the gas phase analyte from a single heating pulse enabling higher signal levels from a given amount of material in a single sampling spot.Graphical abstract.

The weather condition and epidemics as triggers for febrile seizure: A single-center retrospective observational study

OBJECTIVE

The objective of this study was to investigate the association between the weather and epidemic condition and risk of febrile seizures (FSs) in Japan.

STUDY DESIGN

This single-center, retrospective study included 560 children (age, 6-60 months) with FSs who were transported to our center by ambulance from January 2011 through December 2018. The weather (temperature, atmospheric pressure, relative air humidity, amount of rainfall, sunshine duration, and air concentration of nitrogen dioxide [NO₂] and sulfur dioxide [SO₂]) and epidemic (influenza virus infection, infectious gastroenteritis, and exanthem subitum) conditions in this region were compared between the periods (days or weeks) with the transportation of children with FS to our hospital and those without such transportation.

RESULTS

In the univariate analyses, neither daily or weekly weather condition nor weekly epidemic condition was correlated to FS transportation. Furthermore, the multiple logistic regression analysis suggested that epidemic influenza virus infection (odds ratio [OR], 1.34; 95% confidence interval [CI], 1.08-1.73) and infectious gastroenteritis (OR, 1.64; 95% CI, 1.09-2.54) were the independent risk factors for FS occurrence and weather condition was not associated with FS risk.

CONCLUSIONS

Febrile seizure incidence may be increased by epidemic febrile infections but not by weather condition.

The effect of atmospheric pressure on oxygen saturation and dyspnea: the Tromsø study

A drop in atmospheric pressure, as observed at high altitudes, leads to decreased oxygen saturation. The effect of regular changes in barometric pressure at sea level has never been studied in a general population. A cohort of adults aged 40 years were examined with pulse oximetry at two separate visits, and the local barometric pressure was available from the local weather station. The study aimed at determining the effect of atmospheric pressure on oxygen saturation also called SpO₂, as well as on shortness of breath. Based on spirometry, the participants were divided into two groups, with normal and decreased lung function. Decreased lung function was defined as forced expiratory volume in 1 s (FEV₁) below lower limit or normal (LLN) or FEV₁/FVC (FVC, forced vital capacity) below LLN, with GLI 2012 reference values. The statistical analysis included uni/multivariable linear and logistic regression. A total of 7439 participants of the Tromsø 7 cohort study were included. There was a significant association between barometric pressure and SpO₂ < 96%, and we found that a reduction of 166.67 hPa was needed to get a 1% reduction in SpO₂. The change in atmospheric pressure was not significantly associated with shortness of breath, also not in subjects with reduced lung function.

Dependence of odontogenic abscess on meteorological parameters: truth or myth?

OBJECTIVES

It is still a common belief among dental practitioners that odontogenic abscesses are somehow linked to meteorological parameters. We investigated the influence of different meteorological parameters on the type of surgical abscess treatment (intra- versus extraoral incision) as a measure of the weather-dependent severity of infection.

MATERIALS AND METHODS

In this retrospective cohort study, we analyzed 841 patients who presented at our outpatient clinic with an odontogenic abscess between 2004 and 2013.

RESULTS

We found no statistical dependence between intra- versus extraoral abscess incision with regard to temperature, atmospheric pressure, or relative air humidity. The annual distribution of abscesses was even, and the number of abscesses with greater or lesser mean values of each meteorological parameter did not differ significantly.

CONCLUSIONS

Our results showed no statistical relationship between meteorological parameters and intra- or extraoral abscess incisions.

CLINICAL RELEVANCE

Our analysis supports the assumption that the theorized relationship between odontogenic abscesses and meteorological parameters remains a myth.

Analysis of weather exposure 7 days before occurrence of ST-segment elevation myocardial infarction

BACKGROUND

Several studies have highlighted the relationship between weather patterns and the occurrence of ST-elevation myocardial infarction (STEMI).

AIM

To evaluate the statistical association between the occurrence of STEMI and meteorological variables over the preceding 7 days.

METHODS

This was a retrospective study, using prespecified data from the ORBI (Breton Regional Observatory on Myocardial Infarction) registry, which includes all consecutive patients hospitalized for STEMI in the geographical area of Brest, France. Over a 7-year period, we compared the number of STEMIs per week with the mean values of meteorological variables over the preceding 7 days.

RESULTS

Overall, 7517 patients with STEMI were recorded in the ORBI registry between January 2009 and January 2016. After exclusion of patients not living in the geographical area of interest, 742 patients were included. The weekly incidence of STEMI ranged from 0 to 7 (median 2, interquartile range 1-3). In the univariate analysis, air temperature (odds ratio [OR] 1.05, 95% confidence interval [CI] 1.005-1.01 per 1°C decrease; P=0.03) and atmospheric pressure (OR 1.03, 95% CI 1.01-1.06 per 1 hPa increase; P=0.008) were associated with the weekly incidence of STEMI. In the multivariable analysis, air temperature (OR 1.06, 95% CI 1.01-1.10 per 1°C decrease; P=0.01), atmospheric pressure (OR 1.05, 95% CI 1.02-1.08 per 1 hPa increase; P<0.001) and duration of humidity>80% (OR 1.09, 95% CI 1.02-1.15 per 1hour increase; P=0.007) in the previous 7 days were associated with the occurrence of STEMI.

CONCLUSIONS

In this specific geographical area, occurrence of STEMI was statistically associated with a decrease in air temperature, an increase in atmospheric pressure and an increase in humidity over the preceding 7-day period.

Meteorological Variation Is a Predisposing Factor for Aneurismal Subarachnoid Hemorrhage: A 5-Year Multicenter Study in Fuzhou, China

OBJECTIVE

The climatic characteristics of aneurysmal subarachnoid hemorrhage (aSAH) have been reported, but consensus has not yet been reached. It is of great significance to elucidate the relationships between meteorological variation and aSAH in regions with specific climate patterns. We analyzed the occurrence of aSAH in the capital city of Fujian Province, China, through a multicenter, 5-year study, and aimed to reveal the meteorological influences on aSAH in the coastal city of eastern Fujian under the subtropical marine monsoon condition.

METHODS

A total of 2555 consecutive patients with aSAH in Fuzhou were collected using specialized stroke admission database from January 2013 to December 2017. Meteorological parameters including temperature, atmospheric pressure, and humidity were obtained from China Surface Meteorological Station during the same period. Poisson regression was used to explore the association between meteorological parameters and aSAH to calculate the incidence rate ratios (IRRs) with corresponding 95% confidence intervals (CIs). Generalized additive model analysis further revealed the nonlinear relationships between weather and aSAH.

RESULTS

Daily minimum temperature (IRR 0.976, 95% CI 0.958-0.996) and maximum pressure (IRR 1.022, 95% CI 1.001-1.042) were independently correlated with the onset of aSAH. Low temperature (below 16°C) and excessive atmospheric pressure (above 1008 hPa) increased the risk of aSAH. In addition, March in spring and December in winter were the 2 ictus peaks in Fuzhou throughout the year.

CONCLUSIONS

Cold and excessive atmospheric pressure are triggers for the occurrence of aSAH; March in spring and December in winter are the predominant onset periods in Fuzhou.

Effects of heat on first-ever strokes and the effect modification of atmospheric pressure: A time-series study in Shenzhen, China

BACKGROUND

Stroke is a leading cause of death globally. Extreme temperatures may induce stroke, but evidence on the effects of heat on first-ever strokes is not clear. Low air pressure can lead to depression and an increase in blood pressure, and it may exacerbate the health impact of heat. In this study, we aimed to evaluate the effects of heat on first-ever strokes, the possible sensitive populations, and the effect of modification of atmospheric pressure.

METHODS

We collected data on 142,569 first-ever strokes during 2005-2016 in Shenzhen, a coastal city in southern China, with subtropical oceanic monsoon climate. We fitted a time-series Poisson model in our study, estimating the association between daily mean temperature and first-ever strokes in hot months, with a distributed lag non-linear model with 7 days of lag. We calculated strokes attributable to heat in various gender, age groups, household register types, stroke subtypes, and atmospheric pressure levels.

RESULTS

Heat had a significant cumulative association with first-ever strokes, and the risk of strokes increased with the rise in temperature after it was higher than 30 °C (the 85th percentile). In total, 1.95% (95% empirical CI 0.63-3.20%) of first-ever strokes were attributable to high temperature. The attributable fraction and attributable number of heat were statistically significant in male, female, middle-aged and old patients, immigrant patients, and CBI patients. The fraction attributable to heat was 3.33% in the low atmospheric pressure group, and the number of estimated daily attributable strokes at low atmospheric pressure levels was higher than that of medium and high atmospheric pressure levels (p < 0.01).

CONCLUSIONS

High temperatures in hot months may trigger first-ever strokes, and low atmospheric pressure may exacerbate the effect. We mainly found associations between heat and first-ever strokes for intracerebral hemorrhage, middle-aged and old patients, as well as immigrant patients.

350 años de la medicina hiperbárica: aspectos históricos, fisiopatogénicos y terapéuticos

The early use of hyperbaric therapy started with the quest to relieve respiratory problems among inhabitants of large cities during the industrial revolution, and from this, we have explored the benefits of treatment with hyperbaric oxygen in different areas of medicine. With the advances of the medical sciences, our knowledge concerning the therapies with hyperbaric oxygenation certainly has broadened and hyperbaric medicine still intrigues the contemporary medical researchers that are in seek of improve the quality of life of their patients.

Following in the footsteps of Hippocrates-interrelation between the incidence of odontogenic abscess and meteorological parameters

OBJECTIVES

Although many physicians in daily practice assume a connection between odontogenic infections and meteorological parameters, this has not yet been scientifically proven. Therefore, the aim of the present study was to evaluate the incidence of odontogenic abscess (OA) in relation to outdoor temperature and atmospheric pressure.

PATIENTS AND METHODS

An analysis of patients with an odontogenic abscess who presented at the emergency department within a period of 24 months was performed. Only patients who had not received surgical or antibiotic treatment prior to presentation and who lived in Berlin/Brandenburg were included. The OA incidence was correlated with the mean/maximum outdoor temperature and atmospheric pressure starting from 14 days before presentation. The statistical analysis was carried out using Poisson regression models with OA incidence as dependent and meteorological parameters as independent variables.

RESULTS

A total of 535 patients (mean age 39.4 years; range 1 to 95 years) with 538 cases were included. Of these, 227 were hospitalized. The most frequent diagnosis was a canine fossa abscess. A significant association between mean (p = 0.0153) and maximum temperature (p = 0.008) on the day of the presentation and abscess incidence was observed. Furthermore, a significant correlation between OA incidence and maximum temperature 2 days before presentation was found (p = 0.034). The deviation of the mean temperature on the day of the presentation from the monthly mean temperature had a significant influence (p = 0.021) on the incidence of OA. In contrast to temperature, atmospheric pressure had no significant influence on the incidence of OA.

CONCLUSION

This study supports a relationship between the incidence of odontogenic abscess and outdoor temperature, but not atmospheric pressure. A significantly higher frequency of patients with an OA presented at our emergency department on days with (comparably) low and high outdoor temperatures. Furthermore, a significant correlation between incidence and maximum temperature 2 days before presentation was found.

CLINICAL RELEVANCE

The treatment of odontogenic infections has become a significant economic burden to public health care facilities. The results of this study may help to adapt the numbers of doctors/dentists on duty in relation to different weather conditions. In any case, it is an impetus to think outside the box.

[The relationship between the occurrence of spontaneous pneumothorax and atmospheric pressure]

INTRODUCTION

This study analyzes the relationship between the occurrence of spontaneous pneumothorax and atmospheric pressure.

PATIENTS AND METHODS

We conducted a retrospective study on 74 patients hospitalized for spontaneous pneumothorax in the department of respiratory diseases from the Ibn Roshd university hospital of Casablanca between January 2013 and June 2014. The value of atmospheric pressure at the time of the occurrence of pneumothorax was recorded and analyzed.

RESULTS

The mean age was 46 years with 70 men and 4 women. Eighty-one percent of patients were smokers and 89% lived in an urban zone. Overall, 79.7% of pneumothoraces occurred in anticyclonic conditions, with a median atmospheric pressure of 1018 hPa±4.18. In all, 12.2% of pneumothoraces occurred in atmospheric depression with a median atmospheric pressure of 1010 hPa±1.92. The remaining 8.1% occurred in isobaric conditions. Pneumothoraces occurred significantly more during periods of high pressure compared to other periods (P<0.001; odds ratio: 28.41; relative risk 6.56 [3.52<RR<12.22]). There was no difference in the age, number pf patients with chronic obstructive pulmonary disease or idiopathic pneumothorax between the atmospheric condition groups.

CONCLUSION

Increased atmospheric pressure is a risk factor for spontaneous pneumothorax independent of age or the presence of underlying lung disease.

First application of atmospheric-pressure chemical ionization gas chromatography tandem mass spectrometry to the determination of cannabinoids in serum

The analysis of cannabinoids in blood samples is still a challenging issue for forensic laboratories, because of the low concentrations to be determined to prove that a person acted under CannabisTherefore, sensitive analytical techniques are required. This study presents the development and validation of a novel APGC-MS/MS method for the simultaneous determination of Δ9-tetrahydrocannabinol (THC), 11-hydroxy- Δ9-THC (THC-OH), 11-nor-9-carboxy- Δ9-THC (THCA), cannabidiol (CBD), cannabidiol acid (CBDA) and cannabigerol (CBG) in human serum. The developed method was fully validated according to international guidelines, with evaluation of selectivity, precision, accuracy, linearity, LODs and LOQs, extraction recovery and matrix effect. The method was linear in the range 0.2-25 ng/mL for THC, THC-OH, CBD and CBG, while for THCA and CBDA linearity was assessed in the range of 0.8-100 ng/mL and 3-100 ng/mL, respectively. The LOQs were determined in 0.2 ng/mL for THC, 0.4 ng/mL for THC-OH, 0.8 ng/mL for CBD and CBG, 1.6 ng/mL for THCA and 3 ng/mL for CBDA. The method was applied to the analysis of 15 serum samples from DUID cases. To the best of our knowledge, the present work is the first one describing an application of APGC source in the field of forensic toxicology.

Seasonal incidence of ruptured abdominal aortic aneurysm and the influence of atmospheric pressure: a systematic review and meta-analysis

Ruptured abdominal aortic aneurysm (rAAA) is a life-threatening condition with a high mortality rate. Seasonal variations in the incidence of rAAA and the influence of atmospheric pressure have been studied throughout decades; however, the conclusions are contradictory. Therefore, we aimed to conduct a meta-analysis and systematic review of literature on seasonal variations in rAAA incidence and the influence of atmospheric pressure. Studies investigating seasonal variations in rAAA incidence and influence of atmospheric pressure were retrieved. For dichotomous data, we generated risk ratios (RRs) and 95% confidence intervals (CIs) for rAAA incidence compared among seasons. The studies were subdivided according to latitude, elevation, and climatic types, for subgroup comparisons. Studies reporting monthly incidence and seasonal mortality were further investigated. For continuous data, standardized mean differences (SMDs) and 95% CIs were generated for atmospheric pressure comparisons. Twenty-four eligible studies were included, comprising a total of 38,506 patients with rAAA. Pooled rAAA incidence was 25% in spring, 23% in summer, 26% in autumn, and 26% in winter. Pooled analysis demonstrated a statistically significant higher rAAA incidence in winter than in summer (RR 1.10, P = 0.04) and in autumn than in summer (RR 1.11, P < 0.00001). However, there was no statistically significant difference among other seasons. In the study of the influence of atmospheric pressure, no statistically significant difference was observed. In conclusion, our study revealed a higher incidence of rAAA in autumn and winter than in summer; however, atmospheric pressure was found to exert no influence.

Influence of meteorological factors on the onset of primary spontaneous pneumothorax

Introduction Although links between meteorological conditions and primary spontaneous pneumothorax have been proposed, the reports are controversial. The aim of the study is to correlate between climatic changes and the development of this condition. Materials and methods A retrospective chart review included all patient presenting with primary spontaneous pneumothorax to King Fahd Hospital, Imam Abdulrahman Bin Faisal University, Alkhobar, Saudi Arabia, from 1 January 2005 to 31 December 2016. Meteorological data were collected from King Abdulaziz airbase station using an online source for the same time interval. The data were analysed to determine differences in weather conditions between days on which primary spontaneous pneumothorax occurred and those in which it did not. Logistic regression model was used to obtain predicted risks for the onset of primary spontaneous pneumothorax with respect to weather conditions. Result Two hundred and eighty-nine patients were found to have primary spontaneous pneumothorax in the 281 days included in the study. Among the meteorological parameters, significant differences were found in average temperature and atmospheric pressure difference between day of admission and two days before the admission, between days with primary spontaneous pneumothorax and days without. There was no significant difference in the other meteorological factors between days with primary spontaneous pneumothorax and days without. Conclusion Two hundred and eighty-nine patients were found to have primary spontaneous pneumothorax in the 281 days included in the study. Among the meteorological parameters, significant differences were found in average temperature and atmospheric pressure difference between day of admission and two days before the admission, between days with primary spontaneous pneumothorax and days without. There was no significant difference in the other meteorological factors between days with primary spontaneous pneumothorax and days without.

Correlation between meteorological changes and primary spontaneous pneumothorax: Myth or fact?

Background

This study aims to investigate the relationship between meteorological changes and the development of primary spontaneous pneumothorax.

Methods

Medical records of 1,097 patients ( 975 males, 122 females; mean age 23.5±4.2 years; range, 17 to 32 years) admitted to our hospital with a diagnosis of primary spontaneous pneumothorax between January 2010 and January 2014 were evaluated retrospectively. Daily mean values for air temperature, wind speed, humidity rate and atmospheric pressure values obtained from the local meteorological observatory were recorded. The four-year study period was separated into two groups as days with at least one primary spontaneous pneumothorax development (group 1) and days without any primary spontaneous pneumothorax development (group 2).

Results

Within the study period of a total of 1,461 days, 1,097 cases were recorded in 759 days during which primary spontaneous pneumothorax was observed. Eighty-nine percent of the patients were male. There was no significant difference between the groups in terms of mean air temperature, humidity rate, and wind speed. Atmospheric pressure was significantly lower in group 1 (p<0.001). Decrease in atmospheric pressure with respect to the previous day increased the risk of primary spontaneous pneumothorax development significantly (p<0.001).

Conclusion

In our study, low atmospheric pressure and significant pressure decreases showed a strong correlation with primary spontaneous pneumothorax. Temperature, wind speed, and humidity values did not influence primary spontaneous pneumothorax development.

Citius, Altius, Fortius: Agreement between Perkins and Dynamic Contour Tonometry (Pascal) and the Impact of Altitude

Introduction

To ascertain differences in intraocular pressure (IOP) measurement and their repeatability between dynamic contour tonometry (DCT) and Goldmann/Perkins applanation tonometry (GAT) at two different atmospheric pressures.

Materials and methods

Forty-one eyes of 41 healthy consenting subjects were enrolled for this observational, cross-sectional study. Pachymetry and IOP measurements with DCT and GAT for both eyes of each subject at Acapulco (0 m from sea level) and at Mexico City (2,234 m from sea level) were done by the same observer. The IOP was compared between tonometers at each of the altitudes, and also for repeatability of each tonometer at different altitudes. Pearson's correlation coefficient and Bland-Altman plots were used to assess reliability of measurements and their differences at the two altitudes.

Results

The mean age of patients was 41.7 (28-66 years); 22 were females. Mean IOP with DCT was 16.1 ± 2.2 mm Hg at sea level and 15.9 ± 2.1 mm Hg at 2,234 m above sea level, not a significant difference. Mean GAT IOP at the two altitudes was 13.1 ± 1.8 and 11.5 ± 1.7 mm Hg respectively, a statistically sig -nificant difference. In contrast, central corneal thickness (CCT) was not significantly changed (548.3 to 549.4 μm, p = 0.496).

Conclusion

Repeatability of single-observer measurements with GAT remains clinically acceptable, but not at different altitudes. The DCT seems to more consistently measure a similar IOP at different altitudes in the same subjects. The two tonometers may not be used interchangeably in the serial follow-up of patients at any of the altitudes.How to cite this article: Albis-Donado O, Bhartiya S, Gil-Reyes M, Casale-Vargas G, Arreguin-Rebollar N, Kahook MY. Citius, Altius, Fortius: Agreement between Perkins and Dynamic Contour Tonometry (Pascal) and the Impact of Altitude. J Curr Glaucoma Pract 2018;12(1):40-44.

Air pollutants and atmospheric pressure increased risk of ED visit for spontaneous pneumothorax

OBJECTIVE

To investigate the impact of short-term exposure to air pollutants and meteorological variation on ED visits for primary spontaneous pneumothorax (PSP).

MATERIAL AND METHODS

We retrospectively identified PSP cases that presented at the ED of our tertiary center between January 2015 and September 2016. We classified the days into three types: no PSP day (0 case/day), sporadic days (1-2 cases/day), and cluster days (PSP, ≥3 cases/day). Association between the daily incidence of PSP with air pollutants and meteorological data were determined using Poisson generalized-linear-model to calculate incidence rate ratio (IRRs) and the use of time-series (lag-1 [the cumulative air pollution level on the previous day of PSP], lag-2 [two days ago], and lag-3 [three days ago]).

RESULTS

Using multivariate logistic regression analysis, O₃ (p = 0.010), NO₂ (p = 0.047), particulate matters (PM)₁₀ (p = 0.021), and PM_2.5 (p = 0.008) were significant factors of PSP occurrence. When the concentration of O₃, NO₂, PM₁₀, and PM_2.5 were increased, PSP IRRs increased approximately 15, 16, 3, and 5-fold, respectively. With the time-series analyses, atmospheric pressure in lag-3 was significantly lower and in lag-2, was significantly higher in PSP days compared with no PSP days. Among air pollutant concentrations, O₃ in lag-1 (p = 0.017) and lag-2 (p = 0.038), NO₂ in lag-1 (p = 0.015) and lag-2 (p = 0.009), PM₁₀ in lag-1 (p = 0.012), and PM_2.5 in lag-1 (p = 0.021) and lag-2 (p = 0.032) were significantly different between no PSP and PSP days.

CONCLUSION

Increased concentrations of air pollutants and abrupt change in atmospheric pressure were significantly associated with increased IRR of PSP.

Room Air Readings of Brain Tissue Oxygenation Probes

OBJECTIVE

Brain tissue oxygenation (p_btO₂) monitoring with microprobes is increasingly used as an important parameter in addition to intracranial pressure in acutely brain-injured patients. Data on accuracy and long-term drift after use are scarce. We investigated room air readings of used p_btO₂ probes for their relationship with the duration of monitoring, geographic location of the center, and manufacturer type.

METHODS

After finishing clinically indicated monitoring in patients, p_btO₂ probes used in two centers in Berlin and Munich were explanted and cleaned to avoid blood contamination. Immediately afterward, room air readings of partial oxygen pressure (p_airO₂) from 44 Licox^® and 10 Raumedic ^® p_btO₂ probes were recorded. Assumed height above sea level was 42 m for Berlin and 485 m for Munich; this resulted in assumed theoretical p_airO₂ readings of 157.8 mmHg in Berlin and 149.9 mmHg in Munich.

RESULTS

Licox ^® probes in Berlin showed a mean p_airO₂ of 160.5 (SD 14.4) mmHg and of 147.8 (11.9) mmHg in Munich. Raumedic ^® probes in Berlin showed a mean p_airO₂ of 170.5 (12.2) mmHg and the single Raumedic ^® probe used in Munich 155 mmHg. No significant drift was found over time for probes with up to 14 days of monitoring. Prolonged use of up to 20 days showed a clinically negligible drift of 1.2 mmHg per day of use for Licox^® probes.Mean absolute deviation for p_airO₂ from expected values was 6.4% for Licox ^® and 9.7% for Raumedic ^® probes.

CONCLUSION

Room air partial oxygen pressure p_airO₂ may be utilized to assess the proper function of a p_btO₂ probe. It provides a tool for quality control which is easy to implement. Probe readings are stable in the clinically relevant range, even after prolonged use.

Ultrasonic assisted synthesis of BaTiO3 nanoparticles at 25 °C and atmospheric pressure

Barium titanate (BaTiO₃) nanoparticles were successfully synthesized via a sonochemical method (25 kHz) at a constant temperature of 25 °C and atmospheric pressure without a calcination step. Barium hydroxide Ba(OH)₂ and diisopropoxytitanium bis(acetylacetonate) (C₁₂H₂₈O₆Ti) were used as the starting materials. The effects of the concentration of NaOH used and ultrasonic reaction time were investigated. The phase composition, functional groups and morphology of synthesized powders were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Fourier transform Raman spectroscopy (FT-Raman) and transmission electron microscopy (TEM). The XRD and FT-Raman results revealed the cubic structure of BaTiO₃. The optimal NaOH concentration and ultrasonic reaction time for producing a narrow particle size distribution and the bowl-like structure of BaTiO₃ nanoparticles were 10 M and 1 h, respectively. TEM imagery showed their morphology as a monodispersed bowl-like structure with a size of 54.90 ± 18.18 nm. After longer ultrasonic contact times, the bowl-like structure tended to fracture forming irregularly shaped nano-sized BaTiO₃ particles.

Atmospheric Pressure Variation is a Delayed Trigger for Aneurysmal Subarachnoid Hemorrhage

OBJECTIVE

There is an ongoing search for conditions that induce spontaneous subarachnoid hemorrhage (SAH). The seasonal pattern of SAH is shown in a large meta-analysis of the literature, but its explanation remains undecided. There is a clear need for sound meteorologic data to further elucidate the seasonal influence on SAH. Because of the stable and densely monitored atmospheric situation in the north of the Netherlands, we reviewed our unique cohort on the seasonal incidence of SAH and the association between SAH and local atmospheric changes.

METHODS

Our observational cohort study included 1535 patients with spontaneous SAH admitted to our neurovascular center in the north of the Netherlands between 2000 and 2015. Meteorologic data could be linked to the day of the ictus. To compare SAH incidences over the year and to test the association with meteorologic conditions, incidence rate ratios (IRRs) with corresponding 95% confidence intervals (CIs) were used, calculated by Poisson regression analyses.

RESULTS

Atmospheric pressure variations were significantly associated with aneurysmal SAH. In particular, the pressure change on the second and third day before the ictus was independently correlated to a higher incidence of aneurysmal SAH (IRR, 1.11; 95% CI, 1.00-1.23). The IRR for aneurysmal SAH in July was calculated 0.67 (95% CI, 0.49-0.92) after adjustment for temperature and atmospheric pressure changes.

CONCLUSIONS

Atmospheric pressure variations are a delayed trigger for aneurysmal SAH. Also, a significantly decreased incidence of aneurysmal SAH was noted in July.

Effects of Temperature and Pressure on Acute Stroke Incidence Assessed Using a Korean Nationwide Insurance Database

Background and Purpose

Many studies have evaluated the association between weather and stroke, with variable conclusions. Herein we determined the relationships between daily meteorological parameters and acute stroke incidence in South Korea.

Methods

Patients with acute stroke (2,894) were identified by standard sampling of a nationwide insurance claims database from January to December 2011. We used multiple Poisson regression analyses of stroke incidence and meteorological parameters (mean temperature, diurnal temperature change, temperature differences over the preceding 24 hours, atmospheric pressure, humidity, wind speed, and physiologically equivalent temperature) to calculate the relative risk of stroke incidence associated with meteorological parameters.

Results

There were no seasonal variations in the incidences of ischemic (2,176) or hemorrhagic (718) stroke. Temperature change during the day was positively correlated with ischemic stroke in men (relative risk [RR] 1.027; 95% confidence interval [CI] 1.006–1.05) and older patients (≥65 years) (RR 1.031, 95% CI 1.011–1.052). Temperature differences over the preceding 24 hours had a negative correlation with all strokes (RR 0.968, 95% CI 0.941–0.996), especially among older women. Diurnal variation of atmospheric pressure was also significantly associated with the incidence of ischemic stroke (age<65 years, RR 1.051, 95% CI 1.011–1.092; age≥65 years, RR 0.966, 95% CI 0.936–0.997).

Conclusions

Diurnal temperature change, temperature differences over the preceding 24 hours, and diurnal variation of atmospheric pressure were associated with daily stroke incidence. These findings may enhance our understanding of the relationship between stroke and weather.

The major influence of the atmosphere on intracranial pressure: an observational study

The impact of the atmosphere on human physiology has been studied widely within the last years. In practice, intracranial pressure is a pressure difference between intracranial compartments and the surrounding atmosphere. This means that gauge intracranial pressure uses atmospheric pressure as its zero point, and therefore, this method of pressure measurement excludes the effects of barometric pressure's fluctuation. The comparison of these two physical quantities can only take place through their absolute value relationship. The aim of this study is to investigate the direct effect of barometric pressure on the absolute intracranial pressure homeostasis. A prospective observational cross-sectional open study was conducted in Szczecin, Poland. In 28 neurosurgical patients with suspected normal-pressure hydrocephalus, intracranial intraventricular pressure was monitored in a sitting position. A total of 168 intracranial pressure and atmospheric pressure measurements were performed. Absolute atmospheric pressure was recorded directly. All values of intracranial gauge pressure were converted to absolute pressure (the sum of gauge intracranial pressure and local absolute atmospheric pressure). The average absolute mean intracranial pressure in the patients is 1006.6 hPa (95 % CI 1004.5 to 1008.8 hPa, SEM 1.1), and the mean absolute atmospheric pressure is 1007.9 hPa (95 % CI 1006.3 to 1009.6 hPa, SEM 0.8). The observed association between atmospheric and intracranial pressure is strongly significant (Spearman correlation r = 0.87, p < 0.05) and all the measurements are perfectly reliable (Bland-Altman coefficient is 4.8 %). It appears from this study that changes in absolute intracranial pressure are related to seasonal variation. Absolute intracranial pressure is shown to be impacted positively by atmospheric pressure.

Tensile properties of the hip joint ligaments are largely variable and age-dependent - An in-vitro analysis in an age range of 14-93 years

INTRODUCTION

Hip joint stability is maintained by the surrounding ligaments, muscles, and the atmospheric pressure exerted via these structures. It is unclear whether the ligaments are capable of preventing dislocation solely due to their tensile properties, and to what extent they undergo age-related changes. This study aimed to obtain stress-strain data of the hip ligaments over a large age range.

METHODS

Stress-strain data of the iliofemoral (IL), ischiofemoral (IS) and pubofemoral ligament (PF) were obtained from cadavers ranging between 14 and 93 years using a highly standardized setting. Maximum strains were compared to the distances required for dislocation.

RESULTS

Elastic modulus was 24.4 (IL), 22.4 (IS) and 24.9N/mm² (PF) respectively. Maximum strain was 84.5%, 86.1%, 72.4% and ultimate stress 10.0, 7.7 and 6.5N/mm² for the IL, IS and PF respectively. None of these values varied significantly between ligaments or sides. The IS' elastic modulus was higher and maximum strain lower in males. Lower elastic moduli of the PF and higher maximum strains for the IS and PF were revealed in the ≥55 compared to the <55 population. Maximum strain exceeded the dislocation distance of the IS without external hip joint rotation in females, and of the IS and cranial IL under external rotation in both genders.

DISCUSSION

Tensile and failure load properties of the hip joint ligaments are largely variable. The IS and PF change age-dependently. Though the hip ligaments contribute to hip stability, the IS and cranial IL may not prevent dislocation due to their elasticity.

Weather-dependent microhabitat use by Tetrix tenuicornis (Orthoptera: Tetrigidae)

For ectothermic animals, selection of a suitable microhabitat is affected by a combination of abiotic and biotic factors. Also important is the trade-off between those microhabitats with optimal microclimatic conditions and food availability vs. those with the lowest level of competition and lowest risk of predation. Central European species of groundhoppers (Orthoptera: Tetrigidae) live in locations with small-scale mosaics of patches formed by bare ground, moss cushions and vascular plants (grasses and forbs). Our research focused on the effects of selected weather components (current temperature, humidity, atmospheric pressure and sunlight) on specific microhabitat selection by adults (during the reproductive season) and by the last-instar nymphs (during the non-reproductive season) of the groundhopper Tetrix tenuicornis. Using experimental conditions, we determined that microhabitat use by T. tenuicornis is sex-specific and that microhabitat preference differs between adults and nymphs. We suppose that microhabitats are used according to groundhopper current needs in relation to each habitat's suitability for maintaining body temperature, food intake and reproductive behaviour. Microhabitat preferences were significantly associated with temperature and atmospheric pressure. Changes in atmospheric pressure signal changes in weather, and insects respond to increases or decreases in pressure by adjusting their behaviour in order to enhance survival. We propose that, under low atmospheric pressure, T. tenuicornis actively seeks microhabitats that provide increased protection from adverse weather.

Do Meteorological Changes Have an Effect on The Occurence of Spontaneous Pneumothorax?

OBJECTIVES

Spontaneous pneumothorax refers to the leakage of air into the space between the parietal and the visceral layers of the pleura. It occurs with or without a known lung disease. We aimed to investigate the effects of atmospheric pressure, humidity, and temperature changes on the incidence of spontaneous pneumothorax (SP).

MATERIAL AND METHODS

This study included 551 patients with spontaneous pneumothorax retrospectively screened between January 2009 and December 2013. The medical data of the patients were accessed via their medical records on the hospital automation system. The atmospheric pressure, temperature, humidity rate, amount of precipitation, and wind velocity on the day of spontaneous pneumothorax were obtained from the data provided by the general directorate of meteorology. The three consecutive days on which at least 2 cases of SP presented were collectively considered as a cluster. The study data were analyzed with the SPSS version 15 software package, using the Chi-square and the Student's t tests. A p value less than 0.05 was considered statistically significant.

RESULTS

Of the 552 patients included in the study, 89.3% had primary spontaneous pneumothorax and 10.7% had secondary spontaneous pneumothorax. Ninety-two percent of the patients were male and 8% were female. The mean age was 24 years. Clustering was observed in 71.7% of the study population. No significant differences were observed between yearly and monthly SP incidences. There were, however, differences between the days with SP and the days without SP with respect to atmospheric pressure, ambient temperature, wind velocity, and humidity rate. The differences between the atmospheric pressures were not statistically significant, although the differences between the ambient temperature and the humidity rate were statistically significant (p≤ 0.05).

CONCLUSION

We determined that the changes in the ambient temperature and the humidity rate affected the rate of spontaneous pneumothorax by altering the meteorological conditions.

Spectroscopic and electrical characters of SBD plasma excited by bipolar nanosecond pulse in atmospheric air

In this paper, an atmospheric surface barrier discharge (SBD) generated by annular electrodes in quartz tube is presented through employing bipolar nanosecond pulse voltage in air. The discharge images, waveforms of pulse voltage and discharge current, and optical emission spectra emitted from the discharges are recorded and calculated. A spectra simulation method is developed to separate the overlap of the secondary diffraction spectra which are produced by grating in monochromator, and N2 (B(3)Πg→A(3)Σu(+)) and O (3p(5)P→3s(5)S2(o)) are extracted. The effects of pulse voltage and discharge power on the emission intensities of OH (A(2)Σ(+)→X(2)Пi), N2(+) (B(2)Σu(+)→X(2)Σg(+)), N2 (C(3)Πu→B(3)Πg), N2 (B(3)Πg→A(3)Σu(+)), and O (3p(5)P→3s(5)S2(o)) are investigated. It is found that increasing the pulse peak voltage can lead to an easier formation of N2(+) (B(2)Σu(+)) than that of N2 (C(3)Πu). Additionally, vibrational and rotational temperatures of the plasma are determined by comparing the experimental and simulated spectra of N2(+) (B(2)Σu(+)→X(2)Σg(+)), and the results show that the vibrational and rotational temperatures are 3250±20K and 350±5K under the pulse peak voltage of 28kV, respectively.

Climatic variations and benign paroxysmal positional vertigo

Benign paroxysmal positional vertigo (BPPV) is probably the most common diagnosis at vertigo clinics. Seasonal cycles of several human illnesses could be attributed variously to changes in atmospheric or weather conditions. In this retrospective study, patients with BPPV from January 2010 to December 2012 were studied, and their charts were reviewed. Statistical analysis revealed a statistically significant difference in patients' numbers among different months of the year. Also there is a significant statistical correlation between the numbers of patients with climatic variations especially the temperature. The present paper discusses the possible explanations for these results which confirms the seasonal variations in BPPV, together with a review of literature to view the possible associations with other disorders that causes such seasonality.

Stability of plasma treated superhydrophobic surfaces under different ambient conditions

Plasma hydrophilizing of superhydrophobic substrates has become an important area of research, for example, superhydrophobic-(super)hydrophilic patterned surfaces have significant practical applications such as lab-on-chip systems, cell adhesion, and control of liquid transport. However, the stability of plasma-induced hydrophilicity is always considered as a key issue since the wettability tends to revert back to the untreated state (i.e. aging behavior). This paper focuses on the stability of plasma treated superhydrophobic surface under different ambient conditions (e.g. temperature and relative humidity). Water contact angle measurement and X-ray photoelectron spectroscopy are used to monitor the aging process. Results show that low temperature and low relative humidity are favorable to retard the aging process and that pre-storage at low temperature (-10°C) disables the treated surface to recover superhydrophobicity. When the aging is performed in water, a long-lasting hydropholicity is obtained. As the stability of plasma-induced hydrophilcity over a desired period of time is a very important issue, this work will contribute to the optimization of storage conditions of plasma treated superhydrophobic surfaces.

Intense methane ebullition from open water area of a shallow peatland lake on the eastern Tibetan Plateau

Methane fluxes from a shallow peatland lake (3450 m a.s.l., 1.6 km(2) in area, maximum depth <1m) on eastern Tibetan Plateau were measured with floating chamber method during May to August, 2009. The overall average of methane emission rate during the study period was 34.71±29.15 mg CH4 m(-2) h(-1). The occurrence of ebullition among the overall methane flux from Lake Medo was about 74%. The average rate of ebullition was 32.45±28.31 mg CH4 m(-2) h(-1), which accounted for 93% of the overall average of methane emission. Significant seasonal variation was found for occurrence (P<0.05) and rate (P<0.01) of ebullition, both peaking synchronously in mid-summer. Both the occurrence and rate of ebullition were found positively related to sediment temperature but negatively related to lake water depth. The high methane production in the lake sediment was likely fueled by organic carbon loaded from surrounding peatlands to the lake. The shallowness of the water column could be another important favorable factor for methane-containing bubble formation in the sediment and their transportation to the atmosphere. The methane ebullition must have been enhanced by the low atmospheric pressure (ca. 672 hPa) in the high-altitude environment. For a better understanding on the mechanism of methane emission from alpine lakes, more lakes on the Tibetan Plateau should be studied in the future for their methane ebullition.

Correlation between suicide and meteorological parameters

OBJECTIVE

The aim of this study was to investigate the link between suicide and meteorological parameters in the 23 wards of Tokyo, Japan.

MATERIALS AND METHODS

Monthly data (from January 2008 to December 2012) of suicide stratified by the type of suicide, i.e. hanging, drowning and jumping, were obtained from the Tokyo Medical Examiner's Office official web site. Monthly meteorological parameters (atmospheric pressure, air temperature, humidity and daylight hours) in the 23 wards of Tokyo were also used for the required period. The effects of meteorological parameters on suicide were explored.

RESULTS

The number of suicides was 110.4±14.7 (80-149) for men and 55.6±9.1 (41-87) for women in the 23 wards of Tokyo, Japan. The mean air temperature was 16.6°C±7.7 °C (4.8-29.6 °C). The number of suicides by drowning for men was significantly and positively correlated with air temperature, and weakly and positively correlated with humidity. In addition, the number of suicides by drowning for men was significantly and negatively correlated with atmospheric pressure.

CONCLUSIONS

The number of suicides by drowning was associated with meteorological parameters, especially in men, in the 23 wards of Tokyo, Japan.

Do Weather Phenomena Have Any Influence on the Occurrence of Spontaneous Pneumothorax?

INTRODUCTION

The objective of this study was to assess the impact of weather phenomena on the occurrence of spontaneous pneumothorax (SP) in the Plzeň region (Czech Republic).

METHODS

A retrospective analysis of 450 cases of SP in 394 patients between 1991 and 2013. We observed changes in average daily values of atmospheric pressure, air temperature and daily maximum wind gust for each day of that period and their effect on the development of SP.

RESULTS

The risk of developing SP is 1.41 times higher (P=.0017) with air pressure changes of more than±6.1hPa. When the absolute value of the air temperature changes by more than±0.9°C, the risk of developing SP is 1.55 times higher (P=.0002). When the wind speed difference over the 5 days prior to onset of SP is less than 13m/sec, then the risk of SP is 2.16 times higher (P=.0004). If the pressure difference is greater than±6.1hPa and the temperature difference is greater than±0.9°C or the wind speed difference during the 5 days prior to onset of SP is less than 10.7m/s, the risk of SP is 2.04 times higher (P≤.0001).

CONCLUSION

Changes in atmospheric pressure, air temperature and wind speed are undoubtedly involved in the development of SP, but don't seem to be the only factors causing rupture of blebs or emphysematous bullae.

Do atmospheric conditions influence the first episode of primary spontaneous pneumothorax?

OBJECTIVES

Several studies suggest that changes in airway pressure may influence the onset of primary spontaneous pneumothorax (PSP). The aim of this study was to investigate the influence of atmospheric changes on the onset of the first episode of PSP.

METHODS

We retrospectively analysed cases of pneumothorax admitted to our department between 1 January 2009 and 31 October 2013. Patients with recurrent pneumothorax, traumatic pneumothorax, older than 35 years or presenting history of underlying pulmonary disease were excluded. Meteorological data were collected from the Météo-France archives. Variation (Δ) of mean atmospheric pressure, and relative humidity, were calculated for each day between the day at which symptoms began (D-day), the day before first symptoms (D-1), 2 days before the first symptoms (D-2) and 3 days before the first symptoms (D-3).

RESULTS

Six hundred and thirty-eight cases of pneumothorax were observed during the period of this study; 106 of them (16.6%) were a first episode of PSP. We did not observe any significant differences between days with or without PSP admission for any of the weather parameters that we tested. We could not find any thresholds in the variation of atmospheric pressure that could be used to determine the probability of PSP occurrence.

CONCLUSIONS

Variation of atmospheric pressure, relative humidity, rainfall, wind speed and temperature were not significantly related to the onset of the first episode of PSP in healthy patients. These results suggest that the scientific community should focus on other possible aetiological factors than airway pressure modifications.

Magnetic storms and variations in hormone levels among residents of North Polar area--Svalbard

In the present work four examinations (January, March, June, October 1991-1992) of the blood concentration of adrenal hormones (cortisol) and thyroid hormones (triiodothyronine (T3) and thyroxine T4) and their dependence on space and terrestrial weather parameters have been done for large groups of healthy inhabitants of high latitudes (Svalbard, the most northerly in the world year-round inhabited settlements). The aim of this study was to find the possible sensitivity of these biochemical parameters to variations of external natural factors at high latitudes in three independent groups of people living in this region (miners and people working underground (364 samples), the men working on the ground (274 samples) and women working on the ground (280 samples)). The obtained data indicate that the most expressed dependence of concentration of the three studied hormones is on the level of geomagnetic activity (GMA) - Kp, Ap, Kpmax - 3h. For two of the four seasons (June and October) with increasing levels of GMA a significant (p<0.05) increase in cortisol concentration in all three independent groups of people was observed. Range of increases in cortisol concentration in different groups were about 30% of the observed variation in the average intragroup concentration in June and from 16% to 38% in October. For T3 dependence was found only in June: drop in hormone secretion with increasing levels of GMA from 18 to 30% of the average range of intragroup variations. Thus it was shown for the first time that at high geographical latitudes with increased level of GMA a significant change in the level of secretion of several hormones leads to the type of adaptive stress reaction.

The impact of relative humidity and atmospheric pressure on mortality in Guangzhou, China

OBJECTIVE

Although many studies have examined the effects of ambient temperatures on mortality, little evidence is on health impacts of atmospheric pressure and relative humidity. This study aimed to assess the impacts of atmospheric pressure and relative humidity on mortality in Guangzhou, China.

METHODS

This study included 213,737 registered deaths during 2003-2011 in Guangzhou, China. A quasi-Poisson regression with a distributed lag non-linear model was used to assess the effects of atmospheric pressure/relative humidity.

RESULTS

We found significant effect of low atmospheric pressure/relative humidity on mortality. There was a 1.79% (95% confidence interval: 0.38%-3.22%) increase in non-accidental mortality and a 2.27% (0.07%-4.51%) increase in cardiovascular mortality comparing the 5th and 25th percentile of atmospheric pressure. A 3.97% (0.67%-7.39%) increase in cardiovascular mortality was also observed comparing the 5th and 25th percentile of relative humidity. Women were more vulnerable to decrease in atmospheric pressure and relative humidity than men. Age and education attainment were also potential effect modifiers. Furthermore, low atmospheric pressure and relative humidity increased temperature-related mortality.

CONCLUSION

Both low atmospheric pressure and relative humidity are important risk factors of mortality. Our findings would be helpful to develop health risk assessment and climate policy interventions that would better protect vulnerable subgroups of the population.

[The relationship between aneurysmal subarachnoid hemorrhage and meteorological parameters based on a series of 236 French patients]

Subarachnoid hemorrhage (SAH) is a sudden and potentially severe event with mortality rates ranging between 24 and 30 % depending on the initial clinical condition. Studies have attempted to assess the possible influence of meteorological parameters on the occurrence of SAH. However, this idea remains very controversial and the results vary widely from one study to another. Our study is the second largest French series, and first performed in a homogeneous series of patients. The aim of our study was to attempt to establish a relationship between the weather (i.e.) temperature variations and daily variations of atmospheric pressure in the days before the onset of SAH and the same day and the occurrence of non-traumatic SAH in a homogeneous population of 236 patients from a single center, over a period of 7 years (2002 to 2008). This retrospective study does not suggest any relationship between the occurrence of SAH and meteorological data studied. Moreover, no relationship was observed between mean changes in temperature or pressure and the occurrence of SAH, that the day of the bleeding or the days preceding the SAH. However, a female predominance was observed and a relatively high mortality rate of 18.3 %. The distribution of the occurrence of an SAH was random. As it seems impossible to provide logistics and organization of care for non-traumatic SAH, the care system must remain vigilant throughout the year.

Suitability of commercial barometric pressure sensors to distinguish sitting and standing activities for wearable monitoring

Despite its medical relevance, accurate recognition of sedentary (sitting and lying) and dynamic activities (e.g. standing and walking) remains challenging using a single wearable device. Currently, trunk-worn wearable systems can differentiate sitting from standing with moderate success, as activity classifiers often rely on inertial signals at the transition period (e.g. from sitting to standing) which contains limited information. Discriminating sitting from standing thus requires additional sources of information such as elevation change. The aim of this study is to demonstrate the suitability of barometric pressure, providing an absolute estimate of elevation, for evaluating sitting and standing periods during daily activities. Three sensors were evaluated in both calm laboratory conditions and a pilot study involving seven healthy subjects performing 322 sitting and standing transitions, both indoor and outdoor, in real-world conditions. The MS5611-BA01 barometric pressure sensor (Measurement Specialties, USA) demonstrated superior performance to counterparts. It discriminates actual sitting and standing transitions from stationary postures with 99.5% accuracy and is also capable to completely dissociate Sit-to-Stand from Stand-to-Sit transitions.

The influencing factors of nanosecond pulse homogeneous dielectric barrier discharge in air

In this paper, a bipolar nanosecond high pulse voltage with 20 ns rising time was employed to generate homogeneous dielectric barrier discharges using the plate-plate electrode configuration in air at atmospheric pressure. The effects of pulse peak voltage, gas discharge gap, and dielectric plates made by different materials or thicknesses on the discharge homogeneity, voltage-current waveform, and optical emission spectra were investigated. Results show that aforementioned parameters have a strongly impact on the discharge homogeneity and the optical emission spectra, but it is hard to identify definitely their influences on the discharge voltage-current waveform. Homogeneous discharges were easily observed when using low permittivity dielectric plate and the emission intensity of N2 (C(3)Πu→B(3)Πg, 0-0, 337.1 nm) increases with the rising of pulse peak voltage and the permittivity of dielectric material but decreases with the increasing of gas discharge gap and the dielectric plate thickness. The rotational and vibrational temperatures (Trot and Tvib) were determined at Trot=350±5 K and Tvib=3045 K via fitting the simulative spectra of N2 (C(3)Πu→B(3)Πg, 0-2) with the measured one.