K. Chardon - Academia.edu (original) (raw)
Papers by K. Chardon
Additional file 1 Table S1. ICP-MS analysis of Ti content in foetal exudate collected during cont... more Additional file 1 Table S1. ICP-MS analysis of Ti content in foetal exudate collected during control or E171 perfusion. Ti content of foetal exudates from 6 independent E171 perfusion experiments (15 μg/mL) and 1 control perfusion. Samples were collected by time fraction of 10- or (*)15-min during perfusion (first 30 min of 1 h for E5 and E6, total 60 min for E1, E2, E3, E4, and E7). All concentrations are corrected for total blank signals. LOD = 0.23 ng/mL. Typical relative measurement uncertainty was 5% (k = 1). Fig. S1. Basal particulate content in term human placenta. (A and B) Representative TEM-Bright Field micrographs showing particulate matter in the placental tissues. Elemental characterization was determined by TEM-EDX analysis. In addition to Carbon and Oxygen, the following elements were found: ①: Tin, Iron, Silicon; ②:Silicon; ③: Tin, Zinc, Iron, Manganese, Phosphorus, Silicon; ④: Silicon; ⑤: Iron, Aluminium, Silicon; ⑥: Silicon, Aluminium; ⑦: Silicon, Aluminium. (C) ED...
B98. CONTROL OF VENTILATION: WAKEFULNESS TO SLEEP, ANIMALS TO HUMANS, 2009
Autonomic Neuroscience, 2015
Prenatally smoke-exposed neonates have low vagal and elevated sympathetic activities during sleep... more Prenatally smoke-exposed neonates have low vagal and elevated sympathetic activities during sleep. Maternal smoking during pregnancy disrupts heart rate control dynamics in the neonate. The observed effects can be attributed to exclusively prenatal smoking exposure. 3 a b s t r a c t Objective: We aimed to determine whether in utero exposure to smoking may influence the activity and dynamics of cardiac autonomic control in preterm infants. We hypothesized that cardiac autonomic control is altered in preterm infants exposed prenatally to smoking and that these effects may vary as a function of the sleep state. Methods: We studied healthy, preterm neonates born to mothers who had smoked throughout pregnancy but not since birth (n = 16). In utero-exposed neonates were matched with control preterm neonates born to non-smoking mothers (n = 18). Cardiac autonomic control was monitored as a function of the sleep state by assessing heart rate variability with both linear and non-linear methods. Results: Preterm neonates with in utero exposure to smoking displayed alterations (relative to control neonates) in short-term cardiac autonomic control in all sleep states. These alterations included low vagal activity, elevated sympathetic activity, and low complexity and adaptability in heart rate control dynamics. Conclusions: Our results constitute direct evidence that cardiac autonomic activity and control are altered in sleeping preterm infants exposed to smoking in utero. Significance: These alterations may place the affected infants at a higher risk of neurological and cardiovascular complications, which could conceivably persist throughout childhood and adulthood.
Therapeutic Drug Monitoring, 2011
Maternal smoking during pregnancy is associated with adverse perinatal outcomes. In view of conce... more Maternal smoking during pregnancy is associated with adverse perinatal outcomes. In view of concerns about underreporting, benzo[a]pyrene (B[a]P)-DNA adducts could be used to provide information about long-term in utero exposure to smoking but have not previously been used with samples from neonates. This study aimed to verify whether B[a]P-DNA adducts could accurately assess tobacco smoke exposure during fetal life. The objectives were to correlate B[a]P-DNA adduct levels with active maternal and passive smoking and to determine the sensitivity and specificity of smoking and nonsmoking status by comparing neonatal B[a]P-DNA adduct levels with those of maternal self-reports. B[a]P-DNA adducts in neonatal buccal cell samples were determined by a competitive immunoassay. Three groups of neonates were constituted according to maternal self-reported smoking status during pregnancy: nonsmokers (n=25; control group), <10 cigarettes per day (n=18; S- group), or >10 cigarettes per day (n=21; S+ group). The mean B[a]P-DNA adduct level rose significantly when comparing the controls with the S- and S+ groups. Maternal active smoking had the strongest effect on B[a]P-DNA adduct levels in neonates. A cross analysis between B[a]P-DNA adduct levels and maternal self-reported levels revealed high sensitivity and specificity. This preliminary study suggests that B[a]P-DNA adducts are reliable biomarkers for the screening of long-term in utero exposure to smoking and are accurate when compared with maternal self-reported levels of active smoking. Detection of B[a]P-DNA adducts in neonates could provide a useful, noninvasive tool in clinical risk assessment studies but would benefit from further confirmation with another validated biomarker.
Médecine du Sommeil, 2010
ABSTRACT This paper reviews the close relationship between thermoregulation and sleep in neonates... more ABSTRACT This paper reviews the close relationship between thermoregulation and sleep in neonates considering various aspects: (1) thermoregulatory responses differ between sleep stages. In contrast to human or animal adults whose thermoregulation is impaired or abolished, respectively, during REM sleep, in neonates thermoregulation is at least as efficient in active sleep as in quiet sleep; (2) body temperature and sleep–wake cycle rhythms are closely related; (3) manipulation of thermal parameters can influence sleep quantity and structure. In neonates, active sleep is increased by cold challenge, whereas quiet sleep is generally decreased. Sleep duration is reduced as resulting from earlier final awakening.
Skip to Main Content. ...
Sleep and Biological Rhythms, 2007
An estimated 95% of native habitat in the Lower Rio Grande Valley of Texas has been cleared for a... more An estimated 95% of native habitat in the Lower Rio Grande Valley of Texas has been cleared for agriculture and development, threatening a subset of tropical bird species at their northern range limits. Understanding the effects of increasing amounts of urbanization on these native forest birds is important to inform conservation efforts in this biologically diverse region. We evaluated the retention of native forest species in response to local and landscape habitat variables (percent tree cover, amount of dense habitat remaining, and proximity to water). 55 point-count stations were established in residential habitats and remnant urban woodlands, with each point surveyed three times between April and June in 2015. 19 bird species were chosen to represent native forest birds, with presence/absence used to calculate species retention at study points. Local tree cover and amount of dense habitat remaining both had significant positive effects on number of forest birds retained. These results corroborate findings in similar studies, indicating that preservation of remnant urban woodlands is important on a landscape scale to support native forest bird species, and that increased tree cover on a local scale (such as yards and neighborhood) is a viable method to increase habitat for such species.
Particle and Fibre Toxicology, 2020
Background Titanium dioxide (TiO2) is broadly used in common consumer goods, including as a food ... more Background Titanium dioxide (TiO2) is broadly used in common consumer goods, including as a food additive (E171 in Europe) for colouring and opacifying properties. The E171 additive contains TiO2 nanoparticles (NPs), part of them being absorbed in the intestine and accumulated in several systemic organs. Exposure to TiO2-NPs in rodents during pregnancy resulted in alteration of placental functions and a materno-foetal transfer of NPs, both with toxic effects on the foetus. However, no human data are available for pregnant women exposed to food-grade TiO2-NPs and their potential transfer to the foetus. In this study, human placentae collected at term from normal pregnancies and meconium (the first stool of newborns) from unpaired mothers/children were analysed using inductively coupled plasma mass spectrometry (ICP-MS) and scanning transmission electron microscopy (STEM) coupled to energy-dispersive X-ray (EDX) spectroscopy for their titanium (Ti) contents and for analysis of TiO2 pa...
Sleep, 2008
Background: In utero exposure to smoking is known to adversely affect brain regions involved in b... more Background: In utero exposure to smoking is known to adversely affect brain regions involved in behavioral state organization and could therefore interact with the neurophysiological development of neonates. study objectives: The present study investigated the effects of prenatal smoking exposure on sleep patterns in the preterm neonate. Design: Overnight sleep patterns were polysomnographically assessed at thermoneutrality. Sleep continuity and structure were scored for the respective frequencies, durations and percentages of active, quiet, and indeterminate sleep and wakefulness after sleep onset. The number and duration of body movements were also analyzed. setting: The neonatal intensive care unit at Amiens University Medical Center (France). participants: Healthy preterm neonates (postconceptional age: 33.9 ± 6.0 weeks) were enrolled according to whether their mothers had not smoked at all during pregnancy (control group, n = 19), smoked less during pregnancy (low-smoking group, S low , n = 10), or smoked more (heavy-smoking group, S heavy , n = 10) than 10 cigarettes per day throughout pregnancy.
Sleep, 2008
Background: The incidence of apnea in neonates depends on a number of factors, including sleep st... more Background: The incidence of apnea in neonates depends on a number of factors, including sleep state and thermoregulation. objective: To assess the role of thermal drive (body heat loss [BHL]) in the mechanisms underlying short episodes of central apnea during active and quiet sleep in neonates. material and method: Twenty-two neonates (postconceptional age: 36.3 ± 0.9 weeks) were exposed at thermoneutral (incubator temperature: 32.5°C), warm (34.2°C), and cool (30.4°C) conditions during 3 consecutive morning naps. Oxygen consumption (O 2), skin and rectal temperatures, and central apnea were scored during active sleep and quiet sleep. The thermal drive was expressed as BHL calculated using indirect partitional calorimetry. results: As expected, apnea occurred more frequently in active sleep than in quiet sleep (P < 0.001). The frequency of apnea in active sleep was higher in the warm condition (P < 0.05). In contrast, apnea episodes were less frequent (P < 0.05) and shorter (P < 0.05) for cool exposure, during which O 2 and rectal temperature increased. The frequency (P < 0.001, r² = 0.31), mean (P < 0.05, r²=0.06), and maximum (P < 0.001, r² = 0.19) durations of apnea were correlated with the BHL: the greater the BHL (body cooling), the less frequent and the shorter the apnea episodes. In contrast, no relationship between apnea and mean skin or rectal temperature was observed. Conclusion: Apneic events were more closely related to BHL than to body temperatures. In cool exposure, the decreases in the duration and frequency of apneic episodes suggest that these events depend on the metabolic drive (which is proportional to energy expenditure).
A49. SLEEP AND CONTROL OF BREATHING, 2009
Archives de Pédiatrie, 2014
Revue de médecine périnatale, 2014
ABSTRACT Objectif L’étude MecoExpo menée en Picardie, région agricole utilisatrice de pesticides,... more ABSTRACT Objectif L’étude MecoExpo menée en Picardie, région agricole utilisatrice de pesticides, visait à mettre en relation l’exposition parentale et l’imprégnation foetale aux pesticides avec les paramètres cliniques du développement fœtal relevés à la naissance. Matériel et méthode L’exposition parentale aux pesticides a été évaluée par un questionnaire et l’imprégnation foetale aux pesticides, pour la première fois en France, par un dosage dans le méconium. Résultats Neuf cent quatre-vingt-treize couples mère-enfant ont été inclus. Une association entre exposition professionnelle maternelle aux pesticides et augmentation du risque de restriction de croissance fœtale pour le poids de naissance a été observée. Une augmentation du risque de prématurité chez les enfants issus de père travaillant dans un secteur exposé aux pesticides a également été relevée. Quatre-vingt-cinq pour cent des nouveau-nés présentaient au moins un des pesticides recherchés dans leur méconium. Les pesticides observés le plus fréquemment sont les métabolites des organophosphorés et ceux des carbamates, deux grandes familles d’insecticides dispersés sur les grandes cultures. Conclusion Des associations entre l’exposition professionnelle maternelle et paternelle et les paramètres cliniques à la naissance ont été observées. La recherche des pesticides a été réalisée pour la première fois en France dans le méconium de nouveau-nés.
A49. SLEEP AND CONTROL OF BREATHING, 2009
PLoS ONE, 2014
The MecoExpo study was performed in the Picardy region of northern France, in order to investigat... more The MecoExpo study was performed in the Picardy region of northern France, in order to investigate the putative relationship between parental exposures to pesticides (as reported by the mother) on one hand and neonatal parameters on the other. The cohort comprised 993 mother-newborn pairs. Each mother completed a questionnaire that probed occupational, domestic, environmental and dietary sources of parental exposure to pesticides during her pregnancy. Multivariate regression analyses were then used to test for associations between the characteristics of parental pesticide exposure during pregnancy and the corresponding birth outcomes. Maternal occupational exposure was associated with an elevated risk of low birth weight (odds ratio (OR) [95% confidence interval]: 4.2 [1.2, 15.4]). Paternal occupational exposure to pesticides was associated with a lower than average gestational age at birth (20.7 weeks; p = 0.0002) and an elevated risk of prematurity (OR: 3.7 [1.4, 9.7]). Levels of domestic exposure to veterinary antiparasitics and to pesticides for indoor plants were both associated with a low birth weight (270 g; p = 0.02 and 2160 g; p = 0.005, respectively). Babies born to women living in urban areas had a lower birth length and a higher risk of low birth length (20.4 cm, p = 0.006 and OR: 2.9 [1.5, 5.5], respectively). The present study results mainly demonstrate a negative correlation between fetal development on one hand and parental occupational and domestic exposure to pesticides on the other. Our study highlights the need to perform a global and detailed screening of all potential physiological effects when assessing in utero exposure to pesticides.
Handbook of Clinical Neurology, 2011
ABSTRACT This chapter reviews the thermoregulation–sleep interactions in humans. The chapter cons... more ABSTRACT This chapter reviews the thermoregulation–sleep interactions in humans. The chapter considers the various aspects: (1) how thermoregulatory responses can be modified by sleep stages; (2) how skin and internal body temperatures vary according to the sleep–wake cycle; and (3) how manipulation of thermal parameters can influence sleep quantity and structure. The chapter reveals some studies that demonstrate that alterations in one rhythm do not systematically modify the other. This has been found with sleep deprivation, bright light stimulation, and melatonin administration, amongst others. The hypothesis is that, in normal conditions, temperature rhythms are under the control of the circadian clock and act on the sleep–wake cycle by reinforcing circadian control. Sleep onset is facilitated during the declining phase of core temperature. This is mainly obtained by increasing heat loss through peripheral vasodilation. Conversely, it is difficult to maintain sleep when the core temperature is rising. From a practical point of view, it demonstrates that sleep cannot be scheduled no matter when—it needs to be prepared, as suggested by the discrete thermoregulatory changes observed prior to sleep. Having a regular bedtime makes it more likely that sleep onset will occur during the decreasing phase of core body temperature.
Surgical and Radiologic Anatomy, 2007
The biometry and the histology of coronary, radial, ulnar, epigastric and internal thoracic arter... more The biometry and the histology of coronary, radial, ulnar, epigastric and internal thoracic arteries were studied in order to investigate the cause of their occlusions in coronary bypass grafts and to improve the results of these bypass grafts. These various arteries were removed from 40 anatomical specimens (27 males and 13 females). We found a correlation between the internal calibers of the ulnar and coronary arteries in males. Intimal changes and the presence of atheromatous plaque were observed in coronary, radial and ulnar arteries, but never in the internal thoracic artery. Like coronary arteries and their branches, radial, ulnar and epigastric arteries are muscular arteries and ageing results in thickening of the intima, which becomes Wbrotic with migration of myocytes from the media and duplication of the internal elastic lamina. The media becomes Wbrous, hypertrophic or atrophic. In contrast, the internal thoracic artery is an elastic artery, like the aorta. Ageing is characterized by loss, over a variable extent, of one or several elastic laminae of the media and more marked intimal thickening. Although anatomically, the caliber of radial, ulnar, and epigastric arteries remains adapted to that of coronary arteries, the long-term patency of radial, ulnar and epigastric arteries used as grafts is related to their histological characteristics.
Additional file 1 Table S1. ICP-MS analysis of Ti content in foetal exudate collected during cont... more Additional file 1 Table S1. ICP-MS analysis of Ti content in foetal exudate collected during control or E171 perfusion. Ti content of foetal exudates from 6 independent E171 perfusion experiments (15 μg/mL) and 1 control perfusion. Samples were collected by time fraction of 10- or (*)15-min during perfusion (first 30 min of 1 h for E5 and E6, total 60 min for E1, E2, E3, E4, and E7). All concentrations are corrected for total blank signals. LOD = 0.23 ng/mL. Typical relative measurement uncertainty was 5% (k = 1). Fig. S1. Basal particulate content in term human placenta. (A and B) Representative TEM-Bright Field micrographs showing particulate matter in the placental tissues. Elemental characterization was determined by TEM-EDX analysis. In addition to Carbon and Oxygen, the following elements were found: ①: Tin, Iron, Silicon; ②:Silicon; ③: Tin, Zinc, Iron, Manganese, Phosphorus, Silicon; ④: Silicon; ⑤: Iron, Aluminium, Silicon; ⑥: Silicon, Aluminium; ⑦: Silicon, Aluminium. (C) ED...
B98. CONTROL OF VENTILATION: WAKEFULNESS TO SLEEP, ANIMALS TO HUMANS, 2009
Autonomic Neuroscience, 2015
Prenatally smoke-exposed neonates have low vagal and elevated sympathetic activities during sleep... more Prenatally smoke-exposed neonates have low vagal and elevated sympathetic activities during sleep. Maternal smoking during pregnancy disrupts heart rate control dynamics in the neonate. The observed effects can be attributed to exclusively prenatal smoking exposure. 3 a b s t r a c t Objective: We aimed to determine whether in utero exposure to smoking may influence the activity and dynamics of cardiac autonomic control in preterm infants. We hypothesized that cardiac autonomic control is altered in preterm infants exposed prenatally to smoking and that these effects may vary as a function of the sleep state. Methods: We studied healthy, preterm neonates born to mothers who had smoked throughout pregnancy but not since birth (n = 16). In utero-exposed neonates were matched with control preterm neonates born to non-smoking mothers (n = 18). Cardiac autonomic control was monitored as a function of the sleep state by assessing heart rate variability with both linear and non-linear methods. Results: Preterm neonates with in utero exposure to smoking displayed alterations (relative to control neonates) in short-term cardiac autonomic control in all sleep states. These alterations included low vagal activity, elevated sympathetic activity, and low complexity and adaptability in heart rate control dynamics. Conclusions: Our results constitute direct evidence that cardiac autonomic activity and control are altered in sleeping preterm infants exposed to smoking in utero. Significance: These alterations may place the affected infants at a higher risk of neurological and cardiovascular complications, which could conceivably persist throughout childhood and adulthood.
Therapeutic Drug Monitoring, 2011
Maternal smoking during pregnancy is associated with adverse perinatal outcomes. In view of conce... more Maternal smoking during pregnancy is associated with adverse perinatal outcomes. In view of concerns about underreporting, benzo[a]pyrene (B[a]P)-DNA adducts could be used to provide information about long-term in utero exposure to smoking but have not previously been used with samples from neonates. This study aimed to verify whether B[a]P-DNA adducts could accurately assess tobacco smoke exposure during fetal life. The objectives were to correlate B[a]P-DNA adduct levels with active maternal and passive smoking and to determine the sensitivity and specificity of smoking and nonsmoking status by comparing neonatal B[a]P-DNA adduct levels with those of maternal self-reports. B[a]P-DNA adducts in neonatal buccal cell samples were determined by a competitive immunoassay. Three groups of neonates were constituted according to maternal self-reported smoking status during pregnancy: nonsmokers (n=25; control group), &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;10 cigarettes per day (n=18; S- group), or &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;10 cigarettes per day (n=21; S+ group). The mean B[a]P-DNA adduct level rose significantly when comparing the controls with the S- and S+ groups. Maternal active smoking had the strongest effect on B[a]P-DNA adduct levels in neonates. A cross analysis between B[a]P-DNA adduct levels and maternal self-reported levels revealed high sensitivity and specificity. This preliminary study suggests that B[a]P-DNA adducts are reliable biomarkers for the screening of long-term in utero exposure to smoking and are accurate when compared with maternal self-reported levels of active smoking. Detection of B[a]P-DNA adducts in neonates could provide a useful, noninvasive tool in clinical risk assessment studies but would benefit from further confirmation with another validated biomarker.
Médecine du Sommeil, 2010
ABSTRACT This paper reviews the close relationship between thermoregulation and sleep in neonates... more ABSTRACT This paper reviews the close relationship between thermoregulation and sleep in neonates considering various aspects: (1) thermoregulatory responses differ between sleep stages. In contrast to human or animal adults whose thermoregulation is impaired or abolished, respectively, during REM sleep, in neonates thermoregulation is at least as efficient in active sleep as in quiet sleep; (2) body temperature and sleep–wake cycle rhythms are closely related; (3) manipulation of thermal parameters can influence sleep quantity and structure. In neonates, active sleep is increased by cold challenge, whereas quiet sleep is generally decreased. Sleep duration is reduced as resulting from earlier final awakening.
Skip to Main Content. ...
Sleep and Biological Rhythms, 2007
An estimated 95% of native habitat in the Lower Rio Grande Valley of Texas has been cleared for a... more An estimated 95% of native habitat in the Lower Rio Grande Valley of Texas has been cleared for agriculture and development, threatening a subset of tropical bird species at their northern range limits. Understanding the effects of increasing amounts of urbanization on these native forest birds is important to inform conservation efforts in this biologically diverse region. We evaluated the retention of native forest species in response to local and landscape habitat variables (percent tree cover, amount of dense habitat remaining, and proximity to water). 55 point-count stations were established in residential habitats and remnant urban woodlands, with each point surveyed three times between April and June in 2015. 19 bird species were chosen to represent native forest birds, with presence/absence used to calculate species retention at study points. Local tree cover and amount of dense habitat remaining both had significant positive effects on number of forest birds retained. These results corroborate findings in similar studies, indicating that preservation of remnant urban woodlands is important on a landscape scale to support native forest bird species, and that increased tree cover on a local scale (such as yards and neighborhood) is a viable method to increase habitat for such species.
Particle and Fibre Toxicology, 2020
Background Titanium dioxide (TiO2) is broadly used in common consumer goods, including as a food ... more Background Titanium dioxide (TiO2) is broadly used in common consumer goods, including as a food additive (E171 in Europe) for colouring and opacifying properties. The E171 additive contains TiO2 nanoparticles (NPs), part of them being absorbed in the intestine and accumulated in several systemic organs. Exposure to TiO2-NPs in rodents during pregnancy resulted in alteration of placental functions and a materno-foetal transfer of NPs, both with toxic effects on the foetus. However, no human data are available for pregnant women exposed to food-grade TiO2-NPs and their potential transfer to the foetus. In this study, human placentae collected at term from normal pregnancies and meconium (the first stool of newborns) from unpaired mothers/children were analysed using inductively coupled plasma mass spectrometry (ICP-MS) and scanning transmission electron microscopy (STEM) coupled to energy-dispersive X-ray (EDX) spectroscopy for their titanium (Ti) contents and for analysis of TiO2 pa...
Sleep, 2008
Background: In utero exposure to smoking is known to adversely affect brain regions involved in b... more Background: In utero exposure to smoking is known to adversely affect brain regions involved in behavioral state organization and could therefore interact with the neurophysiological development of neonates. study objectives: The present study investigated the effects of prenatal smoking exposure on sleep patterns in the preterm neonate. Design: Overnight sleep patterns were polysomnographically assessed at thermoneutrality. Sleep continuity and structure were scored for the respective frequencies, durations and percentages of active, quiet, and indeterminate sleep and wakefulness after sleep onset. The number and duration of body movements were also analyzed. setting: The neonatal intensive care unit at Amiens University Medical Center (France). participants: Healthy preterm neonates (postconceptional age: 33.9 ± 6.0 weeks) were enrolled according to whether their mothers had not smoked at all during pregnancy (control group, n = 19), smoked less during pregnancy (low-smoking group, S low , n = 10), or smoked more (heavy-smoking group, S heavy , n = 10) than 10 cigarettes per day throughout pregnancy.
Sleep, 2008
Background: The incidence of apnea in neonates depends on a number of factors, including sleep st... more Background: The incidence of apnea in neonates depends on a number of factors, including sleep state and thermoregulation. objective: To assess the role of thermal drive (body heat loss [BHL]) in the mechanisms underlying short episodes of central apnea during active and quiet sleep in neonates. material and method: Twenty-two neonates (postconceptional age: 36.3 ± 0.9 weeks) were exposed at thermoneutral (incubator temperature: 32.5°C), warm (34.2°C), and cool (30.4°C) conditions during 3 consecutive morning naps. Oxygen consumption (O 2), skin and rectal temperatures, and central apnea were scored during active sleep and quiet sleep. The thermal drive was expressed as BHL calculated using indirect partitional calorimetry. results: As expected, apnea occurred more frequently in active sleep than in quiet sleep (P < 0.001). The frequency of apnea in active sleep was higher in the warm condition (P < 0.05). In contrast, apnea episodes were less frequent (P < 0.05) and shorter (P < 0.05) for cool exposure, during which O 2 and rectal temperature increased. The frequency (P < 0.001, r² = 0.31), mean (P < 0.05, r²=0.06), and maximum (P < 0.001, r² = 0.19) durations of apnea were correlated with the BHL: the greater the BHL (body cooling), the less frequent and the shorter the apnea episodes. In contrast, no relationship between apnea and mean skin or rectal temperature was observed. Conclusion: Apneic events were more closely related to BHL than to body temperatures. In cool exposure, the decreases in the duration and frequency of apneic episodes suggest that these events depend on the metabolic drive (which is proportional to energy expenditure).
A49. SLEEP AND CONTROL OF BREATHING, 2009
Archives de Pédiatrie, 2014
Revue de médecine périnatale, 2014
ABSTRACT Objectif L’étude MecoExpo menée en Picardie, région agricole utilisatrice de pesticides,... more ABSTRACT Objectif L’étude MecoExpo menée en Picardie, région agricole utilisatrice de pesticides, visait à mettre en relation l’exposition parentale et l’imprégnation foetale aux pesticides avec les paramètres cliniques du développement fœtal relevés à la naissance. Matériel et méthode L’exposition parentale aux pesticides a été évaluée par un questionnaire et l’imprégnation foetale aux pesticides, pour la première fois en France, par un dosage dans le méconium. Résultats Neuf cent quatre-vingt-treize couples mère-enfant ont été inclus. Une association entre exposition professionnelle maternelle aux pesticides et augmentation du risque de restriction de croissance fœtale pour le poids de naissance a été observée. Une augmentation du risque de prématurité chez les enfants issus de père travaillant dans un secteur exposé aux pesticides a également été relevée. Quatre-vingt-cinq pour cent des nouveau-nés présentaient au moins un des pesticides recherchés dans leur méconium. Les pesticides observés le plus fréquemment sont les métabolites des organophosphorés et ceux des carbamates, deux grandes familles d’insecticides dispersés sur les grandes cultures. Conclusion Des associations entre l’exposition professionnelle maternelle et paternelle et les paramètres cliniques à la naissance ont été observées. La recherche des pesticides a été réalisée pour la première fois en France dans le méconium de nouveau-nés.
A49. SLEEP AND CONTROL OF BREATHING, 2009
PLoS ONE, 2014
The MecoExpo study was performed in the Picardy region of northern France, in order to investigat... more The MecoExpo study was performed in the Picardy region of northern France, in order to investigate the putative relationship between parental exposures to pesticides (as reported by the mother) on one hand and neonatal parameters on the other. The cohort comprised 993 mother-newborn pairs. Each mother completed a questionnaire that probed occupational, domestic, environmental and dietary sources of parental exposure to pesticides during her pregnancy. Multivariate regression analyses were then used to test for associations between the characteristics of parental pesticide exposure during pregnancy and the corresponding birth outcomes. Maternal occupational exposure was associated with an elevated risk of low birth weight (odds ratio (OR) [95% confidence interval]: 4.2 [1.2, 15.4]). Paternal occupational exposure to pesticides was associated with a lower than average gestational age at birth (20.7 weeks; p = 0.0002) and an elevated risk of prematurity (OR: 3.7 [1.4, 9.7]). Levels of domestic exposure to veterinary antiparasitics and to pesticides for indoor plants were both associated with a low birth weight (270 g; p = 0.02 and 2160 g; p = 0.005, respectively). Babies born to women living in urban areas had a lower birth length and a higher risk of low birth length (20.4 cm, p = 0.006 and OR: 2.9 [1.5, 5.5], respectively). The present study results mainly demonstrate a negative correlation between fetal development on one hand and parental occupational and domestic exposure to pesticides on the other. Our study highlights the need to perform a global and detailed screening of all potential physiological effects when assessing in utero exposure to pesticides.
Handbook of Clinical Neurology, 2011
ABSTRACT This chapter reviews the thermoregulation–sleep interactions in humans. The chapter cons... more ABSTRACT This chapter reviews the thermoregulation–sleep interactions in humans. The chapter considers the various aspects: (1) how thermoregulatory responses can be modified by sleep stages; (2) how skin and internal body temperatures vary according to the sleep–wake cycle; and (3) how manipulation of thermal parameters can influence sleep quantity and structure. The chapter reveals some studies that demonstrate that alterations in one rhythm do not systematically modify the other. This has been found with sleep deprivation, bright light stimulation, and melatonin administration, amongst others. The hypothesis is that, in normal conditions, temperature rhythms are under the control of the circadian clock and act on the sleep–wake cycle by reinforcing circadian control. Sleep onset is facilitated during the declining phase of core temperature. This is mainly obtained by increasing heat loss through peripheral vasodilation. Conversely, it is difficult to maintain sleep when the core temperature is rising. From a practical point of view, it demonstrates that sleep cannot be scheduled no matter when—it needs to be prepared, as suggested by the discrete thermoregulatory changes observed prior to sleep. Having a regular bedtime makes it more likely that sleep onset will occur during the decreasing phase of core body temperature.
Surgical and Radiologic Anatomy, 2007
The biometry and the histology of coronary, radial, ulnar, epigastric and internal thoracic arter... more The biometry and the histology of coronary, radial, ulnar, epigastric and internal thoracic arteries were studied in order to investigate the cause of their occlusions in coronary bypass grafts and to improve the results of these bypass grafts. These various arteries were removed from 40 anatomical specimens (27 males and 13 females). We found a correlation between the internal calibers of the ulnar and coronary arteries in males. Intimal changes and the presence of atheromatous plaque were observed in coronary, radial and ulnar arteries, but never in the internal thoracic artery. Like coronary arteries and their branches, radial, ulnar and epigastric arteries are muscular arteries and ageing results in thickening of the intima, which becomes Wbrotic with migration of myocytes from the media and duplication of the internal elastic lamina. The media becomes Wbrous, hypertrophic or atrophic. In contrast, the internal thoracic artery is an elastic artery, like the aorta. Ageing is characterized by loss, over a variable extent, of one or several elastic laminae of the media and more marked intimal thickening. Although anatomically, the caliber of radial, ulnar, and epigastric arteries remains adapted to that of coronary arteries, the long-term patency of radial, ulnar and epigastric arteries used as grafts is related to their histological characteristics.