120 research outputs found
Quantum sensors for dynamical tracking of chemical processes
Quantum photonics has demonstrated its potential for enhanced sensing.
Current sources of quantum light states tailored to measuring, allow to monitor
phenomena evolving on time scales of the order of the second. These are
characteristic of product accumulation in chemical reactions of technologically
interest, in particular those involving chiral compounds. Here we adopt a
quantum multiparameter approach to investigate the dynamic process of sucrose
acid hydrolysis as a test bed for such applications. The estimation is made
robust by monitoring different parameters at once
Sleep-Disordered Breathing in Children with Recurrent Wheeze/Asthma: A Single Centre Study
The relationship between asthma and sleep-disordered breathing is bidirectional due to common risk factors that promote airway inflammation. Obstructive sleep-disordered breathing and recurrent wheeze/asthma are conditions that involve the upper and the lower respiratory system, respectively. The aim of the present study was to investigate the sleep disordered breathing in children with recurrent wheeze/asthma. This was a retrospective study concerning children older than 2 years who underwentbetween January 2014 and November 2016an in-laboratory overnight polygraphic study. We match the children between those who do or do not have recurrent wheeze/asthma disease. We examined the clinical records of 137 children. We excluded eight patients because of neurological and genetic conditions. Children with recurrent wheeze/asthma (N = 28) were younger (p = 0.002) and leaner (p = 0.013) compared to non-affected children (N = 98). Children with wheeze/asthma and unaffected ones had a similar obstructive apnea-hypopnea index (p = 0.733) and oxygen desaturation index (p = 0.535). The logistic regression analysis, in which the condition of wheeze/asthma (yes/no) was a dependent variable, while demographic (age, sex, body mass index (BMI) Z-score) and polygraphic results during sleep (obstructive apnea-hypopnea index, central apnea index, peripheral oxygen saturation (SpO(2)), and snoring) were covariates, showed that children with wheeze/asthma had higher central apnea index (Exp(B) = 2.212; Wald 6.845; p = 0.009). In conclusion, children with recurrent wheeze/asthma showed an increased number of central sleep apneas than unaffected children. This finding may suggest a dysfunction of the breathing control in the central nervous system during sleep. Systemic or central inflammation could be the cause
Seizures-like symptoms in an African child with life-threatening severe upper respiratory tract obstruction
Obstructive sleep apneas are characterized by episodes of complete or partial upper airway obstruction during sleep. Symptoms and signs are associated with sleep-related breathing disorders. Sometimes it can be clinically difficult to distinguish abnormal events related to sleep disorders from seizures. We report herein the case of a child with seizures-like symptoms during sleep.Epilepsy was excluded and symptomatology was referred to life-threatening upper respiratory obstruction from tonsils and adenoids hypertrophy that required persistent intubation before surgical removal
Chiari 1 Malformation in a Child with Febrile Seizures, Parasomnias, and Sleep Apnea Syndrome
Introduction. The type I is the most common Chiari malformation in children. In this condition, the lower part of the cerebellum, but not the brain stem, extends into the foramen magnum at the base of the skull leading to disturbances in cerebrospinal fluid circulation and to direct compression of nervous tissue. Case report. We describe a 4-year-old Caucasian female child with febrile seizures, headache, parasomnias, and a delay of speech. The child underwent a magnetic resonance imaging to investigate these neurological signs, disclosing a Chiari malformation type 1. The polysomnography showed a mild-moderate sleep-disordered breathing, increased number of central sleep apneas, and generalized spike waves at sleep onset. Conclusions. Seizures have been seldom described in CM1 patients. The main reasons for performing MRI in this case were frequent seizures, a delay of speech, and headache, leading to an unexpected diagnosis of CM1. Polysomnography detected a discrete SDB
Chiari 1 malformation in a child with febrile seizures, parasomnias, and sleep apnea syndrome
Introduction: The type I is the most common Chiari malformation in children. In this condition, the lower part of the cerebellum, but not the brain stem, extends into the foramen magnum at the base of the skull leading to disturbances in cerebrospinal fluid circulation and to direct compression of nervous tissue. Case report: We describe a 4-year-old Caucasian female child with febrile seizures, headache, parasomnias, and a delay of speech. The child underwent a magnetic resonance imaging to investigate these neurological signs, disclosing a Chiari malformation type 1. The polysomnography showed a mild-moderate sleep-disordered breathing, increased number of central sleep apneas, and generalized spike waves at sleep onset. Conclusions: Seizures have been seldom described in CM1 patients. The main reasons for performing MRI in this case were frequent seizures, a delay of speech, and headache, leading to an unexpected diagnosis of CM1. Polysomnography detected a discrete SDB
Relationship between plasma homocysteine and obstructive sleep apneas in children: a preliminary study
Introduction: Plasma homocysteine concentration is increased adult patients with obstructive sleep apneas, whilst it is still unknown if its plasma levels may also be enhanced in obstructive sleep apnea in childhood. We investigated the possible relationship between plasma homocysteine and obstructive sleep apnea in children. Methods: A total number of 199 children were studied between July 2016 and June 2017. All children underwent an overnight respiratory polygraph study. Laboratory data were retrospectively reviewed, inclusing plasma homocysteine, folate and vitamin B12. Statistical analysis was performed using SPSS Statistics 22.0\uae software. Results: Twenty children were finally included in our study. Linear regression analysis showed that plasma homocysteine was positively correlated with age (\u3b2=2.930; p=0.010), and inversely correlated with folate (\u3b2=-4.830; p<0.001), vitamin B12 (\u3b2=-3.844; p=0.002) and haemoglobin (\u3b2=-3.503; p=0.003). No significant correlation was found with platelet count (p=0.578) and apnea-hypopnea index (p=0.272). After age adjustment, homocysteine levels remained inversely correlated with folate, but no association was found with sleep respiratory parameters. Conclusion: This retrospective study suggests that serum homocysteine levels is not increased in children with obstructive sleep apnea, whilst, a folate-enriched diet seems advisable in children with obstructive sleep apnea to counteract oxidative stress. Further controlled studies are needed
Childhood nasal obstruction and sleep-disordered breathing during clinical setting: Myth or reality?
Objectives. The severity of sleep apneas largely depends on abnormal size of upper airway. Therefore, nasal examination is essential part of clinical evaluation of children with sleep-disordered breathing. Methods. We performed a retrospective survey involving children aged 4 years and older which underwent in-laboratory overnight cardiorespiratory polygraph study between January 2016 and May 2017. Nasal obstruction test was used to score severity. Results. Fifty-three children (62% males) with a median age of 6.1 (IQR 3.1) years were enrolled in this study. Linear regression analysis showed that nasal obstruction score was correlated with apnea-hypopnea index (\u3b2=0.345; p < 0.014) and oxygen desaturation index (\u3b2=0.328; p < 0.022), whilst no association was found with age, BMI z-score, snoring and phase angle. Correlation analysis also showed that nasal obstruction score was correlated with apnea-hypopnea index (r=0.364; p = 0.009) and oxygen desaturation index (r=0.350; p = 0.012) after adjustment for age and BMI z-score., but not with snoring time or phase angle degree. Conclusions. Nasal obstruction test may be a useful, time saving assessment which aid exploring sleep disordered breathing in children. However, this test should not be used alone because it is plagued by objective consideration and at risk of under or overestimation
Snoring in a cohort of obese children: association with palate position and nocturnal desaturations
Purpose of the study: Frequency of habitual snoring is significantly higher in obese than in normal-weight subjects. Obesity and adeno-tonsillar size are risk factors of snoring. Other factors, such as fat distribution and upper airway collapsibility, could explain the relationship between obesity, snoring and obtructive sleep apneas. The aim of the study was to investigate clinical and instrumental significance of snoring in exogenous obese children referred to our department.Methodology: This preliminary study takes part of a larger prospective respiratory sleep study. In 36 consecutive obese children (18 males), bodymass index (BMI), BMI Z score and neck circumference were calculated according to age and sex. Nasal patency, tonsil size, palate position scoring were also recorded. An overnight polygraphy was performed using a portable ambulatory device. Statistical analysis was done using SPSS® Statistics 19.0 software for Windows®.Main findings: Snoring, objectively measured by polygraphy, was associated with palate position and with oxygen desaturation index (ODI). The correlation between snoring and ODI completely disappeared when adjusting for palate position scoring.Key conclusions: Low palate position can be identified as an adjunctive, although not unique, factor that can contribute to making snoring and increased desaturation events possibly related to increased risk of upper airway collapsibility during sleep in obese childre
Thoracoabdominal asynchrony correlates with peripheral vascular resistance changes in a cohort of obese children
Objective: The purpose of this study was to assess the relationship between the thoracoabdominal asynchrony (phase angle), as an index of inspiratory airflow resistance, pulse transit time arousal index (PTT Ar/I), as changes in peripheral vascular resistance and intrathoracic pressure, and obstructive apnea index (OA), Oxygen Desaturation Index (ODI), snoring (% estimated Total Sleep Time - eTST) and apnea-hypopnea index (AHI) in a cohort of exogenous obese children. Material and Methods: Body mass index (BMI) and BMI z-scores were calculated according to age and sex in 36 consecutive obese children. Nasal patency, tonsil size, Friedman palate position scoring were also recorded. An overnight sleep respiratory recording was performed using an polygraphic ambulatory device. Results: Subjects studies had normal to mild sleep respiratory involvement (assessed by respiratory polysomnographic scoring). Phase angle correlated significantly with PTT Ar/I, but not with AHI (n/hr), OA (n/hr), ODI (n/hr) and snoring (% eTST), even adjusting for nasal patency, tonsil hypertrophy, palate position and BMI (z-score). Conclusion: Thoracoabdominal asynchrony (phase angle) is correlated with peripheral vascular resistance changes (PTT Ar/I), suggesting a subclinical upper respiratory airflow anomaly with autonomic activation in obese subjects
A straightforward multiparametric quality control protocol for proton magnetic resonance spectroscopy: Validation and comparison of various 1.5 T and 3 T clinical scanner systems
Purpose: The aim of this study was to propose and validate across various clinical scanner systems a straightforward multiparametric quality assurance procedure for proton magnetic resonance spectroscopy (MRS). Methods: Eighteen clinical 1.5 T and 3 T scanner systems for MRS, from 16 centres and 3 different manufacturers, were enrolled in the study. A standard spherical water phantom was employed by all centres. The acquisition protocol included 3 sets of single (isotropic) voxel (size 20 mm) PRESS acquisitions with unsuppressed water signal and acquisition voxel position at isocenter as well as off-center, repeated 4/5 times within approximately 2 months. Water peak linewidth (LW) and area under the water peak (AP) were estimated. Results: LW values [mean (standard deviation)] were 1.4 (1.0) Hz and 0.8 (0.3) Hz for 3 T and 1.5 T scanners, respectively. The mean (standard deviation) (across all scanners) coefficient of variation of LW and AP for different spatial positions of acquisition voxel were 43% (20%) and 11% (11%), respectively. The mean (standard deviation) phantom T2 values were 1145 (50) ms and 1010 (95) ms for 1.5 T and 3 T scanners, respectively. The mean (standard deviation) (across all scanners) coefficients of variation for repeated measurements of LW, AP and T2 were 25% (20%), 10% (14%) and 5% (2%), respectively. Conclusions: We proposed a straightforward multiparametric and not time consuming quality control protocol for MRS, which can be included in routine and periodic quality assurance procedures. The protocol has been validated and proven to be feasible in a multicentre comparison study of a fairly large number of clinical 1.5 T and 3 T scanner systems
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