Revisiting the maintenance of wakefulness test: from intra-/inter-scorer agreement to normative values in patients treated for obstructive sleep apnea

The Maintenance of Wakefulness Test is widely used to objectively assess sleepiness and make safety-related decisions, but its interpretation is subjective and normative values remain debated. Our work aimed to determine normative thresholds in non-subjectively sleepy patients with well-treated obstructive sleep apnea, and to assess intra- and inter-scorer variability. We included maintenance of wakefulness tests of 141 consecutive patients with treated obstructive sleep apnea (90% men, mean (SD) age 47.5 (9.2) years, mean (SD) pre-treatment apnea-hypopnea index of 43.8 (20.3) events/h). Sleep onset latencies were independently scored by two experts. Discordant scorings were reviewed to reach a consensus and half of the cohort was double-scored by each scorer. Intra- and inter-scorer variability was assessed using Cohen's kappa for 40, 33, and 19 min mean sleep latency thresholds. Consensual mean sleep latencies were compared between four groups according to subjective sleepiness (Epworth Sleepiness Scale score < versus ≥11) and residual apnea-hypopnea index (< versus ≥15 events/h). In well-treated non-sleepy patients (n = 76), the consensual mean (SD) sleep latency was 38.4 (4.2) min (lower normal limit [mean - 2SD] = 30 min), and 80% of them did not fall asleep. Intra-scorer agreement on mean sleep latency was high but inter-scorer was only fair (Cohen's kappa 0.54 for 33-min threshold, 0.27 for 19-min threshold), resulting in changes in latency category in 4%-12% of patients. A higher sleepiness score but not the residual apnea-hypopnea index was significantly associated with a lower mean sleep latency. Our findings suggest a higher than usually accepted normative threshold (30 min) in this context and emphasise the need for more reproducible scoring approaches.

Impaired post-sleep apnea autonomic arousals in patients with drug-resistant epilepsy

OBJECTIVE

Sudden and unexpected deaths in epilepsy (SUDEP) pathophysiology may involve an interaction between respiratory dysfunction and sleep/wake state regulation. We investigated whether patients with epilepsy exhibit impaired sleep apnea-related arousals.

METHODS

Patients with drug-resistant (N = 20) or drug-sensitive (N = 20) epilepsy and obstructive sleep apnea, as well as patients with sleep apnea but without epilepsy (controls, N = 20) were included. We explored (1) the respiratory arousal threshold based on nadir oxygen saturation, apnea-hypopnea index, and fraction of hypopnea among respiratory events; (2) the cardiac autonomic response to apnea/hypopnea quantified as percentages of changes from the baseline in RR intervals (RRI), high (HF) and low (LF) frequency powers, and LF/HF.

RESULTS

The respiratory arousal threshold did not differ between groups. At arousal onset, RRI decreased (-9.42%) and LF power (179%) and LF/HF ratio (190%) increased. This was followed by an increase in HF power (118%), p < 0.05. The RRI decrease was lower in drug-resistant (-7.40%) than in drug-sensitive patients (-9.94%) and controls (-10.91%), p < 0.05. LF and HF power increases were higher in drug-resistant (188%/126%) than in drug-sensitive patients (172%/126%) and controls (177%/115%), p < 0.05.

CONCLUSIONS

Cardiac reactivity following sleep apnea is impaired in drug-resistant epilepsy.

SIGNIFICANCE

This autonomic dysfunction might contribute to SUDEP pathophysiology.

Epidemiology of Bovine Hemorrhagic Bowel Syndrome in Belgium and The Netherlands

Hemorrhagic bowel syndrome (HBS) is a poorly understood, sporadic and often fatal disease in cattle. Although, HBS is considered an important disease in dairy cattle, epidemiological data is largely lacking. This study describes the epidemiology of HBS in Belgium and the Netherlands, based on necropsy records from 2009 to 2022, and reports characteristics from 27 cows and 35 dairy operations with HBS, gathered through a survey. The annual incidence of HBS has a significantly increasing trend both at cow and herd level, with incidence above 3.2% in necropsied mature dairy cattle in the most recent years. Estimated herd-level incidence in the Netherlands was double the estimated incidence in Belgium, which might be explained by higher herd size in the Netherlands. Occurrence of HBS was most prevalent in fall, being 40.1% higher than the average of the other seasons. In 35 Flemish (Belgian) surveyed dairy herds with HBS, manifestation of HBS was mostly as solitary cases, and if multiple cases occurred, the time interval was highly variable. In addition, the majority of cows with HBS (61.1%; 16/26) were in more than 100 days lactation. In conclusion, HBS is an important and possibly emerging disease in dairy cattle in Belgium and the Netherlands.

Unveiled central hypoventilation after tracheotomy in anti-IgLON5 disease: a case report

Anti-IgLON5 disease is a recently described entity that has been associated with neurological symptoms and sleep disturbances including sleep breathing disorders. Sleep stridor as well as obstructive and less often central sleep apnea have been reported but rarely needing ventilation on tracheotomy. We report the case of a patient in whom obstructive sleep apnea with secondary development of dysphagia and recurrent aspiration pneumonia led to the diagnosis of anti-IgLON 5 disease. Acute respiratory failure due to laryngospasm required intubation and eventually tracheotomy. Yet hypoventilation persisted, and polysomnography demonstrated central sleep apnea alternating with sleep-related tachypnea. Nocturnal ventilation was thus reintroduced. The association of obstructive sleep apnea with dysphagia is a potential red flag for anti-IgLON5 disease, which remains an overlooked diagnosis. Breathing disorders can be complex in this context, with a mixed obstructive and central pattern whose central component can be unveiled after tracheotomy. This highlights the importance of closely monitoring sleep and respiration even after tracheotomy.

CITATION

Tankéré P, Le Cam P, Folliet L, et al. Unveiled central hypoventilation after tracheotomy in anti-IgLON5 disease: a case report. J Clin Sleep Med. 2023;19(9):1701-1704.

Grazing Mares on Pasture with Sycamore Maples: A Potential Threat to Suckling Foals and Food Safety through Milk Contamination

Simple Summary

Equine atypical myopathy is seasonal poisoning resulting from the ingestion of seeds and seedlings of the sycamore maple that contains toxins. Literature mentions several cases of intoxication among gravid mares and in unweaned foals. The objective of this study was to determine whether the toxins responsible for atypical myopathy could pass to the foal via suckling. Four mares that were pasturing with sycamore in the vicinity were milked. Analysis revealed the presence of toxins in milk. This unprecedented observation could partially explain cases of unweaned foals suffering from atypical myopathy. However, a transplacental transfer of the toxin cannot be excluded for newborn cases. Besides being a source of contamination for offspring, milk contamination by toxins from fruits of trees of the Sapindaceae family might constitute a potential risk for food safety regarding other species’ raw milk or dairy products.

Abstract

Equine atypical myopathy (AM) is seasonal intoxication resulting from the ingestion of seeds and seedlings of the sycamore maple (Acer pseudoplatanus) that contain toxins, among them, hypoglycin A (HGA). Literature mentions several cases of AM among gravid mares and in unweaned foals. The objective of this study was to determine whether HGA and/or its metabolite are present in milk from grazing mares exposed to sycamore maple trees as confirmed by detection of HGA and its metabolite in their blood. Four mare/foal couples were included in the study. Both HGA and its metabolite were detectable in all but one of the milk samples. To our knowledge, this is the first study describing transfer of HGA to the milk. This unprecedented observation could partially explain cases of unweaned foals suffering from AM. However, a transplacental transfer of the toxin cannot be excluded for newborn foals. Besides being a source of contamination for offspring, milk contamination by toxins from fruits of trees of the Sapindaceae family might constitute a potential risk for food safety regarding other species’ raw milk or dairy products.

Benefit of continuous positive airway pressure on work quality in patients with severe obstructive sleep apnea

BACKGROUND

The objective of this prospective study was to assess the effect of CPAP therapy on job productivity and work quality for patients with severe obstructive sleep apnea (OSA).

METHODS

A convenience sample of patients diagnosed with severe OSA using polysomnography or polygraphy and with a therapeutic indication for CPAP was enrolled in our study. Patients completed two self-administered questionnaires: the first before CPAP therapy and the second during the first 6 months after CPAP treatment. OSA symptoms were evaluated through self-administered questionnaires assessing potential effects on occupational activity: excessive daytime sleepiness was rated by the Epworth Sleepiness Scale (ESS), emotional status was rated by the Hospital Anxiety and Depression (HAD) scale, work quality was rated by the Work Role Functioning Questionnaire (WRFQ).

RESULTS

Forty patients (30 men, mean age 47.3 ± 8.3, mean BMI 31.6 ± 7.4, mean apnea-hypopnea index 51.8 ± 16.3) showed a beneficial effect of CPAP therapy on ESS score (mean 11.6 to 8.2, p < 0.0001), the anxiety dimension (mean 57.5% to 20%, p = 0.0002), and the overall anxiety-depressive score (mean 50% to 22.5%, p = 0.0006). Mean WRFQ scores were significantly improved in the second questionnaire for the dimensions of timetable requirements (69.3% to 83.5%, p < 0.0001), productivity requirements (71.4% to 82.2%, p < 0.0001), mental requirements (72.0% to 84.3%, p < 0.0001), and social requirements (82.6% to 91.4%, p < 0.003).

CONCLUSIONS

We observed that adherence to CPAP therapy for patients with severe OSA mitigates the impact of symptoms on work including excessive daytime sleepiness, impairment of work ability, and anxiety and depressive disorders.

Study of the viticultural technical itineraries carbon footprint at fine scale

Viticulture faces two challenges regarding climate change: adapting and mitigating greenhouse gas emissions. Are these two challenges compatible? This is one of the questions to which Adviclim project (Life project, 2014–2019) provided tools and answers. The assessment of greenhouse gas emissions was implemented at the scale of the plot using a life cycle approach: calculating the carbon footprint. This approach makes it possible to take into account the emissions generated during each stage of the life cycle of a product or a service: in this case, the cultivation of one hectare of vine for one year. Carbon footprint was assessed for the 5 pilot sites of the Adviclim project: Saint-Emilion (France), Coteaux du Layon/Samur (France), Geisenheim (Germany), Cotnari (Romania) and Plompton (United Kingdom). An important work for primary data collection regarding observed practices was carried out with a sample of reresentative farms for these 5 sites, and for one to three vintages depending on the site. Beyond the question asked in the project, the calculation of these carbon footprints made it possible to (i) make winegrowers aware of the life cycle approach and the share of direct emissions generated by viticulture, (ii) acquire new references on the technical itineraries and their associated emissions, (iii) improve the adaptation of the methodology for calculating the carbon footprint to viticulture.

Resurgence of Schmallenberg Virus in Belgium after 3 Years of Epidemiological Silence

In spring 2016, three years after the last reported outbreak of Schmallenberg virus (SBV) in Belgium, an abortion was notified in a two year old Holstein heifer that previously had not been vaccinated against SBV. The autopsy of the eight-month-old malformed foetus revealed hydrocephalus, torticollis and arthrogryposis. Foetal brain tissue and blood were found to be SBV-positive by RT-PCR and ELISA tests, respectively. Evidencing the circulation of SBV in Belgium in the autumn 2015 is important to anticipate future outbreaks and advise veterinarians about the risks associated with calving, as more bovine foetuses might have been infected.

Congenital jaundice in bovine aborted foetuses: an emerging syndrome in southern Belgium

Southern Belgium faces an unusual recent increase of icteric bovine aborted foetuses. In the necropsy room, the majority of foetuses presented jaundice and splenomegaly. Despite a wide range of analyses, no definitive cause of abortion has yet been established but some analysis results support the leptospirosis hypothesis. This first description of cases will help veterinary practitioners to recognize more cases and to conduct those to the laboratory for future investigations.

Absence of airway secretion accumulation predicts tolerance of noninvasive ventilation in subjects with amyotrophic lateral sclerosis

OBJECTIVE

To assess factors that predict good tolerance of noninvasive ventilation (NIV), in order to improve survival and quality of life in subjects with amyotrophic lateral sclerosis.

METHODS

We conducted a prospective study in subjects with amyotrophic lateral sclerosis and requiring NIV. The primary end point was NIV tolerance at 1 month. Subjects, several of whom failed to complete the study, were classified as "tolerant" or "poorly tolerant," according to the number of hours of NIV use (more or less than 4 h per night, respectively).

RESULTS

Eighty-one subjects, 73 of whom also attended the 1-month follow-up visit, participated over 34 months. NIV tolerance after the first day of utilization predicted tolerance at 1 month (77.6% and 75.3% of subjects, respectively). Multivariate analysis disclosed 3 factors predicting good NIV tolerance: absence of airway secretions accumulation prior to NIV onset (odds ratio 11.5); normal bulbar function at initiation of NIV (odds ratio 8.5); and older age (weakly significant, odds ratio 1.1).

CONCLUSION

Our study reveals 3 factors that are predictive of good NIV tolerance, in particular the absence of airway secretion accumulation, which should prompt NIV initiation before its appearance.

Motor and respiratory heterogeneity in Duchenne patients: implication for clinical trials

AIMS

Our objective was to clarify the clinical heterogeneity in Duchenne muscular dystrophy (DMD).

METHODS

The French dystrophinopathy database provided clinical, histochemical and molecular data of 278 DMD patients (mean longitudinal follow-up: 14.2 years). Diagnosis was based on mutation identification in the DMD gene. Three groups were defined according to the age at ambulation loss: before 8 years (group A); between 8 and 11 years (group B); between 11 and 16 years (group C).

RESULTS

Motor and respiratory declines were statistically different between the three groups, as opposed to heart involvement. When acquired, running ability was lost at the mean age of 5.41 (group A), 7.11 (group B), 9.19 (group C) years; climbing stairs ability at 6.24 (group A), 7.99 (group B), 10,42 (group C) years, and ambulation at 7.10 (group A), 9.25 (group B), 12.01 (group C) years. Pulmonary growth stopped at 10.26 (group A), 12.45 (group B), 14.58 (group C) years. Then, forced vital capacity decreased at the rate of 8.83 (group A), 7.52 (group B), 6.03 (group C) percent per year. Phenotypic variability did not rely on specific mutational spectrum.

CONCLUSION

Beside the most common form of DMD (group B), we provide detailed description on two extreme clinical subgroups: a severe one (group A) characterized by early severe motor and respiratory decline and a milder subgroup (group C). Compared to group B or C, four to six times fewer patients from group A are needed to detect the same decrease in disease progression in a clinical trial.

The short-term effects of intermittent positive pressure breathing treatments on ventilation in patients with neuromuscular disease

BACKGROUND

The effects of intermittent positive-pressure breathing (IPPB) and abdominal belt on regional lung ventilation in neuromuscular patients are unknown. We conducted a prospective physiologic short-term study in stable neuromuscular patients to determine the effects of IPBB, with and without abdominal belt, on regional lung ventilation.

METHODS

IPPB was performed as 30 consecutive deep breaths up to 30 cm H(2)O face-mask pressure each: 10 in supine position, 10 in left-lateral position, and 10 in right-lateral position. Each patient received IPPB sessions with and without an abdominal belt, in a random order, at one-day intervals. Patients were then followed-up to 3 hours after IPPB. Lung ventilation was measured via electrical-impedance tomography (tidal volume via electrical-impedance tomography [electrical-impedance V(T)], which is reported in arbitrary units) in 4 lung quadrants. Baseline V(T) and exhaled V(T) after each deep breath were also measured. The primary outcome was maintenance of regional ventilation after 3 hours.

RESULTS

Global electrical-impedance V(T) remained significantly higher than at baseline as long as 3 hours after the IPPB sessions. Global and regional electrical-impedance V(T) at the end of the 3-hour study period was significantly higher with the abdominal belt in place. Regional ventilation did not change significantly. With IPPB in the supine position, electrical-impedance V(T) was significantly greater in the anterior than the posterior lung regions (P < .001). With IPPB in supine position, median and interquartile range V(T) values increased from 0.25 L (0.20-0.30) to the exhaled V(T) of 1.50 L (1.08-1.96) (P < .001). There were no differences in regional ventilation.

CONCLUSIONS

In patients with neuromuscular disease, supine IPPB treatments, with or without abdominal belt, increased ventilation to anterior lungs regions, compared to the left-lateral and right-lateral positions. Global ventilation 3 hours after IPPB treatments remained higher than at baseline and was best preserved with the use of an abdominal belt.

Sleep and respiratory function after withdrawal of noninvasive ventilation in patients with chronic respiratory failure

BACKGROUND

In patients with restrictive thoracic disease, little is known about changes in sleep and breathing if the patient stops using nocturnal noninvasive ventilation (NIV). Better understanding of those changes may affect NIV management and improve our understanding of the relationship of night-to-night variability of respiratory and sleep variables and morning gas exchange.

METHODS

With 6 stable patients with restrictive chronic respiratory failure who were being treated with home NIV we conducted a 5-step study: (1) The subject underwent an in-hospital baseline sleep study while on NIV, then next-morning pulmonary function tests. (2) At home, on consecutive nights, the subject underwent the same sleep-study measurements while not using NIV, until the patient had what we defined as respiratory decompensation (oxygen saturation measured via pulse oximetry [S(pO(2))] < 88% or end-tidal CO(2) pressure [P(ETCO(2))] > 50 mm Hg, with or without headaches, fatigue, or worsening dyspnea). Each morning after each home sleep-study night off NIV, we also measured S(pO(2)) and P(ETCO(2)). (3) The patient returned to the hospital for a second overnight assessment, the same as the baseline assessment except without NIV. (4) The patient went home and restarted using NIV with his or her pre-study NIV settings. (5) After the number of nights back on home NIV matched the number of nights the patient had been off NIV, the patient returned to the hospital for a third in-hospital assessment. We measured static lung volumes, maximum inspiratory and expiratory static mouth pressure, breathing pattern, arterial blood gases, S(pO(2)), P(ETCO(2)), and full overnight polysomnography values.

RESULTS

Respiratory decompensation occurred 4-15 days after NIV discontinuation (mean 6.8 d). On the first and second in-hospital assessment nights, respectively, the mean nadir nocturnal S(pO(2)) values were 84 +/- 2% and 64 +/- 4%, the total apnea-hypopnea index values were 0 +/- 0 and 9 +/- 2, and the obstructive hypopnea index values were 0 +/- 0 and 7 +/- 1 episodes per total sleep hour. Respiratory events started on the first night off NIV. Spirometry, muscle strength, and sleep architecture did not change significantly. With resumption of NIV, baseline conditions were recovered.

CONCLUSIONS

NIV discontinuation in patients with restrictive chronic respiratory failure previously stabilized on NIV promptly leads to nocturnal respiratory failure and within days to diurnal respiratory failure. Stopping NIV for more than a day or two is not recommended.

Dilative arteriopathy and basilar artery dolichoectasia complicating late-onset Pompe disease

BACKGROUND

Strokes related to intracranial aneurysm or arteriopathy have been reported in a few patients with late-onset Pompe disease. These reports suggested that cerebral vessel involvement could be an underrecognized complication of this disease.

METHODS

We report cerebral artery involvement in three French patients with late-onset Pompe disease.

RESULTS

The first patient died at age 35 years from complications of a giant fusiform aneurysm of the basilar artery, and her 34-year-old sister showed evidence of dolichoectatic basilar artery on magnetic resonance angiography. A dilative arteriopathy complicated with carotid artery dissection was diagnosed in the third patient, aged 50 years. Two patients are currently being treated with enzyme replacement therapy (alglucosidase alfa), and regular angiographic follow-up showed the absence of progression of vascular abnormalities in one of them.

CONCLUSION

These observations, combined with previously reported cases, confirm that Pompe disease should be recognized as a predisposing condition to dilative arteriopathy and cerebral aneurysm formation, although the real incidence of these vascular complications remains unknown.

Prevalence of papilloedema in patients with sleep apnoea syndrome: a prospective study

The association of papilloedema (PO) with respiratory diseases and especially obstructive sleep apnoea (OSA) syndrome has been emphasised in many reports. The pathophysiology could rely on the episodic increase of intracranial pressure related to apnoeic episodes during night sleep. Nevertheless, prevalence of papilloedema in patient with OSA syndrome remains unknown. As this information could improve diagnosis and therapeutic strategies, the aim of the present study was to investigate the prevalence of PO in an OSA syndrome population. From 95 successive, recently diagnosed OSA patients, 35 answered a questionnaire about visual symptoms and underwent fundoscopic examination. Visual symptoms suggestive of PO were present in 40% of the patients, but none had PO. As a conclusion, PO does not seem to be frequently associated with OSA syndrome and systematic screening of PO in these patients does not seem to be warranted. Nevertheless, patients with visual complaints evocative of papilloedema should have their eye fundus checked since the association between OSA and PO exists. Further studies, including more patients, might be useful to establish which patients are at particular risk for this complication.

Devenir des patients BPCO traités par ventilation non invasive prolongée à domicile

BACKGROUND

The use of domiciliary non-invasive positive pressure ventilation (NIPPV) is still controversial in stable hypercapnic COPD.

METHODS

Records of COPD patients who received home NIPPV from 1990 to 2002 either following an acute exacerbation or because of stable hypercapnia were retrospectively reviewed.

RESULTS

Thirty-seven patients receiving long term oxygen therapy for 50 +/- 47 months were included. At inclusion, their mean +/- SD: FEV1 was 27 +/- 9% predicted, inspiratory capacity was 45 +/- 14% predicted, PaO2 breathing room air was 50 +/- 10 mm Hg, PaCO2 breathing room air = 53 +/- 8 mm Hg, PaCO2 with oxygen was 60 +/- 9 mm Hg. Median survival with NIPPV was 41 months. The 1-year, 3-year and 5-year survival rates with NIPPV were 92%, 62% and 24% respectively. Twelve months after onset of home NIPPV, PaCO2 breathing room air and with oxygen were significantly lower (47 +/- 8 mm Hg, p = 0.028 and 53 +/- 8 mm Hg, p = 0.005, respectively), inspiratory capacity was significantly improved (54 +/- 18% predicted, p = 0.033).

CONCLUSION

This study suggests that home NIPPV allows a lasting physiological stabilization in selected COPD patients, particularly those with an advanced disease, by reducing hypercapnia and improving inspiratory capacity.

La gestion de la trachéotomie chez les patients adultes sous assistance ventilatoire à domicile

INTRODUCTION

Despite a large increase in the use of long term non-invasive ventilation domiciliary ventilation via a tracheostomy remains necessary in certain cases of severe respiratory insufficiency. The object of this article is to describe the technical and human management required in domiciliary ventilation by tracheostomy.

PERSPECTIVES

From the setting up of invasive ventilation in the home the choice of a tracheostomy tube to suit the patient and the management of the cuff by the patient or the family requires special attention by the prescribing physician. Currently humidification of the circuit is usually achieved by means of a hot water humidifier. Aspiration techniques, the changing and cleaning of the tracheostomy tube and the correct use of the speaking system need to be taught to the patient and the relatives. The main complications of domiciliary ventilation by tracheostomy are linked to the presence of the tube in the trachea and either mechanical (stenosis, granulomata, tracheal-oesophageal fistula) or infections.

CONCLUSIONS

The prescribing physician should call on health care providers whose staff are trained in domiciliary ventilation by tracheostomy and include in his team nurses who can continue the education of the patient and relatives.

Correlated strength in the nuclear spectral function

We have carried out an (e,e'p) experiment at high momentum transfer and in parallel kinematics to measure the strength of the nuclear spectral function S(k,E) at high nucleon momenta k and large removal energies E. This strength is related to the presence of short-range and tensor correlations, and was known hitherto only indirectly and with considerable uncertainty from the lack of strength in the independent-particle region. This experiment locates by direct measurement the correlated strength predicted by theory.

[Treatment of obstructive sleep apnea syndrome with mandibular advancement appliances]

Mandibular advancement device provide a therapeutic option for obstructive sleep apnea syndrome (OSAS). Clinical improvement has been proven in the different available studies, mainly on nocturnal respiratory events and quality of sleep. Less snoring have been noted by bed partners and objective studies have demonstrated a decrease in snoring frequency and intensity. The effects of these appliances on upper airways resistance syndrome is not yet well documented. The significant clinical improvement is secondary to the decrease in the occurrence of apneas and hypopneas. Polysomnographic improvement criteria with an apnea hypopnea index less than 10 per hour has been noted in certain cases, although no improvement or even worsening was noted in other cases. Sleep architecture has also changed in these patients, with a decrease in the time spent in stages 1 and 2, and an increase in the time spent in stages 3, 4 and rapid eye movement sleep. Micro-arousals are also reduced in number. Somnolence and loss of attention are improved; these have been evaluated subjectively or by a well known and approved somnolence scale. In some cases a test for vigilance was done. Our results are identical to those published in the different studies concerning respiratory events and sleep architecture.

Measurement of the electric form factor of the neutron through d-->(e-->,e(')n)p at Q2 = 0.5 (GeV/c)(2)

We report the first measurement using a solid polarized target of the neutron electric form factor G(n)(E) via d-->(e-->,e(')n)p. G(n)(E) was determined from the beam-target asymmetry in the scattering of longitudinally polarized electrons from polarized deuterated ammonia ( 15ND3). The measurement was performed in Hall C at Thomas Jefferson National Accelerator Facility in quasifree kinematics with the target polarization perpendicular to the momentum transfer. The electrons were detected in a magnetic spectrometer in coincidence with neutrons in a large solid angle segmented detector. We find G(n)(E) = 0.04632+/-0.00616(stat)+/-0.00341(syst) at Q2 = 0.495 (GeV/c)(2).

Principles of mandibular advancement device applied to the therapeutic of snoring and sleep apnea syndrome

Mandibular advancement device (MAD) represents a therapeutic option for simple snoring to obstructive sleep apnea syndrome (OSAS). The different available studies report an improvement either on nocturnal respiratory events or on the quality of sleep. The decrease in the intensity of snoring is confirmed by the patient's partner and by objective studies. For the time being the effects of these mandibular advancement devices on the upper airway resistance syndrome has not yet been well documented. The significant clinical improvement is secondary to the decrease in apnea hypopnea index (AHI). A polysomnographically proved cure has been reported with AHI < 10/h. Sleep architecture is also improved with wearing MAD demonstrating a decrease in the time passed in stage 1 sleep and an increase in slow wave sleep and rapid eye movement sleep (REM). A decrease in microarousals index has been shown. Daytime vigilance disorders are subjectively and objectively less remarkable. Then MAD can be beneficial for mild to moderate SAOS.

Nocturnal hypoventilation in chronic respiratory failure (CRF) due to neuromuscular disease

Decrease of respiratory muscle capacities in neuromuscular disease can lead to chronic respiratory failure with permanent alveolar hypoventilation. Respiratory centers elaborate a strategy of breathing dedicated to prevent overt respiratory muscles fatigue. This strategy may worsen chronic hypercapnia. During sleep, ventilation decreases because a lessening in respiratory centers function. During NREM sleep hypoventilation is only an exacerbation of what is seen during wakefulness. During REM sleep, atonia worsens much more hypoventilation particularly when diaphragmatic function is impaired. The effects of atonia are amplified by a very low reactivity of respiratory centers. Nocturnal mechanical ventilation improves nocturnal hypoventilation and daytime arterial blood gases (ABG). Mechanism of improvement in ABG and how nocturnal hypoventilation and diurnal hypoventilation interact, are still a matter of debate.

[Mandibular advancement orthoses used in the treatment of obstructive sleep apnea syndrome]

Mandibular advancement devices represent a therapeutic option for obstructive sleep apnea syndrome (OSAS). Clinical improvement has been proven in the different available studies, mainly on nocturnal respiratory events and quality of sleep. Less snoring have been noted by bed partners and objective studies have demonstrated decrease in snoring frequency and intensity. The effect of these ortheses on upper airways resistance syndrome is not yet well documented. The significant clinical improvement is secondary to the decrease in the occurrence of apneas and hypopneas. Polysomnographic improvement criteria with an apnea hypopnea index less than 10 per hour has been noted in certain cases. Although no improvement or even worsening was noted in other cases. Sleep architecture has also changed in these patients, with a decrease in the time spent in stages 1 and 2, and an increase in the time spent in stages 3 and 4 and rapid eye movement sleep. Micro-arousals are also decreased in number certainly with the decrease in the occurrence of respiratory events. Somnolence and loss of attention are improved; these have been evaluated subjectively or by a well known and approved somnolence scale. In some cases a test for vigilance was done.

[Mandibular advancement orthotic for treatment of obstructive sleep apnea]

Mandibular advancement devices represent a therapeutic option for obstructive sleep apnea syndrome (OSAS). Clinical improvement has been proved in the different available studies, mainly on nocturnal respiratory events and quality of sleep. Less snoring have been noted by bed partners and objective studies have demonstrated decrease in snoring frequency and intensity. The effect of these ortheses on upper airways resistance syndrome is not yet well documented. The significant clinical improvement is secondary to the decrease in the occurrence of apneas and hypopneas. Polysomnographic improvement criteria with an apnea hypopnea index less than 10 per hour has been noted in certain cases. Although no improvement or even worsening was noted in other cases. Sleep architecture has also changed in these patients, with a decrease in the time spent in stages 1 and 2, and an increase in the time spent in stages 3 and 4 and rapid eye movement sleep. Microarousals are also decreased in number certainly with the decrease in the occurrence of respiratory events. Somnolence and loss of attention are improved; these have been evaluated subjectively or by a well known and approved somnolence scale. In some cases a test for vigilance was done.