Forces created by mandibular advancement devices in OSAS patients: a pilot study during sleep.

BACKGROUND: The aim of this study was to measure forces created by progressive mandibular advancement with an oral device, during natural sleep, in a sample of adult patients with obstructive sleep apnea syndrome (OSAS). METHODS: A pressure transducer system was placed on the acrylic arms of a two-piece oral appliance (Herbst type) used by nine moderate to severe OSAS patients, in addition to all captors routinely used for polysomnography. Strains on the left and right sides were collected, during stable sleep stages without arousal, for each step of 1 mm advancement. RESULTS: The mean force in this sample was 1.18 N/mm and showed an almost linear evolution. Measurements showed intra- and inter-individual variability. CONCLUSION: The force values recorded in this study may explain the occlusal and skeletal side effects associated with long-term use of these oral appliances. They illustrate the influence of the extent of mandibular advancement, and indicate a possible dose-dependent effect.

Mutagenicity, genotoxicity, and scavenging activities of extracts from the soft coral Chromonephthea braziliensis: a possibility of new bioactive compounds.

Coral reefs are diverse ecosystems that have a high density of biodiversity leading to intense competition among species. These species may produce unknown substances, many with pharmacological value. Chromonephthea braziliensis is an invasive soft coral from the Indo-Pacific Ocean that is possibly transported by oil platforms and whose presence can be a threat to a region's biodiversity. This species produces secondary metabolites that are responsible for inducing damage to the local ecosystem. In the present study, extracts were prepared from dried colonies of C. braziliensis (solvents: hexane, dichloromethane, ethyl acetate, and methanol). We evaluated their mutagenicity using the Salmonella reverse mutation assay (TA97, TA98, TA100, and TA102 strains), their genotoxicity using the DNA breakage analysis and micronucleus assay, and scavenging activity using the 1,1-diphenyl-2-picrylhydrazyl-free radical assay. Cytotoxicity and mutagenicity were not observed for any of the extracts. Genotoxicity was observed for the dichloromethane, ethyl acetate, and methanol extracts at high concentrations, but no DNA damage was observed in the micronucleus assay. Scavenging activity was not detected.

[Radiation induced brachial plexopathy: Diagnosis, risk factors, principles of care]. / La plexite radique : épidémiologie, diagnostic, facteurs de risque et prise en charge.

Radiation plexitis, also known as radiation-induced brachial neuropathy is a rare toxicity following axillary, breast, cervical or thoracic radiotherapy, first described in 1966 by Stoll and Andrew. Although improvements in radiotherapy techniques have greatly reduced its risk over the past seventy years, its severe form remains a dreaded complication that is difficult to manage in patients with increased life expectancy. This article summarizes the epidemiological elements, risk factors, diagnostic methods, doses and constraints to be respected in radiotherapy and the treatment strategies of radiation plexitis.

[Interprofessional recommendations on behalf of Société française de radiothérapie oncologique for the prevention, protection and management of cyberattacks in radiation oncology]. / Prévention, protection, et gestion des cyberattaques en oncologie radiothérapie : recommandations interprofessionnelles au nom de la Société française de radiothérapie oncologique.

Cybersecurity is currently a major issue. Large hospitals are no longer the only main targets of attacks, but all healthcare organizations and establishments, without distinction of size or activities. The information system is defined as all the resources needed to collect images, store and process them with general distribution of multiple information within an organization. Systems are therefore crucial for the functioning of a medical department. Radiation oncology is one of the specialties most dependent on digital resources, for imaging, data transfer, dosimetry, treatment and so on.. Radiation oncology departments are therefore a prime target for ransomware attacks, which have increased significantly in recent years. Cybersecurity can be likened to a viral or bacterial attack. It is based on the two usual pillars of antimicrobial protection : hygiene and prophylaxis. In this article, we will detail by analogy the three classic levels of prevention of a bacillary attack: "primary prevention", which acts upstream of the infection; "secondary prevention", which acts at an early stage of its evolution; and "tertiary prevention", which acts on complications and risks of recurrence. This article is the result of an interprofessional group on behalf of SFRO, the French society of radiation oncology, with the aim of helping all teams to implement safety adapted to the specificities of a radiation oncology department in France.

Transparent coatings made from spray deposited colloidal suspensions.

The goal of this study is to elaborate few-micrometer thick optically active coatings based on nanoparticles spray-deposited onto a substrate and to control their scattering properties through a progressive suppression of the coffee-ring effect. The modification of the aggregation state of the nanoparticles to be sprayed induces a change of the surface roughness of the films and consequently of their optical transmission. We draw the counterintuitive conclusion that a nonstable colloidal solution gives a smoother coating than a highly stabilized colloidal solution, leading to a more transparent coating. This phenomenon is demonstrated in the case of commercial TiO(2) nanoparticles, as well as of homemade luminescent YVO(4):Eu nanoparticles, and seems to be generalized to a large range of systems.

[Securing the information system of health care organisations]. / Sécurisation du système d'information des structures médicales.

The information system involves all the resources managing information within a team. It mainly relies on the computer network. Prevention and protection measures are vital, especially in a radiotherapy department. They will aim to preserve the whole staff from potential risks connected with passwords, suspicious emails, specific websites, or USB flash drives. Also, they will consist in maintaining updated operating systems and software, activating antivirus programs and firewalls, and getting a map of the whole network and its users. Finally, it is necessary to anticipate failure scenarios and to set up recovery plans to continue the activity with lower resources.

[Low dose radiotherapy for COVID-19 pneumopathy: Biological rationale and literature review]. / Radiothérapie de faible dose pour la pneumopathie covid-19 : rationnel biologique et revue de la littérature.

The world has now been facing the coronavirus disease 2019 (COVID-19) pandemic due to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) since over a year. If most of clinical presentations are benign, fragile patients are at greater risk of developing severe or fatal lung disease. Many therapies have been explored with very low impact on mortality. In this context, Kirkby et Mackenzie have published in April 2020 a report reminding the anti-inflammatory properties of low-dose radiotherapy (delivering less than 1Gy) and its use in the treatment of viral and bacterial pneumopathies before antibiotics era. Large in vivo and in vitro data have demonstrated the biological rationale and anti-inflammatory activity of low-dose radiotherapy in many pathologies. Over the past year, three phase I/II clinical trials have been published, as well as one randomized controlled trial, reporting the feasibility and the clinical and biological improvement of a 0.5 to 1Gy treatment dose to the entire lung. 13 other studies, including a randomized phase III trial, are currently ongoing worldwide. These studies may provide data in the effect of low-dose radiotherapy in the treatment of SARS-CoV-2 pneumonia. This article explains biological rationale of low-dose radiotherapy, and reports already published or ongoing studies on low-dose radiotherapy for SARS-CoV-2 pneumonia.

Titrated mandibular advancement versus positive airway pressure for sleep apnoea.

The aim of this study was to compare mandibular advancement device (MAd) therapy and continuous positive airway pressure (CPAP) for obstructive sleep apnoea/hypopnoea syndrome (OSAHS) after one-night polysomnographic (PSG) titration of both treatments. 59 OSAHS patients (apnoea/hypopnoea index (AHI): 34+/-13 events x h(-1); Epworth scale: 10.6+/-4.5) were included in a crossover trial of 8 weeks of MAd and 8 weeks of CPAP after effective titration. Outcome measurements included home sleep study, sleepiness, health-related quality of life (HRQoL), cognitive tests, side-effects, compliance and preference. The median (interquartile range) AHI was 2 (1-8) events x h(-1) with CPAP and 6 (3-14) events x h(-1) with MAd (p<0.001). Positive and negative predictive values of MAd titration PSG for treatment success were 85% and 45%, respectively. Both treatments significantly improved subjective and objective sleepiness, cognitive tests and HRQoL. The reported compliance was higher for MAd (p<0.001) with >70% of patients preferring this treatment. These results support titrated MAd as an effective therapy in moderately sleepy and overweight OSAHS patients. Although less effective than CPAP, successfully titrated MAd was very effective at reducing the AHI and was associated with a higher reported compliance. Both treatments improved functional outcomes to a similar degree. One-night titration of MAd had a low negative predictive value for treatment success.

[The set-up of obstructive sleep apnea treatment]. / Mise en place du traitement du SAHOS.

The therapeutic strategy of obstructive sleep apnea syndrome (OSAS) is dependent on the illness severity, which is influenced by several factors as the presence of comorbidities (particularly cardiovascular comorbidities), the importance of diurnal drowsiness and the number of abnormal respiratory events. Whereas the treatment is most often palliative and uncomfortable, its success is closely dependent on its compliance. The way of starting the treatment of OSAS is therefore an essential topic, which will condition its long-term acceptance.

Environmental matching used to predict range expansion of two invasive corals (Tubastraea spp.).

The scleractinian corals Tubastraea coccinea Lesson, 1829 and T. tagusensis Wells, 1982 have invaded reefs along Brazil's coastline. Over the period 2011-2017 a standard, fast, easily repeatable semi-quantitative method was used to produce maps of distribution and a site (n = 77) specific Relative Abundance Index (RAI) to determine range expansion at Cabo Frio, an upwelling region. Invaded sites doubled from six to 12 over the period (one per year) and mean abundance increased tenfold from 0.2 to 2.6 RAI and 0.22 to 1.8 RAI (T. coccinea and T. tagusensis respectively). Site specific oceanographic conditions (temperature, salinity and water transparency) and distance from currently invaded sites (a proxy for propagule pressure) were chosen and used as determinants of invasion success in order to model the expansion. Model results compared favourably with empirical measurements and the simple, regional, and spatially explicit model predicted future range expansion under 10 and 20 year scenarios.

[Alcohol problems in drinking drivers and clinical management methods]. / Typologie des contrevenants à l'alcoolémie routière et modalités des prises en charge.

BACKGROUND: In order to improve knowledge on the typology of drinking drivers, their clinical management and their outcome in terms of alcohol consumption following treatment, 1086 drinking drivers attending one of the 18 outpatient centres for the care of alcoholics participating to the study were studied; those requiring long-term therapy or those mandated to treatment were followed-up during one year. Most of them (95%) were men with a mean age of 38 years. The drinking-driving offence was recorded during an alcohol spot-check (62%), following a traffic accident (23%) or a traffic offence (15%). For 35%, it was the second offence and 19% have been mandated to treatment. Alcohol consumption before checking were based on spirits in 67% of cases and only wine or beer for the remaining 33%. Severe alcohol problems (i.e. abuse or dependence) were diagnosed in 38%, both in men and women. Mean blood alcohol level was 1.6 g/l, without any difference according to sex; it was significantly increased in those checked following a traffic accident, in those having drank spirits, wine and beer and in those having a severe alcohol problem. Follow-up was organized for those mandated to treatment and for a third of the others, including mainly those second-offenders and those with a severe alcohol problem. Observance to appointments were similar in both groups. At the end of follow-up (350 subjects were concerned), 75% were either non- or moderate drinkers while the 25% remaining were still abuser or dependent; the single parameter independently and significantly associated to an absence of alcohol behaviour improvement was "to be mandated to treatment" (RR=4.4 CI [2.03-9.69], p<0.001). Our results confirm the high prevalence of severe alcohol problems in drinking drivers and demonstrate that women are concerned as much as men. They assess that since increased blood alcohol levels in drivers are observed whatever the type of alcoholic beverages consumed, all these latter without any exception are dangerous when drank in excess before driving. Finally, our results suggest that mandating to treatment a drinking driver should be discussed and its efficacy revisited.

[Central apnea developing during treatment with a mandibular advancement device]. / Apnées centrales induites sous traitement par orthèse d'avancée mandibulaire.

INTRODUCTION: Mandibular advancement (MA) has emerged over the last decade as an alternative solution to nasal continuous airway pressure (nCPAP) for the treatment of obstructive sleep apnea syndrome (OSAS). OBSERVATION: We report the case of a patient with history of chronic atrial fibrillation and moderate supine-dependent OSAS in whom central sleep apneas developed during treatment by a bi-bloc MA device. Central apneas increased with the level of MA and preferentially occurred in the supine position. We hypothesized that mouth opening under excessive mandibular advancement in supine position may have led to pharyngeal narrowing at the base of the tongue and potentially unstable ventilation. Sleep fragmentation that enhanced during progressive MA may also have compromised ventilatory control stability in our patient. Finally, chronic atrial fibrillation may have predisposed to central sleep apneas. CONCLUSION: Our case report highlights the importance of follow-up nocturnal recordings during progressive MA.

[Risk analysis study for patients care in radiotherapy: Learning curve and methodological evolution]. / Étude des risques a priori encourus par les patients en radiothérapie : courbe d'apprentissage et évolution méthodologique.

PURPOSE: To describe the evaluation of our risk mapping methodology over the past two years. MATERIALS AND METHODS: Based on the FMEA (failure mode effects analysis) method, some aspects have been adapted, e.g. the concept of risk control and effort scale, some others have been introduced, e.g. the concept of residual risk management. A weekly meeting is scheduled by a multidisciplinary team in order to support the different projects. RESULTS: Experiments and practice have led us to upgrade our scales of gravity and detectability, identify critical points and introduce the residual risk management concept. Some difficulties with regards to the multiplicity of scenarios still prevail. CONCLUSION: Risk mapping is an essential tool in the implementation of risk quality management, specifically when the methodology is progressive and takes into consideration all the members of a pluridisciplinary team.

[Interobserver variability study for daily cone beam computed tomography registration of prostate volumetric modulated arc therapy]. / Tomographie conique quotidienne pour les traitements pelviens et prostatiques: étude interobservateurs.

PURPOSE: This work evaluated the interobserver variability in cone beam computed tomography (CBCT) registration for prostate cancers treated with intensity-modulated radiotherapy. MATERIAL AND METHODS: Twelve technologists realized 286 CBCT/CT registrations (bone registration followed by prostate to prostate registration). The registration results were compared to those obtained by two radiation oncologists (reference). Each technologist reported the shifts calculated by the software in all three axes. A statistical analysis allowed us to calculate the minimum threshold under which 95% of the observers found similar values. A variance analysis followed by the post hoc test were used to find differences in interobserver registration variability and determine whether any individual users performed registrations which differed significantly from those of the other users. RESULTS: The registration differences compared to the reference in the three directions in terms of 95th percentile are: 2.1mm left-right, 3.5mm target-gun, 7.3mm anterior-posterior. In the posterior direction, 4% of the observers have found differences superior to 8mm, margin used in routine without the use of a daily CBCT. The variance test revealed a P-value <0.05 only for target-gun and for all observers there was no significant difference compared to the reference. CONCLUSION: This study confirmed the interest of a 3D tissue registration for prostate treatments. The registration study showed a good interobserver reproducibility. This showed the importance of a daily CBCT/CT registration in prostate treatment with the possibility of a planning target volume margin reduction in the three directions. An evaluation of a partial delegation of registration to technologists should be done by the radiation oncologists.

Total amounts of circulating human chorionic gonadotrophin alpha and beta subunits can be assessed throughout human pregnancy using immunoradiometric assays calibrated with the unaltered and thermally dissociated heterodimer.

The aim of the present study was to determine the variations in the balance between total (free plus combined) circulating alpha and beta subunits of human chorionic gonadotrophin (hCG) throughout human pregnancy. The equivalence between the International Units (IU) of hCG (IRP 75/537) and those assigned to the alpha (IRP 75/569) and beta (IRP 75/551) free subunits was experimentally determined by using intact and thermally dissociated hCG. Heat exposure (2 min at 100 degrees C) of hCG preparations resulted in a complete dissociation of hCG into free, soluble and intact alpha and beta subunits. The hCG and alpha and beta subunit contents of unaltered and heated hCG preparations were assessed by specific immunoradiometric assays. The amount of immunoreactive subunits dissociated by heat from hCG could then be evaluated on a molar basis. Circulating hCG and its free alpha and beta subunits were immunoassayed in 836 blood samples collected from healthy pregnant women at different gestational ages. After conversion of hCG and its subunits into a common IU system, the gestational profiles of the total amounts (free plus combined) of alpha- and beta hCG subunits increased together and peaked at 9-10 weeks of gestation. Thereafter, total alpha and beta subunits decreased and subsequently remained stable until term. The decline in total alpha hCG subunit was less marked than that of total beta hCG subunit. The alpha- to beta hCG ratio was equimolar until 10 weeks of gestation when it increased almost fourfold until term (P < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Sleep apnea syndrome in the elderly.

Sleep apnea syndrome (SAS) is a well established sleep disorder with high morbidity and mortality. Patients are most often middle-aged men. SAS occurs in at least 1% of the adult population. Several studies have suggested that SAS is extremely frequent in the elderly, its prevalence ranging from 18 to 73% in this group. However, the generalization of these results to elderly cohorts is questionable because of several limitations of these studies, including lack of standard selection criteria, variation in recording techniques, the night to night variability of sleep apnea and the use of a moderate level of sleep disordered breathing (SDB) to define SAS (5 apneas per hour). The study best designed for valid extrapolation to the whole aged population estimates the frequency of SAS at 18%. However, most of these patients reported satisfactory sleep, and epidemiologic criteria for a causal association between SAS in the elderly and cardiovascular disease have not been satisfied. The conclusions of numerous studies dealing with impairment in cognitive function and SAS in the elderly are controversial. In fact, if the diagnostic threshold is increased from 5 apneas to 10 apneas plus hypopneas per hour, elderly SAS patients have more sleep disturbances, are more depressed and have cognitive deficits as compared to normal old persons. When an appropriate diagnostic index is used, SAS in the elderly resembles SAS described in the middle-aged population. In addition, a high apnea plus hypopnea index is an ominous predictor of mortality in the elderly population, and a very high level of SDB is an extremely significant risk factor for mortality during sleep phase in these patients.(ABSTRACT TRUNCATED AT 250 WORDS)

A laboratory validation study of the diagnostic mode of the Autoset system for sleep-related respiratory disorders.

We performed a validation study of the diagnostic mode of the Autoset system (ResMed, Australia) on a group of 44 snorers (10 women). We compared the result of the Autoset's automatic analysis of nasal airflow (using nasal prongs) to those of an in-laboratory polysomnographic study with a Fleisch facemask pneumotachograph. For the first 29 patients, the Autoset software was set to recognize only apneas; for the remaining 15, the software was modified to recognize both apneas and hypopneas. Relative to polysomnography, the Autoset overestimated the number of apneas. Oral breathing or displacement of the nasal prongs partially explained these differences. A significant correlation was found between the apnea indices (AI) assessed by the two methods (r = 0.98). For an AI of 20/hour the Autoset was 100% sensitive and 88% specific. The Autoset significantly underestimated the number of hypopneas compared to the polysomnograph with pneumotachograph (62.9 +/- 4.7 vs. 85.5 +/- 73.1, P = 0.04), although for an apnea-hypopnea index of 20, Autoset was 100% sensitive and 88% specific. The lack of linearity of Autoset's volume evaluation at low volumes could explain most of the differences. Our results indicate that the Autoset system, in its diagnostic mode, is a useful tool for identifying patients with significant obstructive sleep apnea syndrome. The system is less useful in patients with mild to moderate sleep disordered breathing, where it may give erroneous results.

Long-term compliance to continuous positive airway pressure therapy (nCPAP) set up during a split-night polysomnography.

We studied prospectively the acute and long-term compliance with nasal continuous positive airway pressure (nCPAP) therapy set up during a split-night polysomnography in 31 patients suffering from severe obstructive sleep apnea syndrome (OSAS). The mean apnea-hypopnea index (AHI) was 66 +/- 23/hour. An effective nCPAP (AHI < 10/hour in all sleep stages in the dorsal decubitus) was titrated in 27/31 patients. The mean effective nCPAP was 11 +/- 2 cm H2O. In three patients, a subsequent night was necessary to determine the effective nCPAP during rapid eye movement sleep, and one patient did not support the treatment. Of the 27 patients with successful titration, 21 accepted home treatment, three chose a surgical procedure and three refused to be treated. Of the 21 accepting home treatment, one patient did not receive his insurance agreement and could not participate in follow-up. Among the 20 other patients, four interrupted their treatment during the 1st month because of discomfort, and 16 were followed for 285 +/- 84 days. The daily rate of nCPAP use for the compliant patients was 6.7 +/- 1.5 hours. These preliminary results indicate that a split-night technique is reliable and cost saving in a majority of patients suffering from severe OSAS.

Long-term efficacy of fixed CPAP recommended by Autoset for OSAS.

The Autoset autotitration system (Resmed, Australia) was designed as an aid for determination of the effective level of CPAP. Two studies have shown that the 95% pressure centile during a night with Autoset, after excluding any periods with severe leak (P95), was well correlated with the pressure determined manually according to the reference method. However, the suitability of P95 under Autoset for treatment with conventional CPAP needed to be evaluated outside of the context of titration. The objective of this study was to measure the compliance and efficacy of CPAP at P95 determined by Autoset, after 3 months. Twenty-four patients who had undergone routine autotitration by Autoset under polysomnographic control in the laboratory for previously untreated OSAS were evaluated after 3 months of treatment with CPAP at P95. This evaluation was based on compliance, daily usage, determined by reading the hourly counter, Epworth sleepiness score and home respiratory recording under CPAP. Polysomnography under Autoset showed a significant reduction of abnormal respiratory events (apnea-hypopnea index (AHI): 5.7 (+/-4.6) vs 69.6 (+/-29.8) n/h; p<0.001). P95 was between 8.5 and 15 cm H2O (mean: 11.2 (+/-1.6)). Two patients were lost to follow-up. At 3 months, 18 out of 22 (82%) patients declared that they were still using their machine with a daily usage of 5.25 (+/-1.82) h. The Epworth sleepiness scale was significantly decreased (5 (+/-4.1) vs 11.4 (+/-5.4); p<0.05). P95 recommended by Autoset remained effective on abnormal respiratory events with a low AHI (4.1 (+/-3.2) n/h) and a low 4% oxygen desaturation index (3.6 (+/-4.5) n/h) under CPAP. This study confirms the efficacy of autotitration and the suitability of P95 determined by Autoset for long-term treatment by conventional CPAP at home.

The cost of treating COPD patients with long-term oxygen therapy in a French population.

OBJECTIVE: In greater Paris and its surrounding (as it is in all France), oxygen is home delivered by not-for-profit (NP) associations or profit-making (PM) health organizations. Both are financed by the national health insurance. This dual context and the current economic climate justify an economic evaluation of all respiratory care for patients with COPD receiving long-term oxygen therapy (LTO). This pragmatic approach identifies the variables that have the greatest impact on direct medical costs and estimates the annual cost for respiratory care per COPD patient. DESIGN: Retrospective study. SETTING: Health insurance scheme for self-employed professionals (CANAM). PATIENTS AND METHODS: Between July 1985 and March 1994, 234 patients registered in CANAM files began LTO, 24% in the PM sector, 76% in the NP sector, mainly using concentrator (78%), mean age of 74 +/- 10 years, male predominance (74%), PaO2 of 56.2 +/- 10.5 mm Hg, FEV1/FVC of 43 +/- 15%, and 51% having 1 or more severe illness(es) associated. The economic appraisal was performed on a representative sample of 61 patients and measured the total resources consumption for respiratory care per COPD patient and per year (physician visits and tests, drugs, physiotherapy, oxygen therapy, hospitalizations for acute respiratory failure, transport costs). RESULTS: A quarter of the patients in each sector did not meet the LTO prescription guidelines (PaO2 > 60 mm Hg). For patients having their oxygen delivered by NP sector, the total ambulatory cost for respiratory care was lower ($4,506 per patient and per year vs $5,399) because they mainly used concentrator, all the other direct ambulatory costs being equal. The total annual cost for respiratory care of a COPD patient receiving LTO amounted to $11,672 (NP and PM sectors merged). Oxygen therapy represented 73% of the total ambulatory cost. In a multiple linear regression model, hospitalization represented the largest share of cost, significantly higher when PaO2 was 55 mm Hg or less ($2,287 per patient per year vs $8,717). In contrast, none of the covariates (age, sex, PaO2, FEV1/FVC) influenced at a significant level the total cost of visits, tests, drugs, and physiotherapy, amounting to $1,507. CONCLUSION: As oxygen treatment plays an important role in the variation of costs, further pragmatic studies should help to better understand what are the real motivations to choose one mode of oxygen administration more than another and should determine factors that may lead physicians sometimes not to comply with clinical guidelines.