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International audience; COVID-19 lockdowns have deeply impacted teaching programs. Online teaching has suddenly become the main form of medical education, a form that may be used as long as the pandemic continues. We aimed at analyzing how online teaching was perceived by both teachers and learners to help determine how to adapt curricula in the next few years. An anonymous cross-sectional survey of medical students, pediatric residents, neonatal fellows, and their respective teachers was conducted between June and August 2020 to assess feelings about quality, attendance, equivalence, and sustainability of online teaching programs. 146 Students and 26 teachers completed the survey. 89% of students agreed that the offered online teaching was an appropriate way of teaching during the pandemic. Less than half of learners and teachers felt they have received or provided a training of an equivalent level and quality as in usual courses. About one-third thought that this online teaching should continue after the crisis ends. Medical school students had significantly more mixed opinions on online teaching than residents and fellows did. Attendance of learners significantly improved with synchronous online classes (p < 0.001), and among more advanced learners (p < 0.002). Our study is the first of this kind to assess simultaneously the feelings of learners at different levels (medical students, residents, and fellows) and their respective teachers of pediatric on programs taught online. It showed that online programs were perceived as appropriate ways of teaching during the COVID pandemic. Further studies are, however, needed to assess the efficacy of such teaching methods on medical skills and communication capabilities.

Type 2 acrodysostosis (ACRDYS2), a rare developmental skeletal dysplasia characterized by short stature, severe brachydactyly and facial dysostosis, is caused by mutations in the phosphodiesterase (PDE) 4D (PDE4D) gene. Several arguments suggest that the mutations should result in inappropriately increased PDE4D activity, however, no direct evidence supporting this hypothesis has been presented, and the functional consequences of the mutations remain unclear. We evaluated the impact of four different PDE4D mutations causing ACRDYS2 located in different functional domains on the activity of PDE4D3 expressed in Chinese hamster ovary cells. Three independent approaches were used: the direct measurement of PDE activity in cell lysates, the evaluation of intracellular cAMP levels using an EPAC-based (exchange factor directly activated by cAMP) bioluminescence resonance energy transfer sensor , and the assessment of PDE4D3 activation based on electrophoretic mobility. Our findings indicate that PDE4D3s carrying the ACRDYS2 mutations are more easily activated by protein kinase A-induced phosphorylation than WT PDE4D3. This occurs over a wide range of intracellular cAMP concentrations, including basal conditions, and result in increased hydrolytic activity. Our results provide new information concerning the mechanism whereby the mutations identified in the ACRDYS2 dysregulate PDE4D activity, and give insights into rare diseases involving the cAMP signaling pathway. These findings may offer new perspectives into the selection of specific PDE inhibitors and possible therapeutic intervention for these patients.

In humans, activating mutations in the PRKAR1A gene cause acrodysostosis 1 (ACRDYS1). These mutations result in a reduction in PKA activation caused by an impaired ability of cAMP to dissociate mutant PRKAR1A from catalytic PKA subunits. Two striking features of this rare developmental disease are renal resistance to PTH and chondrodysplasia resulting from the constitutive inhibition of PTHR1/Gsa/AC/cAMP/PKA signaling. We developed a knock-in of the recurrent ACRDYS1 R368X PRKAR1A mutation in the mouse. No litters were obtained from [R368X]/[+] females (thus no homozygous [R368X]/[R368X] mice). In [R368X]/[+] mice, Western blot analysis confirmed mutant allele heterozygous expression. Growth retardation, peripheral acrodysostosis (including brachydactyly affecting all digits), and facial dysostosis were shown in [R368X]/[+] mice by weight curves and skeletal measurements (μCT scan) as a function of time. [R368X]/[+] male and female mice were similarly affected. Unexpected, however, whole-mount skeletal preparations revealed a striking delay in mineralization in newborn mutant mice, accompanied by a decrease in the height of terminal hypertrophic chondrocyte layer, an increase in the height of columnar proliferative prehypertrophic chondrocyte layer, and changes in the number and spatial arrangement of proliferating cell nuclear antigen (PCNA)-positive chondrocytes. Plasma PTH and basal urinary cAMP were significantly higher in [R368X]/[+] compared to WT mice. PTH injection increased urinary cAMP similarly in [R368X]/[+] and WT mice. PRKACA expression was regulated in a tissue (kidney not bone and liver) manner. This model, the first describing the germline expression of a PRKAR1A mutation causing dominant repression of cAMP-dependent PKA, reproduced the main features of ACRDYS1 in humans. It should help decipher the specificity of the cAMP/PKA signaling pathway, crucial for numerous stimuli. In addition, our results indicate that PRKAR1A, by tempering intracellular cAMP levels, is a molecular switch at the crossroads of signaling pathways regulating chondrocyte proliferation and differentiation. © 2016 American Society for Bone and Mineral Research.

To investigate whether low-dose mitotane (up to 2 g/day) could be a temporary therapeutic alternative to transsphenoidal surgery (TSS) in pediatric Cushing’s disease (CD). Twenty-eight patients with CD aged 12.2 years (± 2.2) were referred to our center. We compared nine patients treated with mitotane alone for at least 6 months to 13 patients cured after surgery. Primary outcomes were changes in growth velocity, BMI and pubertal development. The following results were obtained: (1) Mitotane improved growth velocity z-scores (−3.8 (±0.3) vs −0.2 (±0.6)), BMI z-scores (2.1 (±0.5) vs 1.2 (±0.5) s.d.) and pubertal development. After 1 year on mitotane, the mean BMI z-score was not significantly different in both groups of patients. (2) Control of cortisol secretion was delayed and inconsistent with mitotane used as monotherapy. (3) Side effects were similar to those previously reported, reversible and dose dependent: unspecific digestive symptoms, concentration or memory problems, physical exhaustion, adrenal insufficiency and hepatitis. (4) In one patient, progressive growth of a pituitary adenoma was observed over 40 months of mitotane treatment, allowing selective adenomectomy by TSS. In conclusions, low-dose mitotane can restore growth velocity and pubertal development and decrease BMI in children with CD, even without optimal control of cortisol secretion. It may promote pituitary tumor growth thus facilitating second-line TSS. However, given its possibly life-threatening side effects (transient adrenal insufficiency and hepatitis), and in the absence of any reliable follow-up procedures, this therapy may be difficult to manage and should always be initiated and monitored by specialized teams.

In acrodysostosis without hormone resistance, a disease caused by phosphodiesterase (PDE)-4D mutations, increased PDE activity leads to bone developmental defects but with normal renal responses to PTH. To identify potential mechanisms for these disparate responses, we compared the effect of PDE activity on hormone signaling through the GPCR-Gsα-cAMP-PKA pathway in cells from two lineages, HEK-293 cells stably overexpressing PTH1R (HEKpthr) and human dermal fibroblasts, including studies evaluating cAMP levels using an Epac-based BRET-sensor for cAMP (CAMYEL). For ligand-induced responses inducing strong cAMP accumulation, the inhibition of PDE4 activity resulted in relatively small further increases. In contrast, when ligand-induced cAMP accumulation was of lesser intensity, the inhibition of PDE4 had a more pronounced effect. Similar results were obtained evaluating downstream events (cellular CREB phosphorylation and CRE-luciferase activity). Thus, the ability of PDE4 to modulate signaling through GPCR-cAMP-PKA pathways can depend on the cell type and stimulus intensity.

In humans, activating mutations in the PRKAR1A gene cause acrodysostosis 1 (ACRDYS1). These mutations result in a reduction in PKA activation caused by an impaired ability of cAMP to dissociate mutant PRKAR1A from catalytic PKA subunits. Two striking features of this rare developmental disease are renal resistance to PTH and chondrodysplasia resulting from the constitutive inhibition of PTHR1/Gsa/AC/cAMP/PKA signaling. We developed a knock-in of the recurrent ACRDYS1 R368X PRKAR1A mutation in the mouse. No litters were obtained from [R368X]/[+] females (thus no homozygous [R368X]/[R368X] mice). In [R368X]/[+] mice, Western blot analysis confirmed mutant allele heterozygous expression. Growth retardation, peripheral acrodysostosis (including brachydactyly affecting all digits), and facial dysostosis were shown in [R368X]/[+] mice by weight curves and skeletal measurements (μCT scan) as a function of time. [R368X]/[+] male and female mice were similarly affected. Unexpected, however, whole-mount skeletal preparations revealed a striking delay in mineralization in newborn mutant mice, accompanied by a decrease in the height of terminal hypertrophic chondrocyte layer, an increase in the height of columnar proliferative prehypertrophic chondrocyte layer, and changes in the number and spatial arrangement of proliferating cell nuclear antigen (PCNA)-positive chondrocytes. Plasma PTH and basal urinary cAMP were significantly higher in [R368X]/[+] compared to WT mice. PTH injection increased urinary cAMP similarly in [R368X]/[+] and WT mice. PRKACA expression was regulated in a tissue (kidney not bone and liver) manner. This model, the first describing the germline expression of a PRKAR1A mutation causing dominant repression of cAMP-dependent PKA, reproduced the main features of ACRDYS1 in humans. It should help decipher the specificity of the cAMP/PKA signaling pathway, crucial for numerous stimuli. In addition, our results indicate that PRKAR1A, by tempering intracellular cAMP levels, is a molecular switch at the crossroads of signaling pathways regulating chondrocyte proliferation and differentiation. © 2016 American Society for Bone and Mineral Research.

There are presently only scant data published about neonatal diaphragmatic paralysis and the options for its clinical management. We observed a case of unilateral diaphragmatic paralysis secondary to thoracic surgery in a preterm neonate, and we successfully managed it using neurally adjusted ventilator assist (NAVA) whose data have been electronically recorded in real time. Parents gave written consent for publication. A preterm female baby, born at 25 weeks’ gestation, was diagnosed with haemodynamically patent ductus arteriosus, which needed surgical closure since two cures of ibuprofen failed to close it. After the surgery, she could not be weaned from mechanical ventilation for 26 days; chest X-rays revealed elevation of the left hemidiaphragm and targeted ultrasound confirmed the hemidiaphragmatic paralysis. The patient was shifted to invasive NAVA with Servo-i (Maquet, Solna, Sweden) and then finally extubated on biphasic positive airway pressure ventilation (BiPAP) through a nasal mask, as this is our routine clinical protocol. The NAVA level used was set at 4 cmH2O/μV and gradually decreased to 1 by steps of 0.5 cmH2 …

The use of ketoconazole has been recently questioned after warnings from the European Medicine Agencies and the Food and Drug Administration due to potential hepatotoxicity. However, ketoconazole is frequently used as a drug to lower circulating cortisol levels. Several pharmacological agents have recently been approved for the treatment of Cushing's disease (CD) despite limited efficacy or significant side effects. Ketoconazole has been used worldwide for more than 30 years in CD, but in the absence of a large-scale study, its efficacy and tolerance are still under debate.We conducted a French retrospective multicenter study reviewing data from patients treated by ketoconazole as a single agent for CD, with the aim of clarifying efficacy and tolerance to better determine the benefit/risk balance.Data from 200 patients were included in this study. At the last follow-up, 49.3% of patients had normal urinary free cortisol (UFC) levels, 25.6% had at least a 50% decrease, and 25.4% had unchanged UFC levels. The median final dose of ketoconazole was 600 mg/d. Forty patients (20%) received ketoconazole as a presurgical treatment; 40% to 50% of these patients showed improvement of hypertension, hypokalemia, and diabetes, and 48.7% had normal UFC before surgery. Overall, 41 patients (20.5%) stopped the treatment due to poor tolerance. Mild (5N, inferior to 5-fold normal values) and major (5N, superior to 5-fold normal values) increases in liver enzymes were observed in 13.5% and 2.5% of patients, respectively. No fatal hepatitis was observed.Ketoconazole is an effective drug with acceptable side effects. It should be used under close liver enzyme monitoring. Hepatotoxicity is usually mild and resolves after drug withdrawal.

The skeletal dysplasia characteristic of acrodysostosis resembles the Albright's hereditary osteodystrophy seen in patients with pseudohypoparathyroidism type 1a, but defects in the α-stimulatory subunit of the G-protein (GNAS), the cause of pseudohypoparathyroidism type 1a, are not present in patients with acrodysostosis. We report a germ-line mutation in the gene encoding PRKAR1A, the cyclic AMP (cAMP)-dependent regulatory subunit of protein kinase A, in three unrelated patients with acrodysostosis and resistance to multiple hormones. The mutated subunit impairs the protein kinase A response to stimulation by cAMP; this explains our patients' hormone resistance and the similarities of their skeletal abnormalities with those observed in patients with pseudohypoparathyroidism type 1a.

Introduction Plusieurs mutations des PDE4D, une des quatre sous-familles PDE4 impliquees specifiquement dans la degradation de l’AMPc ont ete identifiees dans l’acrodysostose sans resistance hormonale. Le phenotype osseux indique une perte d’activation de la voie cAMP-PKA. Le but du travail est de caracteriser les consequences fonctionnelles de ces mutations. Materiels et methodes Quatre mutations des PDE4D, localisees dans trois domaines fonctionnels caracterisant cette famille, ont ete introduites par mutagenese dirigee dans le plasmide pcDNA3-hPDE4D3. La fonction des PDE4D est mesuree apres transfection transitoire dans les cellules CHO, en condition basale, stimulee, avec ou sans inhibiteur specifique (rolipram) via : – la mesure de l’activite PDE4D (technologie de BRET via l’utilisation d’un biosensor EPAC et mesure de l’hydrolyse d’AMPc-H3) ; – la mesure de l’activite de la PKA (systeme rapporteur CRE-luciferase). Resultats L’expression des proteines mutees est similaire a celle de la PDE4D sauvage. Les mutants ont une activite augmentee par rapport au sauvage par technique de BRET et par mesure d’hydrolyse d’AMPc-H3. L’activite PKA est inhibee par les mutants. Cette inhibition est reversee de facon concentration-dependante par le rolipram, avec une sensibilite au rolipram des mutants diminuee par rapport au sauvage. Quelle que soit la localisation des mutations, les resultats sont similaires. Discussion/conclusion Les 4 mutants PDE4D etudies entrainent une augmentation de l’activite PDE4D en condition basale et stimulee et modifient leur sensibilite au rolipram. Ces resultats sont compatibles avec un gain de fonction des PDE4D mutees causant une perte d’activation de la voie cAMP-PKA.

Introduction – ObjectiveWe know today that newborns are capable of feeling pain and that even healthy term newborns are bound to undergo painful procedures during the neonatal period.The main goal of this study was to better the understanding of how newborns pain was managed in the delivery ward as well as in the maternity ward. The second goal was to elaborate some new tools to improve the medical management of pain. MethodTo try to answer those questions, we led a qualitative study by interviewing midwives that worked in 3 different levels of maternity of Île-de-France.Results and conclusionOur study showed that only a few midwives followed a specific training about the pain management of newborns, that the idea of pain itself and its scoring were subjective, that the most used scale to score pain was the EDIN scale, and that non medical treatment of pain were largely used among midwives. We couldn’t conclude on the presence of differences in the management of pain between the different hospitals that we interviewed.Pain being subjective, the improvement of its management probably requires training of the caregivers as well as updated protocols of service.; Introduction - ObjectifsTous les nouveau-nés, y compris ceux à terme et en bonne santé sont amenés à subir des gestes douloureux lors de la période néonatale.L’objectif principal de cette étude était de mieux comprendre la prise en charge de la douleur chez les nouveau-nés en salle de naissance et en maternité. L’objectif secondaire était d'élaborer des pistes d'amélioration de cette prise en charge.Matériel et méthodePour tenter d’apporter des éléments de réponse à cette question, nous avons mené une étude qualitative sous forme d’entretiens semi-dirigés auprès de sages-femmes de trois maternités d’Île-de-France.Résultats et conclusionNotre étude a montré que les sages-femmes étaient peu nombreuses à avoir bénéficié d’une formation pour les aider dans la prise en charge de la douleur néonatale, que la notion de douleur et sa cotation étaient subjectives et que l’échelle de douleur la plus utilisée était l’EDIN. De plus, les moyens non médicamenteux de traitement de la douleur étaient largement utilisés parmi les sages-femmes interrogées sans pouvoir conclure sur des différences de prise en charge entre les différents niveaux de maternités. La douleur étant subjective, la mise en place d’une formation auprès des soignants ainsi que des protocoles de service mis à jour régulièrement pourraient constituer des outils clés dans la prise en charge de la douleur néonatale.

Introduction: The risk of late preterm birth, between 34WG+0d and 36WG+6d, is not a current indication of antenatal steroids therapy (AST), the more effective preventive treatment of neonatal complications, because the mortality rate of these neonates is not higher than that of the term infants. Nevertheless, its large proportion and morbidity higher than full-term newborns, require an improvement in medical care.Objective: Our purpose was to demonstrate the effectiveness of antenatal steroids therapy to prevent respiratory complications on the moderate prematurity. By conducting a thorough study of the moderate prematurity’s life adaptation, we will get a better understanding of both this population and the factors influencing it. This way, populations at risk could be identified. Methods: From April to November 2017, we studied the case of 167 infants born between 34WG+0d and 36WG+6d. Two populations, with and without antenatal steroids administration, were compared. The primary endpoints were: the need for resuscitation at birth, hospitalization for respiratory distress, ventilatory support for more than 24 hours and the average duration of non-invasive ventilation.Results: 28% of our population had received an AST and 59% of the prematurity was induced. Among the population of 34WG+0d and 34WG+6d, need of using ventilatory support for more than 24 hours were impacted by AST (p=0,005). We observed a decreased need for resuscitation at birth and hospitalization for transient respiratory distress in 35WG+0d and 35WG+6d (p=0,04 and p=0,02 respectively). AST decreased the mean duration of non-invasive ventilation, and this, at all terms of the moderate prematurity (p