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Purpose: Surgical restoration of soft tissue defects often requires implantable devices. The clinical outcome of the surgery is determined by the properties inherent to the used matrix. Mesenchymal stem cells (MSC) modulate the immune processes after in vivo transplantation and their addition to matrices is associated with constructive remodeling. Herein we evaluate the potential of MSC derived from the amniotic fluid (AF-MSC), an interesting MSC source for cell therapeutic applications in the perinatal period, for immune modulation when added to a biomaterial.Methods: We implant cell free small intestinal submucosa (SIS) or SIS seeded with AF-MSC at a density of 1 × 105/cm2 subcutaneously at the abdominal wall in immune competent rats. The host immune response is evaluated at 3, 7 and 14 days postoperatively.Results: The matrix-specific or cellular characteristics are not altered after 24 h of in vitro co-culture of SIS with AF-MSC. The host immune response was not different between animals implanted with cell free or AF-MSC-seeded SIS in terms of cellular infiltration, vascularity, macrophage polarization or scaffold replacement. Profiling the mRNA expression level of inflammatory cytokines at the matrix interface shows a significant reduction in the expression of the pro-inflammatory marker Tnf-α and a trend towards lower iNos expression upon AF-MSC-seeding of the SIS matrix. Anti-inflammatory marker expression does not alter upon cell seeding of matrix implants.Conclusion: We conclude that SIS is a suitable substrate for in vitro culture of AF-MSC and fibroblasts. AF-MSC addition to SIS does not significantly modulate the host immune response after subcutaneous implantation in rats. [ABSTRACT FROM AUTHOR]

Background Clinicians increasingly require short, efficient methods for assessing distress, both in applied research and clinical settings. Most of the available questionnaires are unsuitable for busy clinical settings. The visual analogue scale (VAS) is widely but empirically used to assess perceived stress. Aims To provide evidence on two of the psychometric properties of the VAS: its discriminative sensitivity (capacity to highlight a difference between groups) and its interconcept validity (the relationship between VAS stress assessment and the assessment of different, but similar concepts). Methods Employees attending occupational health centres were randomly selected and completed the VAS and also either the Perceived Stress Scale (PSS) or the Hospital Anxiety and Depression Scale (HADS). Analyses of variance were performed to study group effects (age, sex, marital status, parental status, occupational status) on stress scores (PSS and VAS). Results In total, 763 employees participated of whom 501 completed the PSS and 262 the HADS. P-values obtained for the effects of sex, age and occupational status were lower with the VAS than with the PSS. Correlations between the VAS and the anxiety subscale, depression subscale and total score of the HADS were 0.66, 0.45 and 0.65, respectively. Other tools used to assess aspects of psychological distress are known to have similar correlations. Conclusions Our findings provide evidence that the VAS is at least as discriminating as a questionnaire when it comes to highlighting differences in stress levels between two groups, and the observed correlations with related constructs support its construct validity. [ABSTRACT FROM PUBLISHER]

Summary: We describe a case of acute chest syndrome associated with Bordetella bronchiseptica pneumonia in a child with sickle cell disease. B. bronchiseptica is recognized as an important pathogen of the respiratory tract for a large variety of animal species. This zoonotic agent has been frequently associated with chronic and recurrent infections. In humans, the bacterium acts as an opportunistic pathogen affecting mostly immunocompromised patients or those with preexisting respiratory diseases. This case and literature review provides an opportunity to discuss the risk factors, treatment, follow-up, and prevention of such zoonotic infections in the context of a lack of cross-protection of new pertussis vaccines. [ABSTRACT FROM AUTHOR]

In a packed bed with single phase liquid flow, velocity gradient and local flow direction are measured at the pore scale using tri-segmented microelectrodes flush mounted at the surface of a sphere equator area. The experimental measurements are compared to numerical predictions deduced from the solution of a 3D model based on continuity and momentum balance equations. [ABSTRACT FROM AUTHOR]

Sensing of sugar by specialized ‘glucose-inhibited’ cells helps organisms to counteract swings in their internal energy levels. Evidence from several cell types in both vertebrates and invertebrates suggests that this process involves sugar-induced stimulation of plasma membrane K+ currents. However, the molecular composition and the mechanism of activation of the underlying channel(s) remain controversial. In mouse hypothalamic neurones and neurosecretory cells of the crab Cancer borealis, glucose stimulates K+ currents displaying leak-like properties. Yet knockout of some of the candidate ‘leak’ channel subunits encoded by the KCNK gene family so far failed to abolish glucose inhibition of hypothalamic cells. Moreover, in other tissues, such as the carotid body, glucose-stimulated K+ channels appear to be not leak-like but voltage-gated, suggesting that glucose-induced inhibition may engage multiple types of K+ channels. Other mechanisms of glucose-induced inhibition, such as hyperpolarization mediated by opening of Cl− channels and depolarization block caused by closure of KATP channels have also been proposed. Here we review known ionic and pharmacological features of glucose-induced inhibition in different cell types, which may help to identify its molecular correlates. [ABSTRACT FROM AUTHOR]

Abstract: A 0.3m diameter trickle-bed reactor filled with porous alumina cylinders is used to study the influence of the catalyst loading method on liquid distribution. The study compares the performances of the dense and the sock loading methods in terms of radial liquid spreading. Measurements were performed using two wire mesh tomography devices, placed, respectively, 0.33 and 0.96m below the liquid distributor. The obtained results show that, in opposition to general agreement, sock packed beds seem to distribute liquid better than dense packed beds. This surprising result may be tentatively explained by a larger anisotropy of the dense loading. [Copyright &y& Elsevier]

Résumé Introduction En France, la consommation de substances illicites est croissante. Certaines substances peuvent être accidentellement avalées par un enfant. Nous rapportons un cas d’intoxication par de l’ecstasy, une amphétamine produite illégalement, responsable d’une symptomatologie neurologique atypique chez un nourrisson. Observation Ce nourrisson de 11 mois a présenté brutalement un état d’agitation avec révulsion oculaire et mydriase bilatérale aréactive. Toute cause cérébrale a été éliminée. La recherche de toxique a mis en évidence une intoxication aux amphétamines et MDMA (pour 3,4-méthylènedioxy-méthamphétamine). L’évolution a été favorable en 24 h. Conclusion Bien que rares, les intoxications pédiatriques par de l’ecstasy sont plus fréquentes ces dernières années du fait de sa consommation au sein des foyers. Elle expose les jeunes enfants à l’ingestion accidentelle d’un comprimé d’ecstasy. Summary Introduction In France, the use of illicit drugs is increasing and therefore accidental poisoning may occur in infants and children. We report on a case of ecstasy poisoning in an infant who presented with atypical neurological symptoms. Case report An 11-month-old infant suddenly developed agitation with eye rolling and unreactive bilateral mydriasis. All neurologic causes were excluded. The search for toxicants revealed an intoxication with an amphetamine and MDMA. Progression was favorable in 24 h. Conclusion Although rare, pediatric intoxications by ecstasy have become more common in recent years, due to its consumption within households, exposing young children and infants to accidental ingestion of a tablet of ecstasy. [ABSTRACT FROM AUTHOR]

An electrodiffusion measurement system has been developed and used in a packed bed with single phase liquid flow. It is based on a tri-segmented microelectrode flush mounted at the surface of an Altuglass sphere equator area. Four of such probes are placed in lozenge form in the packed bed thus constituting a pore where the measurements were carried out. Each probe is equipped with a rotating system which allows the probe to turn around its vertical axis and consequently allows the microelectrode to cover all azimuthal positions. The tri-segmented microelecrodes are first calibrated in a separate experimental setup where the hydrodynamics is controlled and then placed in the packed bed. The results presented concern mainly the velocity gradient and local flow direction measurements. [ABSTRACT FROM AUTHOR]

A wire-mesh tomography device was used to study the liquid saturation at 78 points covering the cross-sectional area of a 0.30m diameter trickle bed reactor. Measurements in the pulsing flow near the transition were done for glass beads and alumina cylinders using air and water as fluids. Local liquid saturation measurements allow identification of flow regime and pulse frequency for each of the 78 points considered. To the best of the authors’ knowledge this is the first time that such local measurements are done for the complete sectional area of a trickle bed reactor. Flow rate conditions at which different flow regimes coexist at the same horizontal plane of the column were identified. A remarkable influence of the initial liquid distribution on the observed flow regime was also observed. [Copyright &y& Elsevier]

Abstract: Introduction: K+ channels allow the passive and selective transport of K+ ions through the membranes. They control K+ homeostasis, neuronal and muscular excitabilities, and neurotransmitter and hormone release. Exegesis: K+ channels are composed of pore-forming subunits associated with regulatory subunits. Many different K+ channels have been identified. Conclusion: This diversity is stressed by the growing number of genetic and acquired diseases associated with these channels. [Copyright &y& Elsevier]

This paper carries on the investigation of the non-unitary su(2)−1/2 WZW model. An essential tool in our first work on this topic was a free-field representation, based on a c=−2 ηξ ghost system, and a Lorentzian boson. It turns out that there are several ‘versions’ of the ηξ system, allowing different su(2)−1/2 theories. This is explored here in details. In more technical terms, we consider extensions (in the c=−2 language) from the small to the large algebra representation and, in a further step, to the full symplectic fermion theory. In each case, the results are expressed in terms of su(2)−1/2 representations. At the first new layer (large algebra), continuous representations appear which are interpreted in terms of relaxed modules. At the second step (symplectic formulation), we recover a logarithmic theory with its characteristic signature, the occurrence of indecomposable representations. To determine whether any of these three versions of the su(2)−1/2 WZW is well defined, one conventionally requires the construction of a modular invariant. This issue, however, is plagued with various difficulties, as we discuss. [Copyright &y& Elsevier]

The hair cell, the sensory receptor of the internal ear, releases neurotransmitter at presynaptic active zones studding its basolateral membrane surface. Examination of hair cells by loose-seal patch recording demonstrated that each active zone bears a cluster of voltage-gated Calcium ions (Cav) channels and Ca ions activated potassium ions (KCa) channels. When Cav channels are activated by a hair cell's depolarization in response to acoustical stimulation, the resultant Ca ions influx not only triggers synaptic-vesicle release but also opens KCa channels. The efflux of K ion through these channels causes a rapid repolarization that plays a key role in the electrical oscillation that tunes some hair cells and in fast inhibitory synaptic transmission.

The bosonic βγ ghost system has long been used in formal constructions of conformal field theory. It has become important in its own right in the last few years, as a building block of field theory approaches to disordered systems, and as a simple representative—due in part to its underlying su(2)−1/2 structure—of non-unitary conformal field theories. We provide in this paper the first complete, physical, analysis of this βγ system, and uncover a number of striking features. We show, in particular, that the spectrum involves an infinite number of fields with arbitrarily large negative dimensions. These fields have their origin in a twisted sector of the theory, and have a direct relationship with spectrally flowed representations in the underlying su(2)−1/2 theory. We discuss the spectral flow in the context of the operator algebra and fusion rules, and provide a re-interpretation of the modular invariant consistent with the spectrum. [Copyright &y& Elsevier]

This paper presents experimental measurements and theoretical predictions of the velocity gradient in a fixed-bed reactor with single phase liquid flow. The local measurements are carried out by means of microelectrodes embedded in the packing of the bed, whereas the corresponding predictions are based on the surface renewal model. The fluid elements age distributions, needed in the surface renewal model, were determined using the variable-interval time-averaging (VITA) method. The parameters of VITA method, i.e. local interval time-averaging length a and threshold level k, were optimally selected and are equal to 3TC (TC is the integral time deduced from auto-correlation functions) and 0.9, respectively. It was shown that the surface renewal model is appropriate for predictions at high liquid flow rates, corresponding to a flow that behaves like a turbulent flow. Moreover, it was shown that with only one velocity gradient signal measurement, both experimental and theoretical values are obtained for a specified flow rate. The average value of the signal provides the experimental measurement, whereas its fluctuating part yields the corresponding theoretical prediction. [Copyright &y& Elsevier]

Background The visual analogue scale (VAS) is empirically used by occupational physicians to assess stress but very few studies have been published about its quantitative validation.Aims To assess the external validity of the VAS for the assessment of stress in the clinical occupational health setting by comparing its scores with the Perceived Stress Scale (PSS) of Cohen.Methods An anonymous self-completed questionnaire (PSS14) and the VAS were filled in by a random sample of 360 workers from several occupational health centres.Results No difference between the mean scores of PSS14 and stress VAS was found. The equation of the linear regression was ‘VAS score = −0.18 + 1008 × PSS14 score’. A VAS score of 7.0 was identified as having the best sensitivity/specificity ratio (0.74 and 0.93, respectively) for identifying those with ‘high stress’ using the PSS cut-off score of 7.2, using a receiver operator curve approach.Conclusions Our results support an acceptable agreement between the two tests, meaning that the two tools assess the same psychological construct. The good sensitivity/specificity ratio and the area under the curve close to 1 provide evidence that a VAS is suitable to help the occupational physician detect a high level of stress. The use of a VAS for stress assessment seems to be meaningful, suitable and useful for occupational physicians. [ABSTRACT FROM PUBLISHER]

Nonbacterial purpura fulminans (PF) is rare, usually follows viral infection in young children, and is characterized by specific coagulation disorders, requiring specific therapy. Following a transient rash, a 2-year-old previously healthy girl developed PF without haemodynamic impairment. Laboratory data revealed disseminated intravascular coagulation and a severe transient protein S deficiency. Antiprotein S autoantibodies and active human herpesvirus-6 (HHV6) replication were demonstrated. Purpuric skin lesions spread very rapidly despite broad-spectrum antibiotics and right leg amputation. Plasmapheresis and intravenous immunoglobulins gave complete clinical recovery and normalization of protein S level within 10 days, with progressive clearance of antiprotein S autoantibodies. Transient severe protein S deficiencies have previously been reported in patients with nonbacterial PF, usually after varicella infection. This is the first documented case of PF after HHV6 infection. [ABSTRACT FROM AUTHOR]

Objectifs: Définir les facteurs pronostiques de survie chez les nouveau-nés atteints de chylothorax congénital. Patients et Méthodes: Étude rétrospective mono-centrique des 29 nouveau-nés hospitalisés en réanimation pour chylothorax congénital entre 1999 et 2009. Recherche de facteurs de risque de décès en uni-varié par test de Fisher ou de Mann-Whitney. Résultats: 11/29 enfants sont décédés (38 %), 6 d’insuffisance respiratoire, 3 d’insuffisance rénale organique et 2 de cause mixte. Sur 4 autopsies, 2 ont retrouvé une hypoplasie pulmonaire, 1 des lymphangiectasies pulmonaires. Les facteurs de risque de décès sont : l’importance de la prématurité (p = 0,039), l’absence de drainage anténatal (64 % de décès versus 22 % ; p = 0,048), la présence d’une anasarque postnatale (75 % de décès versus 24 % ; p = 0,028), la naissance en état de mort apparente (p = 0,01), la nécessité d’une évacuation pleurale postnatale (p = 0,019), l’association à une pathologie générale (83 % de décès versus 26 % ; p = 0,018). Conclusions: La sévérité du chylothorax congénital est principalement liée à son association avec une insuffisance respiratoire constitutionnelle, persistant malgré un bon contrôle de l’épanchement pleural postnatal. [ABSTRACT FROM AUTHOR]

Studies thrombocytopenia during acute Plasmodium falciparum malaria in 64 traveller children from Paris, France, 85 children from Dakar, Senegal, with an intermittent exposure and 81 children from Libreville, Gabon with a perennial exposure. Presence of initial thrombocytopenia in 43-58 percent of children with P. falciparum malaria; Tendency of low parasitemia to lead to misdiagnosis.

Background: Few melanoma cases are reported in individuals with intellectual disability (ID), and prognostic factors at diagnosis are unknown in this population. This work was designed to investigate whether prognostic factors at diagnostic are different in patients with ID compared with a general population. Methods: Melanoma cases retrieved from Hérault's Tumour Registry (HTR) from 1995 to 2015 were cross‐referenced against a list of adult patients with ID, living in Hérault. Major prognostic factors were compared with those in non‐ID melanoma patients included in HTR and in patients followed by Montpellier University Hospital and included in the Réseau pour la Recherche et l'Investigation Clinique sur le Mélanome (RIC‐Mel) database. Results: Ten melanoma cases in individuals with ID were identified and compared with 3804 non‐ID melanoma cases in HTR and 1024 non‐ID melanoma cases included in RIC‐Mel. Mean Breslow thickness at diagnosis was 4.6 mm in melanoma cases among those with ID versus 1.89 mm in HTR (P = 0.109) and 2.36 mm in RIC‐Mel (P = 0.156). Stage at diagnosis was superior to stage IIB in 42.9% of ID cases versus 11.4% of non‐ID cases in HTR (P < 0.05) and 8.5% in RIC‐Mel (P < 0.05). Conclusions: Melanomas in patients with ID had less favourable prognostic factors at diagnosis, including higher Breslow thickness and more advanced stage, than melanomas in non‐ID patients. These adverse prognostic factors indicate a later diagnosis in this population, leading to a poorer prognosis. This work underlines the need to improve melanoma screening among individuals with ID. [ABSTRACT FROM AUTHOR]

Mucormycosis, an emerging fungal infection in solid organ transplant patients, is mostly located in rhino-orbito-cerebral, pulmonary, and cutaneous areas, or disseminated with poor prognosis. A 4-year-old girl with chronic intestinal pseudo-obstruction syndrome underwent a modified multivisceral transplantation, including half of the stomach, the duodeno-pancreas, the small bowel, and the right colon. On postoperative day 5, a digestive perforation was suspected. Surgical exploration found a small necrotic area on the native stomach, which was externally drained. The next day, massive gastric bleeding occurred. During the emergency laparotomy, 2 hemorrhagic ulcers were found and resected from the transplanted stomach. Pathology and fungal culture showed mucormycosis caused by Lichtheimia (formerly Absidia) ramosa in both the transplanted and native stomach. High-dose intravenous liposomal amphotericin B was immediately started. No other site of fungal infection was found. The child recovered, and 3 years after transplantation, is alive and well, off parenteral nutrition. The originality of this case is the very early presentation after transplantation, the unusual site, and the complete recovery after rapid medico-surgical management. The origin of the fungus and treatment are discussed. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the general multimaterial formulation of Kashiwa and Rauenzahn [1] is used to derive an appropriate hydrodynamic model for a trickle-bed reactor operating under trickling flow conditions. Using some realistic assumptions, the resulting model consists of two equations in two unknowns, i.e., liquid volume fraction and pressure. Moreover, the equations exhibit elliptic (pressure) and hyperbolic (volume fraction) behaviours, which require the use of different numerical methods in order to correctly handle these different numerical behaviours. Thus, the finite volume method, the Crank–Nicholson scheme and the second order Godunov''s method combined with the solution of Riemann problem were implemented. The numerical results of pressure drops derived from the model solution are shown to be in good agreement with the values measured in the same operating conditions or previously published in the literature. [Copyright &y& Elsevier]

The aim of this study was to describe severe forms of novel coronavirus disease 2019 in children, including patient characteristics, clinical, laboratory, and imaging findings, as well as the disease management and outcomes. This was a retrospective, single-center, observational study conducted in a pediatric intensive and high-dependency care unit (PICU, HDU) in an urban hospital in Paris. All patients, aged from 1 month to 18 years, admitted for confirmed or highly suspected SARS-CoV-2 were included. We analyzed the data of 27 children. Comorbidities (n = 19, 70%) were mainly neurological (n = 7), respiratory, (n = 4), or sickle cell disease (n = 4). SARS-CoV-2 PCR results were positive in 24 children (nasopharyngeal swabs). The three remaining children had a chest CT scan consistent with COVID-19. Respiratory involvement was observed in 24 patients (89%). Supportive treatments were invasive mechanical ventilation (n = 9), catecholamine (n = 4), erythropheresis (n = 4), renal replacement therapy (n = 1), and extracorporeal membrane oxygenation (n = 1). Five children died, of whom three were without past medical history. This study highlighted the large spectrum of clinical presentation and time course of disease progression as well as the non-negligible occurrence of pediatric life-threatening and fatal cases of COVID-19 mostly in patients with comorbidities. Additional laboratory investigations are needed to further analyze the mechanism underlying the variability of SARS-Cov-2 pathogenicity in children. [ABSTRACT FROM AUTHOR]

Neurological involvement is frequent in inherited metabolic disease of the intoxication type. Hyperammonemic coma related to these diseases may cause severe neurological sequelae. Early optimal treatment is mandatory combining metabolite scavengers (MS) and sometimes continuous veno-venous hemodialysis (CVVHD). We aimed to describe the therapeutic management of hyperammonemia in neonates upon diagnosis of their metabolic disease and to compare neonates managed with MS alone or with both MS and CVVHD. We conducted a retrospective study including all neonates admitted for initial hyperammonemia to the pediatric intensive care unit of a Reference Center of Inherited Metabolic Diseases, between 2001 and 2012. The study included 35 neonates. Before admission, MS were initiated for 11 neonates. At admission, the median ammonia levels were 391 μmol/L and were significantly lower in neonates who received MS before admission. At admission, ammonia levels were 644 μmol/L in dialyzed and 283 μmol/L in non-dialyzed neonates. The median time to reach a 50% decrease of the initial ammonia levels was significantly shorter in dialyzed neonates; however, the normalization of ammonia levels was similar between dialyzed and non-dialyzed neonates. Hemodynamic disorders were more frequent in dialyzed neonates. MS represent an effective treatment for hyperammonemia and should be available in all pediatric units to avoid the need for CVVHD. Although CVVHD enhances the kinetics of toxic metabolite decrease, it is associated with adverse hemodynamic effects. [ABSTRACT FROM AUTHOR]

Staphylococcal scalded skin syndrome (SSSS) is caused by the exfoliative toxins (ET) A and B produced by some I Staphylococcus aureus i ( I S. aureus i ) strains. Paediatric SSSS is most commonly seen between 6 months and 5 years of age.[1] Around 90% of term infants have anti-ETA antibodies in their umbilical blood.[1] Neonatal SSSS results classically from inappropriate umbilical care or circumcision procedures. The use of feeding bottles was significantly more frequent among patients with infectious mastitis [approximately 4.10 times (OR: 4.10) higher].[5] I S. aureus, S. epidermidis i and I Corynebacteria i have been identified as the predominant aetiological agents in acute, subacute and granulomatous mastitis, respectively. [Extracted from the article]

Aim Identifying early clinical and biological factors associated with severe forms of postdiarrheal hemolytic uremic syndrome (D + HUS) that may help practitioners determine appropriate treatment. Methods This retrospective study was conducted in 49 children with D + HUS between 2001 and 2011. Severe forms were defined as occurrence of one of the following conditions: death, major neurological involvement, cardiovascular involvement, and/or the presence of sequelae (neurological, cardiovascular, pancreatic, or renal). Results During the acute phase, 35 children exhibited at least one type of extrarenal involvement including 13 severe forms with a median delayed occurrence after admission of 4.5 days (range: 1–8) for comatose children and 5 days (range: 2–6) for cardiovascular involvement; 32 children required dialysis and three died. In multivariate analysis, (i) major neurological involvement ( n = 13), (ii) dialysis ( n = 32), and (iii) sequelae ( n = 12) were associated with (i) fever during the prodromal phase requiring dialysis at admission, (ii) C-reactive protein level (CRP) > 22 mg/L at admission, and (iii) major neurological involvement and a white blood cell count (WBC) > 20 × 10 3 /mm 3 during the acute stage, respectively. Conclusions D + HUS is a multiorgan disease with a delayed occurrence of life-threatening extrarenal organ involvement. Severe forms appear to be associated with early biological and clinical inflammatory parameters. [ABSTRACT FROM AUTHOR]

Résumé L’œdème aigu hémorragique du nourrisson (OAHN) est une vascularite rare et bénigne survenant chez des nourrissons de 4 à 24 mois. Les lésions cutanées, prenant parfois l’aspect d’un purpura ecchymotique ou en nappe, peuvent faire évoquer le diagnostic de purpura fulminans lorsqu’une fièvre y est associée et entraîner alors la mise en route d’une antibiothérapie. Nous rapportons le cas d’un nourrisson de 7 mois dont la présentation clinique initiale d’OAHN a fait suspecter un purpura fulminans. L’évolution rapide des lésions a fait instaurer une antibiothérapie par céfotaxime et amikacine. Le diagnostic d’OAHN a été porté le lendemain devant l’aspect des lésions cutanées, la stabilité hémodynamique de l’enfant et la négativité du bilan bactériologique. Un entérovirus (Coxsackie virus B5) a été mis en évidence secondairement par réaction de polymérisation en chaîne spécifique (PCR) dans le liquide céphalorachidien. Après arrêt de l’antibiothérapie, l’évolution a été spontanément favorable. L’imputabilité de l’entérovirus dans le déclenchement de cet OAHN est discutée. Summary Acute hemorrhagic edema of infancy is a rare but benign vasculitis occurring in infants aged from 4 to 24 months. Skin lesions can take various forms, including extensive hemorrhagic purpura, and can therefore be mistaken for purpura fulminans if associated with fever, which leads to initiating broad-spectrum antibiotic treatment. In the present case, we describe a 7-month-old boy with acute hemorrhagic edema of infancy and rapidly extensive purpura lesions that led to intravenous cefotaxime and amikacin treatment. Diagnosis was made on the next day by a dermatologist, based on the typical aspect of skin lesions, hemodynamic stability, and negative bacteriological samples. Coxsackie virus B5, a pathogenic enterovirus, was found by specific PCR in cerebrospinal fluid. The outcome was spontaneously favorable after discontinuation of antibiotics on day 2. We discuss the imputability of the enterovirus in triggering this case of acute hemorrhagic edema of infancy. [ABSTRACT FROM AUTHOR]

Optical imaging of retinal intrinsic signals is a relatively new method that provides spatiotemporal patterns of retinal activity through activity-dependent changes in light reflectance of the retina. The exact physiological mechanisms at the origin of retinal intrinsic signals are poorly understood and there are significant inter-species differences in their characteristics and cellular origins. In this study, we re-examined this issue through pharmacological dissection of retinal intrinsic signals in the rabbit with simultaneous ERG recordings. Retinal intrinsic signals faithfully reflected retinal activity as their amplitude was strongly associated with stimulation intensity (r2=0.85). Further, a strong linear relation was found using linear regression (r2=0.98) between retinal intrinsic signal amplitude and the ERG b wave, which suggests common cellular origins. Intravitreal injections of pharmacological agents were performed to isolate the activity of the retina's major cell types. Retinal intrinsic signals were abolished when the photoreceptors' activity was isolated with aspartate, indicative that they are not at the origin of this signal. A small but significant decrease in intrinsic response (20%) was observed when ganglion and amacrine cells' activity was inhibited by TTX injections. The remaining intrinsic responses were abolished in a dose-dependent manner through the inhibition of ON-bipolar cells by APB. Our results indicate that, in rabbits, retinal intrinsic signals reflect stimulation intensity and originate from the inner retina with a major contribution of bipolar cells and a minor one from ganglion or amacrine cells. [ABSTRACT FROM AUTHOR]

Neuroligin 1 (NLGN1) is a postsynaptic adhesion molecule that determines N-methyl- d -aspartate receptor (NMDAR) function and cellular localization. Our recent work showed that Nlgn1 knockout (KO) mice cannot sustain neuronal activity occurring during wakefulness for a prolonged period of time. Since NMDAR-dependent neuronal activity drives an important vascular response, we used multispectral optical imaging to determine if the hemodynamic response to neuronal stimulation is modified in Nlgn1 KO mice. We observed that Nlgn1 KO mice show a 10% lower response rate to forepaw electrical stimulation compared to wild-type (WT) and heterozygote (HET) littermates on both the contra- and ipsilateral sides of the somatosensory cortex. Moreover, Nlgn1 mutant mice showed an earlier oxyhemoglobin peak response that tended to return to baseline faster than in WT mice. Analysis of the time course of the hemodynamic response also showed that HET mice express a faster dynamics of cerebrovascular response in comparison to WT. Taken together, these data are indicative of an altered immediate response of the brain to peripheral stimulation in Nlgn1 KO mice, and suggest a role for NLGN1 in the regulation of cerebrovascular responses. [ABSTRACT FROM AUTHOR]

Résumé: Introduction et objectifs: Préciser la connaissance des soignants de réanimation pédiatrique (RP) sur la loi Léonetti, connaître leurs opinions vis-à-vis des décisions de limitation ou arrêt des thérapeutiques (LAT) et leur ressenti sur la façon dont ces décisions ont été prises et appliquées. Matériel et méthode: Étude multicentrique par questionnaire durant le dernier trimestre 2010. Résultats: Mille cinq personnels paramédicaux et 334 médecins ont répondu. Plus de 85 % avaient une bonne connaissance des grands principes de la Loi. Plus de 80 % des soignants adhéraient aux LAT lorsqu’elles concernaient une suppléance respiratoire, hémodynamique ou rénale. En revanche, l’arrêt de la nutrition et de l’hydratation artificielle était récusé ou générait des réticences chez la majorité des répondants. Alors que la délibération collégiale était estimée indispensable par l’ensemble des soignants, les personnels paramédicaux trouvaient beaucoup plus souvent que les médecins que leur implication réelle était insuffisante. La qualité des fins de vie était jugée très favorablement par les soignants. Cependant, les réponses concernant les modalités d’application des LAT suggèrent des interprétations très différentes de la Loi : certains respectaient les principes des soins palliatifs tels qu’ils sont définis par le code de santé publique, alors que 40 % des médecins et 64 % des soignants jugeaient ű acceptable Ƈ de provoquer un décès si la décision était collégiale. Conclusion: Cette étude est la première à montrer que les soignants des unités de RP françaises ont une bonne connaissance de la loi Léonetti. Il persiste cependant des divergences importantes sur les pratiques jugées légalement acceptables en fin de vie. [ABSTRACT FROM AUTHOR]

L’infection à Parvovirus B19 (PB19) est une maladie infantile bénigne et fréquente. De rares cas de myocardites fatales ont été rapportés, dont la physiopathologie demeure incertaine. Nous rapportons deux nouveaux cas de myocardites fulminantes à PB 19 : 2 enfants sains qui, quelques jours suivant l’apparition de symptômes évoquant une infection banale à PB19, sont brutalement décédés d’incompétence myocardique. Le virus a été isolé dans le sérum des 2 patients par PCR ; les sérologies confirmaient l’infection récente à PB 19. L’analyse histologique post-mortem complète du tissu cardiaque a permis le diagnostic de myocardite fulminante en montrant un infiltrat inflammatoire majeur. Ces constatations sont en accord avec les hypothèses actuelles qui écartent un rôle cytopathogène du virus et privilégient une atteinte indirecte du myocarde. La myocardite aigue grave à PB19 de l’enfant, probablement de nature inflammatoire ou post-infectieuse, serait due à une dysrégulation de la réponse immune de l’hôte : elle serait disproportionnée et responsable de lésions myocardiques massives. Aucun critère clinique ne peut malheureusement à l’heure actuelle prédire l’évolution bien que très rarement dramatique de cette infection banale. [ABSTRACT FROM AUTHOR]

Summary: Introduction: Although rare, salicylate intoxication through the skin should not be ignored as it can be severely life-threatening. We describe an original case of accidental poisoning with salicylates topically applied to the scalp of a 6-week-old infant. Clinical report: A 6-week-old infant, with no prior history, was admitted to the pediatric intensive care unit for treatment of severe disorders of consciousness associated with significant tachypnea. Laboratory results revealed metabolic acidosis with elevated anion gap, ketonuria, and normal glycemia. Initial assessment ruled out the hypothesis of accidental ingestion of salicylates. However, the presence of salicylic acid derivatives in organic acid chromatography, confirmed by plasma salicylate levels at 580mg/L, ultimately re-established the diagnosis. Further inquiry retrospectively highlighted the prolonged topical application in occlusion (3 days) of an extemporaneous preparation containing 23% salicylic acid on the scalp. The course after urine alkalinization was rapidly favorable without sequelae. Comment and conclusions: Salicylate intoxication is potentially lethal, particularly in infants under 12 months of age. The vast majority of these intoxications result from accidental ingestion. The present observation underscores the original and undescribed risk of intoxication due to a localized application to the scalp. In the presence of warning symptoms, salicylate poisoning should be investigated, including topical application of salicylic acid, even if localized. Careful attention should be paid to following the indications of use of this product in terms of concentration, characteristics of the infant, and exposed skin. The use of extended topical application of salicylic acid in concentrations greater than 3% should be avoided. [Copyright &y& Elsevier]

Abstract: Since the Kalman filter and Monte Carlo techniques, much theoretical work has been put into the development of signal deconvolution tools. Among recent developments taking place in neuroscience are Dynamic Expectation Maximization, Generalized Filtering and the Cubature Kalman Filter. While there are exciting prospects to use these tools for Dynamic Causal Modeling and other analyses of networks, there has been comparatively little work to validate the algorithms on controlled experimental data. In this work, the latest evolution of these tools, the square-root cubature Kalman smoother (SCKS), is tested for its effectiveness on multimodal neurovascular data. Multispectral intrinsic optical imaging and electrophysiological measurements of Wistar rats are used in combination with somatosensory stimulation. The Buxton–Friston (B–F) balloon model is then deconvolved with the SCKS algorithm to obtain the estimated neuronal inputs u(t) from the hemodynamic measurements (flow, oxy- and deoxygenated hemoglobin). Results: The estimated neuronal inputs are compared to the stimulation protocol and a sensitivity and specificity analysis is carried out. SCKS succeeds in recovering most of the stimulations. Next, the estimated inputs are compared to actual measures of neuronal activity: local field potentials (LFPs) and multiunit activity (MUA). Good sensitivity of the technique is obtained with both LFPs and MUA over the whole recordings, with the area of the ROC curves favoring LFPs. A weak correlation between SCKS estimated inputs and LFPs is found outside stimulation periods, significant at one standard deviation. Finally, the accuracy of state reconstructions is studied and SCKS reconstructed states are highly concordant with measured states. [Copyright &y& Elsevier]

Healthy aging is characterized by a number of changes on brain structure and function. Several neuroimaging studies have shown an age-related reduction in hemispheric asymmetry on various cognitive tasks, a phenomenon captured by Cabeza (2002) in the Hemispheric Asymmetry Reduction in Older Adults (HAROLD) model. Although this phenomenon is supported by a range of neuroimaging data on memory and inhibitory processes, there is little evidence concerning changes in hemispheric asymmetry for language processing, and particularly word retrieval, which is assessed with verbal fluency task (VFT). This study aimed to investigate the age-related changes in cerebral oxygenation in the prefrontal cortex for both letter and category VFT, varying the complexity of the criteria (i.e., degree of productivity) and using near-infrared spectroscopy (NIRS). Sixteen younger and 16 older adults participated in this study. For both VF conditions, participants were instructed to pronounce as many nouns as possible as a function of high-productivity (e.g., 'animals' or 'L') or low-productivity (e.g., 'flowers' or 'V') criteria. Behavioral data (i.e., accuracy responses) showed comparable performance in younger and older adults for both VF conditions. However, NIRS data showed more reduced activation (i.e., significantly reduced increase in [O(2)Hb] and reduced decrease in [HHb]) in older than younger adults for both VFT. In addition, a bilateral effect was found for both groups, suggesting that VFT requires both executive and language functions. The results are discussed in the context of the current theories of aging.Copyright © 2012 by Elsevier Inc. [ABSTRACT FROM AUTHOR]

Relatively few studies have analyzed the mechanisms underlying the cognitive changes that affect language in the elderly, and fewer have done so for narrative discourse. The goal of this study was to explore the neurofunctional changes associated with aging for different components of narrative discourse. Functional near-infrared spectroscopy (fNIRS) and behavioral data on 10 younger adults and 10 healthy elderly participants were collected. Ten younger adults in a non-proficient second language condition were included to explore the possibility that the age-related neurofunctional reorganization partly expresses demanding resource allocation. Results show within- and across-hemispheric differences in the neurofunctional pattern of activation in the older participants with reference to the younger ones, partially shared with the low-proficiency young adults, providing support for the recognized mechanisms underlying neural reserve and compensation. fNIRS was shown to be appropriate for studying the age-related neurofunctional reorganization of complex cognitive abilities.Copyright © 2012 by Elsevier Inc. [ABSTRACT FROM AUTHOR]

Abstract: Neuronal, vascular and metabolic factors result in a deterioration of the cerebral hemodynamic response with age. The interpretation of neuroimaging studies in the context of aging is rendered difficult due to the challenge in untangling the composite effect of these modifications. In this work we integrate multimodal optical imaging in biophysical models to investigate vascular and metabolic changes occurring in aging. Multispectral intrinsic optical imaging of an animal model of healthy aging, the LOU/c rat, is used in combination with somatosensory stimulation to study the modifications of the hemodynamic response with increasing age. Results are fitted with three macroscopic biophysical models to extract parameters, providing a phenomenological description of vascular and metabolic changes. Our results show that 1) biophysical parameters are estimable from multimodal data and 2) parameter estimates in this population change with aging. [Copyright &y& Elsevier]

Abstract: The LOU/c rat is an inbred strain considered a model of healthy aging. It exhibits a longer free disease lifespan and a low adiposity throughout life. While this animal model has been shown to maintain eating behavior and neuroendocrine, metabolic and cognitive functions with age, no study has yet investigated vascular correlates in this model of healthy aging. In the present work, multispectral optical imaging was used to investigate the hemodynamic response in the somatosensory cortex of LOU/c rats following forepaw stimulation in three age groups, 4, 24 and 40months. Results indicate reduced hemodynamic responses in the contralateral somatosensory cortex between young (4months) and older groups following stimulation. This decrease was associated with an increase in the spatial extent of activation. The ipsilateral response did not change with aging leading to decreased laterality. Estimations of the relative change in the local cerebral metabolic rate of oxygen during stimulation based on multimodal data showed no significant change with age. The exponent describing the relation between blood volume and blood flow changes, Grubb''s parameter, did display a significant change with age which may suggest vessel compliance modifications. This work finds its relevance in recent findings underlying the importance of vascular changes with aging and its impact on neurodegenerative disease. [Copyright &y& Elsevier]

Abstract: Simultaneous recordings of Electro-EncephaloGraphy (EEG) with Near InfraRed Spectroscopy (NIRS) allow measuring hemodynamic changes (changes in the concentration of oxy- and deoxyhemoglobin) at the time of epileptic discharges detected on scalp EEG. Two NIRS detection methods based on the General Linear Model (GLM) respectively in the time domain and in the time–frequency domain are investigated in this study using realistic simulations of spontaneous interictal epileptic activity. We evaluated the sensitivity at different Signal to Noise Ratios (SNR), the effect of either a large or a small number of discharges and the impact of model misspecification (e.g. omission or false detection of epileptic discharges). We also explored the effect on the estimation of key parameters, which set the model order. Simulations showed that both methods become inaccurate in lower SNR conditions, leading to many false positive detections. However, the time–frequency estimator showed better performance than the time-domain one. Key parameters for each algorithm were identified and results suggest to model confounds in the GLM differently for oxy- and deoxyhemoglobin. We also demonstrated that an inaccurate marking of epileptic events has a small impact on the detection statistics whereas an inaccurate specification of the hemodynamic response function delay decreases drastically the detection abilities. Finally, we illustrated the two methods on clinical EEG/NIRS data of one patient with focal epilepsy, showing an increase of regional Cerebral Blood Volume (rCBV) spatially concordant with the presumed epileptogenic focus. [Copyright &y& Elsevier]

Abstract: Diffuse optical imaging uses light to provide a surrogate measure of neuronal activation through the hemodynamic responses. The relative low absorption of near-infrared light enables measurements of hemoglobin changes at depths reaching the first centimeter of the cortex. The rapid rate of acquisition and the access to both oxy and deoxy-hemoglobin leads to new challenges when trying to uncouple physiology from the signal of interest. In particular, recent work provided evidence of the presence of a 1/f noise structure in optical signals and showed that a general linear model based on wavelets can be used to decorrelate the structured noise and provide a superior estimator of response amplitude when compared with conventional techniques. In this work the wavelet techniques are extended to recover the full temporal shape of the hemodynamic responses. A comparison with other models is provided as well as a case study on finger-tapping data. [Copyright &y& Elsevier]

Abstract: In the visual system, neurons with similar functional properties such as orientation and direction selectivity are clustered together to form modules. Optical imaging recordings in combination with episodic paradigms have been previously used to estimate direction selectivity, a fundamental property of visual neurons. The major drawback of the episodic approach is that the extraction of the signal from various forms of physiological noise is difficult, leading to a poor estimation of direction. Recent work, based on periodic stimulation and Fourier decomposition improved the extraction of periodic stimulus responses from noise and thus, reduced the recording time considerably. Given the success of this new paradigm in mapping orientation, the present study evaluated its reliability to measure direction selectivity in the visual cortex of anesthetized cats. Here, a model that exploits the harmonics of the Fourier decomposition is proposed where the first harmonic is related to direction responses, and the second to orientation. As expected, the first harmonic was absent when a static stimulus was presented. Contrarily, the first harmonic was present when moving stimuli were presented and the amplitude was greater with random dots kinematograms than with drifting gratings. The phase of the first harmonic showed a good agreement with direction preference measured by episodic paradigm. The ratio of the first/the second harmonic amplitude, related to a direction index, was weaker in fracture. It was also weaker in areas of the ventral pathway (areas 17 and 21a) where direction selectivity is known to be reduced. These results indicate that a periodic paradigm can be easily used to measure specific parameters in optical signals, particularly in situations when short acquisition periods are needed. [Copyright &y& Elsevier]

Abstract: Due to its non-invasive nature and low cost, diffuse optical imaging (DOI) is becoming a commonly used technique to assess functional activation in the brain. When imaging with DOI, two major issues arise in the data analysis: (i) the separation of noise of physiological origin and the recovery of the functional response; (ii) the tomographic image reconstruction problem. This paper focuses on the first issue. Although the general linear model (GLM) has been extensively used in functional magnetic resonance imaging (fMRI), DOI has mostly relied on filtering and averaging of raw data to recover brain functional activation. This is mainly due to the high temporal resolution of DOI which implies a new design of the drift basis modelling physiology. In this paper, we provide (i) a filtering method based on cosine functions that is more adapted than standard averaging techniques for DOI specifically; (ii) a new mode-locking technique to recover small signals and locate them temporally with high precision (shift method). Results on real data show the capability of the shift method to retrieve HbR and HbO2 peak locations. [Copyright &y& Elsevier]

The β subunits of voltage-gated Ca[sup 2+] channels are known to be regulators of the channels' gating properties. Here we report a striking additional function of a β subunit. Screening of chicken cochlear and brain cDNA libraries identified β[sub 4c], a short splice variant of the β[sub 4] subunit. Although β[sub 4c] occurs together with the longer isoforms β[sub 4a] or β[sub 4b] in the brain, eye, heart, and lung, the cochlea expresses exclusively β[sub 4c]. The association of β[sub 4c] with the Ca[sup 2+]-channel α[sub 1] subunit has slight but significant effects on the kinetics of channel activation and inactivation. Yeast two-hybrid and biochemical assays revealed that β[sub 4c] interacts directly with the chromo shadow domain of chromobox protein 2/heterochromatin protein 1γ, (CHCB2/HP1γ), a nuclear protein involved in gene silencing and transcriptional regulation. Coexpression of this protein specifically recruits β[sub 4c] to the nuclei of mammalian cells. Furthermore, β[sub 4c] but not β[sub 4a] dramatically attenuates the genesilencing activity of chromobox protein 2/heterochromatin protein 1γ. The β[sub 4c] subunit is therefore a multifunctional protein that not only constitutes a portion of the Ca[sup 2+] channel but also regulates gene transcription. [ABSTRACT FROM AUTHOR]

Ca2+ influx through voltage-gated channels initiates the exocytotic fusion of synaptic vesicles to the plasma membrane. Here we show that RIM binding proteins (RBPs), which associate with Ca2+ channels in hair cells, photoreceptors, and neurons, interact with α1D (L type) and α1B (N type) Ca2+ channel subunits. RBPs contain three Src homology 3 domains that bind to proline-rich motifs in α1 subunits and Rab3-interacting molecules (RIMs). Overexpression in PC12 cells of fusion proteins that suppress the interactions of RBPs with RIMs and α1 augments the exocytosis triggered by depolarization. RBPs may regulate the strength of synaptic transmission by creating a functional link between the synaptic-vesicle tethering apparatus, which includes RIMs and Rab3, and the fusion machinery, which includes Ca2+ channels and the SNARE complex. [Copyright &y& Elsevier]

Abstract: We evaluated 131 patients (6 months–14 years) who experienced 21 deaths before listing, 11 continuing on the waiting list, 38 well on home parenteral nutrition, 6 off parenteral nutrition and 59 transplanted (20 girls) aged 2.5 to 15 years, (18 >7 years). They received cadaveric isolated intestine (ITx, n = 31) or liver-small bowel (LITx, n = 32), including right colon (n = 43; 23 LITx) for short bowel (n = 19), enteropathy (n = 20), Hirschsprung (n = 14), or pseudo-obstruction (n = 6). Treatment included tacrolimus, steroids, azathioprine, or interleukin-2 blockers. After 6 months to 10.5 years, the patient and graft survivals were 75% and 54%. Sixteen patients (10 LITx) died within 3 months from surgery (n = 3), bacterial (n = 5) or fungal (n = 6) sepsis, or posttransplant lymphoproliferative disorder (n = 2). Rejection occurred in 27 patients, including 10 steroid-resistant episodes requiring antilymphoglobulins. The grafts were removed due to uncontrolled rejection in seven ITx recipients. Surgical complications were observed in 38 recipients (25 LSBTx) within 2 months, including bacterial (n = 22) or fungal (n = 11) sepsis, cytomegalovirus disease (n =12), adenovirus (n = 11), or posttransplant lymphoproliferative disorder (n = 12). Forty-two children (19 LSBTx) are alive. Weaning from parenteral nutrition was achieved after 42 days (median). Factors related to death or graft loss were pre-Tx surgery (P < .01), pseudo-obstruction (P < .01), age over 7 years (P < .03), fungal sepsis (P < .03), steroid resistant rejection (P < .05), hospitalized versus home patient (P < .01), and retransplantation (P < .05). Colon transplant did not affect the outcome. Interleukin-2 blockers improved isolated ITx (P < .05). Early referral and close monitoring of intestinal failure and related disorders are mandatory to achieve successful ITx. [Copyright &y& Elsevier]

Prognosis of adult patients with cystic fibrosis (CF), admitted to intensive care unit (ICU), has improved. Few data are available for children. The aim is to describe clinical course and outcomes of CF children hospitalized in ICU. Baseline characteristics of children, reasons for admission in ICU, ventilatory support and outcomes at discharge from ICU were retrospectively analyzed. Non parametric statistical test compared data of survivors at ICU to those with poor outcome (death or lung transplantation in super emergency). From 2000 to 2013, 26 children, median age 13.4 years (1.9–17.6), were admitted to ICU (Necker-Enfants Malades, Paris). Before admission, 15 children (58%) had a non-invasive ventilation (NIV) and 23 (88%) were colonized with Pseudomonas aeruginosa . The median forced expiratory volume (FEV 1 ) was 32% (13–101). Eighteen children (69%) were admitted for respiratory exacerbation, NIV was initiated for 18 (69%) and 9 (35%) were intubated. Half of the 26 children had a poor outcome, 5 (19%) died and 8 (31%) needed urgent lung transplantation. Poor outcome-associated factors were female sex (p = 0.015), history of hemoptysis (p = 0.03), ventilation (p = 0.001) or nutritional (p = 0.017) support before ICU, chronic intravenous antibiotics use (p = 0.001), lower FEV 1 before ICU (27% (13–49) for poor outcome group and 40% (17–101) for survival group, p = 0.036), admission for respiratory exacerbation (p = 0.030), hypercapnia (p = 0.010), metabolic acidosis (p = 0.007) and hypochloremia (p = 0.013). Our study highlights poor outcomes in children hospitalized in ICU and points factors associated with poor outcomes. This will help to improve indications of pediatric lung transplant. [ABSTRACT FROM AUTHOR]