[Impact of COVID-19 outbreak on domestic violence and child abuse]. / Face à la COVID-19.Impact de la pandémie COVID-19 sur les maltraitances intrafamiliales dans la population pédiatrique.

Among the somatic and medical consequences of the pandemic linked to COVID-19, the increase in the rate of domestic violence and child abuse is one of the most serious and significant encountered in pediatrics. Indeed, if the reporting rate of ill-treatment of minors was abnormally low during the confinement of March-May 2020, the reopening of schools and psycho-social intervention teams in the spring made it possible to highlight a signifi¬cant increase in the number of worrying clinical situations. In some cases that meet strict hospitalization criteria, the social services call on specialized teams to take care of child victims of abuse. The purpose of this article is to des¬cribe and analyze the child abuse situations handled by the multidisciplinary team Cellule Maltraitance in the Pediatric Department of the CHU Liège between May and November 2020. We will also briefly describe the work and the multi¬disciplinary intervention of the Cellule Maltraitance.

Parmi les conséquences somatiques et médicales de la pandémie liée à la COVID-19, l'augmentation du taux de violences intrafamiliales et de maltraitance infantile est l'une des plus graves et significatives rencon¬trées en pédiatrie. En effet, si le taux de signalement de mauvais traitements envers mineurs fut anormalement bas lors du confinement de mars à mai 2020, la réouverture des milieux scolaires et des équipes d'intervention psy¬cho-sociale au printemps a permis de mettre en lumière une élévation importante du nombre de situations cliniques inquiétantes. Dans certains cas répondant à des critères stricts d'hospitalisation, les services protectionnels tels le Service de l'Aide à la Jeunesse (SAJ) et le Service de Pro¬tection Judiciaire (SPJ) font appel à des équipes hospita¬lières spécialisées afin de prendre en charge les enfants victimes de maltraitance. Cet article a pour objet de décrire et analyser les situations de maltraitance infantile prises en charge par l'équipe pluridisciplinaire Cellule Maltraitance du service de Pédiatrie du Centre Hospitalier Universitaire de Liège entre mai et novembre 2020. Nous décrirons éga¬lement brièvement le travail et l'intervention pluridiscipli¬naire de la Cellule Maltraitance.

[Cat-scratch disease]. / La griffade de chat.

We present three clinical cases to show the diversity of clinical presentations of Bartonella henselae infection, from classical adenopathy to disseminated form. It is an infection that leads to diagnostic wandering, due to a lack of explicit history and the variety of clinical manifestations. Antibiotic therapy is rarely necessary because it has a spontaneously favourable evolution in the majority of cases.

Nous présentons trois cas permettant de montrer l'hétérogénéité des tableaux cliniques de l'infection à Bartonella henselae, de l'adénopathie classique à la forme disséminée. Il s'agit d'une infection qui peut mener à une errance diagnostique, en raison d'une anamnèse parfois peu parlante et de la diversité des présentations cliniques. L'antibiothérapie est rarement nécessaire puisqu'il s'agit d'une maladie à évolution spontanément favorable dans la majorité des cas.

[Kingella kingae bone and joint infections]. / Arthrites à Kingella kingae chez l'enfant : à propos de six cas.

We report six cases of children with probable or confirmed Kingella kingae bone and joint infections (BJI) and discuss the role of this pathogen in the pediatric population. The advent of Polymerase Chain Reaction (PCR) led to the recognition of the importance of Kingella kingae in several human diseases, particularly in BJI affecting children aged 6 to 48 months. Kingella kingae infections in children have most often a good prognosis provided that the diagnosis is discussed, appropriate diagnostic methods are performed and effective antibiotics are prescribed.

Nous rapportons 6 cas probables ou confirmés d'infections ostéoarticulaires (IOA) à Kingella kingae et proposons une revue de l'implication de ce pathogène en pédiatrie. L'avènement de la PCR (Polymerase Chain Reaction) a mis en lumière son rôle dans diverses maladies humaines, en particulier les IOA chez les enfants âgés de 6 à 48 mois. Le pronostic des infections à Kingella kingae chez l'enfant est le plus souvent bon, pour autant que le diagnostic soit évoqué, que les méthodes diagnostiques adéquates soient utilisées et qu'une antibiothérapie appropriée soit instaurée.

[How I treat an acute otitis media in children]. / Comment je traite L'otite moyenne aiguë chez l'enfant.

Acute otitis media (AOM) is very common in early childhood (inferior to 2 years). As a spontaneous recovery occurs in superior to 80 % of cases, antibiotics use should not be systematic. The aim of this review is to discuss AOM diagnostic criteria based on the latest recommendations, aiming a wiser use of antibiotics. Antibiotics use in a child with AOM should take into account the age, the severity of the disease, uni- or bilateral otitis, the presence or absence of otorrhea, and the presence of possible risk factors. Delayed antibiotics prescription might be considered in some specific circumstances. The first line antibiotic treatment is amoxicillin, and increased dosage is efficient in case of resistant pneumococci. Pain evaluation is important, and, in every treatment protocols for AOM, pain-relievers use is needed.

L'otite moyenne aiguë est une affection très fréquente chez les enfants de moins de 2 ans, dont la guérison sera spontanée dans plus de 80 % des cas. Dès lors, une antibiothérapie ne doit pas être systématique. Cette revue reprécise les critères de diagnostic sur base des dernières recommandations publiées pour une utilisation plus judicieuse des antibiotiques. La décision thérapeutique tiendra compte de l'âge de l'enfant, de la sévérité de l'atteinte clinique, du caractère uni- ou bilatéral de l'otite, de la présence d'une otorrhée et d'un éventuel facteur de risque. Une prescription différée d'antibiotiques pourra être discutée dans certaines circonstances. L'amoxicilline reste l'antibiotique de premier choix, en adaptant la posologie pour rester efficace contre les pneumocoques de sensibilité diminuée. L'évaluation de la douleur et le traitement antalgique sont essentiels, quel que soit le choix thérapeutique.

[Two case reports of meningococcemia. Review of the literature on chronic meningococcemia]. / À propos de deux cas de méningococcémie. Revue de la littérature sur la méningococcémie chronique.

INTRODUCTION: Neisseria meningitidis is a Gram-negative bacteria that can be highly pathogenic in humans and responsible for life-threatening and acute diseases. In a few cases, it can lead to an atypical form of sepsis-acute, subacute, or chronic-which, even if progression is slower, may carry the same risks for patients as conventional acute forms. CASES: Case 1 presented with recurrent fever, polyarthralgia, and generalized macular rash. Case 2 had fever for the previous 10days with neck pain and macular rash. Blood cultures were positive for group B meningococcus in both cases. Polymerase chain reaction (PCR) analysis for the same pathogen was also positive in the cerebrospinal fluid (CSF) of Case 2. Following intravenous antibiotic treatment, the progression was favorable in both cases. DISCUSSION: Chronic meningococcemia is characterized by a triad of clinical features, including a fever lasting for at least 1week, arthralgia, and a cutaneous rash. This condition evolves positively without any sequelae if treated properly. PCR and blood culture are two complimentary tools that support the diagnosis. CONCLUSION: Meningococcal infection can manifest in a variety of ways. Chronic meningococcemia diagnosis should be considered in a triad of prolonged fever, rash, and arthralgia. Better access to state-of-the-art techniques such as PCR is recommended in the future so as to provide optimal care of patients suffering from this condition.

Analysis of the Structure and Function of FOX-4 Cephamycinase.

Class C ß-lactamases poorly hydrolyze cephamycins (e.g., cefoxitin, cefotetan, and moxalactam). In the past 2 decades, a new family of plasmid-based AmpC ß-lactamases conferring resistance to cefoxitin, the FOX family, has grown to include nine unique members descended from the Aeromonas caviae chromosomal AmpC. To understand the basis for the unique cephamycinase activity in the FOX family, we determined the first X-ray crystal structures of FOX-4, apo enzyme and the acyl-enzyme with its namesake compound, cefoxitin, using the Y150F deacylation-deficient variant. Notably, recombinant expression of N-terminally tagged FOX-4 also yielded an inactive adenylylated enzyme form not previously observed in ß-lactamases. The posttranslational modification (PTM), which occurs on the active site Ser64, would not seem to provide a selective advantage, yet might present an opportunity for the design of novel antibacterial drugs. Substantial ligand-induced changes in the enzyme are seen in the acyl-enzyme complex, particularly the R2 loop and helix H10 (P289 to N297), with movement of F293 by 10.3 Å. Taken together, this study provides the first picture of this highly proficient class C cephamycinase, uncovers a novel PTM, and suggests a possible cephamycin resistance mechanism involving repositioning of the substrate due to the presence of S153P, N289P, and N346I substitutions in the ligand binding pocket.

[Epidemiology of invasive group A streptococcal infections in developed countries : the Canadian experience with necrotizing fasciitis]. / Épidémiologie des infections invasives à streptocoques du groupe A dans les pays industrialisés : l'exemple des fasciites nécrosantes au Canada.

In industrialized countries, group A streptococcal infections were a source of concern, mainly due to the occurrence of rheumatic fever and its cardiac complications. At present, the incidence of rheumatic fever is decreasing in these countries, giving way to an increasing occurrence of invasive streptococcal group A infections with high level of morbidity and mortality. Streptococcal necrotizing fasciitis, a specific entity, emerged these last decades, often in association with chickenpox. The introduction of the varicella vaccine in the province of Quebec routine immunization program, was followed by a significant decrease in the number of necrotizing fasciitis or other skin and soft-tissues infections in our pediatric population. However, in our experience at the CHU Sainte-Justine, this immunization program has not been helpful to reduce the overall incidence of invasive group A streptococcal infections. Conversely, an increase in the number of pleuro-pulmonary and osteo-articular infections was observed.

Kinematical and EMG-classifications of a fencing attack.

8 expert fencers were studied with a 3-dimensional motion analysis system. Each subject performed 10 flèche attacks toward a standardized target. Surface electromyography signals (EMG) were recorded of the deltoid pars clavicularis, infraspinatus and triceps brachii caput laterale muscles of the weapon arm. The recorded EMGs were averaged using EMG wavelet-transformation software. 4 phases were defined based on the arm kinematics and used to classify fencers into 2 groups. A first group of 4 fencers showed an early maximal elbow extension (Early MEE) whereas the second group presented a late maximal elbow extension (Late MEE). 2 EMG-classifications were based on this kinematical classification, one in the time-domain and the other in the frequency-domain by using the spherical classification. The time-domain EMG-classification showed a significantly ( P=0.03) higher normalized deltoid intensity for the Early MEE group (91 ± 18%) than the Late MEE group (36 ± 13%) in the attack phase. The spherical classification revealed that the activity of all the muscles was significantly classified (recognition rate 75%, P=0.04) between the 2 groups. This study of EMG and kinematics of the weapon upper limb in fencing proposes several classifications, which implies a relationship between kinematic strategies, muscular activations and fencing success.

Development of a pilot-scale 1 for Legionella elimination in biofilm in hot water network: heat shock treatment evaluation.

AIMS: (i) To develop an analytical tool in order to evaluate the effectiveness of anti-Legionella treatment in biofilm and (ii) study the fate of Legionella populations in water and biofilm after applying a heat shock treatment. METHODS AND RESULTS: A pilot-scale unit simulating a hot water system was built and designed by the Scientific and Technical Building Centre (CSTB, France). At the end of the contamination period, a stable cultivable Legionella spp. concentration of 5x10(5) CFU l(-1) was obtained. Two heat shock treatments (70 degrees C for 30 min) were applied. The results showed that the first treatment had a transitional effect on the abatement of Legionella concentrations, while the second treatment had no detectable effect on Legionella populations in water and biofilm. The DAPI (4',6'-diamidino-2-phenylindole), Legionella PCR and GVPC (glycocolle vancomycin pyrophosphate cycloheximide) counts measured in the dead leg water of the Test Loop were 1, 2 and 2 log units higher than results found in the Test Loop water. Moreover, Legionella spp. count in tap water was about 10(4) GU l(-1). These analyses revealed that they are responsible for the rapid recolonization as well as the uncomplete destroyed biofilm. In addition, a resistance test was conducted and showed that Legionella in the second heat shock treatment was not thermo-resistant but thermo-acclimated. CONCLUSION: Thermal disinfection does not seem to be efficient enough to eliminate Legionella when it is used as a curative treatment. SIGNIFICANCE AND IMPACT OF THE STUDY: This work could help water managers for a better management of water network and for a better control of Legionella.

Development of a new method for the detection of lactic acid bacteria capable of protecting ham against Enterobacteriaceae.

AIMS: Challenge trials seem to be the best assessment approach to evaluate the potency of food protective cultures. However, this method is time consuming and often difficult to implement. Here, we describe the development of the 'sequential culturing method', a new method for the screening of strains as protective cultures. METHODS AND RESULTS: The sequential culturing method is based on the simulation, in a meat simulation medium (named BHI5L200), of the inhibition of Enterobacteriaceae by Lactobacillus, observed previously in situ. Results obtained with this sequential culturing method were in good agreement with those of the challenge test on sliced cooked ham and confirmed the antagonistic potency of Lactobacillus. The results obtained from the screening of 187 lactic acid bacteria (LAB) indicated that Lactobacillus sakei, Lactococcus lactis diacetylactis and Carnobacterium spp. were strong inhibitors of Enterobacteriaceae whereas Pediococcus spp., Leuconostoc spp., Weisselia spp. and other species of Lactobacillus and Lactococcus, did not possess the same inhibitory capacity. CONCLUSIONS: Sequential culturing method appeared to be a useful tool to rapidly select LAB cultures which are good candidates for bioprotection of meat. SIGNIFICANCE AND IMPACT OF THE STUDY: Sequential culturing method and simulating media could efficiently mimic challenge test experiments in the selection of potential protective culture for all types of food, on the condition to have the appropriate simulating media, corresponding to the food for which protective cultures were searched.

Rapid and easy development of versatile tools to study protein/ligand interactions.

The system described here allows the expression of protein fragments into a solvent-exposed loop of a carrier protein, the beta-lactamase BlaP. When using Escherichia coli constitutive expression vectors, a positive selection of antibioresistant bacteria expressing functional hybrid beta-lactamases is achieved in the presence of beta-lactams making further screening of correctly folded and secreted hybrid beta-lactamases easier. Protease-specific recognition sites have been engineered on both sides of the beta-lactamase permissive loop in order to cleave off the exogenous protein fragment from the carrier protein by an original two-step procedure. According to our data, this approach constitutes a suitable alternative for production of difficult to express protein domains. This work demonstrates that the use of BlaP as a carrier protein does not alter the biochemical activity and the native disulphide bridge formation of the inserted chitin binding domain of the human macrophage chitotriosidase. We also report that the beta-lactamase activity of the hybrid protein can be used to monitor interactions between the inserted protein fragments and its ligands and to screen neutralizing molecules.

Competitive inhibitors of the CphA metallo-beta-lactamase from Aeromonas hydrophila.

Various inhibitors of metallo-beta-lactamases have been reported; however, none are effective for all subgroups. Those that have been found to inhibit the enzymes of subclass B2 (catalytically active with one zinc) either contain a thiol (and show less inhibition towards this subgroup than towards the dizinc members of B1 and B3) or are inactivators behaving as substrates for the dizinc family members. The present work reveals that certain pyridine carboxylates are competitive inhibitors of CphA, a subclass B2 enzyme. X-ray crystallographic analyses demonstrate that pyridine-2,4-dicarboxylic acid chelates the zinc ion in a bidentate manner within the active site. Salts of these compounds are already available and undergoing biomedical testing for various nonrelated purposes. Pyridine carboxylates appear to be useful templates for the development of more-complex, selective, nontoxic inhibitors of subclass B2 metallo-beta-lactamases.

Lactococcin MMT24, a novel two-peptide bacteriocin produced by Lactococcus lactis isolated from rigouta cheese.

Lactococcin MMT24 is a novel bacteriocin produced by Lactococcus lactis MMT24, a strain isolated from a Tunisian traditional cheese. The bacteriocin shows a narrow antimicrobial activity against closely related lactic acid bacteria. Lactococcin MMT24 is heat resistant, remains active after incubation at pH 3 to 10, lyophilization, long-term storage at -20 degrees C and is sensitive to treatment with proteolytic enzymes. The mode of action of lactococcin MMT24 was identified as bactericidal. Purification of the active compound showed that lactococcin MMT24 consists of two distinct peptides, named pepalpha and pepbeta, whose complementary action is necessary for full antibacterial activity. Optimal antibacterial activity was obtained when the complementary peptides pepalpha and pepbetawere present in equal amounts. Mass spectrometry analysis showed masses of 3765.33 Da and 3255.26 Da for pepalpha and pepbeta, respectively. These molecular masses do not correspond to those of so far described bacteriocins. Addition of 50 nmol l(-1) of lactococcin MMT24 to cells of L. lactis ssp. cremoris ATCC11603 induced increase in the concentration of K+ in supernatant indicating a massive leakage of this ion from the cells. This release was most likely caused by pores formation by the pepalphaand pepbeta peptides in the target bacterial membrane.

Inhibition of class D beta-lactamases by acyl phosphates and phosphonates.

The susceptibility of typical class D beta-lactamases to inhibition by acyl phosph(on)ates has been determined. To a large degree, these class D enzymes behaved very similarly to the class A TEM beta-lactamase towards these reagents. Dibenzoyl phosphate stood out in both cases as a lead compound towards a new class of effective inhibitors.

Molecular characterisation of a versatile peroxidase from a Bjerkandera strain.

The cloning and sequencing of the rbpa gene coding for a versatile peroxidase from a novel Bjerkandera strain is hereby reported. The 1777 bp isolated fragment contained a 1698 bp peroxidase-encoding gene, interrupted by 11 introns. The 367 amino acid-deduced sequence includes a 27 amino acid-signal peptide. The molecular model, built via homology modelling with crystal structures of four fungal peroxidases, highlighted the amino acid residues putatively involved in manganese binding and aromatic substrate oxidation. The potential heme pocket residues (R44, F47, H48, E79, N85, H177, F194 and D239) include both distal and proximal histidines (H48 and H177). RBP possesses potential calcium-binding residues (D49, G67, D69, S71, S178, D195, T197, I200 and D202) and eight cysteine residues (C3, C15, C16, C35, C121, C250, C286, C316). In addition, RBP includes residues involved in substrate oxidation: three acidic residues (E37, E41 and D183)--putatively involved in manganese binding and H83 and W172--potentially involved in oxidation of aromatic substrates. Characterisation of nucleotide and amino acid sequences include RBP in versatile peroxidase group sharing catalytic properties of both LiP and MnP. In addition, the RBP enzyme appears to be closely related with the ligninolytic peroxidases from the Trametes versicolor strain.

Electronic and molecular properties of an adsorbed protein monolayer probed by two-color sum-frequency generation spectroscopy.

Two-color sum-frequency generation spectroscopy (2C-SFG) is used to probe the molecular and electronic properties of an adsorbed layer of the green fluorescent protein mutant 2 (GFPmut2) on a platinum (111) substrate. First, the spectroscopic measurements, performed under different polarization combinations, and atomic force microscopy (AFM) show that the GFPmut2 proteins form a fairly ordered monolayer on the platinum surface. Next, the nonlinear spectroscopic data provide evidence of particular coupling phenomena between the GFPmut2 vibrational and electronic properties. This is revealed by the occurrence of two doubly resonant sum-frequency generation processes for molecules having both their Raman and infrared transition moments in a direction perpendicular to the sample plane. Finally, our 2C-SFG analysis reveals two electronic transitions corresponding to the absorption and fluorescence energy levels which are related to two different GFPmut2 conformations: the B (anionic) and I forms, respectively. Their observation and wavelength positions attest the keeping of the GFPmut2 electronic properties upon adsorption on the metallic surface.