TGFB1, FOXO1, and COMP Genes Expression in Blood of Patients with Osteoarthritis after SARS-CoV2 Infection.

Abstract-Nowadays the possible influence of the coronavirus infection on cartilage degeneration and synovial membrane inflammation during chronic joint pathology-osteoarthritis-remains largely unelucidated. The aim of the presented work is to analyze the TGFB1, FOXO1, and COMP gene expression and free radical generation intensity in blood of patients suffering from osteoarthritis after beating the SARS-CoV2 infection. The work was carried out using molecular genetics and biochemistry methods. The decrease of the TGFB1 and FOXO1 expression level was shown to be more evident in the osteoarthritis patients after COVID-19 if compared to the group with knee osteoarthritis during simultaneous and more prominent diminishing of both superoxide dismutase and catalase activity (possibly indicating cell redox state disruption and TGF- P1-FOXO1 signaling attenuation) in patients with osteoarthritis after SARS-CoV2 disease. At the same time, the more prominent decrease of COMP gene expression level was demonstrated in patients with osteoarthritis after COVID-19 compared to the group with knee osteoarthritis and more intense increase of the COMP concentration in patients with osteoarthritis after the SARS-CoV2 infection was revealed. These data indicate more significant activation of cell destructive processes after the infection as well as further pathology progression.

A general strategy to control antibody specificity against targets showing molecular and biological similarity: Salmonella case study.

The control of antibody specificity plays pivotal roles in key technological fields such as diagnostics and therapeutics. During the development of immunoassays (IAs) for the biosensing of pathogens in food matrices, we have found a way to rationalize and control the specificity of polyclonal antibodies (sera) for a complex analytical target (the Salmonella genus), in terms of number of analytes (Salmonella species) and potential cross-reactivity with similar analytes (other bacteria strains). Indeed, the biosensing of Salmonella required the development of sera and serum mixtures displaying homogeneous specificity for a large set of strains showing broad biochemical variety (54 Salmonella serovars tested in this study), which partially overlaps with the molecular features of other class of bacteria (like specific serogroups of E. coli). To achieve a trade-off between specificity harmonisation and maximization, we have developed a strategy based on the conversion of the specificity profiles of individual sera in to numerical descriptors, which allow predicting the capacity of serum mixtures to detect multiple bacteria strains. This approach does not imply laborious purification steps and results advantageous for process scaling-up, and may help in the customization of the specificity profiles of antibodies needed for diagnostic and therapeutic applications such as multi-analyte detection and recombinant antibody engineering, respectively.

[Nasopharyngeal carriage of SARS-CoV-2 among health personnel with symptoms suggestive of COVID-19 in a University Hospital in the Paris suburbs]. / Évaluation par RT-PCR du portage nasopharyngé du SARS-Cov-2 chez les personnels de santé symptomatiques suspects de COVID-19 dans un CHU de la banlieue parisienne.

INTRODUCTION: A consultation dedicated to symptomatic health professionals was opened at the beginning of the COVID-19 epidemic in order to meet the specific needs of this population. The objective of this work was to estimate the frequency of SARS-Cov-2 nasopharyngeal carriage in symptomatic healthcare workers suspected of having COVID-19 and to determine the factors associated with this carriage. METHODS: Of the 522 consultants, 308 worked in the Hospital and 214 outside. They had mild forms of COVID-19 and non-specific clinical signs with the exception of agueusia/anosmia, which was significantly more common in those with positive RT-PCR. The rate of RT-PCR positivity was 38% overall, without significant difference according to profession. It was higher among external consultants (47% versus 31%). In the hospital, this rate was significantly lower for symptomatic staff in the care sectors, compared to staff in the technical platforms and laboratories (24%, versus 45%, p = 0.006 and 54%, respectively, p < 0.001), but did not differ between staff in COVID units and other care sectors (30% versus 28%). Among the external consultants, the positivity rates of nursing home and private practices staff (53% and 55% respectively) were more than double that of acute care hospital staff (24%, p < 0.001). CONCLUSIONS: These data confirm the strong impact of COVID-19 on health professionals. The higher positivity rates among symptomatic professionals working outside the hospital compared to those working in hospital may be explained in part by a shortage of protective equipment and by difficulties in accessing virological diagnosis, which were greater outside the hospital when the epidemic began.

Sound Coding in the Auditory Nerve: From Single Fiber Activity to Cochlear Mass Potentials in Gerbils.

Auditory nerve fibers (ANFs) convey acoustic information from the sensory cells to the brainstem using an elaborated neural code based on both spike timing and rate. As the stimulus tone frequency increases, time coding fades and ceases, resulting in high-frequency tone encoding that relies mostly on the spike discharge rate. Here, we recapitulated our recent single-unit data from gerbil's auditory nerve to highlight the most relevant mode of coding (spike timing versus spike rate) in tone-in-noise. We report that high-spontaneous rate (SR) fibers driven by low-frequency tones in noise are able to phase lock ∼30 dB below the level that evoked a significant elevation of the discharge rate, whereas medium- and low-SR fibers switch their preferential mode of coding from rate coding in quiet, to time coding in noise. For high-frequency tone, the low-threshold/high-SR fibers reach their maximum discharge rate in noise and do not respond to tones, whereas medium- and low-SR fibers are still able to respond to tones making them more resistant to background noise. Based on these findings, we first discuss the ecological function of the ANF distribution according to their spontaneous discharge rate. Then, we point out the poor synchronization of the low-SR ANFs, accounting for the discrepancy between ANF number and the amplitude of the compound action potential of the of the auditory nerve. Finally, we proposed a new diagnostic tool to assess low-SR fibers, which does not rely on the onset response of the ANFs.

[Orthodontic treatment in children suffering from obstructive sleep apnea]. / Traitement orthodontique chez l'enfant porteur d'un syndrome d'apnées obstructives du sommeil.

The obstructive sleep apnea syndrome (OSAS) may affect children, especially those with dentofacial disharmonies. Dentofacial orthopedic (DFO) treatments carried out in those patients must take this condition into account and can, in selected cases, improve or even treat the OSAS. The goal of our work was to report our experience about DFO treatments of children affected by OSAS in the department of maxillofacial surgery of Femme-Mère-Enfant hospital of university hospitals of Lyon, France.

Computer-assisted intraosseous anaesthesia for molar and incisor hypomineralisation teeth. A preliminary study.

Anesthetizing MIH (Molar and Incisor Hypomineralisation) teeth is one of the major challenges in paediatric dentistry. Computer-assisted IO injection (CAIO) of 4% articaine with 1:200,000 epinephrine (Alphacaine, Septodont) has been shown to be an efficient way to anesthetize teeth in children. The aim of this study was to assess the efficacy of this method with MIH teeth. This preliminary study was performed using the Quick Sleeper system (Dental Hi Tec, Cholet, France) that allows computer-controlled rotation of the needle to penetrate the bone and computer-controlled injection of the anaesthetic solution. Patients (39) of the department of Paediatric Dentistry were included allowing 46 sessions (including 32 mandibular first permanent molars) to be assessed. CAIO showed efficacy in 93.5% (43/46) of cases. Failures (3) were due to impossibility to reach the spongy bone (1) and to achieve anaesthesia (2). This prospective study confirms that CAIO anaesthesia is a promising method to anesthetize teeth with MIH that could therefore be routinely used by trained practitioners.

Production of polyclonal antibodies directed to recombinant methionyl bovine somatotropin.

The administration of recombinant methionyl bovine somatotropin (rMbST) to dairy cows to increase milk yield remains a common practice in many countries including the USA, Brazil, Mexico, South Africa and Korea, whereas it has been forbidden within the European Union (EU) since 1999. A rapid screening immunoanalytical method capable of the unequivocal determination of rMbST in milk would be highly desirable in order to effectively monitor compliance with the EU-wide ban for home-made or imported dairy products. For decades, the production of specific antibodies for this recombinant isoform of bovine somatotropin (bST) has remained elusive, due to the high degree of sequence homology between both counterparts (e.g. methionine for rMbST in substitution of alanine in bST at the N-terminus). In this study, we compared several immunizing strategies for the production of specific polyclonal antibodies (pAbs), based on the use of the full-length recombinant protein, an rMbST N-terminus peptide fragment and a multiple antigen peptide (MAP) which consists of an oligomeric branching lysine core attached to the first two N-terminus amino acids of rMbST, methionine and phenylalanine (MF-MAP). The immunization with KLH-conjugated MF-MAP led to the production of the pAb with the highest rMbST/bST recognition ratio amongst the generated battery of antibodies. The pAb exhibited a specific binding ability to rMbST in a competitive antigen-coated ELISA format, which avidity was further improved after purification by rMbST N-terminus peptide-based affinity chromatography. These results suggest that immunodiscrimination between structurally related proteins can be achieved using immuno-enhanced immunogens such as MAPs.

Molecular variability of group 1 and 5 grass pollen allergens between Pooideae species: implications for immunotherapy.

BACKGROUND: Differences between major allergens from distinct grass species remain to be investigated, both in terms of structure and antigenicity. METHODS: Group 1 and 5 allergens purified from five common Pooideae species were analysed by mass spectrometry (MS). Major histocompatibility complex (MHC) class II-restricted T cell epitopes were identified using predictive algorithms and human leucocyte antigen (HLA)-binding assays. CD4+ T cell reactivity and IgE binding were assessed based on the induction of CD154 expression in peripheral blood mononuclear cells and using competitive ELISA assays, respectively. RESULTS: MS analysis of group 5 pollen allergens reveals considerable intra- and inter-species variability in amino acid sequence, with 30-50 predominant isoforms found for each species. Differences in the amino acid sequence as well as N- and O-glycosylation contribute to the variability of group 1 allergens, yielding 5-10 main isoforms, depending on the species. Out of 14 MHC class II-restricted T cell epitopes identified within group 1, only one is conserved among the five grass species. Significant differences in binding affinities for HLA-DR molecules result in variable CD4+ T cell recognition of group 1 and 5 allergens purified from the various species. Up to 38% and 85% of patients exhibit seric IgE responses to species-restricted (or semi-restricted) epitopes associated with group 1 or 5 allergens, respectively. CONCLUSION: Major pollen allergens from distinct grass species bear both shared and species-restricted T and B cell immune epitopes. When compared with single extracts, a five grass pollen extract is thus more suitable for specific immunotherapy, as it contains a broader repertoire of the IgE epitopes to which patients are sensitized.

Validation of an optical surface plasmon resonance biosensor assay for screening (fluoro)quinolones in egg, fish and poultry.

A surface plasmon resonance biosensor immunoassay has been developed for multi-residue determination of 13 (fluoro)quinolone antibiotics in poultry meat, eggs and fish. The following performance characteristics were determined according to the guidelines laid down for screening assay validation in European Decision 2002/657/EC: detection capability, specificity/selectivity, decision limit, repeatability, ruggedness and stability. The detection capability estimated for norfloxacin, the reference fluoroquinolone, was below 0.5, 1 and 1.5 ng g⁻¹ for poultry meat, egg and fish, respectively. The screening assay proved specific and showed satisfactory sensitivity below the MRL levels even though flumequine and oxolinic acid had lower cross-reactivities. A wide range of non-MRL substances were also detected at concentrations below 10 ng g⁻¹. Repeatability was good with both intra- and inter-assay coefficients of variation 56%; ruggedness was also demonstrated.

Development of an optical surface plasmon resonance biosensor assay for (fluoro)quinolones in egg, fish, and poultry meat.

The aim of this study was to develop an optical biosensor inhibition immunoassay, based on the surface plasmon resonance (SPR) principle, for use as a screening test for 13 (fluoro)quinolones, including flumequine, used as veterinary drugs in food-producing animals. For this, we immobilised various quinolone derivatives on the sensor chip and tested binding of a range of different antibodies (polyclonal and one engineered antibody) in the presence and absence of free (fluoro)quinolones. The main challenge was to detect flumequine in an assay giving good results for the other compounds. One antigen-antibody combination proved satisfactory: polyclonal antibodies raised against a dual immunogen and, on the sensor chip, a fluoroquinolone derivative. It was the first time that this concept of the bi-active antibody was described in the literature. The assay, optimised for detection in three matrices (poultry muscle, fish, and egg), was tested on incurred samples prepared by liquid extraction followed by two washing steps. This rapid, simple method proved adequate for detecting at least 13 (fluoro)quinolones at concentrations below established maximum residue levels (MRLs). The reference molecule norfloxacin could be detected in the range of 0.1-10 microg kg(-1) in extracts of egg and poultry meat and in the range of 0.1-100 microg kg(-1) in extracts of fish. The determined midpoints of these calibration curves were about 1, 1.5 and 3 microg kg(-1) in poultry meat, egg and fish, respectively.

Incidence of residues of nine anticoccidials in eggs.

A survey of the presence of residues of anticoccidials was performed. Three hundred and twenty egg samples, purchased in eight different European countries, were analysed for the presence of nine different compounds: dimetridazole, diclazuril, halofuginone, robenidine, nicarbazin, narasin, salinomycin, lasalocid and monensin. Analyses were performed by LC-MS/MS. Of the samples analysed, 114 (35.6%) contained one or more of the nine anticoccidials in concentrations ranging from 0.1 to 63 microg kg-1. Salinomycin and lasalocid account for more than 60% of all positive samples. Almost 90% of all positive samples contained less than 2 microg kg-1. Results were put into perspective of the farming method and country of origin.

[Development and cardiomyopathy: serum response factor, a key protein]. / Développement et cardiomyopathie: le facteur de réponse au sérum, une protéine clé.

Serum response factor (SRF) is a widely expressed transcription factor involved in the transcription of various genes linked to muscle differentiation and cellular growth. Recent studies show the pivotal role of SRF in orchestrating genetic programs essential for cardiac development and function. Dominant negative isoforms of SRF resulting from caspase cleavage or alternative splicing have been identified in different forms of cardiomyopathies. This review summarizes the role of SRF, its structure, function and its role in human cardiopathies. Finally, we discuss the results of recently developed murine models which address the role of SRF in the adult heart in vivo. The existing biological data suggest that SRF could be a target of neurohumoral activation which is involved in myocardial hypertrophy. Conversely, inhibition of SRF activity in different murine models leads to dilated cardiomyopathy.

Screening for the coccidiostats halofuginone and nicarbazin in egg and chicken muscle: development of an ELISA.

Nicarbazin and halofuginone have been widely used as coccidiostats for the prevention and treatment of coccidiosis in poultry. It has been shown that accidental cross-contamination of feed can lead to residues of these compounds in eggs and/or muscle. This paper describes a direct competitive assay for detecting halofuginone and nicarbazin, developed as qualitative screening assay. In an optimized competitive ELISA, antibodies showed 50% binding inhibition at approximately 0.08 ng ml(-1) for halofuginone and 2.5 ng ml(-1) for dinitrocarbanilide (marker residue for nicarbazin). Extraction from the matrix was carried out with acetonitrile followed by a wash with hexane. The assay's detection capability (CCbeta) for halofuginone was < 0.5 microg kg(-1) in egg and < 1 microg kg(-1) in muscle. For dinitrocarbanilide, the CCbeta was estimated at < 3 microg kg(-1) in egg and < 10 microg kg(-1) in chicken muscle.

Determination of halofuginone in eggs by liquid chromatography/tandem mass spectrometry after cleanup with immunoaffinity chromatography.

A sensitive and very selective high-performance liquid chromatography/tandem mass spectrometric (LC/MS/MS) method for the detection of halofuginone in whole egg has been developed. After deproteinisation with acetonitrile and evaporation of the organic solvent, halofuginone was further isolated by applying immunoaffinity chromatography. The concentrated eluent was injected into the LC/MS/MS system on a C18 column. The precursor ion ([M+H]+) produced by positive electrospray ionisation was selected for fragmentation with argon. Validation parameters such as recovery, linearity and repeatability, decision limit (CCalpha) and detection capability (CCbeta) were determined.

[Biocompatibility and resistance to corrosion of orthodontic wires]. / Résistance à la corrosion et biocompatibilité des fils orthodontiques.

Various materials are currently used to make orthodontic wires. This article suggests a synthesis on their resistance to corrosion and biocompatibility. In the first part, after a review of some basic notions on the corrosion processes, the authors develop the electrochemical characteristics of the three main groups of alloys used in orthodontics. They study more precisely corrosion resistance of nickel-titanium alloys and, through their own experimental results, they show that this type of alloy is subject to corrosion in acid and fluoridated environment. In the second part, the authors study those alloys biocompatibility. They first mention nickel toxicity and allergy induced by this element. Then, biocompatibility of alloys used in orthodontics is assessed following studies on the release of metallic elements from orthodontic wires, and studies on cell-compatibility when in contact with those wires. It is proved that the state of materials surface has a very high influence on their biocompatibility. As a conclusion, in spite of numerous studies carried out so far, showing a satisfactory biological behaviour of those orthodontic wires, many questions are yet to be answered: long term in vivo performances of those materials have not yet been exactly assessed. Further studies must definitely be carried out.

Effects of homocysteine on the cellular responses of murine endothelial cells cultured in vitro.

Homocysteine, derived from the metabolism of methionine, is claimed as a proatherogenic factor that leads to vascular dysfunction. To gain better insight into the molecular mechanisms involved, homocysteine was tested on a model of murine endothelial cells cultured in vitro, using a prototype DNA chip. The DNA chip was designed to follow the expression at the mRNA level of some major proinflammatory genes; TNF-alpha was used as a positive control.

[When to consult an orthodontist?]. / Quand conseiller un orthodontiste?

Orthodontics aims to improve face and teeth harmony and to allow a good development of orofacial and occlusive functions. Orthodontic treatment is adapted to each individual case and may be early or late. Orthodontic indications and management require a collaboration between the paediatrician, the dentist and the orthodontist. The main indications are described.

Key factors determining the course of methyl iodide oxidative addition to diamidonaphthalene-bridged diiridium(I) and dirhodium(I) complexes.

The course of methyl iodide oxidative addition to various nucleophilic complexes, [Ir2(mu-1,8-(NH)2naphth)(CO)2(PiPr3)2] (1), [IrRh(mu-1,8-(NH)2naphth)(CO)2(PiPr3)2] (2), and [Rh2(mu-1,8-(NH)2naphth)(CO)2(PR3)2] (R = iPr, 3; Ph, 4; p-tolyl, 5; Me, 6), has been investigated. The CH3I addition to complex 1 readily affords the diiridium(II) complex [Ir2(mu-1,8-(NH)2naphth)I(CH3)(CO)2(PiPr3)2] (7), which undergoes slow rearrangement to give a thermodynamically stable stereoisomer, 8. The reaction of the Ir-Rh complex 2 gives the ionic compound [IrRh(mu-1,8-(NH)2naphth)(CH3)(CO)2(PiPr3)2]I (10). The dirhodium compounds, 3-5, undergo one-center additions to yield acyl complexes of the formula (Rh2(mu-1,8-(NH)2naphth)I(COCH3)(CO)(PR3)2] (R = iPr, 12; Ph, 13; p-tolyl, 14). The structure of 12 has been determined by X-ray diffraction. Further reactions of these Rh(III)-Rh(I) acyl derivatives with CH3I are productive only for the p-tolylphosphine derivative, which affords the bis-acyl complex [Rh2(mu-1,8-(NH)2naphth)(CH3CO)2I2(P(p-tolyl)3)2] (15). The reaction of the PMe3 derivative, 6, allows the isolation of the bis-methyl complex [Rh2(mu-1,8-(NH)2naphth)(mu-I)(CH3)2(CO)2(PMe3)2]I (16a), which emanates from a double one-center addition. Upon reaction with methyl triflate, the starting materials, 1, 2, 3, and 6, give the isostructural cationic methyl complexes 9, 11, 17, and 18, respectively. The behavior of these cationic methyl compounds toward CH3I, CH3OSO2CF3, and tetrabutylamonium iodide is consistent with the role of these species as intermediates in the SN2 addition of CH3I. Compounds 18 and 17 react with an excess of methyl triflate to give [Rh2(mu-1,8-(NH)2naphth)(mu-OSO2CF3)(CH3)2(CO)2(PMe3)2][CF3SO3] (19) and [Rh2(mu-1,8-(NH)2naphth)(OSO2CF3)(COCH3)(CH3)(CO)(PiPr3)2][CF3SO3] (20), respectively. Upon treatment with acetonitrile, complexes 17 and 18 give the isostructural cationic acyl complexes [Rh2(mu-1,8-(NH)2naphth)(COCH3)(NCCH3)(CO)(PR3)2][CF3SO3] (R = iPr, 21; Me, 22). A kinetic study of the reaction leading to 21 shows that formation of these complexes involves a slow insertion step followed by the fast coordination of the acetonitrile. The variety of reactions found in this system can be rationalized in terms of three alternative reaction pathways, which are determined by the effectiveness of the interactions between the two metal centers of the dinuclear complex and by the steric constraints due to the phosphine ligands.

Correlation of HSP110 expression with all-trans retinoic acid-induced apoptosis.

In a previous study, we observed the strong expression of a stress protein of the HSP100/Clp family (HSP110) in apoptotic mesectodermal cells during early mouse facial development. In the present study, we describe the strong expression of the same HSP110 in mesectodermal cells undergoing apoptosis after all-trans retinoic acid (RA) administration. We used a teratological model known to increase cell deaths mainly in the first and second branchial arches during mammalian cephalogenesis: the treatment of E9 mouse embryos with all-trans RA, which results in craniofacial malformations comparable to those that characterize mandibulofacial dysostosis in man. Pregnant NMRI mice were treated with 60 mg/kg body weight of all-trans RA, given orally on day 9 of gestation; embryos were taken 4, 12 or 24 hr after RA administration. The apoptotic pattern of RA-induced cell deaths was confirmed using the dUTP biotin nick-end labeling (TUNEL) method and transmission electron microscopy (TEM). HSP110 expression was detected using an immunohistochemical approach. The increase in the number of TUNEL-positive cells and HSP110-positive cells after all-trans RA administration was quantified in the first branchial arch using a computerized method. Twelve hours after RA administration, the increase in the number of HSP110-positive cells is greater than the increase in the number of TUNEL-positive cells. Twenty-four hours after RA administration, only TUNEL-positive cells remain strong in number. We suggest that HSP110 expression could represent a biochemical event of apoptotic cell death induced by RA, associated with early stages of the apoptotic process. In order to find out if HSP110 expression resulted from neosynthesis, we performed in situ hybridization, which demonstrated that the expression of HSP110 occurred at the level of mRNA.