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Measurement of quantitative antibody responses are increasingly important in evaluating the immune response to infection and vaccination. In this study we describe the validation of a quantitative, multiplex serologic assay utilising an electrochemiluminescence platform, which measures IgG against the receptor binding domain (RBD), spike S1 and S2 subunits and nucleocapsid antigens of SARS-CoV-2. The assay displayed a sensitivity ranging from 73 to 91% and specificity from 90 to 96% in detecting previous infection with SARS-CoV-2 depending on antigenic target and time since infection, and this assay highly correlated with commercially available assays. The within-plate coefficient of variation ranged from 3.8-3.9% and the inter-plate coefficient of variation from 11 to 13% for each antigen., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

We reported recently that the Parkinsonism-associated protein DJ-1 and its bacterial homologs Hsp31, YhbO and YajL function as deglycases that repair proteins and nucleotides from endogeneous glycation by glyoxal and methylglyoxal, two reactive by-products of glucose metabolism responsible for up to 60% of glycation damage. Here, we show that DJ-1, deglycase 1 and deglycase 2 repair glyoxal- and methylglyoxal-glycated substrates, whereas deglycase 3 principally repairs glyoxal-glycated substrates. Moreover, deglycase 1 and 2 are overexpressed in stationary phase, whereas deglycase 3 is steadily expressed throughout bacterial growth. Finally, deglycase mutants overexpress glyoxalases, aldoketoreductases, glutathione-S-transferase and efflux pumps to alleviate carbonyl stress. In the discussion, we present an overview of the multiple functions of DJ-1 proteins. Our thourough work on deglycases provides compelling evidence that their previously reported glyoxalase III activity merely reflects their deglycase activity. Moreover, for their deglycase activity the Maillard deglycases likely recruit: i) their chaperone activity to interact with glycated proteins, ii) glyoxalase 1 activity to catalyze the rearrangement of Maillard products (aminocarbinols and hemithioacetals) into amides and thioesters, respectively, iii) their protease activity to cleave amide bonds of glycated arginine, lysine and guanine, and iv) glyoxalase 2 activity to cleave thioester bonds of glycated cysteine. Finally, because glycation affects many cellular processes, the discovery of the Maillard deglycases, awaited since 1912, likely constitutes a major advance for medical research, including ageing, cancer, atherosclerosis, neurodegenerative, post-diabetic, renal and autoimmune diseases., (Copyright © 2018. Published by Elsevier Inc.)

The human DEAD-box helicase DDX3 is a multi-functional protein involved in the regulation of gene expression and additional non-conventional roles as signalling adaptor molecule that are independent of its enzymatic RNA remodeling activity. It is a nucleo-cytoplasmic shuttling protein and it has previously been suggested that dysregulation of its subcellular localization could contribute to tumourigenesis. Indeed, both tumour suppressor and oncogenic functions have been attributed to DDX3. In this study, we investigated the regulation of DDX3's nucleocytoplasmic shuttling. We confirmed that an N-terminal conserved Nuclear Export Signal (NES) is required for export of human DDX3 from the nucleus, and identified three regions within DDX3 that can independently facilitate its nuclear import. We also aimed to identify conditions that alter DDX3's subcellular localisation. Viral infection, cytokine treatment and DNA damage only induced minor changes in DDX3's subcellular distribution as determined by High Content Analysis. However, DDX3's nuclear localization increased in early mitotic cells (during prophase) concomitant with an increase in DDX3 expression levels. Our results are likely to have implications for the proposed use of (nuclear) DDX3 as a prognostic biomarker in cancer., (Copyright © 2018 Elsevier GmbH. All rights reserved.)

Objectives: This study was conducted to determine hemodynamic and clinical tolerance under short-stretch compression therapy in elderly patients suffering from mixed-etiology leg ulcers., Design: Transversal observational study conducted in 25 hospitalized patients with a moderate peripheral arterial occlusive disease defined as an ankle-brachial pressure index>0.5, an ankle pressure of>70mmHg and a toe cuff pressure (TP)>50mmHg., Material and Methods: Short-stretch bandages were applied daily with pressures from 20 to 30mmHg. Ankle-brachial pressure, great toe laser Doppler flowmetry (LDF) and transcutaneous oxygen pressure (TcPO2) on dorsum of the foot were measured at baseline and after its removal at 24hours. Great toe LDF was also measured at 10minutes after bandage application. Compression pressure (CP) was measured with a sub-bandage device at baseline, at 10minutes and before bandage removal at 24hours. Clinical tolerance was evaluated taking into account the patient's pain and skin tolerance., Results: Mean age of patients was 80±15 years. Median duration of ulcers was 18 months. Hypertension was highly prevalent. One third of patients had diabetes. Toe pressure index and TcPO2 values did not significantly change under compression therapy (P=0.51 and P=0.09, respectively) whereas CP decreased significantly during 24hours. The loss of CP was significant 10minutes after bandage application (P<0.001). Nearly all ulcers were painful prior to placement of compression therapy and required level 1 analgesics. One patient required level 2 analgesic for pain relief. No increase in pain and no ischemic skin damage occurred under compression therapy., Conclusions: In elderly patients with mixed leg ulcers and with an absolute TP>50mmHg, short-stretch compression of up to 30mmHg does not adversely affect arterial flow and appears clinically well tolerated. Such bandages with appropriate levels of compression may aid ulcer healing by treating the venous part of the disease., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Objective: A vascular cause is found in around 85% of leg ulcer patients, but non-vascular causes are also observed. Their diagnosis is based on a set of clinical arguments and skin biopsy with histological analysis. The aim of this study was to analyze the results of these biopsies and to find common criteria for ulcers whose skin biopsies had led to the diagnosis of a non-vascular ulcer., Material and Method: A retrospective study was carried out on the analysis of 143 skin biopsies of leg ulcers. The reasons for the biopsy were mainly atypical clinical signs and/or the lack of improvement in care after 6 months, as advocated by the French health authorities., Results: The skin biopsies led to a diagnosis of non-vascular ulcer in 4.9% of cases (7/143), including skin cancer (n=5, 3.5%), cutaneous leishmaniasis (n=1, 0.7%) and Pyoderma gangrenosum (n=1, 0.7%). The univariate statistical analysis revealed that an elevated rim and abnormal excessive granulation tissue were significantly more frequently found in these ulcers. All patients with a positive skin biopsy had associated vascular involvement., Conclusion: This study found a 5% rate of non-vascular causes of ulcers, mainly skin cancer. Elevated rims and abnormal excessive granulation tissue were the unusual features most commonly found in these ulcers. All patients whose skin biopsy revealed a non-vascular cause had associated vascular involvement. This information confirms the need to perform a skin biopsy, even in the presence of a vascular disease., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Objective: Isochromosome of the long arm of chromosome 20 (i(20q)) is a rare structural abnormality in prenatal diagnosis. Thirty prenatal cases of mosaic i(20q) have been reported, among which only four are associated with fetal malformations. We describe a new prenatal case of i(20q) with fetal malformations., Materials and Methods: We also observed a discrepancy between uncultured and cultured amniotic fluid cells by using conventional cytogenetic, fluorescence in situ hybridization and array-SNP analysis., Results: The short arm deletion of chromosome 20 arising from the isochromosome encompassed two candidate genes PAX1 and JAG1 involved in cranio-facial and vertebral development., Conclusion: The data would allow establishing a phenotype-genotype correlation. Thus, we proposed to define a recognizable syndrome combining cranio-facial dysmorphism, vertebral bodies' anomalies, feet and cerebral malformations., (Copyright © 2017. Published by Elsevier B.V.)

Filamentous ascomycetes produce complex multicellular structures during sexual reproduction. Little is known about the genetic pathways enabling the construction of such structures. Here, with a combination of classical and reverse genetic methods, as well as genetic mosaic and graft analyses, we identify and provide evidence for key roles for two genes during the formation of perithecia, the sexual fruiting bodies, of the filamentous fungus Podospora anserina. Data indicate that the proteins coded by these two genes function cell-non-autonomously and that their activity depends upon conserved cysteines, making them good candidate for being involved in the transmission of a reactive oxygen species (ROS) signal generated by the PaNox1 NADPH oxidase inside the maturing fruiting body towards the PaMpk1 MAP kinase, which is located inside the underlying mycelium, in which nutrients are stored. These data provide important new insights to our understanding of how fungi build multicellular structures., (Copyright © 2016 Elsevier Inc. All rights reserved.)

YhbO and YajL belong to the PfpI/Hsp31/DJ-1 superfamily. Both proteins are involved in protection against environmental stresses. Here, we show that, like DJ-1 and Hsp31, they repair glyoxal- and methylglyoxal-glycated proteins. YhbO and YajL repair glycated serum albumin, collagen, glyceraldehyde-3-phosphate dehydrogenase, and fructose biphosphate aldolase. Bacterial extracts from deglycase mutants display increased glycation levels, whereas deglycase overexpression decreases protein glycation. Moreover, yhbO and yajL mutants display decreased viability in methylglyoxal- or glucose-containing media. Finally, the apparent glyoxalase activities of YhbO and YajL reflect their deglycase activities., (Copyright © 2016 Elsevier Inc. All rights reserved.)

YajL is the closest Escherichia coli homolog of the Parkinsonism-associated protein DJ-1, a multifunctional oxidative stress response protein whose biochemical function remains unclear. We recently described the oxidative-stress-dependent aggregation of proteins in yajL mutants and the oxidative-stress-dependent formation of mixed disulfides between YajL and members of the thiol proteome. We report here that yajL mutants display increased protein sulfenic acids levels and that formation of mixed disulfides between YajL and its protein substrates in vivo is inhibited by the sulfenic acid reactant dimedone, suggesting that YajL preferentially forms disulfides with sulfenylated proteins. YajL (but not YajL(C106A)) also forms mixed disulfides in vitro with the sulfenylated form of bovine serum albumin. The YajL-serum albumin disulfides can be subsequently reduced by glutathione or dihydrolipoic acid. We also show that DJ-1 can form mixed disulfides with sulfenylated E. coli proteins and with sulfenylated serum albumin. These results suggest that YajL and possibly DJ-1 function as covalent chaperones involved in the detection of sulfenylated proteins by forming mixed disulfides with them and that these disulfides are subsequently reduced by low-molecular-weight thiols., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Escherichia coli contains two thioredoxins, Trx1 and Trx2, and a thioredoxin-like protein, YbbN, that displays both redox and chaperone properties. Since three out of the six proteins of the YbbN interactome (Butland et al., 2005) are components of DNA polymerase 3 holoenzyme (i.e. the β-clamp DnaN, the θ subunit HolE and the δ' subunit HolB), we investigated whether the ybbN mutant presents DNA replication defects. We found that this mutant incorporates (3)H-thymidine at higher rates than the parental strain and displays overinitiation, hypermutator and filamentation phenotypes with the occurrence of anucleated cells. Moreover, YbbN functions as a bona fide chaperone in the refolding of the urea-unfolded β-clamp. These results suggest that the DNA replication and cell division defects of the ybbN mutant might best be explained by chaperone functions of YbbN in the biogenesis of DNA polymerase 3 holoenzyme., (Copyright © 2010 Elsevier Inc. All rights reserved.)

From 2002 to 2006, 35 of 73 multidrug-resistant Pseudomonas aeruginosa isolates from different wards at Charles Nicolle hospital of Tunis were positive for class B carbapenemase (using the imipenem-EDTA test), owing to a bla(VIM-2) gene cassette in a class 1 integron. Twenty-three isolates additionally produced the extended-spectrum beta-lactamase SHV2a. DNA sequences immediately surrounding bla(SHV2a) shared extensive identity with a Klebsiella pneumoniae plasmid sequence. Despite belonging to the same chromosomal type, as shown by pulsed-field gel electrophoresis (PFGE), the VIM-2 producing P. aeruginosa isolates prevalent at Charles Nicolle hospital displayed a diversity of VIM-2-carrying integrons.

Aim of the Study: To determine the prevalence and the diversity of extended-spectrum beta-lactamases (ESBLs) in 196 Klebsiella pneumoniae clinical isolates collected from three hospitals in Algiers., Materials and Methods: Antibiograms were done on Mueller-Hinton agar plates with the disc-diffusion method and MICs were determined by agar-dilution method. Mating experiments were performed in agar medium. Plasmid DNA was extracted by the alcalin-lysis method. Total DNA was extracted with a Qiagen mini kit and screened for bla(TEM) and bla(CTX-M) genes by PCR. Linkage of bla(CTX-M) genes with insertion sequence ISEcp1B and class 1 integrons was investigated by PCR. PCR products were sequenced by the Sanger method. The epidemiological relationships between ESBL-producing K. pneumoniae isolates were analyzed by ERIC-PCR., Results: Thirty-nine (19.9%) isolates were found to produce ESBLs belonging to CTX-M-1 group and TEM penicillinases (CTX-M-3, CTX-M-15 and TEM-1). ERIC-PCR analysis showed that the isolates are genetically unrelated. The bla(TEM) and bla(CTX-M) genes as well as aminoglycosides and sulfonamides resistance determinants were found located in self-transferable plasmids of approximately 85 kb. The class 1 integrons and the insertion sequence ISEcp1B were present in the isolates and in their transconjugants. ISEcp1B was found genetically linked to the bla(CTX-M) genes and located 127bp upstream, with the presence of the V and W sequences., Conclusion: The study revealed a high rate of ESBL-producing K. pneumoniae in Algerian hospitals, resulting from horizontal dissemination of mobile bla(CTX-M) genes.

This report describes the first occurrence of the DHA-1 ampCbeta-lactamase gene in Proteus mirabilis. The organism was isolated from the vaginal flora of a pregnant woman in a French hospital. The DHA-1 beta-lactamase gene was identified on the basis of phenotypic characteristics, PCR amplification and sequencing. Antagonism between cefoxitin and the other cephalosporins suggested inducible production of the DHA-1 enzyme.

Inspiratory muscle function has been shown to be related to general muscle weakness, weight loss, blood gas tensions, airway obstruction and hyperinflation. The aim of this study was to define (1) the factor that is the main determinant of the tension-time index of the inspiratory muscles (TTmus), and which this increases the risk of inspiratory muscle fatigue; and (2) whether a breathing strategy is adopted to avoid inspiratory muscle fatigue. Twenty-seven normal volunteers and 35 stable COPD outpatients (FEV1% predicted, range: 21-89%; and FRC/TLC, range: 49-77%) were studied. The TTmus was determined as follows: TTmus = PI/PImax.TI/Ttot, where Pi is the mean inspiratory pressure calculated from the mouth occlusion pressure (P0.1), PImax is the maximal inspiratory pressure, TI is the inspiratory time, and Ttot is the total time of the breathing cycle. COPD patients showed significantly lower PImax and higher P0.1, PI, PI/PImax, and TTmus than normal subjects. No patient had a TTmus value higher than the inspiratory muscle fatigue threshold of 0.33. The FEV1 was significantly correlated with TTmus and all its components in the patients. The FRC/TLC was also correlated with all components except PI. Body weight was only correlated with PImax. In a forward and backward stepwise regression analysis, FEV1 appeared to be the only significant factor explaining the variance of log (PI/PImax) and log (TTmus), whereas FRC/TLC was the principal determinant of PImax. In COPD patients, a non-linear relationship was found between TI and P0.1. A negative linear relationship was found between TI/Ttot and PI/PImax. In conclusion, although hyperinflation predominantly affected inspiratory muscle strength in a group of stable COPD patients with a wide range of severity, airway obstruction was the principal factor determining the magnitude of TTmus. In addition, in order to remain below the inspiratory muscle fatigue threshold, as the severity of airway obstruction increased, patients adopted a breathing strategy characterized by decreased TI/Ttot as inspiratory pressure demand increased.

Study Objective: The aims of this work were to determine (1) whether patients with COPD have impaired skeletal muscle performance (ie, maximal strength and endurance) compared with healthy subjects, and (2) whether the level of physical activity, body composition, and lung function are related to skeletal muscle performance in COPD patients., Methods: Seventeen COPD patients and eight healthy age-matched control subjects performed maximum voluntary contraction (MVC) of the quadriceps and an endurance test consisting of dynamic contractions of the quadriceps against 20% of MVC at an imposed regular pace until exhaustion. The endurance test duration determined the muscle "limit time" (Tlim). A score of physical activity (PA score) was obtained using an adapted physical activity questionnaire for the elderly, and body composition was measured by the bioelectrical impedance method. Symptom-limited oxygen uptake (VO2 sl) was also assessed in COPD patients using a maximal incremental exercise test., Results: The results showed that Tlim and PA score were significantly decreased in COPD patients (p<0.05). Significant positive correlations were found in the COPD group between Tlim and the PA score (r=0.60; p<0.05), FEV1 (r=0.52; p<0.05), and PaO2 (r=0.63; p<0.05). The same results were found between the PA score and VO2 sl (r=0.57; p<0.05) and FEV1 (r=0.63; p<0.05)., Conclusion: These findings indicate impaired skeletal muscle endurance in COPD patients related to altered lung function and associated physical inactivity.

The measurement of the activity of cholesteryl ester transfer protein (CETP), is of high clinical interest and this study reports the use of a direct LDL isolation (d-LDL) technique to determine in one step the amount of radiolabeled cholesteryls esters ([3H]-CE) transferred from exogenous HDL3 to LDL, avoiding the conveniences of the usually used ultracentrifugation or precipitation of apo-B containing lipoproteins in the CETP methodologies. The d-LDL technique providing a specific immunoprecipitation of VLDL, IDL and HDL allowed to directly determine the [3H]-CE transferred on LDL (d-[3H]-CE-LDL). Two methodologies were assayed for the CETP activity using either exogenous or endogenous lipoproteins, and the results with the d-LDL technique were compared with those obtained using the ultracentrifugation (u-[3H]-CE-LDL) considered as the reference method. The intra- and inter-assays were similar in both techniques for the two CETP activity assays. Strong positive correlations were established between values obtained with d-[3H]-CE-LDL and u-[3H]-CE-LDL isolation procedures for CETP activities with exogenous or endogenous lipoproteins (r = 0.972; p = 0.0001 and r = 0.965; p = 0.0001 respectively). In conclusion, the d-LDL technique represents an easy and accurate procedure to measure directly, in normotriglyceridemic plasmas, the amount of [3H]-CE transferred from HDL to LDL by the CETP.

Chemotherapy of lung cancer is still an experimental approach requiring careful evaluation. Tumour response (marker of anticancer activity) is not perfectly correlated to survival (marker of chemotherapy efficacy), but its evaluation remains a milestone inasmuch as reporting a wrong tumour response rate might lead to the rejection of active new treatments. This review deals with the method of tumour response measurements and its use during a chemotherapy protocol. Recommendations drawn from the analysis of the literature are: 1) to assess and classify all lesions which can be identified at the beginning of the treatment; 2) to define the target lesions, mainly the ones which can be bidimensionally measured; 3) to use the World Health Organization recommendations for reporting the overall response; 4) to confirm complete response by negative rebiopsies; 5) to avoid second fiberoptic bronchoscopy to patients with stable or progressive disease on CT-scan, and finally; 6) to assess response quality by evaluating response duration and improvement of quality of life.

Tumor response is one of the most important criteria in the analysis of chemotherapy. A chest computed tomographic (CT) scan and fiberoptic bronchoscopy (FOB) might give different results, as they analyze different aspects of the effects of chemotherapy on lung cancer. The response of the chest tumor in 103 patients with stage III or IV lung cancer (35 with small-cell lung cancer [SCLC] and 68 with non-small-cell lung cancer [NSCLC]) who prospectively entered chemotherapy trials was studied in order to determine the concordance between the chest CT scan and FOB. The chest CT scan allowed an assessment of tumor response in almost all patients, whereas FOB was not able to evaluate this response in 15 of the 103. The frequency of an evaluable endobronchial lesion did not depend on histology (SCLC, 97 percent; NSCLC, 93 percent; chi 2 = 0.85; not significant [NS]) or tumor T classification (T1-2, 83 percent; T3, 94 percent; T4, 97 percent; chi 2 = 1.49; NS). Tumor location in the bronchial airway did not differ when SCLC and NSCLC were compared. Thus, it is not possible to predict a subgroup of patients in whom FOB may be optional. In the group of 88 patients who were evaluable for response using both FOB and CT scan, a statistical concordance of the response classification was observed. The response was overevaluated by CT scan in 22 patients for whom data obtained by FOB appeared to be critical in the evaluation of tumor response. The concordance of response data obtained when the 2 methods were used was lower in NSCLC in comparison with SCLC. Thus, the use of FOB in the analysis of tumor response might be important, especially for NSCLC, inasmuch as FOB modulates the CT-evaluated response.