Posttranscriptional Regulation of the Human LDL Receptor by the U2-Spliceosome.

BACKGROUND: The LDLR (low-density lipoprotein receptor) in the liver is the major determinant of LDL-cholesterol levels in human plasma. The discovery of genes that regulate the activity of LDLR helps to identify pathomechanisms of hypercholesterolemia and novel therapeutic targets against atherosclerotic cardiovascular disease. METHODS: We performed a genome-wide RNA interference screen for genes limiting the uptake of fluorescent LDL into Huh-7 hepatocarcinoma cells. Top hit genes were validated by in vitro experiments as well as analyses of data sets on gene expression and variants in human populations. RESULTS: The knockdown of 54 genes significantly inhibited LDL uptake. Fifteen of them encode for components or interactors of the U2-spliceosome. Knocking down any one of 11 out of 15 genes resulted in the selective retention of intron 3 of LDLR. The translated LDLR fragment lacks 88% of the full length LDLR and is detectable neither in nontransfected cells nor in human plasma. The hepatic expression of the intron 3 retention transcript is increased in nonalcoholic fatty liver disease as well as after bariatric surgery. Its expression in blood cells correlates with LDL-cholesterol and age. Single nucleotide polymorphisms and 3 rare variants of one spliceosome gene, RBM25, are associated with LDL-cholesterol in the population and familial hypercholesterolemia, respectively. Compared with overexpression of wild-type RBM25, overexpression of the 3 rare RBM25 mutants in Huh-7 cells led to lower LDL uptake. CONCLUSIONS: We identified a novel mechanism of posttranscriptional regulation of LDLR activity in humans and associations of genetic variants of RBM25 with LDL-cholesterol levels.

Association Between Increased Linezolid Plasma Concentrations and the Development of Severe Toxicity in Multidrug-Resistant Tuberculosis Treatment.

BACKGROUND: Treatment of multidrug-resistant (MDR) tuberculosis with linezolid is characterized by high rates of adverse events. Evidence on therapeutic drug monitoring to predict drug toxicity is scarce. This study aimed to evaluate the association of linezolid trough concentrations with severe toxicity. METHODS: We retrospectively assessed consecutive patients started on linezolid for MDR tuberculosis between 2011 and 2017. The primary outcome was severe mitochondrial toxicity (SMT) due to linezolid, defined as neurotoxicity or myelotoxicity leading to drug discontinuation. The impact of plasma linezolid trough concentrations >2 mg/L was assessed in multivariate Cox proportional hazards models including time-varying covariates. RESULTS: SMT occurred in 57 of 146 included patients (39%) at an incidence rate of 0.38 per person-year (95% confidence interval, .30-.49). A maximum linezolid trough concentration >2 mg/L was detected in 52 patients (35.6%), while the mean trough concentration was >2 mg/L in 22 (15%). The adjusted hazard ratio for SMT was 2.35 (95% confidence interval, 1.26-4.38; P = .01) in patients with a mean trough concentration >2 mg/L and 2.63 (1.55-4.47; P < .01) for SMT after the first detection of a trough concentration >2 mg/L. In an exploratory analysis, higher maximum trough concentrations were dose-dependently associated with toxicity, while lowering elevated trough concentrations did not restore baseline risk. CONCLUSIONS: Linezolid trough concentrations >2 mg/L are strongly associated with the development of severe treatment-emergent toxicity in patients treated for MDR tuberculosis. Pending further prospective evidence, an individual risk-benefit assessment on the continuation of linezolid treatment is warranted in any patient with trough concentrations >2 mg/L.

Active tuberculosis screening among the displaced population fleeing Ukraine, France, February to October 2022.

Persons fleeing Ukraine since February 2022 have potentially higher risk of tuberculosis (TB) vs all European Union countries. Interest of active TB screening among this population is debated and not widely adopted. In this screening intervention by a network of TB centres in France, the number needed to screen (NNS) was 862 to find one case. This experience shows that this strategy may be relevant for TB control in situations of massive displacement, similar to that following the Russian invasion.

Revised Definitions of Tuberculosis Resistance and Treatment Outcomes, France, 2006-2019.

Definitions of resistance in multidrug-resistant tuberculosis (MDR TB) and extensively drug-resistant tuberculosis (XDR TB) have been updated. Pre-XDR TB, defined as MDR TB with additional resistance to fluoroquinolones, and XDR TB, with additional resistance to bedaquiline or linezolid, are frequently associated with treatment failure and toxicity. We retrospectively determined the effects of pre-XDR/XDR TB resistance on outcomes and safety of MDR TB treatment in France. The study included 298 patients treated for MDR TB at 3 reference centers during 2006-2019. Of those, 205 (68.8%) cases were fluoroquinolone-susceptible MDR TB and 93 (31.2%) were pre-XDR/XDR TB. Compared with fluoroquinolone-susceptible MDR TB, pre-XDR/XDR TB was associated with more cavitary lung lesions and bilateral disease and required longer treatment. Overall, 202 patients (67.8%) had favorable treatment outcomes, with no significant difference between pre-XDR/XDR TB (67.7%) and fluoroquinolone-susceptible MDR TB (67.8%; p = 0.99). Pre-XDR/XDR TB was not associated with higher risk for serious adverse events.

atpE Mutation in Mycobacterium tuberculosis Not Always Predictive of Bedaquiline Treatment Failure.

We report the emergence of an atpE mutation in a clinical Mycobacterium tuberculosis strain. Genotypic and phenotypic bedaquiline susceptibility testing displayed variable results over time and ultimately were not predictive of treatment outcome. This observation highlights the limits of current genotypic and phenotypic methods for detection of bedaquiline resistance.

Association of Healthcare and Aesthetic Procedures with Infections Caused by Nontuberculous Mycobacteria, France, 2012‒2020.

We describe nontuberculous mycobacteria (NTM) infections during 2012-2020 associated with health care and aesthetic procedures in France. We obtained epidemiologic data from the national early warning response system for healtcare-associated infections and data on NTM isolates from the National Reference Center for Mycobacteria. We compared clinical and environmental isolates by using whole-genome sequencing. The 85 original cases were reported after surgery (48, 56%), other invasive procedures (28, 33%) and other procedures (9, 11%). NTM isolates belonged to rapidly growing (73, 86%) and slowly growing (10, 12%) species; in 2 cases, the species was not identified. We performed environmental investigations for 38 (45%) cases; results for 12 (32%) were positive for the same NTM species as for the infection. In 10 cases that had environmental and clinical samples whose genomes were similar, the infection source was probably the water used in the procedures. NTM infections could be preventable by using sterile water in all invasive procedures.

A Magnetocaloric Glass from an Ionic-Liquid Gadolinium Complex.

[Gd5 (L)16 (H2 O)8 ](Tf2 N)15 was obtained from reaction of Gd2 O3 with 1-carboxymethyl-3-ethylimidazolium chloride (LHCl). The material was found to be an ionic liquid that freezes to glassy state on cooling to -30 °C. Variable-temperature magnetic studies reveal the presence of weak magnetic intramolecular interactions in the glass. Isothermal variable-field magnetization demonstrates a magnetocaloric effect (MCE), which is the first finding of such an effect in a molecular glass. This MCE is explainable by an uncoupled representation, with a magnetic entropy change of -11.36 J K-1 kg-1 at 1.8 K for a 0-7 T magnetic field change, and with a refrigerant capacity of 125.9 J kg-1 , in the 1.8-50 K interval.

Do Contact Precautions Reduce the Incidence of Intensive Care Unit-Acquired Pseudomonas aeruginosa Infections? The DPCPYO (Detection and Contact Precautions for Patients With P. aeruginosa) Cluster-Randomized Crossover Trial.

BACKGROUND: The issue of contact precautions as contributory factors for reducing Pseudomonas aeruginosa (Pa) infections in intensive care units (ICUs) remains questioned. We evaluated the impact of the addition of contact precautions to standard precautions for Pa-positive patients on incidence of ICU-acquired Pa infections. METHODS: In this multicenter, cluster-randomized crossover trial, 10 French ICUs were randomly assigned (1:1) to sequence 0-1 (6-month control period [CP]/3-month washout period/6-month intervention period [IP]) or sequence 1-0 (6-month IP/3-month washout period/6-month CP). A surveillance screening program for Pa was implemented. Competing-risks regression models were built with death and discharge without the occurrence of ICU-acquired Pa infection (the primary outcome) as competing events. Models were adjusted for within-ICU correlation and patient- and ICU-level covariates. The Simpson diversity index (SDI) and transmission index (TI) of Pa isolates were derived from pulsed-field gel electrophoresis typing. RESULTS: Within recruited ICUs, the cumulative incidence and incidence rate of ICU-acquired Pa infections were 3.38% (55/1625) versus 3.44% (57/1658) and 3.31 versus 3.52 per 1000 patient-days at risk during the CP and IP, respectively. Multivariable models indicated that the intervention did not significantly change the cumulative incidence (subdistribution hazard ratio, .91; 95% confidence interval [CI], .49-1.67; P = .76) or rate (cause-specific hazard ratio, 1.36; 95% CI, .71-2.63; P = .36) of the primary outcome. SDI and TI did not significantly differ between CP and IP. CONCLUSIONS: The addition of contact precautions to standard precautions for Pa-positive patients with a surveillance screening program does not significantly reduce ICU-acquired Pa infections in non-outbreak situations. Clinical Trials Registration. ISRCTN92710225.

Rifampicin and clarithromycin (extended release) versus rifampicin and streptomycin for limited Buruli ulcer lesions: a randomised, open-label, non-inferiority phase 3 trial.

BACKGROUND: Buruli ulcer is a neglected tropical disease caused by Mycobacterium ulcerans infection that damages the skin and subcutis. It is most prevalent in western and central Africa and Australia. Standard antimicrobial treatment with oral rifampicin 10 mg/kg plus intramuscular streptomycin 15 mg/kg once daily for 8 weeks (RS8) is highly effective, but streptomycin injections are painful and potentially harmful. We aimed to compare the efficacy and tolerability of fully oral rifampicin 10 mg/kg plus clarithromycin 15 mg/kg extended release once daily for 8 weeks (RC8) with that of RS8 for treatment of early Buruli ulcer lesions. METHODS: We did an open-label, non-inferiority, randomised (1:1 with blocks of six), multicentre, phase 3 clinical trial comparing fully oral RC8 with RS8 in patients with early, limited Buruli ulcer lesions. There were four trial sites in hospitals in Ghana (Agogo, Tepa, Nkawie, Dunkwa) and one in Benin (Pobè). Participants were included if they were aged 5 years or older and had typical Buruli ulcer with no more than one lesion (caterories I and II) no larger than 10 cm in diameter. The trial was open label, and neither the investigators who took measurements of the lesions nor the attending doctors were masked to treatment assignment. The primary clinical endpoint was lesion healing (ie, full epithelialisation or stable scar) without recurrence at 52 weeks after start of antimicrobial therapy. The primary endpoint and safety were assessed in the intention-to-treat population. A sample size of 332 participants was calculated to detect inferiority of RC8 by a margin of 12%. This study was registered with ClinicalTrials.gov, NCT01659437. FINDINGS: Between Jan 1, 2013, and Dec 31, 2017, participants were recruited to the trial. We stopped recruitment after 310 participants. Median age of participants was 14 years (IQR 10-29) and 153 (52%) were female. 297 patients had PCR-confirmed Buruli ulcer; 151 (51%) were assigned to RS8 treatment, and 146 (49%) received oral RC8 treatment. In the RS8 group, lesions healed in 144 (95%, 95% CI 91 to 98) of 151 patients, whereas lesions healed in 140 (96%, 91 to 99) of 146 patients in the RC8 group. The difference in proportion, -0·5% (-5·2 to 4·2), was not significantly greater than zero (p=0·59), showing that RC8 treatment is non-inferior to RS8 treatment for lesion healing at 52 weeks. Treatment-related adverse events were recorded in 20 (13%) patients receiving RS8 and in nine (7%) patients receiving RC8. Most adverse events were grade 1-2, but one (1%) patient receiving RS8 developed serious ototoxicity and ended treatment after 6 weeks. No patients needed surgical resection. Four patients (two in each study group) had skin grafts. INTERPRETATION: Fully oral RC8 regimen was non-inferior to RS8 for treatment of early, limited Buruli ulcer and was associated with fewer adverse events. Therefore, we propose that fully oral RC8 should be the preferred therapy for early, limited lesions of Buruli ulcer. FUNDING: WHO with additional support from MAP International, American Leprosy Missions, Fondation Raoul Follereau France, Buruli ulcer Groningen Foundation, Sanofi-Pasteur, and BuruliVac.

Broadband electron paramagnetic resonance of a molecular spin triangle.

We built a broadband Electron Paramagnetic Resonance (EPR) spectrometer capable of field- and frequency sweep experiments under field-, microwave amplitude- and microwave frequency-modulation detection modes (HM, AM, and FM, respectively). The spectrometer is based on a coplanar waveguide (CPW) architecture, with the sample being deposited on top of the transmission line. We tested the functionality of this spectrometer by measuring a standard 2,2-diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl (DPPH) sample, and complex (NnBu4)2[Cu3(µ3-Cl)2(µ-pz)3Cl3] (1), drop-casted on the CPW. Complex 1 had been previously studied by conventional X-band EPR spectroscopy (Chem. - Eur. J., 2020, 26, 12769-1784), and comparison with the past studies validated the functionality of the spectrometer and confirmed the stability of the sample upon deposition. Moreover, our results highlighted the importance of surface effects and of the orientation of the microwave magnetic component B1 on the lineshapes of the recorded spectra.

Usefulness of point-of-care multiplex PCR to rapidly identify pathogens responsible for ventilator-associated pneumonia and their resistance to antibiotics: an observational study.

BACKGROUND: The use of multiplex PCR to shorten time to identification of pathogens and their resistance mechanisms for patients with ventilator-associated pneumonia (VAP) is attractive, but poorly studied. The multiplex PCR-based Unyvero pneumonia cartridge assay can directly identify 20 bacteria and one fungus, amongst the most frequently causing VAP, and 19 of their resistance markers in clinical specimens (bronchoalveolar lavage or tracheal aspirate), with a turnaround time of 4-5 h. We performed this study to evaluate the concordance between the multiplex PCR-based Unyvero pneumonia cartridge assay and conventional microbiological techniques to identify pathogens and their resistance mechanisms in patients with VAP. METHODS: All patients suspected of having VAP (January 2016 to January 2019), who underwent fiberoptic bronchoscopy with bronchoalveolar lavage fluid (BALF) and whose BALF microscopy examination revealed intracellular bacteria, were included. BALF conventional cultures (gold standard), antimicrobial susceptibility testing and processing for the Unyvero pneumonia cartridge were done. Culture and Unyvero results were compared. RESULTS: Compared to cultures of the 93 samples processed for both techniques, Unyvero correctly identified pathogens in 68 (73%) proven VAP episodes, was discordant for 25 (27%), detected no pathogen in 11 and overdetected a not otherwise found pathogen in six. For the eight remaining discordant results, the pathogen responsible for VAP was not included in the Unyvero cartridge panel or it grew at a non-significant level in culture. Amongst the 31 (33%) resistance mechanism discordances observed, 22 were resistance detection failures and 24 concerned Pseudomonas aeruginosa. CONCLUSIONS: Compared to conventional microbiological cultures, the Unyvero pneumonia cartridge had poor diagnostic performance: it correctly identified pathogens and their resistance mechanisms in 73% and 67% of VAP cases, respectively. The lack of performance on the resistance mechanism was more pronounced when the pathogen detected was a Pseudomonas aeruginosa.

HDL from an Alzheimer's disease perspective.

PURPOSE OF REVIEW: We review current knowledge regarding HDL and Alzheimer's disease, focusing on HDL's vasoprotective functions and potential as a biomarker and therapeutic target for the vascular contributions of Alzheimer's disease. RECENT FINDINGS: Many epidemiological studies have observed that circulating HDL levels associate with decreased Alzheimer's disease risk. However, it is now understood that the functions of HDL may be more informative than levels of HDL cholesterol (HDL-C). Animal model studies demonstrate that HDL protects against memory deficits, neuroinflammation, and cerebral amyloid angiopathy (CAA). In-vitro studies using state-of-the-art 3D models of the human blood-brain barrier (BBB) confirm that HDL reduces vascular Aß accumulation and attenuates Aß-induced endothelial inflammation. Although HDL-based therapeutics have not been tested in clinical trials for Alzheimer's disease , several HDL formulations are in advanced phase clinical trials for coronary artery disease and atherosclerosis and could be leveraged toward Alzheimer's disease . SUMMARY: Evidence from human studies, animal models, and bioengineered arteries supports the hypothesis that HDL protects against cerebrovascular dysfunction in Alzheimer's disease. Assays of HDL functions relevant to Alzheimer's disease may be desirable biomarkers of cerebrovascular health. HDL-based therapeutics may also be of interest for Alzheimer's disease, using stand-alone or combination therapy approaches.

Poor Performance of Rapid Molecular Tests to Define Eligibility for the Shortcourse Multidrug-resistant Tuberculosis Regimen.

The World Health Organization recommends shortcourse regimen (SCR) to treat multidrug resistant tuberculosis for patients with strains susceptible by line-probe assays (LPAs) to second-line drugs. Our retrospective study shows LPAs have suboptimal specificity in predicting eligibility for SCR; a quarter of eligible patients would receive inadequate therapy with SCR.

Polyanisotropic Magnetoelectric Coupling in an Electrically Controlled Molecular Spin Qubit.

Two molecular spin qubits are studied with pulsed electron paramagnetic resonance (EPR) spectroscopy under electric fields to assess their magnetoelectric (ME) couplings and electric spin control. [Fe3O(PhCOO)6(py)3]ClO4·py (Fe3) is characterized by strong Dzyaloshinskii-Moriya interactions (DMI) which induce important magnetoanisotropy, whereas the DMI in [Cr3O(PhCOO)6(py)3]ClO4·0.5py (Cr3) is 1-2 orders of magnitude weaker. Fe3 is observed to demonstrate a clear ME effect, whose intensity shows an unprecedented dependence on the molecular orientation within the electric field E (electroanisotropy) and on the relative orientations of the molecular z axis, the Zeeman field B0 and E (magnetoelectric anisotropy). The electric control in Fe3 is shown to be coherent, and the ME effect exhibits complex dynamics characterized by saturation and oscillatory effects. On the other hand, Cr3 exhibits no discernible ME effect, which correlates well with its negligible DMI.

Erwinia billingiae as Unusual Cause of Septic Arthritis, France, 2017.

In 2017 in France, we treated a patient with knee septic arthritis caused by Erwinia billingiae after trauma involving a palm tree. This rare pathogen could only be identified through 16S rRNA gene sequencing. For bacterial infections after injuries with plants, 16S rRNA gene sequencing might be required for species identification.

Outcomes of Bedaquiline Treatment in Patients with Multidrug-Resistant Tuberculosis.

Bedaquiline is recommended by the World Health Organization for the treatment of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB). We pooled data from 5 cohorts of patients treated with bedaquiline in France, Georgia, Armenia, and South Africa and in a multicountry study. The rate of culture conversion to negative at 6 months (by the end of 6 months of treatment) was 78% (95% CI 73.5%-81.9%), and the treatment success rate was 65.8% (95% CI 59.9%-71.3%). Death rate was 11.7% (95% CI 7.0%-19.1%). Up to 91.1% (95% CI 82.2%-95.8%) of the patients experienced >1 adverse event, and 11.2% (95% CI 5.0%-23.2%) experienced a serious adverse event. Lung cavitations were consistently associated with unfavorable outcomes. The use of bedaquiline in MDR and XDR TB treatment regimens appears to be effective and safe across different settings, although the certainty of evidence was assessed as very low.

Risk factors for carbapenem-resistant Enterobacteriaceae infections: a French case-control-control study.

This study aimed to assess characteristics associated with infections due to carbapenem-resistant Enterobacteriaceae (CRE), producing (CPE) or not producing (non-CPE) carbapenemase, among hospitalised patients in 2014-2016 in France. Case-patients with CRE were compared to two control populations. In multivariate analysis comparing 160 CRE cases to 160 controls C1 (patients with a clinical sample positive for carbapenem-susceptible Enterobacteriaceae), five characteristics were linked to CRE: male gender (OR = 1.9; 95% CI = 1.3-3.4), travel in Asia (OR = 10.0; 95% CI = 1.1-91.2) and hospitalisation in (OR = 2.4; 95% CI = 1.3-4.4) or out of (OR = 4.4; 95% CI = 0.8-24.1) France in the preceding 12 months, infection in the preceding 3 months (OR = 3.0; 95% CI = 1.5-5.9), and antibiotic receipt between admission and inclusion (OR = 1.9; 95% CI = 1.0-3.3). In multivariate analysis comparing 148 CRE cases to 148 controls C2 [patients with culture-negative sample(s)], four characteristics were identified: prior infection (OR = 3.3; 95% CI = 1.6-6.8), urine drainage (OR = 3.0; 95% CI = 1.5-6.1) and mechanical ventilation (OR = 3.7; 95% CI = 1.1-13.0) during the current hospitalisation, and antibiotic receipt between admission and inclusion (OR = 6.6; 95% CI = 2.8-15.5). Univariate analyses comparing separately CPE cases to controls (39 CPE vs C1 and 36 CPE vs C2) and non-CPE cases to controls (121 non-CPE vs C1 and 112 non-CPE vs C2), concomitantly with comparison of CPE to non-CPE cases showed that only CPE cases were at risk of previous travel and hospitalisation abroad. This study shows that, among CRE, risk factors are different for CPE and non-CPE infection, and suggests that question patients about their medical history and lifestyle should help for early identification of patients at risk of CPE among patients with CRE.

Molecular epidemiology of Pseudomonas aeruginosa isolated from infected ICU patients: a French multicenter 2012-2013 study.

Although Pseudomonas aeruginosa has a non-clonal epidemic population structure, recent studies have provided evidence of the existence of epidemic high-risk clones. The aim of this study was to assess the molecular epidemiology of P. aeruginosa isolates responsible for infections in French ICUs, regardless of resistance patterns. For a 1-year period, all non-duplicate P. aeruginosa isolated from bacteremia and pulmonary infections in ten adult ICUs of six French university hospitals were characterized by antimicrobial susceptibility testing and genotyping (MLST and PFGE). We identified ß-lactamases with an extended spectrum phenotypically and by sequencing. The 104 isolates tested were distributed in 46 STs, of which 7 epidemic high-risk (EHR) clones over-represented: ST111, ST175, ST235, ST244, ST253, ST308, and ST395. Multidrug-resistant (MDR) isolates mostly clustered in these EHR clones, which frequently spread within hospitals. Only one ST233 isolate produced the carbapenemase VIM-2. PFGE analysis suggests frequent intra-hospital cross-transmission involving EHR clones. For ST395 and ST308, we also observed the progression from wild-type to MDR resistance pattern within the same PFGE pattern. Molecular epidemiology of P. aeruginosa in French ICUs is characterized by high clonal diversity notably among antimicrobial susceptible isolates and the over-representation of EHR clones, particularly within MDR isolates, even though multidrug resistance is not a constant inherent trait of EHR clones.

Relevance of Dzyaloshinskii-Moriya spectral broadenings in promoting spin decoherence: a comparative pulsed-EPR study of two structurally related iron(iii) and chromium(iii) spin-triangle molecular qubits.

Spectral broadenings due to Dzyaloshinskii-Moriya interactions (DMI) were assessed with respect to the decoherence they induce through increased spin-spin interactions, as the role of DMI in developing magnetoelectric spin-chirality qubits is gaining recognition. The structurally related spin triangles [Fe3O(PhCOO)6(py)3]ClO4·py (Fe3) and [Cr3O(PhCOO)6(py)3]ClO4·0.5py (Cr3) were studied as frozen py-d5 solutions with various pulsed Electron Paramagnetic Resonance (EPR) spectroscopy experiments, and under identical experimental conditions. Field-swept Hahn echo experiments revealed a match with continuous-wave (CW) spectra, while variable-temperature saturation/inversion recovery and Hahn echo decay experiments were used to extract the thermal evolutions of the spin-lattice relaxation and phase-memory times (T1 and Tm, respectively). Nutation experiments revealed Rabi oscillations demonstrating that the spins of the complexes could be coherently manipulated. Careful comparisons of Tm times confirmed hyperfine interactions with the magnetic nuclei of the metal ions as an intrinsic source of decoherence. Comparisons of Rabi damping times revealed that DMI-induced spectral broadenings play a discernible but moderate role as an extrinsic source of decoherence for the nutation experiments and that they are not particularly detrimental to spin manipulations.