Cefoxitin and imipenem are the sole recommended β-lactams for the treatment of Mycobacterium abscessus pulmonary infections. Here, we investigated whether one of these drugs displays superiority in ...terms of killing and intracellular activity. We have also evaluated whether the use of a β-lactamase inhibitor could improve their activity.
The impact of the β-lactamase BlaMab on the activity of β-lactams was assessed by comparing M. abscessus CIP104536 and its β-lactamase-deficient ΔblaMab derivative, as well as by using the β-lactamase inhibitor avibactam. The activity of cefoxitin, imipenem, amoxicillin and ceftaroline, alone and in various combinations including amikacin, was compared based on determination of time-kill curves and of intracellular proliferation in human macrophages.
Imipenem was superior to cefoxitin in both the time-kill and macrophage assays. Production of BlaMab limited the activity of imipenem. The combination of imipenem and amikacin was bactericidal against the ΔblaMab mutant. Deletion of blaMab extended the spectrum of β-lactams active against M. abscessus to include amoxicillin and ceftaroline. In the absence of BlaMab, amoxicillin was as active as imipenem. These drugs were more active than ceftaroline and cefoxitin was the least active. Avibactam increased the intracellular activity of ceftaroline, but inhibition of BlaMab was only partial, as previously reported for amoxicillin.
Evaluation of the killing and intracellular activities of β-lactams indicates that imipenem is superior to cefoxitin at clinically achievable drug concentrations. Inhibition of BlaMab could improve the efficacy of imipenem and extend the spectrum of drugs potentially useful to treat pulmonary infections.
Background
Necrozoospermia is a condition found in 0.2%–0.4% of male infertility cases. The causes of necrozoospermia are multiple: they can be related to testicular and/or post‐testicular damage. ...Additionally, these causes most often involve the production of reactive oxygen species (ROS) and/or sperm DNA fragmentation (SDF) which can reduce the chances of spontaneous pregnancy or affect the outcome of assisted reproductive technologies.
Objective
To focus on potential etiologies of necrozoospermia, its diagnosis and its therapeutic management especially before the employment of ICSI.
Methods
Authors searched PubMed/Medline, Web of Science, Cochrane Library, Google and Institutional websites for medical subheading terms and free text words referred to “necrozoospermia”, “sperm vitality”, “sperm viability”, SDF and “ICSI”.
Results
We identified 12 main etiologies of necrozoospermia responsible for either a decrease of sperm vitality, a mild, a moderate or a severe necrozoospermia. In case of a confirmed decreased vitality, a thorough check‐up should be conducted and if available, etiological treatment should be proposed. Therapeutic management could also include repeated ejaculations, drug treatments, the use of ICSI with ejaculated or surgically extracted spermatozoa in case of a non‐treatable necrozoospermia.
Discussion and conclusion
The potential causes of necrozoospermia should be investigated because many of them could be corrected, thus avoiding the use of ICSI. Moreover, if ICSI procedure remains necessary, the therapeutic management of necrozoospermia could also improve the chances of success by reducing oxidative stress and/or SDF.
Mycobacterium abscessus pulmonary infections are treated with a macrolide (clarithromycin or azithromycin), an aminoglycoside (amikacin), and a β-lactam (cefoxitin or imipenem). The triple ...combination is used without any β-lactamase inhibitor, even though M. abscessus produces the broad-spectrum β-lactamase BlaMab. We determine whether inhibition of BlaMab by avibactam improves the activity of imipenem against M. abscessus. The bactericidal activity of drug combinations was assayed in broth and in human macrophages. The in vivo efficacy of the drugs was tested by monitoring the survival of infected zebrafish embryos. The level of BlaMab production in broth and in macrophages was compared by quantitative reverse transcription-PCR and Western blotting. The triple combination of imipenem (8 or 32 μg/ml), amikacin (32 μg/ml), and avibactam (4 μg/ml) was bactericidal in broth (<0.1% survival), with 3.2- and 4.3-log10 reductions in the number of CFU being achieved at 72 h when imipenem was used at 8 and 32 μg/ml, respectively. The triple combination achieved significant intracellular killing, with the bacterial survival rates being 54% and 7% with the low (8 μg/ml) and high (32 μg/ml) dosages of imipenem, respectively. In vivo inhibition of BlaMab by avibactam improved the survival of zebrafish embryos treated with imipenem. Expression of the gene encoding BlaMab was induced (20-fold) in the infected macrophages. Inhibition of BlaMab by avibactam improved the efficacy of imipenem against M. abscessusin vitro, in macrophages, and in zebrafish embryos, indicating that this β-lactamase inhibitor should be clinically evaluated. The in vitro evaluation of imipenem may underestimate the impact of BlaMab, since the production of the β-lactamase is inducible in macrophages.
Two β-lactams, cefoxitin and imipenem, are part of the reference treatment for pulmonary infections with Mycobacterium abscessus. M. abscessus has recently been shown to produce a broad-spectrum ...β-lactamase, BlaMab, indicating that the combination of β-lactams with a BlaMab inhibitor may improve treatment efficacy. The objectives of this study were to evaluate the impact of BlaMab production on the efficacy of β-lactams in vitro and to assess the benefit of BlaMab inhibition on the activity of β-lactams intracellularly and in an animal model.
We analysed the mechanism and kinetics of BlaMab inactivation by avibactam, a non-β-lactam β-lactamase inhibitor currently in Phase III of development, in combination with ceftazidime for the treatment of serious infections due to Gram-negative bacteria. We then deleted the gene encoding BlaMab to assess the extent of BlaMab inhibition by avibactam based on a comparison of the impact of chemical and genetic inactivation. Finally, the efficacy of amoxicillin in combination with avibactam was evaluated in cultured human macrophages and in a zebrafish model of M. abscessus infection.
We showed that avibactam efficiently inactivated BlaMab via the reversible formation of a covalent adduct. An inhibition of BlaMab by avibactam was observed in both infected macrophages and zebrafish.
Our data identify avibactam as the first efficient inhibitor of BlaMab and strongly suggest that β-lactamase inhibition should be evaluated to provide improved therapeutic options for M. abscessus infections.
PurposeCongenital anomalies and intellectual disability (CA/ID) are a major diagnostic challenge in medical genetics-50% of patients still have no molecular diagnosis after a long and stressful ...diagnostic "odyssey." Solo clinical whole-exome sequencing (WES) was applied in our genetics center to improve diagnosis in patients with CA/ID.MethodsThis retrospective study examined 416 consecutive tests performed over 3 years to demonstrate the effectiveness of periodically reanalyzing WES data. The raw data from each nonpositive test was reanalyzed at 12 months with the most recent pipeline and in the light of new data in the literature. The results of the reanalysis for patients enrolled in the third year are not yet available.ResultsOf the 416 patients included, data for 156 without a diagnosis were reanalyzed. We obtained 24 (15.4%) additional diagnoses: 12 through the usual diagnostic process (7 new publications, 4 initially misclassified, and 1 copy-number variant), and 12 through translational research by international data sharing. The final yield of positive results was 27.9% through a strict diagnostic approach, and 2.9% through an additional research strategy.ConclusionThis article highlights the effectiveness of periodically combining diagnostic reinterpretation of clinical WES data with translational research involving data sharing for candidate genes.
•Treatments are limited in progressive advanced non-small cell lung cancer (NSCLC).•Carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) could be targeted.•High expression (HE) of ...CEACAM5 occurs in 25% of patients with nonsquamous NSCLC.•CEACAM5 HE is more prevalent with altered KRAS (35%; G12C 41%) vs wild-type (20%).•These findings support the development of CEACAM5-targeted antibody-drug conjugates.
CEACAM5 is a cell-surface glycoprotein expressed on epithelial cells of some solid tumors. Tusamitamab ravtansine (SAR408701), a humanized antibody-drug conjugate targeting CEACAM5, is in clinical development for nonsquamous non-small cell lung cancer (NSQ-NSCLC) with CEACAM5 high expression (HE), defined as membranous CEACAM5 immunohistochemistry staining at ≥ 2+ intensity in ≥ 50% of tumor cells.
We investigated correlations between CEACAM5 expression by immunohistochemistry, CEACAM5 protein expression by ELISA, and CEACAM5 RNA expression by RNA-seq in NSQ-NSCLC patient-derived xenograft (PDX) models, and tumor responses to tusamitamab ravtansine in these models. We assessed prevalence of CEACAM5 HE, clinicopathologic characteristics and molecular markers in patients with NSQ-NSCLC in clinical cohorts.
In a lung PDX set of 10 NSQ-NSCLC specimens, correlations between CEACAM5 by IHC, ELISA and RNA-seq ranged from 0.72 to 0.88. In a larger lung PDX set, higher H-scores were present in NSQ- (n = 93) vs SQ-NSCLC (n = 128) models, and in 12 of these NSQ-NSCLC models, more tumor responses to tusamitamab ravtansine occurred in CEACAM5 HE (5/8; 62.5%) versus moderate or negative expression (1/4; 25%), including 3 with KRAS mutations among the 6 responders. In clinical NSQ-NSCLC samples, CEACAM5 HE prevalence was (52/214; 24.3%) in primary tumors and (6/17; 35.3%) in metastases. In NSQ-NSCLC primary tumors, CEACAM5 HE prevalence was significantly higher in KRAS-altered versus wild-type (35.0% vs 19.5%; P = 0.028) and in programmed cell death ligand 1 (PD-L1) negative (tumor cells 0%)/low (1–49%) versus high (≥50%) (33.3%, 26.1%, 5.0%; P = 0.031), but not significantly different in EGFR-mutated versus wild-type (20.0% vs 25.7%, P = 0.626).
In NSQ-NSCLC tumors, CEACAM5 HE prevalence was 24.3% overall and was higher with KRAS altered and with PD-L1 negative/low tumors but similar regardless of EGFR mutation status. These findings support targeting CEACAM5 and the clinical development of tusamitamab ravtansine for patients with NSQ-NSCLC with CEACAM5 HE.
Foot‐and‐mouth disease (FMD) affects the livestock industry and socioeconomic sustainability of many African countries. The success of FMD control programs in Africa depends largely on understanding ...the dynamics of FMD virus (FMDV) spread. In light of the recent outbreaks of FMD that affected the North‐Western African countries in 2018 and 2019, we investigated the evolutionary phylodynamics of the causative serotype O viral strains all belonging to the East‐Africa 3 topotype (O/EA‐3). We analyzed a total of 489 sequences encoding the FMDV VP1 genome region generated from samples collected from 25 African and Western Asian countries between 1974 and 2019. Using Bayesian evolutionary models on genomic and epidemiological data, we inferred the routes of introduction and migration of the FMDV O/EA‐3 topotype at the inter‐regional scale. We inferred a mean substitution rate of 6.64 × 10−3 nt/site/year and we predicted that the most recent common ancestor for our panel of samples circulated between February 1967 and November 1973 in Yemen, likely reflecting the epidemiological situation in under sampled cattle‐exporting East African countries. Our study also reinforces the role previously described of Sudan and South Sudan as a frequent source of FMDVs spread. In particular, we identified two transboundary routes of O/EA‐3 diffusion: the first from Sudan to North‐East Africa, and from the latter into Israel and Palestine AT; a second from Sudan to Nigeria, Cameroon, and from there to further into West and North‐West Africa. This study highlights the necessity to reinforce surveillance at an inter‐regional scale in Africa and Western Asia, in particular along the identified migration routes for the implementation of efficient control measures in the fight against FMD.
The Institut Pasteur de Lille, in the north of France, has implemented a large, multidisciplinary health check, which aims to identify frailty in middle-aged caregivers. We aimed to construct an ...adapted frailty index of cumulative deficit (FI-CD) and study the associated factors, in particular socioeconomic factors.
The cross-sectional study included caregivers aged 45 to 65. A 34-item FI-CD including deficits adapted to a middle-aged population (related to cognition and autonomy, dietetics, physical activity, comorbidities, functional signs, lab values and paraclinical examinations) was constructed in accordance with standard procedures. It was calculated as a ratio of deficits present out of the total number of possible deficits, giving a continuous score between 0 and 1. Scores > 0.25 and > 0.4 were classified as frailty and severe frailty, respectively. Univariate and multivariate associations were studied using linear regressions.
One hundred and seventeen caregivers were included; among them, 111 were analyzed due to missing values. The mean FI-CD was 0.22 ± 0.08. Forty (36%) individuals were classified as frailty and three (2.7%) as severe frailty. In multivariate analysis, FI-CD was significantly associated with age (beta 95% confidence interval = 0.005 0.002; 0.009 per 1-year increase, p = 0.005) and social deprivation (beta = 0.054 0.007; 0.102, p = 0.025). A significant interaction was observed between and age and social deprivation (p = 0.036). The adjusted relationship between FI-CD and age was beta = 0.010 0.002; 0.019, p = 0.017 in precarious caregivers, and beta = 0.003 - 0.001; 0.007, p = 0.19 in non-precarious caregivers.
The study suggested that the 34-item FI-CD could have clinical utility in the management of middle-aged caregivers. Social deprivation appeared as an important factor associated with frailty, highlighting the importance of early care and social support for precarious caregivers.
The production of β-lactamases Bla(Mab) and BlaC contributes to β-lactam resistance in Mycobacterium abscessus and Mycobacterium tuberculosis, respectively. Ceftaroline was efficiently hydrolyzed by ...these enzymes. Inhibition of M. tuberculosis BlaC by clavulanate decreased the ceftaroline MIC from ≥ 256 to 16 to 64 μg/ml, but these values are clinically irrelevant. In contrast, the ceftaroline-avibactam combination should be evaluated against M. abscessus since it inhibited growth at lower and potentially achievable drug concentrations.
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