Publications by authors named "C Monteil"

103 Publications

The effect of camelina oil on vascular function in essential hypertensive patients with metabolic syndrome: A randomized, placebo-controlled, double-blind study.

Am J Clin Nutr 2021 Nov 15. Epub 2021 Nov 15.

Department of Pharmacology, Rouen University Hospital, 76000 Rouen, France.

Background: The effects of a dietary supplementation with the vegetable omega-3 α-linolenic acid (ALA) on cardiovascular homeostasis are unclear. In this context, it would be interesting to assess the effects of camelina oil.

Objective: This study aimed to assess the cardiovascular and metabolic effects of camelina oil in hypertensive patients with metabolic syndrome.

Methods: In a double-blind placebo-controlled randomized study, treated essential hypertensive patients with metabolic syndrome received during 6 months either cyclodextrin-complexed camelina oil containing ≈ 1.5 g ALA/day (n = 40), or an isocaloric placebo (n = 41), consisting in the same quantity of cyclodextrins and wheat starch. Anthropometric data, plasma lipids, glycemia, insulinemia, creatininemia, thiobarbituric acid reactive substances, high-sensitivity C-reactive protein, and n-3, n-6 and n-9 fatty acids in erythrocyte membranes were measured. Peripheral and central blood pressures, arterial stiffness, carotid intima-media thickness and brachial artery endothelium-dependent flow-mediated dilatation and endothelium-independent dilatation were assessed.

Results: Compared to placebo, camelina oil increased ALA (mean ± SD: 0 ± 0.04 vs. 0.08 ± 0.06%, P < 0.001), its elongation product eicosapentaenoic acid (EPA; 0 ± 0.5 vs. 0.16 ± 0.65%, P < 0.05), and the n-9 gondoic acid (0 ± 0.04 vs. 0.08 ± 0.04%, P < 0.001). No between-group difference was observed for cardiovascular parameters. However, changes in flow-mediated dilatation were associated with the magnitude of changes in EPA (r = 0.26, P = 0.03). Compared to placebo, camelina oil increased fasting glycemia (-0.2 ± 0.6 vs. 0.3 ± 0.5 mmol/L, P < 0.001) and homeostatic model assessment for insulin resistance (HOMA-IR; -0.8 ± 2.5 vs. 0.5 ± 0.9, P < 0.01) index, without affecting plasma lipids, or inflammatory and oxidative stress markers. Changes in HOMA-IR index were correlated with the magnitude of changes in gondoic acid (r = 0.32, P < 0.01). Nutritional intake remained similar between groups.

Conclusion: ALA supplementation with camelina oil did not improve vascular function but adversely affected glucose metabolism in hypertensive patients with metabolic syndrome Whether this adverse effect on insulin sensitivity is related to gondoic acid enrichment, remains to be elucidated.
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http://dx.doi.org/10.1093/ajcn/nqab374DOI Listing
November 2021

Ice nucleation in a Gram-positive bacterium isolated from precipitation depends on a polyketide synthase and non-ribosomal peptide synthetase.

ISME J 2021 Oct 23. Epub 2021 Oct 23.

School of Plant and Environmental Sciences, Virginia Tech, Blacksburg, VA, USA.

Earth's radiation budget and frequency and intensity of precipitation are influenced by aerosols with ice nucleation activity (INA), i.e., particles that catalyze the formation of ice. Some bacteria, fungi, and pollen are among the most efficient ice nucleators but the molecular basis of INA is poorly understood in most of them. Lysinibacillus parviboronicapiens (Lp) was previously identified as the first Gram-positive bacterium with INA. INA of Lp is associated with a secreted, nanometer-sized, non-proteinaceous macromolecule or particle. Here a combination of comparative genomics, transcriptomics, and a mutant screen showed that INA in Lp depends on a type I iterative polyketide synthase and a non-ribosomal peptide synthetase (PKS-NRPS). Differential filtration in combination with gradient ultracentrifugation revealed that the product of the PKS-NRPS is associated with secreted particles of a density typical of extracellular vesicles and electron microscopy showed that these particles consist in "pearl chain"-like structures not resembling any other known bacterial structures. These findings expand our knowledge of biological INA, may be a model for INA in other organisms for which the molecular basis of INA is unknown, and present another step towards unraveling the role of microbes in atmospheric processes.
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http://dx.doi.org/10.1038/s41396-021-01140-4DOI Listing
October 2021

Surging bloodstream infections and antimicrobial resistance during the first wave of COVID-19: a study in a large multihospital institution in the Paris region.

Int J Infect Dis 2021 Oct 22;114:90-96. Epub 2021 Oct 22.

Groupe hospitalo-universitaire APHP Sorbonne Université, Site Pitié-Salpêtrière, Laboratoire de Bactériologie-Hygiène and CIMI-Paris, Inserm U1135, Sorbonne Université, Paris, France. Electronic address:

Objectives: This study measured the impact of the first wave of COVID-19 pandemic (COVID-19) (March-April 2020) on the incidence of bloodstream infections (BSIs) at Assistance Publique - Hôpitaux de Paris (APHP), the largest multisite public healthcare institution in France.

Methods: The number of patient admission blood cultures (BCs) collected, number of positive BCs, and antibiotic resistance and consumption were analysed retrospectively for the first quarter of 2020, and also for the first quarter of 2019 for comparison, in 25 APHP hospitals (ca. 14 000 beds).

Results: Up to a fourth of patients admitted in March-April 2020 in these hospitals had COVID-19. The BSI rate per 100 admissions increased overall by 24% in March 2020 and 115% in April 2020, and separately for the major pathogens (Escherichia coli, Klebsiella pneumoniae, enterococci, Staphylococcus aureus, Pseudomonas aeruginosa, yeasts). A sharp increase in the rate of BSIs caused by microorganisms resistant to third-generation cephalosporins (3GC) was also observed in March-April 2020, particularly in K. pneumoniae, enterobacterial species naturally producing inducible AmpC (Enterobacter cloacae...), and P. aeruginosa. A concomitant increase in 3GC consumption occurred.

Conclusions: The COVID-19 pandemic had a strong impact on hospital management and also unfavourable effects on severe infections, antimicrobial resistance, and laboratory work diagnostics.
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http://dx.doi.org/10.1016/j.ijid.2021.10.034DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8531236PMC
October 2021

Validation of a Fast and Simple HPLC-UV Method for the Quantification of Adenosine Phosphates in Human Bronchial Epithelial Cells.

Molecules 2021 Oct 19;26(20). Epub 2021 Oct 19.

Normandie Univ, UNIROUEN, UNICAEN, ABTE, 76000 Rouen, France.

A new HPLC method for the simultaneous quantitative analysis of adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP) was developed and validated. ATP, ADP, and AMP were extracted from human bronchial epithelial cells with a rapid extraction procedure and separated with a C18 column (3 × 150 mm, 2.7 µm) using isocratic elution with a mobile phase consisting of 50 mM of potassium hydrogen phosphate (pH 6.80). The absorbance was monitored at 254 nm. The calibration curves were linear in 0.2 to 10 µM, selective, precise, and accurate. This method allowed us to quantify the nucleotides from two cell models: differentiated NHBE primary cells grown at the air-liquid interface (ALI) and BEAS-2B cell line. Our study highlighted the development of a sensitive, simple, and green analytical method that is faster and less expensive than other existing methods to measure ATP, ADP, and AMP and can be carried out on 2D and 3D cell models.
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http://dx.doi.org/10.3390/molecules26206324DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8540776PMC
October 2021

Toxicological impact of organic ultrafine particles (UFPs) in human bronchial epithelial BEAS-2B cells at air-liquid interface.

Toxicol In Vitro 2021 Oct 13;78:105258. Epub 2021 Oct 13.

Normandie Univ, UNIROUEN, UNICAEN ABTE, 76000 Rouen, France. Electronic address:

Air pollution has significant health effects worldwide, and airborne particles play a significant role in these effects. Ultrafine particles (UFPs) have an aerodynamic diameter of 0.1 μm or less, can penetrate deep into the respiratory tree, and are more toxic due to their large specific surface area, which should adsorb organic compounds. The aim of this study is to show the toxicological effects of UFPs with high organic content at low dose on BEAS-2B cells through at air-liquid interface (ALI) exposure using a Vitrocell® technology and a miniCAST (Combustion Aerosol Standard) generator. In conjunction with this approach, chemical analysis of particles and gas phase was performed to evaluate the presence of polycyclic aromatic hydrocarbons (PAHs). Chemical analyses confirmed the presence of PAHs in UFPs. With this experimental setup, exposure of the BEAS-2B cells induced neither cytotoxicity nor mitochondrial dysfunction. However, an increase of oxidative stress was observed, as assessed through Nrf2, NQO1, HO-1, CuZnSOD, MnSOD, and Catalase gene expression, together with significant induction of genes related to xenobiotic metabolism CYP1A1 and CYP1B1. Negative regulation of inflammatory genes expression (IL-6 and IL-8) was present three hours after the exposition to the UFPs. Taken together, this experimental approach, using repeatable conditions, should help to clarify the mechanisms by which organic UFPs induce toxicological effects.
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http://dx.doi.org/10.1016/j.tiv.2021.105258DOI Listing
October 2021
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