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Reynolds C, Ross C, Cullinan P, Blanc P. Silicosis initially presenting with empyema. Occup Med (Lond) 2024:kqae047. [PMID: 38856490 DOI: 10.1093/occmed/kqae047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2024] Open
Abstract
The current global outbreak of artificial stone silicosis is a recrudescence of a major occupational disease in the context of a novel exposure source. Respirable crystalline silica exposure, even without frank pneumoconiosis, is associated with an increased risk of respiratory infection. Empyema is a well-recognized complication of bacterial pneumonia; pneumonia among working-age adults, in turn, has been epidemiologically linked to occupational exposure to fumes and dust, including silica. A connection between empyema and silica dust inhalation has not been reported, however, whether through antecedent pneumonia or another mechanism. We describe a case of silicosis initially presenting with empyema in a 31-year-old Computerized Numerical Control stone-cutting machine operator who had heavy exposure to artificial stone and other rock dust.
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Brun A, Klein C, Capon G, Alezra E, Estrade V, Blanc P, Bernhard JC, Bladou F, Robert G. Switching from the transrectal to the transperineal route: A single center experience. THE FRENCH JOURNAL OF UROLOGY 2024; 34:102519. [PMID: 37777435 DOI: 10.1016/j.purol.2023.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 08/14/2023] [Accepted: 09/07/2023] [Indexed: 10/02/2023]
Abstract
INTRODUCTION This study aimed to evaluate the feasibility of switching from transrectal to transperineal prostate biopsy (TPPBx) by urologists with no previous experience with TPPBx. Material A monocentric clinical study with exhaustive and consecutive inclusions was conducted between January and November 2021, including 105 consecutive patients who underwent TPPBx performed by two senior urologists with no previous experience of TPPBx (GR, FB). Biopsies were performed under local anesthesia (LA) without antibioprophylaxis. The main objective was to assess the safety of this procedure. Adverse events were classified according to the Clavien-Dindo score. The secondary objectives were to assess the level of pain experienced during the different steps of the procedure using a numerating rating scale (NRS), the rate of clinically significant prostate cancer (csPCa) detected, and the level of anxiety using the Hospital Anxiety and Depression Scale (HAD). RESULTS No major complications (Clavien-Dindo score≥3) were reported. One patient presented with acute urinary retention (1%) and a urinary tract infection (1%). Other adverse events were hematuria (43%), hemospermia (23%), rectal bleeding (1%), perineal hematoma (3%), persistent perineal pain (5%), and de novo erectile dysfunction (2%). The median level of pain on NRS for the procedure was 2.00 (IQ: 1.00-4.00); it was 3.00 (IQ: 2.00-5.00) during LA and 3.00 (IQ: 2.00-5.00) during punctions. In anxious patients (HAD score>10), the level of pain during the procedure was 2.5 (IQ: 2.00-3.00). Overall, csPCa was detected in 63%. CONCLUSION TPPBx under LA without antibioprophylaxis provides few complications, an acceptable pain threshold, and a satisfactorily rate of csPCa detection, even if performed by urologists with no previous experience of TPPBx. LEVEL OF EVIDENCE: 3
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Brun A, Klein C, Capon G, Alezra E, Estrade V, Blanc P, Bernhard J, Bladou F, Robert G. Swich to transperineal prostate biopsies: A single-center experience. Eur Urol 2023. [DOI: 10.1016/s0302-2838(23)00344-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Bahans C, Dallocchio A, Tran A, Dubos F, Soto B, Schoder G, Blanc P, Messager V, Demonchy D, Labrunie A, Garnier F, Guigonis V. The position during urine sample collection from young precontinent children through a bag does not limit contamination rates: Results from a randomized controlled trial: Does infant position influence quality of urine collection? Arch Pediatr 2022; 29:359-363. [PMID: 35513967 DOI: 10.1016/j.arcped.2022.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 02/10/2022] [Accepted: 03/26/2022] [Indexed: 11/24/2022]
Abstract
AIM Despite its limitation, bag collection is still widely used for a preliminary urine screening test in non-toilet-trained children suspected of febrile urinary tract infection. A previous study conducted by our group raised the hypothesis that the absence of direct contact between urine and the perinea during urine collection could limit urine contamination by perineal flora. The aim of this study was to evaluate the impact of the patient's position during urine collection (upright standing position versus free position) on the rate of contaminated urine samples in non-toilet-trained children with suspected febrile urinary tract infection. METHODS This prospective, randomized, controlled study took place in seven pediatric emergency departments. Two groups were compared: the intervention group (infants held in an upright standing position during urination) and the control group (free position during urination). RESULTS Among the 800 pediatric patients randomized to the study, 124 had a urine culture, 60 in the intervention group and 64 in the control group. Among the 124 urine cultures, 12 (9.7%) were contaminated: eight (13.3%) in the intervention group and four (6.3%) in the control group (p = 0.1824). CONCLUSION The results show that the patient's position does not have a significant impact on the quality of urine samples collected by bag.
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Seijo L, Smith P, Greenland J, Gao Y, Kolaitis N, Venado A, Hays S, Thakur N, Kukreja J, Leard L, Golden J, Shah R, Kleinhenz M, Perez A, Trinh B, Betancourt L, Medikonda N, Calabrese D, Blanc P, Katz P, Singer J. Worsening in the Lung Transplant-Valued Life Activities Scale is Associated with Mortality in Lung Transplant Recipients. J Heart Lung Transplant 2022. [DOI: 10.1016/j.healun.2022.01.1344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Margue G, Debard C, Michiels C, Dupitout L, Alezra E, Estrade V, Blanc P, Capon G, Robert G, Bladou F, Bernhard J. Tumorectomies rénales multiples, robot-assistées sans clampage et guidées par modélisation 3D. Prog Urol 2021. [DOI: 10.1016/j.purol.2021.08.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Margue G, Michiels C, Allenet C, Dupitout L, Ricard S, Blanc P, Alerzra E, Estrade V, Capon G, Bladou F, Robert G, Grenier N, Bernhard J. Faisabilité des néphrectomies partielles robot-assistées de rattrapage après échec de traitement ablatif (Étude UROCCR–62). Prog Urol 2021. [DOI: 10.1016/j.purol.2021.08.125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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de Hauteclocque A, Michiels C, Sarrazin J, Faessel M, Percot M, Le Paih JP, Guillaume A, Alezra E, Dupitout L, Vuong N, Grenier N, Capon G, Blanc P, Bensadoun H, Robert G, Bladou F, Ferriere J, Bos F, Estrade V, Bernhard JC. Three-dimensional printing technology to create a high-fidelity ureteroscopy simulator: Development and evaluation. Eur Urol 2021. [DOI: 10.1016/s0302-2838(21)01347-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Margue G, Percot M, Dupitout L, Michiels C, Blanc P, Alezra E, Estrade V, Capon G, Bladou F, Robert G, Grenier N, Bernhard J. Feasibility of salvage robotic partial nephrectomy after ablative treatment failure (UroCCR-62 study). Eur Urol 2021. [DOI: 10.1016/s0302-2838(21)00944-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Gobinet L, Tesi L, Vuong N, Mosillo L, Percot M, Dupitout L, Simeon H, Blanc P, Alezra E, Estrade V, Capon G, Bladou F, Robert G, Gross Goupil M, Bernhard JC. Monocentric experience of Robot-assisted radical nephrectomy with vena cava thrombectomy: Technique and results. Eur Urol 2021. [DOI: 10.1016/s0302-2838(21)01631-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Maheshwari J, Greenland J, Gao Y, Hays S, Katz P, Blanc P, Kolaitis N, Golden J, Kukreja J, Shah R, Leard L, Trinh B, Covinsky K, Calabrese D, Venado A, Huang C, Kleinhenz M, Sutter N, Tietje-Ulrich G, Singer J. Frailty is Associated with Subsequent Development of Chronic Lung Allograft Dysfunction Following Lung Transplantation. J Heart Lung Transplant 2021. [DOI: 10.1016/j.healun.2021.01.856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Mebroukine S, Chauveau B, Boulenger de Hauteclocque A, Percot M, Dupitout L, Blanc P, Alezra E, Estrade V, Bensadoun H, Ravaud A, Bladou F, Robert G, Ferrière J, Yacoub M, Gross-Goupil M, Bernhard J. Néphrectomie partielle robot-assistée après immunothérapie : faisabilité et partage d’expérience. Prog Urol 2020. [DOI: 10.1016/j.purol.2020.08.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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De Hauteclocque A, Michiels C, Sarrazin J, Faessel M, Percot M, Vuong N, Guillaume A, Le Paih J, Grenier N, Capon G, Blanc P, Alezra E, Bensadoun H, Robert G, Bladou F, Ferrière J, Bos F, Estrade V, Bernhard J. Utilisation de la technologie d’impression 3D pour créer un simulateur haute-fidélité d’urétéroscopie : développement et évaluation. Prog Urol 2020. [DOI: 10.1016/j.purol.2020.07.190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Allenet C, Klein C, Dupitout L, Percot M, Simeon H, Blanc P, Alezra E, Estrade V, Capon G, Bensadoun H, Bladou F, Robert G, Ferriere J, Bernhard J. Impact pronostique des rapports neutrophiles/lymphocytes préopératoire et postopératoire dans le cancer du rein de stade localisé (UroCCR no 61). Prog Urol 2020. [DOI: 10.1016/j.purol.2020.07.207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Dargent J, Lepage S, Carandina S, Blanc P, Breton C. Étude des agrafeuses laparoscopiques linéaires de la société REACH Surgical sur la sleeve gastrectomie en France. ACTA ACUST UNITED AC 2020. [DOI: 10.3166/obe-2020-0089] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Les interventions bariatriques laparoscopiques faisant usage d’agrafeuses linéaires sont devenues de plus en plus populaires en France, et représentent plus de 90 % du nombre total des procédures bariatriques, soit plus de 36 000 annuellement. La sleeve gastrectomie et le by-pass gastrique sont les plus réalisés aujourd’hui. Concernant les dispositifs concurrents des deux sociétés les mieux établies (Medtronic et Ethicon), il y a un manque de résultats publiés. Un essai a été conduit avec une nouvelle génération d’agrafeuses linéaires endoscopiques créées par une société chinoise (REACH Surgical) dans quatre centres en France (Lyon, Bourgoin, Toulon et Saint-Étienne) et cinq opérateurs différents. Trente-six sleeve gastrectomies ont été réalisées de octobre 2019 à février 2020 (34 primaires et deux secondaires), 32 femmes et quatre hommes, âge moyen : 42 ans, poids : 112 kg, IMC : 40,4 kg/m2. De 0 à 5, la note moyenne sur l’ergonomie a été de 4, et pour la sécurité 4,5. Il n’y a pas eu d’événements indésirables à 48 heures, et un à J4 (abcès sous-phrénique, pas de fistule digestive). L’impression générale a été celle d’un dispositif sûr et efficace.
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Miserazzi A, Perrigault M, Sow M, Gelber C, Ciret P, Lomenech AM, Dalens JM, Weber C, Le Floch S, Lacroix C, Blanc P, Massabuau JC. Proteome changes in muscles, ganglia, and gills in Corbicula fluminea clams exposed to crude oil: Relationship with behavioural disturbances. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2020; 223:105482. [PMID: 32371337 DOI: 10.1016/j.aquatox.2020.105482] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 03/23/2020] [Accepted: 03/25/2020] [Indexed: 06/11/2023]
Abstract
The use of online remote control for 24/7 behavioural monitoring can play a key role in estimating the environmental status of aquatic ecosystems. Recording the valve activity of bivalve molluscs is a relevant approach in this context. However, a clear understanding of the underlying disturbances associated with behaviour is a key step. In this work, we studied freshwater Asian clams after exposure to crude oil (measured concentration, 167 ± 28 μg·L-1) for three days in a semi-natural environment using outdoor artificial streams. Three complementary approaches to assess and explore disturbances were used: behaviour by high frequency non-invasive (HFNI) valvometry, tissue contamination with polycyclic aromatic hydrocarbons (PAH), and proteomic analysis. Two tissues were targeted: the pool adductor muscles - retractor pedal muscle - cerebral and visceral ganglia, which is the effector of any valve movement and the gills, which are on the frontline during contamination. The behavioural response was marked by an increase in valve closure-duration, a decrease in valve opening-amplitude and an increase in valve agitation index during opening periods. There was no significant PAH accumulation in the muscle plus nervous ganglia pool, contrary to the situation in the gills, although the latter remained in the low range of data available in literature. Major proteomic changes included (i) a slowdown in metabolic and/or cellular processes in muscles plus ganglia pool associated with minor toxicological effect and (ii) an increase of metabolic and/or cellular processes in gills associated with a greater toxicological effect. The nature of the proteomic changes is discussed in terms of unequal PAH distribution and allows to propose a set of explanatory mechanisms to associate behaviour to underlying physiological changes following oil exposure. First, the first tissues facing contaminated water are the inhalant siphon, the mantle edge and the gills. The routine nervous activity in the visceral ganglia should be modified by nervous information originating from these tissues. Second, the nervous activity in the visceral ganglia could be modified by its own specific contamination. Third, a decrease in nervous activity of the cerebral ganglia close to the mouth, including some kind of narcosis, could contribute to a decrease in visceral ganglia activity via a decrease or blockage of the downward neuromodulation by the cerebro-visceral connective. This whole set of events can explain the decrease of metabolic activity in the adductor muscles, contribute to initiate the catch mechanism and then deeply modify the valve behaviour.
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Blanc P, Breton C, Kuperas C. Robotic Roux-en-Y gastric bypass with hand sewn anastomosis (with video). J Visc Surg 2020; 157:157-158. [PMID: 32241641 DOI: 10.1016/j.jviscsurg.2020.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Miserazzi A, Sow M, Gelber C, Charifi M, Ciret P, Dalens JM, Weber C, Le Floch S, Lacroix C, Blanc P, Massabuau JC. Asiatic clam Corbicula fluminea exhibits distinguishable behavioural responses to crude oil under semi-natural multiple stress conditions. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2020; 219:105381. [PMID: 31869578 DOI: 10.1016/j.aquatox.2019.105381] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 12/05/2019] [Accepted: 12/05/2019] [Indexed: 06/10/2023]
Abstract
Aquatic ecosystems are subject to many anthropogenic disturbances, and understanding their possible impacts is a real challenge. Developing approaches based on the behaviour of bivalve mollusks, an integrating marker of the state of the organisms, and therefore of their environment, is relevant, whether within a natural ecosystem or an ecosystem subject to industrial activities. The main objective of this study was to identify by HFNI Valvometry a reliable and reproducible clam behavioural response in the presence of crude oil in a multistress context. To closely replicate actual field conditions, Corbicula fluminea was exposed in outdoor artificial streams that were subject to natural variations and were continuously fed by fresh water from the Gave de Pau (S.W. France). After a period of 26 days in these artificial streams, the clams (n = 14-16 per condition) were separately exposed for 10 days to crude oil alone, crude oil and barium, crude oil and noise pollution, crude oil and turbidity pulses, barium alone, noise pollution alone, turbidity pulses alone or natural changes alone. The secondary objective was to characterize the accumulation of polycyclic aromatic hydrocarbons (PAH) in 3 tissues (gills, adductor muscles and foot) in clams exposed for 10 days to crude oil alone or under multistress conditions (n = 5 clams per condition) and then to compare the accumulation and behaviour of clams under these conditions. The response of clams to crude oil alone or under multistress conditions was visually and statistically significant and not confounded by the other disturbances tested, despite large variations in water temperature. In the presence of crude oil, the behaviour of clams was characterized by an increase in valve-closure duration, a decrease in valve-opening amplitude and an increase in valve agitation index. In the presence of crude oil, the clam behaviour showed no direct relationship with PAH accumulation in the gills, adductor muscles or foot, although hypothetical mechanisms are discussed. This work supports the growing interest in studying the behaviour of bivalve mollusks in the context of biomonitoring of the aquatic environment surrounding oil facilities.
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De Hauteclocque A, Michiels C, Sarrazin J, Faessel M, Mosillo L, Percot M, Blanc P, Bensadoun H, Bladou F, Robert G, Capon G, Estrade V, Ferrière J, Bos F, Gill I, Bernhard J. Intérêt de modèles tridimensionnels virtuels et physiques pour évaluation de la complexité tumorale rénale et la planification opératoire des néphrectomies partielles (étude UroCCR-63 : 3D-planning). Prog Urol 2019. [DOI: 10.1016/j.purol.2019.08.238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Debard C, Bernhard J, Michiels C, Nam-son V, Le Quellec A, Blanc P, Capon G, Robert G, Bensadoun H, Ferrière J, Bladou F. Néphrectomie partielle de rattrapage robot-assistée après échec de cryothérapie. Prog Urol 2019. [DOI: 10.1016/j.purol.2019.08.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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De Hauteclocque A, Michiels C, Sarrazin J, Faessel M, Mosillo L, Percot M, Blanc P, Bensadoun H, Bladou F, Robert G, Capon G, Estrade V, Ferrière J, Bos F, Bernhard J. La modélisation 3D, un support efficace de l’information-patient avant chirurgie rénale. (Étude UroCCR-39 : Rein-3D-Print). Prog Urol 2019. [DOI: 10.1016/j.purol.2019.08.240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Perez A, Hays S, Gao Y, Soong A, Kleinhenz M, Leard L, Kukreja J, Venado A, Golden J, Shah R, Blanc P, Greenland J, Singer J. High Lung Allocation Scores Do Not Preclude Improvement in Health-Related Quality of Life after Lung Transplantation. J Heart Lung Transplant 2019. [DOI: 10.1016/j.healun.2019.01.557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Blanc P, Berjeb N, Siam Tsieu V, Boussuges A, Maunier S. Prevalence of iron deficiency in patients with chronic heart failure admitted in a Cardiac Rehabilitation Center in Reunion Island. ARCHIVES OF CARDIOVASCULAR DISEASES SUPPLEMENTS 2019. [DOI: 10.1016/j.acvdsp.2018.10.252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Blanc P, Berjeb N, Siam Tsieu V, Boussuges A, Maunier S. A 6-week multidisciplinary tailored Cardiac Rehabilitation Program is able to improve Left-Ventricular Ejection Fraction in patients with Chronic Heart Failure. ARCHIVES OF CARDIOVASCULAR DISEASES SUPPLEMENTS 2019. [DOI: 10.1016/j.acvdsp.2018.10.250] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Blanc P, Burnol A, Marty N, Hellal J, Guérin V, Laperche V. Methylmercury complexes: Selection of thermodynamic properties and application to the modelling of a column experiment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 621:368-375. [PMID: 29190560 DOI: 10.1016/j.scitotenv.2017.11.259] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 11/22/2017] [Accepted: 11/22/2017] [Indexed: 06/07/2023]
Abstract
Complexation with methyl groups produces the most toxic form of mercury, especially because of its capacity to bioconcentrate in living tissues. Understanding and integrating methylation and demethylation processes is of the utmost interest in providing geochemical models relevant for environmental assessment. In a first step, we investigated methylation at equilibrium, by selecting the thermodynamic properties of different complexes that form in the chemical system Hg-SO3-S-Cl-C-H2O. The selection included temperature dependencies of the equilibrium constants when available. We also considered adsorption and desorption reactions of both methylated and non-methylated mercury onto mineral surfaces. Then we assessed the kinetics of methylation by comparing a dedicated column experiment with the results of a geochemical model, including testing different methylation and demethylation kinetic rate laws. The column system was a simple medium: silicic sand and iron hydroxides spiked with a mercury nitrate solution. The modelling of methylmercury production with two different rate laws from the literature is bracketing the experimental results. Dissolved mercury, iron and sulfate concentrations were also correctly reproduced. The internal evolution of the column was also correctly modeled, including the precipitation of mackinawite (FeS) and the evolution of dissolved iron. The results validate the conceptual model and underline the capacity of geochemical models to reproduce some processes driven by bacterial activity.
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