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1.
Hum Reprod ; 36(4): 1032-1042, 2021 03 18.
Article in English | MEDLINE | ID: mdl-33421069

ABSTRACT

STUDY QUESTION: Do plastic laboratory consumables and cell culture media used in ART contain bisphenols? SUMMARY ANSWER: The majority of human embryo culture media assessed contained bisphenol S close to the nanomolar concentration range, while no release of bisphenols by plastic consumables was detected under routine conditions. WHAT IS KNOWN ALREADY: The deleterious effect of the endocrine disruptor bisphenol A (BPA) on female fertility raised concerns regarding ART outcome. BPA was detected neither in media nor in the majority of plastic consumables used in ART; however, it might have already been replaced by its structural analogs, including bisphenol S (BPS). STUDY DESIGN, SIZE, DURATION: Seventeen plastic consumables and 18 cell culture and ART media were assessed for the presence of bisphenols. PARTICIPANTS/MATERIALS, SETTING, METHODS: Ten different bisphenols (bisphenol A, S, AF, AP, B, C, E, F, P and Z) were measured using an isotopic dilution according to an on-line solid phase extraction/liquid chromatography/mass spectrometry method. MAIN RESULTS AND THE ROLE OF CHANCE: While the plastic consumables did not release bisphenols under routine conditions, 16 of the 18 cell culture and ART media assessed contained BPS. Six media exhibited BPS concentrations higher than 1 nM and reached up to 6.7 nM (1693 ng/l). LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: Further studies are required to investigate a greater number of ART media to identify less potentially harmful ones, in terms of bisphenol content. WIDER IMPLICATIONS OF THE FINDINGS: As BPS has already been reported to impair oocyte quality at nanomolar concentrations, its presence in ART media, at a similar concentration range, could contribute to a decrease in the ART success rate. Thus far, there has been no regulation of these compounds in the ART context. STUDY FUNDING/COMPETING INTERESTS: This study was financially supported by the 'Centre-Val de Loire' Region (Bemol project, APR IR 2017), INRAE, BRGM, the French National Research Agency (project ANR-18-CE34-0011-01 MAMBO) and the BioMedicine Agency (Project 18AMP006 FertiPhenol). The authors declare that they have no conflict of interest that could be perceived as prejudicing the impartiality of the reported research.


Subject(s)
Benzhydryl Compounds , Endocrine Disruptors , Benzhydryl Compounds/toxicity , Cell Culture Techniques , Culture Media , Female , Humans , Phenols , Sulfones
2.
Ultrason Sonochem ; 40(Pt B): 183-192, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28359634

ABSTRACT

PMMA particle synthesis was performed from MMA (methyl methacrylate) and water mixtures, exposed to different ultrasonic systems and frequencies. The sonication sequence was 20kHz→580kHz→858kHz→1138kHz, and the solution was sampled after each irradiation step for polymerization. Effects of sonication parameters (time, power), polymerization method (thermo-initiated or photo-initiated), use of small amounts of surfactant (Triton X-100™ or Tween® 20) and initial MMA quantity were investigated on particle size and synthesis yields. Particle size and size distribution were measured by DLS (Dynamic Light Scattering), and confirmed via SEM (Scanning Electron Microscopy) images. Synthesis yield was calculated using the dry weight method. Particle composition was estimated using FTIR (Fourier Transform Infra-Red) spectroscopy. PMMA (polymethylmethacrylate) monodispersed particles were successfully synthesized, with a possibility of control in the 78-310nm size range. These sized-controlled particles were synthesized with a 7.5-85% synthesis yield (corresponding to 7.5-40g/L particle solid content), depending on operational parameters. Furthermore, a trade-off between particle size and synthesis yield can be proposed: 20kHz→10min waiting time→580kHz→858kHz leading to 90nm particles diameter with 72% yield in less than 40min for the whole sequence. Thus, the synthesis under ultrasound can be found easy to implement and time efficient, ensuring the success of the scale-up approach and opening up industrial applications for this type of polymeric particles.

3.
Langmuir ; 32(1): 102-11, 2016 Jan 12.
Article in English | MEDLINE | ID: mdl-26632761

ABSTRACT

Optimization of surface treatment for reversible adhesion of micro-objects in liquid environment for the need in microassembly processes is presented. A spherical borosilicate probe and planar oxidized silicon wafer substrates were modified by deposition of pH sensitive polyelectrolyte films through layer-by-layer technique. Branched polyethylenimine (b-PEI) and poly(sodium styrenesulfonate) (PSS) were deposited in alternating manner on surfaces, and the influence of polyelectrolyte concentration, pH of deposition, and number of layers on the adhesion were successively examined. The multilayer buildup was followed by optical reflectometry (OR) and dissipative quartz crystal microbalance (QCM-D). The adhesion forces were monitored in aqueous environment at variable pH values by colloidal probe AFM microscopy. The thermodynamic work of adhesion was derived from the pull-off forces by using the Johnson-Kendall-Roberts (JKR) model and compared to the work of adhesion determined from contact angle measurements. It was found out that they correlate well, however, the values accessed from JKR model were underestimated, which was attributed mainly to the effect of surface roughness. Obtained results have demonstrated that it is possible to achieve repeatable reversible adhesion with the change of pH of submerged environment by appropriately tailoring the surface properties and therefore the prevailing surface forces.

4.
Prog Urol ; 25(5): 233-9, 2015 Apr.
Article in French | MEDLINE | ID: mdl-25640027

ABSTRACT

Primary endpoint was to objective a better effectiveness of flexible ureteroscopy (fURS) compared to extracorporeal shock wave lithotripsy (ESWL) 3 months after treatment of a unique kidney stone from 5 to 20mm. Secondary endpoints were to evaluate effectiveness in subgroup and tolerance. We conducted a prospective comparative randomised trial between May 2012 and February 2014. A computerised tomography was done before treatment and another 3 months after treatment. Of the 30 randomised patients, 8 dropped out from the study and 4 were lost to follow-up. Median time of follow-up was 3.82 months. In per-protocol analysis, success rate was 60% for fURS group versus 28.6% for ESWL group (P=0.29). In intention to treat analysis, success rate was 77.8% in fURS group versus 53.8% in ESWL group (P=0.38). In ESWL group, 5 patients (41.7%) needed a second treatment versus none in fURS group but it was not significant. During follow-up, 1 patient in each group presented a complication. Results of this feasibility study did not allowed to conclude on superiority of a technic. A multicenter study with more important enrollment is necessary considering economic side and tolerance of these treatments.


Subject(s)
Kidney Calculi/therapy , Lithotripsy , Ureteroscopy , Female , Follow-Up Studies , Humans , Kidney Calculi/diagnostic imaging , Kidney Calculi/surgery , Lithotripsy/methods , Male , Middle Aged , Prospective Studies , Reoperation , Tomography, X-Ray Computed , Treatment Outcome , Ureteroscopy/instrumentation , Ureteroscopy/methods
5.
Ultrason Sonochem ; 22: 220-6, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24835022

ABSTRACT

This paper deals with the effect of ultrasound on polypyrrole/SiO2 composite film elaboration through various steps (particle dispersion, electrosynthesis). Experiments were carried out on stainless steel in phosphoric acid solution. An efficient method for dispersion of SiO2 particles prior to electropolymerization, based on low frequency irradiation (20kHz), was proposed. It was shown that mechanical effects of high frequency ultrasound (i.e. mass transfer improvement) led to enhancement of electropolymerization kinetics. Scanning electron microscopy imaging and glow discharge optical emission spectroscopy revealed localization of SiO2 particles in the outer region of the films as well as better incorporation of particles under high frequency ultrasound irradiation. Finally, anticorrosion behavior of formed films was investigated in sodium chloride solution by Open Circuit Potential and anodic polarization methods. The results showed that polypyrrole/SiO2 films elaborated under ultrasound irradiation exhibit the best protective performances.

6.
J Colloid Interface Sci ; 431: 64-70, 2014 Oct 01.
Article in English | MEDLINE | ID: mdl-24984072

ABSTRACT

Self-assembled multilayer films made of PEDOT:PSS poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) and PDDA poly(diallyldimethylammonium chloride) were prepared using layer-by-layer method. In order to modify the growth regime of the multilayer, to fabricate an electrical conductive film and to control its thickness, the effects of pH, type of electrolyte, ionic strength and polyelectrolyte concentration were investigated. Optical reflectometry measurements show that the pH of the solutions has no effect on the film growth while the adsorbed amount increases more rapidly when BaCl2 is used instead of NaCl as electrolyte. An increase in the ionic strength (with NaCl) induces a change in the growth regime from a linear to an exponential one at low polyelectrolyte concentration. As UV-vis measurements indicate, no decomplexation of PEDOT was recorded after film preparation. With polyelectrolyte concentration below 1 g L(-1), no conductive films were obtained even if 50 bilayers were deposited. A conductive film was prepared with a polyelectrolyte concentration of 1 g L(-1) and the measured conductivity was 0.3 S m(-1). A slight increase in conductivity was recorded when BaCl2 was used probably due to a modification of the film structure.

7.
J Colloid Interface Sci ; 378(1): 77-82, 2012 Jul 15.
Article in English | MEDLINE | ID: mdl-22560491

ABSTRACT

The 24 h stability of bare silicon wafers as such or silanized with CH(3)O-(CH(2)-CH(2)-O)(n)-C(3)H(6)-trichlorosilane (n=6-9) was investigated in water, NaCl, phosphate and carbonate solutions, and in phosphate buffered saline (PBS) at 37 °C (close to biological conditions regarding temperature, high ionic strength, and pH). The resulting surfaces were analyzed using ellipsometry, X-ray Reflectometry (XRR), X-ray Photoelectron Spectroscopy (XPS), and Atomic Force Microscopy (AFM). Incubation of the silanized wafers in phosphate solution and PBS provokes a detachment of the silane layer. This is due to a hydrolysis of Si-O bonds which is favored by the action of phosphate, also responsible for a corrosion of non-silanized wafers. The surface alteration (detachment of silane layer and corrosion of the non-silanized wafer) is also important with carbonate solution, due to a higher pH (8.3). The protection of the silicon oxide layer brought by silane against the action of the salts is noticeable for phosphate but not for carbonate.


Subject(s)
Bisphenol A-Glycidyl Methacrylate/chemistry , Phosphates/chemistry , Silicon/chemistry , Sodium Chloride/chemistry , Buffers , Humans , Hydrogen-Ion Concentration
8.
J Colloid Interface Sci ; 376(1): 202-8, 2012 Jun 15.
Article in English | MEDLINE | ID: mdl-22456274

ABSTRACT

The functionalization of an organic polyethersulfone membrane (PES) was performed by alternating deposition of poly(allylamine hydrochloride) (PAH) and poly(sodium 4-styrene sulfonate) (PSS), leading to the formation of a polyelectrolyte multilayer film (PEM). The resulting assembly was characterized by tangential streaming potential measurements to determine the charge of the modified membranes as a function of the polyelectrolyte solution concentration and as a function of the immersion time of the membrane in the polyelectrolyte solutions. Then, the modified membranes were used to perform the ultrafiltration of aqueous solutions containing copper(II) ions. Different operating conditions were tested including: polyelectrolyte concentration, polyelectrolyte nature, thickness of the PEM film or pH of the Cu(2+) solutions. These filtration experiments demonstrated that it was possible to obtain a satisfactory retention of the copper ions (88%), thus proving that this type of assembly can be useful for the removal of copper ions from contaminated aqueous solutions.

9.
J Colloid Interface Sci ; 324(1-2): 118-26, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18533173

ABSTRACT

Grafting silicon wafers with CH(3)O(CH(2)CH(2)O)(n)C(3)H(6)-trimethoxysilane and -trichlorosilane (n=6 to 9) was performed in different conditions (solvent, reaction time, washing) in order to select procedures compatible with the design of nanostructured surfaces for biomaterial applications, using electron-beam lithography. After a first screening by principal component analysis (PCA), the X-ray photoelectron spectroscopy (XPS) data were analyzed by plotting the carbon to oxygen molar ratio vs the molar ratio of carbon singly bound to oxygen [CO] over carbon bound only to carbon and hydrogen [C(C,H)]. This was found to be a convenient method for discarding samples containing free polymerized silane. Such excess occurred as a result of insufficient washing or unsuitable solvent for the reaction (ether), as confirmed by AFM and thickness measured by X-ray reflectometry. Angle resolved XPS analysis indicated that the grafted silane layer had a 1-2 nm thickness and was covered by a thin layer of adventitious contaminant. As a result, the surface chemical composition obtained covered a broad range (O/C of 0.4 to 1.1; CO/C(C,H) of 2.5 to 6.5); variations could not be related to the nature of the silane reagent and no significant difference was found between hexane and toluene as solvent for the reaction. The grafted silane layer was not stable upon incubation during 24 h in phosphate buffered saline (PBS) at 37 degrees C, which mimics biological environments. As a consequence, the grafted wafers did not show protein repellent properties. This alteration was not observed at room temperature. XPS analysis demonstrated that silane layer detachment was due to a hydrolysis within the SiO(2) layer initially present at the wafer surface.


Subject(s)
Coated Materials, Biocompatible/chemistry , Polyethylene Glycols/chemistry , Silicon/chemistry , Adsorption , Equipment Failure , Hydrolysis , Proteins , Silanes/chemistry
10.
Eur J Surg Oncol ; 34(4): 377-81, 2008 Apr.
Article in English | MEDLINE | ID: mdl-17604937

ABSTRACT

AIMS: To evaluate the surgical management of patients who underwent VLNB for breast microcalcifications. METHODS: This retrospective study compared the histological results and the surgical procedures in two groups of patients, group 1: large-core needle biopsy n=1009, and group 2: surgical biopsy n=270. RESULTS: After VLNB, 54% patients were not operated on after stereotactic large-core needle biopsy, 42% underwent one operation, 4% underwent two operations and 0.2% underwent three operations. No surgery was performed for 95% of benign lesions. Multiples operations were necessary in 12% of patients with malignant lesions of VLNB group compared to 45% in the surgical biopsy group. The rate of underdiagnosis of borderline lesions and ductal carcinomas in situ was 16% by the large-core biopsy technique. CONCLUSION: VLNB constitutes an alternative to surgical biopsy. This procedure avoids surgery for most benign lesions and reduces the number of surgical procedures in malignant lesions.


Subject(s)
Breast Diseases/pathology , Breast Diseases/surgery , Calcinosis/pathology , Calcinosis/surgery , Biopsy, Needle , Breast Neoplasms/pathology , Breast Neoplasms/surgery , Carcinoma, Intraductal, Noninfiltrating/pathology , Carcinoma, Intraductal, Noninfiltrating/surgery , Female , Humans , Retrospective Studies
11.
J Colloid Interface Sci ; 314(2): 358-66, 2007 Oct 15.
Article in English | MEDLINE | ID: mdl-17659298

ABSTRACT

The layer-by-layer deposition of two polyelectrolytes, quaternized poly(dimethylaminoethyl methacrylate chloride) (MADQUAT) and poly(acrylic acid) (PAA) on a silica substrate was investigated using optical reflectometry, as a function of pH (pH 4, 5.5 and 9), ionic strength (10(-3) to 10(-1) M) and type of salt. Attention was given to the successive deposited weights and to the corresponding deposited charge densities within the ten first deposited layers. Results show a change of growth regime between an early stage where the substrate had a dominating influence in the build-up and a second stage where the polymer uptake was ruled essentially by polymer-polymer interactions. The pH was seen to influence the growth via the charge densities of silica (first stage) and PAA (first and second stages). The increase of NaCl concentration induced an increase of the film weight between 10(-3) and 10(-2) M, but the trend was more sophisticated between 10(-2) and 10(-1) M where the polymer uptake increased in the first stage of the growth and decreased in subsequent layers. The film weight increased in accordance with the rank of ions in the Hofmeister series. AFM images revealed a heterogeneous film morphology with bumps and valleys, which was explained by a growth mechanism made of the successive formation and growth of polymer complexes.

12.
J Colloid Interface Sci ; 296(2): 409-18, 2006 Apr 15.
Article in English | MEDLINE | ID: mdl-16293259

ABSTRACT

This work aimed to the determination of weight uptakes and charge balance in the course of successive deposition of polyelectrolytes, using the so-called self-assembled multilayer technique. Polyelectrolytes were the quaternized polydimethylaminoethyl methacrylate chloride, (MADQUAT) and poly(acrylic acid) (PAA). Experiments were made at pH 5.5 in NaCl solutions between 10(-3) and 10(-1) M. Deposits (5 bilayers) on a gold substrate were monitored using a quartz crystal microbalance (QCM) and optical fixed-angle reflectometry. Analysis of data lead to the determination of the sensitivity factor of the reflectometric output. QCM allowed the direct measurement of weight uptakes in 10(-3) and 10(-2) M solutions, while the viscoelastic properties of the film did not look appropriate for the measurement in 10(-1) M solutions. The layer-by-layer uptakes and charge balances in 10(-3) and 10(-2) M solutions revealed a large contribution of the counterions in the neutralization of the electrical charge in the film, more so for the highly charged MADQUAT polymer. The difference between two successive polymer charge densities increased significantly with the layer number and the electrolyte concentration. The increase of NaCl concentration induced an increase of MADQUAT but reversely a decrease of PAA deposits. The results were consistent with the determining influence of the salt in polyelectrolyte adsorption, both with regards to the concentration and the type of ions that has been well demonstrated in the literature. This work also draws attention to the role of small ions in the structural and application properties of self-assembled multilayer films.

13.
Science ; 288(5467): 834-6, 2000 May 05.
Article in English | MEDLINE | ID: mdl-10796999

ABSTRACT

A (phosphanyl)(trifluoromethyl)carbene is shown to be stable for weeks in solution at temperatures up to -30 degrees C. Its chemical behavior exactly matches that of its transient congeners, even to the extent that subtle effects, such as the recently discovered weak pi interaction with aromatics, are observed. The influence of substituents on the structure of push-pull carbenes is demonstrated by a single-crystal x-ray diffraction study of a (phosphanyl)[2, 6-bis(trifluoromethyl)phenyl]carbene. The lifetime of these molecules makes them accessible to a wider range of standard techniques, allowing their chemical and physical behaviors to be studied in more detail than was previously possible.

14.
Qual Life Res ; 7(3): 245-56, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9584555

ABSTRACT

The McMaster Health Utilities Indexes Mark 2 (HUI2) and 3 (HUI3) are multiattribute health classification systems, for which multiattribute preference functions have been developed in Canada. They provide a comprehensive instrument for use in economic evaluations and population health survey studies. This paper reports on the first results on the adaptation of the HUI2 and HUI3 systems cross-culturally and the assessment of the validity and reliability of the French self-report questionnaire in different patient populations. The cross-cultural adaptation included translation, backtranslations, an expert consensus meeting and pre-test with a few patients and healthy subjects in order to produce a conceptually equivalent French version of the 15 question self-report questionnaire and the HUI2 and HUI3 classification systems. Different groups of patients attending specialized clinics (n = 709) completed the questionnaire and another generic questionnaire (the Sickness Impact Profile (SIP)) for validity assessment. Physicians and patients were also asked for a global subjective assessment of the patient's health status. The French questionnaire was well received by the patients. The criterion and convergent validities of both classification systems (correlations with the patients' and physicians' assessments and with the responses to the SIP questionnaire) were satisfactory. The internal consistency was acceptable too (Cronbach's alpha = 0.81), as was the 3 day test-retest reproducibility. These first results authorize careful use of the 15 question self-report questionnaire in French. An assessment of the multiattribute preference function for the HUI3 system in France will be the study's next objective.


Subject(s)
Cultural Characteristics , Health Status Indicators , Quality-Adjusted Life Years , Surveys and Questionnaires/standards , Translating , Adolescent , Adult , Aged , Aged, 80 and over , Canada , Female , France , Humans , Linguistics , Male , Middle Aged , Psychometrics , Reproducibility of Results
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