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1.
Langmuir ; 33(40): 10736-10744, 2017 10 10.
Article in English | MEDLINE | ID: mdl-28922924

ABSTRACT

Plasma polymer films that contain amine groups (NH2-PPFs) are known to degrade over time, particularly in aqueous environments. To reduce such aging effects, a vertical chemical gradient regarding the amine group density was explored ranging over a few nanometers at the coating surface. The gradient-containing nanofilms were formed in low-pressure plasma by tuning plasma conditions while keeping the plasma "switched on". The coating process started with a more cross-linked NH2-PPF (70 W, 4:7 NH3/C2H4), followed by the deposition of a few nanometers of a less cross-linked yet more functional NH2-PPF (50 W, 7:7 NH3/C2H4). Characterization of the prepared gradient coatings showed that the chemical composition depends on the NH3/C2H4 gas flow ratio, as observed by different analytical methods: plasma diagnostics during deposition and depth profiling analyses of the deposited coating. Finally, surface chemistry was analyzed during air and water aging, showing a similar aging process of the NH2-PPF single layer and NH2-PPF with a vertical chemical gradient in air, while the stability of the gradient coating was found to be enhanced under aqueous conditions maintaining an [NH2]/[C] amount of ∼1%.

2.
J Environ Manage ; 143: 99-105, 2014 Oct 01.
Article in English | MEDLINE | ID: mdl-24905639

ABSTRACT

The development of a new material designed to trap heavy metals from sediments or wastewater, based on a polypropylene non-woven covalently grafted with cysteine, has been reported in a previous paper (Part A). The non-woven was first functionalized with acrylic acid (AA) which is used as spacer, and then cysteine was immobilized on the substrate through covalent coupling in order to obtain the so-called PP-g-AA-cysteine. Some preliminary heavy metals adsorption tests gave interesting results: at 20 °C for 24 h and in a 1000 mg/L heavy metals solution, PP-g-AA-cysteine adsorbs 95 mg Cu/g PP (CuSO4 solution), 104 mg Cu/g PP (Cu(NO3)2 solution), 135 mg Pb/g PP (Pb(NO3)2 solution) and 21 mg Cr/g PP (Cr(NO3)3 solution). In this second part of the work, heavy metals sorption tests were carried out with Cu (II), Pb (II), and Cr (III) separately, in order to determine the sorption capacity of this new sorbent as a function of (i) the heavy metals concentration in the solution, (ii) the contact time with the solution, (iii) the pH and (iv) the ionic strength of the solution containing heavy metals. Moreover, the sorption capacity of PP-g-AA-Cysteine was studied using a polluted solution consisting of a mixture of these different heavy metals. An Electron Paramagnetic Resonance study was finally carried out in order to determine the coordination geometry in the environment of the copper trapped by the PP-g-AA-cysteine.


Subject(s)
Metals, Heavy/isolation & purification , Water Pollutants, Chemical/isolation & purification , Acrylates/chemistry , Adsorption , Chromium/chemistry , Chromium/isolation & purification , Copper/chemistry , Copper/isolation & purification , Cysteine/chemistry , Electron Spin Resonance Spectroscopy , Hydrogen-Ion Concentration , Kinetics , Lead/chemistry , Lead/isolation & purification , Metals, Heavy/chemistry , Osmolar Concentration , Sodium , Solutions/chemistry , Water Pollutants, Chemical/chemistry
3.
J Environ Manage ; 132: 107-12, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24291583

ABSTRACT

Cysteine is an interesting biomolecule in the heavy metals trapping field, thanks to its amino, thiol and carboxylic groups. This amino acid is indeed present in some natural chelating agents: glutathione, phytochelatins and metallothioneins. However, cysteine has never been used in remediation processes. When immobilized on a polypropylene nonwoven (PP) geotextile, an innovative and eco-friendly material is obtained, with potential use in drainage and filtration of wastewaters and sediments. PP was first functionalized with acrylic acid using a low pressure cold plasma process to bring reactive carboxylic functions onto the surface (PP-g-AA). Cysteine was then covalently grafted on this modified PP. The cysteine grafting on PP-g-AA was optimized using response surface methodology, which allowed concluding that the best conditions of immersion without heating consist in: a solution containing 0.229 mol/L of cysteine for 28 h. The materials were characterized by Scanning Electron Microscopy, InfraRed Spectroscopy and X-ray Photoelectron Spectroscopy: evidence of covalent cysteine grafting was given. Preliminary sorption tests at 20 °C and pH = 4.5 with artificially polluted solutions give promising results for divalent heavy metal ions: 95 mg Cu (II) (CuSO4 solution), 104 mg Cu (II) and 135 mg Pb(II) (with NO3(-) counter-ion) per gram of PP are trapped.


Subject(s)
Copper/chemistry , Cysteine/chemistry , Lead/chemistry , Polypropylenes/chemistry , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/chemistry , Adsorption , Microscopy, Electron, Scanning , Photoelectron Spectroscopy , Spectrophotometry, Infrared , Waste Disposal, Fluid/instrumentation
4.
Clin Rheumatol ; 19(4): 291-5, 2000.
Article in English | MEDLINE | ID: mdl-10941811

ABSTRACT

Anti-SSA/Ro antibodies are the most prevalent type of antinuclear antibody (ANA). Anti-SSA/ Ro-positive sera may recognise two proteins: a 52 kDa (Ro52) and a 60 kDa (Ro60) subunit. We studied the sensitivity for Ro60 detection using the HEp-2000 substrate, which consists of HEp-2 cells transfected with Ro60 cDNA in an anti-SSA/Ro-positive population consecutively identified by double immunodiffusion (DID) with thymus/spleen nuclear extract and line immunoassay (LIA) with recombinant Ro52 and Ro60. One hundred and twenty-seven consecutive anti-SSA/Ro-positive sera defined by DID with thymus/spleen nuclear extract and LIA using recombinant Ro52 and Ro60 were analysed on HEp-2000 and DID with natural Ro60. Of these, 91 were anti-Ro60 positive on LIA and/ or DID with natural Ro60. The HEp-2000 substrate detected 70/91 (sensitivity 77%) and correlated strongest with DID. Most of the missed anti-Ro60-positive sera had high ANA intensity. The substrate did not detect monospecific anti-Ro52 antibodies (sensitivity 9.7%; 3/31). HEp-2000 substrate can therefore be considered a reliable, simple and alternative method for DID in the detection of anti-Ro60 reactivity. Special follow-up should be given to sera with strong ANA patterns in which the SSA/Ro60 staining pattern may be hidden.


Subject(s)
Antibodies, Antinuclear/blood , Autoantigens/immunology , Nuclear Proteins/immunology , Ribonucleoproteins/immunology , Adult , Antigens, Nuclear , DNA-Binding Proteins/immunology , Female , Fluorescent Antibody Technique, Indirect , Humans , Immunoassay , Immunodiffusion , Infant, Newborn , Lupus Erythematosus, Systemic/immunology , Male , Sensitivity and Specificity , Staining and Labeling , Transfection , Tumor Cells, Cultured
5.
Clin Exp Rheumatol ; 11(4): 393-7, 1993.
Article in English | MEDLINE | ID: mdl-8403584

ABSTRACT

The occurrence of antinuclear antibodies (ANA) in the serum of 485 healthy volunteer blood donors was assessed. Sixty two sera displayed nuclear immunofluorescence staining on Hep-2 cells using a polyvalent anti-Ig conjugate. In general, the titer of these antibodies was low (42/62 sera displaying a titer lower than or equal to 1:80). In only 23 sera were the ANA of the IgG isotype, which is the more disease-related immunoglobulin class of autoantibodies. In order to define the frequency of antibodies to extractable nuclear antigens and dsDNA within this population, sera were further analyzed by counterimmunoelectrophoresis. Western blot and the Crithidia luciliae assay. One serum displayed weak antids DNA reactivity; another serum had anti-SSA/Ro activity. On Western blot several patterns were found. They could not be identified with any of the available reference antisera.


Subject(s)
Antibodies, Antinuclear/blood , Blood Donors , Adolescent , Adult , Aged , Antibody Affinity , Blotting, Western , Counterimmunoelectrophoresis , Female , Fluorescent Antibody Technique , Humans , Immunity, Innate , Male , Middle Aged
6.
Eur Urol ; 23(3): 386-93, 1993.
Article in English | MEDLINE | ID: mdl-8508895

ABSTRACT

Endoscopic correction of vesicoureteric reflux in children has been performed in several hundred cases with the use of Teflon or cross-linked bovine collagen. The main criticism to this simple procedure is the potential migration of Teflon particles and the local pathological reaction. An experimental study was performed in 20 rabbits injected with Teflon or collagen in the bladder submucosa. A pathological examination of the bladder, lymph nodes, liver, lungs and brain was performed several months after the experiment to study the migration and the local reaction. There is no local granulomatous reaction with collagen while a local granulomatous reaction is found in the site of injection of Teflon and in 1 locoregional lymph node. The colonization of collagen by histiocytes increases with time. No distant granulomatous reaction was noted with both injections on histological examination. A mineralogic technique was applied after homogenisation of the lungs and brain to further investigate the distant migration problem. Rare particles of Teflon were observed in the lungs but not in the brain. The pathological significance of these particles remains unclear, but calls for research for different injection materials.


Subject(s)
Collagen/therapeutic use , Polytetrafluoroethylene/therapeutic use , Vesico-Ureteral Reflux/therapy , Animals , Brain/pathology , Brain Chemistry , Collagen/adverse effects , Collagen/analysis , Endoscopy , Foreign-Body Migration , Granuloma/pathology , Immunohistochemistry , Liver/chemistry , Liver/pathology , Lung/chemistry , Lung/pathology , Lymph Nodes/chemistry , Lymph Nodes/pathology , Polytetrafluoroethylene/adverse effects , Polytetrafluoroethylene/analysis , Rabbits , Urinary Bladder/chemistry , Urinary Bladder/pathology
7.
J Urol (Paris) ; 99(6): 344-8, 1993.
Article in French | MEDLINE | ID: mdl-7516386

ABSTRACT

Over 2 years, 191 patients with symptomatic benign prostatic hypertrophy (BPH) have been treated by transurethral radiofrequency heating of the prostate at various temperatures (44.5 and 47-48 degrees C) in one session. At 44.5 degrees C, 60% of the patients were subjectively improved and 71% at 47-48 degrees C. 58% of the patients in retention were catheter free after treatment. The mean increase in the peak flow was not significant no matter the temperature used. A subjective improvement is obviously demonstrated by the significant decrease in the overall symptom score and essentially by the reduction in the irritative symptoms such as nocturia and urgency. This new alternative approach may play a meaningful role in the symptomatic management of selected patients with BPH.


Subject(s)
Hyperthermia, Induced/methods , Prostatic Hyperplasia/therapy , Temperature , Humans , Male , Urinary Catheterization , Urodynamics
8.
Eur Urol ; 23(2): 302-6, 1993.
Article in English | MEDLINE | ID: mdl-7683991

ABSTRACT

In 2 years, 191 patients with symptomatic benign prostatic hypertrophy (BPH) were treated by transurethral radiofrequency heating of the prostate at various temperatures (44.5 and 47-48 degrees C) in one session. At 44.5 degrees C, 60% of the patients were subjectively improved and 71% at 47-48 degrees C. 58% of the patients in retention were catheter free after treatment. The mean increase in the peak flow was not significant in spite of the temperature used. A subjective improvement is obviously demonstrated by the significant decrease in the overall symptom score and essentially by the reduction in the irritative symptoms such as nocturia and urgency. This new alternative approach may play a meaningful role in the symptomatic management of selected patients with BPH.


Subject(s)
Hyperthermia, Induced , Prostatic Hyperplasia/therapy , Radio Waves , Follow-Up Studies , Humans , Hyperthermia, Induced/instrumentation , Male , Prostate-Specific Antigen/analysis , Temperature , Urinary Retention/therapy
9.
Eur Urol ; 22(1): 83-5, 1992.
Article in English | MEDLINE | ID: mdl-1330573

ABSTRACT

One case of penile verrucous carcinoma (Buschke-Löwenstein tumor) undergoing anaplastic transformation and containing human papillomavirus type 6 is presented. The viral genome is detected by in situ hybridization using biotin-labeled cDNA probes. The clinical, histological and virologic criteria of verrucous carcinoma are discussed in comparison to giant condyloma and highly differentiated squamous cell carcinoma. The importance of viral typing determination for further diagnostic and therapeutic procedures is emphasized.


Subject(s)
Carcinoma, Papillary/diagnosis , Carcinoma, Papillary/microbiology , Papillomaviridae/classification , Penile Neoplasms/diagnosis , Penile Neoplasms/microbiology , Aged , Carcinoma, Papillary/pathology , DNA Probes, HPV , Humans , In Situ Hybridization , Male , Penile Neoplasms/pathology
10.
Clin Chem ; 36(2): 337-9, 1990 Feb.
Article in English | MEDLINE | ID: mdl-2105861

ABSTRACT

A fast immunoblotting procedure, termed "microgel diffusion blotting," is used to detect and identify antibodies to extractable nuclear antigens (i.e., to Sm, RNP, and SSB) in patients with rheumatic diseases. The method differs from the standard immunoblotting techniques by the use of ultra-thin microgels for polyacrylamide gel electrophoresis: the very thin gel layer allows transfer of proteins to a nitrocellulose membrane by simple diffusion. Principal advantages of this variant technique are its simplicity, rapidity, and reproducibility--characteristics that make the test suitable for routine application. We compared the sensitivity of the test with that of double immunodiffusion in agarose for the evaluation of humoral antinuclear immunity. Microgel diffusion blotting detected antibodies in serum at concentrations less than 0.001 of those detectable by immunodiffusion.


Subject(s)
Autoantibodies/analysis , Nuclear Proteins/immunology , Ribonucleoproteins/immunology , Antigens, Nuclear , Electrophoresis, Polyacrylamide Gel/methods , Humans , Immunoblotting/methods , Immunodiffusion , Rheumatic Diseases/immunology
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