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1.
Photochem Photobiol Sci ; 21(9): 1617-1626, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35678956

ABSTRACT

The decomposition of ethanol, one of the most important biomass platform molecules, was investigated under green conditions, ambient temperature, atmospheric pressure and air for the synthesis of acetal in the presence of TiO2 activated under UV-A radiation. The impact of ethanol concentration, of the nature of TiO2 (rutile, anatase or mixture), of the photo-deposition of Pt under air or argon were all factors under investigation. Whatever the conditions and the nature of catalyst used, acetaldehyde was initially formed before reacting with ethanol to form acetal, a promising fuel additive. However, the subsequent generation of acetal differs depending on the conditions and the nature of catalyst. In the absence of a noble metal, rutile TiO2 leads to an increase in acetal formation at equivalent acetaldehyde formation. This behavior is discussed considering the acidic and basic properties of rutile and anatase phases together with H+ generated under UV. In the presence of Pt, under air or Ar, the acetal formation begins at a lower concentration of acetaldehyde due to the in-situ photo-deposition of Pt. However, whereas acetal formation is similar for Pt/anatase and Pt/rutile phase under air, under Ar, less acetal is generated on Pt/rutile in agreement with the production of more H2.


Subject(s)
Acetals , Ethanol , Acetaldehyde , Titanium/chemistry
2.
Chemosphere ; 297: 133940, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35231472

ABSTRACT

Herein, we investigate the interplay between a photocatalyst (TiO2) and a catalyst (Pt/TiO2 and Pt/CeO2) for the oxidation of formaldehyde and toluene at room temperature. A luminous textile is used as support and as light source for the photocatalyst. Our results indicate that the presence of the catalyst and the photocatalyst increases the catalytic performance for the oxidation of formaldehyde, while the photocatalytic performance for toluene oxidation decreases. The overall performance (toluene and formaldehyde degradation) of the system can be optimized with respect to the choice of support for the catalyst (e.g. TiO2 or CeO2), the quantity of Pt used, and the ratio between the catalyst and photocatalyst. In addition, different configurations of the photocatalyst and the catalyst on the textile are studied: under leaching and flow-through gas streams, catalyst and photocatalyst deposition on the same and opposite site of the textile are tested. The performance of the system can be optimized by adapting a configuration where the gas stream goes through the textile, while the deposition side of the catalyst and/or photocatalyst with respect to the gas stream is of minor importance.

3.
Encephale ; 41(3): 202-8, 2015 Jun.
Article in French | MEDLINE | ID: mdl-24793794

ABSTRACT

AIM OF THE STUDY: The experiment studied the effects of a short duration exposure to traumatic memories using magneto-encephalography (MEG). PATIENTS: Nine right-handed DSM-4 PTSD patients were recruited from a unit for anxiety disorders and an organisation supporting victims of violence. In order to have a homogeneous sample, we included only women who suffered from civilian PTSD. Exclusion criteria were co-morbid major medical illness, metallic dental prostheses that would interfere in the magnetic measurement, and current drug treatment. All participants were free from neurological disease and had normal hearing. They signed a written informed consent form. An ethics committee accepted the study. METHOD: A tape-recorded voice administered a script-driven imagery. The patients had to imagine, successively, a neutral image, a traumatic memory and rest, while MEG measured brain activities across delta, theta, alpha and beta bands. Each condition lasted three minutes. Heart rate (HR), anxiety and the vividness of mental images were recorded at the end of each phase. MEG power analysis was carried out with Statistical Parametric Mapping (SPM) 8. The signals were averaged for each of the three conditions of threeminutes duration. The dependent variable was a subtracted value: (trauma - rest) - (neutral - rest). The significance threshold was set at P<0.01. RESULTS: Anxiety and HR significantly increased during the trauma condition and returned to the neutral level during rest. The vividness of the mental imagery remained stable across the three conditions. The left-brain demonstrated a statistically significant power decrease in the secondary visual cortex (BA 18-19) in the delta band, the insula (BA13) in the beta band, the insula (BA13), premotor cortex (BA 6), Broca area (BA 44), and BA 43, in the alpha band. DISCUSSION: The symptom provocation protocol was successful in eliciting subjective anxiety and HR response in relation to traumatic memories. Our MEG results are in keeping with previous neuro-imagery studies showing decreased activities in the insula and Broca area during PTSD symptom provocation. However, we did not replicate the activation in the amygdala and the cingulate and prefrontal cortex found in some studies. Moreover, the within-group design, the small sample, and the inclusion of only female patients with milder dissociative symptoms limit our conclusions. The MEG protocol we used may also explain some partial discrepancies with previous MEG studies. However, our aim was to provoke a specific autobiographic recall of a traumatic event unfolding several sequential mental images along three minutes as in exposure therapy for PTSD. CONCLUSION: Despite its limitations, this pilot study is the first to provide MEG data during trauma recall. It suggests that recalling a specific traumatic event along three minutes results in hypo-activations of the brain regions regulating language and emotions. This paves the way to recording whole sessions of specific therapies for PTSD, with MEG using the millisecond resolution. MEG might be of interest to study the suppression of traumatic memories and their activation and habituation through prolonged graduated exposure in imagination across several sessions. MEG could also be used to study the effects of medication on PTSD symptoms. A controlled replication in a larger sample including male and female patients with various traumatic experiences is needed.


Subject(s)
Magnetoencephalography , Mental Recall/physiology , Stress Disorders, Post-Traumatic/physiopathology , Aged , Aged, 80 and over , Anxiety/diagnosis , Anxiety/physiopathology , Anxiety/psychology , Arousal/physiology , Brain Mapping , Brain Waves/physiology , Cerebral Cortex/physiopathology , Dominance, Cerebral/physiology , Female , Humans , Imagination/physiology , Infant , Life Change Events , Middle Aged , Pilot Projects , Stress Disorders, Post-Traumatic/diagnosis , Stress Disorders, Post-Traumatic/psychology , Violence/psychology
4.
Water Res ; 46(10): 3208-18, 2012 Jun 15.
Article in English | MEDLINE | ID: mdl-22503496

ABSTRACT

In order to compare the disinfection potential of photocatalysis and photochemistry, the effects of these two processes on bacteria in water were investigated under exposure to UV-A and UV-C. The well-known bacterial model Escherichia coli (E. coli) was used as the experimental organism. Radiation exposure was produced with an HPK 125 W lamp and the standard TiO(2) Degussa P-25 was used as the photocatalyst. Firstly, the impact of photocatalysis and photochemistry on the cultivability of bacterial cells was investigated. UV-A radiation resulted in low deleterious effects on bacterial cultivability but generated colonies of size smaller than average. UV-C photocatalysis demonstrated a greater efficiency than UV-A photocatalysis in altering bacterial cultivability. From a cultivability point of view only, UV-C radiation appeared to be the most deleterious treatment. A rapid epifluorescence staining method using the LIVE/DEAD Bacterial Viability Kit was then used to assess the modifications in bacterial membrane permeability. UV-A radiation did not induce any alterations in bacterial permeability for 420 min of exposure whereas only a few minutes of exposure to UV-C radiation, with the same total radiance intensity, induced total loss of permeability. Moreover, after 20 and 60 min of exposure to UV-C and UV-A photocatalysis respectively, all bacteria lost their membrane integrity, suggesting that the bacterial envelope is the primary target of reactive oxygen species (ROS) generated at the surface of TiO(2) photocatalyst. These results were further confirmed by the formation of malondialdehyde (MDA) during the photocatalytic inactivation of bacterial cells and suggest that destruction of the cell envelope is a key step in the bactericidal action of photocatalysis. The oxidation of bacterial membrane lipids was also correlated with the monitoring of carboxylic acids, which can be considered as representatives of lipid peroxidation by-products. Finally, damages to bacterial morphology induced by UV-C photocatalysis and photochemistry were investigated through Scanning electron microscopy (SEM). Bacterial cells were observed on microscopy pictures at exposure durations corresponding to a loss of cultivability. After 90 min of exposure to UV-C radiation, bacterial cells showed little alteration of their outer membrane whereas they suffered deep deleterious damages under UV-C photocatalysis exposure.


Subject(s)
Anti-Bacterial Agents/metabolism , Escherichia coli K12/radiation effects , Microbial Sensitivity Tests/methods , Photochemistry/methods , Ultraviolet Rays , Carboxylic Acids/chemistry , Catalysis/radiation effects , Cell Membrane/metabolism , Cell Membrane/radiation effects , Colony Count, Microbial , Escherichia coli K12/cytology , Escherichia coli K12/growth & development , Escherichia coli K12/ultrastructure , Kinetics , Lipid Peroxidation/radiation effects , Malondialdehyde/metabolism , Microscopy, Fluorescence , Phenotype
5.
Orthop Traumatol Surg Res ; 98(3): 363-5, 2012 May.
Article in English | MEDLINE | ID: mdl-22445465

ABSTRACT

In Tape Locking Screw (TLS(®)) ligamentoplasty, transplant bone fixation uses polyethylene terephthalate (PET). We report two cases of aseptic arthritis following anterior cruciate ligament (ACL) reconstruction using this material. Diagnosis was founded on negative sampling and complete cure following arthroscopic lavage and synovectomy without curative antibiotherapy. This complication was also described with other synthetic materials used in this indication (Dacron, PFTE, carbon), and with PET as transplant material but never as bone fixation material. The physiopathological hypothesis is in terms of PET particle release in the suprapatellar bursa; sinking the strips into the bone as fully as possible on implantation could avoid impingement. Longer TLS(®) ligamentoplasty series with adequate follow-up will be needed in order to estimate the true incidence of this complication.


Subject(s)
Anterior Cruciate Ligament Reconstruction/adverse effects , Anterior Cruciate Ligament/surgery , Arthritis/etiology , Bone Screws , Knee Injuries/surgery , Adult , Anterior Cruciate Ligament Injuries , Anterior Cruciate Ligament Reconstruction/methods , Arthritis/diagnosis , Arthroscopy , Follow-Up Studies , Humans , Knee Injuries/diagnosis , Male , Postoperative Complications , Prosthesis Design
6.
J Physiol Biochem ; 66(1): 39-46, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20405270

ABSTRACT

Human leukocyte antigen (HLA)-G is an immunomodulatory molecule discovered for the first time in the maternal-fetal interface. In cancer context, where high number of natural killer (NK) cells is described, the presence of HLA-G in its soluble form is thought to be essential for NK cells signaling. To evaluate intracellular signaling in NK cells upon HLA-G soluble forms stimulation, we investigate the role of soluble HLA-G (HLA-G5- and HLA-G1 shedding form) stimulation on classical nuclear factor (NF)-kappaB pathway activation. We reported that these two forms of soluble HLA-G could activate NF-kappaB in NK cells. NF-kappaB activation in NK cells does implicate neither phosphatidylinositol 3-kinase (PI3K) nor MEK (MAP kinase kinase) as demonstrated after specific inhibition experiments. We demonstrated elsewhere that NF-kappaB activation in NK cells is not implicated in cytotoxicity inhibition by HLA-G. Our findings may suggest the important role played by NF-kappaB activation after soluble HLA-G stimulation in other NK cells function.


Subject(s)
HLA Antigens/metabolism , Histocompatibility Antigens Class I/metabolism , Killer Cells, Natural/metabolism , NF-kappa B/metabolism , Cell Line, Tumor , HLA-G Antigens , Humans , Mitogen-Activated Protein Kinase Kinases/metabolism , Phosphatidylinositol 3-Kinase/metabolism , Signal Transduction , Transfection
7.
J. physiol. biochem ; 66(1): 39-46, mar. 2010.
Article in English | IBECS | ID: ibc-122848

ABSTRACT

No disponible


Human leukocyte antigen (HLA)-G is an immunomodulatory molecule discovered for the first time in the maternal–fetal interface. In cancer context, where high number of natural killer (NK) cells is described, the presence of HLA-G in its soluble form is thought to be essential for NK cellssignaling. To evaluate intracellular signaling in NK cells upon HLA-G soluble forms stimulation, we investigate the role of soluble HLA-G (HLA-G5- and HLA-G1 shedding form) stimulation on classical nuclear factor (NF)–κB pathway activation. We reported that these two forms of soluble HLA-G could activate NF–κB in NK cells. NF–κB activation in NK cells does implicate neither phosphatidylinositol 3-kinase (PI3K) nor MEK (MAP kinase kinase) as demonstrated after specific inhibition experiments. We demonstrated elsewhere that NF–κB activation in NK cells is not implicated in cytotoxicity inhibition by HLA-G. Our findings may suggest the important role played by NF–κB activation after soluble HLA-G stimulation in other NK cells function (AU)


Subject(s)
Humans , Killer Cells, Natural/physiology , HLA-G Antigens/physiology , NF-kappa B/physiology , Immunologic Factors/pharmacokinetics , Phosphatidylinositol 3-Kinase/physiology , Mitogen-Activated Protein Kinase Kinases/physiology
8.
Environ Technol ; 31(13): 1417-22, 2010 Dec 01.
Article in English | MEDLINE | ID: mdl-21214000

ABSTRACT

Amino acids are at the origin of the formation of odourous compounds after chlorination treatment. Our objectives were to test the efficiency of a photocatalytic process to remove these types of compounds. Five amino acids (AA)-phenylalanine, tyrosine, tryptophan, glycine and alanine--have been chosen as model molecules. The photocatalytic degradation has been investigated in aqueous solutions containing TiO2 suspensions as photocatalysts, in order to assess the adsorption, the disappearance rate and the mechanism of degradation. Results showed that only a small amount of amino acid is adsorbed corresponding to less than 1% of OH covered for aromatic amino acids and about 10% for linear amino acids. A comparison of disappearance rate, total organic carbon (TOC) removal and intermediate for these five amino acids are presented and discussed, taking into account their nature.


Subject(s)
Amino Acids/chemistry , Photochemistry , Catalysis , Chromatography, High Pressure Liquid , Tandem Mass Spectrometry , Titanium/chemistry
9.
Photochem Photobiol Sci ; 8(7): 1040-6, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19582281

ABSTRACT

Two commercial types of self-cleaning glass (SCG) have been tested to confirm the real photocatalytic nature of their properties. This was done by using four photocatalytic tests: (i) in the gas phase with the total oxidation of acetylene; (ii) in water with the total degradation of malic acid, (iii) in water with the total degradation of methylene blue, and (iv) in the solid phase with the total oxidative degradation of a layer of stearic acid deposited on the self-cleaning glass surface, in contact with the superficial titania coating. The influence of various factors (temperature, humidity, wavelength, radiant flux, presence of inorganic particles stuck at the glass surface) was explained in line with the fundamentals of photocatalysis. The results helped to understand the behaviour of self-cleaning glass.

10.
J Hazard Mater ; 166(2-3): 1195-200, 2009 Jul 30.
Article in English | MEDLINE | ID: mdl-19150749

ABSTRACT

The removal of biological or pharmaceutical compounds through the wastewater treatment becomes relevant. These compounds are present as traces in sewage. In this work, we propose a coupling process which combines the pre-concentration of the pollutant by selective extraction and then degradation of these pollutants by photocatalysis in presence of TiO2. This process is efficient at room temperature by activation of a photocatalyst (TiO2) under UV light. Aromatic amino acids were chosen as model of pharmaceutical pollutants. Their extraction from water, ensured by calixarene derivatives, and their photocatalytic degradation were investigated. It was shown that photodegradation follows a first-order kinetic and that the rate constant enhances with amino acid concentration. The effect of the pH on the rate constant will be discussed.


Subject(s)
Amino Acids, Aromatic/isolation & purification , Calixarenes/chemistry , Photolysis , Amino Acids, Aromatic/chemistry , Amino Acids, Aromatic/radiation effects , Catalysis , Hydrogen-Ion Concentration , Kinetics , Pharmaceutical Preparations/chemistry , Pharmaceutical Preparations/isolation & purification , Pharmaceutical Preparations/radiation effects , Solid Phase Extraction , Titanium , Ultraviolet Rays , Water Pollutants, Chemical
11.
Leukemia ; 22(3): 578-84, 2008 Mar.
Article in English | MEDLINE | ID: mdl-18059484

ABSTRACT

HLA-G5 is secreted by erythroblasts in all hematopoietic organs, suggesting a role for this protein in erythropoiesis. To examine this, we analyzed whether HLA-G5 affects the proliferation of UT7/EPO and HEL erythroleukemia cells and characterized the mechanism by which HLA-G5 influences erythropoietin receptor (EPOR) signaling. We show that HLA-G5 inhibits the proliferation of UT7/EPO cells, the EPOR signaling of which is similar to that of normal erythroid progenitors. HLA-G5-mediated inhibition was associated with reduced phosphorylation of JAK2 kinase and that of the downstream signaling proteins STAT-5 and STAT-3. Involvement of JAK2 in erythroid cell proliferation has been highlighted by the role of JAK2 V617F mutation in polycythemia vera (PV), a myeloproliferative disorder characterized by erythroid lineage overproduction. We demonstrate that HLA-G5 downregulates EPOR constitutive signaling of JAK2 V617F-expressing HEL cells, leading to inhibition of cell proliferation through G1 cell cycle arrest. Combination of HLA-G5 with JAK inhibitor I further decreases HEL cell growth. Clinical relevance is provided by analysis of PV patients who carry JAK2 V617F mutation, showing that HLA-G5 inhibits the formation of erythropoietin-independent erythroid colonies. Such HLA-G5-mediated inhibition constitutes a new parameter to be considered in the design of future approaches aimed at treating JAK2 V617F-positive myeloproliferative disorders.


Subject(s)
Erythropoiesis/physiology , HLA Antigens/physiology , Histocompatibility Antigens Class I/physiology , Polycythemia Vera/metabolism , Receptors, Erythropoietin/drug effects , Cell Division/drug effects , Cell Line, Tumor/drug effects , Cell Line, Tumor/metabolism , Colony-Forming Units Assay , Erythroid Precursor Cells/drug effects , Erythropoiesis/drug effects , Erythropoietin/physiology , G1 Phase/drug effects , HLA Antigens/blood , HLA Antigens/genetics , HLA Antigens/pharmacology , HLA-G Antigens , Histocompatibility Antigens Class I/blood , Histocompatibility Antigens Class I/genetics , Histocompatibility Antigens Class I/pharmacology , Humans , Janus Kinase 2/antagonists & inhibitors , Janus Kinase 2/genetics , Janus Kinase 2/metabolism , Leukemia, Erythroblastic, Acute/pathology , Microspheres , Mutation, Missense , Phosphorylation/drug effects , Point Mutation , Protein Processing, Post-Translational/drug effects , Receptors, Erythropoietin/physiology , Recombinant Fusion Proteins/pharmacology , STAT3 Transcription Factor/metabolism , STAT5 Transcription Factor/metabolism
12.
J Hazard Mater ; 146(3): 624-9, 2007 Jul 31.
Article in English | MEDLINE | ID: mdl-17532130

ABSTRACT

Photocatalysis is efficient in several fields. Firstly, in selective mild oxidation: oxidation of gas and liquid hydrocarbons (alkanes, alkenes, cyclo-alkanes, aromatics) into aldehydes and ketons. Primary and secondary alcohols are also oxidized into their corresponding aldehydes or ketones. The high selectivity was ascribed to a photoactive neutral, atomic oxygen species. Once platinized (only 0.5wt.% Pt) titania may catalyze reactions involving hydrogen (deuterium-alkane isotopic exchange and alcohol dehydrogenation). For fine chemicals, high initial selectivities enable titania to address most of the twelve principles of "green chemistry", such as the synthesis of 4-tert-butyl-benzaldehyde, an important intermediate in perfume industry by direct selective oxidation of 4-tert-butyl-toluene with air. A new field recently appeared: thio-photocatalysis. Oxygen was replaced by sulfur, using H(2)S as a convenient and reactive source. For instance, the conversion of propene in 1-propanthiol was successfully obtained. The reaction was performed using either CdS or TiO(2). The latter was much more active than CdS. In environmental photocatalysis, titania becomes a total oxidation catalyst once in presence of water because of the photogeneration of OH radicals by neutralization of OH(-) surface groups by positive holes. Many toxic inorganic ions are oxidized in their harmless upper oxidized state. The total degradation of organic pollutants (pesticides, herbicides, insecticides, fungicides, dyes, etc. ...) is the main field of water photocatalytic decontamination. The UVA solar spectrum can de advantageously used as demonstrated by many campaigns performed in the solar pilot plant at the "Plataforma Solar de Almeria" (Spain).


Subject(s)
Titanium/chemistry , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/radiation effects , Catalysis , Oxidation-Reduction , Photochemistry , Ultraviolet Rays
13.
Cell Mol Life Sci ; 63(22): 2669-81, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17072500

ABSTRACT

HLA-G is expressed by tumors, in which it contributes to the evasion of immunosurveillance. NF-kappaB appears to be a candidate for regulating HLA-G expression, since it is considered to be a hallmark of cancer. We investigated the role of NF-kappaB in modulating HLA-G expression in HLA-G-positive tumor cells, JEG-3 (choriocarcinoma), FON (melanoma), and M8-HLA-G1 (HLAG1-transfected melanoma). The treatment of tumor cells with two NF-kappaB inducers, tumor necrosis factor-alpha and phorbol 12-myristate 13-acetate, decreased HLA-G1 cell surface expression but increased intracytoplasmic HLA-G proteins. Reduction in HLA-G1 cell surface expression is driven by NF-kappaB and involves a proteolytic shedding process dependent on metalloproteinase activity. In contrast, an increase in intracytoplasmic HLA-G proteins involves post-transcriptional mechanisms that are independent of NF-kappaB. These results, and the fact that soluble HLA-G1 reduces the cytotoxicity of the NKL cell line, lead us to propose a novel regulatory pathway for HLA-G expression by tumor cells that may have particular relevance in tumor escape.


Subject(s)
Choriocarcinoma/immunology , HLA Antigens/metabolism , Histocompatibility Antigens Class I/metabolism , Melanoma/immunology , NF-kappa B/metabolism , Tetradecanoylphorbol Acetate/pharmacology , Tumor Necrosis Factor-alpha/pharmacology , Cell Line , Cell Line, Tumor , Cell Membrane/immunology , Choriocarcinoma/genetics , Choriocarcinoma/metabolism , Coculture Techniques , Cytotoxicity, Immunologic , Gene Expression Regulation, Neoplastic , HLA Antigens/genetics , HLA Antigens/immunology , HLA-G Antigens , Histocompatibility Antigens Class I/genetics , Histocompatibility Antigens Class I/immunology , Humans , Immunologic Surveillance , Killer Cells, Natural/immunology , Melanoma/genetics , Melanoma/metabolism , Protein Modification, Translational/drug effects , Protein Processing, Post-Translational/drug effects , Tumor Escape
14.
Encephale ; 31(1 Pt 1): 76-81, 2005.
Article in French | MEDLINE | ID: mdl-15971643

ABSTRACT

The post-traumatic stress disorder (PTSD) represents an original and frequent pathological entity concerning people confronted with one or more significant traumatic events. We present here a comparative study concerning subjects who present a post-traumatic stress disorder received in an anxiety disorder unit (ADU) or in a victims support association (VSA). One hundred and twenty seven people have been included in the study, according to DSMIV for PTSD, during three years. Fifty-seven came from a victim support association, 54 came from an anxiety disorder unit and 16 were common to both structures. The PCL-S (PTSD Checklist Scale) was used to rate the intensity of the PTSD. Age, sex, marital statute, type of traumatism, comorbidity and previous traumatisms were compared. PCLS scores were equivalent in the two settings. More women, younger subjects and more aggression were received in the victim support association. In the anxiety disorder unit more psychiatric comorbidity and more frequent antecedents of traumatism were seen. In the whole sample, two thirds of the people lived alone. Our results show that a victim support association receives people suffering from a definite post-traumatic stress disorder as intense on the PCL-S as in an anxiety disorder unit. More work has to be done on support association in the community, as they are confronted with significant PTSD problems.


Subject(s)
Anxiety Disorders/epidemiology , Crime Victims/psychology , Crime Victims/statistics & numerical data , Social Support , Stress Disorders, Post-Traumatic/epidemiology , Adolescent , Adult , Aged , Anxiety Disorders/diagnosis , Diagnostic and Statistical Manual of Mental Disorders , Female , Humans , Male , Middle Aged , Stress Disorders, Post-Traumatic/diagnosis , Surveys and Questionnaires
15.
Encephale ; 29(3 Pt 1): 232-8, 2003.
Article in French | MEDLINE | ID: mdl-12876547

ABSTRACT

Post-Traumatic Stress Disorder (PTSD) is a psychiatric disorder frequently found in psychiatric clinic and in the population of victims of traumatic events. PTSD, characterized by an intense fear, helplessness or horror, resulting from exposure to a traumatic event, is clinically manifested with three main syndromes: reexperiencing, avoidance behavior and numbing of emotion, and physiological hyperarousal. The Post-Traumatic Checklist Scale (PCLS) is a brief and self-report questionnaire for evaluating the severity of three main syndromes of PTSD. The scale can be divided into three sub-scores corresponding to the three main syndromes of the disorder: reexperiencing (items 1-5), avoidance (items 6-12) and hyperarousal (items 13-17). The validation studies in English version (Weathers et al., 1993, Blanchard et al., 1996) and French version (Ventureyra et al., 2001) showed that the PCLS possesses good psychometric properties. But the discriminating validation with another pathological group and the sensitivity of the scale to change of treatment have not yet been studied up to now. The aim of this study is the validation of the French version of the PCLS in Post-Traumatic Stress Disorder (PTSD) subjects compared with subjects suffering from other anxiety disorders and non-clinical subjects. The sensitivity of the PCLS after a cognitive behavioral therapy (CBT) for PTSD was studied for the first time. Fifty-seven outpatients suffering from PTSD according to DSM IV criteria, 23 patients suffering from other anxiety disorders and 28 non-clinical subjects were included in this study. All subjects were assessed with the PCLS. The Beck Depression Inventory--13 items (BDI-13) and the Fear Questionnaire (FQ) were used for the two groups of patients. Fifty-five PTSD patients were administered the PCLS twice over an interval of one to two weeks without any intervention in order to determine the test-retest reliability of the PCLS. And 24 PTSD patients were reassessed with the PCLS after 16 sessions of cognitive behavioral therapy (CBT) in order to study the sensitivity to treatment of the PCLS. The CBT technique for PTSD consisted of relaxation, exposition, recital, cognitive restructuration and stress management. The total score and the subscores on the PCLS were found to be significantly higher in PTSD patients than in two control groups: suffering from other anxiety disorders subjects (61.2/41.4, p<0.0001) and non-clinical subjects (61.2/28.8, p<0.0001). The correlation between the PCLS total score and the others measures showed that the PCLS correlated significantly with the depression measure, the BDI-13 (p<0.001), and the sub-scores of Fear Questionnaire (agoraphobia: p<0.001; anxiety-depression: p<0.001; distress: p<0.001), but not with the social phobia sub-score of the FQ. The PCLS showed a satisfactory test-retest reliability in 55 patients (the total score: r=0.75, p<0.0001; the sub-score of reexperiencing: r=0.844, p<0.0001; the sub-score of avoidance: r=0.702, p<0.0001; the sub-score of hyperarousal: r=0.712, p<0.0001). The t-test showed that the total score of the PCLS was significantly reduced in 24 patients after 16 sessions of CBT (the mean gain=13.1, t=5.63, p<0.0001). The results of our study confirm that the PCLS possesses good empirical and discriminating validity and a good sensitivity. The fact that the PTSD patients reported significantly higher total scores on the PCLS and its three subscores than other anxiety disorder subjects and non-clinical subjects indicates that the PCLS differentiates well the patients presenting PTSD from other anxiety disorder subjects and non-clinical subjects. The PCLS total score also correlates significantly with the other measures of psychopathology used in the study, such as measures of phobia (the Fear Questionnaire agoraphobia subscale), depression (the Beck Depression Inventory -13) and distress (the Fear Questionnaire distress subscale). This may be explained by the fact that some PTSD symptoms overlap with those of depression and of anxiety or phobia. The PCLS showed anxiety or phobia. The PCLS showed a satisfactory test-retest reliability. The PCLS is therefore a valid and effective measurement of PTSD. It may be a useful tool for screening and assessing PTSD in clinical practice and research in psychiatry.


Subject(s)
Stress Disorders, Post-Traumatic/diagnosis , Surveys and Questionnaires , Adult , Diagnostic and Statistical Manual of Mental Disorders , Female , Humans , Male , Phobic Disorders/etiology , Psychometrics , Reproducibility of Results , Retrospective Studies , Sensitivity and Specificity , Severity of Illness Index , Stress Disorders, Post-Traumatic/psychology
16.
Water Res ; 36(17): 4263-72, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12420931

ABSTRACT

Solid-phase micro-extraction has been used for identifying, quantifying and following the evolution of intermediate products of octanol degradation by two advanced oxidation treatments (AOTs), photocatalytic and ultrasound processes, inducing mainly the same active species. Headspace extraction enabled direct extraction of the organic compounds in a heterogeneous process like photocatalysis. The presence of a solid does not affect the extraction percentage of alkanes, alkenes and aldehydes while alcohols and carboxylic acids are not completely extracted if the extraction time is too short. To extract C3-C8 alkanes, alkenes and aldehydes a Carboxen/PDMS fiber and an extraction time of 25 min are used. The presence of alcohol and carboxylic acids requires the use of the presence of salt under acidic conditions, a longer extraction time and a polyacrylate fiber (PA), having a polar fiber. The in situ derivatization--pyrenyldiazomethane on a PA fiber--increases the carboxylic acid extraction containing smaller hydrocarboned chain while diazomethane derivatization is not as efficient due to its volatility. Whatever be the treatment, photocatalysis or ultrasound processes, aldehydes are the main intermediate products, which is not surprising since the same oxidation species (HO2(o), O2(o-), OH(o)) are formed. Alkanes and alkenes are also detected in both processes; however, alkane formation is more important in photocatalysis while alkenes are formed in higher amounts by ultrasound. Moreover, the presence of carboxylic acids in more important amounts by ultrasound than by photocatalysis is attributed to the presence of holes (h+) in photocatalysis which induces photo-Kolbe degradation. The sonochemical formation of small-chained dienes and alkynes is probably due to pyrolysis of hydrophobic compounds in cavitation bubbles.


Subject(s)
1-Octanol/chemistry , 1-Octanol/isolation & purification , Chromatography/methods , Photochemistry , Ultrasonics , Water Purification/methods , Catalysis , Chromatography, High Pressure Liquid , Water Pollutants, Chemical/isolation & purification
17.
Ann Readapt Med Phys ; 45(5): 204-15, 2002 May.
Article in French | MEDLINE | ID: mdl-12020988

ABSTRACT

PURPOSE: To compare the efficiency of two programs of exercise-based rehabilitation that are different for heart rate (HR) training in patients with coronary artery disease: heart rate (HR) according to Karvonen formula (HR training =70% (max HR -rest HR) +rest HR) or HR recorded at the gas exchange ventilatory threshold (VT). TYPE: Controlled randomised clinical trial. SETTING: Cardiovascular rehabilitation unit. METHOD: Twenty-four male patients (54 +/-9.5 years old) with coronary artery disease were allocated at random to one of the two groups: KHR group (n =13) according to Karvonen formula (n =11), and VTHR group according to VT determined by exertion test (n =13). The exercised-based program was similar for all the patients, differing only in HR training (five daily sessions a week for four weeks). Assessment tests were performed at D1 and D28 and included: - an exercise test with measure of HR and double product (HR x blood pressure) at rest, submaximal and maximal intensity, with measure of oxygen consumption and gas exchanges at rest and at maximum exercise; - specific functional tests based on daily life activities; - dyspnea assessment at maximal intensity; - quality of life measurement by SF36. It was taken notice of the drugs taken by the patients, specially betablockers. RESULTS: At inclusion, the two groups were not different for parametric (age, body mass index) and non parametric values (medical or surgical treatment, comorbidity). Even though HR training was significantly different (p <10(-6)), at the end of the program there was a significant increase of power and oxygen consumption at VT (+42.6%, p <10(-6); +18.6%, p <10(-5)) and at maximal intensity (+18.7 %, p <10(-6); 14.2 %, p <10(-5)), but differences between the two groups were not significant; double product was significantly lower at rest (-13.9 %, p <10(-5)) and at submaximal exertion (-10.6 %, p < 10(-3)). Yet, the two groups differed in HR, and HR increased in VTHR group and decreased in KHR, the difference being significant at VT (p =0.05), at submaximal (p =0.037) and maximal exercise (p = 0.05). Dyspnea at maximal intensity was higher in VTHR but SF36 values were not different. DISCUSSION AND CONCLUSION: These results confirm the efficiency of cardiac training program according to Karvonen formula as to ventilatory threshold. However, there is a negative chronotropic effect of cardiac training according to Karvonen formula with a higher intensity, which corresponds to a less cardiac work for a same activity.


Subject(s)
Coronary Artery Disease/rehabilitation , Exercise Therapy , Anaerobic Threshold , Heart Rate , Humans , Male , Middle Aged , Treatment Outcome
18.
Water Sci Technol ; 44(5): 263-70, 2001.
Article in English | MEDLINE | ID: mdl-11695469

ABSTRACT

TiO2 photocatalysis and ultrasound are advanced oxidation processes for water treatment. Our study aimed at showing, via the purposely chosen title compounds, that these techniques can be complementary. For C6H5COCF3 (PTMK), the photocatalytic removal rate was higher than the ultrasonic (515 kHz) removal rate in the presence of TiO2 in the dark, whereas it was the opposite for octan-1-ol under the conditions employed. Simultaneous UV and ultrasound irradiation of the TiO2 suspension led, for PTMK, to a removal rate about equal to the sum of the removal rates observed for separate irradiations, and decreased by a factor of approximately 20% for octan- 1 -ol as if the photocatalytic degradation was suppressed by the dominant distribution of octan-1-ol to the cavitation bubbles. This distribution was substantiated by the large detrimental effect of octan- 1-ol on the PTMK ultrasonic removal rate. The concurrent use of both techniques allowed a faster removal of both pollutants in binary mixtures. The amount of CF3COOH from PTMK was approximately eight times lower in sonicated, than in UV-irradiated, TiO2 suspensions. Several intermediate products showed the occurrence of chemical transformations occurring in and/or on the cavitation bubbles. COD decline and CO2 formation were initially higher for ultrasonic than for photocatalytic treatment. However, complete mineralization (except for CF3COOH) was achieved more rapidly by photocatalysis and even more rapidly by simultaneous use of both techniques.


Subject(s)
1-Octanol/chemistry , Ketones/chemistry , Solvents/chemistry , Titanium/chemistry , Ultrasonics , Water Pollutants , Water Purification/methods , Catalysis , Oxidation-Reduction , Photochemistry
19.
J Biol Chem ; 276(3): 2007-14, 2001 Jan 19.
Article in English | MEDLINE | ID: mdl-11053408

ABSTRACT

To identify new proteins involved in erythropoietin (Epo) signal transduction, we purified the entire set of proteins reactive with anti-phosphotyrosine antibodies from Epo-stimulated UT7 cells. Antisera generated against these proteins were used to screen a lambdaEXlox expression library. One of the isolated cDNAs encodes Gbeta2, the beta2 subunit of heterotrimeric GTP-binding proteins. Gbeta and Galpha(i) coprecipitated with the Epo receptor (EpoR) in extracts from human and murine cell lines and from normal human erythroid progenitor cells. In addition, in vitro Gbeta associated with a fusion protein containing the intracellular domain of the EpoR. Using EpoR mutants, we found that the distal part of the EpoR (between amino acids 459-479) was required for Gi binding. Epo activation of these cells induced the release of the Gi protein from the EpoR. Moreover in isolated cell membranes, Epo treatment inhibited ADP-ribosylation of Gi and increased the binding of GTP. Our results show that heterotrimeric Gi proteins associate with the C-terminal end of the EpoR. Receptor activation leads to the activation and dissociation of Gi from the receptor, suggesting a functional role of Gi protein in Epo signal transduction.


Subject(s)
Heterotrimeric GTP-Binding Proteins/metabolism , Receptors, Erythropoietin/metabolism , Animals , Cytoplasm/metabolism , Erythropoietin/pharmacology , Humans , Mice , Protein Binding , Receptors, Erythropoietin/drug effects , Recombinant Proteins/metabolism , Tumor Cells, Cultured
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