Fatigue and physical disability in patients with multiple sclerosis: a structural equation modeling approach

Although fatigue is one of the most common and disabling symptoms in patients with multiple sclerosis (MS), its pathogenesis is still poorly understood and it is difficult to treat. The aim of the current study was to test the assumptions of a cognitive-behavioral model that explains fatigue and physical disability in MS patients, by comparing this approach with a more traditional biomedical approach. Structural equation modeling was applied to a sample of 262 MS patients. Neither the cognitive-behavioral, nor the biomedical model showed an adequate fit of our data. The modification indices supported an integration of both models, which showed a better fit than those of the separate models. This final model, is notable for at least three features: (1) fatigue is associated with depression and physical disability, (2) physical disability is associated with disease severity and fatigue-related fear and avoidance behavior, and (3) catastrophic interpretations about fatigue, fueled by depression, mediated the relationship between fatigue and fatigue-related fear and avoidance behavior. Our results suggest that an integrated approach, including the modification of catastrophic thoughts about fatigue, would be beneficial in the treatment of fatigue in MS patients

Etude de la condensation d'azotures de glycosyle avec quelques dérivés acétyléniques

Doctorat en Sciencesinfo:eu-repo/semantics/nonPublishe

Influence of divalent cations on androgen and estrogen binding in human prostatic tissue

SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Assessment of different isolation procedures for blastomeres from two-cell mouse embryos

As an extension of in-vitro fertilization and embryo transfer, detection of genetic and metabolic defects prior to implantation might be possible in the future. The objective of pre-implaiitation diagnosis would be to sample a minimal amount of cellular material of the conceptus for diagnosis prior to transfer. Different protocols for isolating individual blastomeres from two-cell mouse embryos were evaluated. Two-cell mouse embryos were collected and the zona pdlucida was removed by enzyme treatment (pronase), by exposure to acid Tyrode (pH = 2.5) or by mechanical force (suction into a small pipette, removal with a microblade). Individual blastomeres were obtained by exposure to a chelating agent (EDTA-glycme mixture), to Ca 2+-Mg 2+-free PBS or after isolation by mechanical force (bisection with a microblade or suction in a small pipette). The isolated blastomeres were then cultured in vitro without zonae pellucidae. All isolation procedures had a negative impact on the growth patterns of the isolated blastomeres. Different abnormalities could be observed at the blastocyst stage including embryos lacking visible compaction features, embryos with double blastocoeJk cavities and embryos with no inner cell mass (trophoblastic vesicles). © 1987 IRL Press Ltd.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Estradiol- and estriol-binding in human benign prostatic hyperplasia.

Binding of the natural estrogens, estradiol and estriol, was investigated, in 34 samples of human benign prostatic hypertrophy (BPH) tissue, using Scatchard analysis and agar gel electrophoresis. Saturation binding analysis using a wide range of concentrations of both ligands resulted in curvilinear Scatchard plots. This confirmed the presence of two binding forms for estradiol: a true estrogen receptor, and a protein with lower affinity and higher capacity. Both binding species were also demonstrated and quantified with estriol. The electrophoretic process, after incubation at low and high ligand concentrations also resulted in separation, for both estrogens, of two binding peaks. They are probably two distinct forms of the low affinity, high capacity binding measured by Scatchard. The procedure used in our laboratory was not able to provide accurate determination of the concentrations of these binding forms. Possible modifications to alleviate these drawbacks are discussed.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Analysis of the low affinity high capacity estrogenic binding in human benign prostatic hypertrophy.

The binding of estradiol in extracts of human benign prostatic hypertrophy (BPH) tissue was studied using the agar gel electrophoretic method. Two distinct binding peaks were observed having the same high specificity for natural estrogens and very poor affinity for the other classes of steroids as well as for diethylstilbestrol (DES). Therefore, it is highly probable that these peaks are two different forms of the low affinity binding protein present in human prostate. Cytosols were shown to contain smaller amounts of the binding proteins than the tissular extracts. This difference probably resulted from protein degradation occurring during the time required to prepare the cytosol. The concentrations of the extract and of the radiolabeled ligand, the composition of the buffer, the addition of sodium molybdate, sodium tartrate or proteolytic inhibitors, were evaluated in order to delineate optimal binding conditions. The possible function of these low-affinity high-capacity binding proteins is discussed.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Steroid receptors in the human prostate. Detection of tissue specific androgen binding in prostate cancer

The authors searched for tissue specific binding of 5α androstan 17β ol 3 one (5α dihydrotestosterone; 5α DHT) in cytosols prepared from 25 surgically obtained benign prostatic hypertrophy (BPH) samples and in 3 tissue specimens containing prostate cancer cells. The distinction between steroid receptor complexes and ligand binding to serum sex hormone binding globulin (SHBG) was facilitated by combination experiments involving both sucrose gradient ultracentrifugation and agar gel electrophoresis. Gradient analysis of a cytosol prepared from a cercical lymph node (CLN) contaning metastatic prostate tissue, revealed both 8 S and 4 S forms of high affinity (charcoal stable) 5α [3H]DHT binding. When electrophoresis was performed on gradient fractions from these zones, anodally migrating steroid receptor complexes were found only in the 8 S peak, the 4 S region containing radioligand bound to cathodally directed SHBG. In similar experiments with two BPH samples heavily invaded with prostate cancer cells, only a single 4 S peak of radioligand binding was detected. Its multicomponent nature was uncovered electrophoretically when, in addition to SHBG, saturable, androgen binding molecules appeared anodally. Their incomplete resolution from SHBG on a gradient might have prevented their identification had this been the only method used. In contrast to the cancer containing tissues, no saturable 5α [3H]DHT binding, other than that to SHBG, was detected in any of the BPH samples analysed. It is considered that, of the methods currently available, agar gel electrophoresis may be particularly useful for further investigations into the possible multicomponent nature of androgen binding of tissue origin in the human prostate.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Analysis of the androgen binding in human benign prostatic hypertrophy

In order to delineate optimal conditions for the determination of androgen specific binding in human benign prostatic hypertrophy tissues (BPH), extracts of these tissues were prepared using buffers of different compositions. The binding of 5α-dihydrotestosterone (DHT) and of methyltrienolone (R 1881) was analyzed using agar gel electrophoresis. This method allowed the detection of 3 different high affinity tissular binding peaks with similar specificity. Moreover, the inhibition by each of the competitors was also the same for both ligands. It could be demonstrated that none of the observed peaks resulted from the binding of 1 of the ligands to sex hormone binding globulin (SHBG) or to a progesterone receptor. Hypotheses about the possible origin of this peaks are discussed.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Steroid receptors in human prostate cancer

SCOPUS: NotDefined.jinfo:eu-repo/semantics/publishe

Steroid receptors in the human prostate. 2. Some properties of the estrophilic molecule of benign prostatic hypertrophy

Some physicochemical properties of the estrophilic 'receptor' of human benign prostatic hypertrophy were examined by agar gel electrophoresis. 1) Competition analyses revealed the high selectivity of the molecule for the naturally occurring estrogens but not for representatives of other classes of steroid hormones (androgens, corticosteroids, progesterone). This, coupled with the failure of an estrogen 'receptor'-rich extract to exhibit detectable tissue specific binding of (3H) 5α-dihydrotestosterone suggests that prostatic androgen and estrogen receptors may have separate identities. 2) The molecule proved highly resistant to enzyme attack, a stability conferred by estradiol-17β rather than by the thiol reagent dithiothreitol. Its proteinaceous nature was finally demonstrated when extract was exposed to enzymes at 0°C prior to steroid addition. 3) Initial complex formation between estrogen and its 'receptor' protein was rapid and reached a plateau after 4 hours. Binding was greater at 0°C than 37°C. © 1976.SCOPUS: ar.jinfo:eu-repo/semantics/publishe