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131.

Material and methods

The study population consisted of 39 subjects divided into two groups: 21 azoospermic males and 18 oligoazoospermic males. These men were selected in andrology departments over a period of six months. The andrology and liaison psychiatry departments of Lille university hospital established a general infertility questionnaire. This semi-structured questionnaire comprising 40 questions was based on clinical experience and describes the clinical and symptomatic context of infertility. An individual 50-item questionnaire was then used to analyse the psychosocial, marital and sexual effects of male infertility and the representation of the psychiatrist in the andrology department.

Results

One third of patients discovered the diagnosis of infertility when the biologist gave them the results of the semen analysis. Our patients initially envisaged marital, psychological and social problems, but very few sexual problems. They imagined that infertility was more disturbing for women than for men, from a psychological and sexual point of view. 82% of our subjects imagined that their partner had no sexual problems. 48.7% of them thought that their partner had no psychological difficulties related to their infertility. The oligoasthenospermia group considered that the partner had significantly more “psychological difficulties” compared to the azoospermia group. 41% of our patients felt guilty towards their partner because of their infertility diagnosis. 10.3% of patients presented sexual disorders before the diagnosis of male infertility and 25.6% presented sexual disorders after this diagnosis. Contrary to data in the literature, a major change of sexuality was not observed in the majority of the couples after the diagnosis. When sexuality changed, it generally consisted of a reduction of the frequency of sexual relations. Among the patients who reported sexual difficulties, only 40% related them to infertility. 50% did not report any relationship between the psychological difficulties related to infertility and the sexual difficulties. Contrary to the data in the literature, neither the loss of spontaneity during sexual relations, nor the complementary investigations necessary for artificial insemination had any influence on sexuality. 89.8% of our patients are ready to change their sexual practices in order to be more fertile without causing any sexual or psychological problems. However, only 34.3% of patients reported a concern about reproductive efficacy during sexual relations. A more marked sexuality/reproduction dissociation was observed in oligoazoospermic males than in azoospermic males. 28.2% of patients reported that talking about their sexual and/or psychological problems with a psychiatrist was helpful.

Conclusion

Many contradictions and underestimations were observed in the answers to the questions. We confirmed the existence of a psychological and sexual distress, but which was quantitatively less severe than that described in “gynaecological” populations. However, a real psychological and sexual distress does exist in our population, which is why we propose from the outset a psychosomatic and sexological treatment of infertility in order to prevent the onset of these sexual difficulties. Our questionnaire was based on clinical experience and helped our patients to identify their psychological and sexual difficulties related to infertility and its treatment. It would therefore be useful for the practitioner, andrologist or psychiatrist, to help the patient express the effects related to this “new medicalized sexuality”.  相似文献   
132.
The symbiotic hydrothermal vent tubeworm Riftia pachyptila needs to supply its internal bacterial symbionts with carbon dioxide, their inorganic carbon source. Our aim in this study was to characterize the carbonic anhydrase (CA) involved in CO(2) transport and conversion at various steps in the plume and the symbiotic tissue, the trophosome. A complete 1209 kb cDNA has been sequenced from the trophosome and identified as a putative alpha-CA based on BLAST analysis and the similarities of total deduced amino-acid sequence with those from the GenBank database. In the plume, the putative CA sequence obtained from cDNA library screening was 90% identical to the trophosome CA, except in the first 77 nucleotides downstream from the initiation site identified on trophosome CA. A phylogenetic analysis showed that the annelidan Riftia CA (CARp) emerges clustered with invertebrate CAs, the arthropodan Drosophila CA and the cnidarian Anthopleura CA. This invertebrate cluster appeared as a sister group of the cluster comprising mitochondrial and cytosolic isoforms in vertebrates: CAV, CAI II and III, and CAVII. However, amino acid sequence alignment showed that Riftia CA was closer to cytosolic CA than to mitochondrial CA. Combined biochemical approaches revealed two cytosolic CAs with different molecular weights and pI's in the plume and the trophosome, and the occurrence of a membrane-bound CA isoform in addition to the cytosolic one in the trophosome. The physiologic roles of cytosolic CA in both tissues and supplementary membrane-bound CA isoform in the trophosome in the optimization of CO(2) transport and conversion are discussed.  相似文献   
133.
Spectroscopic methods were used to monitor the unfolding of the leucine specific (LS) and the leucine-isoleucine-valine (LIV) binding proteins. Our studies indicate that ligand-free protein undergoes a simple two-state unfolding, whereas the protein-ligand complex undergoes a three-state unfolding model. Ligand binding causes significant stabilization of both proteins. There is correlation between ligand hydrophobicity and protein stabilization: the most hydrophobic ligand, isoleucine, causes the most significant stabilization of LIV protein. A disulfide bond present in N-domain of both proteins makes a large contribution to the protein stability of these periplasmic binding receptors.  相似文献   
134.
135.
Polymerization of members of the serpin superfamily underlies diseases as diverse as cirrhosis, angioedema, thrombosis and dementia. The Drosophila serpin Necrotic controls the innate immune response and is homologous to human alpha(1)-antitrypsin. We show that necrotic mutations that are identical to the Z-deficiency variant of alpha(1)-antitrypsin form urea-stable polymers in vivo. These necrotic mutations are temperature sensitive, which is in keeping with the temperature-dependent polymerization of serpins in vitro and the role of childhood fevers in exacerbating liver disease in Z alpha-antitrypsin deficiency. In addition, we identify two nec mutations homologous to an antithrombin point mutation that is responsible for neonatal thrombosis. Transgenic flies carrying an S>F amino-acid substitution equivalent to that found in Siiyama-variant antitrypsin (nec(S>F.UAS)) fail to complement nec-null mutations and demonstrate a dominant temperature-dependent inactivation of the wild-type nec allele. Taken together, these data establish Drosophila as a powerful system to study serpin polymerization in vivo.  相似文献   
136.
This paper demonstrates potential applications of two periplasmic receptor proteins from E. coli as sensing elements for biosensors using the surface plasmon resonance (SPR) technique. These molecules, namely the aspartate to cysteine mutant of the leucine-specific receptor (LS-D1C) and the glutamine to cysteine mutant of the D-glucose/D-galactose receptor (GGR-Q26C) proteins, are chemisorbed on a thin (approximately 40 nm) Au film in neutral K2HPO4 buffers. Using angle and time resolved SPR measurements; we show that adsorption behaviors of both proteins are dominated by diffusion-free second order Langmuir kinetics. We also show that the protein-modified Au films exhibit measurable SPR shifts upon binding to their respective target ligands. According to these SPR data, the kinetics of ligand binding for both LS-D1C and GGR-Q26C are governed by irreversible first order diffusion limited Langmuir model. The utility of the SPR technique for studying reactions of biological molecules is further illustrated in this work.  相似文献   
137.
A detailed analysis of the periplasmic electron carriers of the photosynthetic bacterium Ectothiorhodospira sp. has been performed. Two low mid-point redox potential electron carriers, cytochrome c′ and cytochrome c, are detected. A high potential iron–sulfur protein is the only high mid-point redox potential electron transfer component present in the periplasm. Analysis of light-induced absorption changes shows that this high potential iron–sulfur protein acts in vivo as efficient electron donor to the photo-oxidized high potential heme of the Ectothiorhodospira sp. reaction center. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
138.
M C Shastry  S D Luck    H Roder 《Biophysical journal》1998,74(5):2714-2721
A continuous-flow capillary mixing apparatus, based on the original design of Regenfuss et al. (Regenfuss, P., R. M. Clegg, M. J. Fulwyler, F. J. Barrantes, and T. M. Jovin. 1985. Rev. Sci. Instrum. 56:283-290), has been developed with significant advances in mixer design, detection method and data analysis. To overcome the problems associated with the free-flowing jet used for observation in the original design (instability, optical artifacts due to scattering, poor definition of the geometry), the solution emerging from the capillary is injected directly into a flow-cell joined to the tip of the outer capillary via a ground-glass joint. The reaction kinetics are followed by measuring fluorescence versus distance downstream from the mixer, using an Hg(Xe) arc lamp for excitation and a digital camera with a UV-sensitized CCD detector for detection. Test reactions involving fluorescent dyes indicate that mixing is completed within 15 micros of its initiation and that the dead time of the measurement is 45 +/- 5 micros, which represents a >30-fold improvement in time resolution over conventional stopped-flow instruments. The high sensitivity and linearity of the CCD camera have been instrumental in obtaining artifact-free kinetic data over the time window from approximately 45 micros to a few milliseconds with signal-to-noise levels comparable to those of conventional methods. The scope of the method is discussed and illustrated with an example of a protein folding reaction.  相似文献   
139.
140.
Chemotaxis and phagocytosis are basically similar in cells of the immune system and in Dictyostelium amebae. Deletion of the unique G protein β subunit in D. discoideum impaired phagocytosis but had little effect on fluid-phase endocytosis, cytokinesis, or random motility. Constitutive expression of wild-type β subunit restored phagocytosis and normal development. Chemoattractants released by cells or bacteria trigger typical transient actin polymerization responses in wild-type cells. In β subunit–null cells, and in a series of β subunit point mutants, these responses were impaired to a degree that correlated with the defect in phagocytosis. Image analysis of green fluorescent protein–actin transfected cells showed that β subunit– null cells were defective in reshaping the actin network into a phagocytic cup, and eventually a phagosome, in response to particle attachment. Our results indicate that signaling through heterotrimeric G proteins is required for regulating the actin cytoskeleton during phagocytic uptake, as previously shown for chemotaxis. Inhibitors of phospholipase C and intracellular Ca2+ mobilization inhibited phagocytosis, suggesting the possible involvement of these effectors in the process.  相似文献   
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