Search PubMed⌕ Search

Biomedical subjects

C Mathieu

Publications and source records attributed to C Mathieu.

At least 163 records · Page 9Linked to original sources
PubMed1989

Improvement of survival and fertilizing capacity of human spermatozoa in an IVF programme by selection on discontinuous Percoll gradients.

Two techniques for the separation of spermatozoa were compared: swim-up migration (SUM) and centrifugation on a discontinuous Percoll gradient (CPG). Their respective effects on sperm motility were analysed by computer-assisted videomicrography in either normal or asthenozoospermic groups. In both groups, there was no difference in any of the motion parameters between the two treatments after 1-h incubation. However, a clear difference was observed after 24 h when excellent motility was retained only in the CPG-treated group. A total of 350 ejaculates were produced by the husbands of women undergoing oocyte retrieval in an IVF programme. Spermatozoa were treated by CPG when the infertility was due to poor quality spermatozoa (n = 91), when there was a known previous history of semen infection (n = 73) or when frozen semen, originating from a donor, was used (n = 36). In all other cases (n = 150), spermatozoa were treated by SUM. The cleavage rates obtained were 32.2, 70.1, 60.9 and 68.6% respectively in the four categories. The clinical pregnancy rates per oocyte retrieval were 19.8, 31.5, 22.2 and 18.0% respectively. Forty-eight births occurred in the CPG group: 28 boys and 20 girls, all normal. We conclude that CPG is useful, both in cases of poor semen quality and in tubal infertility, in which the clinical pregnancy rate increased significantly from 18.0 to 31.5%.

Cell Survival↗
PubMed1988

[Therapeutic use of LH-RH analogs].

The development of GnRH analogues enabling a hypophyseal desensitization with suppression of the gonadotrophic activity has opened new therapeutic possibilities in early puberty of central origin, metastatic prostate and breast cancers, endometriosis, fibromyomas and the syndrome of polycystic ovaries. This retrospective study concerning 93 cycles of in vitro fertilization between March and June 1987, compares the results of the combination of a GnRH agonist (busereline 0.3 mg s.c. x 2 days) with HMGs according to a "long protocol" or a "short protocol". For a mean stimulation time by HMG equivalent (13 days), the number of HMG vials is higher in case of a long protocol (40 vs 30). The mean estradiol level, on the morning of the induction is identical (2,096 pg/ml), as well as the mean number of ovocytes collected (6/tap). The segmentation rate appears to be better in case of long protocol (70% vs 45% in female indications), but there is no significant difference between the pregnancy rates (20 to 30%). The short protocol, less costly and simpler, seems therefore interesting in FIV, with patients without SOPK.

Adult↗
PubMed1988

[Separation of spermatozoa using Percoll gradients: value for in vitro fertilization].

Male infertility can be successfully treated by In Vitro Fertilization (IVF) and Embryo Transfer. However in case of oligo asthenospermia it is often difficult to select enough spermatozoa with good motility for the oocytes insemination. To cope with this problem, in 27 IVF cycles, sperm selection was performed by centrifugation on discontinuous Percoll density gradient. This method was demonstrated to be more efficient than swim-up migration to select motile sperm. The cleavage rate (63%) and the pregnancy rate per cycle (22%) were both satisfying. Centrifugation on discontinuous Percoll gradient was also found to be highly efficient for the removal of bacterial contaminants from semen (20 IVF cycles); the cleavage rate (66%) and the pregnancy rate per cycle (35%) were also quite satisfying. It can be concluded that centrifugation on discontinuous Percoll gradient is a useful method for sperm preparation in IVF in case of oligo-asthenospermia and in case of bacterial contamination in semen.

Cell Separation↗
PubMed1987

[Blood amylase and lipase in diabetic ketoacidosis].

The relation between increase of amylasaemia and increase of lipasaemia was studied during ketoacidosis in 31 insulin-dependent diabetics. The effects of metabolic disturbances on amylase production during the acute phase of ketoacidosis were also evaluated. The greatest increase of amylasaemia was observed after 24 hours in 17 cases (55%), with return to normal values after 3 to 7 days. Amylasuria was closely correlated with amylasaemia (r = 0.7; P less than 0.01). No correlation was found between hyperamylasaemia and the degree of ketoacidosis, but there was a correlation between plasma osmolality and hyperamylasaemia (r = 0.44; P less than 0.02). The increase of lipasaemia, considered more specific of pancreatic damage, was closely correlated with that of amylasaemia (r = 0.63: P less than 0.01). The electrolyte disturbances associated with ketoacidosis are responsible for cellular damage with release of enzymes in many tissues. The hyperamylasaemia consecutive to pancreatic damage might be of similar origin and aggravated by splanchnic hypoperfusion.

Acute Disease↗
PubMed1987

Distribution of nuclear matrix proteins in interphase CHO cells and rearrangements during the cell cycle. An ultrastructural study.

The nuclear matrix contains a group of residual non-histone proteins which remain structurally organized after extensive extraction of isolated nuclei with a high salt buffer, nucleases and a non-ionic detergent. Electron microscopic examination shows that the nuclear matrix is composed of a pore-complex lamina, an intranuclear network and residual nucleoli. In CHO cells biochemical analyses performed by one-dimensional SDS-PAGE show three major nuclear matrix polypeptides with molecular weights between 60 and 70 kDa. Polyclonal antibodies produced against these polypeptides were used to determine their nuclear distribution. Using immunoblotting, these proteins were found in whole nuclei, nuclear matrix, and in the intranuclear network but not in the pore-complex lamina. In order to determine the relationship between these structural proteins and the organization of the nucleus, the proteins were localized in situ. Ultrastructural detection was carried out by immunogold staining of thin sections of Lowicryl K4M-embedded cells. In interphase nuclei all condensed chromatin clumps were labelled. The nucleolus and the interchromatin granules were never immunogold-stained. During mitosis, the label was found to be associated with the chromosomes. This study shows that unlike the lamins, these 60-70 kDa nuclear matrix proteins are associated with the condensed chromatin throughout the cell cycle.

Animals↗
PubMed1987

In vitro behavior of human nonfertile semen in isoosmotic and hyperosmotic media.

High-ionic-strength media are known to favor rapid capacitation and acrosome reaction of spermatozoa in vitro. The influence of isoosmolar (N-BWW) and hyperosmolar (H-BWW) media on the percent motility, forward progression, and zona-free hamster egg penetration has been investigated for 148 semen from patients consulting for male or idiopathic sterility. After 15 h of incubation, the hyperosmotic medium had no significant detrimental effect on the percent motility of spermatozoa, although the forward progression was better maintained in the isoosmolar medium. In general egg penetration was increased when spermatozoa were treated with the hypertonic medium, and in particular 5 patients whose semen showed no penetration when treated with N-BWW scored greater than 12% when treated with H-BWW. For the 23 subjects who had an IVF at the same period, a good agreement with zona-free egg penetration was found in 70% of the cases.

Animals↗
PubMed1986

[Ineffectiveness of hyperbaric oxygen therapy in multiple sclerosis. A randomized placebo-controlled double-blind study].

Seventeen patients with definite and progressive multiple sclerosis entered a double-blind randomized placebo-controlled therapeutic trial of hyperbaric oxygen (HBO). Exposure in monoplace chamber was 90 minutes long each time, 5 days a week, for 4 weeks. The treatment and placebo groups received 100% oxygen at 1.5 bar constant pressure or normal air at 0.1-0.2 bar, respectively. The clinical status of the patients in both groups were compared until one year after treatment. There was no benefit of HBO versus placebo according to the Kurtzke disability status scale. A lesser proportion of patients with deterioration of bowel/bladder function 12 months after therapy was the only benefit of HBO versus placebo according to Kurtzke functional systems scales. On the whole however, HBO is useless in the management of progressive forms of multiple sclerosis.

Double-Blind Method↗
PubMed1986

The use of an immobilised cyclic multi-enzyme system to synthesise branched penta- and hexa-saccharides associated with blood-group I epitopes.

The branched hexasaccharide beta-D-Galp-(1----4)-beta-D-GlcpNAc-(1----3)- [beta-D-Galp-(1----4)-beta-D-GlcpNAc-(1----6)]-beta-D-Galp-(1----4)-beta -D- GlcOMe (1) was obtained on a 0.1-mmol scale by enzymic bigalactosylation of the tetrasaccharide beta-D-GlcpNAc-(1----3)-[beta-D-GlcpNAc-(1----6)]-beta-D-Galp-(1----4)-b eta- D-GlcOMe by the use of an immobilised multi-enzyme system which regenerated UDP-alpha-D-galactose in situ. The formation of 1 proceeded in two steps. An intermediate compound was identified on the basis of 1H- and 13C-n.m.r. data as the pentasaccharide beta-D-GlcpNAc-(1----3)-[beta-D-Galp-(1----4)-beta-D-GlcpNAc-(1----6)]-b eta- D-Galp-(1----4)-beta-D-GlcOMe.

Blood Group Antigens↗
PubMed1984

Acetylcholine metabolism by cultured neurons from rat nodose ganglia: regulation by a macromolecule from muscle-conditioned medium.

Acetylcholine metabolism has been studied in primary cultures of neurons dissociated from newborn rat nodose ganglia. Neither nerve growth factor nor muscle-conditioned medium had any detectable effect on the long-term survival of these neurons, which appeared well differentiated upon phase-contrast and electron microscopic examination. [3H]Acetylcholine synthesis and accumulation by 2-3-week old nodose cultures and choline acetyltransferase activity were increased (2.0 +/- 0.15)-fold and (2.0 +/- 0.48)-fold, respectively, upon growth with muscle-conditioned medium, whereas acetylcholinesterase was decreased (1.5 +/- 0.1)-fold (means +/- SEM, n = 5-9). The same effects were observed when comparing nodose cultures grown in the presence of proteins purified from conditioned medium in four fractionation steps. This purified material had no effects on the protein content of the cultures, or on lactate dehydrogenase activity, and thus did not affect the overall growth of the cultures. We demonstrate that this factor copurifies with a factor(s) involved in the regulation of choline acetyltransferase and acetylcholinesterase in neuron cultures from newborn rat superior cervical ganglia [Swerts, Le Van Thai, Vigny and Weber (1983) Devl Biol. 100, 1-11] and from embryonic day 13 rat embryo spinal cord [Giess and Weber (1984) J. Neurosci. 4, 1442-1452]. Although the cholinergic factor from muscle-conditioned medium has not been purified to homogeneity, the data suggest that the same extracellular, macromolecular factor may be involved in the regulation of acetylcholine metabolism in derivatives from the neural crest, the neural tube and the epibranchial placodes.

Acetylcholine↗