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Biomedical subjects

J Auger

Publications and source records attributed to J Auger.

At least 19 recordsLinked to original sources
PubMed1992

In vitro DNA fluorescence after in vitro fertilization (IVF) failure.

PURPOSE: A pilot study was performed to test the diagnostic value of in vitro DNA fluorescence in oocytes that failed to fertilize after IVF. Ten patients with a cleavage rate less than 20% after IVF were included. RESULTS: Uncleaved oocytes were observed by fluorescence microscopy after incubation with the DNA fluorescent dye Hoeschst 33342. Four main causes which may have contributed to the low cleavage rate were found: (1) sperm incapacity to penetrate the oocyte despite the absence of the usual criteria for male infertility, (2) oocyte immaturity, (3) delayed fertilization, and (4) oocyte abnormalities revealed by aberrations in the morphology of the female chromatin. CONCLUSIONS: The possibility of a rapid and detailed analysis of the maturational status of unfertilized oocytes, the morphology of the female chromatin, the presence and quantity of spermatozoa tightly bound to the zona pellucida, and sperm penetration into the oocyte without subsequent pronucleus formation, using DNA fluorescence, allows us to clarify further the cause of fertilization failure and to orient infertility treatment toward the male, the female, or both partners.

Adult↗
PubMed1992

Process safety.

Explore the source record for details and available documents.

Accidents, Occupational↗
PubMed1990

Motion of individual human spermatozoa, both normal and lacking the outer dynein arms, during a continuous temperature rise.

The effect of increasing temperature from 22-25 degrees C to 37 degrees C on various motion characteristics of individual normal human spermatozoa and spermatozoa lacking the outer dynein arms (LODA) was studied by using a new automatic microscopic tracking method. It was found that: 1) The curvilinear velocity (Vc, measured between 1-3 sec) of both normal and LODA spermatozoa, fluctuated more or less intensely between spermatozoa; this fluctuation was not thermodependent. 2) The average Vc in the two groups of spermatozoa increased with the rise in temperature at a similar rate (1 micron/sec/degrees C), but LODA spermatozoa had an initial Vc lower than that of normal spermatozoa (12.5 +/- 5.3 microns/sec and 34.2 +/- 8.2 microns/sec, respectively). 3) The profile of the Vc increase associated with the temperature rise was different for the two groups of spermatozoa: for LODA spermatozoa it was linear between 25-37 degrees C, whereas for normal spermatozoa a plateau was reached at about 31 degrees C. 4) Various patterns of trajectory were found for both normal and LODA spermatozoa; these patterns were unrelated to temperature. However, LODA spermatozoa had more linear trajectories than normal spermatozoa. 5) Plots derived from reaction rate theory showed that the activation enthalpy, delta H was a function of the increase of Vc for both normal and LODA spermatozoa, but that delta H was higher for LODA spermatozoa.

Adenosine Triphosphatases↗
PubMed1990

Chlorophyll a fluorescence measurements of isolated spinach thylakoids obtained by using single-laser-based flow cytometry.

Flow cytometry data of spinach thylakoid membrane preparations indicate the presence of a homogeneous thylakoid population. Fluorescence data from a flow cytometer and comparison with data from two other fluorometers show that chlorophyll a fluorescence detected with a flow cytometer has the character of maximum fluorescence (Fmax), not of the constant component (Fo). This conclusion is important since Fo measures fluorescence that is affected mostly by changes in excitation energy transfer and Fmax-Fo (the variable fluorescence) by changes in photochemistry. This was demonstrated by: 1) The light intensity as well as diffusion rate dependence of the quenching effect of various quinones (p-benzoquinone, phenyl-benzoquinone, and 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone, DBMIB) on fluorescence yield; quenching for the same concentration of these quinones was lower at the higher than at the lower light intensities. 2) Temperature dependence of the fluorescence yield; increasing the temperature from 20 to 70 degrees C did not show an increase in fluorescence yield using a flow cytometer in contrast to measurements with weak excitation light, but similar to those obtained for Fmax. 3) Addition of an inhibitor diuron up to 100 microM did not change the fluorescence intensity. A comparison of quenching of fluorescence by various quinones obtained by flow cytometry with those by other fluorometers suggests that the high intensity used in the cytometry produces unique results: the rate of reduction of quinones in much larger than the rate of equilibration with the bulk quinones.

Chlorophyll↗
PubMed1990

Aniline blue staining as a marker of sperm chromatin defects associated with different semen characteristics discriminates between proven fertile and suspected infertile men.

A retrospective study of 49 men with proven fertility and 396 suspected infertile men was conducted with the primary objective of investigating the relationship between the nuclear maturity of sperm and male fertility. Acidic aniline blue staining was used to detect chromatin defects of sperm nuclei related to their nucleoprotein content as associated with DNA. The discriminant value of the percentage of unstained nuclei (= percentage of mature heads, MH) and of other semen characteristics, was analysed by a stepwise (forward) linear regression model. Semen characteristics that discriminated significantly between the two groups of subjects were, in descending order: (1) the percentage of normal sperm, (2) the percentage of amorphous heads, (3) the percentage of tapered heads, (4) semen volume, and (5) the percentage of MH. The discriminant value of each of the significant characteristics was studied by means of ROC-curves. MH had the best ROC-curve profile; its cut-off value was found to be equal to 70% (74.5 +/- 2.6% for the donor group versus 53.0 +/- 1.1% for the patient group). A simple infertility score (SIS) including MH, was built according to the cut-off values inferred from the ROC-curves. SIS allowed an overall satisfactory separation of the two groups (less than or equal to 4 = fertile, 5-6 = uncertainty zone, greater than 6 = infertile). Our results indicate that the addition of the evaluation of sperm head maturity to routine semen analysis improves the assessment of fertility in men.

Aniline Compounds↗
PubMed1990

Flow and image cytometry for quality assessment of fresh and frozen human sperm samples.

A previous study reported that sperm mitochondrial activity and sperm motility can be evaluated by combined flow and image cytometry, suggesting their potential interest in fertility clinical applications and for studying the effect of physical and chemical agents that modify sperm motility and/or metabolism. This paper focuses on the effect of freezing sperm in liquid nitrogen, extensively used in artificial insemination (AI), combined with different sperm manipulations (washing, swim-up in capacitating medium, CM) using flow and image cytometry on sperm samples from three fertile donors. Rhodamine 123 (Rh123) uptake profiles were bimodal both for fresh and frozen/thawed samples. The mean value of fluorescence of active cells (m+) remained nearly similar after freezing while the percentage of active cells (%C+) was significantly decreased and the percentage of dead cells (%dc, revealed by propidium iodide uptake) significantly increased. In all experiments, the decrease of MOT (percentage of motile sperm) due to freezing was concomitant, to a smaller extent, with a drop in %C+ and an increase in %dc; there was a good relationship between velocity (VCL, VSL) or trajectory characteristics (ALH) and the mean fluorescence values of active cells (m+). Sperm immobilization was neither found related to a major decrease of Rh123 fluorescence nor to an increase in dead cells.

Cryopreservation↗
PubMed1988

Measurement of spermatozoal motility over prolonged periods of time using image analysis.

This paper presents a new method for the quantitative analysis of the movement characteristics of spermatozoa. The method is based on (i) measuring the displacement of a spermatozoon observed using a microscope and (ii) automatically compensating for the displacement of the spermatozoon in order to keep it in the center of the microscopic field. The displacement of the spermatozoon is measured by on-line processing of digitized images of the microscopic field, acquired by an image analysis system. The motility characteristics of the same spermatozoon can be evaluated over prolonged periods of time (typically 10 min). The movement characteristics of 19 spermatozoa from five fertile donors were studied. At constant temperature, intradonor variations of the motility parameters were found. No statistically significant differences were found in the mean values of the motility characteristics for three of four donors. At increasing temperature, the mean curvilinear velocity, averaged on the 19 spermatozoa from the five donors, regularly increased between 23 and 30 degrees C and remained constant up to 38 degrees C.

Algorithms↗
PubMed1988

Computerized sperm motility and application of sperm cryopreservation.

An objective method for measuring sperm motion characteristics was developed on an Intellect 100 Quantel Image Analysis System suitable for various image cytometric applications. It provided overall analysis of percent motility (% MS) as well as individual and mean measurements of motion characteristics, including vigor characteristics such as curvilinear velocity (Vc), straight line velocity (Vsl), and trajectory pattern characteristics, that is, progressiveness ratio (PR) and amplitude of lateral head displacement (Alh). Evaluation of the method for reproducibility and accuracy showed reliable measurements of these parameters measured on a minimum of 70 motile sperm, sufficient to describe adequately the sperm population. A study was performed comparing motion characteristics of 30 semen samples falling in a normal range before and after cryopreservation in cryoprotector medium (CM). A mean motility rate of recovery (MRR) of 45% was obtained. Only sperm count and concentration in motile forms among initial semen variables correlated weakly with MRR. Velocity recovery rate (VRR) approached 1 with a marked variability among ejaculates. Distribution profile of Vc was highly modified by freezing in CM: spermatozoa that were initially fast and progressive were the most resistant to cryoaggression. PR and Alh values were little affected by freezing in CM. The tolerance of various samples from a given patient was highly variable for % MS and Alh and less variable for Vc and PR. This illustrates the difficulty in predicting the effect of freezing on motility characteristics and, therefore, of extrapolating from semen variables the ability of frozen-thawed samples to fertilize.

Freezing↗
PubMed1987

Integration and expression of provirus in human cells transformed by avian sarcoma virus.

Previously, human diploid fibroblasts from some donors infected in vitro by avian sarcoma virus (ASV) were transformed and found, by electron microscopy, to produce small numbers of virus particles that were infectious by bioassay; also, a line of human osteosarcoma cells infected with ASV developed additional characteristics of transformation and released a small number of infectious virus particles. In this study the complete proviral sequence was shown to be integrated in the genome of these cells. The env-related proteins gp85 and gp37 and the gag-related proteins pr76, pr60, and p19 can be detected in cytoplasmic extracts of ASV-infected human cells. Comparable amounts of pp60v-src were found in human and avian cells infected with ASV. The associated kinase activity in infected human cells was dramatically increased as compared to that of uninfected controls; the enzyme had the same cation and substrate requirements as those from ASV-transformed avian cells. Replicating particles from infected human cells were purified and were significantly modified compared to those from avian hosts as shown by a) higher specific gravity, b) the presence of RSV gag-related but not env-related antigens, and c) the fact that the virus-associated reverse transcriptase preferred the divalent cations Mn2+ and Fe2+ over Mg2+.

Antigens, Viral↗
PubMed1986

Genetic screening for artificial insemination by donor (AID). Results of a study on 676 semen donors.

We report the results of our ten-year experience in the Centre for Study and Conservation of Human Semen (CECOS) in Paris-Bicêtre. A total of 676 potential semen donors were interviewed by a geneticist and karyotyped; 6.0% were excluded, i.e. 2.6% for a cytogenetic reason and 3.4% for a genic reason. Our experience stresses the subjectivity and difficulty of the exclusion decision. It also shows how useful it is to take into account the recipient's familial pathology when choosing the donor. Finally, it reveals the importance of the geneticist's participation in the functioning of a centre.

Chromosome Aberrations↗
PubMed1986

Comparative study of automated morphometric and semiquantitative estimations of alcoholic liver steatosis.

Needle biopsy of the liver is of great value in appreciating the intensity, type and topography of the steatosis commonly observed during chronic alcoholic diseases. The usual semiquantitative optical analysis is very inaccurate and depends on the subjectivity and training of the pathologist. We therefore performed an automated analysis of liver steatosis using a QTM 720 image analyzer connected to a PDP 11/34 minicomputer. Visual control of the results of the automated analysis showed it to give good results: 94% of the droplets were detected and only 10% of the patterns automatically selected were not droplets. Eight normal biopsies and 37 biopsies showing alcoholic liver steatosis were analyzed. The automated morphometric analysis calculated the mean density (percentage) of steatosis and the size distribution of the droplets. Statistical comparison of these results with those of the semiquantitative optical analysis performed independently by two pathologists showed a significant correlation between their calculations of the density/degree of steatosis but significant differences for their evaluation of the type of steatosis. The pathologists constantly overestimated the ratio of macrodroplets to microdroplets.

Biopsy, Needle↗
PubMed1978

Actin may be present on the lymphocyte surface.

Lymphocytes were assessed for the presence of surface actin and myosin by lactoperoxidase-catalyzed iodination and indirect immunofluorescence using antisera against purified pig skeletal muscle actin and pig smooth muscle myosin. Sodium dodecyl sulfate/polyacrylamide gel electrophoresis of 125I-labeled pig, mouse, and human B lymphocytes revealed an intense radioactive band of 43,000 molecular weight, whereas pig and mouse T lymphocytes gave a much less intense band. This band comigrated with actin, was nonglycosylated as judged by lack of binding to lentil lectin-Sepharose, was bound specifically by myosin fibers, and could be distinguished from a polypeptide of similar mobility derived from the major histocompatibility antigens. These results suggest that actin is present on the surface of B lymphocytes and, to a lesser extent, on T lymphocytes. Pig, mouse, and human Ig-bearing cells were stained by antiactin and antimyosin antisera, as judged by indirect immunofluorescence, whereas non-Ig-bearing cells were not stained. Antibody binding, however, was depleted by adsorbing the antisera with Ig-Sepharose. It was concluded that the immunofluorescence results are misleading and reflect the presence of antibodies that crossreact with Ig.

Actins↗
PubMed1977

Mechanism of lymphocyte activation: the binding of phytohemagglutinin to the lymphocyte surface.

The dynamics of phytohemagglutinin (PHA)-lymphocyte interaction was studied using 125I-labeled PHA (leucoagglutinin) and pig mesenteric lymph node lymphocytes that had been depleted of erythrocytes, dead cells, adherent cells and immunoglobulin-bearing cells. Evidence was obtained that PHA stimulated the majority of the lymphocytes to transform. Binding of PHA at 37 degrees C was fairly rapid (rate constant for association: 2.6 X 10(5) M-1 sec-1), saturable, reversible and specifically inhibited by N-acetylgalactosamine (Kdiss: 3 X 10(-4) M) and unlabeled PHA. A Scatchard plot was curvilinear and gave evidence for 3.6 X 10(5) binding sites per cell comprising 8.7% of high affinity sites (Kdiss: 3.7 X 10(-9) M) and 91.3% of lower affinity (Kdiss: 1.4 X 10(-7) M). About 20% of the sites were occupied under culture conditions giving maximal transformation. Alternative explanations for the curvilinear plot included negative cooperative interactions and/or increase in affinity through multivalent interaction. Negative cooperativity was supported by the demonstration that free PHA promoted the dissociation of bound PHA. Binding was not affected by metabolic inhibitors, and binding to purified lymphocyte plasma membrane resembled that to whole cells. These results suggested that PHA binding to whole lymphocytes was not grossly influenced by "capping", endocytosis and shedding.

Acetylgalactosamine↗
PubMed1975

Recognition at cell surfaces: phytohaemagglutinin-lymphocyte interaction.

Many aspects of cell behaviour are regulated by the interaction of extracellular ligands with specific receptors exposed on the cell surface. The receptors correspond to membrane proteins and expecially glycoproteins. A key event in regulation is the transmission across the surface membrane of the information resulting from receptor-ligand interaction. The activation of lymphocytes by Phaseolus vulgaris phytohaemagglutinin (PHA) provides a convenient experimental model for the study of the molecular basis of receptor-ligand interaction and the molecular consequences of interaction. The receptor mediating lymphocyte activation by PHA is probably a unique glycoprotein which is present to the extent of about 3 X 10(4) molecules/cell. The PHA-receptor complex solubilized in 1% sodium deoxycholate has a molecular size of about 3 X 10(5). The primary event in the activation process is probably an increase in the permeability of the surface membrane to Ca2+. This may be achieved by PHA cross-linking ('patching') the receptors to form a polar channel that permits an influx of Ca2+.

Animals↗
PubMedDate not supplied

Multiple-dose pharmacokinetics of the new H1-receptor antagonist tazifylline in healthy volunteers.

The multiple-dose pharmacokinetics of the new H1-receptor antagonist, tazifylline, were investigated in healthy volunteers. From single-dose data, tazifylline appeared to be rapidly absorbed (median tmax of 0.6 h) and eliminated (t1/2 = 1.0 +/- 0.2 h). However, plasma levels measured on days 3 and 8 of the multiple-dose regimen (10 mg b.i.d. for 8 days) indicated moderate accumulation. A two-compartment model best described multiple-dose data with a terminal half-life of 15.6 +/- 7.6 h consistent with twice-daily dosing of tazifylline.

Adult↗
PubMedDate not supplied

Human sperm mitochondrial function related to motility: a flow and image cytometric assessment.

Current evaluation of male fertility, routinely estimated by sperm count, motility, and morphology, provides only crude information about the fertility state of individuals. Both flow and image cytometry were applied to mitochondrial activity and sperm motility respectively. Sperm samples from fertile donors were concomitantly measured for Rhodamine 123 (Rh123) uptake (an estimation of mitochondrial activity), percentage of dead cells, and motility characteristics, such as percentage of motility, curvilinear velocity, and amplitude of lateral head displacement. These measurements were done under experimental conditions known to modulate sperm motility (temperature and time course survival in a capacitating medium). Bimodal distributions were found for Rh123 uptake. Flow cytometry-derived parameters were essentially time-dependent whereas motility characteristics were primarily temperature-dependent. Correlations were found between various flow cytometry-derived parameters and motility characteristics. Most of the correlations were obtained after a 24 h incubation in a capacitating medium. The most significant correlation in every experimental condition concerned the percentage of motile spermatozoa and the Rh123 uptakes. The drop in motility observed after a 24 h incubation was paralleled by a markedly lower drop in mitochondrial activity. The data suggest that these two complementary techniques represent an improvement in basic and/or clinical assessment of the functional spermatozoa status.

Flow Cytometry↗