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A Aanesen

Publications and source records attributed to A Aanesen.

15 recordsLinked to original sources
PubMed2004

Estrogen receptor beta is expressed in human embryonic brain cells and is regulated by 17beta-estradiol.

In order to study estrogen effects on developing human neurons, we have established primary cultures of neurons and glia from 8-13-week human embryo cortex and spinal cord. The neuronal identity of the cultures was verified using the neuronal synaptic vesicle and neuronal endosomal membrane markers synaptotagmin, synapsin and synaptophysin, and the glial contribution to the mixed glial-neuronal cultures was verified using the glial marker glial fibrillary acidic protein (GFAP). We here report expression of estrogen receptor beta (ERbeta) in these cells using RT-PCR and sequencing, RNAse protection assay, immunohistochemistry and immunoblotting. We found that both neuronal and mixed glial-neuronal cultures expressed ERbeta. Treatment with 17beta-estradiol gave an increased expression of ERbeta in both types of cultures. These results suggest that ERbeta is expressed in fetal brain and thus may mediate effects of estrogen in the developing nervous system. Furthermore, the results suggest that expression of ERbeta in fetal brain may be regulated by estrogen.

Calcium-Binding Proteins↗
PubMed2002

Delivery rates following IVF treatment, using two recombinant FSH preparations for ovarian stimulation.

BACKGROUND: A prospective, semi-randomized, open, clinical study was conducted to compare ovarian response, pregnancy outcome and delivery rates using two recombinant FSH preparations (Gonal-F and Puregon) for IVF. METHODS: We analysed stimulation parameters and outcome data in 812 initiated treatment cycles where 292 women used Gonal-F and 200 used Puregon. Embryo transfer was carried out in 676 cycles. In the two preparation groups we also compared 170 women previously treated with FSH for IVF with 266 previously untreated. RESULTS: The pregnancy rate with Gonal-F was 26% and with Puregon 28%. Delivery rates were identical, 22%. Clinical pregnancy and delivery rates per cycle with embryo transfer in earlier untreated women were 29.0 and 24.0%, whereas in previously treated women they were 23.5 and 18.8% respectively. After repeated cycles, delivery frequencies consecutively decreased, independent of the FSH preparation used. CONCLUSION: Gonal-F and Puregon seem to be equally potent in achieving follicular development and equally effective, in terms of delivery rates, for use in an IVF programme. Repeated cycles resulted in equally large consecutive decreases in delivery rates, regardless of preparation choice, but were considered worthwhile for up to three stimulation cycles in selected patients.

Adult↗
PubMed1999

[A male contraceptive injection can be available within 5 years].

After more than two decades of attempts to develop a safe male contraceptive, the goal now seems attainable. Spermatogenesis, which is dependent on endogenous testosterone production in the testes, may be controlled by such exogenous steroid hormones as testosterone, gestagens, or combinations of them. The recent development of gonadotrophin-releasing hormone (GnRH) antagonists has provided an added means of depressing testosterone production. Other targets for interference with male fertility are the germinal epithelium (e.g. using the cottonseed oil product, Gossypol, or Triptyrigeum Wilfordii extract), or the maturing sperm in the epididymis (using immunoactive substances).

Androgens↗
PubMed1998

Phorbol esters and synthetic diacylglycerols inhibit gamma-aminobutyric acid uptake in human spermatozoa: an effect mediated by protein kinase C?

Protein kinase C (PKC) and protein kinase A (PKA) are present in human spermatozoa and probably involved in the cascade systems leading to acrosomal exocytosis. We have investigated the possibility that these two protein kinases are involved in the regulation of gamma-aminobutyric acid (GABA) uptake in human spermatozoa. Swim-up preparations of human spermatozoa were exposed to phorbol 12-myristate 13 acetate (PMA) and 1-oleoyl-2-acetyl-sn-glycerol (OAG), which are activators of PKC, and to dibutyryl cyclic AMP (dbcAMP), a PKA activator, and subsequently incubated with radiolabelled GABA. Accumulated intracellular GABA was measured in a scintillation counter. Both PMA and OAG caused inhibition of GABA uptake while dbcAMP was without effect. The inhibitory effect on GABA uptake observed following exposure to the PKC activators could, however, not be counteracted by preincubation of the sperm samples with the PKC inhibitors staurosporine or H-7. The inhibitory effect on GABA uptake following addition of PMA was enhanced by prolonged exposure to the reagent and by increased capacitation prior to addition of the reagent. A small numerical increase in the percentage of acrosome-reacted cells was observed following exposure of the sperm cells to the highest concentrations of PMA, OAG and dbcAMP. No sperm motility parameters were affected by the treatment protocols as measured using computer-assisted semen analysis (CASA).

Diglycerides↗
PubMed1996

Progesterone stimulates GABA uptake in human spermatozoa.

Progesterone can initiate the mammalian sperm acrosome reaction in vitro, and studies on the effect of progesterone and several other steroids have demonstrated an increased calcium influx following binding to the sperm membrane. We have previously presented data indicating the presence of a GABA transport protein in human spermatozoa. In this study, we have examined the uptake of radiolabelled GABA into human spermatozoa in the presence of progesterone, other steroids known to elevate intracellular calcium, and steroids known to be ineffective as stimulators of calcium influx. The results demonstrate a twofold increase in GABA uptake following preincubation with progesterone or steroids known to stimulate calcium influx. Steroids with minor effects on calcium influx were less effective as stimulators of GABA uptake.

Biological Transport↗
PubMed1996

Bilateral tubal pregnancy following in vitro fertilization and transfer of two embryos.

A case of simultaneous bilateral tubal pregnancy after IVF-ET treatment is presented. This condition occurred despite the fact that only two embryos were transferred. Due to misinterpretation of repeated sonographic images, the diagnosis was delayed, and laparatomy with bilateral salpingectomy was not performed until 57 days had passed from the day of ET. Although there is a substantial risk of ectopic pregnancy following IVF-ET, this risk should be reduced as the number of embryos transferred per cycle decreases. This is, to the best of our knowledge, the first report of bilateral tubal pregnancies following the transfer of only two embryos.

Adult↗
PubMed1996

Carrier-mediated gamma-aminobutyric acid uptake in human spermatozoa indicating the presence of a high-affinity gamma-aminobutyric acid transport protein.

Human spermatozoa are capable of a carrier-mediated gamma-aminobutyric acid (GABA) uptake. The uptake is dependent on the concentration of Cl- and Na+ in the external medium, and the kinetics of the carrier resembles high-affinity GABA transport proteins. The time-dependent uptake of GABA displays large interindividual differences and is not correlated to motility parameters or morphology in the individual sample. Incubation of human spermatozoa with radiolabeled GABA was performed. Swim-up preparations of human spermatozoa were incubated with [3H]GABA, and subsequent GABA uptake was measured at various times by scintillation counting. GABA was accumulated intracellularly, and the uptake could be inhibited by preincubation of the samples in 200 microM nipecotic acid. Addition of aminooxyacetic acid in the medium did not alter the results, indicating that the internalized GABA remained unmetabolized intracellularly throughout the observation period. Kinetic analysis of GABA uptake was performed, and the Km for GABA transport was 14 microM. GABA uptake was reduced by equimolar substitution of NaCl in the capacitating medium by KCl, choline chloride, LiCl, N-methyl-D-glucamine (HCl) or D-glucuronic acid (sodium salt). Maximal reduction of [3H]GABA uptake was observed when the Na+ fraction of the medium was replaced with KCl. The results indicate the presence of a high-affinity GABA transport protein in the plasma membrane of human spermatozoa. GABA uptake was subsequently measured in 30 individual semen samples from men of barren couples. Large interindividual differences in GABA uptake was observed, but GABA uptake was not correlated to motility parameters or to morphology in the individual samples analyzed.

Carrier Proteins↗
PubMed1995

Evidence for gamma-aminobutyric acid specific binding sites on human spermatozoa.

The possible presence of gamma-aminobutyric acid (GABA) specific binding sites on human spermatozoa was investigated. Swim-up preparations of human spermatozoa were incubated with radiolabelled GABA in the presence of unlabelled GABA, alternatively displacers of GABAA/B receptors and GABA transport proteins. The results indicate that GABA specific binding sites are present on the surface of human spermatozoa, and that these binding sites possibly indicate the presence of GABA transport proteins. Furthermore, GABA at different concentrations was added to swim-up preparations of human spermatozoa. Possible effects of GABA on sperm motility, hyperactivation and acrosome reaction were explored. No significant differences were observed between treated groups and controls concerning motility parameters and hyperactivation. Incubation with GABA did not cause any increase in spontaneous acrosome reaction. However, spermatozoa treated with the calcium ionophore A-23187 showed a small but significantly increased ability to undergo the acrosome reaction following preincubation in 10(-4) M GABA (P < 0.05).

Acrosome↗
PubMed1990

Studies on requirements for trackpoints in CellSoft automated semen analysis.

The CellSoft (CRYO Resources, Ltd., New York, NY) system for computer-assisted sperm analysis was evaluated as to the appropriate settings for trackpoints. Fifty-eight human spermatozoa exhibiting complex swimming modes were chosen for analysis at room temperature. The accumulated measures for curvilinear velocity, linearity, mean and maximum amplitude of lateral head displacement, and beat cross frequency were determined over a range of trackpoints from 2 to 37. Stable measures (within the 95% confidence interval at 37 frames) were observed at 4 frames for curvilinear velocity and at 20 frames for linearity. The corresponding figure for mean amplitude of lateral head displacement and beat cross frequency was 8 frames. We conclude that the frame requirements concerning measures for curvilinear velocity/linearity and mean amplitude of lateral head displacement/beat cross frequency should be 20 and 8, respectively. Thus, 20 consecutive frames to analyze will suffice.

Computer Systems↗
PubMed1990

The CellSoft computerized semen analysis system: sperm image sizes and velocity measurements, and the consequences for internal running conditions.

The CellSoft computer-assisted sperm analysis system was evaluated as to the optimal setting of three components of the internal running conditions. These 'set up' parameters were the lower setting for cell size range (PIXMIN), threshold velocity (MINVEL) and maximum velocity (MAXVEL). The decision for the PIXMIN setting was founded on observed sizes of sperm with low instant velocities combined with a study of the relationship between false positive observations for sperm and the PIXMIN setting. Our recommendation for this setting is three pixels. From the observation that 97.5% of immobilized sperm exhibit instant velocities of less than 15 microns sec-1, this is our proposal for the MINVEL setting. Correspondingly, the 97.5 percentile for instantaneous velocities in a population of some 14,000 cells (30 men with type 'a' motility, WHO) was 168 microns sec-1. We recommend that MAXVEL be set at this limit. Alternative settings for both MINVEL and MAXVEL are presented as some users may wish to apply other percentiles. From the above results a setting for PIXMAX at 25 pixels could be inferred. We recommend that these settings be applied in semen laboratories analysing human native samples at room temperature.

Computers↗
PubMedDate not supplied

The CellSoft computerized semen analysis system. I. Consistency of measurements and stability of results in relation to sample size analyzed.

The CellSoft TM computer-assisted digital image analysis system was evaluated for reproducibility of measurements and for the sample size needed to obtain stable results for seven parameters characterizing human spermatozoa. The parameters were sperm density, velocity, linearity, percent motile cells, maximum and mean amplitude of sperm head's lateral displacement (ALH max and ALH mean) and beat cross frequency. Thirty men were assigned to three equally large groups according to sperm density, and the groups were studied separately. Consistency of measurements was highly acceptable for all parameters (coefficient of variation ranging from 0.9% to 3.7%). The average minimum number of sample size needed for stable results varied between the groups and within each group dependent upon the parameter studied. Velocity and linearity seemed to require the lowest average cell number, while percentage motile cells and ALH max needed the highest sample size. Our current recommendation of sample sizes is outlined in detail and limitations and future utility of CellSoft is discussed.

Evaluation Studies as Topic↗
PubMedDate not supplied

The CellSoft computerized semen analysis system. II. On the optimalization of running conditions concerning gray scale and cell size range.

The CellSoft automated semen analysis system was studied concerning the effect of gray scale (GSc) variation on cell motion parameters and to establish an appropriate setting for human spermatozoal sizes (PixMin and PixMax) based on the cell's instant velocities (InsVels). GSc could be set within a range from "optimum" till +10 units without, except for curvilinear velocity, the CellSoft generated sperm measures being altered (p greater than 0.05). The aspect of a sample specific GSc setting according to certain criteria is stressed. Considering the area of immobilized spermatozoa (at GSc + 20) and of motile cells with low InsVel, PixMin should be set at 3 pixels. Correspondingly, the InsVel determined setting for PixMax (at a maximum velocity threshold set at 200 microns/sec.) was 28 pixels. A final recommendation on the setting for cell sizes can, however, only be determined in considering sizes of nonsperm seminal elements and in studying the appropriate setting for the maximum velocity threshold.

Computer Systems↗