Biomedical subjects

B Rosenbusch

Publications and source records attributed to B Rosenbusch.

At least 37 records · Page 2Linked to original sources

PubMed1995

[Cytogenetic abnormalities in sperm: a risk factor for application of medical reproduction techniques?].

Microinsemination techniques are increasingly applied to achieve fertilisation of the oocyte in cases of male fertility disorders. Thus, spermatozoa can directly interact with the oolemma or the ooplasm, thereby obviating the need for penetration through cumulus oophorus and zona pellucida. However, problems associated with this particular feature arise in view of the following considerations: 1. The gametes from subfertile males are suspected to carry more cytogenetic anomalies in addition to an impaired sperm quality when compared to fertile men. 2. Cumulus and zona play an important role in the selection of morphologically abnormal and dysfunctional spermatozoa. 3. Consequently, bypassing natural sperm selection processes would lead to more abnormal embryos, abortions, and births of diseased or handicapped children. Spermatozoa can be analysed cytogenetically after fusion with zona-free hamster eggs or by fluorescence in situ hybridization (FISH). Both techniques did not confirm increased aberrations in gametes from subfertile men with a normal somatic karyotype. However, a definite conclusion cannot be drawn because of the limited data and restrictions concerning their interpretation. This also holds true for the evaluation of correlations indicating no significant relationship between the chromosomal constitution and sperm motility or morphology, respectively. Currently, the risk of malformation after microinsemination does not appear to be increased when compared to conventional IVF but the results do not yet allow a reliable statistical evaluation. In contrast, decreased morphological quality, impaired implantation, and early abortions have been reported for embryos produced by assisted fertilisation. This suggests that an effective natural selection of abnormal embryos will prevent a significant increase in malformations in the following generation.(ABSTRACT TRUNCATED AT 250 WORDS)

Chromosome Aberrations↗

PubMed1995

[Smoking--a possible cause for failure in IVF/ET treatment?].

The aim of this study was to investigate the relation between cigarette smoking of women and the fertilisation and pregnancy rates obtained by in-vitro fertilisation treatment. To guarantee an objective recording of tobacco smoke exposure, the smoking habit was not determined by questionnaires, but by cotinine, the principal metabolite of nicotine. The study population consisted of 197 women (23-39 years old) who were divided into the groups 'non-smokers' (n = 68), 'passive smokers' (n = 26) and 'active smokers' (n = 103) according to the cotinine concentration measured in follicular fluid. The reason for infertility was strictly a tubal factor with apparently normal ovulatory cycles. There were no significant differences in fertilisation and pregnancy rates between the different groups (p > 0.05). The E2 serum levels were significantly decreased in women who smoked, compared with the results obtained from non-smokers and passive smokers (p < 0.025). Overall, a strong negative correlation of the cotinine- and E2 levels was observed (r = -0.65). The results suggest that there is no clinically detectable impairment of fertilisation potential due to female smoking and that there is a greater influence on the outcome of in-vitro fertilisation by other factors.

Adult↗

PubMed1994

[The effect of different anesthetic procedures on hormone levels in women. Studies during an in vitro fertilization-embryo transfer (IVF-ET) program].

Different anaesthetic procedures that were used during an in vitro fertilisation and embryo transfer (IVF-ET) program have been analysed in order to determine their influence on plasma levels of estradiol, progesterone, prolactin, and beta-endorphin and results of IVF-ET. METHODS. Fifty-four patients awaiting transvaginal oocyte aspiration were randomised into three groups: (1) anaesthesia with ketamine as an induction agent and analgesic (n = 20); (2) general intubation anaesthesia using thiopentone for induction and enflurane for maintenance (n = 18); and (3) no anaesthesia (n = 16). Estradiol, progesterone, prolactin, and beta-endorphin were measured from day 3 to 14 referring to follicle aspiration. Differences between preoperative hormone levels and their intra- and postoperative peaks were analysed using the Kruskal-Wallis test (P < 0.03). The results were corrected using the Holms method (alpha = 0.05). RESULTS. No differences were observed in estradiol and progesterone levels (Figs. 1, 2). Prolactin levels were 1.4 times higher (P < 0.001) when ketamine was used and 2.2 times higher (P < 0.001) after short general anaesthesia than in the control group (Fig.3). Similar results were observed with respect to beta-endorphin: in comparison with the control group we found significant elevation by a factor of 2.1 when ketamine was used (P < 0.001). The discrepancy became even more marked with general anaesthesia: beta-endorphin was 3.9 times higher compared to the controls (P < 0.001) (Fig.4). Comparing the two groups who were given anaesthetics, prolactin and beta-endorphin levels were also significantly different (P < 0.001). The IVF procedure itself did not appear to be affected by different anaesthetic procedures during oocyte aspiration (Table 2). CONCLUSIONS. The increased prolactin and beta-endorphin plasma levels associated with ketamine and general anaesthesia reflect a significant alteration of the observed hormone levels. When anaesthesia is indicated, we try to avoid general intubation anaesthesia in favor of ketamine.

Adult↗

PubMed1994

In vitro kallikrein treatment of human spermatozoa: stimulation of sperm penetration into zona-free hamster eggs depends on the quality of initial semen parameters but not on constituents of the kallikrein-kinin system in seminal plasma.

We investigated the effect of an in vitro kallikrein treatment of human spermatozoa on their ability to penetrate zona-free hamster eggs. Sixty-four infertility patients were classified into four groups (normo-, oligo-, astheno-, and oligoasthenozoospermia) in order to find out which men would benefit most from this procedure. An aliquot of each ejaculate was diluted with Ham's F-10 medium supplemented with human serum albumin and kept at 22C for 1 hour. Another aliquot was incubated with kallikrein (5 KU/ml.) for one hour at 22C. These sperm suspensions were then washed twice, subjected to a swim-up preparation, and subsequently incubated at 37C for 2 hours. The mean penetration rates of kallikrein-treated samples were significantly higher than those of the corresponding control assays in all but the oligoasthenozoospermia group. Our results suggest a direct proteolytic action of kallikrein because the stimulation of penetration into hamster eggs was not correlated with the amount of constituents of the kallikrein-kinin system (kinins, kininogen, kininase) in seminal plasma.

Animals↗

PubMed1994

[Do preparation techniques induce ultrastructural sperm damage? An electron microscopic study].

We investigated the possibility of ultrastructural damage to human spermatozoa induced by different sperm preparation techniques. Ejaculates from 20 normozoospermic men were divided into equal aliquots and processed by glass wool filtration, Percoll density gradient centrifugation, and a simple two-step centrifugation procedure which served as a control. Ultrastructural damage was assessed by scanning electron microscopy. Compared with Percoll density gradient centrifugation, glass wool filtration yielded a significantly increased proportion of intact acrosomes (p < 0.05). However, both preparations gave significantly better results than control (p < 0.001 and p < 0.01 for glass wool filtration and Percoll centrifugation, respectively). The significance of the conspicuous bending of sperm tails after Percoll centrifugation is not yet known. In conclusion, both glass wool filtration and Percoll centrifugation are efficient techniques for the accumulation of spermatozoa with intact acrosomes. Because of the higher sperm recovery rate, glass wool filtration appears to be the more appropriate method.

Acrosome↗

PubMed1994

[Initial pregnancies after intravaginal transport and partial zona dissection of human ova].

We report on 72 couples with previous failure of fertilisation during several trials of conventional in-vitro fertilisation (IVF). In the present study part of the aspirated oocytes was subjected to partial zona dissection (PZD) before insemination, thereby achieving 7 pregnancies during 104 cycles. Normal in-vitro insemination of the remaining zona-intact oocytes was again unsuccessful. Since microinsemination techniques, in contrast to conventional IVF, are not yet being offered by many clinics, we developed the following new concept: hormonal stimulation, sonographic control of follicular growth, aspiration of oocytes, and sperm preparation were performed at the usual place (Munich) whereas PZD and control IVF were accomplished in another laboratory (Ulm). In order to transport the gametes between these two institutes, we modified the previously reported intravaginal culture (IVC) of inseminated oocytes by transferring oocytes and spermatozoa into separate plastic capsules. In our view, this procedure offers a suitable opportunity for infertile couples living too far away from a microinsemination centre to afford long daily journeys or even several overnight stays for superovulation treatment. The fertilisation and pregnancy rates in our study are comparable to those reported in the literature.

Adult↗

PubMed1994

[Effect of different follicle puncture methods on hormone homeostasis in the woman. Studies within the scope of an in vitro fertilization-embryo transfer program].

Different methods for follicular puncture which were used in an in vitro fertilization-embryo transfer program have been analyzed in order to determine their influence on plasma levels of estradiol, progesterone, prolactin and beta-endorphins. Thirty-eight patients awaiting oocyte aspiration were randomized into a laparoscopic (n = 20) and an ultrasound-guided oocyte aspiration group (n = 18). No differences were observed as far as estradiol and progesterone levels and embryo transfer rates were concerned. When using the laparoscopic technique, prolactin levels were found to be elevated 1.5 times in comparison with the ultrasound-guided aspiration procedure, which is highly significant (p < 0.001). Also, beta-endorphins peaked at a significantly higher level during laparoscopy (27.8 vs. 20.7 mol/l, p < 0.001). The enhanced prolactin and beta-endorphin levels reflect an increased stress response during laparoscopy. With respect to less trauma and shorter duration of the procedure, we now perform the sonographically guided transvaginal aspiration technique in our program almost exclusively.

Adult↗

PubMed1994

Cytogenetics of human spermatozoa. The frequency of various chromosome aberrations and their relationship to clinical and biological parameters.

Human sperm chromosomes can be visualized after their fusion with zona-free hamster eggs. We analyzed a total of 867 metaphases from 33 men that had been classified into three different groups. We present a detailed summary of the kind and frequency of chromosome aberrations we encountered. A comparison of our results with previous studies demonstrates considerable variations in numerical and structural chromosome anomalies in spermatozoa from normal, healthy men. The possible reasons for this are discussed. We reviewed some factors which are supposed to correlate with the occurrence of sperm chromosome aberrations; the effect of paternal age is still uncertain.

Adult↗

PubMed1993

Chromosomal analysis of unfertilized human oocytes prepared by a gradual fixation-air drying method.

Two hundred and sixty-five unfertilized human metaphase II (M II) oocytes from an in vitro fertilization program were studied cytogenetically using our chromosomal technique, a gradual fixation-air drying method. Of the 265 oocytes, 185 (70%) were successfully karyotyped. There were 21 aneuploids (11.4%) consisting of 8 hyperhaploids (4.3%), 11 hypohaploids (5.9%) and 2 complex cases (1.1%). There were also 9 structural anomalies (4.9%) and 18 diploids (9.7%). In aneuploidy, the loss or gain of dyads (so-called nondisjunction) occurred more frequently than the loss or gain of monads (so-called predivision). The frequency of abnormally behaved chromosomes (segregation errors) due to nondisjunction, anaphase lag and predivision was studied among the seven chromosomal groups (A-G) and compared with the frequency expected from an equal probability of segregation errors in each of the 23 chromosomes. The observed frequency was somewhat higher than the expected frequency in groups E and G but the difference was not statistically significant in either group. These results were discussed in relation to previous studies on human M II oocyte chromosomes.

Adult↗

PubMed1993

Scanning electron microscopy of human sperms after preparation of semen for in-vitro fertilization.

Ultrastructural changes of human sperms after routine preparation for in-vitro fertilization were examined by scanning electron microscopy. Studies were performed with freshly ejaculated semen of 21 normozoospermic patients. Spermatozoa were analysed at 10000-fold (sperm head with acrosome, postacrosomal border and postnuclear cap) and 2500-fold (midpiece and endpiece of sperm tail) magnification. Compared with untreated specimens, slight membrane damage was found after routine washing and centrifugation procedures in swim-up preparations. However, on the basis of a score system for quantification of morphologic data, no statistically significant differences existed between untreated semen and swim-up preparations. We conclude that, with normozoospermic semen, the rate of ultrastructural damage attributable to sperm-washing procedures is too low to be of clinical consequence.

Acrosome↗

PubMed1993

Tamoxifen treatment of oligozoospermia: a re-evaluation of its effects including additional sperm function tests.

Because of previous contradictory results, we reevaluated the effects of tamoxifen on 29 men presenting with idiopathic oligozoospermia. To determine whether a possible increase in sperm concentration might be correlated with an improvement of sperm quality, the hamster ovum penetration (HOP) test and the hypo-osmotic swelling (HOS) test were included as additional tests of sperm function. Patients were treated with tamoxifen (20 mg/day) for 3 months. From 4 weeks until the end of the study, tamoxifen had a significant effect (P < 0.001) on blood levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone (T), and estradiol (E2). Prolactin (PRL) concentrations were not altered significantly (P > 0.05). There was no significant improvement (P > 0.05) of conventional semen parameters (volume, concentration, motility, morphology), and of HOP and HOS test results. The lack of correlation between a rise in hormone levels and improvement of sperm quality suggests that tamoxifen is of questionable value in men with idiopathic oligozoospermia.

Adult↗

PubMed1993

First pregnancies after intravaginal transport and partial zona dissection of human oocytes.

We report on 72 couples with previous failure of fertilization during several trials of conventional IVF. For the present study, a part of the aspirated oocytes was subjected to partial zona dissection before insemination, thereby achieving 7 pregnancies during 104 cycles. Normal in vitro insemination of the remaining zona-intact oocytes was unsuccessful again. Because microinsemination techniques, in contrast to routine IVF, are not yet offered by many clinics, we developed the following new concept: hormonal stimulation, sonographic control of follicular growth, aspiration of oocytes, and sperm preparation were performed at the usual place (Munich), whereas partial zona dissection and control IVF were accomplished in another laboratory (Ulm). To transport the gametes between these two institutes, we modified the previously reported intravaginal culture of inseminated oocytes by transferring oocytes and spermatozoa into separate plastic capsules. In our view, this procedure offers an opportunity for infertile couples living too far away from a microinsemination center to afford long daily journeys or even several overnight stays just for superovulation treatment. The fertilization and PRs in our study are comparable with those reported in the literature.

Capsules↗

PubMed1993

[Cytogenetics of unfertilized or uncleaved oocytes within the scope of in vitro fertilization: correlation with maternal age].

A cytogenetic analysis could be performed on 343 out of 566 oocytes, which remained unfertilized or uncleaved during our IVF programme. The results were analysed with relation to the women's age by classifying the patients into two age groups (< or = 35 years and > 35 years). There was no significant difference for the corresponding total rates of abnormal oocytes (27.7% vs. 42.4%), the rates of aneuploidy (14.5% vs. 18.2%), and the rates of hyperhaploidy (4.8% vs. 3.0%). These results do not support the assumption of an increase in (numerically) abnormal gametes with increasing maternal age, which is of special interest in cases of trisomy 21. However, it is not possible to draw any definite conclusions, because of the low number of gametes, which were analysed in the upper age group.

Adult↗

PubMed1993

Concerted action of human chorionic gonadotropin and norepinephrine on intracellular-free calcium in human granulosa-lutein cells: evidence for the presence of a functional alpha-adrenergic receptor.

Luteal cells are known to possess receptors for LH/hCG and receptors of the beta-adrenergic type. Interactions of specific agonists with either receptor lead to the activation of adenylate cyclase and subsequently to an increase of cAMP. Since in the human there is also evidence for the presence of alpha-adrenergic receptors, we have investigated whether activation of these receptors is linked to calcium as a second messenger and performed measurement of intracellular free calcium (Ca2+) with Fura-2 in single human granulosa-lutein cells. Addition of either hCG (100, 1,000, 25,000 IU/L) or norepinephrine (NE; known to interact with both alpha- and beta-adrenergic receptors), beta-adrenergic receptor agonist isoproterenol (ISO), or alpha-adrenergic receptor agonist phenylephrine (PHE; all at 10 and 100 mumol/L) did not increase free intracellular Ca2+. However, the addition of combinations of NE/hCG, PHE/hCG, but not the combination ISO/hCG, induced a transient increase in cytosolic free Ca2+. The NE/hCG-evoked calcium signal was not abolished in the presence of the beta-adrenergic receptor antagonist propranolol and was not affected by removal of extracellular Ca2+. Furthermore, we tested whether catecholamines affected the release of progesterone in the presence or absence of hCG. As expected, hCG (10,000 IU/L) stimulated progesterone release by cultured granulosa-lutein cells. When these cells were incubated with NE, PHE, or ISO (at 10 mumol/L), production of progesterone by these cells was not affected. However, the combinations of NE and PHE with hCG abolished the hCG-induced progesterone accumulation, but ISO coincubated with hCG did not. Taken together, our results indicate: 1) the presence of functional alpha-adrenergic receptors on human granulosa-lutein cells; 2) simultaneous activation of two different receptors (for hCG and alpha-agonists) are able to evoke intracellular Ca2+ elevation, implicating postreceptor interactions in human granulosa lutein cells; 3) this process occurs even in the absence of extracellular Ca2+, indicating the involvement of intracellular Ca2+ stores, most likely due to activation of phosphoinositide pathway; 4) catecholamines most likely acting via alpha-adrenergic receptors, inhibit the LH/hCG-induced release of progesterone.

Calcium↗

PubMed1993

[Correlation between cytogenetic anomalies of human spermatozoa and sperm morphology as well as age of patients studied].

Sperm chromosomes from 15 fertile men were analyzed after fusion of their spermatozoa with zona-free hamster eggs. The total proportion of abnormal metaphases as well as the proportions of aneuploidy and structural aberrations were calculated for every man and examined for linear correlations with sperm morphology and the age of the persons studied. A positive correlation between the cytogenetic parameters and the percentage of abnormal sperm morphology was not evident, suggesting that assessment of sperm morphology cannot be used as an indicator of chromosomal damage in human spermatozoa. In contrast, there was a more distinct positive correlation between the age of donors and the three cytogenetic parameters studied. Analogous calculations for two other study groups (group S: male subfertility; group HA: habitual abortions of the wives with unknown etiology) provided less clear results that may be attributed to the lower number of patients or to the existence of special indications as mentioned above.

Abortion, Habitual↗

PubMed1993

[Cytogenetics of unfertilized or undivided oocytes within the scope of in vitro fertilization: relation to the kind of hormonal stimulation].

A cytogenetic analysis could be performed on 343 out of 566 oocytes which remained unfertilized or uncleaved during our in vitro fertilization (IVF) programme. The results were analyzed in relation to the kind of ovarian stimulation by classification of the patients into two groups: treatment with human menopausal gonadotropin (hMG) or treatment with clomiphene citrate (CC). There was no significant difference for the total rates of abnormal oocytes (hMG: 28.6%, CC: 32.2%), the rates of aneuploidy (hMG: 14.4%, CC: 16.9%), and the rates of hyperhaploidy (hMG: 3.9%, CC: 8.5%). These results suggest that the kind of medication for induction of multiple follicular growth does not influence the rate of cytogenetic anomalies in human oocytes.

Chromosome Aberrations↗

PubMed1992

Numerical chromosome anomalies after fertilization of freeze-thawed mouse oocytes.

The chromosome complement of first cleavage stage mouse embryos was analyzed to investigate the effect of slow freezing-fast thawing cryopreservation on chromosome numbers by comparing these numbers with those found fresh after fertilization of control oocytes. Fewer frozen-thawed (34.1%) than control oocytes (75.0%) cleaved to the 2-cell stage after in vitro fertilization. The incidence of hyperploidy was significantly increased by freezing (4.5% vs. 0% in controls). Polyploidy was not significantly affected (17.0% for freeze-thaw embryos vs. 26.2% for controls).

Aneuploidy↗

PubMed1992

Is there any correlation between follicular fluid hormone concentrations, fertilizability, and cytogenetic analysis of human oocytes recovered for in vitro fertilization?

Constituents of FF have been suspected to influence fertilizability and cytogenetic constitution of human oocytes. We therefore analyzed the FF concentrations of E2, P, T, and PRL for 114 oocytes recovered for IVF. Forty-six of these oocytes were fertilized and transferred to the maternal uterus. Among the unfertilized gametes, 27 were not analyzable, 30 were normal haploid, and 11 were classified as abnormal. There was no significant difference between fertilized and unfertilized oocytes for FF concentrations of E2, P, T, and PRL and for the E2:P ratios. Similarly, we detected no significant difference between normal and abnormal oocytes for these parameters.

Body Fluids↗