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K Sterzik

Publications and source records attributed to K Sterzik.

At least 37 records · Page 2Linked to original sources
PubMed1997

The effect of follicle stimulating hormone therapy on human sperm structure (Notulae seminologicae 11).

The effects of follicle stimulating hormone (FSH) treatment on the quality of human spermatozoa were assessed by examining the ultrastructure and the function of infertile human spermatozoa using a previously-defined formula. Using the spermatozoa as an andrological monitor shows that the therapeutic effect of FSH depends on the type of sperm defect. The response to FSH is, in many cases, positive and can be evaluated by examining the state of the ejaculated spermatozoa. From an initial group of 81 patients, 15 were placebo-treated controls, and 19 were non-responders (mainly with microbially infected semen). Out of 47 responders, after therapy nine achieved improved sperm quality which approached the natural fertility threshold. These responders all had spermatozoa affected by immaturity or apoptosis (n = 27). The 20 microbially-infected responders also had immature spermatozoa and never achieved the quality level of natural fertility. Thus, a natural fertility level was only achieved by nine responders out of 27 (three with immature spermatozoa, and six with apoptotic spermatozoa). Using our method of sperm analysis, these patients' spermatozoa were clearly categorized before treatment as either immature or apoptotic. In consequence, the success of the therapy was predictable. The response of individual organelles to therapy was examined. Certain qualities of the acrosome, the chromatin, the mitochondria, and the axoneme appear to be sensitive to FSH. Most of the previous conflicting results reported in the literature may be due to a lack of relevant discrimination between the different defects present in the spermatozoa of the patients, without assessing the likelihood of their response.

Acrosome↗
PubMed1997

Submicroscopic mathematical evaluation of spermatozoa in assisted reproduction. 3. Partial zona dissection (PZD) (Notulae seminologicae 12).

This paper belongs to a series of application of the Baccetti's et al. (1995) formula to the submicroscopical mathematical examination of the human spermatozoa used for assisted reproduction. The present experiment concerns partial zona dissection, a technique requiring a careful evaluation of sperm quality in order to predict the success of the program. Our results demonstrate that the sperm submicroscopic characters introduced in the formula are clearly correlated with the result of PZD. In fact the two numbers concerning the sperm ultrastructural quality (percentage and total number of spermatozoa free from defects in the ejaculate) obtained in successful and unsuccessful PZD groups, showed a large difference (P < 0.01). The most important characteristics seem to be the quality of the acrosomal complex, the condition of the chromatin and the mitochondrial assembly. All these characteristics are expressed with largely different means in successful and unsuccessful ejaculates (from P < 0.05 to P < 0.01). A comparison with the results previously obtained in ICSI (Strehler et al., 1995) and IVF (Piomboni et al., 1996) shows that sperm quality is significantly more implicated in the success of IVF than of PZD or ICSI.

Female↗
PubMed1996

Submicroscopic mathematical evaluation of spermatozoa in assisted reproduction. 2. In vitro fertilization. (Notulae seminologicae. 7)

This paper belongs to a series of applications of the Baccetti et al. formula (1) to the submicroscopical mathematical examination of human spermatozoa used for assisted reproduction. The present experiment concerns IVF, a technique requiring careful evaluation of sperm quality to predict the success of the program. Our results demonstrate that the sperm submicroscopic characters introduced in the formula are clearly correlated with the result of IVF. In fact the two numbers concerning sperm quality (percentage of spermatozoa free from structural defects and total number in the ejaculate of spermatozoa free from defects) obtained in successful and unsuccessful IVF groups, showed a large difference. The t distribution in both cases reached a significance of 0.005. The synthetic parameters obtained are therefore a good tool in the prediction of sperm power in in vitro insemination techniques. The most important characteristics seem to be the quality of the acrosomal complex, the status of the chromatin, the shape of mitochondria, the axonemal pattern, and the membrane integrity. All these characteristics are expressed with largely different means in successful and unsuccessful ejaculates (t distribution significant at 0.005). All these data confirm that submicroscopic mathematical diagnosis offers a convincing evaluation of sperm structure and function, involving all organelles, including acrosome function and cell motility. It is also demonstrated that sperm quality is a major factor in the success of IVF and that it is clearly revealed by the integrity of the majority of the sperm organelles.

Acrosome↗
PubMed1996

Influence of smoking on fertility in women attending an in vitro fertilization program.

OBJECTIVE: To investigate the influence of cigarette smoking of women on the fertilization and pregnancy rates obtained by IVF treatment. PATIENTS: One hundred ninety-seven infertile, otherwise healthy women who entered an IVF program for the first time. SETTING: Fertility unit at the Women's University hospital of the University of Ulm, Ulm, Germany. INTERVENTIONS: The study population consisted of 197 women (23 to 39 years old) who were divided into the following groups: nonsmokers (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. 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. RESULTS: There were no significant differences in fertilization and pregnancy rates between the different groups. The E2 serum levels were decreased significantly in women who smoked when compared with the results obtained from nonsmokers and passive smokers. Overall, a strong negative correlation of the cotinine and E2 levels was observed (r = -0.65). CONCLUSION: The results suggest that there is no clinically detectable impairment of fertilization potential due to female smoking and that there is a greater influence on the outcome of IVF by other factors.

Adult↗
PubMed1996

Beyond recanalizing proximal tube occlusion: the argument for further diagnosis and classification.

Proximal tube occlusion (PTO) accounts for 20% of tubal factor cases. The classification into nodular (salpingitis isthmica nodosa or endometriosis), non-nodular (true fibrotic occlusion) and so-called pseudo occlusion (detritus, polyps, hypoplastic tubes) is essential. Using falloposcopy, PTO that is already diagnosed by laparoscopy and hysterosalpingography (HSG) can be confirmed or bypassed (false PTO); patients with false PTO were placed on a temporary waiting period. Nodular and pseudo occlusion patients were pre-treated with gonadotrophin-releasing hormone analogue (GnRH-a) for at least 6 weeks to shrink the underlying pathology, after which tubal re-catheterization was performed. In a prospective study starting in July 1993, 53 patients prediagnosed as having PTO were examined by falloposcopy. Three of these patients had non-nodular occlusion and were directed to microsurgical repair (conservative treatment not possible). A total of 19 cases revealed patent tubes with healthy mucosa and no underlying pathology (false PTO). Of the remaining 31 patients, 18 were classified as nodular and 13 as pseudo occlusion. In all of these patients at least one tube was patent after GnRH-a treatment. After a 6 month period, 37% of the false PTO patients achieved a spontaneous pregnancy (6% per cycle). The spontaneous pregnancy rate in the true PTO group was significantly lower (10% per patient, 1.6% per month; P < 0.05). Using assisted reproduction techniques, in particular gamete intra-Fallopian transfer (GIFT), as a subsequent treatment for the true PTO group, a pregnancy rate of 50% per cycle was achieved. A retrospective analysis of our entire PTO population (n = 109) showed a spontaneous pregnancy rate after achieving tubal patency (using falloposcopy and GnRH-a) that was dramatically low (1.8%), with no difference between the nodular and pseudo groups. The chance for pregnancy can be enhanced significantly (P < 0.001) using assisted reproduction techniques (GIFT) following tubal re-catheterization and GnRH-a treatment.

Buserelin↗
PubMed1995

Predicting the success of in vitro fertilization: conventional semen analysis compared to the hamster ova penetration test.

In vitro fertilization has been advocated as a possible treatment for male factor infertility. Using data collected on 154 men, conventional semen analysis and the hamster ova penetration test are compared with respect to their power in predicting the success of assisted conception. As performing the hamster test is more expensive than the semen analysis, we also investigate a combined strategy. It performs better than the discrimination based solely on the semen parameters, but does not lead to an improvement over the overall discriminatory power obtained from the hamster test alone.

Adult↗
PubMed1995

[Idiopathic habitual abortion: experiences with active immunotherapy].

The effect of lymphocyte transfusions on the stabilisation and successful outcome of pregnancy was investigated in 30 women with recurrent abortions presumably caused by immunologic factors. Lymphocyte concentrates were obtained from stored whole blood of the husbands and transferred by intravenous injection. Exclusion criteria for this study were the presence of antipaternal lymphocytotoxic antibodies in the patient's serum (cross match) or an advanced pregnancy (> 12 weeks). After transfusion of paternal lymphocytes 19 (63%) women had uncomplicated and successful pregnancies whereas 11 (37%) suffered again from early pregnancy loss. Two out of these 11 patients aborted twice. The probability of a successful treatment decreased as soon as lymphocytotoxic antibodies appeared in the patient's serum (p < or = 0.021). Women with a lower number of abortions before treatment carried their pregnancies to full term more frequently (p < or = 0.03). The number of transfusions, the period between start of treatment and conception as well as the distribution of age within the two groups had no significant effect on the outcome of therapy. A lack of lymphocytotoxic antibodies or their late appearance during treatment give a positive prognosis for the progress of pregnancy. Compared with a fertile control group, couples with habitual abortions showed no significantly increased HLA sharing. Immunisation with paternal lymphocytes in cases of presumably habitual abortions due to immunologic factors appears as an effective therapy with only few side effects. Large, randomised, double-blind, and placebo-controlled trials are needed before drawing conclusions.

Abortion, Habitual↗
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↗
PubMed1995

Relaxin triggers calcium transients in human granulosa-lutein cells.

Although the peptide hormone relaxin is synthesized by the human corpus luteum in vivo, its potential to serve as a local factor in the regulation of luteal function is not clear. Using an enzyme-linked immunosorbent assay for human relaxin, we detected relaxin in the culture medium of human granulosa-lutein cells as early as after 6 days in culture. Moreover, 1 x 10(5) IU/l human chorionic gonadotropin stimulated relaxin release about fourfold during a 48-h incubation on culture days 6-8 (and 7-9), but not earlier (on days 1, 3 and 4). The stimulatory action of human chorionic gonadotropin on progesterone release was not influenced by relaxin, and relaxin alone was without stimulatory effect. However, human recombinant relaxin (between 0.1 and 12.5 micrograms/l) increased intracellular free Ca2+ basal levels to maximal peak levels exceeding 1000 nmol/l in about 64% of all tested cells (N = 168) with no obvious dependency on the culture day. The relaxin-induced Ca2+ signal was not affected by removal of extracellular Ca2+. As depletion of intracellular Ca2+ stores by ionomycin rendered the cells unresponsive to relaxin or diminished their ability to respond, these results point to an intracellular source of the Ca2+ signal. In summary, our data indicate the presence of a functional relaxin receptor on human granulosa-lutein cells, which is linked to Ca2+ release from intracellular stores.

Calcium↗
PubMed1995

[Electron microscopic analysis of possible ultrastructural damage to spermatozoa after preparation by various methods].

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 conspicuous bending of sperm tails after Percoll centrifugation has a yet unknown importance. 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

Hormone regulation and hormone antagonist effects on protein patterns of human endometrial secretion during receptivity.

Endometrial receptivity is a particular stage of maturation during the luteal phase to permit implantation. We have studied endometrial protein secretion and its patterns evaluated by SDS-PAGE, laser densitometry and Western blots. Uterine secretion electrophoresis (USE) permits highly sophisticated analyses of the intrauterine milieu and allows clinical determination of the receptive stage of the endometrium. This technique reveals direct parameters by patterns of numerous individual protein bands, mainly resolved between 68.0 and 6.5 kD. Characteristic bands appear during the typical functional states of the menstrual cycle presenting evidence on the diagnostic capacity of this method to identify stages of adequate (= normal) or inadequate (= defective) luteal phase maturation. Several individual protein bands appear as characteristic markers for the receptive stage of the luteal phase. We have isolated and molecularly identified several of these proteins: histones H2A, H2B, H3 and H4. In order to identify the endocrine dependency of the protein bands, which significantly contribute to the "receptive stage pattern," patients were treated with the progesterone antagonist RU 486 at day LH +2. The assessment 4 days later revealed deficient USE patterns, particularly diminished and missing bands of the H2A-, H2B-, and H3-histones. These results demonstrate progesterone-dependent components of the endometrium at the receptive stage, which can be used as useful markers for an improved precision in luteal phase diagnostics. On the other hand, essential parts of the protein pattern may serve as new targets for successful contraceptive interventions ("endometrial contraception").

Animals↗
PubMed1994

Expression and alternative splicing of the neural cell adhesion molecule NCAM in human granulosa cells during luteinization.

Freshly aspirated human granulosa cells from pre-ovulatory follicles and granulosa cells luteinized in culture possess the neural cell adhesion molecule (NCAM) of approximate molecular mass of 140,000 and NCAM mRNA as confirmed by S1-nuclease protection assays and RT-PCR. Moreover, in the process of luteinization the NCAM isoform pattern is modified. Isoforms containing an insert of 10 amino acids (termed VASE) in the extracellular domain of NCAM were supplemented by alternatively spliced isoforms without this insert. NCAM immunoreactivity, at light and electron microscope levels, was associated with the cell membrane of most granulosa cells which formed clusters. During time in culture an increasing subpopulation of granulosa cells, devoid of NCAM immunoreactivity, spread out and formed monolayers. This differential expression and the alternative splicing of NCAM during luteinization of granulosa cells raise the possibility that NCAM could be involved in folliculogenesis and the formation of the corpus luteum in the human.

Alternative Splicing↗
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↗