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G Haidl

Publications and source records attributed to G Haidl.

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

Sperm count in ejaculates and after sperm selection with discontinuous percoll gradient centrifugation technique, as a prognostic index of IVF outcome.

Success of IVF with low sperm count will depend on the retrieval of the maximum number of normal motile sperms, and this makes the selection of an appropriate technique critical. Various in vitro methods have been developed for selecting human sperm cells. Sperm selection using percoll gradient has been reported to yield upto 60% motile and morphologically normal spermatozoa from a normal semen sample. In this study, we have attempted to determine a possible relationship between sperm count in ejaculates before and after selection with percoll gradient centrifugation on one hand, and fertilization, cleavage and pregnancy rates in an IVF program on the other. With increased sperm count at the time of IVF treatment using selected sperm, we observed higher fertilization, cleavage and gestational rates. In conclusion, sperm concentration before and after selection with percoll may be considered a prognostic parameter for the determination of fertilization potential and pregnancy rates in an IVF program.

Cell Division↗
PubMed1997

[Testicular loss due to hemorrhagic infarct in Tauber antegrade scrotal varicocele sclerotherapy].

A 38-year-old patient with a grade 3 testicular varicocele was treated by antegrade scrotal sclerotherapy. Although performed technically accurate, antegrade sclerotherapy led to a haemorrhagic infarction of the testis by complete occlusion of venous drainage. The testis had to be removed. This complication has not been described yet and patients should be informed about this rare event.

Adult↗
PubMed1997

Inhibin B in men with normal and disturbed spermatogenesis.

Inhibin, a dimeric gonadal glycoprotein, inhibits the production and/or secretion of follicle stimulating hormone (FSH). The major species currently recognized are inhibin A (alphabeta A subunit) and inhibin B (alphabeta B subunit). In men, inhibin B seems to be the physiologically important form of inhibin. Therefore we measured serum inhibin B using a new two-site immunoenzymatic assay in 14 men (mean +/- SEM age, 34.5 +/- 0.7 years) with sperm counts >20 x 10(6)/ ml, in 35 men (mean +/- SEM age, 36.4 +/- 1.3 years) with oligozoospermia (sperm count <20 x 10(6)/ml) and in men with azoospermia (three orchidectomized men, three men with Klinefelter's syndrome, 10 men with Kallmann's syndrome). We compared inhibin B concentrations with serum FSH and sperm concentrations. In men with normal sperm concentrations (44.7 +/- 6.4 x 10(6)/ml), the concentration of inhibin was 223 +/- 18 pg/ml and of FSH 5.0 +/- 0.7 IU/l; in patients with low sperm concentrations (3.7 +/- 0.8 x 10(6)/ml), the concentration of inhibin B was 107 +/- 12 pg/ml and of FSH 12.2 +/- 1.5 IU/l. In all patients, except those with hypogonadotrophic hypogonadism, the relationship between inhibin B and FSH concentrations was inverse (r = -0.69, P < 0.0001). In all patients the sperm concentration was positively correlated with inhibin B concentrations (r = 0.70, P < 0.0001) and negatively correlated with FSH concentrations (r = -0.37, P < 0.01). We conclude that inhibin B may be a marker of exocrine testicular function and could offer improved diagnosis and treatment modalities for male infertility.

Adult↗
PubMed1997

Success of intracytoplasmic sperm injection in couples with male and/or female chromosome aberrations.

This paper reports on results of intracytoplasmic sperm injection (ICSI) in patients in whom constitutional or secondary chromosome aberrations were detected in the male and/or female partner. Out of 434 couples treated by ICSI (590 cycles), 16 couples (3.7%) were affected by constitutional chromosome aberrations and 96 (22.1%) by secondary chromosome aberrations. Constitutional chromosome aberrations were found in eight male and eight female patients. Couples with the aberration in the male showed significantly lower fertilization, implantation and pregnancy rates (P < 0.05). The occurrence of female constitutional chromosome aberrations led to lower fertilization rates but implantation and pregnancy rates were similar to a control group; however, a higher abortion rate was noted. In the group with secondary chromosome aberrations, 22 males and 59 females carried an abnormality and in 15 couples, both partners. Compared to the remaining (unaffected) 322 couples, fertilization and embryo transfer rates were reduced but implantation rates and pregnancy rates were not different. In all couples where an abortion occurred, mainly parental autosomal aberrations were involved (six out of eight). Our retrospective analysis shows that an unexpectedly high number of infertile couples in an ICSI programme are affected by chromosome aberrations, which in turn may explain the reduced fertilization rates observed in this subgroup of patients.

Abortion, Spontaneous↗
PubMed1997

Changes in lipids and membrane anisotropy in human spermatozoa during epididymal maturation.

Previously it was demonstrated that immature and immotile human spermatozoa from the caput epididymides developed a good progressive motility after in-vitro stimulation with phosphatidylcholine (PC). In order to define the role of PC and membrane anisotropy in epididymal maturation and to determine the exact lipid composition of human spermatozoa during epididymal maturation, spermatozoa from seven epididymides from patients who underwent orchiectomy because of prostatic cancer were investigated. Lipids were determined by high-performance thin-layer chromatography and gas chromatography. Membrane anisotropy was measured by fluorescence polarization. The ratio between PC and phosphatidylserine (PS) plus phosphatidyl ethanolamine (PE) plus sphingomyelin (SM) was significantly higher in spermatozoa from the cauda compared to those from the caput and corpus. This was due to an increase of PC and a decrease of the concentration of PS plus PE plus SM. With regard to fatty acids, those with saturated chains predominated in caput spermatozoa while the highest concentration of unsaturated long-chain fatty acids was in cauda spermatozoa. A lower membrane anisotropy of cauda spermatozoa compared with caput or corpus spermatozoa was found. In conclusion, during epididymal maturation human spermatozoa integrate lipids, particularly PC, which is strongly associated with the induction of progressive motility. A change in the pattern of fatty acids and a decrease in the cholesterol/phospholipid molar ratio cause a decrease in membrane anisotropy in cauda spermatozoa.

Aged↗
PubMed1997

Combined cytogenetic and Y chromosome microdeletion screening in males undergoing intracytoplasmic sperm injection.

We evaluated the frequency of chromosomal aberrations and microdeletions of the Y chromosome in a sample of 204 patients included in an intracytoplasmic sperm injection (ICSI) programme. The prevalence of Y chromosome deletions in males with severely or only moderately reduced sparm counts is mainly unknown, so that patients were chosen with sperm counts ranging from mild oligozoospermia to azoospermia. While six out of 158 (3.8%) patients showed constitutional chromosomal aberrations, only two out of 204 (0.98%) patients were diagnosed with a microdeletion of Yq11. One had a terminal deletion in subinterval 6 of Yq11.23 which included the DAZ gene and a corresponding sperm count < 0.1 x 10(6) spermatozoa/ml. The second patient had an isolated deletion of marker Y6PH54c, a more proximal site in subinterval 5 on Yq11.23, but repeatedly showed sperm counts of 3-8 x 10(8) spermatozoa/ml. Thus, of the 158 patients who underwent a combined cytogenetic and Y-microdeletion screening, eight patients (5.1%) showed chromosomal abnormalities, either at the cytogenatic (n = 6) or the molecular level (n = 2). In conclusion, although rare in number, microdeletions of the Y chromosome can also be observed in patients with moderately reduced sperm counts. A more proximal site of the deletion breakpoint does not necessarily imply a more severe impairment of spermatogenesis than a distal deletion site. In our sample, the overall frequency of constitutional chromosomal aberrations exceeded the incidence of microdeletions of the Y chromosome even in patients with idiopathic azoo- or severe oligozoospermia.

Chromosome Deletion↗
PubMed1996

[Andrologic diagnosis today].

For the diagnosis of male fertility disorders, history-taking, physical examination and the semen analysis continue to be the main pillars of the initial investigative program. The physical examination frequently includes rectal and testicular ultrasonography. For the most part, considerable importance is attached to the accurate examination of sperm morphology. Additional investigations are, however, often required. Of importance here is a careful work-up of any inflammation presenting, the determination of spermatozoa antibodies, and a basic investigation of the hormones. Sperm function tests are increasingly being performed, the most important of which are acrosine activity, the acrosome reaction, chromatin condensation, and spermovum binding. The biochemical determination of specific marker enzymes, testicular biopsy and a detailed microbiological work-up round off the diagnostic program.

Diagnosis, Differential↗
PubMed1996

Human Y chromosome azoospermia factors (AZF) mapped to different subregions in Yq11.

In a large collaborative screening project, 370 men with idiopathic azoospermia or severe oligozoospermia were analysed for deletions of 76 DNA loci in Yq11. In 12 individuals, we observed de novo microdeletions involving several DNA loci, while an additional patient had an inherited deletion. They were mapped to three different subregions in Yq11. One subregion coincides to the AZF region defined recently in distal Yq11. The second and third subregion were mapped proximal to it, in proximal and middle Yq11, respectively. The different deletions observed were not overlapping but the extension of the deleted Y DNA in each subregion was similar in each patient analysed. In testis tissue sections, disruption of spermatogenesis was shown to be at the same phase when the microdeletion occurred in the same Yq11 subregion but at a different phase when the microdeletion occurred in a different Yq11 subregion. Therefore, we propose the presence of not one but three spermatogenesis loci in Yq11 and that each locus is active during a different phase of male germ cell development. As the most severe phenotype after deletion of each locus is azoospermia, we designated them as: AZFa, AZFb and AZFc. Their probable phase of function in human spermatogenesis and candidate genes involved will be discussed.

Chromosome Mapping↗
PubMed1996

Ageing and sperm function.

To evaluate the fertilizing capacity of spermatozoa from elderly men, ejaculates from 29 older fathers (mean age 50.3 years) were compared with those from 35 younger fathers (mean age 32.2 years). In addition to conventional semen parameters, sperm functions were studied that have been reported to be positively correlated with the fertilization rate: progressive motility, acrosin activity, inducible acrosome reaction, and chromosome condensation. Sperm concentration and follicle stimulating hormone concentration differed significantly in both groups. With regard to sperm functions there were no differences between older men and younger men, except for decreased sperm motility in the older group which, however, reached nearly normal values according to World Health Organization criteria. Decreased fertility of older couples is obviously more dependent on the age of the female partner. The significance of genetic risks remains to be clarified, especially when methods of assisted reproduction are applied.

Acrosin↗
PubMed1996

Analysis of intra-operative aspirates taken during microsurgical refertilization in obstructive azoospermia--preliminary results. The BMFT Study Group for Microsurgery, Giessen.

The reasons for the discrepancy between 'patency' and 'pregnancy' in the outcome of microsurgical refertilization are partially unknown. The quality of the intra-operative aspirate and of the spermatozoa at the level of the anastomosis are discussed worldwide as important factors influencing the success of fertilization in the case of post-operative patency. In 152 men undergoing microsurgical refertilization (vasovasostomy, tubulovasostomy, microsurgical epididymal sperm aspiration, transurethral resection of the ejaculatory duct), 281 aspirates were classified intra-operatively according to Silber, and post-operatively using the Shorr staining technique. In 62 aspirates a computer-aided sperm analysis (CASA) was performed. The percentage of intact spermatozoa decreased from 94.9% at the caput to 9.4% at the cauda epididymidis. The post-operative classification demonstrated an acceptable correlation (0.71) to all grades of intraoperative classification. There was a good correspondence in Silber 4 and 5 but worse in Silber 1 and 2. In CASA, the percentage of motile spermatozoa was not different between epididymal and post-epididymal aspirates. Furthermore, velocity parameters did not differ significantly, but there was a significantly higher straightness of post-epididymal spermatozoa in comparison to epididymal spermatozoa.

Adult↗
PubMed1995

Microsurgical aspects of the treatment of azoospermia. The BMFT Study Group for Microsurgery.

Technical advances in microsurgery have produced a calculable success rate for reconstructive surgery in cases of obstructive azoospermia. Nevertheless, in standardized vasovasostomy and tubulovasostomy, the different outcomes for patency and pregnancy indicate that further comprehensive clinical and basic scientific studies are required to improve the results of surgery. The aspiration of epididymal and testicular spermatozoa in combination with intra-cytoplasmic sperm injection (ICSI) is one example of a fruitful integration of microsurgery into new areas of reproductive medicine. Where there is ejaculatory duct obstruction, the continuity with the posterior urethra can be restored by a transurethral operation.

Humans↗
PubMed1994

[Asthenozoospermia--a multifactorial symptom].

For the clarification of sperm motility disorders, changes in the flagella must be differentiated from influences exerted by the seminal fluid and extrinsic factors. The disorders of the flagella may be testicular or epididymal in origin. Only by taking account of these aspects of etiology and pathogenesis, will a rational therapeutic approach be possible.

Ciliary Motility Disorders↗
PubMed1994

[Epididymal maturation of human spermatozoa].

The role of the human epididymis in spermatozoa maturation is demonstrated by means of several sperm function tests, with the aid of which, the various stages in the fertilization process can be mimicked. Accordingly, as they pass through the epididymis, spermatozoa become progressively more motile--which can be enhanced by the addition of phosphatidylcholine--inducibility of the acrosome reaction increases, and chromatin condensation is completed. Capability of fusing with the ovum is observed for spermatozoa from the epididymis, but not for those from the caput epididymis, while the spermatozoa from the latter already have normal acrosine activity. Ability to bind to the zona pellucida has not been adequately clarified. These results demonstrate the significance of the human epididymis for sperm maturation, even though a small percentage seem to reach adequate maturity in the caput epididymis.

Epididymis↗
PubMed1994

New aspects of the aetiology of male fertility disorders.

Classification of male fertility disorders should take into account the cause and severity of a disturbance as well as its effect on the fertilizing capacity of spermatozoa. A reasonable approach is the analysis of sperm morphology according to the Düsseldorf classification, which is based on defects of spermatid differentiation. The kind and frequency of malformed spermatozoa allow conclusions about basic testicular and epididymal disorders, which will facilitate the detection of epididymal sperm motility disturbances and, therefore, initiation of causal treatment. The effect of inflammatory processes on fertility depends on the site of inflammation. In addition, the necessity for varicocele treatment can be determined more exactly under consideration of sperm morphology and hormonal tests. So far, irregular chromatin condensation as a cause of disturbed male fertility has not been attributed to genetic reasons, whereas microdeletions of the Y chromosome are increasingly being discussed. Both the role of oxygen radicals and the significance of environmental factors need to be investigated in the future.

Adult↗