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Biomedical subjects

G Haidl

Publications and source records attributed to G Haidl.

At least 19 recordsLinked 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↗
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↗
PubMed1994

[The aging man from the andrologic viewpoint].

In view of demographic trends, andrology will increasingly be concerned with problems of the aging male. These will involve aspects of fertility and general quality of life rather than specific clinical pictures. While there is considerable interindividual variation, fertility in men usually persists well into old age. However, increased occurrence of spontaneous mutations means a higher genetic risk for children of older fathers. Diminished androgen levels in old age lead to diminished sexual activity and changes in muscles and bones, which raise the question of hormone substitution.

Aged↗
PubMed1994

[Pregnancy after drug therapy of severe andrological disorder].

Initial examination of an andrological patient revealed high-grade oligoasthenoteratozoospermia and ureaplasma infection. An elevated FSH level and significantly reduced testicular size were indicative of severely damaged testicular parenchyma. The presence of macrophages in the sperm smear was interpreted as a sign of chronic epididymitis. Antibiotic couple therapy with doxycycline, followed by a 3-month recovery period with combined treatment with vitamin C and E and zinc, resulted in a significantly improved spermiogram. After another 2 months intrauterine insemination resulted in pregnancy, and the birth of a healthy daughter followed. Preparation of the ejaculate was done by glasswool filtration. At that time, the patient had only mild teratozoospermia.

Adult↗
PubMed1994

When to treat varicocele?

In order to find criteria that might prognosticate the outcome of varicocele treatment, we studied 48 patients with unilateral or bilateral varicocele. Examinations prior to therapy included GnRH test and determination of alpha-glucosidase in addition to normal sperm analysis. The morphological analysis was performed according to the Düsseldorf classification. Thirty-five of the 48 patients underwent varicocele sclerosing, 13 patients received no therapy. Ten normozoospermic donors served as control. At 6-7 months after sclerosing, the aforementioned parameters were checked in all patients. Almost all of the untreated patients had pathological GnRH tests initially and on control, and sperm parameters had deteriorated. In the treated group, 75% had pathological GnRH tests initially. Of these, 70% improved, particularly sperm morphology with reduction of hyperelongated forms, and 30% had GnRH tests returned to normal. However, improved sperm parameters were also observed in 75% of patients who had normal GnRH tests initially. The improvement of sperm parameters was not associated with significant changes in alpha-glucosidase (normal initial values). According to these results, the GnRH test does not seem to be an important prognostic parameter for the outcome of varicocele therapy. However, patients with pathological values should be treated. Determination of alpha-glucosidase as an epididymal marker is no decisive criterion either. The most significant improvement was observed in patients with increased occurrence of hyperelongated spermatozoa.

Case-Control Studies↗
PubMed1993

Disturbances of sperm flagella due to failure of epididymal maturation and their possible relationship to phospholipids.

A recent classification of alterations of midpiece and flagellum describes the phenomenon of abnormal staining behaviour of human sperm flagella during Papanicolaou and Shorr staining. In these techniques, human sperm tails normally stain red; however, if epididymal function is disturbed, the flagella appear bluish, while they are devoid of other recognizable defects. Such spermatozoa were shown to be immotile, the motility disturbance being referred to as epididymal dysfunction. To define the physiological substrates of this descriptive phenomenon, caput spermatozoa from 10 epididymides of five patients who had undergone orchiectomy because of prostatic cancer were investigated. These spermatozoa showed severe motility disturbances, and almost all their flagella stained atypically. Attempts to stimulate such spermatozoa by pentoxifylline achieved a slight improvement in motility. However, addition of seminal plasma from fertile donors resulted in a significant improvement in motility, accompanied by an increase in the number of normally stained flagella. Even better results were achieved by incubation with liposomes made from soybean lipids, mainly phosphatidylcholine. It is concluded that poor motility and atypical staining behaviour of human caput sperm tails can at least partly be related to a lack of phospholipids in the flagellar membrane. Substitution of phospholipids may be a therapeutic approach in procedures using caput spermatozoa, although in addition to the improvement of sperm motility, the enhancement of fertilizing capacity remains to be established.

Aged↗