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Biomedical subjects

B Fredricsson

Publications and source records attributed to B Fredricsson.

65 records · Page 4Linked to original sources
PubMedDate not supplied

Steroid metabolism and morphologic features of the human testis.

Serum FSH, LH, and testosterone were studied in 114 infertile men with poor sperm production. Testicular biopsies were taken and classified morphologically. In 90 specimens, the pattern of conversion of progesterone was determined in vitro and expressed as the ratio of 20 alpha-hydroxy-4-pregnene-3-one to 17 alpha-hydroxyprogesterone. An excess of the former metabolite indicates a prepubertal type of steroid metabolism. The normal limit of this ratio is given. The collected data indicate that the prepubertal type of steroid metabolic pattern is related to the thickness of the lamina propria of the seminiferous tubules only, and not to peripheral hormone levels. In particular, the presence of hyaline deposits in the lamina propria seems to determine the metabolic pattern. It is suggested that the character of the lamina propria separating the tubular and interstitial compartments of the testis is of crucial importance for the functional interrelationship between these compartments. This supports the concept of an intratesticular regulatory mechanism of both steroid metabolism and spermatogenesis.

Adult↗
PubMedDate not supplied

On the development of different morphologic abnormalities of human spermatozoa.

morphologic comparisons of the live and dead sperm population gives information concerning non-lethal and lethal abnormalities. Many of the abnormalities of the sperm heads and midpieces and in particular enlarged heads belong to the latter group. On the other hand, tapering of the head, cytoplasmic droplets and abnormal tails have littel lethal significance. Depletion of the extra-gonadal sperm reserve does not affect the morphology of neither the living nor the dead spermatozoa. This indicates that no significant abnormalities develop after sperm maturation within the epididymis. Cyproterone acetate was shown to affect midpieces and fails of the living spermatozoa within two weeks of treatment indicating an effect on the epididymal level, whereas abnormal heads increase after four weeks indicating an effect on the germinative epithelium, not before the spermatid stage.

Adult↗
PubMedDate not supplied

Vitality and morphology of human spermatozoa. Studies on the resistance to storage and centrifugation and on the removal of dead spermatozoa.

The effect of storage of human spermatozoa at room temperature and in the refrigerator was studied. Loss of vitality was found to be linear and the same within the temperature range studied. Vitality was reduced by 0,9% per hour on average. The rate of this loss did not show much variation. The morphology of both all spermatozoa and the living sperm population studied separately was only slightly impaired by storage. The effect of centrifugation and resuspension of spermatozoa was studied separately. Vitality was found to be reduced by gravitation forces of 800 g for 20 minutes whereas no effect on morphology was noted by this treatment. Gravitation forces of 600 g and below did not significantly affect the spermatozoa. Two methods of separation of spermatozoa with better motility and morphology from the rest of the semen sample were studied, (1) filtration through a layer of glass beads, (2) "sperm rise" after centrifugation at low gravitation force. The clinical value of these procedures is probably limited to selected cases.

Cell Separation↗
PubMedDate not supplied

Effects of low doses of cyproterone acetate on sperm morphology and some other parameters of reproduction in normal men.

Cyproterone acetate was given to three healthy men in a dosage of 10 mg per day for 8-14 weeks. The effects on sperm count, morphology, motility and vitality was followed weekly and compared with the effects of 25 mg daily in another case. Sperm morphology included the study of live spermatozoa separately. The effects on serum levels of FSH, LH, testosterone and oestrogens was also studied. With respect to sperm count and morphology a dose-effect relationship is indicated. Abnormalities within tails and midpieces of live spermatozoa appear early and may predict sterility before azoospermia develops. FSH and oestrogens were comparatively more depressed than LH and testosterone. The results indicate that cyproterone acetate may have an androgenic (or gestagenic) effect on the hypophyseo-hypothalamic level in addition to an antiandrogenic effect on gonads and their accessory organs.

Adult↗
PubMedDate not supplied

Infertility caused by antispermatozoal antibodies in the male experience from an intermittent high dose cortisone regimen.

Seventeen infertile male patients with antispermatozoal antibodies in seminal plasma and/or serum were treated with methylprednisolone, 48-96 mg daily for one week every other month in synchrony with the partner's menstrual cycles. Three to six treatment courses were given. One patient with draw from further treatment because of mental disturbance during the first cycle. Seminal plasma titres were affected more than titres in serum by the treatment. In the 16 couples completing treatment at least one pregnancy was achieved in six. Children were born to five of them. The observed pregnancy rate is similar to that previously reported. Risks of the treatment and safety precautions are discussed.

Adult↗
PubMedDate not supplied

Morphology of seminal and swim-up spermatozoa and the outcome of in vitro fertilization and embryo transfer.

Tubal infertility was treated by in vitro fertilization-embryo transfer (IVF-ET) in 112 couples. Twenty-eight pregnancies were obtained in 140 treatment cycles. Couples are accepted for treatment in our IVF-ET programme if previous semen samples fulfil the inclusion criteria: ejaculate volume greater than 1.5 ml, concentration of spermatozoa greater than 15 x 10(6) ml-1, greater than 40% motile spermatozoa, and greater than 25% spermatozoa with normal morphology. In order to determine to which extent IVF-ET treatment results are influenced by sperm morphology, within this selected group of patients, we have retrospectively analysed the data from both original semen samples and swim-up preparations. The sperm morphology was not related to the outcome of treatment in terms of fertilization (ovum cleavage rate), early embryo development, or pregnancy. Nor was any relationship detected between early embryo development or pregnancy and the degree of improvement in morphology resulting from the swim-up procedure. However, if improvement in morphology by swim-up was high, ovum cleavage rate was low. Sperm morphology within the limits set by our inclusion criteria could not predict the outcome of IVF-ET treatment. It is further concluded that the presence of abnormal spermatozoa at the site of fertilization may be without harm if only the number of normal sperms is high enough.

Embryo Transfer↗
PubMedDate not supplied

Comparison between a conventional index of progressive sperm motility and movement variables analysed by CellSoft.

Two different techniques of human sperm motion analysis were compared. In 25 ejaculates, diluted to an appropriate concentration, the sperm motion index called "specific progressive motility" (SPM) was assessed by a modified conventional method. The same sperm preparations were also analysed by the CellSoft system for computer assisted sperm analysis (CASA). The SPM-value was found to correspond mainly to the variables motility and curvilinear velocity presented by CASA (multiple r = 0.92, P less than 0.001). Linearity of sperm progression, lateral head displacement, and beat cross frequency did not significantly contribute to the relationship between SPM and CASA. For comparative studies between SPM and CASA the logarithmic values of SPM are recommended.

Autoanalysis↗