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Biomedical subjects

L Vermeulen

Publications and source records attributed to L Vermeulen.

35 records · Page 2Linked to original sources
PubMed1989

Determination of adenosine triphosphate in human semen to estimate the fertilizing potential and to quantify sperm antibodies.

The measurement of the ATP content of fresh semen is as accurate as the estimation of sperm motility by conventional methods in discriminating between semen of fertile versus subfertile men. The ATP content of frozen thawed donor semen is correlated with the probability of conception per cycle of insemination. Exact quantification of cytotoxic sperm antibodies in serum is possible with the adenosine-triphosphate-release-cytotoxicity test, since measurement is free of the bias of microscopic examination. The procedure has been simplified by testing only one serum dilution and calculating the 'sperm toxicity index'.

Adenosine Triphosphate↗
PubMed1989

Effect of different procedures of semen preparation on antibody-coated spermatozoa and immunological infertility.

To assess whether procedures of semen preparation can reduce the proportion of antibody-coated spermatozoa, semen samples with positive direct mixed antiglobulin reaction (MAR) were washed in media supplemented with 10% or 50% fetal cord serum (FCS). Washing reduced the MAR to a negative level, but the MAR was identical to that in the native semen when spermatozoa were resuspended in serum-free medium. Donor spermatozoa, recovered after swim-up in media supplemented with 10% or 50% FCS or after passage through a column with 7.5% human serum albumin (HSA), were incubated in serum samples with both agglutinating and cytotoxic antisperm antibodies. Cytotoxic activity was significantly reduced against sperm filtered over the albumin column.

Agglutinins↗
PubMed1988

Accuracy of sperm characteristics in predicting the in vitro fertilizing capacity of semen.

Based on the results of in vitro fertilization (IVF) in 56 couples, the power was assessed of traditional sperm characteristics of native semen to discriminate between in vitro fertile and in vitro infertile semen. The number per ejaculate of spermatozoa with regular oval heads was the best discriminant, followed by the concentration of progressively motile spermatozoa. This contrasts with the in vivo fertilizing capacity, which depends mostly on the proportion and concentration of spermatozoa with rapid linear progression. The lower limit of sperm characteristics was assessed as the fifth percentile of in vitro fertile semen and was compared with the lower limit of semen of fertile men and of subfertile men who achieved spontaneous or treatment-related conception in vivo. It appeared that the semen quality needed for in vitro fertilization is inferior to that of fertile men but not remarkably different from that of subfertile men who achieved spontaneous conception during 1-year follow-up after consultation. If conventional methods for semen preparation are used, there seems to be no major advantage in favor of IVF for the treatment of male infertility due to sperm deficiency. An increased success rate may, however, be attained, thanks to improved techniques of semen collection, semen preparation, and oocyte insemination.

Female↗
PubMed1988

Evaluation of a simplified adenosine triphosphate release cytotoxicity test for the detection of sperm antibodies in human serum.

The adenosine triphosphate release cytotoxicity test (ARCT) is an objective method for the detection of cytotoxic sperm antibodies in serum providing measurements without the bias of microscopic estimation. The procedure has been simplified by testing only one serum dilution and calculating the "sperm toxicity index". The latter is closely correlated with the sperm cytotoxic titer. Immunoglobulin class determination of 32 sera with sperm cytotoxic activity was performed by means of the indirect mixed antiglobulin reaction (MAR test) and the indirect immunobead (IB) test, and revealed that all sera were positive for IgG, 17% for IgM and 20% for IgA. Of 32 sera without sperm cytotoxic activity, 19% contained sperm specific IgG, 6% had IgM class antibodies belong mainly to the IgG class since the results of the ARCT and the indirect MAR test for IgG are closely correlated. The ARCT appears to be useful as a simple and objective method for the detection and quantitation of cytotoxic antisperm antibodies.

Adenosine Triphosphate↗
PubMed1988

The indirect mixed antiglobulin reaction test using a commercially available kit for the detection of antisperm antibodies in serum.

A simple procedure is described for the detection of antisperm antibodies of the IgG class in human serum using the indirect mixed antiglobulin reaction (MAR) test. The test uses only one dilution of serum (1/16) and no washing procedures. The test was performed in 361 sera. Comparative studies were conducted with the tray agglutination test (TAT) in 164 sera and with the direct MAR test on semen in 110 cases. In 24 sera with borderline test results, and in 13 sera with discordant findings, evidence of antisperm antibody activity was investigated by means of additional testing, namely, the adenosine triphosphate release cytotoxicity test (ARCT) and the indirect immunobead tests (IB) for IgA and IgM. Using the value of 40% reaction between motile spermatozoa and coated latex particles as the lower limit of significant activity, the indirect SpermMAR test has a sensitivity of 96% and specificity of 87%. The two false-negative indirect MAR results occurred in cases with IgM, the clinical significance of which is doubtful. Hence, the indirect MAR test appears to be an ideal screening procedure for sperm antibodies in serum since it is easy to perform and sensitive. Considering the false-positive rate of 13%, additional tests should, however, be performed on sera with a reaction of 40% or more in order to assess the relevance of the antibodies as a cause of infertility.

Agglutination Tests↗
PubMed1988

Evaluation of the direct and indirect mixed antiglobulin reaction with latex particles for the diagnosis of immunological infertility.

The direct Mixed Antiglobulin Reaction (MAR test) is a simple method for the detection of auto-antibodies attached to spermatozoa in fresh semen. The test was improved by using IgG-coated latex particles (SpermMAR) instead of coated red blood cells. A positive direct MAR test with adherence of latex particles to 40% or more of the motile spermatozoa was found in 16 out of 312 men (5%) consulting for infertility, but never in fertile controls. The percentage of motile spermatozoa reacting with the coated latex particles was correlated significantly with the serum titre of sperm agglutinins assessed by the tray agglutination test. The direct MAR test on semen was highly specific but rather insensitive, particularly if the serum titre of agglutinins was low. The same kit (SpermMAR) can be used to detect circulating sperm antibodies in serum of male or female patients with the indirect mixed antiglobulin reaction. The indirect MAR test discriminated clearly between serum with low (less than 1/32) or high (greater than 1/32) titres of circulating agglutinins assessed by the tray agglutination test. Considering their simplicity and accuracy, both the direct test on semen and the indirect spermMAR test on serum should be included in the routine evaluation of the infertile couple.

Antibodies, Anti-Idiotypic↗
PubMed1987

Reassessment of the accuracy of traditional sperm characteristics and adenosine triphosphate (ATP) in estimating the fertilizing potential of human semen in vivo.

Receiver operating characteristic curves and accuracy parameters were computed for traditional sperm characteristics (concentration, motility, morphology) and the number of peroxidase negative cells, and the concentration of adenosine triphosphate (ATP) in semen from populations of fertile and infertile men, and men who achieved a pregnancy after varicocele treatment. The percentage and concentration per millilitre of spermatozoa with rapid linear progressive motility, and the ATP concentration, provided the best discrimination between fertile and treated fertile from infertile men. The misclassification rate was higher for sperm morphology, total progressive motility and viability, whereas sperm concentration and the total sperm count per ejaculate had the worst discriminating power. The number of peroxidase negative cells per 100 spermatozoa was highly specific in identifying men who achieved pregnancy after varicocele treatment. The lower limit of normality of sperm characteristics was remarkably different between fertile men and men achieving pregnancy after treatment or during infertility work-up.

Adenosine Triphosphate↗
PubMed1985

Altered glycosylation of gamma-glutamyltranspeptidase (GGT) in seminal fluid from men with accessory gland infection.

The heterogeneity of gamma-glutamyltranspeptidase (GGT) in seminal plasma has been studied using Con A-chromatography. This parameter was then related to the fructose concentration, the acid phosphatase activity, ejaculate volume, sperm density and the number of bacteria per ml. Multivariate regression analysis and stepwise elimination of the least fitting factors, revealed that Con A-binding correlated with the number of bacteria per ml of semen and the acid phosphatase activity with 49% of the variance of GGT-binding being explained by these parameters. This result suggests that glycosylation of seminal GGT is altered by accessory gland infection. Neuraminidase digestion suggests that the pattern of Con A-binding of seminal GGT depends only partly on its sialic acid content.

Acid Phosphatase↗
PubMed1983

Adenosine triphosphate in human semen: a quantitative estimate of fertilizing potential.

The concentration of adenosine triphosphate (ATP) per milliliter of ejaculate was found to be significantly correlated with the following parameters: sperm concentration, number of motile spermatozoa per milliliter, capacity of spermatozoa to migrate against gravity, and in vitro potential to penetrate zona-free hamster ova. The ATP concentration was significantly lower in the semen of infertile men with normal sperm concentration and motility, compared with matched fertile donors. The ATP concentration of deep-frozen donor semen was significantly correlated with its fertilizing potential as estimated from the pregnancy per cycle index in an artificial insemination by donor semen program. These qualities suggest that measurement of semen ATP may be a possible biochemical method for the quantitation of the actual fertilizing potential of the ejaculate.

Adenosine Triphosphate↗
PubMed1983

Testicular arterial perfusion in varicocele: the role of rapid sequence scintigraphy with technetium in varicocele evaluation.

Rapid sequence scintigraphy was used to study testicular arterial perfusion and venous stasis in 53 patients with varicocele-associated infertility, 17 with idiopathic testicular failure and 9 treated for varicocele. Arterial blood supply to the diseased testicle was decreased in 63 per cent of the patients with subclinical or low grade varicocele compared to 18 per cent with idiopathic testicular failure. In the majority of cases the disturbance of perfusion disappeared immediately after interruption of retrograde blood flow in the internal spermatic vein by transcatheter embolization, whereas persistently impaired perfusion was found in a few cases with no improvement of semen quality after treatment. Venous stasis was found in only 18 per cent of the patients with low grade varicocele compared to 88 per cent with large varicoceles. It is suggested that impaired arterial blood supply rather than venous stasis is the pathogenic factor in epididymo-testicular dysfunction associated with low grade varicocele.

Humans↗
PubMed1983

Effect of high dose oral Kallikrein treatment in men with idiopathic subfertility: evaluation by means of in vitro penetration test of zona free hamster ova.

High dose oral Kallikrein treatment (600 U Padutine per day) was given to 10 infertile men with poor semen quality. After 3 months of this treatment no pregnancies occurred, and no significant changes in routine semen characteristics were observed. Moreover, the capacity of the spermatozoa to migrate in vitro and to penetrate zona free hamster ova remained unchanged after Kallikrein ingestion. It is concluded that Kallikrein treatment was ineffective in these men.

Animals↗
PubMed1981

The role of hyperphagia and hypothyroidism in the development of the obese-hyperglycemic syndrome in mice (ob/ob).

Obese-hyperglycemic mice show hyperphagia and hypothyroidism. The reduced body temperature can be normalized by injection of thyroxin. Limiting food intake to normal non-obese levels reduces blood sugar level, insulin content of the blood and body weight. However, reduction of all these parameters together until normal level occurs only when combining thyroxin injection with restricted diet. Weight of epididymal fat pad, nuclear volume of Leydig cells and volumes of islets of Langerhans normalize too during the combined treatment. It is argued that in adult obese mice hyperphagia and hypothyroidism are two separate factors which cannot be completely compensated for one by another. At least some symptoms in the obese-hyperglycemic syndrome could be attributed to hypothalamic disturbances caused by a reduced thyroidal activity at a very early age after birth.

Animals↗
PubMed1980

Diagnosis of accessory gland infection and its possible role in male infertility.

The diagnosis of male adnexitis is difficult and the influence of this condition on fertility is still a matter of debate. With the intention to define diagnostic criteria a comprehensive study of biochemical and morphological features of semen, plus culture for microorganisms, was performed in patients who were assessed for infertility during a four year period. The following parameters were considered of diagnostic value: a) history of urogenital infection and/or abnormal rectal palpation. b) significant alterations in the expressed prostatic fluid and/or urinary sediment after prostatic massage. c) 1. Uniform growth of more than 10(3) pathogenic bacteria, or more than 10(4) non-pathogenic bacteria per ml, in culture of diluted seminal plasma. c) 2. Presence of more than 10(6) (peroxidase positive) leucocytes per ml of ejaculate. c) 3. Signs of disturbed secretory function of the prostate or seminal vesicles. The diagnosis of infection is accepted if either of the following combinations if found: a + b, a + c (1 or 2 or 3), b + c (1 or 2 or 3), c1 + c2, c1 + c3, c2 + c3.

Acid Phosphatase↗
PubMedDate not supplied

Study of the accuracy of physical and biochemical markers in semen to detect infectious dysfunction of the accessory sex glands.

Infection of the male accessory sex glands may result in impaired secretory function and alteration of the composition of seminal plasma. Using receiver operating characteristic curves and accuracy tests, the power of several biochemical and physical markers was evaluated for their ability to discriminate between semen of infected and noninfected infertile men. The total output of citric acid had the strongest discriminating power, followed by acid phosphatase and gamma-glutamyltranspeptidase. Measurement of the concentration of fructose was found to be nondiscriminatory.

Acid Phosphatase↗
PubMedDate not supplied

Evaluation of the hypo-osmotic swelling test in relation with advanced methods of semen analysis.

The hypo-osmotic swelling test was claimed to assess an independent functional characteristic of human spermatozoa bearing relevance to their fertilizing capacity. To test this claim, we have studied the relationship between the result of the hypo-osmotic swelling test with that of conventional semen analysis and sperm motility patterns, the semen content of adenosine triphosphate, the staining pattern to acidified aniline blue, and the zona-free hamster oocyte test. The result of the HOS test is significantly correlated with all sperm characteristics except for the aniline blue stainability and the hamster oocyte test. The capacity of spermatozoa to react in a hypo-osmotic environment expresses the same functional information as the viability test using eosine staining. It is concluded that the hypo-osmotic swelling test does not add relevant information to that obtained by routine sperm analysis with regards to the fertilizing potential of semen.

Adenosine Triphosphate↗
PubMedDate not supplied

Comparison between cell motion analyser, autosperm, and conventional semen analysis.

With the aim of explaining some of the controversy on the value of computer-assisted methods of semen analysis, a study was conducted comparing the fully automated cell motion analyzer (CMA), the semi-computerized autosperm system (AS) and the conventional manual method. The CMA equipment gave higher values for sperm concentration than the mean of the three methods. Sperm concentration estimated with the conventional method was below the average of the three methods. The conventional method overestimated sperm motility, which was underestimated by CMA. The correlation between sperm velocity characteristics estimated by CMA and AS was significant, but only 18% of variability of one method could be explained by variability of the other. The reasons for the discrepancy between velocity measurements in the two methods are discussed in relation to possible shortcomings in sperm paths smoothing using the CMA method and the effect of technician training in the AS method. The AS method was found to provide more reproducible results which correlated better with those of the manual method as recommended by the World Health Organization.

Autoanalysis↗