Spectrophotometric application of resazurin reduction assay to evaluate boar semen quality

The resazurin reduction assay depends on the ability of metabolically active cells to reduce the resazurin redox dye to resorufin. In the present study we applied and made a diagnostic evaluation of a spectrophotometric application of the resazurin reduction assay to assess the colour change of resazurin reduction in butanol extracted colour to evaluate boar semen quality. Forty-one samples of boar semen from various breeds were included in the study. The absorption peaks for resazurin and resorufin were found to be 610 and 575 nm, respectively. Absorbance at 610 nm, where the minimum overlap of the two peaks was observed, was used in further analysis. Spearman rank correlation analysis was used to determine the correlation between the resazurin reduction assay and various semen parameters. The highest correlations were observed with the concentration of motile spermatozoa (r = -0.841; p < 0.001), sperm concentration (r = -0.833; p < 0.001), sperm index (-0.826; p < 0.001) and concentration of viable spermatozoa (r = -0.763; p < 0.001). Sensitivity and specificity, at 94.1 and 91.7%, respectively, indicate that the present test is highly accurate in discriminating between the samples according to the sperm index. When motile sperm concentration was used to distinguish between good and poor samples, high sensitivity (93.6%) was also found, whereas the test was only moderately, 80%, specific. The stability of butanol extracts in terms of A610 at different times of measurement confirmed that the resazurin reduction could be spectrophotometrically measured within 7 days from the time of assay performance, making the assay much more useful. Based on these results, the assay could be used as an additional tool for evaluating the quality of boar semen.     

Evaluation of sperm fertilizing ability using the Sperm Quality Analyzer

The Sperm Quality Analyzer is an inexpensive device which provides a quantitative estimation of sperm motility. To evaluate the fertilizing ability of human spermatozoa using a Sperm Quality Analyzer, correlations amongst the sperm motility index, the sperm penetration index (as assessed using the sperm penetration assay; SPA), and the fertilization rate in the treatment of standard IVF-ET were analysed retrospectively. The sperm motility index demonstrated a significant correlation with sperm concentration ( p  < 0.001), sperm motility ( p  < 0.001) and the motile sperm concentration ( p  < 0.001) in a total of 104 fresh semen samples from 81 men donating samples for IVF-ET. The sperm motility index also showed a significant correlation ( p  < 0.001) with the sperm penetration index in 60 patients, assessed using the SPA, before they were treated by standard IVF-ET. The correlation between the sperm motility index and the IVF-ET fertilization rate was higher than that between the sperm penetration index and the fertilization rate. The sperm motility index was classified into three categories: `poor' (sperm motility index < 80), `medium' (sperm motility index 81–160) and `good' (sperm motility index>  160). The relationships between the IVF-ET fertilization rate and each category of the sperm motility index values were also evaluated. For the three categories in the sperm motility index, the fertilization rates (76.0%) of 60 samples judged as `good' were significantly higher than those (44.2%) of 15 samples judged as `medium' ( p  < 0.001) and those (34.7%) of 13 samples judged as `poor' ( p  < 0.001). These results indicate that the Sperm Quality Analyzer provides a reliable estimation of the fertilizing ability of human spermatozoa.     

Separation of human spermatozoa with hyaluronic acid induces, and Percoll® inhibits, the acrosome reaction

The effect on the acrosome reaction of human spermatozoa of two widely used sperm separation media, hyaluronic acid (Sperm Select®) and Percoll®, was studied. Viable and highly motile fractions of human spermatozoa were separated from seminal plasma using self-migration on a Percoll® gradient. After translocation of separated spermatozoa from the Percoll® solution to a culture medium, serum, Percoll® or hyaluronic acid (Sperm Select®) was added to aliquots of the spermatozoa containing culture medium. At increasing time intervals, the influx of ⁴⁵Ca²⁺ into spermatozoa was measured and the concentration of viable spermatozoa that had undergone the acrosome reaction was analysed using the triple stain technique. Serum was found to be necessary to support sperm motility and viability. Compared to culture medium with serum only, addition of hyaluronic acid induced influx of ⁴⁵Ca²⁺ and the acrosome reaction, whilst Percoll® inhibited both of these actions. Hyaluronic acid (Sperm Select®) added to spermatozoa separated by a 'swim-up' method induced, and the addition of Percoll® inhibited, influx of ⁴⁵Ca²⁺ when compared to the addition of culture medium with serum only. This study demonstrates that both hyaluronic acid (Sperm Select®) and Percoll® affect the acrosome reaction and the prerequisite for Ca²⁺ influx in human spermatozoa. These effects should be taken into consideration when using these media for preparation of spermatozoa for insemination or for fertilization in vitro.     

Influence of fibronectin on the motility of human spermatozoa

The objective of the present study was to scrutinize the concentration of seminal fibronectin and the potential effects of exogenous fibronectin on human sperm motility. In addition, variability in the localization of fibronectin on human spermatozoa from andrological patients was studied, at both the light and electron microscopic levels. A total of 58 freshly ejaculated semen samples from patients attending for infertility treatment were submitted to sperm motility analysis and ELISA quantification of seminal plasma and cell-bound fibronectin. Immunofluorescence and immunoelectron microscopy revealed a relatively broad distribution pattern of fibronectin immunoreactivity on sperm heads and testicular spermatids. Addition of a fibronectin antiserum to vital spermatozoa in vitro at a moderate dilution (1:50) resulted in a significant increase in sperm motility. Purified plasma fibronectin, added at various concentrations to a preparation of live spermatozoa, was found to inhibit sperm motility in a dose-dependent manner. At concentrations from 0.18 to 0.5 mg fibronectin per ml ejaculate, no motile spermatozoa were recorded. Seminal plasma fibronectin ranged between 0.8 and 1000 μg/ml in infertility patients. There was a significant inverse correlation between sperm motility and seminal fibronectin in patients with oligo-astheno-teratozoospermia. In a preliminary study in patients with varicocele or hypogonadism, no such correlation was found.     

Mast cells in the seminal plasma of infertile men as detected by flow cytometry

Increased numbers of mast cells (MCs) in the testis have been associated with testicular dysfunction, where accumulation of MCs occurs. Furthermore, it has been reported that MCs might affect sperm function as it has been demonstrated that MC-derived tryptase in the seminal fluid might reduce sperm motility. Although MCs have been detected in rat epididymis, only little is known about the presence of MCs in human seminal plasma. Thus, we analysed MC numbers in the ejaculate of men during routine semen analysis of male patients suspected for infertility ( n  = 100). MCs were detected by c-kit (CD117) expression using flow cytometry. Thereby, we detected significant numbers of MCs in the ejaculate of most patients (559 ± 525 MCs ml⁻¹, mean ± SD). However, we could neither detect a correlation with respect to MCs and sperm count, motility or morphology nor to the seminal inflammatory markers like polymorphonuclear elastase. Nevertheless, a significant correlation of MCs to spermatozoa-bound IgA ( r  = 0.5; P  = 0.03; n  = 21) was observed. It is concluded that significant numbers of MCs can be detected in the human ejaculate without necessarily influencing sperm function. A potential role of MCs in seminal plasma as well as the association between MCs and IgA on spermatozoa remains to be elucidated.     

Heme oxygenase enzyme activity in seminal plasma of oligoasthenoteratozoospermic males with varicocele

This work aimed to assess seminal plasma heme oxygenase (HO) enzyme activity in oligoasthenoteratozoospermia (OAT) males with varicocele. Ninety‐three men were divided according to their sperm count and clinical examination into: healthy fertile controls (n = 34), OAT without varicocele (n = 37) and OAT associated with varicocele (n = 22). They were subjected to semen analysis and estimation of seminal plasma HO enzyme activity in the form of bilirubin concentration. Seminal plasma HO enzyme activity decreased significantly in OAT cases compared with controls. Seminal plasma HO in OAT cases associated with varicocele decreased significantly compared with OAT cases without varicocele and healthy controls (mean ± SD; 109.2 ± 29.5, 283.6 ± 88.4, 669.5 ± 236.1 nMol bilirubin/mg ptn/min, P < 0.001). There was positive correlation between seminal plasma HO enzyme activity and sperm concentration, per cent of motile spermatozoa, number of motile spermatozoas ml^?1 and significant negative correlation with sperm abnormal forms per cent. It is concluded that varicocele has a negative impact on seminal HO enzyme activity. Therefore, improved seminal picture after correcting varicocele repair might be related, in part, to improved HO action(s).     

Supplementing oregano essential oil to boar diet with strengthened fish oil: Effects on semen antioxidant status and semen quality parameters

Previous research has shown benefits of dietary fish oil supplementation on semen quality of boars. However, little is known about how antioxidant protects lipid peroxidation on spermatozoa from n‐3 polyunsaturated fatty acid (PUFA) addition. This study evaluated the effect of oregano essential oil (OEO) supplementation on semen antioxidant status and semen quality in boars fed a diet enriched with fish oil. Thirty‐four mature boars of proven fertility, received daily 2.5 kg basal diet top‐dressed with 45 g soybean oil and 15 g fish oil to meet the n‐3 PUFA requirement of spermatozoa, randomly allocated to one of four groups supplemented with 100 mg α‐tocopheryl acetate kg^?1 (control), or 250 or 500 or 750 mg OEO kg^?1 for 16 weeks. Semen was collected at weeks 0, 8, 12 and 16 for measurements of sperm production, motion characteristics, sperm α‐tocopherol content, antioxidant enzyme activities, reactive oxygen species (ROS), DNA damage (8‐hydroxydeoxyguanosine, 8‐OHdG), lipoperoxidation (malondialdehyde, MDA) and seminal total antioxidant capacity (TAC). Sperm production and motion characteristics were similar (p > .05) among groups throughout the experimental week 16, but increased (p < .01) with experimental week. Although higher α‐tocopherol content and superoxide dismutase (SOD) activities were in OEO group spermatozoa, feeding diet with 500 mg/kg OEO resulted in elevation in seminal TAC, decrease in sperm ROS, MDA and 8‐OHdG than control group (p < .05). Overall, these results support the view that oregano essential oil has a positive effect on antioxidant capacity in boar when used fish oil.     

Determination of the diagnostic value of the resazurin reduction assay for evaluating boar semen by receiver operating characteristic analysis

Aim： To assess that metabolic status of spermatozoa could provide a useful tool for evaluation of semen quality. Methods： The accuracy of the spectrophotometric application of the resazurin reduction assay was assessed using receiver operating characteristic （ROC） analysis. Results： Areas under ROC curves （AUC） for motile sperm concentration and sperm index （SI） （sperm concentration multiplied by the square root of percentage sperm motility multiplied by the percentage normal sperm morphology） were 0.922. The best discrimination between poor and good semen samples according to the SI was achieved at a cut-off point of A610 = 0.209, where high sensitivity （94.1%） and specificity （91.7%） were calculated. The assay was less accurate when motile sperm concentration was used as the criterion value, yielding sensitivity of 88.2% and specificity of 87.5%, respectively. Likelihood ratios （LR） indicate that absorbances lower than 0.209 were at least 11.3 times as likely to be found in good semen samples than those in poor according to the SI, whereas in the case of motile sperm concentration, the LR was calculated to be 7.06. Conclusion： These results show that the resazurin reduction assay combined with spectrophotometry is an accurate method of assessing the quality of boar semen.     

Sperm telomere length in motile sperm selection techniques: A qFISH approach

Several studies have associated telomere shortening with alterations in reproductive function. The objective of the present study was to determine telomere length (TL) in spermatozoa selected by either density‐gradient centrifugation (DGC) or swim‐up. The analysis of TL was performed using quantitative fluorescent in situ hybridisation (qFISH) using PNA probes in combination with a chromatin decompaction protocol in sperm cells. Results of TL were 24.64 ± 5.00 Kb and 24.95 ± 4.60 Kb before and after DGC, respectively, and 19.59 ± 8.02 Kb and 20.22 ± 5.18 Kb before and after swim‐up respectively. Sperm selected by DGC or swim‐up did not show any significant differences in TL as compared to nonselected sperm (p > .05). Negative correlations between TL and sperm motility (r = ?.308; p = .049) and concentration (r = ?.353; p = .028) were found. Furthermore, exposure of sperm to increasing concentrations of hydrogen peroxide during incubation resulted in a reduction in TL. These data indicate that oxidative stress may be one of the main factors involved in the reduction of TL in sperm. Preliminary clinical results from patients included in this study indicate that TL was shorter in spermatozoa from couples who never achieved a pregnancy compared to couples who did achieve at least one natural pregnancy (p < .05); however, the clinical utility of this biomarker still needs to be confirmed in further studies.     

A human seminal plasma protein blocks the motility of human spermatozoa

An inhibitor of the motility of demembranated spermatozoa has been shown to be present in human seminal plasma. This seminal plasma motility inhibitor (SPMI) was purified to apparent homogeneity and tested on intact human spermatozoa. Motility parameters of spermatozoa incubated with the sperm motility inhibitor were evaluated with the video automated Cell Soft system. SPMI decreased the percentage of motile spermatozoa in a dose-dependent manner and motility was completely blocked in the presence of 1600 units/ml. Sperm velocity and beat/cross frequency showed a similar progressive decrease as the inhibitor was augmented. However, linearity was essentially not affected. The effects of SPMI on the percentage of motile spermatozoa increased with the time of contact between the inhibitor and spermatozoa. After 120 min., the IC50 was 35% lower than that observed at five min. The presence of seminal plasma did not prevent the inhibitory effects of the seminal plasma factor on sperm motility parameters. On the contrary, a potentiating effects was observed. The data suggest that the SPMI could play a significant role in cases of infertility caused by asthenospermia.     

DNA hydroxymethylation rate in the AChE and HoxC4 promoter associated with human sperm quality

The relationship of altered DNA 5′‐hydroxymethylation in human spermatozoa with seminal parameters remains unclear. The aim of the study was to investigate the association between the 5′‐hydroxymethylcytosine (5hmC) rate in the promoters of acetylcholinesterase (AChE) and homeobox C4 (HoxC4) genes and human sperm concentration/motility. The study population consisted of three groups: asthenozoospermia (AZ), oligoasthenozoospermia (OAZ) and normozoospermia (NZ). The 5hmC rate in the promoter was measured by CCGG loci‐dependent MspI/HpaII restriction mapping of glycosylation‐modified sperm DNA combined with a hydroxymethylation‐specific real‐time polymerase chain reaction assay. The 5hmC rate in the AChE promoter in group AZ and OAZ was higher than that in group NZ (p < .05). A weak inverse correlation between 5hmC rate of AChE and sperm motility was observed in all subjects (r = ?.172, p < .05). The 5hmC rate in the HoxC4 promoter in group OAZ was lower than that in group NZ (p < .05). These results indicated that altered 5hmC rates of AChE and HoxC4 promoters are associated with low sperm motility and sperm concentration respectively.     

Effect of calmodulin-like protein from buffalo (Bubalus bubalis) seminal plasma on Ca2+, Mg2+-ATPase of purified plasma membrane of buffalo spermatozoa

Summary. Buffalo sperm heads and tails were cleaved by sonication and isolated in relatively pure proportions i.e. 95% and 98% respectively, by discontinuous sucrose density-gradient centri-fugation. Purified plasma membranes from the isolated sperm heads and tails were obtained by hypotonic treatment and brief sonication followed by discontinuous sucrose density-gradient centrifugation. Ca²⁺, Mg²⁺-ATPase activity was evident in plasma membrane from sperm heads and tails, although activity was greater in the latter. A calmodulin-like protein isolated from buffalo seminal plasma increased the Ca²⁺, Mg²⁺-ATPase of plasma membrane from the sperm heads and tails by 128 and 136% respectively. Based upon the data obtained here and elsewhere (Sidhu & Guraya, 1989a) a model is proposed which explains regulation of Ca²⁺ in buffalo spermatozoa and implicates calmodulin-like protein and Ca²⁺, Mg²⁺-ATPase in sperm acrosome reaction.     

Immunoreactive relaxin in seminal plasma of fertile boars and its correlation with sperm motility characteristics determined by computer-assisted digital image analysis

Ejaculates from 10 mature fertile large white Yorkshire boars were used to examine the correlation between immunoreactive relaxin levels in seminal plasma and sperm motility characteristics. Seminal plasma levels of immunoreactive relaxin were measured by a time-resolved fluoroimmunoassay (TR-FIA). Motility characteristics were assessed using a CellSoft computer-assisted digital image analysis system. The mean +/- SD level of immunoreactive relaxin in seminal plasma was 2.61 +/- 0.62 ng/mL. When the correlation between seminal plasma levels of immunoreactive relaxin and parameters of sperm movement was examined, it was found that relaxin levels were significantly correlated with the percentage of motile spermatozoa (r=0.687, p < 0.05), curvilinear velocity (r=0.745, p < 0.05), straight line velocity (r=0.651, p < 0.05), mean amplitude of lateral head displacement (mean ALH) (r=0.844, p < 0.01) and the maximum amplitude of lateral head displacement (max ALH) (r=0.830, p < 0.01), but not with linearity, beat-cross frequency, or percentage of circular cells. Among these parameters, seminal plasma levels of immunoreactive relaxin showed the strongest correlation with the ALH parameter related to fertilizing ability. These results indicate that immunoreactive relaxin in boar semen may be necessary not only for normal sperm motility but also for normal fertility, suggesting that determination of the profile of immunoreactive relaxin in ejaculates may have value as a potential marker for predicting sperm fertilizing ability of boars.     

Catalase supplementation on thawed bull spermatozoa abolishes the detrimental effect of oxidative stress on motility and DNA integrity

The potential protective effect of catalase supplementation during in vitro culture of frozen/thawed bull spermatozoa was investigated. Frozen/thawed semen collected from three fighting bulls was diluted in phosphate buffered saline (PBS) and incubated at 37 °C under different experimental conditions: Control, Catalase (CAT) (200 U/mL), Oxidant (OXI) (100 μ m Fe²⁺/1 m m ascorbate), and Catalase + Oxidant (CAT/OXI). We assessed sperm motility, acrosomal integrity, viability and chromatin status (SCSA®) at 0, 2 and 6 h of incubation. Our results showed that catalase abolished the effect of the oxidant, protecting spermatozoa against reactive oxygen species, and improving both sperm motility and chromatin status during incubation. The OXI treatment significantly reduced the percentage of motile sperm after 6 h of incubation. The statistical model also showed that there were differences in sperm motility between CAT/OXI (20.8 ± 2.9%) and OXI (11.6 ± 7.6%) ( p  < 0.001). There were no significant effects of OXI on sperm viability, acrosomal status or proportion of abnormal tails. %DFI (spermatozoa with moderate or high DNA Fragmentation Index) was significantly higher on OXI ( p  < 0.001). Catalase prevented DNA fragmentation even in the presence of the oxidant (%DFI: 30.3 ± 0.8% OXI vs. 17.4 ± 0.7% CAT/OXI). We conclude that catalase supplementation after thawing could protect bull spermatozoa against oxidative stress, and it could improve media used for processing thawed spermatozoa.     

Cadmium, lead, selenium, and zinc in semen of occupationally unexposed men

Summary. Concentrations of cadmium, lead, selenium, and zinc were determined in semen and seminal plasma of 22 volunteers by atomic absorption spectrometry. Additionally conventional semen parameters and, by means of computer videomicrography, motion parameters of spermatozoa were evaluated. Concentrations of Cd, Pb, and Zn determined in semen were not significantly different from those measured in seminal plasma. However, selenium levels were significantly higher in semen (53.8 ± 22.9 μg 1⁻¹) than in seminal plasma (40.4 ± 15.5 μg 1⁻¹, P <0.01). The investigated semen samples on average contained low levels of Cd (0.4 ± 0.23 μg 1⁻¹) and Pb (9.8 ± 6.5 μg 1⁻¹). Studies on the intra-individual variability revealed the following average coefficients of variation (%) for element concentrations: Pb (70), Cd (53), Se (27), and Zn (23); and for semen parameters: total sperm count (46), sperm concentration (37), motility (22), ejaculate volume (21), linearity (19), linear velocity (11), curvilinear velocity (10), and percentage of normally formed sperm (9). Significant positive correlations were detected between semen selenium levels and sperm concentration ( r =0.51, P <0.05), and percentage of normally formed sperm ( r =0.46, P <0.05), respectively. Sperm motility ( r =0.53, P <0.02), linear ( r = 0.76, P <0.001) and curvilinear velocity ( r = 0.64, P < 0.002) were significantly correlated with semen cadmium levels.     

Secretion of macromolecules by the rat epididymis

Sperm maturation in the rat epididymis is dependent on the secretion of specific proteins by the epididymal epithelium and subsequent interaction of these proteins with spermatozoa. Evidence has shown that fertility and motility development of epididymal spermatozoa may be impaired by interfering the interaction of these proteins with spermatozoa. When the spermatozoa reach the cauda epididymidis, they are fully mature but their longevity is maintained by being stored in a quiescent state in the cauda. The unique ionic medium therein (low Na⁺, low Ca²⁺, high K⁺ and low pH) suppresses sperm motility and hence reserving energy for the vital processes of capacitation and fertilization. During ejaculation, when the spermatozoa are mixed with the copious secretion from the accessory glands they burst into vigorous motility. This results from an influx of sodium coupled to efflux of K⁺ and H⁺ across the mature sperm membrane. In the presence of a peptide secreted by the cauda epididymidis, these ionic events activate the already mature but otherwise inactive spermatozoa to full motility.     

Survival of buffalo bull spermatozoa: effect on structure and function due to alpha‐lipoic acid and cholesterol‐loaded cyclodextrin

Sperm survival depending upon integral membranes and function is imperative for fertilization. This study was designed to augment survival of buffalo spermatozoa using alpha‐lipoic acid (ALA) and cholesterol‐loaded cyclodextrin (CLC) during cryopreservation. Semen was frozen using 0, 0.5, 1, 1.5, 2 and 2.5 mmol L^?1 ALA (experiment 1) and ALA or CLC separately or together (experiment 2). Semen was assessed for post‐thaw motility, plasma membrane integrity (PMI), intact acrosome and plasma membrane (IACR‐IPM) and DNA integrity at 0, 1.5, 3 and 4.5 hr of incubation. In experiment 1, use of 0.5 mmol L^?1 ALA enhanced the sperm cryosurvival and post‐thaw longevity than other groups up to 4.5 hr of incubation, and this concentration of ALA was used in second experiment with CLC. The results revealed higher (p < .05) sperm survival function and time of sperm attributes due to use of ALA than CLC and control. However, the sperm quality did not improve (p > .05) when ALA was combined with CLC. In conclusion, survival of buffalo bull spermatozoa during freeze‐thawing and post‐thaw incubation can be enhanced more with ALA than CLC or control, followed by CLC than control. However, there is no synergistic effect on survival of buffalo bull spermatozoa due to ALA and CLC.     

Porcine sperm vitrification I: cryoloops method

The aims of this study were to evaluate porcine sperm vitrification in cryoloops, with and without two different cryoprotectants and assess two warming procedures. Extended (n = 3; r = 4) and raw (n = 5; r = 2) semen was diluted in media without and with cryoprotectants (4% dimethylformamide and 4% glycerol) to a final concentration of 20 × 10⁶ spermatozoa ml^?1 and vitrified using the cryoloops method. Two warming procedures were evaluated: rapid method (30 s at 37°C) and an ultra‐rapid method (7 s at 75°C, followed by 30 s at 37°C). Total motility (phase contrast), sperm viability (6‐carboxifluorescein diacetate and propidium iodide stain), membrane function (hypo‐osmotic swelling test), acrosome integrity (phase contrast), chromatin condensation (toluidine blue stain) and chromatin susceptibility to acid denaturation (acridine orange stain) were evaluated before and after vitrification and analysed using Friedman's test. In all media, the only seminal parameters that were maintained after vitrification were chromatin condensation and integrity. Vitrification of porcine spermatozoon using cryoloops, both in the presence or absence of cryoprotectants and independent of the warming procedure used, permits conservation of sperm chromatin condensation and integrity. It would be interesting to further verify this by producing porcine embryos using vitrified spermatozoon with intracytoplasmic sperm injection.     

A comparison of acceleromyography and mechanomyography for determination of the dose–response curve of rocuronium in children

In order to compare an acceleromyograph (TOF-Guard^TM) with a mechanomyograph (Grass FT03), the dose–response relationship of rocuronium was simultaneously determined in both arms of 15 children aged 3–11 years during anaesthesia with thiopentone, alfentanil and nitrous oxide. Three subgroups of five children received rocuronium 120, 180 or 240 μg.kg⁻¹ randomly. The effective doses to produce 50% and 95% depression of the first twitch of the train-of-four determined by acceleromyography were 206 and 337 μg.kg⁻¹, respectively, while these values determined by mechanomyography were 151 and 331 μg.kg⁻¹, respectively. The dose–response curve obtained by acceleromyography was steeper and shifted to the right compared with that obtained by mechanomyography (p < 0.0001). The difference between the effective dose producing 50% twitch depression determined by the two devices was highly significant (p < 0.0001). In 13 out of 15 children, the acceleromyograph control train-of-four ratio was significantly greater than unity. Although there was a good correlation ( r  = 0.85) between simultaneous pairs of measurements of neuromuscular block, the acceleromyograph exhibited a bias of −25% relative to the mechanomyograph with wide limits of agreement (−62 to +12%). We conclude that acceleromyographic and mechanomyographic measurements should not be used interchangeably when determining the potency of muscle relaxants.     

Immunoglobulin Class of Antispermatozoal Antibodies from Infertile Men and Inhibition of in vitro Sperm Penetration into Cervical Mucus

The presence of IgG and IgA on motile spermatozoa from normal semen donors and men from infertile couples was studied with mixed antiglobulin reaction (MAR) tests.
The percentage of motile spermatozoa with IgG (IgG MAR%) was found to be related to the circulating antispermatozoal IgG. No direct relation could be detected between the IgG MAR% and the sperm agglutinating activity in seminal plasma (SP) or the percentage of motile spermatozoa showing the shaking phenomenon (S%) in the sperm cervical mucus contact (SCMC) test. The percentage of motile spermatozoa with IgA (IgA MAR%) showed no direct relation to the sperm agglutinating activity in serum and SP, but was roughly proportional with the S%.
It was discerned that the shaking phenomenon in the SCMC test was probably due to presence of IgA on the motile spermatozoa. Previously it had been demonstrated that also the sperm agglutinating activity in SP is caused by IgA that is probably locally produced in the male genital tract. In conclusion it was thought that the reduced ability of penetration into cervical mucus by spermatozoa from infertile men is caused by locally produced IgA.