Biomedical subjects

J H Check

Publications and source records attributed to J H Check.

At least 325 records · Page 18Linked to original sources

PubMedDate not supplied

Failure of the addition of fresh seminal plasma to cryopreserved-thawed sperm to improve semen parameters.

Previous data has shown that subnormal motility in some semen specimens can be improved by the addition of fresh human seminal plasma (HSP). However, if the HSP was first frozen the motility-enhancing factor was lost. We hypothesized that some of the reduction in sperm motility of cryopreserved-thawed sperm may be related to damage of the "motility-enhancing factor" of HSP. This study evaluated whether the addition of fresh HSP could improve the motility of frozen-thawed sperm. Each frozen-thawed specimen was evaluated for motile density and hypoosmotic swelling and then divided into two aliquots. Equal volumes of HSP, human tubal fluid (HTF), and control media were added and the semen parameters were reevaluated. The mean scores for motile density and percent motility did not change compared with baseline thawed volumes with either HSP or HTF additives. There were some isolated cases that did improve with either HSP (21%) or HTF (14%). Future studies are needed to determine whether this improvement is coincidental or consistent, and to determine whether at least some individuals can benefit from the addition of fresh HSP to frozen-thawed sperm.

Cryopreservation↗

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Effect of shortened exposure time to the critical period for ice crystal formation on subsequent post-thaw semen parameters from cryopreserved sperm.

Cryopreservation of human sperm using present methods leads to a reduced fertility potential of the specimen. In many instances this prevents the successful fertilization of the female partner from the frozen-thawed specimens of males whose semen has been cryopreserved prior to surgery, chemo-therapy, or even vasectomy. Furthermore, even though some donor specimens can be successfully used for achieving pregnancies, one needs to place the sperm intrauterine to approach the same pregnancy rates as those of fresh intracervical insemination. The main mechanism considered for sperm damage by cryopreservation is ice crystal formation. The most critical time for forming ice crystals is from 0 to -10 degrees C. In the present study the effect of a modified rapid cryopreservation technique with reduction of exposure time to the 0 to -10 degrees C temperature range was compared to standard freezing procedures on subsequent semen parameters. Though no significant differences were found on post-thaw motile densities or hypoosmotic swelling test scores, a new, equally effective, but more rapid technique for cryopreservation is reported.

Cryopreservation↗

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Effect of clomiphene citrate therapy on postcoital tests in successive treatment cycles including response to supplemental estrogen therapy.

Debate continues as to whether clomiphene citrate (CC) has an adverse effect on cervical mucus. Some researchers conclude that adverse effects maybe related to hormonal abnormalities, e.g., premature luteinization or improper timing. This study evaluated the initial and accumulative effects of CC on postcoital testing (PCT) and attempted to determine if supplemental estrogen (E) improves PCT and/or inhibits follicular maturation. The majority of patients taking CC had poor PCT tests even on the first treatment cycle. Good initial PCTs tended to remain so in subsequent cycles or at least to respond to subsequent supplemental E. Poor PCTs responding to E tended to continue to respond to the combination. PCTs not responding to E therapy continued this pattern in subsequent cycles. Supplemental E did not suppress follicular maturation.

Animals↗

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Single daily monitoring of periovulatory estradiol, progesterone, and luteinizing sera hormone levels in natural cycles useful for timing intrauterine insemination.

Single daily periovulatory serum levels of luteinizing hormone (LH), estradiol (E2), and progesterone (P) may be useful to predict the time of ovulation, since serum P is known to rise to 1000 pg/mL about 24 h after the LH surge. Intrauterine insemination (IUI) was performed based on the serum P level at the time of the LH surge; if sera P measures < 1000 pg/mL, then IUI is performed 36-40 h later; but if P is > or = 1000 pg/mL, IUI is performed 12-20 h later. The relationship of sera LH, E2, and P levels and follicular diameter were evaluated at the time of the LH surge and the day before in 40 women with cervical factor who conceived following a single IUI. If E2 levels were obtained the day before and the day of the LH surge and measured < 200 or > or = 200 pg/mL, a shorter interval for the IUI was suggested. The 27% pregnancy rate/cycle suggests that measurement of single daily periovulatory hormonal levels are useful for precise timing of IUI.

Estradiol↗

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Comparison of direct swim-up, mini-Percoll, and Sephadex G10 separation procedures.

A comparison was made of three sperm separation techniques--direct swim-up, mini-Percoll, and Sephadex G-10--on semen parameters, including count, % motility, forward progression, and hypoosmotic swelling (HOS) test scores. Overall, the best quality sperm (less debris, best % and quality motility, and best HOS scores) were noted with the direct swim-up procedure. Mini-Percoll resulted in the highest count, but the worst HOS score. Sephadex G-10 resulted in quality of semen specimen almost as good as the direct swim-up procedure, but did allow some noncellular debris and bacteria to filter through the column.

Cell Separation↗

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Effect of natural antioxidants tocopherol and ascorbic acids in maintenance of sperm activity during freeze-thaw process.

Excessive generation of reactive oxygen species and increased peroxidation of the phospholipids in the membrane is proposed as a biochemical basis for the reduced activity of spermatozoa in cryopreserved semen. The possible role of alpha-tocopherol (VE) and ascorbic acid (VC) in improving the quality of frozen semen was investigated. Semen samples were divided into aliquots and frozen in freezing media with and without VC or VE. Sperm parameters, including motility after thawing and also at 2 h, % grade A motility (rapid and linear forward progression), and hypoosmotic swelling (HOS) scores, were measured in all samples. Vitamin C did not result in any improvement in sperm parameters studies. Vitamin E improved the post-thaw motility minimally. This improvement, although statistically significant, was actually very small. There were, however, wide variations between the samples. The motility improvement was considered in 5 of 12 samples, and HOS improved in some of the samples tested with VE. Future studies are needed to determine if these antioxidants can produce a consistent improvement in some individuals rather than help the majority of patients.

Antioxidants↗

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Male:female sex ratio in births resulting from IVF according to swim-up versus Percoll preparation of inseminated sperm.

Two centers have independently reported a higher rate of male to female births following insemination of sperm prepared by a modified swim-up technique. The principle of the modified swim-up is that a small percentage of the x-bearing sperm are the fastest and travel to the top of the supernatant, followed by the y-bearing sperm; the bulk of the x-bearing sperm remain in the pellet. In this technique, the very top layer is discarded and the resulting supernatant is collected, leaving only the pellet. In contrast, with the conventional swim-up technique, the entire supernatant is collected. The study presented herein retrospectively evaluated the male to female sex ratio of births from in vitro fertilization using standard swim-up technique and compared these results to the ratio obtained from separating with Percoll. There were 53% male births with swim-up vs. 54% with Percoll in singleton pregnancies and 51% males with swim-up vs. 40% with Percoll with multiple births. Thus, conventional swim-up alone does not increase percentage of male births.

Cell Separation↗

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Failure of test yolk buffer to decrease antisperm antibodies on sperm.

The objective of this study was to evaluate whether the suspension of sperm naturally bound or artificially coated with antisperm antibody (ASA) in test yolk buffer (TYB) will reduce the percentage of sperm positive for ASA. Attempts were made to repeat a study performed by Lam et al., in which they claimed a significant decrease in percentage of sperm positive for both IgA and IgG. Furthermore, the study attempted to determine if this methodology would similarly reduce the percentage of sperm naturally bound with ASA. There was no reduction in postincubation levels in percentage of sperm having attachment of IgA or IgG in either the sperm specimens naturally bound with ASA or donor sperm artificially coated with antibodies. Incubation in TYB does not appear to be an effective method to reduce the percentage of sperm bound with ASA. Possibly, it could reduce the amount of ASA bound to each sperm, but this would have to be proven by other studies.

Antibodies↗

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Cumulus removal and addition of follicular fluid possibly improves pregnancy rates with in vitro fertilization for male factor.

This study evaluated the use of in vitro fertilization (IVF) for patients with subnormal semen parameters without the use of micromanipulation. All patients were characterized as having male factor as follows: normal morphology (NM) < or = 10% according to strict criteria [15] and motile density (MD) < or = 10 x 10(6)/mL. Strict morphology was divided into three groups: group I (n = 72), < or = 2% group II (n = 24), 3-5%; and group III (n = 29), 6-10%. Modification of standard IVF techniques included manual cumulus removal (CR) from oocytes, pooling up to ten oocytes together in 1 mL of media, and supplementing media with 20% human follicular fluid (FF). Rates of fertilization and pregnancy were compared. The overall fertilization rate (FR) was 57.7% and the pregnancy rate (PR) per retrieval cycle was 14.8%. There was no significant improvement in the fertilization or PRs when IVF was modified using CR and FF, although the FR was higher in group I for patients who received the modified procedures. In patients with < or = 5 x 10(6) sperm/mL, there were no pregnancies in five cycles and four transfers following the conventional method, but two sets of twins with the modified protocols in seven cycles. Clinical pregnancies were achieved with male factor without the need for micromanipulation. The most severe cases were automatically assigned to modified IVF techniques, e.g., CR with or without FF. Prospective randomized studies are needed to determine if modified procedures are superior to conventional therapy.

Culture Media↗

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Sera gonadotropins, testosterone, and prolactin levels in men with oligozoospermia or asthenozoospermia.

Many previous studies evaluating various hormone levels in males with subnormal semen analyses were performed when the normal semen parameters were considerably higher than now. This study evaluated sera levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), total testosterone (TET), free TET, and prolactin (PRL) in 60 males with oligospermia and decreased motility according to recent World Health Organization standards. Three separate groups were evaluated: group 1, motile density (MD) < 5 x 10(6)/mL (but not azoospermia); group 2, 5 < or = MD < 10 x 10(6)/mL; group 3, MD > 10 x 10(6)/mL, but % motility < 30%. There were no significant differences in mean FSH levels between groups. Overall FSH was increased in 47.1% of the cases. In contrast, mean LH levels were normal in all three groups. Only 17.3% of the entire group had elevated LH levels. The TET level was below normal in 32.3% of the entire group, with a fairly equal distribution between the three groups. Overall, only 7.8% had elevated PRL levels, with the highest percentage found in group 3 (22.2%). Only a small minority of patients with increased FSH had low TET levels compared to 48.0% of those with normal FSH. These data demonstrate that when using the lower semen parameters, the most common serum hormone abnormality is increased FSH; men with MD < 5 x 10(6)/mL do not have a higher incidence of elevated FSH than those with higher MDs.(ABSTRACT TRUNCATED AT 250 WORDS)

Follicle Stimulating Hormone↗

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Higher pregnancy rates following treatment of cervical factor with intrauterine insemination without superovulation versus intercourse: the importance of a well-timed postcoital test for infertility.

A randomized study comparing the efficacy of timed intrauterine insemination (IUI) without hyperstimulation to sexual intercourse was performed in women with cervical factor infertility. Among the strict requirements for inclusion in the study were a normal semen analysis in the male partner, as well as the failure to demonstrate any sperm with progressive forward motion in a postcoital test performed 8-12 h after intercourse at the time of a mature follicle. All other infertility factors were negative. The data demonstrated a statistically significant fecundity rate at 1 month when IUI was compared to intercourse (21.2 vs. 3.9%). These data suggest that carefully timed IUI in nonhyperstimulated cycles is an effective treatment for cervical factor infertility.

Bromocriptine↗

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Effect of an intermediate hold with vapor freezing on subsequent hypoosmotic swelling in thawed sperm.

Cryopreservation and thawing of sperm exerts an adverse effect on functional integrity of the sperm membrane as measured by the hypoosmotic swelling (HOS) test. Supercooling using the liquid nitrogen (LN2) vapor technique may damage membranes by favoring ice crystal formation. Slight slowing of the cooling process may allow escape of intracellular fluid. This study was conducted to evaluate modification of the LN2 vapor technique by employing an intermediate hold in a freezer (to slow down the rate of cooling) on HOS scores on specimens thawed 1 month after freezing. Semen samples were obtained from male partners of infertile couples with a requirement of a baseline HOS score < 70% but > or = 60%. The HOS test was performed on the unprepared semen sample prior to freezing and immediately post-thaw 1 month later on the aliquot frozen with LN2 vapors only vs. the equal fraction subjected to an intermediate hold. The mean initial HOS score was 68.5% and was 47% in thawed specimens that had been cryopreserved with and without an intermediate hold. There were no differences in the percentage of specimens exhibiting a > 50% HOS score following vapor freeze (70%) or vapor freeze with a hold (74%). Thus, these data do not demonstrate any advantage of slowing the vapor freezing process by utilizing an intermediate hold.

Cell Membrane↗

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Intrauterine insemination for cervical and male factor without superovulation.

Intrauterine insemination (IUI) has been used for the treatment of various causes of infertility, including unexplained infertility, male factor, and cervical factor. Some centers frequently use superovulation combined with IUI. The study presented herein attempted to evaluate the efficacy of IUI without superovulation in cases where all causes of infertility other than cervical or male factors have been eliminated. However, in the case of poor or absent cervical mucus, the use of controlled ovarian hyperstimulation (COH) may obscure the actual importance of the IUI, since it is possible that the poor cervical mucus is related to poor timing, inadequate follicular maturation, or low estradiol levels, which if corrected will obviate the need for IUI. In this study IUI was targeted for 36-40 h following the sera luteinizing hormone surge. A total of 108 patients were enrolled in this study: 47 with male factor, 61 with cervical factor. Patients were followed for a maximum of three cycles unless a pregnancy occurred within 3 months of treatment. Comparison of pregnancy rates (PRs) were based on diagnosis. The cumulative PRs per cycle for each of the three cycles studied were as follows: cervical factor--19.7, 36.8, and 36.8%; male factor--12.8, 29.3, and 38.3%. Thus, PRs were comparable for both groups after three treatment cycles. These data demonstrate that IUI is an effective therapy for cervical and/or male factor, even without superovulation.

Adult↗

PubMedDate not supplied

Effect of pentoxifylline added to freezing media on subsequent post-thaw hypoosmotic swelling test and other semen parameters.

This study evaluated the effects of pentoxifylline (PTX) on post-thaw semen parameters as well as the hypoosmotic swelling (HOS) test. Fourteen samples were evaluated for volume, count, motility, % grade A sperm, and HOS test. Two aliquots were frozen, one in freezing medium and the other in a 3 mM solution of PTX and freezing medium. Both groups were frozen in liquid nitrogen vapors for 30 min. Thawing was performed at 37 degrees C for 15 min, followed by a wash with 2 parts 0.5% HSA/MHTF to 1 part sample. Pellets were resuspended in 0. MHTF and then evaluated as described above. In addition, motility was evaluated 2 h post-thaw. Following freeze-thaw, the mean motile densities were similar (17.5 x 10 motile/mL vs. 20.4 x 10(6) motile/mL for PTX and control, respectively). Two hours post-thaw, the PTX group had a mean sperm motility of 31.3% vs. 37.7% for the control group (p > .05). There were no significant differences in % grade A sperm in PTX (13.0%) vs. control (12.0%). Similarly, HOS scores did not improve following cryopreservation (43.0% and 50.6% for PTX and control, respectively). Thus, no improvement was found by freezing sperm with PTX.

Analysis of Variance↗

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The value of motile density, strict morphology, and the hypoosmotic swelling test in in vitro fertilization-embryo transfer.

This study was conducted to evaluate the effect of a single abnormal semen parameter on subsequent implantation and pregnancy rates (PRs) following in vitro fertilization-embryo transfer (IVF-ET). The parameters evaluated were motile density (MD), strict normal morphology (SNM), and the hypoosmotic swelling (HOS) test. A total of 592 IVF cycles were evaluated. Patients were divided into four groups each with one abnormal semen parameter except for the control: group 1 (n = 509), control group: MD > or = 10 x 10(6)/mL, HOS > or = 50%, SNM > or = 4%; group 2 (n = 51): HOS and SNM normal, MD < 10 x 10(6)/mL; group 3 (n = 14): MD and SNM normal, HOS < 50%; group 4 (n = 18): MD and HOS normal, SNM < 4%. The implantation rate was 10.2% for the control group. The implantation rate was similar for the low MD (9.0%) and the low SNM (16.7%) groups. However, the low HOS group had a significantly lower implantation rate (0%). The clinical PRs are similar in the control group and low MD and SNM groups, but decreased in the low HOS group (21.5, 15.0, 30.8, and 0%, respectively). Ongoing PRs were also similar with the exception of the low HOS group (0%). This comparative study supports previous conclusions that the subnormal HOS test is the best semen parameter available that predicts poor PRs. It also suggests that some qualitative defect in the embryos may result from defective sperm membranes, resulting in an apparently normal appearance but physiologically defective embryo.

Cell Count↗

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Improved results of thawed sperm cryopreserved with slow stage cooling with a cellevator.

There is a need to develop a sperm cryopreservation technique that will allow good pregnancy rates following intrauterine insemination of thawed semen specimens that have been frozen prior to sperm-destructive procedures, such as surgery, chemotherapy, or radiation therapy. A slower cooling rate using a commercial semiprogrammable freezer may provide improved post-thaw motility and hypoosmotic swelling (HOS) test scores. However, the cost of this apparatus precludes it from being used in most andrology centers. This study compares the efficacy of slow stage cooling using an inexpensive cellevator (a device used to freeze lymphocytes) to liquid nitrogen vapor freezing. The semen from 27 males was equally divided and one aliquot was cryopreserved with the cellevator stage cooling and the other with the liquid nitrogen vapor technique. The percent motility and percent grade A sperm post-thaw were significantly higher when cryopreserved with the cellevator than with vapor freezing, as was the mean percentage of sperm showing HOS changes.

Adult↗

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Relationship of subnormal semen parameters and subsequent zona pellucida thinning following in vitro fertilization.

Infertility due to male factor has been associated with reduced implantation rates despite normal fertilization. The mechanism responsible for lower pregnancy rates is not known. One cause of failure to achieve pregnancy despite transfer of embryos is impairment of zona pellucida (ZP) thinning, which inhibits the embryo from hatching despite initial cell cleavage. This study was designed to evaluate whether there is an association between the ability of the ZP to thin, as measured by ZP thickness on day of transfer, and subnormal semen parameters. Significant differences in ZP thickness (p < 0.05, Kruskal-Wallis) were noted according to median concentration of sperm, total motile sperm, and motile density in that these values were the highest in the group of embryos with the thinnest zona pellucida and lowest in the group with the thickest zona pellucida. Thus, some factor may be missing from sperm from subnormal specimens that normally assists in zona thinning.

Adult↗

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A randomized comparison of the effect of two diuretics, a converting enzyme inhibitor, and a sympathomimetic amine on weight loss in diet-refractory patients.

We hypothesized that women refractory to dietary weight loss may have a type of idiopathic edema. In a study of 200 women, we compared four drugs, used previously for treating idiopathic edema, to determine their efficacy in causing weight reduction. After 6 months of treatment, the percentage of treated groups losing at least 10% of baseline weight was 6% for hydrochlorothiazide, 8% for spironolactone, 68% for dextroamphetamine sulfate, and 4% for captopril. The percentage losing >20% and >30% of baseline weight in the same treatment groups was 28% and 10% for dextroamphetamine therapy but 0% for the other three groups. Of the women who failed to lose weight with one of the nonamphetamine therapies during the first 6 months, 132 were then treated with dextroamphetamine; 68% lost =10% of their baseline weight, and 30% and 7% of patients lost =20% and =30%, respectively. With use of the classic definition of idiopathic orthostatic edema (urinary output of <55% of ingested water load in 4 hours), only 58 of the 200 study patients had this diagnosis; however, 144 patients excreted <75% of the load. Comparison of the efficacy of amphetamine therapy in patients with <75% versus =75% urinary excretion showed 120 of 131 (92%) lost =10% in the former category versus only 4 of 51 (8%) in the latter. Of the 58 patients who excreted <55% of the water load, 52 (90%) lost =10% of baseline weight with amphetamine therapy. The patients noted no effects of therapy on dietary consumption. The responsiveness of the patients to amphetamine therapy during the second 6-month period despite failing to lose weight with the three other therapies suggests that no inadvertent bias was present in the randomization process. Thus, the results suggest that some women who are recalcitrant to dietary weight loss may have a mild type of water retention that is refractory to diuretics but responsive to amphetamines.

Clinical Trial↗