Search PubMed⌕ Search

Biomedical subjects

A Makler

Publications and source records attributed to A Makler.

At least 19 recordsLinked to original sources
PubMed2001

A new objective method for scoring human sperm hyperactivation based on head axis angle deviation.

The aims of the present study were, first to develop a new method for evaluating sperm hyperactivation (HA) based on sperm head axis angle deviation, and second to apply this method in scoring selected sperm populations during capacitation. This was made possible by improving our original superimposed image analysis system (SIAS). The new option on the system enables us to determine the real angular deviation of the entire head in successive superimposed frames. The entire procedure for each spermatozoon requires 10-20 sec, according to the frame/rate utilized. A clear cut-off between the values of hyperactivated, transitional and non-hyperactivated spermatozoa was found at 11 and 21 frames/sec. However, at 6 frames/sec, a partial overlap between the three classes was found. We defined sperm activity as follows. At 11 frames/sec, hyperactivated: angle sum > or = 405 degrees; transitional: 200 degrees < or = angle sum < 405 degrees. At 21 frames/sec, hyperactivated: angle sum > or = 760 degrees; transitional: 350 degrees < or = angle sum < 760 degrees. The results, in agreement with previous research, show the peaks of activity at 3 h, dropping to a minimum at 6 h. This phenomenon was significantly more evident in fertile compared with subfertile semen samples.

Humans↗
PubMed1999

Evaluation of the SQA IIB: a new version of a sperm quality analyzer.

OBJECTIVE: To evaluate the SQA IIB (Sperm Quality Analyzer; MES-Medical Electronic Systems, Migdal Haemek, Israel), sperm analyzer that claims to read the three main sperm indices through algorithmic means and without a microscope. DESIGN: Controlled laboratory study comparing two methods of sperm analysis. SETTING: Academic environment. PATIENT(S): Twenty-six healthy volunteers. INTERVENTION(S): Samples from intact or manipulated specimens were analyzed with the standards of the World Health Organization and the SQA IIB. MAIN OUTCOME MEASURE(S): Results by the two methods were compared and evaluated statistically. RESULT(S): Values from the SQA IIB deviated significantly from those obtained by the standard method for all three indices. Disagreement was more than twofold in 53% and more than threefold in 33% of cases. In specimens with <8% motility or total lack of motility, the SQA IIB showed zero concentration, zero motility, and no normal forms. CONCLUSION(S): Analysis of the three main sperm indices by the SQA IIB is of limited accuracy and reliability. The principle of an indirect evaluation through algorithmic means is inadequate. Because it may furnish misleading information, which is sometimes crucial for the treated couple, it is not suitable for screening and cannot be recommended for clinics, sperm banks, or research studies in andrology.

Algorithms↗
PubMed1998

Dynamic aspects concerned with the mechanism of separating motile sperm from nonmotile sperm, leukocytes, and debris with the use of high-density Percoll gradients.

OBJECTIVE: To investigate the dynamics and the efficacy of separating motile from nonmotile sperm with the use of Percoll gradients as a function of centrifugation time. DESIGN: In vitro laboratory experiments on human sperm. SETTING: Male Infertility Institute. PATIENT(S): Fresh sperm specimens collected from donors and patients. INTERVENTION(S): Aliquots of sperm specimens, spread on top of 40% and 80% Percoll layers in test tubes, were centrifuged for 5-60 minutes. MAIN OUTCOME MEASURE(S): After centrifugation, samples were aspirated from the bottom, interface, and top layers for microscopic analysis. RESULT(S): Within 5 minutes, only fast-moving sperm reached the bottom as a result of both centrifugation force and their own tail movements. From 10 minutes onward, nonmotile sperm, slowed down by Percoll, joined them and gradually reversed the separation process. Leukocytes, debris, and abnormal sperm remained in the upper levels and never reached the bottom. CONCLUSION(S): Separation of motile sperm with the use of Percoll gradients is strongly dependent on centrifugation time. The separation is the gap formed between down-swimming sperm, accelerated by centrifugation, and nonmotile sperm, decelerated by Percoll. This gap gradually disappears with extended spinning.

Cell Separation↗
PubMed1996

Clinical, biochemical, and genetic findings in a large pedigree of male and female patients with 5 alpha-reductase 2 deficiency.

The present report describes a cluster of eight patients with male pseudohermaphroditism from a large pedigree with steroid 5 alpha-reductase 2 deficiency (5 alpha RD), who reside in Southern Lebanon. They were born with unambiguous female external genitalia and reared as girls until puberty, when masculinization occurred, followed by a change of gender role. Semen analysis and testicular histology revealed maturation arrest of spermatogenesis, with low sperm count and motility. Determination of urinary 5 alpha- and 5 beta-reduced adrenal steroids enabled us to diagnose the disease in a male patient with the full-blown clinical syndrome, in another male patient who had undergone bilateral orchidectomy, and in three female individuals with the biochemical derangement. The female patients were unique in this family with respect to their low degree of virilization, but had normal menstrual cycles. Molecular genetic studies were performed on DNA extracted from peripheral leukocytes and from cultured genital skin fibroblasts. The coding sequence of the 5 alpha R2 gene (SRD5A2) was studied by exon-specific PCR, single strand conformation polymorphism, and direct sequencing. A homozygous point mutation was identified in exon 1, leading to a thymidine for adenine substitution, predicting amino acid substitution of leucine for glutamine at position 55.

Adolescent↗
PubMed1995

Evaluating the accuracy of different sperm counting chambers by performing strict counts of photographed beads.

PURPOSE: To suggest a method for evaluating the accuracy of different kinds of sperm counting chambers by eliminating errors concerned with human skills or semen properties. In this method, various concentrations were prepared from stocks of commercially available latex beads (Accu-beads, Hamilton-Thorn Research, Beverly, MA). Samples from identical preparations were loaded into different types of chambers, namely, hemocytometer (Neubauer, improved double, Superior Ltd, Germany), Makler (Sefi Medical Instruments, Haifa, Israel) and Horwell (Horwell Ltd, London, UK). Beads were counted by both direct microscopic observations and by strict scanning of their photographed images. RESULTS: In all cases, counts by direct observation were about 5% higher than strict counts of the same photographed beads. Counting photographed beads showed high reproducibility (average CV of 5.1%) between samples in the two wells of the hemocytometer. Counts of photographed beads, sampled from identical stocks, were on average slightly lower in the Makler chamber (20.7 x 10(6)/ml) and much higher in the Horwell chamber (47.4 x 10(6)/ml) than counts in the hemocytometer (21.5 x 10(6)/ml). Samples from three different batches of Accubeads revealed slight variation in counts between the batches and an average concentration of 11% above the number indicated on the commercial product. CONCLUSIONS; A technique that combined loading latex beads from identical stock into various chambers, proper covering of the tested samples and strict counting of photographed beads provided precise and reproducible results. By eliminating most errors related to human skills and semen properties, this method is suitable for evaluating the accuracy of counting chambers.

Equipment Design↗
PubMed1995

Inability of human sperm to change their orientation in response to external chemical stimuli.

OBJECTIVE: To investigate whether human sperm can respond to external chemical stimuli by orienting themselves toward chemoattractants or withdrawing from hostile environments. DESIGN: Controlled laboratory assays. SETTING: Normal human sperm and two other flagellated micro-organisms were exposed to various potential chemoattractant or chemorepellent substances. INTERVENTION: Human sperm, Euglena viridis, and Escherichia coli were exposed to various substances from the female reproductive system or to various toxic agents by placing them within tiny wells in a sealed minichamber. They were followed by microscopic observation and by intermittent photography. MAIN OUTCOME MEASURE: Images of photographed micro-organisms were analyzed for signs of attraction to or withdrawal from the test substances. RESULTS: Human sperm neither changed their orientation toward nor accumulated next to the well that contained cervical mucus, uterine cavity and follicular fluid, cumulus cells, or intact nonfertilized human eggs. Contrary to other micro-organisms that turned away from sources of hydrochloric acid, sodium hydroxide, ethanol, or glutaraldehyde, human sperm did not withdraw from these solutions. They swam along the ascending chemical gradient, facing ahead while becoming immobilized by these agents. CONCLUSION: It may be implied from the observation that they did not turn away from a hostile environment when expected to do so or turn toward chemoattractants that human sperm do not respond to external chemical stimuli and, most probably, chemotaxis between human sperm and ova in nature does not exist.

Animals↗
PubMed1994

Chemotaxis and chemokinesis of human spermatozoa to follicular factors.

Human spermatozoa accumulate in vitro in diluted follicular fluids obtained from follicles from which the eggs have been fertilized. Using capillary assays under a variety of experimental conditions (ascending or descending gradients of follicular fluid, or no gradient at all) and microscopic assays in which individual spermatozoa could be followed, we found that the sperm accumulation in follicular fluid was the result of both sperm chemotaxis and chemokinesis and eventually hyperactivation-like motility. We determined the optimal conditions for sperm accumulation, which involved sperm preincubation (possibly to induce sperm capacitation) and proper dilution of follicular fluid. In all the assays, the net accumulation was low, probably reflecting the chemotactic responsiveness of only a small fraction of the sperm population at any given time. We partially fractionated follicular fluid in a Centricon microconcentrator (Amicon, Danvers, MA) and by acetone precipitation, and found that at least one of the chemotactic factors is a small (< 10-kDa) molecule that is probably nonhydrophobic. This is the first time that sperm chemotaxis and chemokinesis in response to a follicular factor(s) in mammals has been established and has been distinguished from other processes that might cause sperm accumulation. The physiological significance of these findings is discussed.

Capillary Action↗
PubMed1994

Sequential acquisition of chemotactic responsiveness by human spermatozoa.

Recent studies have indicated that human spermatozoa respond to follicular fluid by attraction to chemotactic factor(s) in the fluid, accompanied by enhancement of motility and ultimately hyperactivation. In this study, we quantified the sperm response. We exposed spermatozoa to a gradient of a chemotactically active fraction of follicular fluid (denoted as "the attractant") and separated the spermatozoa that accumulated in the attractant and those that did not. We thus obtained two subpopulations: one enriched with chemotactically responsive spermatozoa, and one deficient in such spermatozoa. The fraction of the responsive spermatozoa out of the total sperm population was 2-12% at any measured time point. With time, the responsive spermatozoa lost their ability to be attracted, while such activity was gradually acquired by the subpopulation originally deficient in responsive spermatozoa. These results indicate that the identity of responsive spermatozoa is continuously changing. If the in vitro results are representative of the physiological conditions in vivo, they imply that the role of sperm chemotaxis combined with enhanced motility may be to select capacitated spermatozoa and bring them to the egg. Such a mechanism may, over an extended period of time, increase the prospect that an egg will meet capacitated spermatozoa as soon as it ovulates.

Cell Separation↗
PubMed1993

Atrial natriuretic peptide attracts human spermatozoa in vitro.

Here we report that atrial natriuretic peptide (ANP), a known activator of particulate guanylate cyclase, induces attraction and swimming speed enhancement of human spermatozoa in vitro. Using capillary assays under a variety of experimental conditions (ascending or descending gradients of ANP, or no gradient at all) and microscopic assays in which individual spermatozoa could be followed, we found that spermatozoa followed the gradient of ANP and accumulated in it. Speed enhancement was detected in the presence of ANP without a gradient. These observations suggest either that an ANP-like substance is the physiological attractant for human spermatozoa, or, more likely, that ANP directly affects guanylate cyclase in a manner similar to that caused by the physiological attractant.

Atrial Natriuretic Factor↗
PubMed1993

Use of a sealed minichamber for direct observation and evaluation of the in vitro effect of cigarette smoke on sperm motility.

OBJECTIVE: To determine the in vitro effect of cigarette smoke on sperm motility and survival in an attempt to find a possible association with clinical studies that had pointed to the existence of such an effect in vivo. DESIGN: Laboratory experiments in which the effect of cigarette smoke on human sperm placed in a sealed minichamber was directly observed and determined by motion analysis. PATIENTS: High-quality fresh semen specimens were obtained from healthy donors and used for the experimental studies. INTERVENTIONS: Various doses of filtered and nonfiltered cigarette smoke, collected by an improvised manual smoking machine, were streamed at a rate of 2 mL/s into sealed chambers containing samples of washed spermatozoa. Evaluation of the changes in sperm motility was performed in real time by direct microscopical observation and repeated determinations by the multiple exposure photography technique until their complete immobilization. RESULTS: Streaming of 100 mL of cigarette smoke induced a dramatic drop in sperm motility, which caused sperm immobilization in about 15 minutes. This effect showed a clear dose-response relationship either with the amounts streamed or with the time during which sperm were exposed to cigarette smoke. The harmful effect was almost the same whether sperm were exposed to filtered or nonfiltered cigarette smoke. The role of carbon monoxide and hydrogen cyanide on these findings was studied separately, and it was shown that the inhibitory effect was not due to the presence of these two important components of cigarette smoke. CONCLUSIONS: The clear evidence of the in vitro harmful effect of crude cigarette smoke on sperm motility points to the possibility that in heavy smokers certain toxic agents may reach mature spermatozoa or their precursors via the blood stream and induce their harmful effect on sperm motility in vivo.

Carbon Monoxide↗
PubMed1993

Premature ovarian failure--the prognostic application of autoimmunity on conception after ovulation induction.

OBJECTIVE: To assess whether the presence of autoimmune activity in patients with premature ovarian failure (POF) can predict the response to ovulation induction and conception. DESIGN: Assessment of autoimmune activity in patients with POF, correlating the response to ovulation induction with this autoreactivity. SETTING: Tertiary care academic center. PATIENTS: Forty women with POF, 15 of them treated by ovulation induction because of infertility. INTERVENTIONS: All patients were tested for the presence of autoimmune activity, antibodies against various tissues, and 15 of them were treated with combinations of hMG/hCG, glucocorticosteroids as immunosuppressant, and some of them also with a long-acting GnRH agonist. Those patients not interested in infertility were put on hormone replacement therapy (HRT). MAIN OUTCOME MEASURES: Serum E2 and P were measured during ovulation induction as well as follicular diameter monitoring by transvaginal sonography. Achievement of gestations and their outcome were monitored in the group in which ovulation induction was accomplished. RESULTS: Antibodies against thyroglobulin, nuclear antigens, heart, tissue gluten, or increased levels of immunoglobulin (Ig)M, or decreased levels of complement C3 and C4 were significantly different in the patients with POF than in the control population. Autoreactivity of at least one class of the tested antibodies was found in 31 of 40 patients (77%). In 15 patients with autoimmune activity who have undergone ovulation induction using hMG/hCG, 14 pregnancies were achieved in 8 patients. Two of the pregnancies were spontaneous, and 12 were generated by hMG/hCG and fluocortolone, with or without pretreatment with GnRH-a. Twelve healthy babies were generated by 10 gestations, 3 ended in spontaneous abortions (23%), and 1 is ongoing. All the nonspontaneous pregnancies were achieved in the first three cycles of ovulation induction. CONCLUSIONS: Patients with POF and autoimmune activity, suggesting an autoimmune etiology to the ovarian failure, may respond to ovulation induction and have a conception rate of approximately 40% in three cycles. Those who do not conceive in three treatment cycles have a very low probability to conceive; therefore, further attempts of ovulation induction should be discouraged. However, some patients may spontaneously conceive in association with HRT.

Adult↗
PubMed1993

Investigation in real time of the effect of gravitation on human spermatozoa and their tendency to swim-up and swim-down.

To investigate in real time if and how natural gravity affects rates of swim-up and swim-down of human spermatozoa, samples of motile or immobilized spermatozoa in a sealed mini-chamber were placed vertically on a 90 degrees tilted microscope. The mode of their sedimentation, as well as the difference in the rate of their swimming up and down, were observed directly over 30 min and analysed from photomicrographs. Under the influence of natural gravity force, most immobilized spermatozoa turned their heads down in about 5 min and then sank slowly at an average speed of 0.2 mu/s. The number of motile spermatozoa that swam down was 5-6 times more than those swimming up. It can be implied that in spite of the mild force exerted by 1 g on suspended spermatozoa in comparison to the high g force obtained by centrifugation, the overall effect of gravity on the rate of swimming up or down becomes dominant. Gravity causes the sperm heads to turn downward after which the oriented spermatozoa continue to move down by their own tail movements, causing accumulation of motile spermatozoa at the bottom. This may explain why in some recent studies swim-down was superior to the swim-up procedure during sperm separation by self-migration.

Gravitation↗
PubMed1992

A new model for investigating in real-time the existence of chemotaxis in human spermatozoa.

OBJECTIVE: To suggest a new approach to the research of chemotaxis between various media and human spermatozoa to solve the riddle of its existence. DESIGN: Laboratory experiments in which chemotaxis between human spermatozoa and follicular fluid (FF) as well as N-formyl was investigated. SETTING: Male physiology laboratory and in vitro fertilization program unit. PATIENTS: Follicular fluid was collected from 15 patients and used either fresh or after storage at -5 degrees C for less than 2 weeks. High-quality semen specimens were obtained from normal donors and underwent one-step washing with Ham's F-10 solution (Biological Industries, Kibbutz Beth Haemek, Israel). TECHNIQUES: Assays were performed in real time by direct microscopical observation and quantitative determination of the disturbance in random movements of human spermatozoa caused by the tested media. Spermatozoa and tested media, including FF and N-formyl-Met-Leu-Phe were placed in a sealed minichamber and photographed with the aid of the multiple exposure photography technique. RESULTS: By analyzing photographed tracks of more than 80,000 moving spermatozoa, a physiologically insignificant deviation from randomness, corresponding to a 95% confidence interval of -0.57 +/- 0.46%, was found when spermatozoa swam along the concentration gradient of the tested media. The average velocity of spermatozoa swimming toward the test media was slightly lower (less than 5%) than that for spermatozoa swimming away, indicating, if anything, negative chemoattraction. CONCLUSIONS: Despite the high sensitivity of the model, neither natural FF nor synthetic N-formyl exerted any chemotaxis on human sperm. The advantages and potential use of this model for investigating chemotaxis by other biological and synthetic media are discussed.

Body Fluids↗