About
233
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Introduction
BA Augustana College, Sioux Falls, SD. Chem/Biol
Ph.D. U. of Colorado, Boulder, Cell Biology
Postdoct: Institute for Molecular Biophysics, Florida State
Staff Scientist, Union Carbide Res Institute, Tarrytown, NY
Associate Professor, Memorial Sloan Kettering Cancer Center, & Cornell Graduate School of Medical Science, NYC
Distinguished Professor Emeritus, S D State University, Brookings, SD
President and Director, SCSA Diagnostics, Brookings, SD
Education
September 1964 - June 1970
U of Colorado, Florida State University
Field of study
- All graduate, postgraduate and faculty positions had emphasis on DNA / chromatin structure and extentive use of flow cytometry
Publications
Publications (233)
The Sperm Chromatin Structure Assay (SCSA®) is a federally registered protocol for simultaneous flow cytometric measures of sperm DNA integrity and chromatin structure. Fresh or frozen/thawed raw semen samples are diluted in buffer to a sperm concentration of ∼1–2×106 /ml and then treated with a pH 1.20 buffer for 30 s to open the DNA strands at si...
Semen analysis is the first, and frequently, the only step in the evaluation of male fertility. Although the laboratory procedures are conducted according to the World Health Organization (WHO) guidelines, semen analysis and especially sperm morphology assessment is very difficult to standardize and obtain reproducible results. This is mainly due t...
Retrograde ejaculation (RE) is a condition defined as the backward flow of the semen during ejaculation, and when present
can result in male infertility. RE may be partial or complete, resulting in either low seminal volume or complete absence of
the ejaculate (dry ejaculate). RE can result from anatomic, neurological or pharmacological conditions....
Sperm DNA fragmentation (SDF) is implicated in male infertility and adverse reproductive outcomes. With the publication of
many studies regarding the etiologies and contributors to SDF, as well as the effects of SDF, guidelines are necessary to aid
clinicians in the application of SDF for male fertility evaluation. Two recent clinical practice guid...
Objective
To determine relationships between age of men with potential male factor infertility and sperm chromatin structure assay (SCSA) measures of sperm DNA fragmentation (SDF) and high DNA stainable sperm (HDS), and to compare these data with those obtained from healthy donor men without reproductive issues.
Design
Retrospective study.
Settin...
Cryopreservation processes can damage spermatozoa and impair structural and functional cell characteristics. Plasma, nuclear membranes, and cellular organelles can suffer from the freeze and thaw process. This study evaluates the protective and stimulant effect of melatonin and caffeine supplementation on the functional characteristics of human spe...
Despite advances in the field of male reproductive health, idiopathic male infertility, in which a man has altered semen
characteristics without an identifiable cause and there is no female factor infertility, remains a challenging condition to diagnose
and manage. Increasing evidence suggests that oxidative stress (OS) plays an independent role in...
Objective
To determine if the high DNA stainability index (HDS), as measured by the sperm chromatin structure assay (SCSA®), is associated with in vitro embryo development and concurrent assisted reproductive technology (ART) outcomes.
Design
A retrospective IRB approved, chart review of patients who completed at least one ART cycle (in vitro fert...
Despite advances in the field of male reproductive health, idiopathic male infertility, in which a man has altered semen characteristics without an identifiable cause and there is no female factor infertility, remains a challenging condition to diag- nose and manage. Increasing evidence suggests that oxidative stress (OS) plays an independent role...
The diagnosis of sperm DNA integrity is increasingly recognized as being crucial to inform the clinical course in infertile couples. An internationally accepted sperm DNA fragmentation assay that determines the proportion of sperm and degree of broken sperm nuclear DNA with recognised clinical thresholds for identifying men at risk of infertility i...
Objective:
To determine whether high DNA stainability (HDS), as assessed by the sperm chromatin structure assay (SCSA), predicts the risk of early miscarriage after in vitro fertilization with intracytoplasmic sperm injection (IVF-ICSI).
Design:
Retrospective cohort study of consecutive pregnancies after IVF and ICSI treatment.
Setting:
Reprod...
Many international toxicology and fertility studies confirm that the "Gold Standard" sperm chromatin structure assay (SCSA) is the most rapid, technician-friendly, and statistically robust test on 5000 sperm/semen samples to determine whether any suspected toxicant is causing sperm DNA damage. Even though the exact causes and origin of sperm DNA da...
The Sperm Chromatin Structure Assay (SCSA ®) is the pioneering sperm DNA fragmentation assay that precisely measures the percent of sperm in a semen sample that have Sperm DNA Damage (SDD), a negative factor for successful pregnancy. The SCSA ® is a rapid, dual parameter, computer driven assay with diligent unbiased flow cytometer measurements on f...
Thirty-five years ago the pioneering paper in Science (240:1131) on the relationship between sperm DNA integrity and pregnancy outcome was featured as the cover issue showing a fluorescence photomicrograph of red and green stained sperm. The flow cytometry data showed a very significant difference in sperm DNA integrity between fertile and subferti...
Study question:
Do the luminal fluids of the epididymis and the vas deferens contribute to sperm chromatin fragmentation (SCF) in mice?
Summary answer:
The luminal fluids of both organs are required for activating SCF in mice, but the vas deferens luminal fluid does this more efficiently than that of the epididymis.
What is known already:
Mice...
The testis of a fertile mammal is characterized by the rapid proliferation of germ cells that undergo unique and complex patterns of differentiation. Testicular tissue is easily dissociated into a cellular suspension that is readily amenable to flow cytometry (FCM) studies. This chapter describes the dual-parameter (DNA, RNA) FCM measurements of ac...
According to worldwide statistics, between one in four and one in five couples have fertility problems. These problems are equally distributed between males and females. Modern lifestyle has obviously increased these problems: endocrine-disrupting chemicals, such as plastic polymer catalysts, alkylphenols, phthalates and so on, and cosmetic additiv...
Sperm DNA damage is a useful biomarker for male infertility diagnosis and prediction of assisted reproduction outcomes. It is associated with reduced fertilization rates, embryo quality and pregnancy rates, and higher rates of spontaneous miscarriage and childhood diseases. This review provides a synopsis of the most recent studies from each of the...
The SCSA(®) is the pioneering assay for the detection of damaged sperm DNA and altered proteins in sperm nuclei via flow cytometry of acridine orange (AO) stained sperm. The SCSA(®) is considered to be the most precise and repeatable test providing very unique, dual parameter data (red vs. green fluorescence) on a 1,024 × 1,024 channel scale, not o...
The SCSA ® is the pioneering assay for the detection of damaged sperm DNA and altered proteins in sperm nuclei via fl ow cytometry of acridine orange (AO) stained sperm. The SCSA ® is considered to be the most precise and repeatable test providing very unique, dual parameter data (red vs. green fl uorescence) on a 1,024 × 1,024 channel scale, not o...
Male factor is now considered to be the cause of nearly half of cases of couple infertility. The classical semen parameters of sperm count, morphology, and motility significantly vary over time and are considered to be poor predictors of pregnancy outcome. In sharp contrast, the sperm chromatin structure assay (SCSA®), which measures sperm DNA frag...
The SCSA® is one of the most widely utilized tests of sperm DNA damage. There are now a number of commercial kits available for testing
of sperm DNA fragmentation in which great variations of clinical thresholds exist both within the same test and between tests.
This presents a real problem for the clinics in providing a correct diagnosis and progn...
Fresh or frozen semen/sperm thawed in a 37°C water bath and diluted to 1–2 × 106 sperm/ml with TNE buffer:
Honeylocust trees (Gleditsiatriacanthos L.) are distributed across a wide range of climatic and edaphic conditions, demonstrating considerable variation in cold, drought, and salinity tolerances. In many angiosperm species, an evolutionary change in nuclear DNA content accompanies colonization into more stressful environments. Fresh leaf nuclei wer...
Inbreeding is known to cause deleterious effects upon reproduction and survival, but its effects upon sperm DNA integrity have not been examined. In the present study, we analyzed this relationship among three endangered ungulates: Gazella cuvieri, Gazella dama mhorr, and Gazella dorcas neglecta. In addition, we examined whether levels of sperm DNA...
Understanding which factors influence offspring mortality rates is a major challenge since it influences population dynamics and may constrain the chances of recovery among endangered species. Most studies have focused on the effects of maternal and environmental factors, but little is known about paternal factors. Among most polygynous mammals, ma...
Men diagnosed with malignancy are often referred for semen banking to preserve their fertility prior to cancer treatment. The chances of cancer patients for achieving future fecundity will be determined by the sperm quality including the integrity of the genomic material in the frozen samples. The objectives of this study were to compare the sperm...
Biological samples, including cryopreserved sperm, are routinely X-rayed during air shipment. The goal was to investigate the impact of X-irradiation used for checked and carry-on luggage on bovine sperm chromatin integrity and postfertilization in vitro embryonic development. Frozen domestic bull sperm (Bos taurus) (n=9 bulls) stored in a dry ship...
Little information exists about boar sperm chromatin quality and fertility within a commercial setting. The objective of this report is to provide information about boar sperm chromatin integrity and its relationship to fertility. The sperm chromatin structure assay (SCSA) was used retrospectively to characterize sperm from 18 sexually mature boars...
Biological samples, including cryopreserved sperm, are routinely shipped using air transportation, in dry shippers that are x-rayed along with routine baggage. Accordingly, it is important to demonstrate that there are no potential risks associated with semen transport. The goal of this study was to investigate the impact of airport radiation used...
The sperm chromatin structure assay (SCSA) was used retrospectively to characterize sperm from 18 sexually mature boars having fertility information. Boar fertility was defined by farrowing rate (FR) and average total number of pigs born (ANB) per litter of gilts and sows mated to individual boars. The SCSA uses flow cytometry to evaluate the struc...
The 2006 American Society for Reproductive Medicine Compendium of Practice Report found no significant effects of elevated sperm DNA fragmentation by using a 30% DNA fragmentation index (DFI) threshold for natural fertilization and SCSA data (odds ratio, 1.07; 95% confidence interval, 0.39-2.93). In contrast, it is shown in this article that these...
To evaluate the effect of vaginal lubricants Pre-Seed, FemGlide, Astroglide, and Replens on human sperm motility and chromatin integrity.
Prospective, comparative, in vitro study.
Andrology laboratory at tertiary care hospital.
Thirteen normozoospermic donors.
Semen samples from 13 subjects were incubated in human tubal fluid media (HTF) controls a...
Previous studies have provided evidence for an association between exposure to high levels of air pollution and increased DNA damage in human sperm. In these studies DNA damage was measured using the sperm chromatin structure assay (SCSA) wherein the percentage of sperm with abnormal chromatin/fragmented DNA is determined and expressed as % DNA fra...
To measure sperm DNA integrity values before and after varicocelectomy in patients with elevated preoperative levels of sperm DNA fragmentation.
Retrospective.
Private urology clinic.
Eleven patients with grade 1, 2, or 3 varicocele.
Varicocelectomy.
Sperm DNA fragmentation values were assessed before and after varicocelectomy.
Ninety percent of th...
The goal of a rapid, precise and objective sperm measure of sperm DNA fragmentation, in situ, was realised a quarter century ago by the pioneer development of the sperm chromatin structure assay (SCSA). Since then, measurements on many thousands of sperm samples from a variety of animals and humans exposed to reproductive toxicants and having diffe...
The effect of environmental pollution on reproductive outcomes has been studied in the context of an inter-disciplinary research program analyzing the impact of air pollution on human health in the Czech Republic.
Semen quality was evaluated in young men living in the Teplice District of Northern Bohemia where they are exposed to episodes of high a...
The issue of male germ line mutagenesis and the effects on developmental defects in the next generation has become increasingly high profile over recent years. Mutations are thought to be becoming more prevalent as a result of: exposure to chemicals in the environment, anti cancer regimes that use genotoxic agents and assisted conception techniques...
Although delaying fatherhood has become somewhat more popular, the heritable sequelae of this practice are not well understood. Advancing paternal age has, however, been implicated in numerous abnormal reproductive and genetic outcomes, including poorer semen quality, reduced fertility, and more frequent spontaneous abortions, as well as some 20 au...
Objective: The integrity and maturity of the paternal genome is an absolute prerequisite for successful fertilization and a healthy offspring. In human spermatozoa, the relationship between apoptosis and the nuclear status remains unclear. Externalization of phosphatidylserine (PS), to the outer sperm membrane leaflet is considered to mark terminal...
This study compares the relative effects of advancing male age on multiple genomic defects in human sperm [DNA fragmentation index (DFI), chromatin integrity, gene mutations, and numerical chromosomal abnormalities], characterizes the relationships among these defects and with semen quality, and estimates the incidence of susceptible individuals fo...
Meta-analyses were conducted to investigate the relationship of sperm DNA fragmentation on pregnancy outcome using in-vivo fertilization, IUI, routine IVF and ICSI. Couples with no known infertility problems were 7.0 times (CI 3.17, 17.7) more likely to achieve a pregnancy/delivery if the DNA fragmentation index (DFI) was <30% (n = 362, P = 0.0001)...
Over the past 25 years, various methods have been developed to measure sperm DNA strand breaks in situ. Currently, there are four major tests of sperm DNA fragmentation, including the Comet, Tunel, sperm chromatin structure assay (SCSA) and the acridine orange test (AOT). The Comet assay is a light microscope technique where the sperm cells are mix...
Over the past decade, several techniques have emerged as potential protocols for evaluating the sperm chromatin integrity. Such integrity is of utmost importance for successful fertilization. Most of the techniques used for sperm chromatin evaluation require extensive instrumentation and special expertise. Toluidine blue (TB) test has been reported...
The integrity and maturity of the paternal genome is an absolute prerequisite for successful fertilization and a healthy offspring. In human spermatozoa, the relationship between apoptosis and the nuclear status remains unclear. Externalization of phosphatidylserine (PS), to the outer sperm membrane leaflet is considered to mark terminal apoptosis....
Flow cytometry was utilised for the first time to independently measure five sperm parameters of individual spermatozoa of bull ejaculates to differentiate between outcome successes after artificial insemination (AI). These parameters included plasma membrane and acrosome integrity, mitochondrial functionality and DNA damage measured by sperm chrom...
The Halosperm test kit, the latest of the sperm DNA fragmentation tests, is considered by Fernández et al. to be a suitable replacement for the Sperm Chromatin Structure Assay (SCSA) test. Although the test is ingenious and interesting, the data lack the statistical rigor of the SCSA test.
This study examined potential associations between exposure to episodes of air pollution and alterations in semen quality. The air pollution, resulting from combustion of coal for industry and home heating in the Teplice district of the Czech Republic, was much higher during the winter than at other times of year with peaks exceeding US air quality...
Studies over the past two decades have clearly shown that reproductive toxicants cause sperm DNA fragmentation. This DNA fragmentation can usually be detected prior to observing alterations of metaphase chromosomes in embryos. Thus, Sperm Chromatin Structure Assay (SCSA)-detected DNA damage is viewed as the molecular precursor to later gross chromo...
Oxidative stress is detrimental to sperm function and a significant factor in the etiology of male infertility. This report examines the association between dietary and supplementary intake of the antioxidants vitamin C, vitamin E, and beta-carotene and sperm chromatin integrity. Eighty-seven healthy male volunteers donated semen samples, completed...
Sperm DNA integrity is obviously important for normal embryo development and pregnancy outcome. Over the past 25 years, various methods have been developed to measure sperm DNA strand breaks in situ. The Sperm Chromatin Structure Assay (SCSA) treats sperm with low pH to denature DNA at the sites of DNA strand breaks, followed by acridine orange (AO...
We examined the genetic composition, habitat use, and morphological variation of a Phoxinus eos-neogaeus unisexual hybrid complex and its sexually reproducing progenitor species inhabiting beaver-modified drainages of Voyageurs National Park, Minnesota. In addition to the single diploid P. eos-neogaeus gynogenetic clone, triploid and diploid-triplo...
To determine the relationship between sperm chromatin structure assay (SCSA) parameters (DNA fragmentation index [DFI] and high DNA stainability [HDS]), and conventional IVF and IVF/intracytoplasmic sperm injection (ICSI) outcomes.
Retrospective review and prospective study.
Private IVF clinic.
Two hundred forty-nine couples undergoing first IVF an...
The health safety of Bt (Bacillus thuringiensis) corn (Zea mays L.) was studied using mouse testes as a sensitive biomonitor of potential toxic effects. Pregnant mice were fed a Bt corn or a nontransgenic (conventional) diet during gestation and lactation. After they were weaned, young male mice were maintained on the respective diets. At 8, 16, 26...
A cryopreserved sperm sample with a low level of DNA fragmentation was used for intracytoplasmic sperm injection and resulted in a twin birth from a couple with a 10-year history of idiopathic infertility.
The health safety of transgenic soybeans (glyphosate-tolerant or Roundup Ready) was studied using the mammalian testis (mouse model) as a sensitive biomonitor of potential toxic effects. Pregnant mice were fed a transgenic soybean or a non-transgenic (conventional) diet through gestation and lactation. After weaning, the young male mice were mainta...
Teratospermia (>60% of morphologically abnormal spermatozoa) is well documented in felids. Even morphologically normal spermatozoa from teratospermic ejaculates have reduced ability to undergo tyrosine phosphorylation, acrosome react, and bind and penetrate oocytes compared with normospermic (<40% abnormal spermatozoa) counterparts. However, it is...