Kjersten Larson

DNA damage in patients with untreated cancer as measured by the sperm chromatin structure assay

OBJECTIVE To examine the relationship between sperm chromatin defects, evaluated by sperm chromatin structure assay (SCSA) and semen characteristics in cryopreserved semen specimens from patients diagnosed with various types of cancer. DESIGN Prospective study. SETTING Andrology laboratory at a tertiary care hospital. PATIENT(S) Cryopreserved semen samples from 12 healthy fertile men and 37 men diagnosed with cancer: testicular cancer (n = 20), Hodgkins disease (n = 11), non-Hodgkins disease (n = 4), and other neoplasm (n = 2). INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) The shift of green (native DNA) to red (denatured, single-stranded DNA) fluorescence in acridine orange-stained nuclei was measured and quantified using the expression alpha(t)(red fluorescence/[red + green fluorescence] per cell). Sperm DNA damage was correlated with classical semen characteristics. RESULT(S) Cancer patients as a group had significantly higher DNA damage when compared with controls. Specimens with high COMPalpha(t) values (percentage of sperm with denatured DNA) were present in all groups of cancer patients. No meaningful correlation was seen between the extent of DNA damage and classical semen measures. CONCLUSION(S) DNA damage in spermatozoa is prevalent in the majority of cancer patients. SCSA provides important information about the biochemical integrity of sperm DNA in men with cancer before their treatment.

“Paedocannibal” Morph Barred Tiger Salamanders (Ambystoma tigrinum mavortium) from Eastern South Dakota

Abstract We report characteristics of a previously unknown population of Ambystoma tigrinum mavortium (barred tiger salamander) from eastern South Dakota, a location that extends the formerly known range of this subspecies about 150 km north. This population contains paedotypic animals and a small percentage of cannibal morphs. At least one cannibal morph was paedotypic. The vomerine tooth hypertrophy characteristic of cannibal morphs described here differs from the cannibal morph A. t. tigrinum from nearby (about 160 km) northwestern Iowa; in particular the pair of caudolateral tooth ridges has smaller teeth in individuals from the A. t. mavortium population. The study wetland is located near the convergence of four recognized (pending revision) tiger salamander subspecies (A. t. diaboli and A. t. melanosticum in addition to A. t. mavortium and A. t. tigrinum), making it an excellent region to examine subspecific morphological features in light of shared ecological factors. We suggest creating a formal nomenclatural distinction between cannibal morph larval phenotypes and cannibal morph paedotypic phenotypes.

Negative effects of sperm nuclear DNA damage on the fertility potential of couples with idiopathic and male-factor infertility

FERTILITY POTENTIAL OF COUPLES WITH IDIOPATHIC AND MALE-FACTOR INFERTILITY Ramadan A Saleh, Ashok Agarwal, Cleveland Clinic Foundation, Essam A Nada, South Valley University, Mohamed H El-Tonsy, al-Minya University, Donald P Evenson, Kjersten Larson, South Dakota State University Objective: Rapidly accumulating data, in recent years, indicate that increased sperm DNA damage is detrimental to the fertility potential of men. The objectives of this study were to examine: i) levels of sperm DNA damage in infertile men with idiopathic and male-factor infertility, and ii) the effects of sperm DNA damage on the outcome of assisted reproductive techniques (ART).

Correlation of reactive oxygen species in neat semen with sperm chromatin structure assay-defined sperm DNA damage.

WITH SPERM CHROMATIN STRUCTURE ASSAY-DEFINED SPERM DNA DAMAGE Ramadan A. Saleh, The Cleveland Clinic Foundation, Kjersten L. Larson, South Dakota State University, Rakesh K. Sharma, Anthony J. Thomas, The Cleveland Clinic Foundation, Donald P. Evenson, South Dakota State University, Ashok Agarwal, The Cleveland Clinic Foundation Objective: Artificially induced reactive oxygen species (ROS) has been shown to cause an increase in DNA fragmentation. Increased levels of ROS in neat semen may reflect oxidative stress (OS) status in vivo. The objective of this study was to examine the relationship between ROS levels in neat semen and the susceptibility of sperm chromatin to acid-induced denaturation in situ as measured by sperm chromatin structure assay (SCSA).

Seminal oxidative stress (OS) is highly correlated with sperm DNA damage in men with idiopathic and male-factor infertility

SPERM DNA DAMAGE IN MEN WITH IDIOPATHIC AND MALEFACTOR INFERTILITY Ramadan A Saleh, Ashok Agarwal, Cleveland Clinic Foundation, Essam A Nada, South Valley University, Mohamed H El-Tonsy, al-Minya University, Donald P Evenson, Kjersten Larson, South Dakota State University Objective: Seminal OS is due to an imbalance between reactive oxygen species (ROS) and total antioxidant capacity (TAC) in semen and is involved in many aspects of male infertility. Our group has recently introduced the composite ROS-TAC score as an accurate measure of seminal OS. In this study, we examined the correlation of seminal OS with sperm DNA damage and standard sperm parameters in infertile men with idiopathic and malefactor infertility.