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Anthony J Thomas

Publications and source records attributed to Anthony J Thomas.

At least 19 recordsLinked to original sources
PubMed2004

Cryopreservation and thawing is associated with varying extent of activation of apoptotic machinery in subsets of ejaculated human spermatozoa.

We investigated the impact of cryopreservation and thawing on levels of caspases-3, -8, and -9 activity, intact mitochondrial membrane potential (Deltapsim), and DNA fragmentation in human spermatozoa. Eleven pools of cryopreserved and eight pools of fresh semen samples were examined. Mature and immature fractions were separated on a two-layer density gradient (47% and 90%) and further subdivided based on the externalization of phosphatidylserine and its binding to annexin V-labeled superparamagnetic microbeads (ANMB). Levels of activated caspases were assessed using fluorescein-labeled inhibitors of caspases (FLICA), Deltapsim using a lipophilic cationic dye, and DNA fragmentation by the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. Cryopreservation was significantly associated with activation of caspases-3, -8, and -9, as well as disruption of the mitochondrial membrane potential but no significant changes were observed in DNA fragmentation. In mature sperm, caspase activation was only detected in the ANMB+ fraction, whereas in immature sperm, both ANMB+ and ANMB- fractions showed activated caspase levels. In ANMB+ immature sperm, apoptosis seemed to be triggered by a surface ligand-receptor mechanism as well as by disruption of mitochondria, whereas in ANMB- immature sperm, apoptosis was induced by activation of caspase-9 following loss of intact Deltapsim. These results demonstrate that selection of annexin V-negative mature spermatozoa might be of clinical relevance for fertility preservation, as this sperm fraction shows no activated apoptosis during the cryopreservation process.

Annexin A5↗
PubMed2004

Novel association between sperm reactive oxygen species production, sperm morphological defects, and the sperm deformity index.

OBJECTIVE: To examine the relationship between sperm reactive oxygen species (ROS) production and sperm morphology in a group of infertile men and healthy fertile donors. DESIGN: A prospective clinical study. SETTING: Male infertility clinic, Glickman Urological Institute, The Cleveland Clinic Foundation, Cleveland, Ohio, and the Reproductive Medicine Unit, Liverpool Women's Hospital, United Kingdom PATIENT(S): Thirty-nine infertile men and 13 healthy fertile donors (control). INTERVENTION(S): Standard semen analysis, seminal leukocyte concentration, assessment of sperm morphology, and measurement of sperm ROS production. MAIN OUTCOME MEASURE(S): Levels of sperm ROS production, percentages of different sperm morphological abnormalities, and the sperm deformity index (SDI) scores. RESULT(S): A significant negative correlation was observed between sperm ROS production and the proportion of sperm with normal morphology and borderline morphology. Reactive oxygen species production was positively correlated with the proportion of sperm with amorphous heads, damaged acrosomes, midpiece defects, cytoplasmic droplets, tail defects, and SDI scores. Logistic regression analysis identified a two-variable model including SDI and percentage sperm motility, which correctly identified 84% of individuals with high seminal ROS and 85% of individuals with low seminal ROS. The model had an overall accuracy of 85%. CONCLUSION(S): The standard semen analysis to assess sperm motility, sperm morphology, and the SDI scores is a useful tool in identifying infertile men with high seminal ROS in infertility clinics where facilities for measuring levels of seminal ROS are not available.

Female↗
PubMed2004

Novel associations between specific sperm morphological defects and leukocytospermia.

OBJECTIVE: To examine the relationship between leukocyte concentrations in semen and sperm morphology in a group of infertile men and healthy fertile donors. DESIGN: A prospective clinical study. SETTING: Male infertility clinic at a tertiary care teaching hospital and a reproductive medicine unit at a Women's Hospital in the United Kingdom. PATIENT(S): Fifty-six infertile men and 13 healthy fertile sperm donors (control). INTERVENTION(S): Standard semen analysis, seminal leukocyte concentration, and the assessment of sperm morphology and sperm deformity index (SDI), applying Tygerberg's strict criteria. MAIN OUTCOME MEASURE(S): Granulocyte concentrations in semen, percentages of different sperm morphological abnormalities, and SDI scores. RESULT(S): Leukocyte concentrations were statistically significantly and negatively correlated with the proportion of sperm with damaged acrosomes, cytoplasmic droplet, tail defects, and SDI scores with normal and borderline morphology. The percentage sperm motility was significantly and negatively correlated with leukocytic concentration in semen. However, the leukocytic concentration was not significantly correlated with sperm concentration. CONCLUSION(S): This is the first study to report a significant positive correlation between leukocytospermia and sperm tail defects, acrosomal damage, and high SDI scores. These observations suggest that leukocytospermia is associated with compromised sperm structural integrity.

Acrosome↗
PubMed2004

Human sperm superoxide anion generation and correlation with semen quality in patients with male infertility.

OBJECTIVE: To measure levels of reactive oxygen species (ROS) including H(2)O(2) and O(2)(.-) generation in infertile men and determine whether sperm quality is correlated with levels of ROS triggered by the exogenous reduced form of beta nicotinamide adenine dinucleotide phosphate (NADPH). DESIGN: Prospective study. SETTING: Male infertility clinic at a tertiary healthcare center. PATIENT(S): Eleven infertile men and six healthy donors. INTERVENTION(S): Chemiluminescence assay using luminol and lucigenin as probes before and after incubating sperm samples with 5 mM and 10 mM of NADPH. MAIN OUTCOME MEASURE(S): The ROS generation (10(6) counted photons per minute/10(6) sperm). RESULT(S): Baseline levels of O(2)(.-) generation were significantly higher in the infertile patients than in the healthy donors (r = 0.73, 95% confidence interval [median (25th, 75th percentiles): 0.73 (0.5, 5.5) vs. 0.2 (0.0, 0.5)] when lucigenin was used as the probe. Compared with basal levels, O(2)(.-) generation was significantly higher after coincubation with NADPH (5 mM and 10 mM) in the entire combined study population, and patients only but not donors. The O(2)(.-) generation was negatively correlated with sperm concentration (r = -0.75, 95% CI 0.38-1), motility (r = -0.69, 95% CI 0.28-1), and percentage of normal morphology (r = -0.78, 95% CI 0.36-1). CONCLUSION(S): Spermatozoa from infertile men produce higher levels of O(2)(.-) in the presence of exogenous NADPH compared to healthy donors. The ability of spermatozoa to generate O(2)(.-) increases as the semen quality declines.

Acridines↗
PubMed2004

Increased seminal reactive oxygen species levels in patients with varicoceles correlate with varicocele grade but not with testis size.

Increased levels of reactive oxygen species (ROS) are associated with clinical varicoceles; however, its correlation with varicocele grade and testis size is unknown. In our study, seminal ROS levels showed significant correlation with left varicocele grade and significantly elevated seminal ROS levels were seen in men with left varicocele grade 2 and 3 compared to grade 1.

Adult↗
PubMed2004

Relationship of interleukin-6 with semen characteristics and oxidative stress in patients with varicocele.

OBJECTIVES: To examine levels of interleukin-6 (IL-6) in fertile semen donors and patients with varicocele and examine its association with semen characteristics and levels of reactive oxygen species (ROS). METHODS: We conducted a prospective study consisting of 15 fertile donors (controls) and 35 infertile patients with varicocele. Semen analysis was performed according to the World Health Organization guidelines. IL-6 levels were measured using the enzyme-linked immunosorbent assay. ROS (x10(4) counted photons per minute per 20 x 10(6) sperm) and total antioxidant capacity (molar trolox equivalents) were measured using a chemiluminescence assay. RESULTS: The sperm concentration and motility were significantly greater in the donors compared with the infertile patients with varicocele (P <0.0001 and P = 0.01, respectively). The IL-6 (log10 [IL-6 +1]) and ROS (log10 [ROS +1]) levels were significantly greater in infertile patients with varicocele than in the donors (IL-6: 2.1 [1.7, 2.4] versus 0.7 [0, 1.9], P = 0.003; ROS: 1.8 [1.2, 2.6] versus 1.0 [0.7, 1.6], P = 0.04). The total antioxidant capacity levels were significantly lower in the varicocele patients (1166.7 +/- 366.2) than in the donors (1556.4 +/- 468.1; P = 0.003). The IL-6 levels correlated significantly with the ROS levels in the infertile patients with varicocele (r = -0.39; P = 0.01). CONCLUSIONS: Infertile patients with varicocele exhibited elevated levels of IL-6 and ROS and decreased levels of total antioxidant capacity. Pro-inflammatory cytokine IL-6 and oxidative stress may play a role in the pathophysiology of infertility in these patients.

Adult↗
PubMed2004

Relationship between ROS production, apoptosis and DNA denaturation in spermatozoa from patients examined for infertility.

BACKGROUND: The aim of this study was to examine the role of apoptosis and reactive oxygen species (ROS) in inducing DNA damage in ejaculated spermatozoa. METHODS: We examined ejaculated spermatozoa from 31 patients examined for infertility and 19 healthy donors for apoptosis, production of ROS and DNA damage using annexin V binding, chemiluminescence assay and sperm chromatin structure assay. RESULTS: The percentage of spermatozoa that underwent apoptosis in the whole ejaculate and mature fraction was higher in the patients than in the donors (P<0.001 and P=0.009, respectively). Levels of ROS in the whole ejaculate and immature fraction were higher in the patients than in the donors (P=0.002 and P=0.009). Apoptosis was significantly correlated with ROS within patients in the whole ejaculate [r (95% confidence interval)=0.53 (0.19-0.86)] and in the mature [0.71 (0.39-1.00)] and immature spermatozoa [0.75 (0.45-1.00)]. Only apoptosis and the DNA fragmentation index (DFI) were significantly correlated within patients in the whole ejaculate [0.57 (0.18-0.97)]. CONCLUSIONS: DNA damage may be induced by oxidative assault. Apoptosis may not contribute significantly to the DNA damage.

Antioxidants↗
PubMed2004

Initial evaluation of robotic technology for microsurgical vasovasostomy.

PURPOSE: Conventional microscope assisted vasovasostomy (MAVV) is a technically difficult procedure that is most successful in the hands of well-trained microsurgeons. Robotics may help surgeons overcome the microsurgical challenges of tremor, limited dexterity, miniaturized instrumentation and use of fine suture. We determine the feasibility of a robotic assisted vasovasostomy (RAVV) and compare performance measures with those of conventional MAVV. MATERIALS AND METHODS: One surgeon performed 10 vasovasostomies with a modified 1-layer technique and 9-zero suture on fresh human vas specimens using the robot in 5 RAVV cases and standard microsurgical instrumentation in 5 MAVV cases. Pre-specified performance measures and adverse haptic events (broken sutures, bent needles or loose stitches) were recorded. Patency was evaluated by instilling saline through the anastomoses. RESULTS: Mean operating time and number of adverse haptic events were higher for RAVV than for MAVV (84 vs 38 minutes, p = 0.01; 2.4 vs 0.0 events, p = 0.03). The number of needle passes required for the 6 full-thickness stitches was similar in both groups (16.8 vs 15.2 passes, p = 0.55). Although no tremor occurred during RAVV, minimal to moderate amounts occurred during MAVV. Minimal fatigue was noted for both groups. Patency was confirmed in all 10 operations. CONCLUSIONS: Use of RAVV in this human ex vivo vas model was feasible. While RAVV took longer to perform and was associated with adverse haptic events, elimination of tremor and comparable patency rates suggest that it may be a viable surgical alternative for microsurgical vasovasostomy.

Equipment Design↗
PubMed2004

Infertility.

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Anastomosis, Surgical↗
PubMed2003

Negative effects of increased sperm DNA damage in relation to seminal oxidative stress in men with idiopathic and male factor infertility.

OBJECTIVE: To examine the effects of increased sperm DNA damage in relation to seminal oxidative stress in men with idiopathic and male factor infertility. Prospective study. SETTINGS: Infertility clinic at a tertiary care academic institution. PATIENT(S): Ninety-two infertile men with normal female partners. Sixteen fertile donors served as the control group. INTERVENTION(S): Standard semen analysis and assessment of levels of seminal oxidative stress. Assisted reproductive techniques in 33 of the 92 patients (IUI [n = 19], IVF [n = 10], and intracytoplasmic sperm injection [n = 4]). MAIN OUTCOME MEASURE(S): Sperm DNA damage by sperm chromatin structure assay. Results were expressed as DNA fragmentation index. RESULT(S): Patients were classified as having either idiopathic (n = 23) or male factor infertility (n = 69). Patients with idiopathic and male factor infertility had significantly higher DNA fragmentation index and oxidative stress compared with the case of fertile donors. A clinical pregnancy was achieved in 9 (27%) of 33 patients with assisted reproductive techniques. Significantly higher DNA fragmentation index and oxidative stress were found in men who failed to initiate a pregnancy after assisted reproductive techniques (n = 24), compared with the cases of those who succeeded and of the fertile donors. DNA fragmentation index was correlated positively with oxidative stress (r = 0.27), and negatively with fertilization (r = -0.70) and embryo quality (r = -0.70). CONCLUSION(S): Sperm DNA damage is significantly increased in men with idiopathic and male factor infertility and in men who failed to initiate a pregnancy after assisted reproductive techniques. Such an increase may be related to high levels of seminal oxidative stress.

Adult↗
PubMed2003

Oxidative stress is associated with increased apoptosis leading to spermatozoa DNA damage in patients with male factor infertility.

OBJECTIVE: To evaluate ejaculated spermatozoa from patients with male factor infertility for the role of cytochrome c and caspases 9 and 3 (the proteins known to mediate apoptosis) and to examine association between semen quality and apoptosis in the presence of oxidative stress. DESIGN: Prospective study. SETTING: Male infertility clinic at a tertiary health care center. PATIENT(S): Semen specimens from 35 patients with idiopathic infertility and 8 normal healthy donors. MAIN OUTCOME MEASURE(S): Levels of ROS, cytochrome c, and caspases 9 and 3 and semen variables. RESULT(S): Compared with normal donors, infertile patients had significantly higher levels (expressed as median [25th and 75th percentiles]) of ROS (4.15 x 10(6) counted photons per minute [cpm] [0.26, 40.16 x 10(6) cpm] vs. 0.06 x 10(6) cpm [0.02, 0.29 x 10(6) cpm]; P<.01), cytochrome c (2.78 [2.21, 43.65 vs. 1.5 [1.25, 2.2]; P<.01)], caspase 9 (2.52 [0.9, 4.28] vs. 6 [4.85, 7.63]; P<.006), and caspase 3 (0.56 [0.32, 1.02] vs. 1.69 [1.66, 2.67]; P<.01). Semen variables (motility, concentration, and morphology) were negatively correlated with caspase 9 and 3 (P<.05). Reactive oxygen species was positively correlated with cytochrome c (r=.43; P<.03), caspase 9 (r=.56; P<.001), and caspase 3 (r=.65;P<.01). CONCLUSION(S): Infertile men have decreased sperm variables induced by higher ROS levels in semen. A positive relationship exists between increased sperm damage by ROS and higher levels of cytochrome c and caspases 9 and 3, which indicate positive apoptosis in patients with male factor infertility.

Apoptosis↗
PubMed2003

Alterations in mitochondria membrane potential and oxidative stress in infertile men: a prospective observational study.

OBJECTIVE: To evaluate the mitochondrial membrane potential (MMP) of spermatozoa and its correlation with semen parameters and production of reactive oxygen species (ROS) in infertile men and healthy donors. DESIGN: Controlled prospective study. SETTING: Male infertility clinic, Glickman Urological Institute, The Cleveland Clinic Foundation, Cleveland, Ohio. PATIENT(S): Nineteen infertile men and 7 healthy volunteers. INTERVENTION(S): Standard semen analysis, assessment of MMP and ROS production in spermatozoa. The MMP was assessed by flow cytometry using the probe carbocyanine DiOC(6)(3) and ROS was measured with chemiluminescence assay using luminol. MAIN OUTCOME MEASURE(S): The results of MMP are reported as the median interquartile range (IQR) number of cells counted in different areas of fluorescence. Results of ROS measurement are expressed as x10(6) counted photons per minute per 20 million sperm (cpm). RESULT(S): The patients with abnormal semen parameters had a significantly lower MMP [1337.7 (1066.38, 1879.2)], and higher ROS [1.12 (0.26, 3.86)] than the donors [MMP: 2482.9 (2162.5, 3520.6)] and [ROS: 0.10 (0.01, 0.14)]. The MMP was positively correlated with sperm concentration (r = 0.62) and negatively correlated with the ROS produced (r = -0.45). CONCLUSION(S): Measuring MMP in spermatozoa provides useful information about a man's fertility potential. Increased ROS production by spermatozoa is associated with a decreased MMP.

Carbocyanines↗
PubMed2003

Evaluation of nuclear DNA damage in spermatozoa from infertile men with varicocele.

OBJECTIVE: To examine levels of sperm DNA damage and oxidative stress (OS) in infertile men with varicocele. DESIGN: Prospective controlled study. SETTING: Male infertility clinic, Glickman Urological Institute, Cleveland Clinic Foundation, Cleveland, Ohio. PATIENT(S): Thirty-one infertility patients and 16 fertile controls. INTERVENTION(S): Sperm DNA fragmentation index (DFI), levels of seminal reactive oxygen species (ROS), and total antioxidant capacity (TAC) were assessed using the sperm chromatin structure assay, chemiluminescence assay, and enhanced chemiluminescence assay, respectively. ROS-TAC score was calculated as a measure of OS. MAIN OUTCOME MEASURE(S): Median (interquartile range) DFI and ROS-TAC scores. RESULT(S): Sixteen of the 31 patients had left varicocele [grade I (n = 3), grade II (n = 10), and grade III(n = 3)], and the remaining 15 had normal genital examination. Patients with varicoceles had significantly higher percent DFI than controls (25%, range: 20%-35%; vs. 15%, range: 10%-22%). Patients with varicoceles had significantly lower ROS-TAC scores (21, range: 9.5-31) than the infertile patients with normal genital examination (34, range: 28-42) or the controls (40.3, range: 38-44). CONCLUSION(S): Infertile men with varicoceles showed significantly increased spermatozoal DNA damage that appears to be related to high levels of OS in semen.

Cell Nucleus↗
PubMed2002

Increased DNA damage in sperm from leukocytospermic semen samples as determined by the sperm chromatin structure assay.

OBJECTIVE: To determine DNA damage as measured by the sperm chromatin structure assay (SCSA) in subsets of human spermatozoa at different stages of maturation in patients who are undergoing infertility evaluation. DESIGN: Prospective study. SETTING: Andrology laboratory at a tertiary care hospital. PATIENT(S): Fifty-six patients undergoing infertility evaluation. Patients with normal semen parameters (n = 17), abnormal semen parameters (n = 29), leukocytospermia (n = 10), and a group of healthy fertile men (n = 18) were included in the study. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The shift of green (native DNA) to red (denatured, single-stranded DNA) fluorescence was measured and quantified using the expression alpha(t) (red fluorescence/[red + green fluorescence] per cell). Sperm DNA damage was examined in subsets of spermatozoa isolated by a three-step density gradient. The DNA damage was correlated with classic semen characteristics. RESULT(S): Leukocyte concentration in semen was directly correlated with chromatin alterations in immature and mature sperm. Leukocyte concentration in semen was also directly correlated with immature germ cell concentration and the percentage of abnormal forms in semen. CONCLUSION(S): The increase in chromatin alterations and DNA damage in sperm, as defined by the sperm chromatin structure assay from leukocytospermic samples may be related to alterations in the regulation of spermatogenesis.

Centrifugation, Density Gradient↗
PubMed2002

Increased sperm nuclear DNA damage in normozoospermic infertile men: a prospective study.

OBJECTIVE: To evaluate levels of sperm nuclear DNA damage in infertile men with normal and abnormal standard semen parameters. DESIGN: Prospective study. SETTING: Male infertility clinic. PATIENT(S): Ninety-two men seeking infertility treatment and 16 fertile volunteers. INTERVENTION(S): Standard semen analysis was performed according to the World Health Organization guidelines. MAIN OUTCOME MEASURE(S): Sperm DNA damage was assessed by sperm chromatin structure assay and the results expressed as %DFI. RESULT(S): Of the 92 patients, 21 (23%) had normal standard sperm parameters (concentration, motility, and normal sperm forms), while 71 (77%) had an abnormality in one or more of these parameters. The %DFI [median (25th and 75th percentiles)] in infertile men with normal sperm parameters [23 (15, 32)] was significantly higher than fertile donors [15 (11, 20)] (P=.02), but not significantly different from infertile men with abnormal sperm parameters [28 (18, 41)] (P=.27). CONCLUSION(S): The results of this study indicate that a significant increase in SCSA-defined DNA damage can be found in sperm from infertile men with normal standard sperm parameters. Therefore, sperm DNA damage analysis may reveal a hidden abnormality of sperm DNA in infertile men classified as idiopathic based on apparently normal standard sperm parameters.

Cell Nucleus↗
PubMed2002

Effect of cigarette smoking on levels of seminal oxidative stress in infertile men: a prospective study.

OBJECTIVE: To investigate levels of seminal oxidative stress (OS) and sperm quality in a group of infertile men with a history of cigarette smoking. DESIGN: A prospective clinical study. SETTING: Male infertility clinic, Urological Institute, the Cleveland Clinic Foundation, Cleveland, Ohio. PATIENT(S): Infertile men who smoked cigarettes (n = 20), infertile men who were nonsmokers (n = 32), and healthy nonsmoking donors (n = 13). INTERVENTION(S): Genital examination, standard semen analysis, sperm DNA damage. MAIN OUTCOME MEASURE(S): Levels of seminal reactive oxygen species (ROS) and total antioxidant capacity (TAC) measured by a chemiluminescence assay and seminal OS assessed by calculating a ROS-TAC score. Sperm DNA damage was measured by sperm chromatin structure assay. RESULT(S): Smoking was associated with a 48% increase in seminal leukocyte concentrations (P<.0001), a 107% increase in ROS levels (P=.001), and a 10-point decrease in ROS-TAC scores (P=.003). Differences in standard sperm variables and DNA damage indices between the infertile smokers and infertile nonsmokers were not statistically significant. CONCLUSION(S): Infertile men who smoke cigarettes have higher levels of seminal OS than infertile nonsmokers. Given the potential adverse effects of seminal OS on fertility, physicians should advise infertile men who smoke cigarettes to quit.

Analysis of Variance↗