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Anthony J Thomas

Publications and source records attributed to Anthony J Thomas.

At least 37 records · Page 2Linked to original sources
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↗
PubMed2002

Leukocytospermia is associated with increased reactive oxygen species production by human spermatozoa.

To investigate the role of increased seminal leukocytes in enhancing reactive oxygen species (ROS) production by human spermatozoa.A prospective study. Male infertility clinic.Forty-eight infertile men. Standard semen analysis. Assessment of sperm nuclear DNA damage by sperm chromatin structure assay. Incubation of spermatozoa from nonleukocytospermic samples with blood neutrophils. Spontaneous and phorbol 12-myristate 13-acetate (PMA)-induced ROS production in pure-sperm suspensions (after removal of leukocytes) as measured by a chemiluminescence assay. Levels of spontaneous and PMA-induced ROS production in pure-sperm suspensions from the infertile men with a diagnosis of leukocytospermia (n = 16) were significantly higher compared with the case of infertile men without leukocytospermia (n = 32) and with the case of a control group of healthy volunteers (n = 13). A similar pattern of increased ROS was observed when spermatozoa were incubated with blood neutrophils. Leukocytospermia was associated with a significant decrease in sperm motility and increase in DNA damage. Increased seminal leukocytes may play a role in stimulating ROS production by human spermatozoa. Such stimulation may be mediated via direct cell-cell contact or by soluble products released by leukocytes. Poor sperm quality in leukocytospermic samples may be due to leukocyte-mediated oxidative stress.

DNA Damage↗
PubMed2002

Optimizing laboratory use of human vas deferens specimens for microsurgical practice.

OBJECTIVES: To determine whether freezing harvested human vas deferens would preserve the tissue for later microsurgical practice. Learning and maintaining microsurgical skills requires laboratory practice. The proper preservation of the human vas deferens is important if harvested specimens are to be used for laboratory vasovasostomy. METHODS: Segments of human vas deferens harvested at the time of radical retropubic prostatectomy were preserved at -20 degrees C without media, in normal saline and in glycerol. At 2 weeks, the specimens were thawed and graded for freshness of appearance, mucosal preservation, mucosal suturing quality, muscularis preservation, and muscularis suturing quality at laboratory vasovasostomy (grade 1, poor; 2, fair; and 3, good). Mucosa and muscularis scores were calculated as the sum of the respective preservation and suturing quality grades. The preserved samples were compared with fresh human vas deferens specimens. RESULTS: Freezing human vas deferens segments in normal saline or glycerol improved the mucosa and muscularis scores at 2 weeks compared with freezing tissues without media. However, a decrease in the freshness of appearance grade was noted. None of the freezing methods resulted in tissue quality as good as fresh vas deferens. CONCLUSIONS: Human vas deferens can be preserved for later microsurgical vasovasostomy practice at -20 degrees C. Freezing in normal saline and glycerol improved the mucosa and muscularis scores compared with freezing without media, although a decrease in the freshness of appearance grade was noted. All three methods of freezing provided sufficient preservation for laboratory microsurgical vasovasostomy compared with fresh tissue.

Cryopreservation↗
PubMed2002

Laparoscopic management of congenital seminal vesicle cysts associated with ipsilateral renal agenesis.

PURPOSE: Congenital cysts of the seminal vesicles associated with ipsilateral renal abnormalities are rare. When they are symptomatic, open surgical excision has been the treatment of choice. We present our experience with laparoscopic management and provide a detailed literature review of this entity. MATERIALS AND METHODS: Since 1985, 3 patients with symptomatic seminal vesicle cysts and ipsilateral renal agenesis have been treated at our center. Open surgical excision was performed in 1 patient and laparoscopic management was performed in the other 2. RESULTS: Mean patient age was 35.7 years (range 30 to 42). Presenting symptoms were perineal pain in all 3 cases, dysuria in 2, irritable voiding in 2 and testicular pain in 1. Mean laparoscopic operative time was 195 minutes and mean estimated blood loss was 325 cc. Transabdominal or transrectal ultrasound was performed in 2 cases and computerized tomography was performed in all 3. CONCLUSIONS: Seminal vesicle cysts associated with ipsilateral renal agenesis are rare but they should be considered in men with otherwise inexplicable irritable voiding symptoms, perineal discomfort or other genitourinary complaint of unclear etiology. Evaluation should include digital rectal examination, transrectal and transabdominal ultrasound, computerized tomography and cystoscopy. Laparoscopy provides excellent intraoperative access and visualization with minimal postoperative morbidity. It is likely to become the treatment of choice for this rare developmental anomaly.

Adult↗
PubMedDate not supplied

The use of novel semen quality scores to predict pregnancy in couples with male-factor infertility undergoing intrauterine insemination.

The purpose of this study was to determine whether 2 new semen quality (SQ) scores could predict pregnancy in patients undergoing intrauterine insemination (IUI) for male-factor infertility and whether an overall score could help in counseling these couples with assisted reproductive technique (ART) options. Ninety-three couples with male-factor infertility were examined for semen analysis. Samples were prepared by density gradient separation (47% and 90%), and IUI was performed. On the basis of the 2 semen scores (SQ and relative quality [RQ]), the IUI-semen pregnancy score (IUI-SPS) was calculated. Of the 192 IUI cycles, 14% (27 of 192) resulted in pregnancy. Both prewash SQ and RQ scores were significantly related to pregnancy (P =.02 and P <.001), as was the postwash RQ score (P <.001). Of the IUI cycles in which the postwash RQ score was greater than 125, 40% (13 of 32) resulted in pregnancy compared to 9% of cycles (14 of 160) in which the postwash SQ score was less than 125. The prewash IUI-SPS score was significantly related to IUI-induced pregnancy (P <.001). Both the pre- and postwash SQ and RQ scores can predict pregnancy in male infertility patients undergoing IUI. Patients with an IUI-SPS less than 150 may be advised to seek in vitro fertilization (IVF), whereas those with an IUI-SPS greater than 150 may be advised to seek IUI.

Female↗
PubMedDate not supplied

Enhanced chemiluminescence assay vs colorimetric assay for measurement of the total antioxidant capacity of human seminal plasma.

Although the enhanced chemiluminescence assay is commonly used to measure the nonenzymatic total antioxidant capacity (TAC) of the human seminal plasma, it is cumbersome, expensive, and time-consuming. We describe herein an alternate method to measure TAC that is based on the ability of antioxidants in seminal plasma to interfere with a reaction between 2,2'-azino-di-[3-ethylbenzthiazoline sulphonate] and metmyoglobin with H(2)O(2). This reaction produces a relatively stable blue-green color with absorbance maxima at 600 nm. We compared this colorimetric assay with our established chemiluminescence method and assessed quality control parameters (ie, intra-assay and interassay variabilities) in addition to intraobserver and interobserver differences. Our results show that the colorimetric assay was fairly predictive of antioxidant capacity similar to the chemiluminescence assay (P <.001). Furthermore, there was a high level of agreement between the duplicate measures by the same observer (intraobserver) and intra-assay variability, with a concordance correlation coefficient of 0.99. The interassay coefficient of variation was 4.7% (overall). The mean +/- SD of the difference between the 2 observers was 2.98% +/- 4.1%. In conclusion, we found that the colorimetric assay is a reliable and accurate method to evaluate seminal TAC, and it could be used as a simpler, rapid, and cheaper alternative to the chemiluminescence assay.

Antioxidants↗