Energy enhancement of the target surface electron by using a 200 TW sub-picosecond laser.

One order of magnitude energy enhancement of the target surface electron beams with central energy at 11.5 MeV is achieved by using a 200 TW, 500 fs laser at an incident angle of 72° with a prepulse intensity ratio of 5×10-6. The experimental results demonstrate the scalability of the acceleration process to high electron energy with a longer (sub-picosecond) laser pulse duration and a higher laser energy (120 J). The total charge of the beam is 400±20 pC(E>2.7 MeV). Such a high orientation and mono-energetic electron jet would be a good method to solve the problem of the large beam divergence in fast ignition schemes and to increase the laser energy deposition on the target core.

Cardiotonic steroids induce anti-angiogenic and anti-proliferative profiles in first trimester extravillous cytotrophoblast cells.

OBJECTIVE: Preeclampsia (preE), is characterized by abnormal placental invasion and function. Marinobufagenin (MBG), a cardiotonic steroid (CTS), inhibits cytotrophoblast (CTB) cell functions that are critical for normal placental development. This study tests the hypothesis that CTSs induce anti-angiogenic and anti-proliferative effects in CTB cells. METHODS: Human extravillous CTB cells of the line Sw-71, derived from first trimester chorionic villus tissue, were incubated with 0, 0.1, 1, 10, and 100 nM of each of three CTSs (MBG, cinobufatalin (CINO) and ouabain (OUB)) for 48 h. Thereafter, levels of pro-angiogenic (vascular endothelial growth factor (VEGF165), placental growth factor (PlGF)) and anti-angiogenic (soluble fms-like tyrosine kinase-1 (sFlt-1), soluble endoglin (sEng)) factors were measured in culture media using ELISA kits. Expression of three receptors (VEGF receptor 1 (VEGFR1), angiogenic angiotensin type 1 receptor (AT1) and anti-angiogenic angiotensin type 2 receptor (AT2)) were assayed using immunoblotting (western blots) in cell lysates. RESULTS: sFlt-1 and sEng secretion were increased while VEGF165 and PIGF were decreased in the culture media of CTB cells treated with 1 nM or more of each CTSs (p < 0.01 for each). The AT2 receptor expression was up-regulated (p < 0.05) in CTB cells treated with 1 nM or more of MBG and CINO and with 100 nM OUB, while AT1 and VEGFR1 expressions decreased (p < 0.05) with 1 nM or more of MBG and 10 nM or more of CINO and OUB. CONCLUSIONS: CTSs influence extravillous CTB cells to induce an anti-angiogenic and anti-proliferative profile.

High-harmonic generation and parametric amplification in the soft X-rays from extended electron trajectories.

We report, for the first time, the generation of high-order harmonics in a spectral range between 200 eV and 1 keV with an unusual spectral property: only every 4(th) (4i + 1, i∈ℵ) harmonic line appears, whereas the usual high-harmonic spectra consist of every odd (2i + 1) harmonic. We attribute this unique property to the quantum path interference of two extended electron trajectories that experience multiple re-scattering. In the well-established theory, electrons emitted via tunnel ionisation are accelerated by a laser field, return to the ion and recombine. The acceleration typically lasts for less than one optical cycle, and the electrons radiate in the extreme ultraviolet range at recombination. In contrast, for extended trajectories, electrons are accelerated over two or more optical cycles. Here, we demonstrate that two sets of trajectories dominate and provide substantial contributions to the generated soft X-ray radiation because they fulfil the resonance condition for X-ray parametric amplification.

Parametric amplification of attosecond pulse trains at 11†nm.

We report the first experimental demonstration of the parametric amplification of attosecond pulse trains at around 11 nm. The helium amplifier is driven by intense laser pulses and seeded by high-order harmonics pulses generated in a neon gas jet. Our measurements suggest that amplification takes place only if the seed pulse-trains are perfectly synchronized in time with the driving laser field in the amplifier. Varying the delay, we estimate the durations of the individual extreme ultraviolet pulses within the train to be on the order of 0.2 fs. Our results demonstrate that strong-field parametric amplification can be a suitable tool to amplify weak attosecond pulses from non-destructive pump-probe experiments and it is an important step towards designing amplifiers for realization of energetic XUV pulses with sub-femtosecond duration using compact lasers fitting in university laboratories.

Gain lifetime measurement of a Ni-like Ag soft X-ray laser.

Experimental results of a two-stage Ni-like Ag soft X-ray laser operated in a seed-amplifier configuration are presented. Both targets were pumped applying the double-pulse grazing incidence technique with intrinsic travelling wave excitation. The injection of the seed X-ray laser into the amplifier target was realized by a spherical mirror. The results show amplification of the seed X-ray laser and allow for a direct measurement of the gain lifetime. The experimental configuration is suitable for providing valuable input for computational simulations.

Low energy prepulse for 10 Hz operation of a soft-x-ray laser.

The influence on Nickel-like Molybdenum soft-x-ray laser performance and stability of a low energy laser prepulse arriving prior to the main laser pumping pulses is experimentally investigated. A promising regime for 10 Hz operation has been observed. A four times increase in soft-x-ray laser operation time with a same target surface is demonstrated. This soft-x-ray laser operation mode corresponds to an optimum delay between the prepulse and the main pulses and to a prepulse energy greater than 20 mJ. We also show that this regime is not associated with a weaker degradation of the target or any reduced ablation rate. Therefore the role of preplasma density gradient in this effect is discussed.

Note: A large aperture four-mirror reflective wave-plate for high-intensity short-pulse laser experiments.

We report on a four-mirror reflective wave-plate system based on a phase-shifting mirror (PSM) for a continuous variation of elliptical polarization without changing the beam position and direction. The system presented and characterized here can replace a conventional retardation plate providing all advantages of a PSM, such as high damage-threshold, large scalability, and low dispersion. This makes reflective wave-plates an ideal tool for ultra-high power laser applications.

Ultrasound-guided follicular aspiration in squirrel monkeys.

The objective of this study was to test whether ultrasound-guided oocyte retrieval is an effective mechanism for collecting oocytes in squirrel monkeys. Although ultrasound-guided follicular aspiration has been described in Old World primates, oocyte retrieval in New World primates is typically performed via laparoscopy or laparotomy. However, these procedures, especially the first, can be invasive. Ultrasound has been used for pregnancy monitoring in multiple species of primates including Saimiri spp. Transabdominal ultrasound as a diagnostic tool is non-invasive. Transabdominal ultrasound was utilized to visualize ovarian follicles during aspiration under light anesthesia. This procedure resulted in collection of a total of 29 oocytes from six animals with minimal post-procedural pain. Manipulated animals were returned to the social group the same day.

Analysis of surgical complications and patient outcomes in a residency training program.

OBJECTIVES: This study compares surgical complications and patient outcomes between pelvic reconstructive surgery performed by an experienced surgeon (group 1) and those performed by resident physicians with the senior surgeon assisting and teaching (group 2). STUDY DESIGN: During a 5-year interval, 310 consecutive women underwent vaginal prolapse repair. Demographic, historic, and preoperative physical examination variables were compared. Intraoperative and postoperative outcomes were also compared. RESULTS: Patients operated on by the senior surgeon (Bob L. Shull) were thinner (group 1 vs group 2: 25.8 kg/m2 vs 27.1 kg/m2; P =.014), more often had prior prolapse or incontinence procedures (55% vs 33%; P <.001), and required shorter operating times (124 minutes vs 140 minutes; P =.002). The senior surgeon's patients differed from the resident physicians' patients with regard to stage of pelvic organ prolapse. No differences were observed for patient age (P =.51), estimated blood loss (P =.50), urologic complications (P =.59), and hospital stay (P =.25). The durability of the repairs was not different between the groups. CONCLUSIONS: We have demonstrated that in a tertiary referral practice resident surgeons can be taught to perform complex vaginal surgery with the only observed disadvantage being a slightly prolonged operative time.

A transvaginal approach to repair of apical and other associated sites of pelvic organ prolapse with uterosacral ligaments.

OBJECTIVE: The objectives of this study were (1) to describe a group of women with pelvic organ prolapse associated with apical loss of support through grading with the Baden-Walker halfway system before, during, and after the corrective operation, (2) to describe the operative repair of the support defects, (3) to report the morbidity associated with the operative repair, and (4) to assess the durability of the repair at each site. STUDY DESIGN: Between January 1, 1994, and December 31, 1998, a total of 302 consecutive women with apical and associated other support defects were evaluated before, during, and after the corrective operation by the senior author (Bob L. Shull). All patients underwent transvaginal reconstructive surgery with native tissue. Two hundred eighty-nine patients (96%) returned for at least one postoperative visit, and they constitute the group used for the follow-up data. Perioperative morbidity was considered to include hemorrhage necessitating homologous blood transfusion, visceral injury, neurologic impairment, or death. Durability was assessed by means of life-table analysis for each of 5 sites in the vagina. RESULTS: All patients had preoperative or intraoperative evidence of grade 1 or greater apical loss of support of and at least one other site of pelvic organ prolapse. Two hundred eighty-nine patients (96%) returned for at least one postoperative visit. Two hundred fifty-one patients (group 1, 87%) had optimal anatomic outcomes, with no persistent or recurrent support defects at any site. Thirty-eight patients (group 2, 13%) had one or more sites with at least grade 1 loss of support during the follow-up interval. Twenty-four of these 38 patients had grade 1 defects that were detectable only on careful pelvic examination. Fourteen of these patients (5%) had grade 2 or greater persistent or recurrent support defects. The anterior segment (bladder) was the site with the most persistent or recurrent support defects, which means that it was the site of the least durable repair. The urethra and cuff had the most durable repairs. Morbidity included a 1% transfusion rate, a 1% ureteral injury or ureteral kinking rate, and a 0.3% postoperative death rate. CONCLUSION: Careful preoperative and intraoperative evaluation of pelvic support defects and the use of native connective tissue and uterosacral ligaments are associated with excellent anatomic outcomes. The durability of the surgical correction varies according to the individual site of repair and the duration of postoperative follow-up.

Gestational diabetes screening in subsequent pregnancies of previously healthy patients.

OBJECTIVE: Our purpose was to evaluate women without gestational diabetes mellitus in an index pregnancy for the likelihood that gestational diabetes would develop and for risk factors for carbohydrate intolerance in a subsequent pregnancy. STUDY DESIGN: A retrospective review of medical records at a teaching hospital universally screening for gestational diabetes identified multiparous women who had been delivered twice between 1994 and 1997 and who, in the first (index) pregnancy, had had a normal result on a screening test with 50 g of glucose used in a "glucola" beverage (< or =140 mg/dL). RESULTS: In this population with normal glucose screening values in the index pregnancy, 352 (92.4%) of 381 women had at least one risk factor for gestational diabetes. However, none of the 381 women had gestational diabetes in the subsequent pregnancy (0/381, 95% confidence interval < or =1%), including 45 (12. 4%) who had an abnormal result on the 50-g glucose screening test. Regression analysis showed this test result in the index pregnancy (P =.001) to be the only studied variable significantly associated with the 50-g glucose value in the subsequent pregnancy. CONCLUSION: Despite a high rate of risk factors for gestational diabetes, women in our population with a normal glucose value in an index pregnancy have a minimal risk (<1%) that gestational diabetes will develop in a subsequent singleton pregnancy within 4 years. This factor may be included in determining whether women should undergo screening for gestational diabetes.

The papanicolaou smear: inadequate screening test for bacterial vaginosis during pregnancy.

OBJECTIVE: Our purpose was to evaluate the ability of the Papanicolaou smear to identify bacterial vaginosis in comparison with the Amsel clinical criteria. STUDY DESIGN: We retrospectively identified 159 pregnant women screened for bacterial vaginosis with the Amsel criteria who had a contemporaneous Papanicolaou smear and negative results on screening for Chlamydia trachomatis and Neisseria gonorrhoeae. Bacterial vaginosis was identified in 45 women. We used the McNemar chi(2) test to determine discrepancies between the two screening methods for the detection of bacterial vaginosis. RESULTS: Compared with the Amsel criteria, the sensitivity and specificity of the Papanicolaou smear for yielding a diagnosis of bacterial vaginosis were 49% (95% confidence interval, 36%-64%) and 93% (95% confidence interval, 86%-97%), respectively, with a positive predictive value of 73% and a negative predictive value of 82%. The detection of bacterial vaginosis by Papanicolaou smear was significantly different from that by Amsel criteria (P =. 01). CONCLUSION: The Papanicolaou smear is not a reliable screening test for bacterial vaginosis during pregnancy.

Hormone withdrawal symptoms in oral contraceptive users.

OBJECTIVE: To measure the timing, frequency, and severity of hormone-related symptoms in oral contraceptive (OC) users, specifically to compare active-pill with hormone-free intervals. METHODS: Using daily diaries, women recorded pelvic pain, bleeding, headaches, analgesic use, nausea or vomiting, bloating or swelling, and breast tenderness during active-pill intervals and hormone-free intervals. Participants either had no prior OC use, had taken OCs and were restarting, or had been taking OCs continuously for 12 months or longer. RESULTS: Two hundred sixty-two women, 26 with no previous OC use, 43 prior users, and 193 current users, provided daily records of hormone-related symptoms. Subjects with no prior OC use and prior users restarting were similar in no recent OC use, and because of the small sample, they were pooled for analysis as new-start OC users. Current users had patterns of symptoms that were more frequent during hormone-free intervals than during the three active-pill weeks. These included pelvic pain (70% versus 21%, P < .001), headaches (70% versus 53%, P < .001), use of pain medication (69% versus 43%, P < .001), bloating or swelling (58% versus 19%, P < .001), and breast tenderness (38% versus 16%, P < .001). Similar patterns were seen in new-start OC users after the first cycle. Among new-start OC users, menstrual flow patterns, headache, bloating or swelling, and breast-tenderness symptoms decreased during the three cycles to approach those levels of current users. CONCLUSION: Almost all symptoms assessed were significantly worse during the 7-day hormone-free interval than during the 21 days of hormone-containing pills.

Jelly beans as an alternative to a fifty-gram glucose beverage for gestational diabetes screening.

OBJECTIVE: This study tested the hypothesis that a standardized dose of jelly beans could be used as an alternative sugar source to the 50-g glucose beverage to screen for gestational diabetes mellitus. STUDY DESIGN: One hundred sixty pregnant women at 24 to 28 weeks' gestation were recruited for a prospective study to compare 2 sugar sources for serum glucose response, side effects, preference, and ability to detect gestational diabetes mellitus. Patients were randomly assigned to consume 50-g glucose beverage or 28 jelly beans (50 g simple carbohydrate). Serum glucose values were determined 1 hour later. The test was later repeated with the other sugar source. Finally, a 100-g 3-hour oral glucose tolerance test was performed. Participants completed a questionnaire recording subjective outcome variables. American Diabetes Association criteria were used to interpret all test results. RESULTS: Among 136 participants completing the study no significant differences were found between 1-hour serum glucose values (116.5 +/- 27 mg/dL with 50-g glucose beverage, 116.9 +/- 23.6 mg/dL with jelly beans; P =.84), frequency of discrepant results (P =.47), sensitivity, specificity, or predictive value. Jelly beans yielded fewer side effects (38% with 50-g glucose beverage, 20% with jelly beans; P <.001) and were preferred by 76% of participants (P <.001). Five cases (3.7% incidence) of gestational diabetes mellitus were diagnosed, 3 with 50-g glucose beverage alone, 1 with jelly beans alone, and 1 with both sugar sources. CONCLUSIONS: Jelly beans may be used as an alternative to the 50-g glucose beverage as a sugar source for gestational diabetes mellitus screening. The 2 sources provoke similar serum glucose responses. Patients report fewer side effects after a jelly bean challenge than after a 50-g glucose beverage challenge.

Incorporation of a GnRH agonist, leuprolide acetate, into regimens with exogenous gonadotropins to produce ovarian stimulation and ovulation in the nonpregnant squirrel monkey.

This study was designed to measure the effects of variations in the length of pretreatment with a GnRH agonist, leuprolide acetate (LA), on subsequent follicular development and ovulation. The hypothesis was that the duration of LA suppression of pituitary function does not adversely affect ovarian response to standardized ovulation induction protocols in squirrel monkeys. The first phase determined the dose and duration of LA needed to achieve a hypogonadal state. One of two groups received daily subcutaneous injections of 50 microg of LA. The other received a single injection of 175 microg of a depot suspension of LA. Sera were assayed for estradiol (E2) and progesterone (P). E2 and P levels increased 2- to 5-fold with peak levels on days 4 and 7, respectively. Suppression of steroid levels took 10 to 15 days in the LA-treated group. Depot-LA did not effectively suppress steroid production. After suppression, females receiving daily LA received five daily injections of hMG to stimulate follicular development. E2 and P increased in these animals. These results suggest that cycling squirrel monkeys have P-secreting capacity throughout the cycle. This may explain how the squirrel monkey is able to accommodate both a short (4-5 day) luteal phase of their 9 day cycle and implantation from 5 to 7 days after ovulation. A second study compared exogenous follicle stimulating hormone (FSH) to endogenous gonadotropins released as a response to LA in ovulation induction. Steroid production and hCG-induced ovulation were assessed. LA treatment was compared to a standard ovulation induction protocol by using a randomized cross-over measures design. There were no differences in E2 and P levels in response to dosages of either LA or hMG. The ovulatory response following LA treatment was not significantly greater than that using FSH. The number of animals with unovulated, large follicles was greater on the FSH protocol (12/18) compared to the LA protocol (3/18). Thus, a single injection of a depot preparation of LA is sufficient to stimulate follicular development and ovulation when followed by an hCG injection. Based on this observation and the data on unovulated large follicles, it is suggested that the ovary responds more readily to endogenous gonadotropins released by LA than to exogenous FSH.

Luteal phase sertraline treatment for premenstrual dysphoric disorder. Results of a double-blind, placebo-controlled, crossover study.

OBJECTIVE: To test the efficacy of late-luteal phase dosing of sertraline hydrochloride in women with moderate-to-severe premenstrual dysphoric disorder. This highly prevalent disorder often causes significant psychosocial impairment. DESIGN: Double-blind, crossover trial of each 2-menstrual cycle of baseline, sertraline treatment, and placebo. Randomization to sertraline treatment vs placebo occurred after a 2-cycle, drug-free period. SETTING: A large outpatient multispecialty clinic in central Texas. PATIENTS: Fifty-seven women aged 19 to 49 years with a Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, diagnosis of premenstrual dysphoric disorder. INTERVENTIONS: Late-luteal phase treatment with sertraline hydrochloride in daily doses of 50 mg (cycle 1) followed by 100 mg (cycle 2) vs placebo. MAIN OUTCOME MEASURES: The 22-item calendar of premenstrual experiences was completed daily and constituted the primary outcome measure, consisting of a total score and behavioral and physical factor scores. RESULTS: A repeated-measures analysis of variance for crossover designs found a significant beneficial effect from sertraline treatment in improving the calendar of premenstrual experiences total (P < .01), behavioral factor (P < .01), and physical factor (P < .04) scores. Most women improved when taking sertraline, 50 mg, although a dose increase to 100 mg yielded further improvement in approximately 25% of women. Use of sertraline was extremely well tolerated; the only adverse event reported by 10% or more of women was insomnia in 8 (14%) of them. CONCLUSIONS: Luteal phase treatment with sertraline was a safe and effective treatment for moderate-to-severe premenstrual dysphoric disorder. Further controlled studies are needed to confirm the results of this preliminary study.

Cystoscopic findings consistent with interstitial cystitis in normal women undergoing tubal ligation.

PURPOSE: We test the hypothesis that women without chronic pelvic pain or irritative voiding symptoms do not demonstrate petechial hemorrhages known as glomerulations that are characteristic of patients with interstitial cystitis. MATERIALS AND METHODS: A prospective cohort design was used for examination with cystoscopy and bladder distention of 20 asymptomatic women undergoing tubal ligation. Cystoscopy with the patient under general anesthesia was performed to inspect the bladder mucosa before and after distention at 70 cm. of water pressure for 2 or 6 minutes. Photographs of the right, posterior and left of the bladder surfaces taken before and after the distention were scored on a scale of 1 to 5 using a panel of standards. Five urologists blinded to the source of individual photographs independently evaluated 120 research images interspersed with 46 other pictures from a library containing images from 19 symptomatic patients with and without interstitial cystitis. RESULTS: A total of 20 normal women with a mean age plus or minus standard deviation of 29+/-6 years consented to participate in this trial during laparoscopic tubal ligation. Photographs of bladder sites before and after distention with 890+/-140 ml. were scored as 1.4+/-0.3 (before distention) and 3.1+/-1.1 (after distention) on the scale of 1 to 5. The increase in scores following distention in normal subjects was seen to the same degree and in the same proportion as in patients with symptoms of interstitial cystitis (8 of 19 symptomatic patients in this series met current diagnostic criteria for interstitial cystitis). Slight but significant differences were seen among sites in the bladder but not between 2 and 6-minute distention durations. CONCLUSIONS: Bladder mucosal lesions characteristically associated with irritative voiding symptoms and pelvic pain in patients diagnosed with interstitial cystitis were observed in asymptomatic women.

Cryopreservation of murine zygotes for use in testing culture environments.

Developing one-cell mouse zygotes are more sensitive to in vitro environmental conditions than are cleavage-stage embryos. However, for convenience and reproducibility, cryopreserved two-cell zygotes are routinely used for such assays. Concern over the possibility of inducing damage by exposing one-cell zygotes to cryoprotective agents and freeze-thaw procedures during syngamy led us to examine one-cell zygotes, with and without visible pronuclei, in an effort to minimize or avoid these effects and obtain the highest possible developmental rate. In vivo fertilized mouse zygotes were collected 21 to 43 h after administration of human chorionic gonadotropin (hCG). Suspensions of zygotes in 2M ethylene glycol were aspirated into 0.25-ml plastic insemination straws and slowly cooled at -0.5 degree C/min to -40 degrees C before being plunged into liquid nitrogen for storage. Zygotes were thawed, rinsed, and placed in culture. Zygotes were examined initially for damage from the freeze-thaw procedure. Daily in vitro development was recorded. In this group of zygotes, no damage was apparent immediately after thawing, and a high degree of development in vitro was observed. Thus, usefulness of a cryopreservation method for one-cell murine zygotes has been confirmed.

Laparoscopy during pregnancy: a study of five fetal outcome parameters with use of the Swedish Health Registry.

OBJECTIVE: Our purpose was to compare five fetal outcome variables between laparoscopy and laparotomy performed during pregnancy with use of the Swedish Health Registries from 1973 to 1993. STUDY DESIGN: A dataset was produced by linking computerized records from three Swedish Health Registries. The dataset includes records for women who were delivered between 1973 and 1993 and had an operation within 1 year before giving birth. The data were divided according to surgical procedure(s) and grouped according to diagnostic code(s). The following end points were studied in singleton births: birth weight, gestational duration, intrauterine growth restriction, congenital malformations, stillbirths, and neonatal deaths. In the analysis confounding by maternal age and parity, year of birth of the infant, maternal smoking, period of involuntary infertility, and maternal cohabitation was taken into consideration. A chi 2 analysis was used to compare proportions. Variables were stratified with use of the Mantel-Haenszel procedure. Risk ratios were calculated for observed/expected ratios when outcomes for the total population were compared or as odds ratios when laparoscopy and laparotomy cohorts were compared. Expected values were calculated from the total population of women with singleton pregnancies. RESULTS: The study covered 2,015,000 deliveries in Sweden from 1973 to 1993. Data for this study were restricted to singleton pregnancies who had nonobstetric operations between the fourth and twentieth weeks of pregnancy. Too few laparoscopic procedures were performed after 20 weeks to allow comparison. A total of 2181 laparoscopies and 1522 laparotomies met criteria for analysis. There were no significant differences between the two groups in any demographic variable. Pregnancies with operations were compared with the total population for birth weight, gestational duration, growth restriction, infant survival, and fetal malformations. On the basis of relative risks, there was an increased risk for infants in both laparoscopy and laparotomy groups to weigh < 2500 gm, to be delivered before 37 weeks, and to have an increased incidence of growth restriction compared with the total population. There was no difference between laparoscopy and laparotomy in cumulative infant survival up to 1 year (odds ratio 0.85, 95% confidence interval 0.48 to 1.51). There was no difference in the rate of fetal malformations between laparoscopy (risk ratio 1.09, 95% confidence interval 0.90 to 1.11), laparotomy (risk ratio 1.08, 95% confidence interval 0.85 to 1.11), and the total population. CONCLUSION: There is no difference in five fetal outcome variables for patients undergoing laparoscopy versus laparotomy in singleton pregnancies between 4 and 20 weeks of gestation.

Evaluating sex chromosome content of sorted human sperm samples with use of dual-color fluorescence in situ hybridization.

OBJECTIVE: Although most methods for selecting the sex of offspring by sorting spermatozoa are ineffective at shifting the ratio of Y- to X-containing cells, some commercial sources continue to offer such services. Our objective was to evaluate commercially "sorted" samples with use of dual-color fluorescence in situ hybridization and to identify variations in assessment by comparing motile and total sperm populations, donors, observers, and fluorescence in situ hybridization probes. STUDY DESIGN: Cryopreserved sperm from seven anonymous donors were processed as for insemination. Sperm cells from each total sample or motile subfraction were prepared for fluorescence in situ hybridization by incubation with disulfide-reducing agents to expand sperm nuclei. Two sets of X and Y chromosome-specific, fluorophore-labeled deoxyribonucleic acid probes were used. At least 400 nuclei from each preparation were classified independently by three blinded observers. Hybridization efficiency, aneuploidy, and sex chromosome content were evaluated in subsets of five unsorted, five female-oriented, and five male-oriented samples. Total and motile subfractions were compared with eight samples. Fluorescence in situ hybridization probes were compared in five paired unsorted samples. RESULTS: No differences were detected between washed samples and paired motile subfractions. No differences in hybridization and aneuploidy were detected between groups of sorted samples. The Y/X ratio was significantly different between the sorted groups. However, male-oriented samples had a lower Y/X ratio than female-oriented samples did. Observer and probe choice accounted for small but significant variations that did not alter conclusions about the X/Y ratio for sorted samples. CONCLUSION: In a series of 10 sorted samples from one commercial source, dual-color fluorescence in situ hybridization demonstrated a small but significant shift in the sex chromosome ratios among samples. However, this shift was opposite to that expected by the orientation of the sorted samples.