Replication stress impairs chromosome segregation and preimplantation development in human embryos.

Human cleavage-stage embryos frequently acquire chromosomal aneuploidies during mitosis due to unknown mechanisms. Here, we show that S phase at the 1-cell stage shows replication fork stalling, low fork speed, and DNA synthesis extending into G2 phase. DNA damage foci consistent with collapsed replication forks, DSBs, and incomplete replication form in G2 in an ATR- and MRE11-dependent manner, followed by spontaneous chromosome breakage and segmental aneuploidies. Entry into mitosis with incomplete replication results in chromosome breakage, whole and segmental chromosome errors, micronucleation, chromosome fragmentation, and poor embryo quality. Sites of spontaneous chromosome breakage are concordant with sites of DNA synthesis in G2 phase, locating to gene-poor regions with long neural genes, which are transcriptionally silent at this stage of development. Thus, DNA replication stress in mammalian preimplantation embryos predisposes gene-poor regions to fragility, and in particular in the human embryo, to the formation of aneuploidies, impairing developmental potential.

Optimal Combinations of Broadly Neutralizing Antibodies for Prevention and Treatment of HIV-1 Clade C Infection.

The identification of a new generation of potent broadly neutralizing HIV-1 antibodies (bnAbs) has generated substantial interest in their potential use for the prevention and/or treatment of HIV-1 infection. While combinations of bnAbs targeting distinct epitopes on the viral envelope (Env) will likely be required to overcome the extraordinary diversity of HIV-1, a key outstanding question is which bnAbs, and how many, will be needed to achieve optimal clinical benefit. We assessed the neutralizing activity of 15 bnAbs targeting four distinct epitopes of Env, including the CD4-binding site (CD4bs), the V1/V2-glycan region, the V3-glycan region, and the gp41 membrane proximal external region (MPER), against a panel of 200 acute/early clade C HIV-1 Env pseudoviruses. A mathematical model was developed that predicted neutralization by a subset of experimentally evaluated bnAb combinations with high accuracy. Using this model, we performed a comprehensive and systematic comparison of the predicted neutralizing activity of over 1,600 possible double, triple, and quadruple bnAb combinations. The most promising bnAb combinations were identified based not only on breadth and potency of neutralization, but also other relevant measures, such as the extent of complete neutralization and instantaneous inhibitory potential (IIP). By this set of criteria, triple and quadruple combinations of bnAbs were identified that were significantly more effective than the best double combinations, and further improved the probability of having multiple bnAbs simultaneously active against a given virus, a requirement that may be critical for countering escape in vivo. These results provide a rationale for advancing bnAb combinations with the best in vitro predictors of success into clinical trials for both the prevention and treatment of HIV-1 infection.

Unilateral pleural effusion as the sole clinical presentation of severe ovarian hyperstimulation syndrome: a systematic review.

The pathophysiology of isolated pleural effusion in ovarian hyperstimulation syndrome (OHSS) is not well defined. The objective of the current review is to delineate the pathophysiology, risk factors, preventive measures, and therapeutic options of isolated pleural effusion in severe OHSS. Major databases were searched until June 2016. Studies evaluating women who presented with pleural effusion as the sole extra-ovarian manifestation of severe OHSS were included. Data were extracted from 24 articles encompassing 30 reported cases. Values were expressed as mean ± SEM. Patients were young (31.5 ± 0.8 years old) and 29.1% of them were diagnosed with polycystic ovary syndrome. All the patients received human chorionic gonadotropin to trigger oocyte maturation. Estradiol level was 3110 ± 330 pg/mL on the day of the ovulatory trigger. Dyspnea was the presenting symptom in 86.6% of the patients. Pleural effusion was predominantly on the right side (80%). Ninety percent of the patients underwent thoracentesis (4332 ± 769 mL): 66.7% exudate and 33.3% transudate. Fluid initially accumulates in the peritoneal cavity then enters the pleural space due to the pressure gradient through the thoracic duct and diaphragmatic defects, which are more common on the right side. The risk factors, prevention, and management, which are also discussed in this review, are similar to those of severe OHSS.

Unilateral Salpingectomy and Methotrexate Are Associated With a Similar Recurrence Rate of Ectopic Pregnancy in Patients Undergoing In Vitro Fertilization.

STUDY OBJECTIVE: To determine whether different treatment approaches of ectopic pregnancy (EP), particularly unilateral salpingectomy and methotrexate, affect its recurrence rate in patients undergoing in vitro fertilization (IVF). DESIGN: A retrospective cohort study (Canadian Task Force classification II-2). SETTING: An academic medical center. PATIENTS: Patients with a history of a previous EP who achieved pregnancy after IVF cycles between January 2004 and August 2015 were included. The recurrence rate of EP was compared between patients who underwent different treatment approaches for a previous EP. INTERVENTIONS: IVF. MEASUREMENTS AND MAIN RESULTS: A total of 594 patients were included. Seventeen patients had a recurrence of EP (2.9%). Patients with a history of ≥2 EPs were associated with a significantly higher recurrence rate of EP than those with 1 previous EP (8.5% vs. 1.8%; p = .01; odds ratio [OR] = 2.2; 95% confidence interval [CI], 1.2-4.4). Patients who underwent unilateral salpingectomy (n = 245) had a comparable recurrence rate of EP after IVF with those who received methotrexate (n = 283) (3.6% vs. 2.8%; p = .5; OR = 1.3; 95% CI, 0.4-3.4). This OR remained unchanged after adjusting for patient's age, number of previous EPs, number of transferred embryos, and peak estradiol level during stimulation (adjusted OR = 1.4; 95% CI, 0.5-3.8). None of the patients who underwent bilateral salpingectomy (n = 45) or salpingostomy (n = 21) had a recurrence of EP after IVF. CONCLUSION: The recurrence rate of EP significantly correlates with the number of previous EPs. Treatment of EP with methotrexate has a comparable recurrence rate of EP after IVF with unilateral salpingectomy. Therefore, the risk of recurrence should not be a reason to favor salpingectomy over methotrexate in this population.

Hospital for Special Surgery Pediatric Functional Activity Brief Scale predicts physical fitness testing performance.

BACKGROUND: An eight-item activity scale was recently developed and validated for use as a prognostic tool in clinical research in children and adolescents. It is unclear, however, if this brief questionnaire is predictive of quantitative metrics of physical activity and fitness. QUESTIONS/PURPOSES: The purposes of this study were to prospectively administer the Hospital for Special Surgery Pediatric Functional Activity Brief Scale to a large cohort of healthy adolescents to determine (1) if the activity scale exhibits any floor or ceiling effects; (2) if scores on the activity scale are correlated with standardized physical fitness metrics; and if so, (3) to determine the discrimination ability of the activity scale to differentiate between adolescents with healthy or unhealthy levels of aerobic capacity and calculate an appropriate cutoff value for its use as a screening tool. METHODS: One hundred eighty-two adolescents (mean, 15.3 years old) prospectively completed the activity scale and four standardized metrics of physical fitness: pushups, sit-ups, shuttle run exercise (Progressive Aerobic Cardiovascular Endurance Run), and calculated VO2-max. Age, sex, and body mass index were also recorded. Pearson correlations, regression analyses, and receiver operating characteristic analyses were used to evaluate activity scale performance. RESULTS: The activity scale did not exhibit any floor or ceiling effects. Pushups (ρ = 0.28), sit-ups (ρ = 0.23), performance on the Progressive Aerobic Cardiovascular Endurance Run (ρ = 0.44), and VO2-max (ρ = 0.43) were all positively correlated with the activity scale score (Pearson correlations, all p < 0.001). Receiver operating characteristic analysis revealed that those with an activity score of ≤ 14 were at higher risk of having low levels of aerobic capacity. CONCLUSIONS: In the current study, activity score was free of floor and ceiling effects and predictive of all four physical fitness metrics. An activity score of ≤ 14 was associated with at-risk aerobic capacity previously shown to be associated with an increased risk of metabolic syndrome. This study is the first to prospectively validate an activity questionnaire against quantitative physical fitness assessments and provides further evidence substantiating its use in outcomes research and screening for healthy levels of childhood activity and fitness. LEVEL OF EVIDENCE: Level I, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Variability in the relationship between the distal femoral mechanical and anatomical axes in patients undergoing primary total knee arthroplasty.

Currently, an intramedullary (IM) guide is often used for performing the distal femoral resection in total knee arthroplasty (TKA). However, this method assumes that in most patients, the distal femoral mechanical-anatomical angle (FMAA) is 5°. Preoperative, standing, AP hip-to-ankle radiographs were reviewed in 493 patients undergoing primary TKA, and the FMAA was digitally measured. Correlation coefficients relative to several radiographic measurements, along with demographic variables, were performed. A significant number of patients (28.6%) had an FMAA outside the range of 5° ± 2° (range 2.0°-9.6°). The only measurement demonstrating a fair/moderate correlation with the FMAA was the neck-shaft angle (r = -0.55). Using an IM resection guide, without obtaining AP hip-to-ankle radiographs to determine each patient's true FMAA, may lead to malalignment of the femoral component.

Optimal parameters for determining the LH surge in natural cycle frozen-thawed embryo transfers.

BACKGROUND: There is no consensus on the exact parameters that define the LH surge for natural cycle frozen-thawed embryo transfers (NC-FET). Accurately determining the LH surge would affect the timing, and subsequently the success rates, of embryo transfer. Therefore, the aim of this study was to delineate the optimal levels and relationship for luteinizing hormone (LH) and estradiol in an effort to optimally identify the LH surge in NC-FET. METHODS: It is a retrospective study that was performed in an academic medical center. Patients who underwent blastocyst NC-FET who either had preimplantation genetic screening (PGS) or were <35 years old but did not undergo PGS (non-PGS) were included in separate analyses. They were divided into two groups: Group A included patients whose LH surge was defined as the first attainment of LH ≥ 17 IU/L during the follicular phase with a ≥30% drop in estradiol levels the following day; group B encompassed patients whose LH level continued to rise and the surge was defined as the highest serum LH level occurring a day after LH ≥ 17 IU/L despite a ≥ 30% drop in estradiol levels. The main outcomes measures were implantation and live birth rates. RESULTS: Four hundred-seven non-PGS and 284 PGS NC-FET were included. Among non-PGS cycles, group A was associated with significantly higher implantation rates (48.7% vs. 38.1%) and live birth rates (52.9% vs. 40.1%) compared to group B. In contrast, group A and B had comparable live birth rates among PGS cycles. CONCLUSIONS: Among non-PGS cycles, measuring LH and estradiol levels the day after an LH ≥ 17 IU/L and defining the surge as the first day of LH ≥ 17 IU/L in the context of a ≥ 30% drop in estradiol the following day was associated with better NC-FET outcomes than defining the surge as the day representing the highest serum LH level despite a ≥30% drop in estradiol levels.

Morphologic grading of euploid blastocysts influences implantation and ongoing pregnancy rates.

OBJECTIVE: To determine whether blastocyst grading can predict pregnancy outcomes in the frozen-thawed embryo transfer (FET) of euploid blastocysts. DESIGN: Retrospective cohort study. SETTING: Academic medical center. PATIENT(S): Women who underwent FET of euploid embryo(s) between January 2013 and December 2015, with blastocysts were divided into four groups based on their morphologic grading before cryopreservation: excellent (≥3AA), good (3-6AB, 3-6BA, 1-2AA), average (3-6BB, 3-6AC, 3-6CA, 1-2AB, 1-2BA), and poor (1-6BC, 1-6CB, 1-6CC, 1-2BB). INTERVENTION(S): FET. MAIN OUTCOMES MEASURE(S): Ongoing pregnancy rate (OPR). RESULT(S): A total of 417 FET cycles (477 embryos) were included. Excellent-quality embryos (n = 38) yielded a statistically significantly higher OPR than poor-quality embryos (n = 106) (84.2% vs. 35.8%; adjusted odds ratio 11.0; 95% confidence interval, 3.8-32.1) and average-quality embryos (n = 197) (84.2% vs. 55.8%; adjusted odds ratio 4.8; 95% confidence interval, 1.7-13.3). Good-quality embryos (n = 76) were associated with a statistically significantly higher OPR than poor-quality embryos (61.8% vs. 35.8%). These odds ratios were adjusted for patient's age, body mass index, number of transferred embryos, type of frozen cycle, peak endometrial thickness, day of trophectoderm biopsy (5 or 6), and total number of euploid embryos for each patient. An inner cell mass grade of A yielded a statistically significantly higher OPR than ICM grade C (76.2% vs. 13.5%) or grade B (76.2% vs. 53.6%) after controlling for all confounders. CONCLUSION(S): Contrary to prior published studies, the current data suggest that blastocyst morphologic grading and particularly inner cell mass grade is a useful predictor of OPR per euploid embryo. Morphologic grading should be used to help in the selection among euploid blastocysts.

Airport metal detector activation is rare after posterior spinal fusion in children with scoliosis.

PURPOSE: Since the September 11, 2001 terrorist attacks on the World Trade Center in New York City, travel security has become an ever-increasing priority in the United States. Frequent parent and patient inquiry and recent literature reports have generated interest in the impact of heightened security measures on patients with orthopaedic implants, and have indicated increasing rates of metal detector triggering. There are no reports to date, however, evaluating children and adolescents who have undergone posterior spinal fusion for scoliosis, so responses to patient and parent inquiries are not data-driven. The purpose of this study is to determine the frequency of airport metal detector triggering by patients who have had posterior-only spinal fusion and to characterise any potential predictors of metal detector activation. METHODS: A cross-sectional study was performed by interviewing 90 patients who underwent posterior-only spinal fusion for a diagnosis of juvenile or adolescent idiopathic scoliosis and have travelled by air in the past year. Demographic, clinical and surgical instrumentation data were collected and evaluated, along with patients' reports of airport metal detector triggering and subsequent screening procedures. RESULTS: Five patients with stainless steel instrumentation (5.6 % of the cohort) triggered an airport walkthrough metal detector, and an additional five patients who did not trigger an airport detector triggered a handheld detector at a different venue. All patients who triggered an airport metal detector had stainless steel instrumentation implanted prior to 2008, and no patient with titanium instrumentation triggered any detector in any venue. All trigger events required subsequent screening procedures, even when an implant card was presented. CONCLUSIONS: In this cohort of children and adolescents with posterior spinal instrumentation, airport walkthrough metal detector triggering was a rare event. Therefore, we advise patients and families with planned posterior scoliosis fusions using titanium instrumentation that airport detection risk is essentially non-existent, and only rare for those with planned stainless steel instrumentation. We no longer issue implant cards postoperatively, as these did not prevent further screening procedures in this cohort. LEVEL OF EVIDENCE: Prognostic level 2. STUDY DESIGN: cross-sectional.

Development and validation of a pediatric sports activity rating scale: the Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS).

BACKGROUND: Having simple and reliable validated outcome measures is vital to conducting high-quality outcomes research in the field of orthopaedic surgery. Activity level is a key prognostic variable for patients with sports injuries. There is a paucity of such activity scales for children and adolescents who are otherwise healthy and athletically active. In addition to frequency and intensity of athletic activity, level of play and coach/trainer supervision are important variables unique to children and adolescents that are not captured in available adult scoring systems. PURPOSE: To create and validate a concise and comprehensive activity rating scale for athletically active children and adolescents 10 to 18 years of age. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: Item generation was performed with a panel of orthopaedic surgeons and adolescent athletes. Item reduction, pilot testing and scale refinement resulted in a final 8-item instrument, the Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS). Existing methods were used to determine reliability and validation. The Flesch-Kincaid score was calculated at a 6.6th-grade reading level (approximately 13 years old); therefore, although all subjects provided their own answers, parents were allowed to assist children younger than 13 years with reading the questionnaire. RESULTS: Scale reliability was excellent (test-retest reliability, intraclass correlation coefficient = 0.91; internal consistency, Cronbach alpha = .914), and there were no floor or ceiling effects. There was also robust construct validity: Convergent validity testing revealed positive correlations between the HSS Pedi-FABS and level of competition in athletic activity, number of reported hours of athletic activity per week, and existing comparable adult and pediatric scales. Discriminant validity was shown with age, body mass index, and type of sport as measured by the Daniel scale. CONCLUSION: The 8-item HSS Pedi-FABS can be used to reliably and accurately evaluate activity level as a prognostic variable for clinical research studies. It is a simple, reliable, and valid metric to assess activity in children and adolescents 10 to 18 years of age. This instrument will lead to better evaluation of posttreatment outcomes and patient-reported activity for child and adolescent athletes.

Gold Nanopyramids Assembled into High-Order Stacks Exhibit Increased SERS Response.

This Letter describes how gold pyramidal nanoshells (nanopyramids) can be assembled into low- and high-order structures by varying the rate of solvent evaporation and surface wettability. Single-particle and individual-cluster dark field scattering spectra on isolated, dimers and trimers of nanopyramids were compared. We found that the short wavelength resonances blue-shifted as the particles assembled; the magnitude of this shift was greater for high-order structures. To test which assembled architecture supported a larger Raman-active volume, we compared their surface enhanced Raman scattering (SERS) response of the resonant Raman molecule methylene blue (λ(ex) = 633 nm). We discovered that high-order structures exhibited more Raman scattering compared to low-order assemblies. Finite-difference time-domain modeling of nanopyramid assemblies revealed that the highest electromagnetic field intensities were localized between adjacent particle faces, a result that was consistent with the SERS observations. Thus, the local spatial arrangement of the same number of nanoparticles in assembled clusters is an important design parameter for optimizing nanoparticle-based SERS sensors.