P–282 A time lapse analysis of 36,671 embryos to compare the incidence of early stage abnormal cleavage events in ICSI and IVF derived embryos

Study question

Is this incidence of early stage abnormal cleavage events different between embryos created following ICSI compared with IVF?

Summary answer

Embryos derived from ICSI are more likely to exhibit abnormal cleavage compared with those from IVF. This difference is most marked in women ≥35 years.

What is known already

Time lapse imaging (TLI) has been instrumental in allowing detailed annotation of early embryo development to provide an objective aid for embryo selection in ART cycles. Amongst several abnormal cleavage events reported, rapid cleavage and multichotomous mitosis/direct cleavage, during the first days after fertilisation have been demonstrated to be associated with lower blastulation rates, reduced implantation potential, increased aneuploidy and poor pregnancy outcomes. With ICSI being utilised commonly, and being the insemination method of choice in some clinics, the incidence of abnormal cleavage was investigated in association with insemination method, ICSI or IVF.

Study design, size, duration

The incidence of abnormal cleavage events was evaluated in a large multicentre retrospective analysis of 36,671 embryos from 6689 patients treated in 8 IVF clinics enabled with time lapse imaging, between 2011 - 2019. This constituted 10931 IVF embryos and 25740 ICSI embryos.

Participants/materials, setting, methods

Following ICSI or after IVF fertilisation check, embryos were time-lapse imaged every 10 minutes and annotated using the EmbryoScope. Second cell cycle durations were calculated as follows: time to reach 3-cell (t3) from 2-cell (t2) (t3-t2 = cc2). These were analysed using a welch t-test as three groups of abnormal cleavage: direct cleavage/trichotomous mitosis (DC) - where cc2=0 hours(h), rapid cleavage within 2h (R2) - where 0<cc2<2h and rapid cleavage between 2–5h (R5) where 2h<cc2<5h.

Main results and the role of chance

The incidence of DC, R2 and R5 in the whole cohort of embryos was 5%, 8% and 9% respectively. In the subpopulation of IVF embryos the incidence of DC, R2 and R5 was 4%, 8% and 9% respectively. In the subpopulation of ICSI embryos the incidence of DC, R2 and R5 was 6%, 8% and 9% respectively. The incidence of DC was significantly higher in ICSI embryos compared with IVF (p < 0.001) whilst R2 and R5 were the same. ICSI derived embryos had a mean (± SE) cc2 value of 9.39 ± 0.03h, compared with 9.56 ± 0.05h for IVF embryos (p < 0.0038). Examination of data split by maternal age demonstrated that ICSI oocytes from women of advanced maternal age (≥35) also had significantly more embryos exhibiting rapid cleavages R2 and R5 than IVF oocytes (p < 0.007). There were no significant differences however, in rates of abnormal cleavages between ICSI and IVF in embryos from women aged <30 (p = 0.06).

Male-factor diagnoses showed no significant differences in abnormal cleavage values between ICSI or IVF in all three abnormal cleavage categories.

Limitations, reasons for caution

This analysis could not control for all potential confounders therefore it is possible that the increased abnormal cleavages observed in this investigation are a result of another, or combination of factors. Despite quality assurance programs being in place across all clinics, there is a risk of annotation bias.

Wider implications of the findings: There is a higher incidence of early abnormal cleavage in embryos derived from ICSI, particularly in those from women of increased age and this research may help elucidate the reasons for this and add to the debate regarding the appropriateness of the increasing use of ICSI.

Trial registration number

Not applicable

Long-term results of tripolar constrained total hip arthroplasty in revision hip arthroplasty

Aims

We investigated the long-term performance of the Tripolar Trident acetabular component used for recurrent dislocation in revision total hip arthroplasty. We assessed: 1) rate of re-dislocation; 2) incidence of complications requiring re-operation; and 3) Western Ontario and McMaster Universities osteoarthritis index (WOMAC) pain and functional scores.

Patients and Methods

We retrospectively identified 111 patients who had 113 revision tripolar constrained liners between 1994 and 2008. All patients had undergone revision hip arthroplasty before the constrained liner was used: 13 after the first revision, 17 after the second, 38 after the third, and 45 after more than three revisions. A total of 75 hips (73 patients) were treated with Tripolar liners due to recurrent instability with abductor deficiency, In addition, six patients had associated cerebral palsy, four had poliomyelitis, two had multiple sclerosis, two had spina bifida, two had spondyloepiphyseal dysplasia, one had previous reversal of an arthrodesis, and 21 had proximal femoral replacements. The mean age of patients at time of Tripolar insertions was 72 years (53 to 89); there were 69 female patients (two bilateral) and 42 male patients. All patients were followed up for a mean of 15 years (10 to 24). Overall, 55 patients (57 hips) died between April 2011 and February 2018, at a mean of 167 months (122 to 217) following their tripolar liner implantation. We extracted demographics, implant data, rate of dislocations, and incidence of other complications.

Results

At ten years, the Kaplan–Meier survivorship for dislocation was 95.6% (95% confidence interval (CI) 90 to 98), with 101 patients at risk. At 20 years, the survivorship for dislocation was 90.6% (95% CI 81.0 to 95.5), with one patient at risk. Eight patients (7.2%) had a dislocation of their constrained liners. At ten years, the survival to any event was 89.4% (95% CI 82 to 93.8), with 96 patients at risk. At 20 years, the survival to any event was 82.5% (95% CI 71.9 to 89.3), with one patient at risk. Five hips (4.4%) had deep infection. Two patients (1.8%) developed dissociated constraining rings with pain but without dislocation, which required re-operation. Two patients (1.8%) had periprosthetic femoral fractures, without dislocation, that were treated by revision stems along with exchange of the well-functioning constrained liners.

Conclusion

Constrained tripolar liners used at revision hip arthroplasty provided favourable results in the long term for treatment of recurrent dislocation and for patients at high risk of dislocation. Cite this article: Bone Joint J 2019;101-B(6 Supple B):123–126.

High-tension electrical burns: special problems and their management

High tension burn injuries comprise 1% of admissions to burns units and have a high incidence of mortality or amputation of an extremity in patients who survive. A dichotomy regarding treatment rationale for high tension electrically injured patients exists and is supported by two separate views of the pathophysiology of the injury. One view contends that the full extent of the injury occurs at the time of injury and this concept is used to support a philosophy of early radical debridement and reconstruction. Another view is that an element of chronicity exists in wound development and that serial examinations and debridements may be required prior to definitive reconstruction. The treatment rationale presented by the authors is that the high complication rate associated with these injuries, including partial or complete flap failure, as well as the need to preserve vital tissue justifies a cautious reconstructive approach similar to that used in high velocity lower limb injuries with serial examinations and debridements taking place prior to definitive reconstruction. A historical overview and discussion of some of the unique features of high tension electrical injuries is presented and used to support the authors’ philosophy of management.

New avenues for phase matching in nonlinear hyperbolic metamaterials

Nonlinear optical processes, which are of paramount importance in science and technology, involve the generation of new frequencies. This requires phase matching to avoid that light generated at different positions interferes destructively. Of the two original approaches to achieve this, one relies on birefringence in optical crystals, and is therefore limited by the dispersion of naturally occurring materials, whereas the other, quasi-phase-matching, requires direct modulation of material properties, which is not universally possible. To overcome these limitations, we propose to exploit the unique dispersion afforded by hyperbolic metamaterials, where the refractive index can be arbitrarily large. We systematically analyse the ensuing opportunities and demonstrate that hyperbolic phase matching can be achieved with a wide range of material parameters, offering access to the use of nonlinear media for which phase matching cannot be achieved by other means. With the rapid development in the fabrication of hyperbolic metamaterials, our approach is destined to bring significant advantages over conventional techniques for the phase matching of a variety of nonlinear processes.

Prognostic value of histologic grading for feline mammary carcinoma: a retrospective survival analysis

Feline mammary carcinoma is highly malignant and generally associated with a poor prognosis, although studies suggest the range of survival times in affected cats is broad. Histologic grading of these tumors is achieved using the Elston and Ellis system, originally developed for human breast cancer. In cats, however, classification using this method has variable prognostic value. Therefore, objectives of this study were (1) to evaluate the Elston and Ellis grading system for feline mammary carcinoma in a predominantly spayed population and (2) to determine whether modification of this system or development of a novel system improved the prognostic value of histologic grading. Survey data and histologic features for 108 carcinomas from 97 cats were analyzed with respect to overall survival. Elston and Ellis grading failed to correlate significantly with overall survival. Using multivariable analysis, lymphovascular invasion, nuclear form, and mitotic count each demonstrated independent prognostic significance (P = .008, <.001, and .004, respectively). Modifications of the Elston and Ellis system and a novel grading system were proposed based on these results; all showed significant correlation with overall survival (P < .001). Median survival times were 27, 29, or 31 months for grade I; 14, 12, or 14 months for grade II; and 13, 5, or 8 months for grade III carcinomas using the mitotic-modified Elston and Ellis, the revised Elston and Ellis, or the novel grading system, respectively. Based on this retrospective study, adoption of the species-specific systems as proposed here may improve the prognostic value of histologic grading for feline mammary carcinoma.

X-ray fluorescence imaging reveals subcellular biometal disturbances in a childhood neurodegenerative disorder

Biometals such as zinc, iron, copper and calcium play key roles in diverse physiological processes in the brain, but can be toxic in excess. A hallmark of neurodegeneration is a failure of homeostatic mechanisms controlling the concentration and distribution of these elements, resulting in overload, deficiency or mislocalization. A major roadblock to understanding the impact of altered biometal homeostasis in neurodegenerative disease is the lack of rapid, specific and sensitive techniques capable of providing quantitative subcellular information on biometal homeostasis in situ. Recent advances in X-ray fluorescence detectors have provided an opportunity to rapidly measure biometal content at subcellular resolution in cell populations using X-ray Fluorescence Microscopy (XFM). We applied this approach to investigate subcellular biometal homeostasis in a cerebellar cell line isolated from a natural mouse model of a childhood neurodegenerative disorder, the CLN6 form of neuronal ceroid lipofuscinosis, commonly known as Batten disease. Despite no global changes to whole cell concentrations of zinc or calcium, XFM revealed significant subcellular mislocalization of these important biological second messengers in cerebellar Cln6nclf (CbCln6nclf ) cells. XFM revealed that nuclear-to-cytoplasmic trafficking of zinc was severely perturbed in diseased cells and the subcellular distribution of calcium was drastically altered in CbCln6nclf cells. Subtle differences in the zinc K-edge X-ray Absorption Near Edge Structure (XANES) spectra of control and CbCln6nclf cells suggested that impaired zinc homeostasis may be associated with an altered ligand set in CbCln6nclf cells. Importantly, a zinc-complex, ZnII(atsm), restored the nuclear-to-cytoplasmic zinc ratios in CbCln6nclf cells via nuclear zinc delivery, and restored the relationship between subcellular zinc and calcium levels to that observed in healthy control cells. ZnII(atsm) treatment also resulted in a reduction in the number of calcium-rich puncta observed in CbCln6nclf cells. This study highlights the complementarities of bulk and single cell analysis of metal content for understanding disease states. We demonstrate the utility and broad applicability of XFM for subcellular analysis of perturbed biometal metabolism and mechanism of action studies for novel therapeutics to target neurodegeneration.

The association between postprandial urinary C-peptide creatinine ratio and the treatment response to liraglutide: a multi-centre observational study

AIMS

The response to glucagon-like peptide 1 receptor agonist treatment may be influenced by endogenous β-cell function. We investigated whether urinary C-peptide creatinine ratio assessed before or during liraglutide treatment was associated with treatment response.

METHODS

A single, outpatient urine sample for urinary C-peptide creatinine ratio was collected 2 h after the largest meal of the day among two separate groups: (1) subjects initiating liraglutide (0.6 → 1.2 mg daily) or (2) subjects already treated with liraglutide for 20-32 weeks. The associations between pretreatment and on-treatment urinary C-peptide creatinine ratio and HbA1c change at 32 weeks were assessed using univariate and multivariate analyses (the ratio was logarithm transformed for multivariate analyses). Changes in HbA1c according to pretreatment urinary C-peptide creatinine ratio quartiles are shown.

RESULTS

One hundred and sixteen subjects (70 pretreatment, 46 on treatment) with Type 2 diabetes from 10 diabetes centres were studied. In univariate analyses, neither pretreatment nor on-treatment urinary C-peptide creatinine ratio correlated with HbA1c change (Spearman rank correlation coefficient, r = -0.17, P = 0.17 and r = -0.20, P = 0.19, respectively). In multi-linear regression analyses, entering baseline HbA1c and log urinary C-peptide creatinine ratio, pretreatment and on-treatment log urinary C-peptide creatinine ratio became significantly associated with HbA1c change (P = 0.048 and P = 0.040, respectively). Mean (sd) HbA1c changes from baseline in quartiles 1 to 4 of pretreatment urinary C-peptide creatinine ratio were -3 ± 17 mmol/mol (-0.3 ± 1.6%) (P = 0.52), -12 ± 15 mmol/mol (-1.1 ± 1.4%) (P = 0.003), -11 ± 13 mmol/mol (-1.0 ± 1.2%) (P = 0.002) and -12±17 mmol/mol (-1.1±1.6%) (P=0.016), respectively.

CONCLUSIONS

Postprandial urinary C-peptide creatinine ratios before and during liraglutide treatment were weakly associated with the glycaemic response to treatment. Low pretreatment urinary C-peptide creatinine ratio may be more useful than higher values by predicting poorer glycaemic response.

Histologic Characteristics and KIT Staining Patterns of Equine Cutaneous Mast Cell Tumors

Mast cell tumors are uncommon in horses and typically have a benign clinical course, but there are occasional reports of more aggressive behavior. The objective of this study was to review histologic features and KIT expression patterns of 72 previously diagnosed equine cutaneous mast cell tumors to determine if either is associated with clinical outcomes. Biopsy specimens were reviewed using histologic criteria derived from grading schemes, and KIT antibody expression patterns used in canine tumors and surveys were sent to referring veterinarians for follow-up clinical data. Arabians were overrepresented relative to the reference population. Most tumors were well differentiated with low mitotic rates (96%), and aberrant KIT staining patterns, as described in dogs, were uncommonly identified (12%). Associated clinical disease was uncommon and no tumors exhibited malignant behavior. Overall, KIT staining pattern and histologic features were not associated with poor clinical outcome or abnormal tumor behavior.

Use of a tissue expander as a radio-protective spacer with a latissimus dorsi flap in the management of a peripheral primitive neuroectodermal tumour (pPNET)

Peripheral primitive neuroectodermal tumours (pPNET) are aggressive neoplasms that require radical surgical resection with adjuvant chemotherapy and radiotherapy. A pPNET of the posterior chest wall was resected with wide soft tissue margins in a 14 year old male. Following tumour excision a spacer device was positioned in the retroperitoneum adjacent to the ipsilateral left kidney displacing it from the planned radiotherapy field. A pedicled latissimus dorsi myocutaneous flap was used to achieve robust soft tissue cover. Ultrasound demonstrated anteromedial displacement of the left kidney with no hydronephrosis and renal function remained normal during subsequent radiotherapy. This report highlights the usefulness of a tissue expander in providing protection for vital structures during radiotherapy.

Physician perceptions and practice patterns regarding fertility preservation in hematopoietic cell transplant recipients

Physician practice variation may be a barrier to informing hematopoietic cell transplant (HCT) recipients about fertility preservation (FP) options. We surveyed HCT physicians in the United States to evaluate FP knowledge, practices, perceptions and barriers. Of the 1035 physicians invited, 185 completed a 29-item web-survey. Most respondents demonstrated knowledge of FP issues and discussed and felt comfortable discussing FP. However, only 55% referred patients to an infertility specialist. Most did not provide educational materials to patients and only 35% felt that available materials were relevant for HCT. Notable barriers to discussing FP included perception that patients were too ill to delay transplant (63%), patients were already infertile from prior therapy (92%) and time constraints (41%). Pediatric HCT physicians and physicians with access to an infertility specialist were more likely to discuss FP and to discuss FP even when prognosis was poor. On analyses that considered physician demographics, knowledge and perceptions as predictors of referral for FP, access to an infertility specialist and belief that patients were interested in FP were observed to be significant. We highlight variation in HCT physician perceptions and practices regarding FP. Physicians are generally interested in discussing fertility issues with their patients but lack educational materials.

Painful nerve injury decreases sarco-endoplasmic reticulum Ca²⁺-ATPase activity in axotomized sensory neurons

The sarco-endoplasmic reticulum Ca(2+)-ATPase (SERCA) is a critical pathway by which sensory neurons sequester cytosolic Ca(2+) and thereby maintain intracellular Ca(2+) homeostasis. We have previously demonstrated decreased intraluminal endoplasmic reticulum Ca(2+) concentration in traumatized sensory neurons. Here we examine SERCA function in dissociated sensory neurons using Fura-2 fluorometry. Blocking SERCA with thapsigargin (1 μM) increased resting [Ca(2+)](c) and prolonged recovery (τ) from transients induced by neuronal activation (elevated bath K(+)), demonstrating SERCA contributes to control of resting [Ca(2+)](c) and recovery from transient [Ca(2+)](c) elevation. To evaluate SERCA in isolation, plasma membrane Ca(2+) ATPase was blocked with pH 8.8 bath solution and mitochondrial buffering was avoided by keeping transients small (≤ 400 nM). Neurons axotomized by spinal nerve ligation (SNL) showed a slowed rate of transient recovery compared to control neurons, representing diminished SERCA function, whereas neighboring non-axotomized neurons from SNL animals were unaffected. Injury did not affect SERCA function in large neurons. Repeated depolarization prolonged transient recovery, showing that neuronal activation inhibits SERCA function. These findings suggest that injury-induced loss of SERCA function in small sensory neurons may contribute to the generation of pain following peripheral nerve injury.

Apoptosis in normal and Coxiella burnetii-infected placentas from Alaskan northern fur seals (Callorhinus ursinus)

In 2010, Coxiella burnetii was identified in 75% of northern fur seal placentas from a single rookery in Alaska, but nothing was known about the significance of this organism in the population. Although many infectious organisms cause increased cell death, C. burnetii has been shown to suppress apoptosis of the host macrophages as an intracellular survival mechanism. To determine if infection induces a similar functional change in the placenta, immunohistochemistry for antibodies to cleaved caspase-3 (activated caspase-3) and the (TDT)-mediated dUTP-digoxigenin nick end labeling (TUNEL) technique were used to compare the amount of placental apoptosis in infected and noninfected placentas. There was a statistically significant difference in the frequency of apoptotic cells between infected and uninfected placentas, with more apoptosis identified in the uninfected placentas. This finding suggests that the survival mechanism of C. burnetii in host macrophages to reduce apoptosis may also be utilized in trophoblasts. The significance of decreased trophoblastic apoptosis for the northern fur seal fetus requires further investigation.

Multiple strains of Coxiella burnetii are present in the environment of St. Paul Island, Alaska

In 2010, Coxiella burnetii was identified at a high prevalence in the placentas of Northern fur seals (Callorhinus ursinus) collected at a single rookery on St. Paul Island Alaska; an area of the United States where the agent was not known to be present. As contamination was hypothesized as a potential cause of false positives, but nothing was known about environmental C. burnetii in the region, an environmental survey was conducted to look for the prevalence and distribution of the organism on the island. While environmental prevalence was low, two strains of the organism were identified using PCR targeting the COM1 and IS1111 genes. The two strains are consistent with the organism that has been increasingly identified in marine mammals as well as a strain type more commonly found in terrestrial environments and associated with disease in humans and terrestrial animals. Further work is needed to elucidate information regarding the ecology of this organism in this region, particularly in association with the coastal environment.

On the Decay Retardant Properties of Some Tropolones

The heartwoods of tree species containing tropolone compounds in their extractive components are classed among the more durable woods. Two new tropolones, namely, alpha-thujaplicinol and pygmaein from the heartwood of Cupressus pygmaea, were also found to exhibit strong fungitoxic properties active against a number of wood-destroying fungi. The hydroxyl group appears to be the functional grouping which is largely responsible for the fungicidal action exhibited by this type of compound.