Faculty Bibliography

BACKGROUND:The development of acellular dermal matrices has revolutionized implant-based breast reconstruction. The most recent development has been the introduction of prepectoral breast reconstruction. However, concerns have been expressed related to the quality of soft-tissue coverage and infectious complications. Thus, the authors felt it prudent to perform a matched-pair analysis of clinical outcomes following prepectoral and subpectoral tissue expander placement. METHODS:A retrospective study of patients who underwent immediate breast reconstruction by means of prepectoral (group 1) and dual-plane subpectoral (group 2) tissue expander placement was performed. Patients in each group were matched for age, body mass index, history of radiotherapy, and type of acellular dermal matrix. Of note, patients in group 1 received perioperative antibiotic prophylaxis for less than 24 hours, whereas patients in group 2 received antibiotic prophylaxis for at least 1 week. RESULTS:A total of 80 patients (138 breast reconstructions) were included in the study (group 1, n = 40; group 2, n = 40). No difference in total postoperative complication rate (p = 0.356) and mastectomy skin necrosis rate (p = 1.0) was noted. Observed differences in major complications (p = 0.06), major infection (p = 0.09), and loss of reconstruction (p = 0.09) were not found to be significant. CONCLUSION/CONCLUSIONS:Immediate prepectoral tissue expander insertion with anterior acellular dermal matrix coverage and less than 24 hours of antibiotic prophylaxis is safe and compares favorably to subpectoral tissue expander placement with an inferior acellular dermal matrix sling and a prolonged course of antibiotics. CLINICAL QUESTION/LEVEL OF EVIDENCE/METHODS:Therapeutic, III.

Bacterial dysbiosis accompanies carcinogenesis in malignancies such as colon and liver cancer, and has recently been implicated in the pathogenesis of pancreatic ductal adenocarcinoma (PDA)¹. However, the mycobiome has not been clearly implicated in tumorigenesis. Here we show that fungi migrate from the gut lumen to the pancreas, and that this is implicated in the pathogenesis of PDA. PDA tumours in humans and mouse models of this cancer displayed an increase in fungi of about 3,000-fold compared to normal pancreatic tissue. The composition of the mycobiome of PDA tumours was distinct from that of the gut or normal pancreas on the basis of alpha- and beta-diversity indices. Specifically, the fungal community that infiltrated PDA tumours was markedly enriched for Malassezia spp. in both mice and humans. Ablation of the mycobiome was protective against tumour growth in slowly progressive and invasive models of PDA, and repopulation with a Malassezia species-but not species in the genera Candida, Saccharomyces or Aspergillus-accelerated oncogenesis. We also discovered that ligation of mannose-binding lectin (MBL), which binds to glycans of the fungal wall to activate the complement cascade, was required for oncogenic progression, whereas deletion of MBL or C3 in the extratumoral compartment-or knockdown of C3aR in tumour cells-were both protective against tumour growth. In addition, reprogramming of the mycobiome did not alter the progression of PDA in Mbl- (also known as Mbl2) or C3-deficient mice. Collectively, our work shows that pathogenic fungi promote PDA by driving the complement cascade through the activation of MBL.

The apical surface of the terminally differentiated mammalian urothelial umbrella cell is mechanically stable and highly impermeable, in part due its coverage by urothelial plaques consisting of 2D-crystals of uroplakin particles. The mechanism for regulating the uroplakin/plaque level is unclear. We found that genetic ablation of the highly tissue-specific sorting nexin Snx31, which localizes to plaques lining the multivesicular bodies (MVBs) in urothelial umbrella cells, abolishes MVBs suggesting that Snx31 plays a role in stabilizing the MVB-associated plaques by allowing them to achieve a greater curvature. Strikingly, Snx31 ablation also induces a massive accumulation of uroplakin-containing mitochondria-derived lipid droplets (LDs), which mediate uroplakin degradation via autophagy/lipophagy, leading to the loss of apical and fusiform vesicle plaques. These results suggest that MVBs play an active role in suppressing the excessive/wasteful endocytic degradation of uroplakins. Failure of this suppression mechanism triggers the formation of mitochondrial LDs so that excessive uroplakin membranes can be sequestered and degraded. Since mitochondrial LD formation, which occurs at a low level in normal urothelium, can also be induced by disturbance in uroplakin polymerization due to individual uroplakin-knockout and by arsenite, a bladder carcinogen, this pathway may represent an inducible, versatile urothelial detoxification mechanism. [Media: see text] [Media: see text] [Media: see text].

Histone post-translational modifications are key gene expression regulators, but their rapid dynamics during development remain difficult to capture. We applied a Fab-based live endogenous modification labeling technique to monitor the changes in histone modification levels during zygotic genome activation (ZGA) in living zebrafish embryos. Among various histone modifications, H3 Lys27 acetylation (H3K27ac) exhibited most drastic changes, accumulating in two nuclear foci in the 64- to 1k-cell-stage embryos. The elongating form of RNA polymerase II, which is phosphorylated at Ser2 in heptad repeats within the C-terminal domain (RNAP2 Ser2ph), and miR-430 transcripts were also concentrated in foci closely associated with H3K27ac. When treated with α-amanitin to inhibit transcription or JQ-1 to inhibit binding of acetyl-reader proteins, H3K27ac foci still appeared but RNAP2 Ser2ph and miR-430 morpholino were not concentrated in foci, suggesting that H3K27ac precedes active transcription during ZGA. We anticipate that the method presented here could be applied to a variety of developmental processes in any model and non-model organisms.

BACKGROUND:Despite robust cholesterol lowering, cardiovascular disease risk remains increased in patients with diabetes mellitus. Consistent with this, diabetes mellitus impairs atherosclerosis regression after cholesterol lowering in humans and mice. In mice, this is attributed in part to hyperglycemia-induced monocytosis, which increases monocyte entry into plaques despite cholesterol lowering. In addition, diabetes mellitus skews plaque macrophages toward an atherogenic inflammatory M1 phenotype instead of toward the atherosclerosis-resolving M2 state typical with cholesterol lowering. Functional high-density lipoprotein (HDL), typically low in patients with diabetes mellitus, reduces monocyte precursor proliferation in murine bone marrow and has anti-inflammatory effects on human and murine macrophages. Our study aimed to test whether raising functional HDL levels in diabetic mice prevents monocytosis, reduces the quantity and inflammation of plaque macrophages, and enhances atherosclerosis regression after cholesterol lowering. METHODS:mice were transplanted into either wild-type, diabetic wild-type, or diabetic mice transgenic for human apolipoprotein AI, which have elevated functional HDL. Recipient mice all had low levels of low-density lipoprotein cholesterol to promote plaque regression. After 2 weeks, plaques in recipient mouse aortic grafts were examined. RESULTS:Diabetic wild-type mice had impaired atherosclerosis regression, which was normalized by raising HDL levels. This benefit was linked to suppressed hyperglycemia-driven myelopoiesis, monocytosis, and neutrophilia. Increased HDL improved cholesterol efflux from bone marrow progenitors, suppressing their proliferation and monocyte and neutrophil production capacity. In addition to reducing circulating monocytes available for recruitment into plaques, in the diabetic milieu, HDL suppressed the general recruitability of monocytes to inflammatory sites and promoted plaque macrophage polarization to the M2, atherosclerosis-resolving state. There was also a decrease in plaque neutrophil extracellular traps, which are atherogenic and increased by diabetes mellitus. CONCLUSIONS:Raising apolipoprotein AI and functional levels of HDL promotes multiple favorable changes in the production of monocytes and neutrophils and in the inflammatory environment of atherosclerotic plaques of diabetic mice after cholesterol lowering and may represent a novel approach to reduce cardiovascular disease risk in people with diabetes mellitus.

Atherosclerosis is a progressive vascular disease triggered by interplay between abnormal shear stress and endothelial lipid retention. A combination of these and, potentially, other factors leads to a chronic inflammatory response in the vessel wall, which is thought to be responsible for disease progression characterized by a buildup of atherosclerotic plaques. Yet molecular events responsible for maintenance of plaque inflammation and plaque growth have not been fully defined. Here we show that endothelial TGFβ signaling is one of the primary drivers of atherosclerosis-associated vascular inflammation. Inhibition of endothelial TGFβ signaling in hyperlipidemic mice reduces vessel wall inflammation and vascular permeability and leads to arrest of disease progression and regression of established lesions. These pro-inflammatory effects of endothelial TGFβ signaling are in stark contrast with its effects in other cell types and identify it as an important driver of atherosclerotic plaque growth and show the potential of cell-type specific therapeutic intervention aimed at control of this disease.

Objective: Retrotransposons are a group of abundant, repetitive sequences, which originated from ancient retroviral infections of our ancestral genomes. They are silenced by epigenetic marks throughout most of life, but become activated during early embryo development, with reprogramming of the epigenome. Some retrotransposons play regulatory roles during early development. Non-Long Terminal Repeat (LTR) retrotransposons (e.g. LINE-1) regulate gene expression during early mouse embryo development. LTR retrotransposons, such as the human endogenous retrovirus HERV-W and HERV-FRD (Syncytin-1 and Syncytin-2), mediate placentation¹. We hypothesized that aneuploidy, which disrupts implantation, would affect expression of retrotransposons during early human development.
Design(s): Prospective laboratory study.
Material(s) and Method(s): Blastocysts donated by patients who underwent IVF/PGT-A at NYU Langone FC were thawed, stripped of zona pellucidae by laser (to remove sperm or cumulus) and their genomic DNA and mRNA separated by the G&Tseq protocol² with modifications. mRNA expression and gene copy number were measured by RT-qPCR and qPCR using Bio-Rad CFX96 thermocycler and iQ SYBY Green mix, and the DELTADELTACq method was used to express their levels relative to GAPDH and 5S RNA, respectively. Data were analyzed by Mann Whitney U test and Student's T-test with GraphPad Prism 8 software.
Result(s): Syncytin-1 was expressed in all human embryos, but its expression in euploid embryos (n=2) was significantly higher than in aneuploid embryos (n=6) (median 1.943 vs 0.316, P= 0.0019). Expression of Syncytin-2 also was extremely higher in euploid compared to aneuploid embryos (median 2.155 vs. 0.1124, P= 0.0003). The copy number of ALU sequences in aneuploid embryos was greater than in euploid embryos (mean 0.943+/-0.067 vs 0.807+/-0.0716, T-test P=0.0486), but LINE1 copy number or expression did not differ between euploid and aneuploid embryos (mean 0.787+/-0.069 vs 0.904+/-0.094, T-test P= 0.1778).
Conclusion(s): We compared expression of a number of retrotransposons between euploid and aneuploid human blastocysts, and discovered that the human endogenous retrovirus, Syncytin-1 and Syncytine-2, are markedly decreased in aneuploid compared to euploid embryos. Given the crucial role of Syncytins in formation of human placenta, our data provide a possible mechanism of implantation failure in euploid embryos, and suggest a possible biomarker for implantation. References: 1. Soygur B, Moore H. Expression of Syncytin 1 (HERV-W), in the preimplantation human blastocyst, embryonic stem cells and trophoblast cells derived in vitro. Hum Reprod. 2016 Jul; 31(7):1455-61. 2. Macaulay IC, Teng MJ, Haerty W, Kumar P, Ponting CP, Voet T. Separation and parallel sequencing of the genomes and transcriptomes of single cells using G&T-seq. Nat Protoc. 2016 Nov; 11(11):2081-103.
Copyright

Objective: Posthumous assisted reproduction (PAR) raises complicated ethical and legal issues. ASRM recommends that assisted reproductive technology (ART) and fertility preservation (FP) programs develop written policies regarding cases of PAR, though little is known about adoption of such policies and how they have been implemented. Our objective was to assess the presence and content of policies toward PAR using oocytes and embryos amongSociety for Assisted Reproductive Technology (SART) member clinics in the U.S.
Design(s): Cross-sectional questionnaire-based study.
Material(s) and Method(s): Our study consists of three phases of communication: email-, postal mail-, and phone-based survey. We report on the first phase of anonymous email survey responses. Surveys were emailed to ASRM-member medical directors of all SART member clinics (n=332) during March and April 2019 using a modified Dillman Method; contact information was acquired from SART and ASRM membership data. The survey included 23 multiple-choice and 3 opened-ended questions assessing practice characteristics (practice type, location, IVF cycle volume), presence of a clinic policy towards PAR, and the content of such policy. Descriptive data are presented as %, with Fisher's exact test used where appropriate, and thematic content analysis was applied to open-ended responses.
Result(s): The first phase of the study received 39 clinic responses (12% response rate). Respondents were distributed across the U.S.; average volume of IVF cycles per year ranged from < 250 to > 1500. More than one-third (35.9%, n=14) of clinics reported participating in any cases of PAR over the past five years, and 5.1% (n=2) reported participation in more than five cases. Participation in cases of PAR was not significantly associated with practice type or IVF cycle volume (p>0.05). 57.9% (n=22) had written policies towards PAR using oocytes or embryos, while 36.8% (n=14) reported they did not have a policy. Practice type, IVF cycle volume, FP volume, and prior participation in cases of PAR were not significantly associated with the presence of a policy (p>0.05). Of those with a policy, 52.4% (n=11) reported they had used that policy, 66.7% (n=10) without a policy reported they had considered adopting one, and 60.0% (n=9) reported they had received a request for PAR services. Only 44% (n=15) of clinics specified that patients not expected to survive to use oocytes due to terminal illness were eligible for oocyte cryopreservation, while 50.0% (n=17) did not specify. Open-ended comments suggested need for case-by-case appraisal and firm consent polices regarding gamete disposition.
Conclusion(s): Our preliminary results suggest that SART programs are receiving an increasing number of requests for PAR services, but many SART programs lack PAR policies, and those with policies do not always follow ASRM recommendations. As PAR cases become more common, clinics should be equipped to manage the complexities of PAR. More data are needed as this study continues, and future research is needed to understand barriers to the creation and implementation of these increasingly needed policies.
Copyright

Objective: Clinical guidelines on the optimal duration of controlled ovarian stimulation and ideal follicle size were developed for fresh embryo transfer cycles. Whether these apply to freeze all cycles remain unclear. We evaluated the impact of lead follicle size and duration of stimulation on the probability of euploid embryos in women undergoing IVF/PGT-A Design: Cross-sectional study
Material(s) and Method(s): Data from 721 patients undergoing at least two cycles of COS for IVF with preimplantation genetic testing for aneuploidy (PGT-A) via Next Generation Sequencing (NGS) (1859 cycles). Mixed-effect logistic regression, which can account for correlations among repeated outcomes within sample patients, was used to evaluate the association between independent variables and probability of achieving euploid embryos. We first conducted a mixed-effect logistic regression in a univariate manner. All variables then were evaluated in a multivariate model to control for confounding effects. Significant variables to p<0.05 were retained in the final model. p-values <0.05 were considered significant. Statistical analyses were performed using "nlme" and "lme4" package from R project. Results are reported as odds ratios (OR) with 95% confidence intervals (CI).
Result(s): Increasing sum (1.034 [1.022 1.046]/p<0.001) and mean diameter (1.129 [1.046 1.219] p=0.002) of the 5 largest follicles increased the probability of forming euploid embryos. Increasing days of stimulation showed a non-significant trend toward lower chance of forming euploid embryos (0.976 [0.923 1.031]/p=0.382) (Table 1).
Conclusion(s): Allowing the lead follicles to exceed 18mm increases the total number of euploid embryos formed per cycle, presumably by enabling retrieval of additional mature oocytes. Evidence of a detrimental effect of excessive follicle size was not evident in our study, though the number of cycles with follicles exceeding 24 mm was limited. The non-significant trend toward decreased euploid embryos following prolonged stimulation may reflect the effects of poor responders. [Figure presented]
Copyright