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Proceedings of the New York University School of Medicine Reproductive Ethics Conference: Challenges and Solutions [Letter]
Sampson, Amani; Sutter, Megan; Caplan, Arthur L; Keefe, David L; Quinn, Gwendolyn P
PMID: 31346937
ISSN: 1573-7330
CID: 3988242
Telomeres and genomic instability during early development
Keefe, David L
Genomic instability is widespread during early embryo development. Aneuploidy, mosaicism, and copy number variants (CNVs) commonly appear in human preimplantation embryos. Both age-dependent meiotic aneuploidy and age-independent mitotic aneuploidy and CNVs occur In human embryos. Telomere attrition, which contributes to genomic instability in somatic cells, also may promote genomic instability in preimplantation embryos. Telomere dynamics during gametogenesis are strikingly dimorphic between females and males. Sperm telomeres lengthen with advancing paternal age, while oocyte telomeres are among the shortest in the body. Spermatogonia express telomerase activity throughout the life of the male, while oocytes and cleavage stage embryos express low or un-measureable levels of telomerase activity. Telomere attrition in oocytes contributes to meiotic dysfunction, including spindle dysmorphologies, reduced synapsis and chiasmata, as well as delayed, arrested and fragmented embryos. Cleavage stage embryos, with such inefficient telomere reconstitution, likely undergo NHEJ, which produces anaphase lag, chromosome bridges, micronuclei, and genomic instability, including mosaicism and CNVs. Cleavage stage embryos reconstitute the short telomeres inherited from their mothers by Alternative Lengthening of Telomeres (ALT), a DNA recombination based method involving RAD 50, MRE 11, Werner and Bloom proteins, as well as telomere sister chromatid exchange. ALT robustly reconstitutes telomeres, but also predisposes to genomic instability.
PMID: 30862510
ISSN: 1878-0849
CID: 3733092
Uterus transplantation in women who are genetically XY
Sampson, Amani; Kimberly, Laura L; Goldman, Kara N; Keefe, David L; Quinn, Gwendolyn P
Uterus transplantation is an emerging technology adding to the arsenal of treatments for infertility; specifically the only available treatment for uterine factor infertility. Ethical investigations concerning risks to uteri donors and transplant recipients have been discussed in the literature. However, missing from the discourse is the potential of uterus transplantation in other groups of genetically XY women who experience uterine factor infertility. There have been philosophical inquiries concerning uterus transplantation in genetically XY women, which includes transgender women and women with complete androgen insufficiency syndrome. We discuss the potential medical steps necessary and associated risks for uterus transplantation in genetically XY women. Presently, the medical technology does not exist to make uterus transplantation a safe and effective option for genetically XY women, however this group should not be summarily excluded from participation in trials. Laboratory research is needed to better understand and reduce medical risk and widen the field to all women who face uterine factor infertility.
PMID: 30803984
ISSN: 1473-4257
CID: 3698282
Assisted reproduction in endometriosis
de Ziegler, Dominique; Pirtea, Paul; Carbonnel, Marie; Poulain, Marine; Cicinelli, Ettore; Bulletti, Carlo; Kostaras, Konstantinos; Kontopoulos, George; Keefe, David; Ayoubi, Jean Marc
Endometriosis - a disease causing pain and infertility - is encountered in nearly 50% of infertile women. While medical treatment is effective on pain and recurrence of symptoms after surgical excision, it is of no help for treating infertility for which the only options considered are surgery and ART. Surgery enhances the chances of conceiving naturally during the 12-18 ensuing months irrespective of the stage of the disease. Surgery however is of no help when ART is considered, as it does not improve outcome and can only harm the ovarian response to stimulation. Today therefore, ART is commonly the primary option to be considered in women whose infertility is associated with endometriosis and whose ovarian reserve is compromised and/or who are over 35 years of age. When, ART is envisioned it is best to opt for a segmented ART approach with agonist trigger, freeze all and deferred embryo transfer.
PMID: 30503728
ISSN: 1878-1594
CID: 3520472
LACTOBACILLUS NON-DOMINANT (LBND) MICROBIOME (MB) IS ASSOCIATED WITH DECREASED VITAMIN D RECEPTOR (VDR) EXPRESSION IN THE ENDOMETRIUM OF WOMEN WHO FAIL EUPLOID FROZEN EMBRYO TRANSFERS (FET). [Meeting Abstract]
Masbou, A. K.; Grifo, J. A.; Wang, F.; Brown, S.; Oh, C.; Hao, Y.; Xia, Y.; Keefe, D. L.
ISI:000448713600216
ISSN: 0015-0282
CID: 3493782
NICKEL EXPOSURE IN VITRO PREVENTS HATCHING IN MOUSE EMBRYOS BY DOWN-REGULATING PLURIPOTENT GENES AND REPRESSING TROPHECTODERM CDX2 EXPRESSION [Meeting Abstract]
Wang, F.; Maxwell, S. M.; Masbou, A. K.; Bourroul, F. M.; Keefe, D. L.
ISI:000448713600429
ISSN: 0015-0282
CID: 3493752
TELOMERE LENGTH AND TELOMERASE ACTIVITY IN REPRODUCTIVE CELLS OF WOMEN WITHPOLYCYSTIC OVARY SYNDROME. [Meeting Abstract]
Pedrosa, D. C.; Miranda-Furtado, C. L.; Picinato, M. C.; Sacilotto Donaires, F.; Giorgenon, R. C.; Santana, V. P.; Santana, B. A.; Pimentel, R. N.; Keefe, D. L.; Calado, R. T.; Ferriani, R. A.; Reis, R. M.
ISI:000448713600287
ISSN: 0015-0282
CID: 3493772
Uroplakins play conserved roles in egg fertilization and acquired additional urothelial functions during mammalian divergence
Liao, Yi; Chang, Hung-Chi; Liang, Feng-Xia; Chung, Pei-Jung; Wei, Yuan; Nguyen, Tuan-Phi; Zhou, Ge; Talebian, Sheeva; Krey, Lewis C; Deng, Fang-Ming; Wong, Tak-Wah; Chicote, Javier U; Grifo, James A; Keefe, David L; Shapiro, Ellen; Lepor, Herbert; Wu, Xue-Ru; DeSalle, Robert; Garcia-España, Antonio; Kim, Sang Yong; Sun, Tung-Tien
Uroplakin (UP) tetraspanins and their associated proteins are major mammalian urothelial differentiation products that form unique 2D-crystals of 16-nm particles ("urothelial plaques") covering the apical urothelial surface. Although uroplakins are highly expressed only in mouse urothelium and are often referred to as being urothelium-specific, they are also expressed in several nonurothelial cell types in stomach, kidney, prostate, epididymis, testis/sperms and ovary/oocytes. In oocytes, uroplakins co-localize with CD9 on cell surface and multivesicular body-derived exosomes, and the cytoplasmic tail of UPIIIa undergoes a conserved fertilization-dependent, Fyn-mediated tyrosine-phosphorylation that also occurs in Xenopus laevis eggs. Uroplakin knockout and antibody blocking reduce mouse eggs' fertilization rate in in vitro fertilization assays, and UPII/IIIa double-knockout mice have a smaller litter size. Phylogenetic analyses showed that uroplakin sequences underwent significant mammal-specific changes. These results suggest that, by mediating signal transduction and modulating membrane stability that do not require 2D-crystal formation, uroplakins can perform conserved and more ancestral fertilization functions in mouse and frog eggs. Uroplakins acquired the ability to form 2D- crystalline plaques during mammalian divergence enabling them to perform additional functions, including umbrella cell enlargement and the formation of permeability and mechanical barriers, in order to protect/modify the apical surface of the modern-day mammalian urothelium.
PMID: 30303751
ISSN: 1939-4586
CID: 3335002
Contemporary Hormonal Contraception and the Risk of Breast Cancer [Comment]
Nachtigall, Lila; Naftolin, Frederick; Keefe, David L
PMID: 29595938
ISSN: 1533-4406
CID: 3025942
Telomere length and early trauma in schizophrenia [Letter]
Riley, Gabriella; Perrin, Mary; Vaez-Azizi, Leila M; Ruby, Eugene; Goetz, Raymond R; Dracxler, Roberta; Walsh-Messinger, Julie; Keefe, David L; Buckley, Peter F; Szeszko, Philip R; Malaspina, Dolores
BACKGROUND:Childhood trauma is emerging as a risk factor for schizophrenia, but its mechanism with respect to etiology is unknown. One possible pathway is through leucocyte telomere length (LTL) shortening, a measure of cellular aging associated with trauma. This study examined early trauma and LTL shortening in schizophrenia and considered sex effects. METHODS:The early trauma inventory (ETI) was administered to 48 adults with DSM-5 schizophrenia and 18 comparison participants. LTL was measured using qPCR. OUTCOMES/RESULTS:Cases had significantly more global trauma (F=4.10, p<0.01) and traumatic events (F=11.23, p<0.001), but case and control groups had similar LTL (1.91±0.74 and 1.83±0.62: p=0.68). The association of early trauma and LTL differed by sex in cases and controls (Fisher's R: Z<0.05). Significant negative associations were shown in male cases and, conversely, in female controls. For example, physical punishment was associated LTL shortening in males' cases (r=-0.429, p<01). Only female controls showed significant telomere shortening in association with early trauma. INTERPRETATION/CONCLUSIONS:This data confirms the substantial excess of early trauma among schizophrenia cases. There were significant sex-differences in the relationship of the trauma to LTL, with only male cases showing the expected shortening. There were converse sex effects in the control group. Mean LTL was notably similar in cases and controls, despite the trauma-related shortening in male cases, cigarette smoking, older age and chronic illness of the cases. Factors may lengthen LTL in some schizophrenia cases. The converse sex differences in the cases are consistent with findings defective sexual differentiation in schizophrenia, consistent with other findings in the field.
PMID: 29618413
ISSN: 1573-2509
CID: 3026082