C.R. Sacha

Eulemur, me lemur: the evolution of scent-signal complexity in a primate clade

Signal complexity has been linked to social complexity in vocal, but not chemical, communication. To address this gap, we examined the chemical complexity of male and female glandular secretions in eight species of Eulemur. In this diverse clade of macrosmatic primates, species differ by social or mating system and dominance structure. We applied principal component and linear discriminate analyses to data obtained by gas chromatography/mass spectrometry. Beyond the significant effects on chemical signals of gland type, sex, season and species, we found effects of social variables and phylogeny. Notably, female odours were more chemically complex in multimale–multifemale species than pair-bonded species, whereas male odours were more chemically complex in codominant species than female-dominant species. Also, the traditional sexual dimorphism, whereby male signal complexity exceeds that of females, was present in codominant species, but reversed in female-dominant species. Lastly, a positive relationship between the species pairwise chemical distances and their pairwise phylogenetic distances supported a gradual, but relatively fast mode of signal evolution. We suggest that the comparative method can be a powerful tool in olfactory research, revealing species differences relevant to the understanding of current signal utility and evolutionary processes. In particular, social complexity in lemurs may have selected for olfactory complexity.

The "secret" in secretions: methodological considerations in deciphering primate olfactory communication.

Olfactory communication in primates is gaining recognition; however, studies on the production and perception of primate scent signals are still scant. In general, there are five tasks to be accomplished when deciphering the chemical signals contained in excretions and secretions: (1) obtaining the appropriate samples; (2) extracting the target organic compounds from the biological matrix; (3) separating the extracted compounds from one another (by gas chromatography, GC or liquid chromatography, LC); (4) identifying the compounds (by mass spectrometry, MS and associated procedures); and (5) revealing biologically meaningful patterns in the data. Ultimately, because some of the compounds identified in odorants may not be relevant, associated steps in understanding signal function involve verifying the perception or biological activity of putative semiochemicals via (6) behavioral bioassays or (7) receptor response studies. This review will focus on the chemical analyses and behavioral bioassays of volatile, primate scent signals. Throughout, we highlight the potential pitfalls of working with highly complex, chemical matrices and suggest ways for minimizing problems. A recurring theme in this review is that multiple approaches and instrumentation are required to characterize the full range of information contained in the complex mixtures that typify primate or, indeed, many vertebrate olfactory cues. Only by integrating studies of signal production with those verifying signal perception will we better understand the function of olfactory communication. Am. J. Primatol. 75:621–642, 2013.

The effect of short-term exposure of cumulus-oocyte complexes to in vitro maturation medium on yield of mature oocytes and usable embryos in stimulated cycles

PurposeWe examined whether short-term exposure to in vitro maturation (IVM) medium of cumulus-oocyte complexes (COCs) from a stimulated cycle increases the yield of metaphase II (MII) oocytes and usable embryos.MethodsRetrospective review of two consecutive autologous IVF/ICSI cycles per patient between 2007 and 2015 in which cycle 1 did not result in live birth. Patients with short-term exposure of COCs to IVM medium (3–5xa0h before standard insemination or ICSI) in cycle 2 (treated) were matched 1:4 on %MI and %MII to patients without use of IVM in cycle 2 (untreated). The proportions of mature oocytes, two pronucleate (2PN) zygotes, number of usable embryos, and clinical outcomes were compared between groups with regression modeling.ResultsThe treated (nu2009=u200943) and untreated (nu2009=u2009163) groups had similar demographic characteristics and similarly high proportions of immature oocytes (48.2 vs. 41.3%, respectively) in cycle 1. There were no significant differences between the treated and untreated groups in the change in %MII (48.1 to 68.9% vs. 50.5 to 72.5%, respectively) or mean number of usable embryos (2.2 to 3.4 vs. 2.0 to 3.3, respectively) from cycle 1 to cycle 2.ConclusionsThese findings suggest that short-term IVM incubation of COCs may not provide any additional benefit in patients with a prior unsuccessful cycle notable for a high proportion of immature oocytes. Further randomized studies are warranted to determine whether there is a subset of patients who may have improved clinical outcomes with this “rescue IVM” intervention.

The effect of day 2 versus day 3 embryo transfer on early pregnancy outcomes in women with a low yield of fertilized oocytes

PurposeTo evaluate the differences in implantation and pregnancy rates when embryo transfer occurs on D2 versus D3 in women with a low yield of fertilized oocytes.MethodsA total of 156 IVF/ICSI cycles from 141 women at an academic fertility center were analyzed in a retrospective fashion. Women with a low number of fertilized oocytes (≤u20092 two pronuclei (2PN) stage zygotes) who had their fresh embryo transfer on D2 or D3 were included in the study. Positive pregnancy test per IVF cycle (PPT), clinical pregnancy rate (CPR), spontaneous abortion rate (SABR), and implantation rate (IMPR) were the main outcome measures assessed. Mann-Whitney U test and χ2 test were used as appropriate. A generalized linear mixed effect model adjusted for relevant covariates was conducted. Pu2009<u20090.05 was considered significant.ResultsPatients having their embryo transfer on D2, when compared to those who had a D3 embryo transfer, experienced similar PPT [30.8 vs. 28.2%, respectively; adjusted OR (95%CI): 0.49 (0.16, 1.52)], CPR [26.9 vs. 25.6%, respectively; adjusted OR (95%CI): 0.44 (0.12, 1.67)], and IMPR [17.3 vs. 16.7%, respectively; adjusted β (95%CI) −u20095.6% (−u200915.0, 3.9)].ConclusionOur findings suggest that transferring embryos on D2 versus D3 in women with a limited number of 2PN stage zygotes does not affect early pregnancy outcomes. These results indicate that there can be some flexibility in scheduling the day of transfer at the convenience of both the patient and the center.

Differentiating mouse embryonic stem cells express markers of human endometrium

BackgroundModeling early endometrial differentiation is a crucial step towards understanding the divergent pathways between normal and ectopic endometrial development as seen in endometriosis.MethodsTo investigate these pathways, mouse embryonic stem cells (mESCs) and embryoid bodies (EBs) were differentiated in standard EB medium (EBM). Immunofluorescence (IF) staining and reverse-transcription polymerase chain reaction (RT-PCR) were used to detect expression of human endometrial cell markers on differentiating cells, which were sorted into distinct populations using fluorescence-activated cell sorting (FACS).ResultsA subpopulation (50%) of early differentiating mESCs expressed both glandular (CD9) and stromal (CD13) markers of human endometrium, suggestive of a novel endometrial precursor cell population. We further isolated a small population of endometrial mesenchymal stem cells, CD45−/CD146+/PDGFR-β+, from differentiating EBs, representing 0.7% of total cells. Finally, quantitative PCR demonstrated significantly amplified expression of transcription factors Hoxa10 and Foxa2 in CD13+ EBs isolated by FACS (pxa0=xa00.03).ConclusionsThese findings demonstrate that mESCs have the capacity to express human endometrial cell markers and demonstrate potential differentiation pathways of endometrial precursor and mesenchymal stem cells, providing an in vitro system to model early endometrial tissue development. This model represents a key step in elucidating the mechanisms of ectopic endometrial tissue growth. Such a system could enable the development of strategies to prevent endometriosis and identify approaches for non-invasive monitoring of disease progression.

Are women with obesity and infertility willing to attempt weight loss prior to fertility treatment

OBJECTIVEnTo assess attitudes towards weight loss interventions in patients seeking infertility treatment.nnnMETHODSnWe evaluated prior weight loss experiences, attitudes towards future interventions by body mass index (BMI), and willingness to delay fertility treatment for weight loss interventions stratified by BMI using logistic regression amongst women ≤45years old with infertility over three months or recurrent pregnancy loss.nnnRESULTSnThe average age of our convenience sample of respondents (148 of 794 eligible women, 19%) was 34.5 years old, with a mean BMI of 26.7±7.4kg/m2, including 37 with a BMI >30kg/m2 (25%). Most women had attempted conception over 1year. The majority of women with overweight or obesity were attempting weight loss at the time of survey completion (69%). While 47% of these women reported interest in a supervised medical weight loss program, 92% of overweight women and 84% of women with obesity were not willing to delay fertility treatment more than 3 months to attempt weight loss.nnnCONCLUSIONnMost women with obesity and infertility in our population are unwilling to postpone fertility treatment for weight loss interventions.

Abnormal Uterine Bleeding in Women with Infertility

Purpose of ReviewAbnormal uterine bleeding (AUB) is a common gynecologic complaint of reproductive-age women that necessitates careful evaluation due to potential underlying structural and systemic abnormalities. The majority of studies on AUB and infertility examine these topics separately, despite emerging evidence that many etiologies of AUB influence fertility. This review aims to provide an updated perspective on the diagnosis and management of AUB in the context of the infertility evaluation.Recent FindingsThe FIGO PALM-COEIN classification of AUB allows for the precise identification of systemic and structural causes to guide management. Pelvic ultrasound continues to be an accessible first-line imaging technique with high sensitivity for detecting structural etiologies of abnormal bleeding, particularly when used with color Doppler or 3D imaging. Notably, recent studies suggest that many of the endometrial pathologies that lead to AUB can also negatively impact endometrial receptivity, perhaps contributing to infertility in some women.SummaryWhile the impact of systemic causes of AUB, such as ovulatory dysfunction, on infertility is widely recognized, the extents to which endometrial disorders and discrete structural lesions affect fertility are not entirely understood. More research is needed to assess the impact of structural abnormalities and their treatment on subsequent fertility outcomes in women with AUB.