Eyes open on stem cells.

Recently, the murine cornea has reemerged as a robust stem cell (SC) model, allowing individual SC tracing in living animals. The cornea has pioneered seminal discoveries in SC biology and regenerative medicine, from the first corneal transplantation in 1905 to the identification of limbal SCs and their transplantation to successfully restore vision in the early 1990s. Recent experiments have exposed unexpected properties attributed to SCs and progenitors and revealed flexibility in the differentiation program and a key role for the SC niche. Here, we discuss the limbal SC model and its broader relevance to other tissues, disease, and therapy.

The biophysical property of the limbal niche maintains stemness through YAP.

The cell fate decisions of stem cells (SCs) largely depend on signals from their microenvironment (niche). However, very little is known about how biochemical niche cues control cell behavior in vivo. To address this question, we focused on the corneal epithelial SC model in which the SC niche, known as the limbus, is spatially segregated from the differentiation compartment. We report that the unique biomechanical property of the limbus supports the nuclear localization and function of Yes-associated protein (YAP), a putative mediator of the mechanotransduction pathway. Perturbation of tissue stiffness or YAP activity affects SC function as well as tissue integrity under homeostasis and significantly inhibited the regeneration of the SC population following SC depletion. In vitro experiments revealed that substrates with the rigidity of the corneal differentiation compartment inhibit nuclear YAP localization and induce differentiation, a mechanism that is mediated by the TGFß-SMAD2/3 pathway. Taken together, these results indicate that SC sense biomechanical niche signals and that manipulation of mechano-sensory machinery or its downstream biochemical output may bear fruits in SC expansion for regenerative therapy.

Spotlighting adult stem cells: advances, pitfalls, and challenges.

The existence of stem cells (SCs) at the tip of the cellular differentiation hierarchy has fascinated the scientific community ever since their discovery in the early 1950s to 1960s. Despite the remarkable success of the SC theory and the development of SC-based treatments, fundamental features of SCs remain enigmatic. Recent advances in single-cell lineage tracing, live imaging, and genomic technologies have allowed capture of life histories and transcriptional signatures of individual cells, leaving SCs much less space to 'hide'. Focusing on epithelial SCs and comparing them to other SCs, we discuss new paradigms of the SC niche, dynamics, and pathology, highlighting key open questions in SC biology that need to be resolved for harnessing SC potential in regenerative medicine.

"Going through it together": Being accompanied by loved ones during birth and abortion.

We sought to understand the meaning people who have given birth and have had an abortion ascribe to being accompanied by partners, family members and friends during these reproductive experiences. Incorporating this knowledge into clinical practice may contribute to improving the quality of these services, especially in abortion care, in which loved ones are often excluded. The study took place in Northern California in 2014. We conducted semi-structured, intensive interviews with twenty cis-women about their birth and abortion experiences and analyzed their narratives with respect to accompaniment using grounded theory. The roles of loved ones were complementary yet distinct to those of medical personnel. They were also multifaceted. Participants needed familiar individuals to bear witness, share the emotional experience and provide protection from perceived or possible harm associated with medical care. In some cases, more often in the context of abortion than childbirth, participants shielded their loved ones from emotional burdens of the reproductive process. Some pregnant people of color faced gendered racism, which also influenced their accompaniment needs. Male partners played a distinct role of upholding dominant social ideals related to pregnancy. As is commonplace in birth-related care, abortion services could be formally structured to include partners, family members and friends when desired by pregnant people to improve their experiences. Such integration should be balanced with considerations for privacy, safety and institutional resources. Working toward this goal may reduce structural abortion stigma and help alleviate pregnant people's burdens associated with reproduction.

Discrete limbal epithelial stem cell populations mediate corneal homeostasis and wound healing.

The accessibility and transparency of the cornea permit robust stem cell labeling and in vivo cell fate mapping. Limbal epithelial stem cells (LSCs) that renew the cornea are traditionally viewed as rare, slow-cycling cells that follow deterministic rules dictating their self-renewal or differentiation. Here, we combined single-cell RNA sequencing and advanced quantitative lineage tracing for in-depth analysis of the murine limbal epithelium. These analysis revealed the co-existence of two LSC populations localized in separate and well-defined sub-compartments, termed the "outer" and "inner" limbus. The primitive population of quiescent outer LSCs participates in wound healing and boundary formation, and these cells are regulated by T cells, which serve as a niche. In contrast, the inner peri-corneal limbus hosts active LSCs that maintain corneal epithelial homeostasis. Quantitative analyses suggest that LSC populations are abundant, following stochastic rules and neutral drift dynamics. Together these results demonstrate that discrete LSC populations mediate corneal homeostasis and regeneration.

Effect of a Patient-Centered Decision Support Tool on Rates of Trial of Labor After Previous Cesarean Delivery: The PROCEED Randomized Clinical Trial.

Importance: Reducing cesarean delivery rates in the US is an important public health goal; despite evidence of the safety of vaginal birth after cesarean delivery, most women have scheduled repeat cesarean deliveries. A decision support tool could help increase trial-of-labor rates. Objective: To analyze the effect of a patient-centered decision support tool on rates of trial of labor and vaginal birth after cesarean delivery and decision quality. Design, Setting, and Participants: Multicenter, randomized, parallel-group clinical trial conducted in Boston, Chicago, and the San Francisco Bay area. A total of 1485 English- or Spanish-speaking women with 1 prior cesarean delivery and no contraindication to trial of labor were enrolled between January 2016 and January 2019; follow-up was completed in June 2019. Interventions: Participants were randomized to use a tablet-based decision support tool prior to 25 weeks' gestation (n=742) or to receive usual care (without the tool) (n=743). Main Outcomes and Measures: The primary outcome was trial of labor; vaginal birth was the main secondary outcome. Other secondary outcomes focused on maternal and neonatal outcomes and decision quality. Results: Among 1485 patients (mean age, 34.0 [SD, 4.5] years), 1470 (99.0%) completed the trial (n = 735 in both randomization groups) and were included in the analysis. Trial-of-labor rates did not differ significantly between intervention and control groups (43.3% vs 46.2%, respectively; adjusted absolute risk difference, -2.78% [95% CI, -7.80% to 2.25%]; adjusted relative risk, 0.94 [95% CI, 0.84-1.05]). There were no statistically significant differences in vaginal birth rates (31.8% in both groups; adjusted absolute risk difference, -0.04% [95% CI, -4.80% to 4.71%]; adjusted relative risk, 1.00 [95% CI, 0.86-1.16]) or in any of the other 6 clinical maternal and neonatal secondary outcomes. There also were no significant differences between the intervention and control groups in the 5 decision quality measures (eg, mean decisional conflict scores were 17.2 and 17.5, respectively; adjusted mean difference, -0.38 [95% CI, -1.81 to 1.05]; scores >25 are considered clinically important). Conclusions and Relevance: Among women with 1 previous cesarean delivery, use of a decision support tool compared with usual care did not significantly change the rate of trial of labor. Further research may be needed to assess the efficacy of this tool in other clinical settings or when implemented at other times in pregnancy.

Hospital bans on trial of labor after cesarean and antepartum transfer of care.

BACKGROUND: Hospital policies restricting access to trial of labor after cesarean (TOLAC) are prevalent. Many women with a previous cesarean birth are affected by these bans, but there are limited data on the effect of these bans and whether women would consider changing delivery hospitals in the setting of a real or hypothetical TOLAC ban. METHODS: This was a survey of TOLAC-eligible women receiving prenatal care at four hospitals where TOLAC is available, and 1 non-TOLAC site. Participants were asked about their likelihood of switching hospitals to pursue TOLAC if it were unavailable. Women at the non-TOLAC site had their medical records reviewed to ascertain final location and approach to delivery. RESULTS: A total of 297 women were interviewed, 48 from the non-TOLAC site. 162 (54%) participants indicated they would transfer care if TOLAC were unavailable. Among women at the non-TOLAC site, 57% who indicated an intention to switch hospitals did so. In a multivariable logistic regression model, variables associated with transferring care included race/ethnicity other than Latina (aOR 25.20 [95% CI 2.23-284.26]), being unaware of the TOLAC ban (19.81 [1.99-196.64]), and perceiving that a close friend/relative thought they should undergo TOLAC (17.31 [1.70-176.06]). CONCLUSIONS: More than half of women with prior cesarean would consider transferring care if TOLAC became unavailable, and more than 1 of 3 of women at a non-TOLAC site transferred care. More research is needed on the impact of TOLAC bans and how to facilitate transfer for those who desire TOLAC.

Women's Preferences Regarding the Processes and Outcomes of Trial of Labor After Cesarean and Elective Repeat Cesarean Delivery.

Background: The decrease in trial of labor after cesarean (TOLAC) at institutions that offer this option suggests that patient preference could be a factor in the declining TOLAC rate. However, data regarding how women value the potential processes and outcomes of TOLAC and elective repeat cesarean delivery (ERCD) are limited. We sought to determine how women view the processes and outcomes of TOLAC and ERCD and identify sociodemographic and clinical factors associated with these preferences. Materials and Methods: This is a multicenter cross-sectional study of mode of delivery preferences among TOLAC-eligible women at 26-34 weeks gestation. The time tradeoff metric was used to obtain utilities for the processes and outcomes of TOLAC and ERCD. Multivariable regression analysis was utilized to identify independent predictors of utilities. Results: The 299 study participants constituted a geographically and racially/ethnically diverse group. Although uncomplicated TOLAC resulting in vaginal birth after cesarean and uncomplicated ERCD resulted in high utility values, any alteration in either the process or outcome resulted in substantial utility decrements. In multivariable regression analysis, race/ethnicity, insurance status, and order of scenario presentation emerged as statistically significant predictors. Conclusions: Information regarding both maternal and infant implications is important to women in discussions about approach to delivery. Both the way in which information regarding labor interventions and potential complications is presented and the characteristics of the women contemplating this information affect its impact. These findings underscore the need for evidence-based decision support to help create realistic expectations and incorporate informed patient preferences into decision-making to optimize both clinical outcomes and individual patient experience for women with a prior cesarean delivery.

Induced Abortion Provision Among a National Sample of Obstetrician-Gynecologists.

OBJECTIVE: To estimate the proportion of obstetrician-gynecologists (ob-gyns) who provided induced abortion in the prior year, disaggregated by surgical and medication methods, and document barriers to provision of medication abortion. METHODS: In 2016-2017, we conducted a cross-sectional survey of a national sample of American College of Obstetricians and Gynecologists Fellows and Junior Fellows who were part of the Collaborative Ambulatory Research Network. We sent the survey by email, and mailed nonresponders paper surveys. We performed descriptive statistics, χ tests, and logistic regression analyses. RESULTS: Sixty-seven percent (655/980) of Collaborative Ambulatory Research Network members responded. Ninety-nine percent reported seeing patients of reproductive age, and 72% reported having a patient in the prior year who needed or wanted an abortion. Among those seeing patients of reproductive age, 23.8% (95% CI 20.5%-27.4%) reported performing an induced abortion in the prior year; 10.4% provided surgical and medication abortion, 9.4% surgical only, and 4.0% medication only. In multivariable analysis, physicians practicing in the Midwest (adjusted odds ratio [AOR] 0.31, 95% CI 0.16-0.60) or South (AOR 0.22, 95% CI 0.11-0.42) had lower odds of provision compared with those practicing in the Northeast, whereas those practicing in an urban inner city (AOR 2.71, 95% CI 1.31-5.60) or urban non-inner-city area (AOR 2.89, 95% CI 1.48-5.64 vs midsize towns, rural areas, or military settings) had higher odds of provision. The most common reasons for not providing medication abortion were personal beliefs (34%) and practice restrictions (19%). Among those not providing medication abortion, 28% said they would if they could write a prescription for mifepristone. CONCLUSION: Compared with the previous national survey in 2008-2009, abortion provision may be increasing among practicing ob-gyns, although important geographic disparities persist. Few provide medication abortion, but uptake might increase if mifepristone could be prescribed.

SOX2 Regulates P63 and Stem/Progenitor Cell State in the Corneal Epithelium.

Mutations in key transcription factors SOX2 and P63 were linked with developmental defects and postnatal abnormalities such as corneal opacification, neovascularization, and blindness. The latter phenotypes suggest that SOX2 and P63 may be involved in corneal epithelial regeneration. Although P63 has been shown to be a key regulator of limbal stem cells, the expression pattern and function of SOX2 in the adult cornea remained unclear. Here, we show that SOX2 regulates P63 to control corneal epithelial stem/progenitor cell function. SOX2 and P63 were co-expressed in the stem/progenitor cell compartments of the murine cornea in vivo and in undifferentiated human limbal epithelial stem/progenitor cells in vitro. In line, a new consensus site that allows SOX2-mediated regulation of P63 enhancer was identified while repression of SOX2 reduced P63 expression, suggesting that SOX2 is upstream to P63. Importantly, knockdown of SOX2 significantly attenuated cell proliferation, long-term colony-forming potential of stem/progenitor cells, and induced robust cell differentiation. However, this effect was reverted by forced expression of P63, suggesting that SOX2 acts, at least in part, through P63. Finally, miR-450b was identified as a direct repressor of SOX2 that was required for SOX2/P63 downregulation and cell differentiation. Altogether, we propose that SOX2/P63 pathway is an essential regulator of corneal stem/progenitor cells while mutations in SOX2 or P63 may disrupt epithelial regeneration, leading to loss of corneal transparency and blindness. Stem Cells 2019;37:417-429.

The patient perspective: perceptions of the quality of the abortion experience.

PURPOSE OF REVIEW: Abortion services are essential in sexual and reproductive health and should be held to the same standards as other health services. Patient (or person)-centeredness is a key dimension of healthcare quality that incorporates the perspectives of patients in care provision. The purpose of this review is to summarize studies published in the last year examining women's experiences with abortion care and to describe facilitators and barriers to person-centered care. RECENT FINDINGS: Considering person-centeredness in abortion care using dimensions of dignity, autonomy, privacy, communication, social support, supportive care and health facility environment allows for critical evaluation of data describing women's experiences with abortion and postabortion services. Review of the available literature shed light on the impact of social stigma, health policy and abortion restrictions on women's abortion experiences. SUMMARY: Considering multiple domains and varied settings, current data suggest abortion services worldwide generally fail to provide person-centered care. Institutions and providers may be limited in their ability to provide patient-centered abortion care because of deeply embedded social stigma, institutional regulations and legal restrictions.

RAS Regulates the Transition from Naive to Primed Pluripotent Stem Cells.

The transition from naive to primed state of pluripotent stem cells is hallmarked by epithelial-mesenchymal transition, metabolic switch from oxidative phosphorylation to aerobic glycolysis, and changes in the epigenetic landscape. Since these changes are also seen as putative hallmarks of neoplastic cell transformation, we hypothesized that oncogenic pathways may be involved in this process. We report that the activity of RAS is repressed in the naive state of mouse embryonic stem cells (ESCs) and that all three RAS isoforms are significantly activated upon early differentiation induced by LIF withdrawal, embryoid body formation, or transition to the primed state. Forced expression of active RAS and RAS inhibition have shown that RAS regulates glycolysis, CADHERIN expression, and the expression of repressive epigenetic marks in pluripotent stem cells. Altogether, this study indicates that RAS is located at a key junction of early ESC differentiation controlling key processes in priming of naive cells.

microRNA-184 Induces a Commitment Switch to Epidermal Differentiation.

miR-184 is a highly evolutionary conserved microRNA (miRNA) from fly to human. The importance of miR-184 was underscored by the discovery that point mutations in miR-184 gene led to corneal/lens blinding disease. However, miR-184-related function in vivo remained unclear. Here, we report that the miR-184 knockout mouse model displayed increased p63 expression in line with epidermal hyperplasia, while forced expression of miR-184 by stem/progenitor cells enhanced the Notch pathway and induced epidermal hypoplasia. In line, miR-184 reduced clonogenicity and accelerated differentiation of human epidermal cells. We showed that by directly repressing cytokeratin 15 (K15) and FIH1, miR-184 induces Notch activation and epidermal differentiation. The disease-causing miR-184C57U mutant failed to repress K15 and FIH1 and to induce Notch activation, suggesting a loss-of-function mechanism. Altogether, we propose that, by targeting K15 and FIH1, miR-184 regulates the transition from proliferation to early differentiation, while mis-expression or mutation in miR-184 results in impaired homeostasis.

A good abortion experience: A qualitative exploration of women's needs and preferences in clinical care.

What do women ending their pregnancies want and need to have a good clinical abortion experience? Since birth experiences are better studied, birth stories are more readily shared and many women who have had an abortion have also given birth, we sought to compare women's needs and preferences in abortion to those in birth. We conducted semi-structured intensive interviews with women who had both experiences in the United States and analyzed their intrapartum and abortion care narratives using grounded theory, identifying needs and preferences in abortion that were distinct from birth. Based on interviews with twenty women, three themes emerged: to be affirmed as moral decision-makers, to be able to determine their degree of awareness during the abortion, and to have care provided in a discreet manner to avoid being judged by others for having an abortion. These findings suggest that some women have distinctive emotional needs and preferences during abortion care, likely due to different circumstances and sociopolitical context of abortion. Tailoring services and responding to individual needs may contribute to a good abortion experience.

Male Partners' Involvement in Abortion Care: A Mixed-Methods Systematic Review.

CONTEXT: Although some women may desire the involvement of their partners when obtaining abortion care, male partners are not routinely included in the abortion process. A review of the literature on how male involvement relates to women's abortion experiences may help guide facilities that are considering incorporating male partners in abortion care. METHODS: PubMed, PsycINFO (Ovid), the Cumulative Index to Nursing and Allied Health Literature, the Latin American and Caribbean Health Sciences Literature database, and the Cochrane Library were systematically searched without restrictions through September 23, 2015, to identify qualitative and quantitative primary studies investigating male partner accompaniment during the abortion process in noncoercive situations. Analysis focused on identifying different types of male involvement and their associations with women's abortion experiences. RESULTS: Some 1,316 unique articles were reviewed; 15 were analyzed. These studies were conducted in six countries and published between 1985 and 2012, primarily with observational designs. Four types of male partner involvement emerged: presence in the medical facility, participation in preabortion counseling, presence in the room during the surgical abortion procedure or while the woman is experiencing the effects of abortifacient medications, and participation in postabortion care. Studies explored relationships between type of involvement and women's access to abortion care and their emotional and physical well-being. Most findings suggested that male involvement was positively associated with women's well-being and their assessment of the experience; no negative associations were found. CONCLUSION: In noncoercive circumstances, women who include their male partners in the abortion process may find this involvement beneficial.

A Method for Lineage Tracing of Corneal Cells Using Multi-color Fluorescent Reporter Mice.

Lineage tracing experiments define the origin, fate and behavior of cells in a specific tissue or organism. This technique has been successfully applied for many decades, revealing seminal findings in developmental biology. More recently, it was adopted by stem cell biologists to identify and track different stem cell populations with minimal experimental intervention. The recent developments in mouse genetics, the availability of a large number of mouse strains, and the advancements in fluorescent microscopy allow the straightforward design of powerful lineage tracing systems for various tissues with basic expertise, using commercially available tools. We have recently taken advantage of this powerful methodology to explore the origin and fate of stem cells at the ocular surface using R26R-Confetti mouse. This model offers a multi-color genetic system, for the expression of 4 fluorescent genes in a random manner. Here we describe the principles of this methodology and provide an adaptable protocol for designing lineage tracing experiments; specifically for the corneal epithelium as well as for other tissues.

The WHO's medical eligibility criteria for contraceptive use: 20 years of global guidance.

PURPOSE OF REVIEW: The purpose of this review is to revisit the inception of the WHO's medical eligibility criteria for contraceptive use (MEC), particularly its objectives and methodology, and to describe its impact over the last 20 years in the field of family planning. New recommendations are summarized from the newly released fifth edition of the guidance. RECENT FINDINGS: Fourteen topics, encompassing over 575 recommendations were reviewed for the MEC, fifth edition. New recommendations include: changes for combined hormonal contraceptive use among postpartum women; progestogen-only methods among breastfeeding women; and women at high risk for HIV infection, women living with HIV, and women living with HIV using antiretroviral therapy and hormonal contraception. New methods reviewed include subcutaneously administered depot medroxyprogesterone acetate, Sino-implant (II), ulipristal acetate, and progesterone-releasing vaginal ring. SUMMARY: Over the past 20 years, the MEC has become a remarkably influential document for practitioners and policy makers in family planning, as it provides up-to-date, evidence-based recommendations for contraceptive use for women with various medical conditions and medically relevant characteristics.

Lineage tracing of stem and progenitor cells of the murine corneal epithelium.

Accumulating evidence supports the dogma that the corneal epithelium is regenerated by stem cells located exclusively in the limbal niche, at the corneal periphery. Accordingly, limbal stem cells (LSCs) give rise to progenitors that proliferate and migrate centripetally to repopulate the corneal epithelium, which has a short turnover. Moreover, LSC loss leads to corneal opacity and blindness, while limbal grafting restores patients' vision. However, contradicting data suggested that the limbus does not participate in corneal homeostasis and that the cornea contains stem cells. As of today, only indirect evidence for limbal cell migration under homeostasis or injury has been demonstrated. Here, we performed lineage tracing experiments using R26R-Confetti mice to follow K14+ limbal/corneal epithelial cells stochastically induced to express one out of four fluorescent genes. In homeostasis, radial limbal stripes of slow migrating cells proceeded toward the corneal center while, infrequently, slow cycling limbal clones resembling quiescent stem cells were observed. Additionally, rare corneal clones that did not migrate centripetally, but survived for over 4 months, were inspected. In contrast to limbal stripes, corneal clusters had minor contribution to tissue replenishment in homeostasis. Corneal cells, however, significantly contributed to mild wound repair while large limbal streaks appeared within a week following severe wounding that coincided with partial loss of corneal transparency. This data suggest that the mouse limbus largely contributes to corneal renewal while corneal progenitor cells have a long turnover and, therefore, may be able to maintain the corneal epithelium for several months.

Exploring abortion attitudes of US adolescents and young adults using social media.

OBJECTIVES: To explore the use of social media for recruitment of adolescents and young adults in the United States and to describe how they learn and feel about abortion. STUDY DESIGN: Americans 13-29years of age were recruited through web-based social media to complete an online survey about sex and pregnancy-related decision making, including abortion. Descriptive statistics were used to compare the study population's demographics and prevalence of sexual experience to national databases [US Census and National Survey of Family Growth (NSFG)] and to describe abortion attitudes and related topics. RESULTS: Survey completion rate was 78% and 996 participants' responses were analyzed. The study population appeared diverse with respect to gender, ethnicity, race and geographic distribution with some similarities to the US Census and was sexually active at an earlier age compared to the NSFG. While the majority of participants supported abortion (74%), acceptance of abortion for themselves or their partners varied based on circumstances. The media were the most popular sources of information for learning about sex and abortion (73% and 68%, respectively). Parents had the most influence on individuals' abortion stances compared to other sources. CONCLUSIONS: Social media recruitment, compared to traditional methods, has the potential to reach a geographically, ethnically and racially diverse group of young people to study sensitive topics in an economical and expedient fashion. Similar to the general population, the study population's abortion views fell on a spectrum with overall supportive attitudes toward abortion. The media served as common sources of information for learning about both sex and abortion. IMPLICATIONS: Web-based social media offer a novel recruiting strategy to study sensitive topics such as abortion attitudes among difficult-to-reach populations such as adolescents and young adults. The presented findings begin characterizing young people's abortion attitudes, offering a foundation for more in-depth research.