Gary A. Dildy, MD Haleh Sangi-Haghpeykar, PhD Department of Obstetrics and Gynecology Baylor College of Medicine Houston, TX The authors report no conflict of interest. REFERENCES 1. Moaddab A, Dildy GA, Brown HL, et al. Health care disparity and state-specific pregnancy-related mortality in the United States, 2005-2014. Obstet Gynecol 2016;128:869-75. 2. Huckman RS, Barro JR. Cohort turnover and productivity: the July phenomenon in teaching hospitals. NBER working paper no. 11182. Inaugural conference of the American Society of Health Economists. March 2005; Cambridge, MA. JEL no. I1, J0: 1-42. Available at: http:// www.nber.org/papers/w11182.pdf. Accessed June 29, 2017. 3. Myles TD. Is there an obstetric July phenomenon? Obstet Gynecol 2003;102:1080-4. 4. Caughey AB. The July phenomenon: why don’t we see it in obstet- rics? J Perinatol 2007;27:71-2. 5. Ayanian JZ, Weissman JS. Teaching hospitals and quality of care: a review of the literature. Milbank Q 2002;80:569-93. ª 2017 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.ajog. 2017.05.063 Bacterial endotoxin exposure invokes transcriptional changes in embryonic murine neural stem cells FIGURE LPS alters the expression and potential of murine neural stem A-B, NE-GFP-4C murine neural stem cells were treated with 100 nanograms per ml of LPS or the vehicle control (PBS) and collected for gene expression analysis and visualization of ubiquitously expressed cytoplasmic green fluorescent protein (GFP), 24 hours postexposure. C-D, NE-GFP- 4C cells were exposed to LPS or control for 24 hours, then washed and treated with 1 micromolar retinoic acid (RA) for 48 hours to induce neural differentiation. Cells were collected for gene expression analysis and stained for beta-III Tubulin with Alex Fluor 555, 14 days post-RA exposure. Gene expression represents the mean of N ¼ 3 replicates for each experimental condition analyzed by quantitative reverse transcription-PCR and DCt methods. P values were calculated by student’s t-test and error bars represent the standard error of the mean. For visualization, cells were first fixed with 4% formaldehyde for 20 minutes and then stained and/or directly images by epifluorescence microscopy. Scale bars ¼ 100 micrometers. Estrada et al. Bacterial endotoxin exposure invokes transcriptional changes in embryonic murine neural stem cells. Am J Obstet Gynecol 2017. 488 American Journal of Obstetrics & Gynecology OCTOBER 2017 Research Letters ajog.org