Spatial transcriptomics of fetal membrane-Decidual interface reveals unique contributions by cell types in term and preterm births.

During pregnancy, two fetomaternal interfaces, the placenta-decidua basalis and the fetal membrane-decidua parietals, allow for fetal growth and maturation and fetal-maternal crosstalk, and protect the fetus from infectious and inflammatory signaling that could lead to adverse pregnancy outcomes. While the placenta has been studied extensively, the fetal membranes have been understudied, even though they play critical roles in pregnancy maintenance and the initiation of term or preterm parturition. Fetal membrane dysfunction has been associated with spontaneous preterm birth (PTB, < 37 weeks gestation) and preterm prelabor rupture of the membranes (PPROM), which is a disease of the fetal membranes. However, it is unknown how the individual layers of the fetal membrane decidual interface (the amnion epithelium [AEC], the amnion mesenchyme [AMC], the chorion [CTC], and the decidua [DEC]) contribute to these pregnancy outcomes. In this study, we used a single-cell transcriptomics approach to unravel the transcriptomics network at spatial levels to discern the contributions of each layer of the fetal membranes and the adjoining maternal decidua during the following conditions: scheduled caesarian section (term not in labor [TNIL]; n = 4), vaginal term in labor (TIL; n = 3), preterm labor with and without rupture of membranes (PPROM; n = 3; and PTB; n = 3). The data included 18,815 genes from 13 patients (including TIL, PTB, PPROM, and TNIL) expressed across the four layers. After quality control, there were 11,921 genes and 44 samples. The data were processed by two pipelines: one by hierarchical clustering the combined cases and the other to evaluate heterogeneity within the cases. Our visual analytical approach revealed spatially recognized differentially expressed genes that aligned with four gene clusters. Cluster 1 genes were present predominantly in DECs and Cluster 3 centered around CTC genes in all labor phenotypes. Cluster 2 genes were predominantly found in AECs in PPROM and PTB, while Cluster 4 contained AMC and CTC genes identified in term labor cases. We identified the top 10 differentially expressed genes and their connected pathways (kinase activation, NF-κB, inflammation, cytoskeletal remodeling, and hormone regulation) per cluster in each tissue layer. An in-depth understanding of the involvement of each system and cell layer may help provide targeted and tailored interventions to reduce the risk of PTB.

PGRMC2 and HLA-G regulate immune homeostasis in a microphysiological model of human maternal-fetal membrane interface.

Chorion trophoblasts (CTCs) and immune cell-enriched decidua (DECs) comprise the maternal-fetal membrane interface called the chorio-decidual interface (CDi) which constantly gets exposed to maternal stressors without leading to labor activation. This study explored how CTCs act as a barrier at CDi. The roles of human leukocyte antigen (HLA)-G and progesterone receptor membrane component 2 (PGRMC2) in mediating immune homeostasis were also investigated. The CDi was recreated in a two-chamber microfluidic device (CDi-on-chip) with an outer chamber of primary DECs and immune cell line-derived innate immune cells and an inner chamber of wild-type or PGRMC2 or HLA-G knockout immortalized CTCs. To mimic maternal insults, DECs were treated with lipopolysaccharide, poly(I:C), or oxidative stress inducer cigarette smoke extract. Expression levels of inflammation and immunity genes via targeted RNA sequencing, production of soluble mediators, and immune cell migration into CTCs were determined. In CDi-on-chip, decidua and immune cells became inflammatory in response to insults while CTCs were refractory, highlighting their barrier function. HLA-G and PGRMC2 are found to be vital to immune homeostasis at the CDi, with PGRMC2 serving as an upstream regulator of inflammation, HLA-G expression, and mesenchymal-epithelial transition, and HLA-G serving as a frontline immunomodulatory molecule, thus preventing fetal membrane compromise.

Psychosocial Assessment Tool 2.0 and Long-Term Mental Health Outcomes in Childhood Cancer.

To identify childhood cancer patients and their families at the greatest risk for psychosocial difficulties, this study examined the predictive validity of the Psychosocial Assessment Tool 2.0 (PAT2.0) on caregiver and patient-reported mental health outcomes at 1-year follow-up. The PAT2.0 was administered to caregivers a median of 0.08 years after cancer diagnosis. A brief psychosocial screening battery (Family Symptom Inventory and PROMIS v1.0 Pediatric Profile-25) was administered to patient-caregiver dyads (n=53) ∼1-year later. Linear regressions support the longitudinal predictive validity of the PAT2.0 for caregiver-reported child and caregiver mental health symptoms and child-reported peer relationships difficulties.

Perioperative Gastrointestinal Myoelectric Activity Measurement Using Wireless External Patches.

BACKGROUND: Stomach, small intestine, and colon have distinct patterns of contraction related to their function to mix and propel enteric contents. In this study, we aim to measure gut myoelectric activity in the perioperative course using external patches in an animal model. METHODS: Four external patches were placed on the abdominal skin of female Yucatan pigs to record gastrointestinal myoelectric signals for 3 to 5 d. Pigs subsequently underwent anesthesia and placement of internal electrodes on stomach, small intestine, and colon. Signals were collected by a wireless transmitter. Frequencies associated with peristalsis were analyzed for both systems for 6 d postoperatively. RESULTS: In awake pigs, we found frequency peaks in several ranges, from 4 to 6.5 cycles per minute (CPM), 8 to 11 CPM, and 14 to 18 CPM, which were comparable between subjects and concordant between internal and external recordings. The possible effect of anesthesia during the 1 or 2 h before surgical manipulation was observed as a 59% (±36%) decrease in overall myoelectric activity compared to the immediate time before anesthesia. The myoelectrical activity recovered quickly postoperatively. Comparing the absolute postsurgery activity levels to the baseline for each pig revealed higher overall activity after surgery by a factor of 1.69 ± 0.3. CONCLUSIONS: External patch measurements correlated with internal electrode recordings. Anesthesia and surgery impacted gastrointestinal myoelectric activity. Recordings demonstrated a rebound phenomenon in myoelectric activity in the postoperative period. The ability to monitor gastrointestinal tract myoelectric activity noninvasively over multiple days could be a useful tool in diagnosing gastrointestinal motility disorders.

Capturing the complexity of child behavior and caregiver-child interactions in the HEALthy Brain and Child Development (HBCD) Study using a rigorous and equitable approach.

The HEALthy Brain and Child Development (HBCD) Study, a multi-site prospective longitudinal cohort study, will examine human brain, cognitive, behavioral, social, and emotional development beginning prenatally and planned through early childhood. This article outlines methodological considerations and the decision-making process for measurement selection for child behavior, parenting/caregiver-child interactions, and the family/home environment for HBCD. The decision-making process is detailed, including formation of a national workgroup (WG-BEH) that focused on developmentally appropriate measures that take a rigorous and equitable approach and aligned with HBCD objectives. Multi-level-observational and caregiver-report measures were deemed necessary for capturing the desired constructs across multiple contexts while balancing the nuance of observational data with pragmatic considerations. WG-BEH prioritized developmentally sensitive, validated assessments with psychometrics supporting use in diverse populations and focused on mechanistic linkages and prediction of desired constructs. Other considerations included participant burden and retention, staff training needs, and cultural sensitivity. Innovation was permitted when it was grounded in evidence and filled key gaps. Finally, this article describes the rationale for the selected constructs (e.g., temperament, social-emotional development, parenting behaviors, family organization) and corresponding measures chosen for HBCD visits from early infancy through 17 months of age.

Diversity, Equity, and Inclusion in US Anesthesiology Residency Matching.

BACKGROUND: Patient outcomes are improved with physician-patient gender, racial, and ethnic concordance. However, female, Black, Hispanic or Latino, Native Hawaiian-Pacific Islander (NH-PI), and American Indian-Native Alaskan (AI-AN) physicians are underrepresented in anesthesiology. The American Association of Medical Colleges 2018 Diversity in Medicine Report revealed that women comprise only 35% of anesthesiologists yet nearly half of medical school graduates are women. More than 77% of anesthesiologists are White or Asian. Anesthesiology applicant and match trends may provide insights needed to address underrepresentation within anesthesiology. We hypothesized that proportionally fewer women and racially and ethnically minoritized applicants apply and match into anesthesiology. METHODS: This retrospective observational study identified 47,117 anesthesiology applicants among the 546,298 residency applicants in the Electronic Residency Application Service (ERAS) system between 2011 and 2022 and stratified applicants by self-reported gender, race, and ethnicity. The demographics of anesthesiology trainees reported in the 2014 to 2015, 2018 to 2019, and 2022 to 2023 Accreditation Counsel of Graduate Medical Education (ACGME) Data Resource Books were used as surrogates for matched applicants as demographics are not reported by the National Residency Match Program. To facilitate comparisons, ERAS applicants were grouped into 4-year epochs to align with consolidated ACGME reports corresponding to the application years. Odds ratios (OR); 95% confidence interval of applying to and matching into anesthesiology were analyzed. RESULTS: Women had lower odds of applying to anesthesiology compared to men overall (OR, 0.55; 95% CI, 0.54-0.56, P < .0001) and maintained significantly lowered odds of applying within each epoch. Women had similar odds of matching into anesthesiology residency compared to men (OR, 1.10; 95% CI, 1.06-1.14, P < .0001). Black, Hispanic or Latino, Asian and NH-PI, and AI-AN applicants had similar odds to White applicants of applying to anesthesiology but odds of matching were significantly lower overall (P < .0001) for Asian and NH-PI (OR, 0.66; 95% CI, 0.63-0.70), Black (OR, 0.49; 95% CI, 0.45-0.53), Hispanic or Latino (OR, 0.50; 95% CI, 0.46-0.54), and AI-AN (OR, 0.20; 95% CI, 0.15-0.28) applicants. The odds of matching among some minoritized applicants increased in the ACGME 2022 to 2023 report year. CONCLUSIONS: From 2011 to 2022, women had lower odds of applying to anesthesiology residency than men yet had similar odds of matching. Racial and ethnic minoritized groups had significantly lower odds of matching compared to White applicants despite similar odds of applying. These findings highlight disparities in the anesthesiology match and may help identify opportunities to promote workforce diversity within the field. More detailed reporting of gender, race, and ethnicity in annual match data may better define barriers to entry and identify opportunities for improvement.

Microbial, holobiont, and Tree of Life eDNA/eRNA for enhanced ecological assessment.

Microbial environmental DNA and RNA (collectively 'eNA') originate from a diverse and abundant array of microbes present in environmental samples. These eNA signals, largely representing whole organisms, serve as a powerful complement to signals derived from fragments or remnants of larger organisms. Integrating microbial data into the toolbox of ecosystem assessments and biotic indices therefore has the potential to transform how we use eNA data to understand biodiversity dynamics and ecosystem functions, and to inform the next generation of environmental monitoring. Incorporating holobiont and Tree of Life approaches into eNA analyses offers further holistic insight into the range of ecological interactions between microbes and other organisms, paving the way for advancing our understanding of, and ultimately manipulating ecosystem properties pertinent to environmental management, conservation, wildlife health, and food production.

The consequences of AI training on human decision-making.

AI is now an integral part of everyday decision-making, assisting us in both routine and high-stakes choices. These AI models often learn from human behavior, assuming this training data is unbiased. However, we report five studies that show that people change their behavior to instill desired routines into AI, indicating this assumption is invalid. To show this behavioral shift, we recruited participants to play the ultimatum game, where they were asked to decide whether to accept proposals of monetary splits made by either other human participants or AI. Some participants were informed their choices would be used to train an AI proposer, while others did not receive this information. Across five experiments, we found that people modified their behavior to train AI to make fair proposals, regardless of whether they could directly benefit from the AI training. After completing this task once, participants were invited to complete this task again but were told their responses would not be used for AI training. People who had previously trained AI persisted with this behavioral shift, indicating that the new behavioral routine had become habitual. This work demonstrates that using human behavior as training data has more consequences than previously thought since it can engender AI to perpetuate human biases and cause people to form habits that deviate from how they would normally act. Therefore, this work underscores a problem for AI algorithms that aim to learn unbiased representations of human preferences.

External Validation of the Recalibrated HEART Score for Evaluation of Possible Acute Coronary Syndrome.

A single high-sensitivity troponin-T (hs-TnT) measurement may be sufficient to risk-stratify emergency department (ED) patients with possible acute coronary syndrome (ACS) using the recalibrated History, Electrocardiogram, Age, Risk Factors, Troponin (rHEART) score. We sought to validate this approach in a multiethnic population of United States patients and investigate gender-specific differences in performance. We conducted a secondary analysis of a prospective cohort study of adult ED patients with possible ACS at a single, urban, academic hospital. We investigated the diagnostic performance of rHEART for the incidence of type-1 acute myocardial infarction (AMI) and other major adverse cardiac events (MACE) at 30 days, using both single (19 ng/L) and gender-specific (14 ng/L for women, 22 ng/L for men) 99th percentile hs-TnT thresholds. The 821 patients included were 54% women, 57% Hispanic, and 26% Black. Overall, 4.6% of patients had MACE, including 2.4% with AMI. Single-threshold rHEART ≤3 had a sensitivity of 94.4% (95% confidence interval 81% to 99%) and negative predictive values of 99.3% (98% to 100%) for MACE; gender-specific thresholds performed nearly identically. Sensitivity and negative predictive values for AMI were 90.0% (67% to 98%) and 99.3% (97% to 100%). Excluding patients presenting <3 hours from symptom onset improved sensitivity for MACE and AMI to 97.0% (84% to 100%) and 94.1% (71% to 100%). Logistic regression demonstrated odds of MACE increased with higher rHEART scores at a similar rate for men and women. In conclusion, a single initial hs-TnT and rHEART score can be used to risk-stratify male and female ED patients with possible ACS, especially when drawn >3 hours after symptom onset.

Postinjury Pneumonia Induces a Unique Blood Microbiome Signature.

BACKGROUND: Previous preclinical studies have demonstrated a pathobiome after traumatic injury; however, the impact of post-injury sepsis on gut epithelial permeability and bacterial translocation remains unknown. We hypothesized that polytrauma with post-injury pneumonia would result in impaired gut permeability leading to specific blood microbiome arrays. METHODS: Male and proestrus female Sprague-Dawley rats were subjected to either polytrauma (PT), PT plus 2-hours daily chronic restraint stress (PT/CS), PT with postinjury day 1 inoculation with pseudomonas pneumonia (PT + PNA), PT/CS + PNA, or naive controls. Whole blood microbiome was measured serially using high-throughput 16S rRNA sequencing and QIIME2 bioinformatics analyses. Microbial diversity was assessed using Chao1/Shannon indices and principle coordinate analysis. Intestinal permeability was evaluated by plasma occludin and lipopolysaccharide-binding protein (LBP) assays. RESULTS: PT/CS + PNA had increased intestinal permeability compared to uninfected counterparts (PT/CS) with significantly elevated occludin (p < 0.01). Bacteria was not detected in the blood of naïve controls, PT or PT/CS, but was present in both PT + PNA and PT/CS + PNA on days two and seven. The PT/CS + PNA blood biome showed dominance of Streptococcus compared to PT + PNA at day two (p < 0.05). Females PT/CS + PNA had a significant abundance of Staphylococcus at day two and Streptococcus at day seven in the blood biome compared to male counterparts (p < 0.05). CONCLUSIONS: Multicompartmental trauma with post-injury pneumonia results in increased intestinal permeability and bacteremia with a unique blood biome, with sexual dimorphisms evident in the blood biome composition. These findings suggest that post-injury sepsis has clinical significance and could influence outcomes after severe trauma and critical illness.

Combined interpretation of objective firearm evidence comparison algorithms using Bayesian networks.

Traditionally, firearm and toolmark examiners manually evaluate the similarity of features on two bullets using comparison microscopy. Advances in microscopy have made it possible to collect 3D topographic data, and several automated comparison algorithms have been introduced for the comparison of bullet striae using these data. In this study, open-source approaches for cross-correlation, congruent matching profile segments, consecutive matching striations, and a random forest model were evaluated. A statistical characterization of these automated approaches was performed using four datasets of consecutively manufactured firearms to provide a challenging comparison scenario. Each automated approach was applied to all samples in a pairwise fashion, and classification performance was compared. Based on these findings, a Bayesian network was empirically learned and constructed to leverage the strengths of each individual approach, model the relationship between the automated results, and combine them into a posterior probability for the given comparison. The network was evaluated similarly to the automated approaches, and the results were compared. The developed Bayesian network classified 99.6% of the samples correctly, and the resultant probability distributions were significantly separated more so than the automated approaches when used in isolation.

C-reactive protein across pregnancy in individuals exposed to childhood maltreatment: The role of psychological and physical sequelae of maltreatment.

BACKGROUND: Childhood maltreatment (CM) has long-term consequences for the regulation of stress biology which are particularly pronounced when mental and physical health sequelae have manifested. C-reactive protein (CRP) has been shown to be elevated in the non-pregnant state in association with CM as well as in the setting of CM-associated mental and physical health sequelae. In pregnancy, however, the association between CM and CRP is less clear. We sought to examine this association and consider the moderating role of four common health sequelae of CM (maternal depressive symptoms, overweight/obesity, smoking, and hypertensive disorders during pregnancy). METHODS: A prospective, longitudinal study of 744 healthy pregnant participants was conducted, with analyses focusing on a sample of 643 participants. CM was assessed with the Childhood Trauma Questionnaire (CTQ) and categorized by whether no vs. one or more moderate to severe CM experiences were reported. Blood serum concentrations of CRP, maternal depression severity (continuous scores of the Center for Epidemiologic Studies Depression Scale, CES-D) and smoking during pregnancy were assessed in early (16.52 ± 2.50 weeks gestation) and late (33.65 ± 1.18 weeks gestation) pregnancy. Pre-pregnancy body mass index (BMI) was obtained at the first study visit and hypertensive disorders diagnosed during pregnancy were obtained from the medical record. Linear mixed effects models were employed to assess main effects of CM as well as interactive effects of CM and four common CM-associated sequelae as well as a sum score of these sequelae on repeatedly measured CRP concentration. In secondary analyses, we conducted latent class analyses to classify participants based on their specific experiences of childhood abuse and/or neglect and to assess the association of these CM subgroups with CM sequelae and CRP. All analyses were adjusted for potential confounders (maternal race and ethnicity and education/income). RESULTS: CRP concentration decreased from early to late pregnancy (B = -0.06, SE = 0.01, p < 0.001). While there was no main effect of CM on CRP (p = 0.49), the interaction of CM and depressive symptoms was associated with CRP concentration (B = 0.08, SE = 0.04, p < 0.05), indicating higher CRP across pregnancy with increasing levels of depressive symptoms during pregnancy in participants with CM experience. This interaction was mainly driven by participants with co-occurring physical and emotional maltreatment. For none of the other CM-associated sequelae a statistically significant interaction with CM on CRP concentration was observed. CONCLUSIONS: These results add to the growing empirical evidence suggesting higher inflammation during pregnancy in participants exposed to CM who experience depressive symptoms and highlight the detrimental effects of multiple co-occurring experiences of maltreatment. Given the negative consequences of chronic inflammatory state for the mother and the developing fetus, monitoring and treating psychiatric sequelae during pregnancy among participants exposed to CM is potentially an important opportunity to dampen long-term detrimental effects of CM, serving at least two generations.

Endoscopic techniques for management of large colorectal polyps, strictures and leaks.

The implementation of screening colonoscopy with polyp removal has significantly decreased mortality rates associated with colorectal cancer (CRC), although it remains a major cause of cancer-related deaths globally. CRC typically originates from adenomatous polyps, and increased removal of these growths has led to reduced CRC incidence and mortality. Endoscopic polypectomy techniques, including hot and cold snare polypectomy, play a pivotal role in this process. While both methods are effective for small polyps (<10 mm), recent evidence favors cold snare polypectomy due to its superior safety profile and comparable complete resection rates. Large polyps (>10 mm), particularly those with advanced features, pose increased cancer risks and often require meticulous assessment and advanced endoscopic techniques, including endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD), for resection. This chapter also provides a practical overview of endoscopic techniques for managing colonic obstructions and pericolonic fluid collections, detailing their indications, advantages, disadvantages, and complications. The goal is to improve understanding and application in clinical practice. Additionally, we provide a summary of endoscopic closure techniques that have revolutionized the management of perforations and fistulas, offering safe and effective alternatives to surgery.

Intolerance of uncertainty as a predictor of anxiety severity and trajectory during the COVID-19 pandemic.

BACKGROUND: Efforts to identify risk and resilience factors for anxiety severity and course during the COVID-19 pandemic have focused primarily on demographic rather than psychological variables. Intolerance of uncertainty (IU), a transdiagnostic risk factor for anxiety, may be a particularly relevant vulnerability factor. METHOD: N = 641 adults with pre-pandemic anxiety data reported their anxiety, IU, and other pandemic and mental health-related variables at least once and up to four times during the COVID-19 pandemic, with assessments beginning in May 2020 through March 2021. RESULTS: In preregistered analyses using latent growth models, higher IU at the first pandemic timepoint predicted more severe anxiety, but also a sharper decline in anxiety, across timepoints. This finding was robust to the addition of pre-pandemic anxiety and demographic predictors as covariates (in the full sample) as well as pre-pandemic depression severity (in participants for whom pre-pandemic depression data were available). Younger age, lower self/parent education, and self-reported history of COVID-19 illness at the first pandemic timepoint predicted more severe anxiety across timepoints with strong model fit, but did not predict anxiety trajectory. CONCLUSIONS: IU prospectively predicted more severe anxiety but a sharper decrease in anxiety over time during the pandemic, including after adjustment for covariates. IU therefore appears to have unique and specific predictive utility with respect to anxiety in the context of the COVID-19 pandemic.

Skin fibrosis is accompanied by increased expression of secreted frizzled-related protein-2.

Dermal fibrosis is a consequence of damage to skin and is accompanied by dysfunction and cosmetic disfigurement. Improved understanding of the pathological factors driving skin fibrosis is critical to development of therapeutic modalities. Here, we describe that the Wnt signalling antagonist SFRP2 is upregulated in organotypic keratinocyte cultures upon experimental reduced hydration, a model that simulates the aberrant epidermal barrier state characteristic of several skin pathologies, including those that manifest in development of fibrosis. Consistent with this, we find that SFRP2 is overexpressed in both the dermis and epidermis of human hypertrophic scar tissue and lesional tissue of a mouse scleroderma model. Knockdown of SFRP2 expression in human fibroblasts antagonises proliferation and myofibroblast differentiation, including deposition of type I collagen, suggesting that SFRP2 signalling in fibroblasts may contribute to propagation of fibrosis in hypertrophic scar, as well as in other clinical indications characterised by skin fibrosis.

Effectiveness of Dry Cleaning Treatments for Removing Milk Chocolate from Valve/Pipe Assemblies and Pilot-scale Chocolate Processing Equipment.

Dark chocolate produced on equipment used to manufacture milk chocolate can contain milk due to cross-contact. This study evaluated the use of dry cleaning methods for removing milk chocolate residue from a butterfly or ball valve attached to a stainless steel pipe and from pilot-scale equipment used in chocolate manufacture. Milk-free dark chocolate (40°C) was pumped through a milk chocolate-contaminated valve/pipe assembly after no cleaning, use of a pig purging treatment, or a 40°C cocoa butter flush. Dark chocolate samples were collected at 7-sec intervals. Treatments investigated for removal of residual milk chocolate from a conche and a ball mill included no cleaning, a 40°C cocoa butter rinse, and wet cleaning. After cleaning, three batches of dark chocolate (40°C) were processed in the ball mill and conche, and each batch was collected. Milk chocolate was processed on a 3-roll refiner, followed by push-through with dark chocolate (∼9 kg) with 0.3 kg samples collected at 5-min intervals. Dark chocolate samples were analyzed for milk concentrations by ELISA. Trials and analyses were completed in triplicate. Dark chocolate push-through alone resulted in milk concentrations ≥4,500 µg/g in samples obtained from the contaminated valve/pipe combinations within the first few seconds of collection, and ≥16.2 kg of dark chocolate was needed to obtain milk concentrations below the ELISA LOQ (2.5 µg/g). A pig purging treatment of the ball valve/pipe assembly resulted in milk concentrations below the ELISA LOQ. A cocoa butter flush of the butterfly valve/pipe decreased initial milk concentrations, but milk was detected until ≥18.7 kg dark chocolate purge. Milk concentrations in first batches of dark chocolate processed in a ball mill and conche without cleaning were ≥17,000 µg/g while use of a cocoa butter rinse reduced milk levels in dark chocolate by ≥89%. Some dry cleaning treatments were effective at reducing levels of milk in dark chocolate due to cross-contact.

Vertical distributions of megafauna on inactive vent sulfide features correspond to their feeding modes.

The discovery of inactive hydrothermal vent sulfide features near 9°50'N on the East Pacific Rise provides an opportunity to investigate the distribution and feeding ecology of communities inhabiting this type of habitat. We quantify megafaunal distributions on two features, Lucky's Mound and Sentry Spire, to determine how taxonomic composition and feeding traits vary with vertical elevation. Fifty-one morphotypes, categorized by feeding mode, were identified from three levels of the features (spire, apron, and base) and the surrounding flat oceanic rise. About half of the morphotypes (26 of 51) were only observed at the sulfide features. Passive suspension feeders were more abundant on the spires, where horizontal particulate flux is expected to be elevated, than the base or rise. Deposit feeders tended to be more abundant on the base and rise, where deposition is expected to be enhanced, but were unexpectedly abundant higher up on Sentry Spire. Community differences between the two sulfide features suggest that other processes, such as feature-specific chemoautotrophic production, may also influence distributions.

A dynamic flow fetal membrane organ-on-a-chip system for modeling the effects of amniotic fluid motion.

Fetal membrane (amniochorion), the innermost lining of the intrauterine cavity, surround the fetus and enclose amniotic fluid. Unlike unidirectional blood flow, amniotic fluid subtly rocks back and forth, and thus, the innermost amnion epithelial cells are continuously exposed to low levels of shear stress from fluid undulation. Here, we tested the impact of fluid motion on amnion epithelial cells (AECs) as a bearer of force impact and their potential vulnerability to cytopathologic changes that can destabilize fetal membrane functions. A previously developed amnion membrane (AM) organ-on-chip (OOC) was utilized but with dynamic flow to culture human fetal amnion membrane cells. The applied flow was modulated to perfuse culture media back and forth for 48 h to mimic fluid motion. A static culture condition was used as a negative control, and oxidative stress (OS) condition was used as a positive control representing pathophysiological changes. The impacts of fluidic motion were evaluated by measuring cell viability, cellular transition, and inflammation. Additionally, scanning electron microscopy (SEM) imaging was performed to observe microvilli formation. The results show that regardless of the applied flow rate, AECs and AMCs maintained their viability, morphology, innate meta-state, and low production of pro-inflammatory cytokines. E-cadherin expression and microvilli formation in the AECs were upregulated in a flow rate-dependent fashion; however, this did not impact cellular morphology or cellular transition or inflammation. OS treatment induced a mesenchymal morphology, significantly higher vimentin to cytokeratin 18 (CK-18) ratio, and pro-inflammatory cytokine production in AECs, whereas AMCs did not respond in any significant manner. Fluid motion and shear stress, if any, did not impact AEC cell function and did not cause inflammation. Thus, when using an amnion membrane OOC model, the inclusion of a dynamic flow environment is not necessary to mimic in utero physiologic cellular conditions of an amnion membrane.