Development of oxidative stress-associated disease models using feto-maternal interface organ-on-a-chip.

Oxidative stress (OS) and inflammation arising from cellular derangements at the fetal membrane-decidual interface (feto-maternal interface [FMi]) is a major antecedent to preterm birth (PTB). However, it is impractical to study OS-associated FMi disease state during human pregnancy, and thus it is difficult to develop strategies to reduce the incidences of PTB. A microfluidic organ-on-chip model (FMi-OOC) that mimics the in vivo structure and functions of FMi in vitro was developed to address this challenge. The FMi-OOC contained fetal (amnion epithelial, mesenchymal, and chorion) and maternal (decidua) cells cultured in four compartments interconnected by arrays of microchannels to allow independent but interconnected co-cultivation. Using this model, we tested the effects of OS and inflammation on both fetal (fetal → maternal) and maternal (maternal → fetal) sides of the FMi and determined their differential impact on PTB-associated pathways. OS was induced using cigarette smoke extract (CSE) exposure. The impacts of OS were assessed by measuring cell viability, disruption of immune homeostasis, epithelial-to-mesenchymal transition (EMT), development of senescence, and inflammation. CSE propagated (LC/MS-MS analysis for nicotine) over a 72-hour period from the maternal to fetal side, or vice versa. However, they caused two distinct pathological effects on the maternal and fetal cells. Specifically, fetal OS induced cellular pathologies and inflammation, whereas maternal OS caused immune intolerance. The pronounced impact produced by the fetus supports the hypothesis that fetal inflammatory response is a mechanistic trigger for parturition. The FMi disease-associated changes identified in the FMi-OOC suggest the unique capability of this in vitro model in testing in utero conditions.

Uniform sized cancer spheroids production using hydrogel-based droplet microfluidics: a review.

Three-dimensional (3D) cell culture models have been extensively utilized in various mechanistic studies as well as for drug development studies as superior in vitro platforms than conventional two-dimensional (2D) cell culture models. This is especially the case in cancer biology, where 3D cancer models, such as spheroids or organoids, have been utilized extensively to understand the mechanisms of cancer development. Recently, many sophisticated 3D models such as organ-on-a-chip models are emerging as advanced in vitro models that can more accurately mimic the in vivo tissue functions. Despite such advancements, spheroids are still considered as a powerful 3D cancer model due to the relatively simple structure and compatibility with existing laboratory instruments, and also can provide orders of magnitude higher throughput than complex in vitro models, an extremely important aspects for drug development. However, creating well-defined spheroids remain challenging, both in terms of throughputs in generation as well as reproducibility in size and shape that can make it challenging for drug testing applications. In the past decades, droplet microfluidics utilizing hydrogels have been highlighted due to their potentials. Importantly, core-shell structured gel droplets can avoid spheroid-to-spheroid adhesion that can cause large variations in assays while also enabling long-term cultivation of spheroids with higher uniformity by protecting the core organoid area from external environment while the outer porous gel layer still allows nutrient exchange. Hence, core-shell gel droplet-based spheroid formation can improve the predictivity and reproducibility of drug screening assays. This review paper will focus on droplet microfluidics-based technologies for cancer spheroid production using various gel materials and structures. In addition, we will discuss emerging technologies that have the potential to advance the production of spheroids, prospects of such technologies, and remaining challenges.

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.

Mediating role of self-efficacy between unmet needs and quality of life in palliative cancer caregivers.

OBJECTIVE: Although unmet support needs are associated with health-related quality of life (HRQOL) in cancer caregivers, little is known about the mechanism underlying the relationship between two variables. The self-efficacy (SE) theory and literature suggest that caregiving SE is important in the perception of and reaction to caregiving demands, which in turn affects HRQOL. The aim of this study was to examine whether caregiving SE mediates the relationship between unmet support needs and HRQOL in family caregivers of palliative cancer patients. METHODS: This secondary analysis used the data from 125 family caregivers of palliative cancer patients who were recruited from two public hospitals in Hong Kong. The caregivers completed a survey questionnaire that covered socio-demographic characteristics, unmet support needs, caregiving SE, and HRQOL. Parallel mediation analyses were conducted via SPSS PROCESS macro (Model 4) to test the hypothesized models. RESULTS: The direct effect of unmet support needs on mental HRQOL was significant (effect = -0.49, 95% CI = -0.06 to -0.92). For the indirect effect, only caregiving SE in the domain of 'care for the care recipient' mediated the relationship between unmet support needs and mental HRQOL (effect = -0.32, 95% CI = -0.08 to -0.59). CONCLUSION: The findings suggest that caregiving SE may function as a mechanism through which unmet support needs influence mental HRQOL in family caregivers of palliative cancer patients. Healthcare providers should consider developing supportive care interventions to improve caregivers' HRQOL by incorporating effective strategies to enhance SE and reduce unmet needs for this population.

Lamina cribrosa vessel and collagen beam networks are distinct.

Our goal was to analyze the spatial interrelation between vascular and collagen networks in the lamina cribrosa (LC). Specifically, we quantified the percentages of collagen beams with/without vessels and of vessels inside/outside of collagen beams. To do this, the vasculature of six normal monkey eyes was labeled by perfusion post-mortem. After enucleation, coronal cryosections through the LC were imaged using fluorescence and polarized light microscopy to visualize the blood vessels and collagen beams, respectively. The images were registered to form 3D volumes. Beams and vessels were segmented, and their spatial interrelationship was quantified in 3D. We found that 22% of the beams contained a vessel (range 14%-32%), and 21% of vessels were outside beams (13%-36%). Stated differently, 78% of beams did not contain a vessel (68%-86%), and 79% of vessels were inside a beam (64%-87%). Individual monkeys differed significantly in the fraction of vessels outside beams (p < 0.01 by linear mixed effect analysis), but not in the fraction of beams with vessels (p > 0.05). There were no significant differences between contralateral eyes in the percent of beams with vessels and of vessels outside beams (p > 0.05). Our results show that the vascular and collagenous networks of the LC in monkey are clearly distinct, and the historical notions that each LC beam contains a vessel and all vessels are within beams are inaccurate. We postulate that vessels outside beams may be relatively more vulnerable to mechanical compression by elevated IOP than are vessels shielded inside of beams.

Reliability, validity and acceptability of the traditional Chinese version of the carer support needs assessment tool in Hong Kong palliative care settings.

BACKGROUND: Among the few existing needs assessment tools for family carers, the 14-item Carer Support Needs Assessment Tool (CSNAT) is the only brief and holistic needs screening tool designed for everyday use in palliative care practices. The aim of this study was to evaluate the reliability, validity, and acceptability of the traditional Chinese version of the CSNAT in palliative care settings in Hong Kong. METHODS: This adopted a cross-sectional and correlation design with repeated measures. The participants were 125 family carers of palliative cancer patients and 10 healthcare providers (HCPs) that were recruited from two local hospitals. The evaluation of psychometric properties included the following: (1) content validity through HCPs including frontline physicians, nurses, social workers, and clinical psychologists; (2) construct validity between the CSNAT items and those of the validated tools that measured caregiver burden, social support, and caregiving self-efficacy; and (3) one-week test-retest reliability in a sub-sample of 81 caregivers. The acceptability of the tool was assessed by the carers using several closed-ended questions. RESULTS: The content validity index of the CSNAT at the scale level was 0.98. Each item of the CSNAT was significantly and moderately correlated with caregiver burden (Spearman's r = 0.24 to 0.50) and caregiving self-efficacy (r = - 0.21 to - 0.52), but not for social support. All CSNAT items had fair to moderate test-retest reliability (weighted kappa = 0.21 to 0.48), with the exception of two items "managing your relatives' symptoms, including giving medicines" and "having time for yourself in the day". Regarding the acceptability of the CSNAT, almost all HCPs were willing to use the CSNAT for carer assessment and support. 89.6% of the carers demonstrated a comprehensibility of the CSNAT tool and 92.9% felt comfortable answering the questions. Around 90% of the carers agreed to use the tool for screening, discussing needs, and making referrals. CONCLUSION: The traditional Chinese version of the CSNAT is a tool with high validity and acceptability and adequate reliability that measures family carers' support needs, which should be considered for wide application in local palliative care practices.

Effects of rubble zones from oyster cultivation on habitat utilization and foraging behaviour of the endangered tri-spine horseshoe crab: An implication for intertidal oyster cultivation practices.

Estuarine structured habitats, including benthic cultivation structure, are widely cited as substantial nursery and feeding grounds for fish and macroinvertebrates. Activities such as locomotion and foraging behaviour of sediment-dwelling species, however, may be hindered in the presence of the obstacles. In this study, collected field evidence demonstrated that habitat utilization of the juvenile tri-spine horseshoe crab Tachypleus tridentatus, an iconic and endangered macroinvertebrate, was adversely affected by high-density intertidal oyster rubble zones. Despite the fact that the utilization area of individual juvenile horseshoe crabs was independent of the presence of these obstacles, the abundance and number of positional fixes of tagged juveniles in these areas were lower. The effects of these obstacles and their associated topographic changes on the movement of the juvenile horseshoe crabs was investigated in a simulated laboratory experiment. Both the simulated oyster cultches and hummocks formed between the cultches reduced the total distance and displacement of the feeding trail, and less juveniles preferred to forage on elevated, dry hummocks (dry at low tide) formed between the cultches. Our findings suggested that oyster cultches and rubbles reduced the habitat quality for juvenile horseshoe crabs. On-bottom oyster cultivation activities seeking to conserve horseshoe cabs by avoiding nursery habitats should instead consider off-bottom or offshore cultivation methods.

Cost-effectiveness of a transitional home-based palliative care program for patients with end-stage heart failure.

BACKGROUND: Studies have shown positive clinical outcomes of specialist palliative care for end-stage heart failure patients, but cost-effectiveness evaluation is lacking. AIM: To examine the cost-effectiveness of a transitional home-based palliative care program for patients with end-stage heart failure patients as compared to the customary palliative care service. DESIGN: A cost-effectiveness analysis was conducted alongside a randomized controlled trial (Trial number: NCT02086305). The costs included pre-program training, intervention, and hospital use. Quality of life was measured using SF-6D. SETTING/PARTICIPANTS: The study took place in three hospitals in Hong Kong. The inclusion criteria were meeting clinical indicators for end-stage heart failure patients including clinician-judged last year of life, discharged to home within the service area, and palliative care referral accepted. A total of 84 subjects (study = 43, control = 41) were recruited. RESULTS: When the study group was compared to the control group, the net incremental quality-adjusted life years gain was 0.0012 (28 days)/0.0077 (84 days) and the net incremental costs per case was -HK$7935 (28 days)/-HK$26,084 (84 days). The probability of being cost-effective was 85% (28 days)/100% (84 days) based on the cost-effectiveness thresholds recommended both by National Institute for Health and Clinical Excellence (£20,000/quality-adjusted life years) and World Health Organization (Hong Kong gross domestic product/capita in 2015, HK$328117). CONCLUSION: Results suggest that a transitional home-based palliative care program is more cost-effective than customary palliative care service. Limitations of the study include small sample size, study confined to one city, clinic consultation costs, and societal costs including patient costs and unpaid care-giving costs were not included.

Retrospective review of lupus nephritis in a New Zealand multi-ethnic cohort.

Increased lupus nephritis has been reported in Pacific Island and Maori populations. Previous studies suggest ethnic variation in response to immunosuppression treatment; however this has not been assessed in Pacific Island and Maori cohorts. This retrospective study reviewed class 3, 4 and 5 lupus nephritis outcomes and response to induction immunosuppression over a 10-year period in a New Zealand multi-ethnic cohort with high Pacific Island representation. This included 49 renal biopsies in 41 patients; by ethnicity Pacific Island 53.7%, Asian 31.7%, Caucasian 12.2%, and New Zealand Maori 2.4%. There were 11 class 3, 24 class 4 and 17 class 5 either alone or in combination with class 3/4. There were no statistically significant differences in renal function or proteinuria between ethnic groups at baseline. Pacific Island class 3/4 showed similar rates of renal remission with intravenous cyclophosphamide (6/8) and mycophenolate (4/7) induction treatment; results were comparable to the overall study group. There were no deaths or permanent dialysis requirements in the first six months of treatment, and no increased risk of adverse outcomes when stratified by ethnicity. Five lupus nephritis relapses occurred during maintenance treatment and there was no apparent ethnicity bias. CONCLUSION: Pacific Island people disproportionately present with increased lupus nephritis; and had comparable renal remission rates with intravenous cyclophosphamide and oral mycophenolate which were similar to the whole study cohort.

Predictors of influenza among older adults in the emergency department.

BACKGROUND: Diagnosis of influenza in older adults may be complicated by atypical presentations or when patients present with complications of an underlying illness. We aimed to identify clinical characteristics and epidemiological factors associated with influenza among community-dwelling adults aged ≥60 years presenting to emergency departments. METHODS: We identified patients with influenza-compatible chief complaints presenting to emergency departments of six acute care hospitals in Ontario, Canada during the 2011/12 and 2012/13 influenza seasons. Clinical characteristics, medical history and demographics were collected by patient interview, chart review and by contacting vaccine providers. Nasopharyngeal swabs were tested for influenza using polymerase chain reaction. We modeled predictors of influenza using multivariable logistic regression models that compared individuals with and without influenza. RESULTS: Of 1318 participants, 151 (11 %) had influenza (98 A/H3N2, 12 A/H1N1, 4 A [not sub-typed], 37 B). In the multivariable model, clinical symptoms associated with influenza were cough (OR 6.4, 95 % CI 3.2, 13.0), feverishness and/or triage temperature ≥37.2 °C (OR 3.0, 95 % CI 2.0, 4.7), 2-5 days from symptom onset to the emergency department visit (OR 2.2, 95 % CI 1.5, 3.2), and wheezing (OR 2.1, 95 % CI 1.3, 3.3). The effect of cough on influenza increased with older age. Epidemiological factors associated with increased odds for influenza included weeks when ≥10 % influenza tests from provincial laboratories were positive (OR 5.1, 95 % CI 1.2, 21.7) and exposure to a person with influenza-like illness (OR 1.9, 95 % CI 1.3, 2.8). Among participants with influenza, only 47 (31 %) met the U.S. Centers for Disease Control and Prevention criteria for influenza-like illness (temperature ≥37.8 °C and cough and/or sore throat). CONCLUSIONS: As in younger adults, cough and feverishness are the two symptoms most predictive of influenza in the elderly. Current influenza-like illness definitions did not adequately capture influenza in older adults.

Comparison of peritoneal dialysis catheter insertion techniques: Peritoneoscopic, radiological and laparoscopic : A single-centre study.

BACKGROUND: Our centre introduced peritoneoscopic insertion of peritoneal dialysis (PD) catheter by nephrologists as a new method in August 2009 for its potential benefits. AIM: The aim of this study was to compare perioperative complications and catheter survival of three techniques: peritoneoscopic, surgical and radiological techniques within a single dialysis centre. METHOD: This study used retrospective analysis of all PD catheter inserted from 1 August 2009 to 31 July 2013 within Counties Manukau DHB, Auckland, New Zealand. RESULTS: During the study period, 293 PD catheters were inserted, 84 (29%) peritoneoscopic (P), 140 (48%) surgical (S) and 69 (23%) radiological (R). Total duration of follow-up was 5848 catheter-months, with median follow-up of 17 months. There was no difference in perioperative exit-site infections and overall early infections. There was however increased overall perioperative complications in P compared with R (HR 2.08; P < 0.05), predominantly from catheter removal within 60 days. Although there was no difference observed in first catheter 1-year and overall survival between insertion techniques, there was poorer complication-free survival comparing P to S (HR 1.82, P = 0.001) but not to R. Analyses of the latter cohort of P confirmed improvement in catheter survival compared with an earlier cohort and to other insertion techniques. CONCLUSION: Peritoneoscopic PD catheter insertion is demonstrated to be a suitable alternative technique. As with any new procedure, 'learning curve' effects and development of operator expertise need to be taken into consideration.

Herd effect from influenza vaccination in non-healthcare settings: a systematic review of randomised controlled trials and observational studies.

Influenza vaccination programmes are assumed to have a herd effect and protect contacts of vaccinated persons from influenza virus infection. We searched MEDLINE, EMBASE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Global Health and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception to March 2014 for studies assessing the protective effect of influenza vaccination vs no vaccination on influenza virus infections in contacts. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) using a random-effects model. Of 43,082 screened articles, nine randomised controlled trials (RCTs) and four observational studies were eligible. Among the RCTs, no statistically significant herd effect on the occurrence of influenza in contacts could be found (OR: 0.62; 95% CI: 0.34-1.12). The one RCT conducted in a community setting, however, showed a significant effect (OR: 0.39; 95% CI: 0.26-0.57), as did the observational studies (OR: 0.57; 95% CI: 0.43-0.77). We found only a few studies that quantified the herd effect of vaccination, all studies except one were conducted in children, and the overall evidence was graded as low. The evidence is too limited to conclude in what setting(s) a herd effect may or may not be achieved.

Evaluation of a cooking skills programme in parents of young children--a longitudinal study.

OBJECTIVE: To evaluate longitudinally the effectiveness of a cooking programme on self-reported confidence about cooking skills and food consumption patterns in parents of young children. DESIGN: An evaluation of cooking programmes delivered by National Health Service (NHS) community food workers using a single group pre-test/post-test repeated measures design. A shortened version of a validated questionnaire at baseline, post intervention and 1-year follow-up determined confidence in cooking using basic ingredients, following a simple recipe, tasting new foods, preparing and cooking new foods on consumption of ready meals, vegetables and fruit. SETTING: Deprived communities in Ayrshire and Arran, Scotland. SUBJECTS: Parents of nursery age children, 97 % were female and <45 years old. RESULTS: One hundred and two participants had completed baseline and post-intervention questionnaires. Forty-four participants contacted by telephone completed a follow-up questionnaire. In participants who completed all questionnaires (n 44), median confidence in four aspects of cooking increased significantly from baseline to post intervention (P < 0·001) but was retained at 1-year follow-up only for following a simple recipe and preparing and cooking new foods. Improved food consumption patterns were reported from baseline to post intervention (ready-meal consumption reduced from 2-4 times/week to 1 time/week, P < 0·001; vegetable consumption increased from 5-6 times/week to 1 time/d, P < 0·001; fruit consumption increased from 5-6 times/week to 1 time/d, P < 0·001) and remained at 1-year follow-up. CONCLUSIONS: The cooking programmes appeared to improve cooking confidence and food consumption patterns in the target group and some of these changes were retained after 1 year.

Extended high cut-off haemodialysis for myeloma cast nephropathy in Auckland, 2008-2012.

Myeloma cast nephropathy contributes to high morbidity and early mortality associated with the development of end-stage renal disease. Treatment with extended high cut-off haemodialysis coupled with novel anti-myeloma therapies enables significant reduction of serum-free light chains and has been shown to improve renal outcomes. In this case series, medical records of 6 patients who received high cut-off haemodialysis for biopsy-proven cast nephropathy were retrospectively reviewed. Patients received a total of 344 hours of high cut-off haemodialysis and concurrent chemotherapy. Only 50% became dialysis independent following treatment. One patient who achieved sustained remission remained dialysis dependent. The added benefit of high cut-off haemodialysis in the light of novel anti-myeloma therapies requires further evaluation.

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. An amnion membrane (AM) organ-on-chip (OOC) was utilized to culture human fetal amnion membrane cells. The applied flow was modulated to perfuse culture media back and forth for 48 hours flow culture to mimic fluid motion. Static culture condition was used as a negative control, and oxidative stress (OS) condition was used as a positive control for 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 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 flow culture environment is not necessary to mimic any in utero physiologic cellular conditions of fetal membrane-derived cells.

A multi-organ, feto-maternal interface organ-on-chip, models pregnancy pathology and is a useful preclinical extracellular vesicle drug trial platform.

Pregnant women and their fetuses are often excluded from clinical trials due to missing drug-related pre-clinical trial information at the human feto-maternal interface (FMi). The two interfaces-placenta/decidua and fetal membranes/decidua are gatekeepers of drug transport; however, testing their functions is impractical during pregnancy. Limitations of current in-vivo/in-vitro models have hampered drug development and testing during pregnancy. Hence, major complications like preterm births and maternal and neonatal mortalities remain high. Advancements in organ-on-chip (OOC) platforms to test drug kinetics and efficacy and novel extracellular vesicle-based fetal drug delivery are expected to accelerate preclinical trials related to pregnancy complications. Here we report the development and testing of a humanized multi-organ fetal membrane/placenta (fetal)-decidua (maternal) interface OOC (FMi-PLA-OOC) that contains seven cell types interconnected through microchannels to maintain intercellular interactions as seen in-utero. Cytotoxicity, propagation, mechanism of action, and efficacy of engineered extracellular vesicles containing anti-inflammatory interleukin (IL)-10 (eIL-10) were evaluated to reduce FMi inflammation associated with preterm birth. A healthy and disease model (lipopolysaccharide-infectious inflammation) of the FMi-PLA-OOC was created and co-treated with eIL-10. eIL-10 propagated from the maternal to fetal side within 72-hours, localized in all cell types, showed no cytotoxicity, activated IL-10 signaling pathways, and reduced lipopolysaccharide-induced inflammation (minimized NF-kB activation and proinflammatory cytokine production). These data recapitulated eIL-10s' ability to reduce inflammation and delay infection-associated preterm birth in mouse models, suggesting FMi-PLA-OOC as an alternative approach to using animal models. Additionally, we report the utility of eIL-10 that can traverse through FMis to reduce inflammation-associated pregnancy complications.

Endocrine-disrupting compounds and their impact on human placental function: evidence from placenta organ-on-chip studies.

The effects of endocrine-disrupting compounds (EDCs) on the placenta, a critical gestational organ for xenobiotic protection, are well reported; however, models to determine the role of EDCs in placental disruption are limited. An advanced 2nd-trimester human placenta organ-on-chip model (2TPLA-OOC) was developed and validated, with six representative cells of the maternal and the fetal interface interconnected with microchannels. Various EDCs (150 ng mL-1 each of bisphenol A, bisphenol S, and polybrominated diphenyl ethers-47 and -99) were gradually propagated across the chip for 72 hours, and their various effects were determined. Cigarette smoke extract (CSE), an environmental risk factor, was used as a positive control. EDCs produced overall oxidative stress in the placental/decidual cells, induced cell-specific endocrine effects, caused limited (<10%) apoptosis/necrosis in trophoblasts and mesenchymal cells, induced localized inflammation but an overall anti-inflammatory shift, did not change immune cell migration from stroma to decidua, and did not affect placental nutrient transport. Overall, (1) the humanized 2TPLA-OOC recreated the placental organ and generated data distinct from the trophoblast and other cells studied in isolation, and (2) at doses associated with adverse pregnancies, EDCs produced limited and localized insults, and the whole organ compensated for the exposure.

Dynamic composite hydrogels of gelatin methacryloyl (GelMA) with supramolecular fibers for tissue engineering applications.

In the field of tissue engineering, there is a growing need for biomaterials with structural properties that replicate the native characteristics of the extracellular matrix (ECM). It is important to include fibrous structures into ECM mimics, especially when constructing scar models. Additionally, including a dynamic aspect to cell-laden biomaterials is particularly interesting, since native ECM is constantly reshaped by cells. Composite hydrogels are developed to bring different combinations of structures and properties to a scaffold by using different types and sources of materials. In this work, we aimed to combine gelatin methacryloyl (GelMA) with biocompatible supramolecular fibers made of a small self-assembling sugar-derived molecule (N-heptyl-D-galactonamide, GalC7). The GalC7 fibers were directly grown in the GelMA through a thermal process, and it was shown that the presence of the fibrous network increased the Young's modulus of GelMA. Due to the non-covalent interactions that govern the self-assembly, these fibers were observed to dissolve over time, leading to a dynamic softening of the composite gels. Cardiac fibroblast cells were successfully encapsulated into composite gels for 7 days, showing excellent biocompatibility and fibroblasts extending in an elongated morphology, most likely in the channels left by the fibers after their degradation. These novel composite hydrogels present unique properties and could be used as tools to study biological processes such as fibrosis, vascularization and invasion.

An Instrument for High-throughput Testing of Heart Tissue In Vitro.

Cardiac trabeculae are small samples of heart muscle tissue that can be dissected and studied in vitro to better understand the underlying physiology of cardiac muscle. However, instruments for such experimentation often (1) involve delicate mounting of the muscle, (2) constrain investigations to one muscle at a time and, thus, (3) cannot retain the muscle in the same experimental configuration for post-experimental assessment including imaging analysis. Here, we present a novel device that allows trabeculae to be secured by a visible-light photo-initiated hydrogel, manipulated via a force sensor, and stimulated while being imaged. We use our robust, accurate image registration techniques to measure cantilever and gel deformation during trabecula contraction and thereby provide a measure of trabecula force production during twitches. A variety of experiments can then be conducted, with the potential for the trabecula to be fixed in place using hydrogel for further post-experiment analysis, as well as longitudinal evaluation. The device has multiple wells making it amenable to high-throughput testing.Clinical Relevance- These methods may allow longitudinal and high-throughput studies of cardiac tissue samples in health and disease.