Embedding Biomimetic Vascular Networks via Coaxial Sacrificial Writing into Functional Tissue.

Printing human tissues and organs replete with biomimetic vascular networks is of growing interest. While it is possible to embed perfusable channels within acellular and densely cellular matrices, they do not currently possess the biomimetic architectures found in native vessels. Here, coaxial sacrificial writing into functional tissues (co-SWIFT) is developed, an embedded bioprinting method capable of generating hierarchically branching, multilayered vascular networks within both granular hydrogel and densely cellular matrices. Coaxial printheads are designed with an extended core-shell configuration to facilitate robust core-core and shell-shell interconnections between printed branching vessels during embedded bioprinting. Using optimized core-shell ink combinations, biomimetic vessels composed of a smooth muscle cell-laden shell that surrounds perfusable lumens are coaxially printed into granular matrices composed of: 1) transparent alginate microparticles, 2) sacrificial microparticle-laden collagen, or 3) cardiac spheroids derived from human induced pluripotent stem cells. Biomimetic blood vessels that exhibit good barrier function are produced by seeding these interconnected lumens with a confluent layer of endothelial cells. Importantly, it is found that co-SWIFT cardiac tissues mature under perfusion, beat synchronously, and exhibit a cardio-effective drug response in vitro. This advance opens new avenues for the scalable biomanufacturing of vascularized organ-specific tissues for drug testing, disease modeling, and therapeutic use.

Informing knowledge translation for selective dorsal rhizotomy: A survey of Australian clinicians and people with lived experience of cerebral palsy.

AIM: Selective dorsal rhizotomy (SDR) is a neurosurgical intervention used to reduce spasticity in children with cerebral palsy (CP). There is minimal relevant, evidence-based information available for Australian families and clinicians. This study aims to investigate the knowledge of people with lived experience and clinicians regarding SDR, including how they currently access information and what information they seek. METHODS: Adults with CP, carers of children with CP and clinicians treating children with CP were invited to complete an online survey. Data regarding participant demographics, current knowledge and confidence in knowledge about CP and SDR, information source/s used and participants level of trust in these sources are presented as counts and percentages. Comparisons in knowledge between groups were analysed. RESULTS: A total of 114 surveys were completed: 63 clinicians, 48 carers, and 3 adults with CP. Eighty percent of clinicians were allied health professionals. People with lived experience were less confident in their knowledge about SDR compared to knowledge of CP (P < 0.001). Clinicians rated scientific research literature and the hospital team as the most useful and trustworthy information source. People with lived experience used a wider range of information sources including the internet, rating their community therapy team and other people with lived experience as the most useful. CONCLUSION: This study identified a lack of confidence in knowledge of SDR for people with lived experience, likely due to a gap in accessible and readable evidence-based information. While both groups differed in how they access information, there was agreement that greater information about SDR is needed.

A perfusable, vascularized kidney organoid-on-chip model.

The ability to controllably perfuse kidney organoids would better recapitulate the native tissue microenvironment for applications ranging from drug testing to therapeutic use. Here, we report a perfusable, vascularized kidney organoid on chip model composed of two individually addressable channels embedded in an extracellular matrix (ECM). The channels are respectively seeded with kidney organoids and human umbilical vein endothelial cells that form a confluent endothelium (macrovessel). During perfusion, endogenous endothelial cells present within the kidney organoids migrate through the ECM towards the macrovessel, where they form lumen-on-lumen anastomoses that are supported by stromal-like cells. Once micro-macrovessel integration is achieved, we introduced fluorescently labeled dextran of varying molecular weight and red blood cells into the macrovessel, which are transported through the microvascular network to the glomerular epithelia within the kidney organoids. Our approach for achieving controlled organoid perfusion opens new avenues for generating other perfused human tissues.

Lung Cancer Survival Trends in the Veterans Health Administration.

INTRODUCTION: Lung cancer survival is improving in the United States. We investigated whether there was a similar trend within the Veterans Health Administration (VHA), the largest integrated healthcare system in the United States. MATERIALS AND METHODS: Data from the Veterans Affairs Central Cancer Registry were analyzed for temporal survival trends using Kaplan-Meier estimates and linear regression. RESULTS: A total number of 54,922 Veterans were identified with lung cancer diagnosed from 2010 to 2017. Histologies were classified as non-small-cell lung cancer (NSCLC) (64.2%), small cell lung cancer (SCLC) (12.9%), and 'other' (22.9%). The proportion with stage I increased from 18.1% to 30.4%, while stage IV decreased from 38.9% to 34.6% (both P < .001). The 3-year overall survival (OS) improved for stage I (58.6% to 68.4%, P < .001), stage II (35.5% to 48.4%, P < .001), stage III (18.7% to 29.4%, P < .001), and stage IV (3.4% to 7.8%, P < .001). For NSCLC, the median OS increased from 12 to 21 months (P < .001), and the 3-year OS increased from 24.1% to 38.3% (P < .001). For SCLC, the median OS remained unchanged (8 to 9 months, P = .10), while the 3-year OS increased from 9.1% to 12.3% (P = .014). Compared to White Veterans, Black Veterans with NSCLC had similar OS (P = .81), and those with SCLC had higher OS (P = .003). CONCLUSION: Lung cancer survival is improving within the VHA. Compared to White Veterans, Black Veterans had similar or higher survival rates. The observed racial equity in outcomes within a geographically and socioeconomically diverse population warrants further investigation to better understand and replicate this achievement in other healthcare systems.

Liquid Crystal Elastomer Lattices with Thermally Programmable Deformation via Multi-Material 3D Printing.

An integrated design, modeling, and multi-material 3D printing platform for fabricating liquid crystal elastomer (LCE) lattices in both homogeneous and heterogeneous layouts with spatially programmable nematic director order and local composition is reported. Depending on their compositional topology, these lattices exhibit different reversible shape-morphing transformations upon cycling above and below their respective nematic-to-isotropic transition temperatures. Further, it is shown that there is good agreement between their experimentally observed deformation response and model predictions for all LCE lattice designs evaluated. Lastly, an inverse design model is established and the ability to print LCE lattices with the predicted deformation behavior is demonstrated. This work opens new avenues for creating architected LCE lattices that may find potential application in energy-dissipating structures, microfluidic pumping, mechanical logic, and soft robotics.

Social vulnerability and lung malignancy mortality.

INTRODUCTION: Lung cancer is a major cause of death in the United States. Social determinants of health (SDOH) are important factors that impact the treatment and prognosis of lung cancer. The social vulnerability index (SVI) is a validated measure of SDOH. This cross-sectional study aimed to investigate the impact of the SVI on lung cancer mortality using descriptive epidemiology. METHODS: Mortality data for lung malignancies from 2014 to 2018 was obtained from the CDC database and was age-adjusted and standardized to the population in the year 2000. The SVI for the same years was obtained from the CDC Agency for Toxic Substances and Disease Registry database. Age-adjusted mortality rates (AAMR) were estimated for each SVI quartile (SVI-Q) and demographic subgroup. RESULTS: We found that counties in SVI-Q4 (most vulnerable) had a higher cumulative AAMR compared to counties in SVI-Q1 (least vulnerable), accounting for a 4.48 excess death rate per 100,000 person-years. AAMR among males in SVI-Q4 was higher compared to SVI-Q1, accounting for a 9.96 excess death rate per 100,000 person-years, whereas no mortality differences were observed for female populations between SVI-Q4 and SVI-Q1. AAMR in SVI-Q4 was higher for both Hispanic and non-Hispanic populations, except for American Indian/Alaska Native populations. Similar trends were observed in both metropolitan and non-metropolitan counties. CONCLUSION: Our study suggests that the SVI may play a significant role in lung cancer mortality and highlights the need for interventions targeting vulnerable populations to improve outcomes.

Identification and Characterization of Avoidable Hospital Admissions in Patients With Lung Cancer.

BACKGROUND: More than 50% of patients with lung cancer are admitted to the hospital while receiving treatment, which is a burden to patients and the healthcare system. This study characterizes the risk factors and outcomes of patients with lung cancer who were admitted to the hospital. METHODS: A multidisciplinary oncology care team conducted a retrospective medical record review of patients with lung cancer admitted in 2018. Demographics, disease and admission characteristics, and end-of-life care utilization were recorded. Following a multidisciplinary consensus review process, admissions were determined to be either "avoidable" or "unavoidable." Generalized estimating equation logistic regression models assessed risks and outcomes associated with avoidable admissions. RESULTS: In all, 319 admissions for 188 patients with a median age of 66 years (IQR, 59-74 years) were included. Cancer-related symptoms accounted for 65% of hospitalizations. Common causes of unavoidable hospitalizations were unexpected disease progression causing symptoms, chronic obstructive pulmonary disease exacerbation, and infection. Of the 47 hospitalizations identified as avoidable (15%), the median overall survival was 1.6 months compared with 9.7 months (hazard ratio, 2.07; 95% CI, 1.34-3.19; P<.001) for unavoidable hospitalizations. Significant reasons for avoidable admissions included cancer-related pain (P=.02), hypervolemia (P=.03), patient desire to initiate hospice services (P=.01), and errors in medication reconciliation or distribution (P<.001). Errors in medication management caused 26% of the avoidable hospitalizations. Of admissions in patients receiving immunotherapy (n=102) or targeted therapy (n=44), 9% were due to adverse effects of treatment. Patients receiving immunotherapy and targeted therapy were at similar risk of avoidable hospitalizations compared with patients not receiving treatment (P=.3 and P=.1, respectively). CONCLUSIONS: We found that 15% of hospitalizations among patients with lung cancer were potentially avoidable. Uncontrolled symptoms, delayed implementation of end-of-life care, and errors in medication reconciliation were associated with avoidable inpatient admissions. Symptom management tools, palliative care integration, and medication reconciliations may mitigate hospitalization risk.

Rural barriers and facilitators of lung cancer screening program implementation in the veterans health administration: a qualitative study.

Introduction: To assess healthcare professionals' perceptions of rural barriers and facilitators of lung cancer screening program implementation in a Veterans Health Administration (VHA) setting through a series of one-on-one interviews with healthcare team members. Methods: Based on measures developed using Reach Effectiveness Adoption Implementation Maintenance (RE-AIM), we conducted a cross-sectional qualitative study consisting of one-on-one semi-structured telephone interviews with VHA healthcare team members at 10 Veterans Affairs medical centers (VAMCs) between December 2020 and September 2021. An iterative inductive and deductive approach was used for qualitative analysis of interview data, resulting in the development of a conceptual model to depict rural barriers and facilitators of lung cancer screening program implementation. Results: A total of 30 interviews were completed among staff, providers, and lung cancer screening program directors and a conceptual model of rural barriers and facilitators of lung cancer screening program implementation was developed. Major themes were categorized within institutional and patient environments. Within the institutional environment, participants identified systems-level (patient communication, resource availability, workload), provider-level (attitudes and beliefs, knowledge, skills and capabilities), and external (regional and national networks, incentives) barriers to and facilitators of lung cancer screening program implementation. Within the patient environment, participants revealed patient-level (modifiable vulnerabilities) barriers and facilitators as well as ecological modifiers (community) that influence screening behavior. Discussion: Understanding rural barriers to and facilitators of lung cancer screening program implementation as perceived by healthcare team members points to opportunities and approaches for improving lung cancer screening reach, implementation and effectiveness in VHA rural settings.

Biomimetic human skin model patterned with rete ridges.

Rete ridges consist of undulations between the epidermis and dermis that enhance the mechanical properties and biological function of human skin. However, most human skin models are fabricated with a flat interface between the epidermal and dermal layers. Here, we report a micro-stamping method for producing human skin models patterned with rete ridges of controlled geometry. To mitigate keratinocyte-induced matrix degradation, telocollagen-fibrin matrices with and without crosslinks enable these micropatterned features to persist during longitudinal culture. Our human skin model exhibits an epidermis that includes the following markers: cytokeratin 14, p63, and Ki67 in the basal layer, cytokeratin 10 in the suprabasal layer, and laminin and collagen IV in the basement membrane. We demonstrated that two keratinocyte cell lines, one from a neonatal donor and another from an adult diabetic donor, are compatible with this model. We tested this model using an irritation test and showed that the epidermis prevents rapid penetration of sodium dodecyl sulfate. Gene expression analysis revealed differences in keratinocytes obtained from the two donors as well as between 2D (control) and 3D culture conditions. Our human skin model may find potential application for drug and cosmetic testing, disease and wound healing modeling, and aging studies.

Immune-infiltrated kidney organoid-on-chip model for assessing T cell bispecific antibodies.

T cell bispecific antibodies (TCBs) are the focus of intense development for cancer immunotherapy. Recently, peptide-MHC (major histocompatibility complex)-targeted TCBs have emerged as a new class of biotherapeutics with improved specificity. These TCBs simultaneously bind to target peptides presented by the polymorphic, species-specific MHC encoded by the human leukocyte antigen (HLA) allele present on target cells and to the CD3 coreceptor expressed by human T lymphocytes. Unfortunately, traditional models for assessing their effects on human tissues often lack predictive capability, particularly for "on-target, off-tumor" interactions. Here, we report an immune-infiltrated, kidney organoid-on-chip model in which peripheral blood mononuclear cells (PBMCs) along with nontargeting (control) or targeting TCB-based tool compounds are circulated under flow. The target consists of the RMF peptide derived from the intracellular tumor antigen Wilms' tumor 1 (WT1) presented on HLA-A2 via a bivalent T cell receptor-like binding domain. Using our model, we measured TCB-mediated CD8+ T cell activation and killing of RMF-HLA-A2-presenting cells in the presence of PBMCs and multiple tool compounds. DP47, a non-pMHC-targeting TCB that only binds to CD3 (negative control), does not promote T cell activation and killing. Conversely, the nonspecific ESK1-like TCB (positive control) promotes CD8+ T cell expansion accompanied by dose-dependent T cell-mediated killing of multiple cell types, while WT1-TCB* recognizing the RMF-HLA-A2 complex with high specificity, leads solely to selective killing of WT1-expressing cells within kidney organoids under flow. Our 3D kidney organoid model offers a platform for preclinical testing of cancer immunotherapies and investigating tissue-immune system interactions.

3D vascularised proximal tubules-on-a-multiplexed chip model for enhanced cell phenotypes.

Modelling proximal tubule physiology and pharmacology is essential to understand tubular biology and guide drug discovery. To date, multiple models have been developed; however, their relevance to human disease has yet to be evaluated. Here, we report a 3D vascularized proximal tubule-on-a-multiplexed chip (3DvasPT-MC) device composed of co-localized cylindrical conduits lined with confluent epithelium and endothelium, embedded within a permeable matrix, and independently addressed by a closed-loop perfusion system. Each multiplexed chip contains six 3DvasPT models. We performed RNA-seq and compared the transcriptomic profile of proximal tubule epithelial cells (PTECs) and human glomerular endothelial cells (HGECs) seeded in our 3D vasPT-MCs and on 2D transwell controls with and without a gelatin-fibrin coating. Our results reveal that the transcriptional profile of PTECs is highly dependent on both the matrix and flow, while HGECs exhibit greater phenotypic plasticity and are affected by the matrix, PTECs, and flow. PTECs grown on non-coated Transwells display an enrichment of inflammatory markers, including TNF-a, IL-6, and CXCL6, resembling damaged tubules. However, this inflammatory response is not observed for 3D proximal tubules, which exhibit expression of kidney signature genes, including drug and solute transporters, akin to native tubular tissue. Likewise, the transcriptome of HGEC vessels resembled that of sc-RNAseq from glomerular endothelium when seeded on this matrix and subjected to flow. Our 3D vascularized tubule on chip model has utility for both renal physiology and pharmacology.

The Association of Organizational Readiness With Lung Cancer Screening Utilization.

INTRODUCTION: Lung cancer screening is widely underutilized. Organizational factors, such as readiness for change and belief in the value of change (change valence), may contribute to underutilization. The aim of this study was to evaluate the association between healthcare organizations' preparedness and lung cancer screening utilization. METHODS: Investigators cross-sectionally surveyed clinicians, staff, and leaders at10 Veterans Affairs from November 2018 to February 2021 to assess organizational readiness to implement change. In 2022, investigators used simple and multivariable linear regression to evaluate the associations between facility-level organizational readiness to implement change and change valence with lung cancer screening utilization. Organizational readiness to implement change and change valence were calculated from individual surveys. The primary outcome was the proportion of eligible Veterans screened using low-dose computed tomography. Secondary analyses assessed scores by healthcare role. RESULTS: The overall response rate was 27.4% (n=1,049), with 956 complete surveys analyzed: median age of 49 years, 70.3% female, 67.6% White, 34.6% clinicians, 61.1% staff, and 4.3% leaders. For each 1-point increase in median organizational readiness to implement change and change valence, there was an associated 8.4-percentage point (95% CI=0.2, 16.6) and a 6.3-percentage point increase in utilization (95% CI= -3.9, 16.5), respectively. Higher clinician and staff median scores were associated with increased utilization, whereas leader scores were associated with decreased utilization after adjusting for other roles. CONCLUSIONS: Healthcare organizations with higher readiness and change valence utilized more lung cancer screening. These results are hypothesis generating. Future interventions to increase organizations' preparedness, especially among clinicians and staff, may increase lung cancer screening utilization.

Microporogen-Structured Collagen Matrices for Embedded Bioprinting of Tumor Models for Immuno-Oncology.

Embedded bioprinting enables the rapid design and fabrication of complex tissues that recapitulate in vivo microenvironments. However, few biological matrices enable good print fidelity, while simultaneously facilitate cell viability, proliferation, and migration. Here, a new microporogen-structured (µPOROS) matrix for embedded bioprinting is introduced, in which matrix rheology, printing behavior, and porosity are tailored by adding sacrificial microparticles composed of a gelatin-chitosan complex to a prepolymer collagen solution. To demonstrate its utility, a 3D tumor model is created via embedded printing of a murine melanoma cell ink within the µPOROS collagen matrix at 4 °C. The collagen matrix is subsequently crosslinked around the microparticles upon warming to 21 °C, followed by their melting and removal at 37 °C. This process results in a µPOROS matrix with a fibrillar collagen type-I network akin to that observed in vivo. Printed tumor cells remain viable and proliferate, while antigen-specific cytotoxic T cells incorporated in the matrix migrate to the tumor site, where they induce cell death. The integration of the µPOROS matrix with embedded bioprinting opens new avenues for creating complex tissue microenvironments in vitro that may find widespread use in drug discovery, disease modeling, and tissue engineering for therapeutic use.

National Survey of Lung Cancer Screening Practices in Veterans Health Administration Facilities.

INTRODUCTION: Lung cancer screening can save lives through the early detection of lung cancer, and professional societies recommend key lung cancer screening program components to ensure high-quality screening. Yet, little is known about the key components that comprise the various screening program models in routine clinical settings. The objective was to compare the utilization of these key components across centralized, hybrid, and decentralized lung cancer screening programs. METHODS: The survey was designed to identify current structures and processes of lung cancer screening programs. It was administered electronically to Veterans Health Administration facilities nationally (N=122) between August and December 2021. Results were analyzed between March and August 2022 and stratified by self-identified lung cancer screening program type, and we tested the hypothesis that centralized screening programs would be more likely to have implemented practices that support lung cancer screening, followed by hybrid and decentralized programs, using the Cochran-Armitage trend test. RESULTS: Overall, 69 (56.6%) facilities completed the survey, and respondents were lung cancer screening coordinators (39.1%), pulmonologists (33.3%), and oncologists (10.1%). Facilities most frequently self-identified as having a centralized (37.7%) program model, followed by identifying as having hybrid (30.4%) and decentralized (20.3%) programs. There was varying implementation of practices to support lung cancer screening, with hybrid and decentralized programs less likely to have lung cancer screening registries, lung cancer screening steering committees, or dedicated lung cancer screening coordinators. CONCLUSIONS: Although there is overlap between the components of various lung cancer screening program types, centralized programs more frequently implemented practices before the initial screening to support lung cancer screening. This work provides a path for future investigations to identify which lung cancer screening practices are effective to improve lung cancer screening outcomes, which could help inform implementation in settings with limited resources.

Design of medical tympanostomy conduits with selective fluid transport properties.

Implantable tubes, shunts, and other medical conduits are crucial for treating a wide range of conditions from ears and eyes to brain and liver but often impose serious risks of device infection, obstruction, migration, unreliable function, and tissue damage. Efforts to alleviate these complications remain at an impasse because of fundamentally conflicting design requirements: Millimeter-scale size is required to minimize invasiveness but exacerbates occlusion and malfunction. Here, we present a rational design strategy that reconciles these trade-offs in an implantable tube that is even smaller than the current standard of care. Using tympanostomy tubes (ear tubes) as an exemplary case, we developed an iterative screening algorithm and show how unique curved lumen geometries of the liquid-infused conduit can be designed to co-optimize drug delivery, effusion drainage, water resistance, and biocontamination/ingrowth prevention in a single subcapillary-length-scale device. Through extensive in vitro studies, we demonstrate that the engineered tubes enabled selective uni- and bidirectional fluid transport; nearly eliminated adhesion and growth of common pathogenic bacteria, blood, and cells; and prevented tissue ingrowth. The engineered tubes also enabled complete eardrum healing and hearing preservation and exhibited more efficient and rapid antibiotic delivery to the middle ear in healthy chinchillas compared with current tympanostomy tubes, without resulting in ototoxicity at up to 24 weeks. The design principle and optimization algorithm presented here may enable tubes to be customized for a wide range of patient needs.

Black Women's Perspectives on Breast Cancer Risk Assessment.

PURPOSE: The aim of this study was to gather the perspectives of Black women on breast cancer risk assessment through a series of one-on-one interviews. METHODS: The authors conducted a cross-sectional qualitative study consisting of one-on-one semistructured telephone interviews with Black women in Tennessee between September 2020 and November 2020. Guided by the Health Belief Model, qualitative analysis of interview data was performed in an iterative inductive and deductive approach and resulted in the development of a conceptual framework to depict influences on a woman's decision to engage with breast cancer risk assessment. RESULTS: A total of 37 interviews were completed, and a framework of influences on a woman's decision to engage in breast cancer risk assessment was developed. Study participants identified several emerging themes regarding women's perspectives on breast cancer risk assessment and potential influences on women's decisions to engage with risk assessment. Much of women's decision context was based on risk appraisal (perceived severity of cancer and susceptibility of cancer), emotions (fear and trust), and perceived risks and benefits of having risk assessment. The decision was further influenced by modifiers such as communication, the risk assessment protocol, access to health care, knowledge, and health status. Perceived challenges to follow-up if identified as high risk also influenced women's decisions to pursue risk assessment. CONCLUSIONS: Black women in this study identified several barriers to engagement with breast cancer risk assessment. Efforts to overcome these barriers and increase the use of breast cancer risk assessment can potentially serve as a catalyst to address existing breast cancer disparities. Continued work is needed to develop patient-centric strategies to overcome identified barriers.

Barriers to Implementation of Breast Cancer Risk Assessment: The Health Care Team Perspective.

PURPOSE: To assess health care professionals' perceptions of barriers to the utilization of breast cancer risk assessment tools in the public health setting through a series of one-on-one interviews with health care team members. METHODS: We conducted a cross-sectional qualitative study consisting of one-on-one semistructured telephone interviews with health care team members in the public health setting in the state of Tennessee between May 2020 and October 2020. An iterative inductive-deductive approach was used for qualitative analysis of interview data, resulting in the development of a conceptual framework to depict influences of provider behavior in the utilization of breast cancer risk assessment. RESULTS: A total of 24 interviews were completed, and a framework of influences of provider behavior in the utilization of breast cancer risk assessment was developed. Participants identified barriers to the utilization of breast cancer risk assessment (knowledge and understanding of risk assessment tools, workflow challenges, and availability of personnel); patient-level barriers as perceived by health care team members (psychological, economic, educational, and environmental); and strategies to increase the utilization of breast cancer risk assessment at the provider level (leadership buy-in, training, supportive policies, and incentives) and patient level (improved communication and better understanding of patients' perceived cancer risk and severity of cancer). CONCLUSIONS: Understanding barriers to implementation of breast cancer risk assessment and strategies to overcome these barriers as perceived by health care team members offers an opportunity to improve implementation of risk assessment and to identify a racially, geographically, and socioeconomically diverse population of young women at high risk for breast cancer.

Functional maturation of kidney organoid tubules: PIEZO1-mediated Ca2+ signaling.

Kidney organoids cultured on adherent matrices in the presence of superfusate flow generate vascular networks and exhibit more mature podocyte and tubular compartments compared with static controls (Homan KA, Gupta N, Kroll KT, Kolesky DB, Skylar-Scott M, Miyoshi T, Mau D, Valerius MT, Ferrante T, Bonventre JV, Lewis JA, Morizane R. Nat Methods 16: 255-262, 2019; Takasato M, Er PX, Chiu HS, Maier B, Baillie GJ, Ferguson C, Parton RG, Wolvetang EJ, Roost MS, Chuva de Sousa Lopes SM, Little MH. Nature 526: 564-568, 2015.). However, their physiological function has yet to be systematically investigated. Here, we measured mechano-induced changes in intracellular Ca2+ concentration ([Ca2+]i) in tubules isolated from organoids cultured for 21-64 days, microperfused in vitro or affixed to the base of a specimen chamber, and loaded with fura-2 to measure [Ca2+]i. A rapid >2.5-fold increase in [Ca2+]i from a baseline of 195.0 ± 22.1 nM (n = 9; P ≤ 0.001) was observed when microperfused tubules from organoids >40 days in culture were subjected to luminal flow. In contrast, no response was detected in tubules isolated from organoids <30 days in culture. Nonperfused tubules (41 days) subjected to a 10-fold increase in bath flow rate also exhibited a threefold increase in [Ca2+]i from baseline (P < 0.001). Mechanosensitive PIEZO1 channels contribute to the flow-induced [Ca2+]i response in mouse distal tubule (Carrisoza-Gaytan R, Dalghi MG, Apodaca GL, Kleyman TR, Satlin LM. The FASEB J 33: 824.25, 2019.). Immunodetectable apical and basolateral PIEZO1 was identified in tubular structures by 21 days in culture. Basolateral PIEZO1 appeared to be functional as basolateral exposure of nonperfused tubules to the PIEZO1 activator Yoda 1 increased [Ca2+]i (P ≤ 0.001) in segments from organoids cultured for >30 days, with peak [Ca2+]i increasing with advancing days in culture. These results are consistent with a maturational increase in number and/or activity of flow/stretch-sensitive Ca2+ channels, including PIEZO1, in tubules of static organoids in culture.

Embedded 3D Printing of Architected Ceramics via Microwave-Activated Polymerization.

Light- and ink-based 3D printing methods have vastly expanded the design space and geometric complexity of architected ceramics. However, light-based methods are typically confined to a relatively narrow range of preceramic and particle-laden resins, while ink-based methods are limited in geometric complexity due to layerwise assembly. Here, embedded 3D printing is combined with microwave-activated curing to generate architected ceramics with spatially controlled composition in freeform shapes. Aqueous colloidal inks are printed within a support matrix, rapidly cured via microwave-activated polymerization, and subsequently dried and sintered into dense architectures composed of one or more oxide materials. This integrated manufacturing method opens new avenues for the design and fabrication of complex ceramic architectures with programmed composition, density, and form for myriad applications.