Ca2+-independent ZmCPK2 is inhibited by Ca2+-dependent ZmCPK17 during drought response in maize.

Calcium oscillations are induced by different stresses. Calcium-dependent protein kinases (CDPKs/CPKs) are one major group of the plant calcium decoders that are involved in various processes including drought response. Some CPKs are calcium-independent. Here, we identified ZmCPK2 as a negative regulator of drought resistance by screening an overexpression transgenic maize pool. We found that ZmCPK2 does not bind calcium, and its activity is mainly inhibited during short term abscisic acid (ABA) treatment, and dynamically changed in prolonged treatment. Interestingly, ZmCPK2 interacts with and is inhibited by calcium-dependent ZmCPK17, a positive regulator of drought resistance, which is activated by ABA. ZmCPK17 could prevent the nuclear localization of ZmCPK2 through phosphorylation of ZmCPK2T60. ZmCPK2 interacts with and phosphorylates and activates ZmYAB15, a negative transcriptional factor for drought resistance. Our results suggest that drought stress-induced Ca2+ can be decoded directly by ZmCPK17 that inhibits ZmCPK2, thereby promoting plant adaptation to water deficit.

Screening Therapeutic Effects of MSC-EVs to Acute Lung Injury Model on A Chip.

Acute lung injury (ALI) is a lethal disease with high mortality rate, and its physiologically relevant models that could mimic human disease processes are urgently needed to study pathophysiology and predict drug efficacy. Here, this work presents a novel lipopolysaccharide (LPS) based ALI model on a microfluidic chip that reconstitutes an air-liquid interface lined by human alveolar epithelium and microvascular endothelium for screening the therapeutic effects of mesenchymal stem cells (MSC) derived extracellular vesicles (MSC-EVs) to the biomimetic ALI. The air-liquid interface is established by coculture of alveolar epithelium and microvascular endothelium on the opposite sides of the porous membrane. The functionalized architecture is characterized by integrate cell layers and suitable permeability. Using this biomimetic microsystem, LPS based ALI model is established, which exhibits the disrupted alveolar-capillary barrier, reduced transepithelial/transendothelial electrical resistance (TEER), and impaired expression of junction proteins. As a reliable disease model, this work examines the effects of MSC-EVs, and the data indicate the therapeutic potential of EVs for severe ALI. MSC-EVs can alleviate barrier disruption by restoring both the epithelial and endothelial barrier integrity. They hope this study can become a unique approach to study human pathophysiology of ALI and advance drug development.

Microfluidic Encapsulation of Exosomes Derived from Lipopolysaccharide-Treated Mesenchymal Stem Cells in Hyaluronic Acid Methacryloyl to Restore Ovarian Function in Mice.

Premature ovarian failure (POF) features an upward incidence nowadays, and the human umbilical cord mesenchymal stem cells (hUC-MSCs)-derived exosomes (MSC-Exos) have shown applied values in the recovery of ovarian function. Here, a novel exosome-encapsulated microcarrier prepared by microfluidic technology for ovarian repair after chemotherapy damage is presented. The exosomes derived from lipopolysaccharide (LPS)-preconditioned hUC-MSCs are encapsulated with hyaluronic acid methacryloyl (HAMA) via microfluidic electrospray, which is named HAMA/MSC-Exos. Attributing to the biocompatibility and semipermeable property of HAMA, the encapsulated exosomes show great viability and controllable release behavior from HAMA. It is demonstrated that in situ transplantation of HAMA/MSC-Exos can rescue ovarian functions of cyclophosphamide-induced ovarian failure in mice by increasing ovarian volume, improving the number of antral follicles and restoring fertility. It is believed that the transplantation of HAMA/MSC-Exos will provide a new concept for the treatment of POF in clinical practice.

Biomimetic Alveoli System with Vivid Mechanical Response and Cell-Cell Interface.

Alveolar microenvironmental models are important for studying the basic biology of the alveolus, therapeutic trials, and drug testing. However, a few systems can fully reproduce the in vivo alveolar microenvironment including dynamic stretching and the cell-cell interface. Here, a novel biomimetic alveolus-on-a-chip microsystem is presented suitable for visualizing physiological breathing for simulating the 3D architecture and function of human pulmonary alveoli. This biomimetic microsystem contains an inverse opal structured polyurethane membrane that achieves real-time observation of mechanical stretching. In this microsystem, the alveolar-capillary barrier is created by alveolar type 2 (ATII) cells cocultured with vascular endothelial cells (ECs) on this membrane. Based on this microsystem, the phenomena of flattening and the tendency of differentiation in ATII cells are observed. The synergistic effects of mechanical stretching and ECs on the proliferation of ATII cells are also observed during the repair process following lung injury. These features indicate the potential of this novel biomimetic microsystem for exploring the mechanisms of lung diseases, which can provide future guidance concerning drug targets for clinical therapies.

Sensors-integrated organ-on-a-chip for biomedical applications.

As a promising new micro-physiological system, organ-on-a-chip has been widely utilized for in vitro pharmaceutical study and tissues engineering based on the three-dimensional constructions of tissues/organs and delicate replication of in vivo-like microenvironment. To better observe the biological processes, a variety of sensors have been integrated to realize in-situ, real-time, and sensitive monitoring of critical signals for organs development and disease modeling. Herein, we discuss the recent research advances made with respect to sensors-integrated organ-on-a-chip in this overall review. Firstly, we briefly explore the underlying fabrication procedures of sensors within microfluidic platforms and several classifications of sensory principles. Then, emphasis is put on the highlighted applications of different types of organ-on-a-chip incorporated with various sensors. Last but not least, perspective on the remaining challenges and future development of sensors-integrated organ-on-a-chip are presented.

Engineering placenta-like organoids containing endogenous vascular cells from human-induced pluripotent stem cells.

The placenta is an essential organ that maintains the health of both the fetus and its mother. Understanding the development of human placenta has been hindered by the limitations of existing animal models and monolayer cell cultures. Models that can recapitulate the essential aspects of human placental multicellular components and vasculature are still lacking. Herein, we presented a new strategy to establish placenta-like organoids with vascular-like structures from human-induced pluripotent stem cells in a defined three-dimensional (3D) culture system. The resulting placenta-like tissue resembles first-trimester human placental development in terms of complex placental components and secretory function. The multicellular tissue was characterized by the inclusion of trophoblasts (cytotrophoblasts, syncytiotrophoblasts, extravillous trophoblasts, and other endogenous vascular cells), which were identified by immunofluorescence, flow cytometry analyses, real-time quantitative reverse transcription polymerase chain reaction and single-cell RNA-seq. Moreover, the 3D tissue was able to secrete the placenta-specific hormone human chorionic gonadotropin ß (hCG-ß) and vascular endothelial growth factor A (VEGFA). The tissue responded to the inflammatory factor tumor necrosis factor-α (TNF-α) and VEGF receptor inhibitors. This new model system can represent the major features of placental cellular components, and function, which have not been realized in 2D monolayer cultures. The developed tissue system might open new avenues for studying normal early human placental development and its disease states.

Osthole Inhibits M1 Macrophage Polarization and Attenuates Osteolysis in a Mouse Skull Model.

Excessive bone resorption due to increased inflammatory factors is a common feature of inflammatory lytic bone diseases. This group of diseases is effectively treated with drugs. In recent years, many studies have reported that traditional Chinese medicine herbs have substantial effects on inflammation, osteoclast differentiation and maturation, and bone destruction. Herein, we investigated the effects of osthole (OST) on lipopolysaccharide- (LPS-) induced macrophage polarization, inflammatory responses, and osteolysis. In vitro, we used immunofluorescence and quantitative real-time polymerase chain reaction assays to confirm whether bone marrow-derived macrophages showed an increased expression of inflammatory factors, such as interleukin-6, iNOS, CCR7, and CD86, in the presence of LPS. However, we found that such expression was suppressed and that the M2 macrophage expression increased in the presence of OST. OST reduced LPS- and RANKL-induced intracellular reactive oxygen species production in the bone marrow-derived macrophages. Further, it potently suppressed osteoclast differentiation and osteoclast-specific gene expression by suppressing the P38/MAPK and NF-κB pathways. Consistent with the in vitro observations, OST greatly ameliorated LPS-induced bone resorption and modulated the ratio of macrophages at the site of osteolysis. Taken together, OST has great potential for use in the management of osteolytic diseases.

Engineering Human Brain Assembloids by Microfluidics.

Brain assembloids offer a highly promising strategy to model human brain development and disease, and advance potential studies in regenerative medicine, therapeutic screening, and drug discovery, while it is challenging to produce uniform brain organoids and assemble them flexibly by conventional methods. Here, a multidisciplinary engineered strategy to generate human brain assembloids with desired patterning based on microfluidic technology is presented. By encapsulating human induced pluripotent stem cells in microcapsules via microfluidic electrospray, brain region-specific organoids are efficiently formed, which are then introduced into a microfluidic chip consisting of a bottom layer with a micropillar array and a movable upper layer with a complementary microhole array. These brain organoids can settle into microholes and fuse into brain assembloids. As varied organoid microcapsules with designed 1D sequences or 2D arrays can be assembled into the vertical microholes, large coding amounts of fused brain assembloids with desired patterning can be produced. It is found that brain assembloids composed of cortical, hippocampal, and thalamic organoids can grow and function well, characterized with active neural migration and interaction. These features indicate that the suggested flexible, scalable, and controlled microfluidic systems are remarkably potential in wide applications of brain assembloids in neurological and biomedical fields.

Cortical Organoid-on-a-Chip with Physiological Hypoxia for Investigating Tanshinone IIA-Induced Neural Differentiation.

Cortical organoids represent cutting-edge models for mimic human brain development during the early and even middle stage of pregnancy, while they often fail to recreate the complex microenvironmental factors, such as physiological hypoxia. Herein, to recapitulate fetal brain development, we propose a novel cortical organoid-on-a-chip with physiological hypoxia and further explore the effects of tanshinone IIA (Tan IIA) in neural differentiation. The microfluidic chip was designed with a micropillar array for the controlled and efficient generation of cortical organoids. With low oxygen, the generated cortical organoids could recapitulate key aspects of early-gestational human brain development. Compared to organoids in normoxic culturing condition, the promoted neurogenesis, synaptogenesis and neuronal maturation were observed in the present microsystem, suggesting the significance of physiological hypoxia in cortical development. Based on this model, we have found that Chinese herbal drug Tan IIA could promote neural differentiation and maturation, indicating its potential therapeutic effects on neurodevelopmental disorders as well as congenital neuropsychiatric diseases. These results indicate that the proposed biomimetic cortical organoid-on-a-chip model with physiological hypoxia can offer a promising platform to simulate prenatal environment, explore brain development, and screen natural neuroactive components.

An empirical study of college students' reading engagement on academic achievement.

With the popularity of Internet technology, reading has developed in the direction of digitalization and mobileization. And entering the metaverse era, both the subject and object of reading may be redefined, presenting a new developmental pattern. This process brings a crisis to reading, such as the fragmentation of reading, the obstruction of reading needs, and the replacement of classical reading. However, reading is still an important way for college students to acquire new knowledge, broaden their horizons and improve their skills. The existence of reading crises inevitably affects the academic achievement of college students. Therefore, from the perspective of university management, this paper conducts regression analysis on 1,155 effective samples of colleges and universities in Anhui Province, extracts the factors that affect college students' reading engagement, and further explores the relationship between college students' reading engagement and academic achievement. The study concluded that: (1) in terms of family reading culture, students who grow up in families with good family reading culture perform better in reading engagement. The amount of family books, family reading education and family reading atmosphere all have significant positive effects on reading time and reflective reading strategies of college students. (2) In the cultivation of reading habits in colleges and universities, the course-driven mechanism and the atmosphere stimulating mechanism have a significant positive effect on students' reading time. The course-driven mechanism, resource supporting mechanism and atmosphere stimulating mechanism have a significant positive effect on the critical reading strategy of college students. (3) In terms of reading time, it is only found that the reading time spent on paper books has a significant positive effect on college students' academic achievement and professional quality. (4) In terms of reading strategies, the replicative reading strategy only has a significant positive effect on the improvement of college students' academic achievement and professional quality. The critical reading strategy has a significant positive effect on the professional quality, general ability and career planning ability of college students.

Coronary functional assessment in non-obstructive coronary artery disease: Present situation and future direction.

Non-obstructive coronary artery disease (CAD), which is defined as coronary stenosis <50%, has been increasingly recognized as an emerging entity in clinical practice. Vasomotion abnormality and coronary microvascular dysfunction are two major mechanisms contributing to the occur of angina with non-obstructive CAD. Although routine coronary functional assessment is limited due to several disadvantages, functional evaluation can help to understand the pathophysiological mechanism and/or to exclude specific etiologies. In this review, we summarized the potential mechanisms involved in ischemia with non-obstructive coronary arteries (INOCA) and myocardial infarction with non-obstructive coronary arteries (MINOCA), the two major form of non-obstructive CAD. Additionally, we reviewed currently available functional assessment indices and their use in non-obstructive CAD. Furthermore, we speculated that novel technique combined anatomic and physiologic parameters might provide more individualized therapeutic choice for patients with non-obstructive CAD.

Human Endometrium-Derived Adventitial Cell Spheroid-Loaded Antimicrobial Microneedles for Uterine Regeneration.

Asherman's syndrome (AS) occurs as a consequence of severe damage to the endometrial basalis, usually leading to menstrual abnormalities, infertility, and recurrent miscarriage in women. Currently, human endometrium-derived adventitial cells (En-ADVs) are considered ideal seed cells with high pluripotency for regenerative medicine. However, critical issues such as noninvasive repair of tissues, targeting of native stem cells, and continuous action in the injured sites are not well resolved. Herein, En-ADV spheroid-loaded hierarchical microneedles (MN/En-ADV) for in situ intrauterine repair are developed. The flexible microneedles are fabricated with gelatin methacryloyl and lactoferrin, imparting the characteristics of rapid degradation and antimicrobial activity. Benefiting from an array of microwells on microneedles, En-ADVs can rapidly form 3D cell spheroids, which display higher potential for cell proliferation, differentiation, and migration than dissociated cells. With the application of MN/En-ADV, the repaired uteri show well-defined myometrial regeneration, angiogenesis, and an increase of endometrial receptivity in a rat AS model. Notably, embryos are able to implant in the reconstructed sites and remain viable, indicating that this system promotes the restoration of both normal morphology and reproductive function in the injured uterus. It is anticipated that multifunctional MN/En-ADV can be an ideal candidate for versatile in situ tissue regeneration.

Fluidic Flow Enhances the Differentiation of Placental Trophoblast-Like 3D Tissue from hiPSCs in a Perfused Macrofluidic Device.

The human placenta serves as a multifunctional organ to maintain the proper development of a fetus. However, our knowledge of the human placenta is limited due to the lack of appropriate experimental models. In this work, we created an in vitro placental trophoblast-like model via self-organization of human induced pluripotent stem cells (hiPSCs) in a perfused 3D culture macrofluidic device. This device allowed cell seeding, in situ trophoblast lineage differentiation, and formation of trophoblast-like tissues from hiPSCs in a biomimetic microenvironment. It incorporated extracellular matrix (ECM) and fluid flow in a single device. After trophoblast lineage differentiation, we were able to generate the 3D clusters with major cell types of the human placenta, including trophoblast progenitor cytotrophoblasts (CTBs), differentiated subtypes, syncytiotrophoblasts (STBs), and extravillous trophoblasts (EVTs) under long-term 3D culture (∼23 days). Moreover, the formed tissues exhibited enhanced expressions of CTB-, STB-, and EVT-related markers at the level of genes and proteins under a dynamic culture compared with static conditions. RNA-seq analysis revealed the higher expression of trophoblast-specific genes in 3D tissues, indicating the essential role of fluid flow to promote the trophoblast differentiation of hiPSCs. The established placental 3D model combined a bioengineering strategy with developmental principles, providing a promising platform for the study of placental biology in a biomimetic microenvironment in health and disease.

Bioactive Fish Scale Scaffolds with MSCs-Loading for Skin Flap Regeneration.

Skin flap transplantations are common methods for covering and repairing tissue defects in surgery, while the survival rates of these skin flaps are still low due to the vascular crisis and necrosis. To improve this situation, herein a novel biohybrid scaffold is proposed by integrating the advantages of anisotropic fish scales and mesenchymal stem cells (MSCs) for skin flap regeneration. The fish scale scaffold is obtained through its decellularization and decalcification processes, which reserved intact collagen, glycosaminoglycan, and other endogenous growth factors for MSCs and human vascular endothelial cells proliferation. As the scaffold maintains intrinsic anisotropic structures on both surfaces, the proliferative cells can be elongated along the aligned structures on the fish scale, which endow them the capacity to differentiate into multiple directions. Based on these features, it is demonstrated from an in vivo experiment that the MSCs-loading fish scale scaffolds can effectively convert the activated inflammatory macrophages into anti-inflammatory properties, reduce the inflammation around the flap, and improve the survival rate. These results indicate that the MSCs-loading fish scale scaffold is suitable and has the potential for skin flap regeneration and functional recovery.

Fasting Blood-Glucose Level and Clinical Outcome in Anterior Circulation Ischemic Stroke of Different Age Groups After Endovascular Treatment.

Objective: We aimed to analyze the association between fasting blood-glucose (FBG) level and 3-month functional outcome in anterior circulation ischemic stroke in different age groups after endovascular treatment (EVT). Methods: We retrospectively analyzed the consecutive patients with acute ischemic stroke (AIS) receiving EVT from our department between July 2015 and March 2021. The patients were categorized into the older (≥60 years) and younger (<60 years) groups, and patients in each age group were dichotomized into favorable versus unfavorable outcomes according to the 3-month modified Rankin Scale (mRS) score. Results: A total of 504 patients (286 males and 218 females) were included in our study. Three hundred ninety-two patients (77.8%) belonged to the group aged ≥60 years, and 112 (22.2%) belonged to the group aged <60 years. At the end of the study, 222 (56.6%) patients developed unfavorable outcomes in the older group and 31 (27.7%) showed unfavorable outcomes in the younger group. FBG level of the younger patients was significantly lower than that of older patients. In the older group, FBG level independently predicted a 3-month clinical unfavorable outcome with an odds ratio of 1.242 (95% confidence interval, 1.096-1.407; p = 0.001). However, the association was not found in the younger group (p = 0.376). Conclusion: Higher FBG level is an independent risk factor for 3-month unfavorable outcome in the AIS patients aged ≥60 years receiving EVT, but no similar effect was seen in the group aged <60 years.

A Biomimetic Human Lung-on-a-Chip with Colorful Display of Microphysiological Breath.

Lung-on-a-chip models hold great promise for disease modeling and drug screening. Herein, inspired by the iridescence phenomenon of soap bubbles, a novel biomimetic 3D microphysiological lung-on-a-chip system with breathing visualization is presented. The system, with an array of pulmonary alveoli at the physiological scale, is constructed and coated with structural color materials. Cyclic deformation is induced by regular airflow, resembling the expansion and contraction of the alveoli during rhythmic breathing. As the deformation is accompanied with corresponding synchronous shifts in the structural color, the constructed system offers self-reporting of the cell mechanics and enables real-time monitoring of the cultivation process. Using this system, the dynamic relationships between the color atlas and disease symptoms, showing the essential role of mechanical stretching in the phenotypes of idiopathic pulmonary fibrosis, are investigated. These features make this human lung system ideal in biological study, disease monitoring, and drug discovery.

Establishment of Trophoblast-Like Tissue Model from Human Pluripotent Stem Cells in Three-Dimensional Culture System.

The placenta has a lifelong impact on the health of both the mother and fetus. Despite its significance, human early placental development is poorly understood due to the limited models. The models that can reflect the key features of early human placental development, especially at early gestation, are still lacking. Here, the authors report the generation of trophoblast-like tissue model from human pluripotent stem cells (hPSCs) in three-dimensional (3D) cultures. hPSCs efficiently self-organize into blastocoel-like cavities under defined conditions, which produce different trophoblast subtypes, including cytotrophoblasts (CTBs), syncytiotrophoblasts (STBs), and invasive extravillous trophoblasts (EVTs). The 3D cultures can exhibit microvilli structure and secrete human placenta-specific hormone. Single-cell RNA sequencing analysis further identifies the presence of major cell types of trophoblast-like tissue as existing in vivo. The results reveal the feasibility to establish 3D trophoblast-like tissue model from hPSCs in vitro, which is not obtained by monolayer culture. This new model system can not only facilitate to dissect the underlying mechanisms of early human placental development, but also imply its potential for study in developmental biology and gestational disorders.

HiPSC-derived multi-organoids-on-chip system for safety assessment of antidepressant drugs.

The poor predictive power of existing preclinical models has spurred efforts to develop human-relevant models for accurate assessment of drug safety. In this work, we developed a multi-organoids-on-a-chip system derived from human induced pluripotent stem cells (hiPSCs), which allows for the assessment of the cardiac safety of an antidepressant drug, following liver metabolism in vitro. This liver-heart organoids-on-chip device contains compartmentalized chambers separated by a porous membrane, which permits the co-culture of 3D human liver organoids in the upper multi-well chamber and cardiac organoids in the bottom micropillar array simultaneously. The co-cultured liver and heart organoids on chip maintained good viability and human organ-specific functions respectively, including the synthesis of albumin and urea of liver organoids, and the beating function of cardiac organoids. In particular, the liver organoids displayed proper metabolic capabilities with high expression of CYP450 enzyme genes. Clomipramine, a widely used antidepressant drug, can be metabolized into an active metabolite (desmethylclomipramine) through the hepatic CYP450 enzymes of liver organoids on chip identified by mass spectrometry. After exposure to 1 µM clomipramine in the liver chamber for 24 h and 48 h, the co-cultured heart organoids in the bottom layer showed significantly reduced cell viability, impaired functions of cardiac beating and calcium flux, indicating the hepatic metabolism-dependent cardiotoxicity induced by clomipramine. By combining stem cell biology and microengineered technology, this proposed hiPSC-derived multi-organoids-on-a-chip system can reflect human organ-specific functions, as well as the complex process of drug metabolism and responses at the multi-organ level. It may provide a novel platform for the assessment of drug effectiveness and safety in vitro.