The Chinese pine genome and methylome unveil key features of conifer evolution.

Conifers dominate the world's forest ecosystems and are the most widely planted tree species. Their giant and complex genomes present great challenges for assembling a complete reference genome for evolutionary and genomic studies. We present a 25.4-Gb chromosome-level assembly of Chinese pine (Pinus tabuliformis) and revealed that its genome size is mostly attributable to huge intergenic regions and long introns with high transposable element (TE) content. Large genes with long introns exhibited higher expressions levels. Despite a lack of recent whole-genome duplication, 91.2% of genes were duplicated through dispersed duplication, and expanded gene families are mainly related to stress responses, which may underpin conifers' adaptation, particularly in cold and/or arid conditions. The reproductive regulation network is distinct compared with angiosperms. Slow removal of TEs with high-level methylation may have contributed to genomic expansion. This study provides insights into conifer evolution and resources for advancing research on conifer adaptation and development.

Flexible liquid-diode microtubes from multimodal microfluidics.

Directional transport of liquids is of great importance in energy saving, chemical/biomedical engineering, and microfluidics applications. Despite considerable progress in engineering different open surfaces to achieve liquid manipulation, the realization of diode-like liquid transport in enclosed spaces is still challenging. Here, a flexible diode microtube is presented for directional liquid transport within confined spaces using pulsed microfluidics. The microtubes exhibit sophisticated microstructures on the inner wall, replicated from a precisely controlled flow configuration in the microfluidic channel. Under the effect of asymmetric pinning and unbalanced Laplace pressure, such microtubes enable directional liquid transport in closed channels. More importantly, by integrating in situ flow lithography with the microfluidic system, segmented liquid diodes are fabricated as assembly units for the construction of fluidic-electronic circuits that perform logic operations. These results demonstrate the capacity of the present liquid-diode microtubes for flexible, directional, and programmable liquid transport. We believe that it can open an avenue for designing advanced fluidic circuit-based devices toward versatile practical applications.

CD5 Binds to Interleukin-6 and Induces a Feed-Forward Loop with the Transcription Factor STAT3 in B Cells to Promote Cancer.

The participation of a specific subset of B cells and how they are regulated in cancer is unclear. Here, we demonstrate that the proportion of CD5(+) relative to interleukin-6 receptor α (IL-6Rα)-expressing B cells was greatly increased in tumors. CD5(+) B cells responded to IL-6 in the absence of IL-6Rα. IL-6 directly bound to CD5, leading to activation of the transcription factor STAT3 via gp130 and its downstream kinase JAK2. STAT3 upregulated CD5 expression, thereby forming a feed-forward loop in the B cells. In mouse tumor models, CD5(+) but not CD5(-) B cells promoted tumor growth. CD5(+) B cells also showed activation of STAT3 in multiple types of human tumor tissues. Thus, our findings demonstrate a critical role of CD5(+) B cells in promoting cancer.

Stem cell recruitment polypeptide hydrogel microcarriers with exosome delivery for osteoarthritis treatment.

With the accelerated aging tendency, osteoarthritis (OA) has become an intractable global public health challenge. Stem cells and their derivative exosome (Exo) have shown great potential in OA treatment. Research in this area tends to develop functional microcarriers for stem cell and Exo delivery to improve the therapeutic effect. Herein, we develop a novel system of Exo-encapsulated stem cell-recruitment hydrogel microcarriers from liquid nitrogen-assisted microfluidic electrospray for OA treatment. Benefited from the advanced droplet generation capability of microfluidics and mild cryogelation procedure, the resultant particles show uniform size dispersion and excellent biocompatibility. Moreover, acryloylated stem cell recruitment peptides SKPPGTSS are directly crosslinked within the particles by ultraviolet irradiation, thus simplifying the peptide coupling process and preventing its premature release. The SKPPGTSS-modified particles can recruit endogenous stem cells to promote cartilage repair and the released Exo from the particles further enhances the cartilage repair performance through synergistic effects. These features suggest that the proposed hydrogel microcarrier delivery system is a promising candidate for OA treatment.

Light environment affects the efficiency of surgical suture training.

BACKGROUND: Suture knotting is the basis of surgical skills. In the process of surgical skills learning, the surrounding environment, especially the light, will affect the efficiency of learning. This study investigated the effect of optical environment on the learning of stitching and knotting skills. METHODS: A total of 44 medical students were randomly divided into four groups and participated in the study of suture knotting in four different optical environments. During the process, we assess objective pressure level by testing salivary amylase activity Likert scale and objective structured clinical examination (OSCE) was used to estimate the subjective psychological state and overall skill mastery in surgical suturing respectively. RESULTS: Under high illumination conditions (700 lx), the salivary amylase activity of the high color temperature group (6000 K) was significantly higher than that of the low color temperature group (4000 K) (p < 0.0001). Similarly, under low illumination (300 lx), the salivary amylase activity of the high color temperature group was also significantly higher than that of the low color temperature group (p < 0.05). The student under high illumination conditions (700 lx) and the low color temperature (6000 K) have an autonomy score between 37-45, which is significantly higher compared to the other three groups (p < 0.0001). Group 2 has an average OSCE score of 95.09, which were significantly higher than those of the other three groups (p < 0.05). CONCLUSION: High illumination combined with low color temperature is considered as the optimal training conditions, promoting trainees' optimism, reducing stress levels, and enhancing learning efficiency. These results highlight the pivotal role of light environment in improving the quality and efficiency of surgical skills training.

The Nrf2/HMGB1/NF-κB axis modulates chondrocyte apoptosis and extracellular matrix degradation in osteoarthritis.

Osteoarthritis (OA) is a degenerative or posttraumatic condition of the joints. In OA chondrocytes, Nrf2 functions as a stress response regulator with antioxidant and anti-inflammatory effects. This study aims to investigate the role of Nrf2 and its downstream pathway in the development of osteoarthritis. IL-1ß treatment suppresses Nrf2, aggrecan, and COL2A1 levels and cell viability but promotes apoptosis in chondrocytes. IL-1ß stimulation induces cell apoptosis, upregulates the mRNA expression of inflammatory factors, decreases aggrecan, COL2A1, and Bcl-2 levels but increases ADAMTS-5, ADAMTS-4, MMP13, cleaved caspase 3, and BAX levels, and promotes p65 phosphorylation. Nrf2 overexpression exerts opposite effects on IL-1ß-treated chondrocytes, as demonstrated by the significant attenuation of IL-1ß-induced changes in chondrocytes. By binding to the HMGB1 promoter region, Nrf2 suppresses HMGB1 expression. Similar to Nrf2 overexpression, HMGB1 knockdown also attenuates IL-1ß-induced changes in chondrocytes. Notably, under IL-1ß stimulation, the effects of Nrf2 overexpression or tert-butylhydroquinone (TBHQ, an activator of Nrf2) on apoptosis, inflammatory factor expression, ECM and apoptosis, and NF-κB pathway activity in chondrocytes are remarkably reversed by HMGB1 overexpression or recombinant HMGB1 (rHMGB1). Similarly, rHMGB1 could partially counteract the curative effect of TBHQ on OA damage in mice. In OA cartilage tissue samples, the level of Nrf2 is lower, while the levels of HMGB1, apoptotic, and inflammatory factors are increased compared to normal cartilage tissue samples. In conclusion, for the first time, the Nrf2/HMGB1 axis was found to modulate apoptosis, ECM degradation, inflammation and activation of NF-κB signaling in chondrocytes and OA mice.

Characteristics and Application of a Novel Cold-Adapted and Salt-Tolerant Protease EK4-1 Produced by an Arctic Bacterium Mesonia algae K4-1.

Mesonia algae K4-1 from the Arctic secretes a novel cold-adapted and salt-tolerant protease EK4-1. It has the highest sequence similarity with Stearolysin, an M4 family protease from Geobacillus stearothermophilus, with only 45% sequence identity, and is a novel M4 family protease. Ek4-1 has a low optimal catalytic temperature (40 °C) and is stable at low temperatures. Moreover, EK4-1 is still active in 4 mol/L NaCl solution and is tolerant to surfactants, oxidizing agents and organic solvents; furthermore, it prefers the hydrolysis of peptide bonds at the P1' position as the hydrophobic residues, such as Leu, Phe and Val, and amino acids with a long side chain, such as Phe and Tyr. Mn2+and Mg2+ significantly promoted enzyme activity, while Fe3+, Co+, Zn2+ and Cu2+ significantly inhibited enzyme activity. Amino acid composition analysis showed that EK4-1 had more small-side-chain amino acids and fewer large-side-chain amino acids. Compared with a thermophilic protease Stearolysin, the cold-adapted protease EK4-1 contains more random coils (48.07%) and a larger active pocket (727.42 Å3). In addition, the acidic amino acid content of protease EK4-1 was higher than that of the basic amino acid, which might be related to the salt tolerance of protease. Compared with the homologous proteases EB62 and E423, the cold-adapted protease EK4-1 was more efficient in the proteolysis of grass carp skin, salmon skin and casein at a low temperature, and produced a large number of antioxidant peptides, with DPPH, ·OH and ROO· scavenging activities. Therefore, cold-adapted and salt-tolerant protease EK4-1 offers wide application prospects in the cosmetic and detergent industries.

A retrospective study of end-stage kidney disease patients on maintenance hemodialysis with renal osteodystrophy-associated fragility fractures.

BACKGROUND: Nephropathy associated metabolic disorder induces high incidence of fragility fracture in end-stage renal disease (ESRD) patients. As the risk factors and prognosis of fragility fracture in ESRD patients are unclear, more research is needed. This study aimed to evaluate various risk factors for ESRD-related fragility fractures, explore factors affecting the prognosis of patients with such fractures, and provide information for prevention and treatment of renal osteopathy to improve the prognosis of patients. METHODS: In this retrospective case-control study, the case notes of 521 ESRD patients who received maintenance dialysis for at least 3 months were examined. Finally, 44 patients diagnosed with fragility fractures were assigned to the fragility fracture (FF) group and 192 patients were included in the control group (CG). Demographic information, underlying diseases, nutritional, bone metabolism, and renal function parameters, along with the number and causes of any deaths, were recorded for multiple statistical analysis. RESULTS: The FF group had increased incidences of essential hypertension and diabetes mellitus and higher serum calcium, corrected calcium, alkaline phosphatase, and hemoglobin levels. Immunoreactive parathyroid hormone (iPTH), total cholesterol (TC), and low density lipoprotein (LDL) levels were higher in the CG. Multivariate Cox regression analysis revealed that fragility fracture was an independent risk factor for all-cause mortality in ESRD patients (P < .001, RR: 4.877, 95% CI: 2.367-10.013). CONCLUSIONS: Essential hypertension and diabetes, high serum calcium and alkaline phosphatase levels, and reduced iPTH levels were risk factors for fragility fracture in ESRD patients. Maintaining iPTH and serum TC levels may protect against fragility fractures in them. Fragility fractures may yield poor prognosis and shorter lifespan. The presence of fragility fracture was an independent predictor of all-cause death in ESRD patients.

Sal-like 4 protein levels in breast cancer cells are post-translationally down-regulated by tripartite motif-containing 21.

Sal-like 4 (SALL4) is a transcription factor that enhances proliferation and migration in breast cancer cells. SALL4 expression therefore has the potential to promote cancer malignancy. However, the regulatory mechanisms involved in SALL4 protein expression have not been thoroughly elucidated. In this study, we observed that treating MCF-7 and SUM159 breast cancer cell lines with a proteasome inhibitor increases SALL4 protein levels, suggesting that SALL4 is degraded by the ubiquitin-proteasome system. Using immunoprecipitation to uncover SALL4-binding proteins, we identified an E3 ubiquitin-protein ligase, tripartite motif-containing 21 (TRIM21). Using an EGFP reporter probe of the major SALL4 isoform SALL4B, we observed that shRNA-mediated knockdown of TRIM21 increases cellular SALL4B levels. Immunostaining experiments revealed that TRIM21 localizes to the nucleus, and a K64R substitution in the nuclear localization motif in SALL4B increased SALL4B levels in the cytoplasm. These results suggested that TRIM21 is involved in nuclear SALL4 degradation. To identify the amino acid residue that is targeted by TRIM21, we fragmented the SALL4B sequence, fused it to EGFP, and identified Lys-190 in SALL4B as TRIM21's target residue. Amino acid sequence alignments of SALL family members indicated that the region around SALL4 Lys-190 is conserved in both SALL1 and SALL3. Because SALL1 and SALL4 have similar functions, we constructed a SALL1-EGFP probe and found that the TRIM21 knockdown increases SALL1 levels, indicating that TRIM21 degrades both SALL1 and SALL4. Our findings extend our understanding of SALL4 and SALL1 regulation and may contribute to the development of SALL4-targeting therapies.

The Sal-like 4 - integrin α6ß1 network promotes cell migration for metastasis via activation of focal adhesion dynamics in basal-like breast cancer cells.

During metastasis, cancer cell migration is enhanced. However, the mechanisms underlying this process remain elusive. Here, we addressed this issue by functionally analyzing the transcription factor Sal-like 4 (SALL4) in basal-like breast cancer cells. Loss-of-function studies of SALL4 showed that this transcription factor is required for the spindle-shaped morphology and the enhanced migration of cancer cells. SALL4 also up-regulated integrin gene expression. The impaired cell migration observed in SALL4 knockdown cells was restored by overexpression of integrin α6 and ß1. In addition, we clarified that integrin α6 and ß1 formed a heterodimer. At the molecular level, loss of the SALL4 - integrin α6ß1 network lost focal adhesion dynamics, which impairs cell migration. Over-activation of Rho is known to inhibit focal adhesion dynamics. We observed that SALL4 knockdown cells exhibited over-activation of Rho. Aberrant Rho activation was suppressed by integrin α6ß1 expression, and pharmacological inhibition of Rho activity restored cell migration in SALL4 knockdown cells. These results indicated that the SALL4 - integrin α6ß1 network promotes cell migration via modulation of Rho activity. Moreover, our zebrafish metastasis assays demonstrated that this gene network enhances cell migration in vivo. Our findings identify a potential new therapeutic target for the prevention of metastasis, and provide an improved understanding of cancer cell migration.

[Suppression of miR-30a/HMGA2-mediated autophagy in osteosarcoma cells impacts chemotherapeutics-induced apoptosis].

OBJECTIVE: To investigate the effect of miR-30a/HMGA2-mediated autophagy in osteosarcoma cells on apoptosis induced by chemotherapeutics. 
 Methods: A total of 30 osteosarcoma tissues of sensitive and resistant to chemotherapeutics were divided into a chemotherapy-sensitive group and a chemotherapy-resistant group. The mRNA expression levels of miR-30a and high mobility group protein A2 (HMGA2) in the chemotherapy-sensitive group and the chemotherapy-resistant group, and the mRNA expression levels of miR-30a in osteosarcoma U2-OS cells treated by cisplatin, doxorubicin and methotrexate at different concentrations were detected by real-time PCR. The expression levels of autophagy related protein Beclin 1, microtubule associated protein 1 light chain 3B (LC3B) and autophagy factor P62 were detected by Western blotting. The osteosarcoma U2-OS cells were transfected with miR-30a mimics and miR-30a inhibitors to construct a miR-30a high expression group, a miR-30a low expression group and a control group. The expression levels of Beclin 1, LC3B and P62 in osteosarcoma U2-OS cells after treatment of cisplatin and doxorubicin in these 3 groups were detected by Western blotting; the level of autophagy was detected by monodansylcada (MDC) staining; the level of ROS was detected by dihydroethidium (DHE); the level of cell surviving rate was detected by cell counting kit-8 (CCK-8); the level of apoptosis was detected by annexin APC/PI double staining; the level of mitochondria oxidative damage was detected by mitochondrial membrane potential assay kit with JC-1 (JC-1 method). The interaction between miR-30a and HMGA2 was detected by dual luciferase reporter assay. The osteosarcoma U2-OS cells were transfected with HMGA2 mimics and HMGA2-shRNA to construct a high HMGA2 group, a low HMGA2 group, and a control group. The expression levels of Beclin 1, LC3B and P62 in osteosarcoma U2-OS cells after the treatment of cisplatin were detected by Western blotting.
 Results: The level of miR-30a in the chemotherapy-resistant tissues was significantly lower than that in the chemotherapy-sensitive tissues (P<0.05), and the expression of HMGA2 was opposite comparing to that of miR-30a (P<0.05). After the treatment by low concentration (5 µmol/L) of chemotherapeutics, the level of miR-30a was down-regulated in osteosarcoma U2-OS cells, accompanied with up-regulation of Beclin 1 and LC3B (P<0.01) and down-regulation of P62 (P<0.01). Compared with the control group, the expression levels of Beclin 1 and LC3B were significantly decreased (P<0.05), and the expression level of P62 was significantly increased (P<0.05) in the miR-30a high expression group, which was opposite in the miR-30a low expression group. In the miR-30a high expression group treated by chemotherapeutics, the level of autophagy and the cell survival rate were lower than those in group with low expression of miR-30a, while the levels of ROS, the mitochondrial oxidative damage and the apoptosis were higher than those in group with low expression of miR-30a (all P<0.05). The targeting interaction between HMGA2 and miR-30a were verified by dual luciferase reporter assay. Compared with the control group, the expression levels of Beclin 1 and LC3B were significantly increased (P<0.05), and the expression level of P62 was significantly decreased (P<0.05) in the HMGA2 high expression group, which was opposite in the HMGA2 low expression group.
 Conclusion: Suppression of miR-30a/HMGA2-mediated autophagy in osteosarcoma cells is likely to enhance the therapeutic effect of chemotherapeutics.

Ultrasonic detection based on polarization-dependent optical reflection.

Owing to their extremely wide bandwidths, pure optical ultrasonic detection methods are gaining increasing interest. In this Letter, we proposed a simple ultrasonic detector that is based on the polarization-dependent optical reflection. When the acoustic wave reaches the liquid-glass interface, the acoustic pressure changed the relative refractive index between two media, leading to perturbations in the reflectance of the optical probe beam in glass. Unlike previous studies that detected the modulations in the intensity of the reflected beam, our method, named "polarization-dependent reflection ultrasonic detection (PRUD)," detects the intensity difference between two polarization components of the same probe beam. The PRUD significantly increased the sensitivity. Besides a phantom study, we also successfully detect weak photoacoustic waves in an in vivo animal experiment. This novel method can provide a simple way for ultrasonic detection, which will have great potential for ultrasound and photoacoustic imaging and sensing.

A homeobox protein, NKX6.1, up-regulates interleukin-6 expression for cell growth in basal-like breast cancer cells.

Among breast cancer subtypes, basal-like breast cancer is particularly aggressive, and research on the molecules involved in its pathology might contribute to therapy. In this study, we found that expression of NKX6.1, a homeobox transcription factor, is higher in basal-like breast cancer than in other subtypes. In loss-of-function experiments on basal-like breast cancer cell lines, NKX6.1-depleted cells exhibited reduced cell growth. Because cytokine interleukin-6 (IL-6) is expressed in basal-like breast cancer, and increases cell growth, we analyzed expression levels of IL6, an IL-6 gene, and observed reduced IL6 expression in NKX6.1-depleted cells. In a reporter assay, IL6 promoter activity was reduced by loss of NKX6.1 function. A pull-down assay showed that NKX6.1 binds to the proximal region in IL6 promoter. These results indicate that NKX6.1 directly up-regulates IL6 expression. To investigate further, we established cells with forced expression of IL-6. We observed that exogenous IL-6 expression restored the reduced cell growth of NKX6.1-depleted cells. Furthermore, orthotopic xenografts showed that NKX6.1-depleted cells lost the capacity for tumor formation. We therefore conclude that NKX6.1 is a factor for IL-6-regulated growth and tumor formation in basal-like breast cancer. Our findings facilitate profound understanding of basal-like breast cancer, and the development of suitable therapy.

CD8+ T-cell immunosurveillance constrains lymphoid premetastatic myeloid cell accumulation.

Increasing evidence suggests that premetastatic niches, consisting mainly of myeloid cells, provide microenvironment critical for cancer cell recruitment and survival to facilitate metastasis. While CD8(+) T cells exert immunosurveillance in primary human tumors, whether they can exert similar effects on myeloid cells in the premetastatic environment is unknown. Here, we show that CD8(+) T cells are capable of constraining premetastatic myeloid cell accumulation by inducing myeloid cell apoptosis in C57BL/6 mice. Ag-specific CD8(+) T-cell cytotoxicity against myeloid cells in premetastatic lymph nodes is compromised by Stat3. We demonstrate here that Stat3 ablation in myeloid cells leads to CD8(+) T-cell activation and increased levels of IFN-γ and granzyme B in the premetastatic environment. Furthermore, Stat3 negatively regulates soluble Ag cross-presentation by myeloid cells to CD8(+) T cells in the premetastatic niche. Importantly, in tumor-free lymph nodes of melanoma patients, infiltration of activated CD8(+) T cells inversely correlates with STAT3 activity, which is associated with a decrease in number of myeloid cells. Our study suggested a novel role for CD8(+) T cells in constraining myeloid cell activity through direct killing in the premetastatic environment, and the therapeutic potential by targeting Stat3 in myeloid cells to improve CD8(+) T-cell immunosurveillance against metastasis.

Slip-ring-based multi-transducer photoacoustic tomography system.

Although the transducer array-based photoacoustic tomography (PAT) system provides fast imaging speed, its high cost and system complexity hinder its implementations. In this Letter, for the first time, to the best of our knowledge, the electrical slip ring was used to develop a PAT system that compromises the cost and the imaging speed. This system enables using multiple transducers to image the target simultaneously and continuously. In addition, it is versatile to use different transducers. The performance of this PAT system has been demonstrated by both phantom and in vivo animal experiments.

An osteopontin-integrin interaction plays a critical role in directing adipogenesis and osteogenesis by mesenchymal stem cells.

An imbalance between normal adipogenesis and osteogenesis by mesenchymal stem cells (MSCs) has been shown to be related to various human metabolic diseases, such as obesity and osteoporosis; however, the underlying mechanisms remain elusive. We found that the interaction between osteopontin (OPN), an arginine-glycine-aspartate-containing glycoprotein, and integrin αv/ß1 plays a critical role in the lineage determination of MSCs. Although OPN is a well-established marker during osteogenesis, its role in MSC differentiation is still unknown. Our study reveals that blockade of OPN function promoted robust adipogenic differentiation, while inhibiting osteogenic differentiation. Re-expression of OPN restored a normal balance between adipogenesis and osteogenesis in OPN(-/-) MSCs. Retarded bone formation by OPN(-/-) MSCs was also verified by in vivo implantation with hydroxyapatite-tricalcium phosphate, a bone-forming matrix. The role of extracellular OPN in MSC differentiation was further demonstrated by supplementation and neutralization of OPN. Blocking well-known OPN receptors integrin αv/ß1 but not CD44 also affected MSC differentiation. Further studies revealed that OPN inhibits the C/EBPs signaling pathway through integrin αv/ß1. Consistent with these in vitro results, OPN(-/-) mice had a higher fat to total body weight ratio than did wild-type mice. Therefore, our study demonstrates a novel role for OPN-integrin αv/ß1 in regulating MSC differentiation.

Magnetic Polysaccharide Mesenchymal Stem Cells Exosomes Delivery Microcarriers for Synergistic Therapy of Osteoarthritis.

Osteoarthritis (OA) is a prevalent degenerative disease that afflicts more than 250 million people worldwide, impairing their mobility and quality of life. However, conventional drug therapy is palliative. Exosomes (Exo), although with the potential to fundamentally repair cartilage, face challenges in their efficient enrichment and delivery. In this study, we developed magnetic polysaccharide hydrogel particles as microcarriers for synergistic therapy of OA. The microcarriers were composed of modified natural polysaccharides, hyaluronic acid (HAMA), and chondroitin sulfate (CSMA), and were generated from microfluidic electrospray in combination with a cryogelation process. Magnetic nanoparticles with spiny structures capable of capturing stem cell Exo were encapsulated within the microcarriers together with an anti-inflammatory drug diclofenac sodium (DS). The released DS and Exo from the microcarriers had a synergistic effect in alleviating the OA symptoms and promoting cartilage repair. The in vitro and in vivo results demonstrated the excellent performance of the microcarrier for OA treatment. We believe this work has potential for Exo therapy of OA and other related diseases.

CHRDL2 activates the PI3K/AKT pathway to ameliorate glucocorticoid-induced damages to bone microvascular endothelial cells (BMECs).

Steroid-induced avascular necrosis of the femoral head (ANFH) is characterized by the death of bone tissues, leading to the impairment of normal reparative processes within micro-fractures in the femoral head. Glucocorticoid (GCs)-induced bone microvascular endothelial cell (BMEC) damage has been reported to contribute to ANFH development. In this study, differentially expressed genes (DEGs) between necrosis of the femoral head (NFH) and normal samples were analyzed based on two sets of online expression profiles, GSE74089 and GSE26316. Chordin-like 2 (CHRDL2) was found to be dramatically downregulated in NFH samples. In GCs-stimulated BMECs, cellular damages were observed alongside CHRDL2 down-regulation. GCs-caused cell viability suppression, cell apoptosis promotion, tubule formation suppression, and cell migration suppression were partially abolished by CHRDL2 overexpression but amplified by CHRDL2 knockdown; consistent trends were observed in GCs-caused alterations in the protein levels of VEGFA, VEGFR2, and BMP-9 levels, and the ratios of Bax/Bcl-2 and cleaved-caspase3/Caspase3. GC stimulation significantly inhibited PI3K and Akt phosphorylation in BMECs, whereas the inhibitor effects of GCs on PI3K and Akt phosphorylation were partially attenuated by CHRDL2 overexpression but further amplified by CHRDL2 knockdown. Moreover, CHRDL2 overexpression caused improvement in GCs-induced damages to BMECs that were partially eliminated by PI3K inhibitor LY294002. In conclusion, CHRDL2 is down-regulated in NFH samples and GCs-stimulated BMECs. CHRDL2 overexpression could improve GCs-caused BMEC apoptosis and dysfunctions, possibly via the PI3K/Akt pathway.

Real-time dual-modal photoacoustic and fluorescence small animal imaging.

By combining optical absorption contrast and acoustic resolution, photoacoustic imaging (PAI) has broken the barrier in depth for high-resolution optical imaging. Meanwhile, Fluorescence imaging (FLI), owing to advantages of high sensitivity and high specificity with abundant fluorescence agents and proteins, has always been playing a key role in live animal studies. Based on different optical contrast mechanisms, PAI and FLI can provide important complementary information to each other. In this work, we uniquely designed a Photoacoustic-Fluorescence (PA-FL) imaging system that provides real-time dual modality imaging, in which a half-ring ultrasonic array is employed for high quality PA tomography and a specially designed optical window allows simultaneous whole-body fluorescence imaging. The performance of this dual modality system was demonstrated in live animal studies, including real-time monitoring of perfusion and metabolic processes of fluorescent dyes. Our study indicates that the PA-FL imaging system has unique potential for live small animal research.

Biomimetic Tertiary Lymphoid Structures with Microporous Annealed Particle Scaffolds for Cancer Postoperative Therapy.

Immunotherapy plays a vital role in cancer postoperative treatment. Strategies to increase the variety of immune cells and their sustainable supply are essential to improve the therapeutic effect of immune cell-based immunotherapy. Here, inspired by tertiary lymphoid structures (TLSs), we present a microfluidic-assisted microporous annealed particle (MAP) scaffold for the persistent recruitment of diverse immune cells for cancer postoperative therapy. Based on the thermochemical responsivity of gelatin methacryloyl (GelMA), the MAP scaffold was fabricated by physical cross-linking and sequential photo-cross-linking of GelMA droplets, which were prepared by microfluidic electrospraying. Due to the encapsulation of liquid nitrogen-inactivated tumor cells and immunostimulant, the generated MAP scaffold could recruit a large number of immune cells, involving T cells, macrophages, dendritic cells, B cells, and natural killer cells, thereby forming the biomimetic TLSs in vivo. In addition, by combination of immune checkpoint inhibitors, a synergistic anticancer immune response was provoked to inhibit tumor recurrence and metastasis. These properties make the proposed MAP scaffold-based artificial TLSs of great value for efficient cancer postoperative therapy.