YUCCA2 (YUC2)-Mediated 3-Indoleacetic Acid (IAA) Biosynthesis Regulates Chloroplast RNA Editing by Relieving the Auxin Response Factor 1 (ARF1)-Dependent Inhibition of Editing Factors in Arabidopsis thaliana.

Although recent research progress on the abundant C-to-U RNA editing events in plant chloroplasts and mitochondria has uncovered many recognition factors and their molecular mechanisms, the intrinsic regulation of RNA editing within plants remains largely unknown. This study aimed to establish a regulatory relationship in Arabidopsis between the plant hormone auxin and chloroplast RNA editing. We first analyzed auxin response elements (AuxREs) present within promoters of chloroplast editing factors reported to date. We found that each has more than one AuxRE, suggesting a potential regulatory role of auxin in their expression. Further investigation unveiled that the depletion of auxin synthesis gene YUC2 reduces the expression of several editing factors. However, in yuc2 mutants, only the expression of CRR4, DYW1, ISE2, and ECD1 editing factors and the editing efficiency of their corresponding editing sites, ndhD-2 and rps14-149, were simultaneously suppressed. In addition, exogenous IAA and the overexpression of YUC2 enhanced the expression of these editing factors and the editing efficiency at the ndhD-2 and rps14-149 sites. These results suggested a direct effect of auxin upon the editing of the ndhD-2 and rps14-149 sites through the modulation of the expression of the editing factors. We further demonstrated that ARF1, a downstream transcription factor in the auxin-signaling pathway, could directly bind to and inactivate the promoters of CRR4, DYW1, and ISE2 in a dual-luciferase reporter system, thereby inhibiting their expression. Moreover, the overexpression of ARF1 in Arabidopsis significantly reduced the expression of the three editing factors and the editing efficiency at the ndhD-2 and rps14-149 sites. These data suggest that YUC2-mediated auxin biosynthesis governs the RNA-editing process through the ARF1-dependent signal transduction pathway.

LncRNA TYMSOS facilitates breast cancer metastasis and immune escape through downregulating ULBP3.

The focus of the study is to examine the function of TYMSOS in immune escape of breast cancer, which is the most frequently diagnosed malignancy among women globally. Our study demonstrated that upregulated TYMSOS was associated with unfavorable prognosis and immune escape in breast cancer. TYMSOS promoted the malignant phenotypes of breast cancer cells, and reduced the cytotoxicity of NK92 cells on these cells. CBX3 was a downstream effector in TYMSOS-induced malignant phenotypes in breast cancer cells. Mechanistic studies showed that TYMSOS facilitated CBX3-mediated transcriptional repression of ULBP3, and it also promoted SYVN1-mediated ubiquitin-proteasomal degradation of ULBP3. TYMSOS promoted cell growth, metastasis, and immune escape via CBX3/ULBP3 or SYVN1/ULBP3 axis. The in vivo studies further showed that silencing of TYMSOS repressed tumor growth and boosted NK cell cytotoxicity. In sum, TYMSOS boosted breast cancer metastasis and immune escape via CBX3/ULBP3 or SYVN1/ULBP3 axis.

A promising nucleic acid therapy drug: DNAzymes and its delivery system.

Based on the development of nucleic acid therapeutic drugs, DNAzymes obtained through in vitro selection technology in 1994 are gradually being sought. DNAzymes are single-stranded DNA molecules with catalytic function, which specifically cleave RNA under the action of metal ions. Various in vivo and in vitro models have recently demonstrated that DNAzymes can target related genes in cancer, cardiovascular disease, bacterial and viral infection, and central nervous system disease. Compared with other nucleic acid therapy drugs, DNAzymes have gained more attention due to their excellent cutting efficiency, high stability, and low cost. Here, We first briefly reviewed the development and characteristics of DNAzymes, then discussed disease-targeting inhibition model of DNAzymes, hoping to provide new insights and ways for disease treatment. Finally, DNAzymes were still subject to some restrictions in practical applications, including low cell uptake efficiency, nuclease degradation and interference from other biological matrices. We discussed the latest delivery strategy of DNAzymes, among which lipid nanoparticles have recently received widespread attention due to the successful delivery of the COVID-19 mRNA vaccine, which provides the possibility for the subsequent clinical application of DNAzymes. In addition, the future development of DNAzymes was prospected.

Auxin inhibits chlorophyll accumulation through ARF7-IAA14-mediated repression of chlorophyll biosynthesis genes in Arabidopsis.

Auxin is a well-known important phytohormone in plant that plays vital roles in almost every development process throughout plant lifecycle. However, the effect of auxin on the metabolism of chlorophyll, one of the most important pigments involved in the photosynthesis, was intertwined and the underlying mechanism remained to be explored. Here, we found the auxin-defective yuc2 yuc6 double mutant displayed dark-green leaf color with higher chlorophyll content than wildtype, suggesting a negative regulatory role of auxin in chlorophyll biosynthesis. The chloroplast number and structure in mesophyll cells were altered and the photosynthetic efficiency was improved in yuc2 yuc6. In addition, the chlorophyll level was significantly improved during seedling de-etiolation in yuc2 yuc6 mutant, and decreased dramatically under IAA treatment, confirming the inhibitory role of auxin in chlorophyll biosynthesis. The analyses of gene expression in mature leaves and de-etiolation seedlings suggested that auxin suppressed the expression of many chlorophyll biosynthesis genes, especially PROTOCHLOROPHYLLIDE OXIDOREDUCTASE A (PORA) and GENOMES UNCOUPLED 5 (GUN5). Yeast-one-hybrid and luciferase assays demonstrated that the AUXIN RESPONSE FACTOR 2 (ARF2) and ARF7 bind to the promoter of PORA and GUN5 to suppress their expression with the help of INDOLE-3-ACETIC ACID14 (IAA14). Collectively, our research explicitly unraveled the direct inhibitory role of auxin in chlorophyll biosynthesis, and provided new insight into the interplay between auxin signaling and chlorophyll metabolism.

Temporospatial Expression of Neuropeptide Substance P in Dental Pulp Stem Cells During Odontoblastic Differentiation in Vitro and Reparative Dentinogenesis in Vivo.

INTRODUCTION: Substance P (SP) is a neuropeptide released from the nervous fibers in response to injury. In addition to its association with pain and reactions to anxiety and stress, SP exerts various physiological functions by binding to the neurokinin-1 receptor (NK1R). However, the expression and role of SP in reparative dentinogenesis remain elusive. Here, we explored whether SP is involved in odontoblastic differentiation during reparative dentinogenesis. METHODS: Dental pulp stem cells (DPSCs) were isolated from healthy human dental pulp tissues and subjected to odontoblastic differentiation. The expression of SP and NK1R during odontoblastic differentiation was investigated in vitro. The effects of SP on odontoblastic differentiation of DPSCs were evaluated using alizarin red staining, alkaline phosphatase staining, and real-time polymerase chain reaction. After direct pulp capping with mineral trioxide aggregate, the expression of SP and NK1R during reparative dentin formation in rats were identified using histological and immunohistochemical staining. RESULTS: SP and NK1R expression increased during the odontoblastic differentiation of DPSCs. SP translocated to the nucleus when DPSCs were exposed to differentiation medium. NK1R was always present in the nuclei of DPSCs and odontoblast-like cells. Additionally, we discovered that 10-8 M SP marginally enhanced the odontoblastic differentiation of DPSCs, and that these effects could be impaired by the NK1R antagonist. Furthermore, SP and NK1R were expressed in odontoblast-like and dental pulp cells during reparative dentin formation in vivo. CONCLUSIONS: SP contributes to odontoblastic differentiation during reparative dentin formation by binding to the NK1R.

The PPR protein RARE1-mediated editing of chloroplast accD transcripts is required for fatty acid biosynthesis and heat tolerance in Arabidopsis.

It has been reported that Arabidopsis chloroplast accD transcripts undergo RNA editing and that loss of accD-C794 RNA editing does not affect plant growth under normal conditions. To date, the exact biological role of accD-C794 editing has remained elusive. Here, we reveal an unexpected role for accD-C794 editing in response to heat stress. Loss of accD-C794 editing results in a yellow and dwarf phenotype with decreased chloroplast gene expression under heat stress, and artificial improvement of C794-edited accD gene expression enhances heat tolerance in Arabidopsis. These data suggest that accD-C794 editing confers heat tolerance in planta. We also found that treatment with the product of acetyl coenzyme A carboxylase (ACCase) could allay mutant phenotypic characteristics and showed that a mutation in the CAC3 gene for the α-subunit of ACCase was associated with dwarfism under heat stress. These observations indicate that defective accD-C794 editing may be intrinsic to reduced ACCase activity, thereby contributing to heat sensitivity. ACCase catalyzes the committed step of de novo fatty acid (FA) biosynthesis. FA content analysis revealed that unsaturated oleic (C18:1) and linoleic acids (C18:2) were low in the accD-C794 editing-defective mutant but high in the C794-edited accD-overexpressing plants compared with the wild type. Supplying exogenous C18:1 and C18:2 could rescue the mutant phenotype, suggesting that these FAs play an essential role in tolerance to heat stress. Transmission electron microscopy observations showed that heat stress seriously affected the membrane architecture in accD editing-defective mutants but not in accD-overexpressing plants. These results provide the first evidence that accD-C794 editing regulates FA biosynthesis for maintenance of membrane structural homeostasis under heat stress.

Application and value of intravascular ultrasound for excimer laser ablation combined with drug-coated balloon in the treatment of lower limb arteriosclerotic obliterans / 中华外科杂志

Objective: To examine the value of intravascular ultrasound (IVUS) for excimer laser ablation (ELA) combined with drug-coated balloon (DCB) in treating lower limb arteriosclerotic obliterans (ASO). Methods: As a prospective case series study, patients who underwent ELA combined with DCB for lower limb ASO with the guidance of IVUS from September 2021 to March 2022 at Department of Vascular Surgery, Zhongshan Hospital, Fudan University were enrolled prospectively. Lesion characteristics, procedure-related outcomes and complications were collected. The therapy outcomes were compared with baseline data by paired t test. Results: There were 8 males and 2 females, aged (72.0±5.9) years (range: 61 to 81 years). Of all the 11 lesions, there were 8 lesions in superficial femoral artery and 3 in popliteal artery. The lesion length was (7.0±2.4) cm (range: 3.2 to 9.8 cm). There were 4 chronic totally occlusion and 7 severe stenosis. All patients underwent the operation successfully. The technical success rate was 10/11. Bailout stenting was performed in one lesion because of flow-limiting dissection. Four lesions were grade 3 to 4 in peripheral artery calcium score system, and 9 lesions with calcification arc≥180°. Larger diameter drug-coated balloons were selected in 5 lesions after measurement of intravascular ultrasound. The follow-up time was (6.0±1.9) months (range: 3 to 9 months). The ankle-brachial index of the patient was significantly improved immediately after surgery (0.97±0.13 vs. 0.48±0.18, t=-7.60, P<0.01) and at 3 months after surgery (0.95±0.12 vs. 0.48±0.18, t=-7.17, P<0.01). The 3-month primary patency rate was 11/11, the target lesion reintervention was 0 and ulcer healing rate was 3/4. Conclusion: IVUS assisted ELA in the treatment of lower limb artery lesions is safe and effective in early stage.

A mass spectrometry imaging approach on spatiotemporal distribution of multiple alkaloids in Gelsemium elegans.

Gelsemium elegans contains multiple alkaloids with pharmacological effects, thus researchers focus on the identification and application of alkaloids extracted from G. elegans. Regretfully, the spatiotemporal distribution of alkaloids in G. elegans is still unclear. In this study, the desorption electrospray ionization mass spectrometry imaging (DESI-MSI) was applied to simultaneously analyze the distribution of pharmacologically important alkaloids in different organ/tissue sections of G. elegans at different growth stages. Finally, 23 alkaloids were visualized in roots, stems and leaves at seedling stage and 19 alkaloids were observed at mature stage. In mature G. elegans, 16 alkaloids were distributed in vascular bundle region of mature roots, 15 alkaloids were mainly located in the pith region of mature stems and 2 alkaloids were enriched in epidermis region of mature stems. A total of 16 alkaloids were detected in leaf veins of mature leaves and 17 alkaloids were detected in shoots. Interestingly, diffusion and transfer of multiple alkaloids in tissues have been observed along with the development and maturation. This study comprehensively characterized the spatial metabolomics of G. elegans alkaloids, and the spatiotemporal distribution of alkaloid synthesis. In addition, the results also have reference value for the development and application of Gelsemium elegans and other medicinal plants.

[Activity of Codonopsis canescens against rheumatoid arthritis based on TLRs/MAPKs/NF-κB signaling pathways and its mechanism].

This paper aims to explore the activity of Codonopsis canescens extract against rheumatoid arthritis(RA) based on the Toll-like receptors(TLRs)/mitogen-activated protein kinases(MAPKs)/nuclear factor kappa B(NF-κB) signaling pathways and its mechanism. The ultra-performance liquid chromatography-quadrupole time-of-flight/mass spectrometry(UPLC-Q-TOF-MS) was used to identify the components of C. canescens extract. Forty-eight male SD rats were randomly divided into six groups, namely the normal group, the model group, the methotrexate(MTX) tablet group, and the low, medium, and high-dose C. canescens extract(ZDS-L, ZDS-M, and ZDS-H) groups, with 8 rats in each group. The model of collagen-induced arthritis in rats was induced by injection of bovine type Ⅱ collagen emulsion. MTX(2.5 mg·kg~(-1)), ZDS-L, ZDS-M, and ZDS-H(0.3 g·kg~(-1), 0.6 g·kg~(-1), and 1.2 g·kg~(-1)) were administrated by gavage. Rats in the normal group and the model group received distilled water. MTX was given once every three days for 28 days, and the rest medicines were given once daily for 28 days. Body weight, degree of foot swelling, arthritis index, immune organ index, synovial histopathological changes, and serum levels of tumor necrosis factor-α(TNF-α), interleukin-1ß(IL-1ß), and interleukin-6(IL-6) were observed. Protein expressions of TLR2, TLR4, NF-κB p65, p38 MAPK, and p-p38 MAPK in rats were determined by Western blot. Thirty-four main components were identified by UPLC-Q-TOF-MS, including 15 flavonoids, 7 phenylpropanoids, 4 terpenoids, 4 organic acids, 2 esters, and 2 polyalkynes. As compared with the normal group, the body weight of the model group was significantly decreased(P<0.01), and foot swelling(P<0.05, P<0.01), arthritis index(P<0.01), and the immune organ index(P<0.01) were significantly increased. The synovial histopathological injury was obviously observed in the model group. The serum levels of inflammatory factors TNF-α, IL-1ß, and IL-6 were significantly increased(P<0.01), and the protein expression levels of TLR2, TLR4, NF-κB p65, p-p38 MAPK/p38 MAPK in the synovial tissue were significantly increased(P<0.01) in the model group. As compared with the model group, the body weights of the ZDS dose groups were increased(P<0.01), and the degree of foot swelling(P<0.01) and the arthritis index were decreased(P<0.05, P<0.01). The immune organ index was decreased(P<0.01) in the ZDS dose groups, and the synovial tissue hyperplasia and inflammatory cell infiltration were alleviated. The serum levels of TNF-α, IL-1ß, and IL-6 were significantly decreased(P<0.05, P<0.01), and the protein expression levels of TLR2, TLR4, NF-κB p65, p-p38 MAPK/p38 MAPK were decreased(P<0.05, P<0.01) in the ZDS dose groups. C. canescens extract containing apigenin, tricin, chlorogenic acid, aesculin, ferulic acid, caffeic acid, and oleanolic acid has a good anti-RA effect, and the mechanism may be related to the inhibition of TLRs/MAPKs/NF-κB signaling pathways.

The role of different macrophages-derived conditioned media in dental pulp tissue regeneration.

Macrophages have been reported to play important roles in tissue repair and regeneration. While it is known that macrophages are present in the dental pulp, their role in dental pulp regeneration is not fully understood. In the present study, we investigated the effects of different phenotype macrophages conditioned medium on the cellular behaviors of hDPSCs and their extracellular matrix (cell sheets) in vitro. Moreover, twenty-four root fragments inserted with cell sheets cultured with different conditioned media were placed into the back subcutaneous space of 6-8-week-old male BALB/c nude mouse. The regenerated tissues in the root fragments were assessed via histologic analysis after 8 weeks of transplantation. M2 macrophages could promote the proliferation, migration, and osteogenic differentiation of hDPSCs. Dental pulp-like tissue with an odontoblast-like layer lining the dentinal surface and well-arranged collagen fibers was harvested in root fragment combined with M2 conditioned medium cultured cell sheet, whereas a large amount of calcium salt deposition and disorganization of collagen fibers were observed in root fragments combined with M1 conditioned medium cultured cell sheet. Therefore, promoting the transformation of M1 into M2 macrophage in dental pulp tissue regeneration may be a potential way for dental pulp regeneration via functional healing.

Identification and Functional Analysis of a Defensin CcDef2 from Coridius chinensis.

Coridius chinensis belongs to Dinidoridae, Hemiptera. Previous studies have indicated that C. chinensis contains abundant polypeptides with antibacterial and anticancer activities. Antimicrobial peptides (AMPs), as endogenous peptides with immune function, play an indispensable role in the process of biological development and immunity. AMPs have become one of the most potential substitutes for antibiotics due to their small molecular weight and broad-spectrum antimicrobial activity. In this study, a defensin CcDef2 from C. chinensis was characterized based on bioinformatics and functional analyses. The mature peptide of CcDef2 is a typical cationic peptide composed of 43 amino acid residues with five cations, and contains three intramolecular disulfide bonds and a typical cysteine-stabilized αß motif in defensins. Phylogenetic analysis showed that CcDef2 belongs to the insect defensin family. Analysis of gene expression patterns showed that CcDef2 was expressed throughout developmental stages of C. chinensis with high levels at the nymphal stage and in adult tissues tested with the highest level in the fat body. In addition, the CcDef2 expression was significantly upregulated in adults infected by bacteria. After expressed in Escherichia coli BL21(DE3) and renatured, the recombinant CcDef2 showed a significant antibacterial effect on three kinds of Gram-positive bacteria. These results indicate that CcDef2 is an excellent antibacterial peptide and a highly effective immune effector in the innate immunity of C. chinensis. This study provides a foundation for further understanding the function of CcDef2 and developing new antimicrobial drugs.

In Situ Visual Distribution of Gelsemine, Koumine, and Gelsenicine by MSI in Gelsemiumelegans at Different Growth Stages.

The distribution of pharmatically important alkaloids gelsemine, koumine, and gelsenicine in Gelsemium elegans tissues is a hot topic attracting research attention. Regretfully, the in planta visual distribution details of these alkaloids are far from clear although several researches reported the alkaloid quantification in G. elegans by LC-MS/MS. In this study, mass imaging spectrometry (MSI) was employed to visualize the in situ visualization of gelsemine, koumine, and gelsenicine in different organs and tissues of G. elegans at different growth stages, and the relative quantification of three alkaloids were performed according to the image brightness intensities captured by the desorption electrospray ionization MSI (DESI-MSI). The results indicated that these alkaloids were mainly accumulated in pith region and gradually decreased from pith to epidermis. Interestingly, three alkaloids were found to be present in higher abundance in the leaf vein. Along with the growth and development, the accumulation of these alkaloids was gradually increased in root and stem. Moreover, we employed LC-MS/MS to quantify three alkaloids and further validated the in situ distributions. The content of koumine reached 249.2 µg/g in mature roots, 272.0 µg/g in mature leaves, and 149.1 µg/g in mature stems, respectively, which is significantly higher than that of gelsemine and gelsenicine in the same organ. This study provided an accurately in situ visualization of gelsemine, koumine, and gelsenicine in G. elegans, and would be helpful for understanding their accumulation in plant and guiding application.

Highland barley Monascus purpureus Went extract ameliorates high-fat, high-fructose, high-cholesterol diet induced nonalcoholic fatty liver disease by regulating lipid metabolism in golden hamsters.

ETHNOPHARMACOLOGICAL RELEVANCE: Hepatocyte lipid accumulation is the main feature in the early stage of nonalcoholic fatty liver disease (NAFLD). Highland barley Monascus purpureus Went (HBMPW), a fermentation product of Hordeum vulgare Linn. var. nudum Hook. f. has traditionally been used as fermented foods in Tibet with the effect of reducing blood lipid in folk medicine. AIM OF THE STUDY: This study investigated the protective effects and molecular mechanism of highland barley Monascus purpureus Went extract (HBMPWE) on NAFLD in syrian golden hamster fed with high-fat, high-fructose, high-cholesterol diet (HFFCD). MATERIALS AND METHODS: HFFCD-induced NAFLD golden hamster model was established and treated with HBMPWE. Liver index, biochemical index, and hematoxylin and eosin (HE) staining were observed. Liver metabolomics and western blot analysis were employed. RESULTS: Our study found that HBMPWE ameliorated HFFCD induced dyslipidemia, weight gain and elevated the liver index. In addition, HBMPWE treatment significantly attenuated lipid accumulation in the liver and modulated lipid metabolism (sphingolipid, glycerophospholipid). Our data demonstrated that HBMPWE not only regulated the expression of proteins related to fatty acid synthesis and decomposition (SREBP-1/ACC/FAS/AceS1, PPARα/ACSL/CPT1/ACOX1), but also regulated the expression of proteins related to cholesterol synthesis and clearance (HMGCR, LDLR, CYP7A1). CONCLUSIONS: HBMPWE improved NAFLD through multiple pathways and multiple targets in body metabolism and could be used as a functional food to treat NAFLD and other lipid metabolic disorders.

Application of TGF-ß1, TIMP-1 and TIMP-2 small interfering RNAs can alleviate CCl4-induced hepatic fibrosis in rats by rebalancing Th1/Th2 cytokines.

The present study aimed to investigate the effects of TGF-ß1, tissue inhibitor of metalloproteinase (TIMP)-1 small interfering (si)RNA and TIMP-2 siRNA on hepatic fibrosis in rats and explore the T helper (Th)1/Th2 balance. Moreover, IFN-γ, IL-4 and IL-13 are the main cytokines associated with Th1/Th2 responses and have significant influence on the progression of hepatic fibrosis. The expression levels of IFN-γ, IL-4 and IL-13 in rats with hepatic fibrosis that were treated with siRNAs against the aforementioned molecules were measured using various techniques including immunohistochemical staining, western blotting and reverse transcription-quantitative PCR. The principal outcomes revealed the downregulation of IFN-γ and the upregulation of IL-4 and IL-13 in the model group compared with the normal group. Moreover, the expression of IFN-γ was significantly increased, while IL-4 and IL-13 demonstrated no significant difference in the TGF-ß1 siRNA treatment group compared with the model group. The TIMP-1 and TIMP-2 siRNA treatment groups exhibited significantly increased expression levels of IFN-γ, but lower expression levels of IL-4 and IL-13 compared with the model group. These results indicated that TIMP-1 and TIMP-2 were improved antifibrotic targets compared with TGF-ß1.

Review on the Vascularization of Organoids and Organoids-on-a-Chip.

The use of human cells for the construction of 3D organ models in vitro based on cell self-assembly and engineering design has recently increased in popularity in the field of biological science. Although the organoids are able to simulate the structures and functions of organs in vitro, the 3D models have difficulty in forming a complex vascular network that can recreate the interaction between tissue and vascular systems. Therefore, organoids are unable to survive, due to the lack of oxygen and nutrients, as well as the accumulation of metabolic waste. Organoids-on-a-chip provides a more controllable and favorable design platform for co-culture of different cells and tissue types in organoid systems, overcoming some of the limitations present in organoid culture. However, the majority of them has vascular networks that are not adequately elaborate to simulate signal communications between bionic microenvironment (e.g., fluid shear force) and multiple organs. Here, we will review the technological progress of the vascularization in organoids and organoids-on-a-chip and the development of intravital 3D and 4D bioprinting as a new way for vascularization, which can aid in further study on tissue or organ development, disease research and regenerative medicine.

The Role of Small Extracellular Vesicles Derived from Lipopolysaccharide-preconditioned Human Dental Pulp Stem Cells in Dental Pulp Regeneration.

INTRODUCTION: Regenerative endodontics has created a desirable shift in the treatment paradigm despite current limitations of regenerative outcomes. Mesenchymal stem cells (MSCs) facilitate tissue regeneration and repair in a mild inflammatory environment. Small extracellular vesicles (sEVs) derived from MSCs play an imperative role in the paracrine modulation of regenerative responses modulated by MSCs. However, it remains unknown whether MSCs enhance dental pulp regeneration or whether this enhancement is mediated by sEVs in a mild inflammatory environment. The present study aimed to elucidate the effects of sEVs originated from lipopolysaccharide (LPS)-preconditioned human dental pulp stem cells (hDPSCs) on dental pulp regeneration. METHODS: All sEVs were isolated from hDPSCs cultured with or without LPS (ie, N-sEVs and L-sEVs, respectively). The effect of N-sEVs and L-sEVs on proliferation, migration, angiogenesis, and differentiation of rat bone marrow MSCs was identified in vitro. Moreover, N-sEVs or L-sEVs were implanted into rat pulpless root canal models, and the regenerated tissue in root canals was assessed via hematoxylin-eosin staining, Masson staining, and immunohistochemistry after 30 days of transplantation. RESULTS: Both N-sEVs and L-sEVs could modulate BMSC proliferation, migration, angiogenesis, and differentiation. Both kinds of sEVs enhanced the structure of the regenerated tissue closer to that of a normal dental pulp in vivo. L-sEVs had a more significant effect than N-sEVs. CONCLUSIONS: sEVs released by hDPSCs in a mild inflammatory microenvironment are capable of facilitating the regeneration of dental pulp through functional healing instead of scar healing, which has potential applications in regenerative endodontics.

Long-term results of extensive aortoiliac occlusive disease (EAIOD) treated by endovascular therapy and risk factors for loss of primary patency.

BACKGROUND: Although endovascular therapy has been widely used for focal aortoiliac occlusive disease (AIOD), its performance for extensive AIOD (EAIOD) is not fully evaluated. We aimed to demonstrate the long-term results of EAIOD treated by endovascular therapy and to identify the potential risk factors for the loss of primary patency. METHODS: Between January 2008 and June 2018, patients with a clinical diagnosis of the 2007 TransAtlantic Inter-Society Consensus II (TASC II) C and D AIOD lesions who underwent endovascular treatment in our institution were enrolled. Demographic, diagnosis, procedure characteristics, and follow-up information were reviewed. Univariate analysis was used to identify the correlation between the variables and the primary patency. A multivariate logistic regression model was used to identify the independent risk factors associated with primary patency. Five- and 10-year primary and secondary patency, as well as survival rates, were calculated by Kaplan-Meier analysis. RESULTS: A total of 148 patients underwent endovascular treatment in our center. Of these, 39.2% were classified as having TASC II C lesions and 60.8% as having TASC II D lesions. The technical success rate was 88.5%. The mean follow-up time was 79.2 ±â€Š29.2 months. Primary and secondary patency was 82.1% and 89.4% at 5 years, and 74.8% and 83.1% at 10 years, respectively. The 5-year survival rate was 84.2%. Compared with patients without loss of primary patency, patients with this condition showed significant differences in age, TASC II classification, infrainguinal lesions, critical limb ischemia (CLI), and smoking. Multivariate logistic regression analysis showed age <61 years (adjusted odds ratio [aOR]: 6.47; 95% CI: 1.47-28.36; P = 0.01), CLI (aOR: 7.81; 95% CI: 1.92-31.89; P = 0.04), and smoking (aOR: 10.15; 95% CI: 2.79-36.90; P < 0.01) were independent risk factors for the loss of primary patency. CONCLUSION: Endovascular therapy was an effective treatment for EAIOD with encouraging patency and survival rate. Age <61 years, CLI, and smoking were independent risk factors for the loss of primary patency.

3D Visualization and Volume-Based Quantification of Rice Chalkiness In Vivo by Using High Resolution Micro-CT.

BACKGROUND: Rice quality research attracts attention worldwide. Rice chalkiness is one of the key indexes determining rice kernel quality. The traditional rice chalkiness measurement methods only use milled rice as materials and are mainly based on naked-eye observation or area-based two-dimensional (2D) image analysis and the results could not represent the three-dimensional (3D) characteristics of chalkiness in the rice kernel. These methods are neither in vivo thus are unable to analyze living rice seeds for high throughput screening of rice chalkiness phenotype. RESULTS: Here, we introduced a novel method for 3D visualization and accurate volume-based quantification of rice chalkiness in vivo by using X-ray microcomputed tomography (micro-CT). This approach not only develops a novel volume-based method to measure the 3D rice chalkiness index, but also provides a high throughput solution for rice chalkiness phenotype analysis by using living rice seeds. CONCLUSIONS: Our method could be a new powerful tool for rice chalkiness measurement, especially for high throughput chalkiness phenotype screening using living rice seeds. This method could be used in chalkiness phenotype identification and screening, and would greatly promote the basic research in rice chalkiness regulation as well as the quality evaluation in rice production practice.

The Stress Concentration Mechanism of Pores Affecting the Tensile Properties in Vacuum Die Casting Metals.

The absolute pressure strongly affects the porosity and mechanical properties of castings produced by vacuum high-pressure die casting (V-HPDC) technology. The pore size, quantity and distribution of AlSi9Cu3 samples under three absolute pressures were evaluated by X-ray tomography and optical and electron microscopy. The paper presents an elaboration the stress concentration mechanism of pores affecting the tensile properties. According to a mathematical analysis of a sample under uniaxial stress, the greater the radius of the pore, the higher the stress value is at the pore perimeter. When the absolute pressure drops from 1013 mbar to 100 mbar, the porosity decreases from 6.8% to 2.8%, and the pore number and mean size decreases. In tensile tests, the pore sizes of the fracture surface decrease with decreasing absolute pressure, and the pore distribution becomes uniform. The tensile properties and extensibility of the sample are improved, and the microscopic fracture surface of the sample changes from cleavage fracture to quasi-cleavage fracture. The number, size and distribution of pores in die casting collectively affect the properties of the sample. Large-size or complex pores or pores with concentrated distributions produce large stress concentrations, decreasing the strength of the metal.

Phytohormone dynamics in developing endosperm influence rice grain shape and quality.

Hormones are important signaling molecules regulating developmental processes and responses to environmental stimuli in higher plants. Rice endosperm, the portion of the seed surrounding the embryo, is the main determinant of rice grain shape and yield; however, the dynamics and exact functions of phytohormones in developing endosperm remain elusive. Through a systemic study including transcriptome analysis, hormone measurement, and transgene-based endosperm-specific expression of phytohormone biosynthetic enzymes, we demonstrated that dynamic phytohormone levels play crucial roles in the developing rice endosperm, particularly in regard to grain shape and quality. We detected diverse, differential, and dramatically changing expression patterns of genes related to hormone biosynthesis and signaling during endosperm development, especially at early developmental stages. Liquid chromatography measurements confirmed the dynamic accumulation of hormones in developing endosperm. Further transgenic analysis performed on plants expressing hormone biosynthesis genes driven by an endosperm-specific promoter revealed differential effects of the hormones, especially auxin and brassinosteroids, in regulating grain shape and quality. Our studies help elucidate the distinct roles of hormones in developing endosperm and provide novel and useful tools for influencing crop seed shape and yield.