Phytochromes enhance SOS2-mediated PIF1 and PIF3 phosphorylation and degradation to promote Arabidopsis salt tolerance.

Soil salinity is one of the most detrimental abiotic stresses affecting plant survival, and light is a core environmental signal regulating plant growth and responses to abiotic stress. However, how light modulates the plant's response to salt stress remains largely obscure. Here, we show that Arabidopsis (Arabidopsis thaliana) seedlings are more tolerant to salt stress in the light than in the dark, and that the photoreceptors phytochrome A (phyA) and phyB are involved in this tolerance mechanism. We further show that phyA and phyB physically interact with the salt tolerance regulator SALT OVERLY SENSITIVE2 (SOS2) in the cytosol and nucleus, and enhance salt-activated SOS2 kinase activity in the light. Moreover, SOS2 directly interacts with and phosphorylates PHYTOCHROME-INTERACTING FACTORS PIF1 and PIF3 in the nucleus. Accordingly, PIFs act as negative regulators of plant salt tolerance, and SOS2 phosphorylation of PIF1 and PIF3 decreases their stability and relieves their repressive effect on plant salt tolerance in both light and dark conditions. Together, our study demonstrates that photoactivated phyA and phyB promote plant salt tolerance by increasing SOS2-mediated phosphorylation and degradation of PIF1 and PIF3, thus broadening our understanding of how plants adapt to salt stress according to their dynamic light environment.

Phosphorylation of RhoGDI1, a Rho GDP dissociation inhibitor, regulates root hair development in Arabidopsis under salt stress.

To ensure optimal growth, plants actively regulate their growth and development based on environmental changes. Among these, salt stress significantly influences growth and yield. In this study, we demonstrate that the growth of root hairs of salt-stressed Arabidopsis thaliana seedlings is regulated by the SALT OVERLY SENSITIVE 2 (SOS2)-GUANOSINE NUCLEOTIDE DIPHOSPHATE DISSOCIATION INHIBITOR 1 (RhoGDI1)-Rho GTPASE OF PLANTS 2 (ROP2) module. We show here that the kinase SOS2 is activated by salt stress and subsequently phosphorylates RhoGDI1, a root hair regulator, thereby decreasing its stability. This change in RhoGDI1 abundance resulted in a fine-tuning of polar localization of ROP2 and root hair initiation followed by polar growth, demonstrating how SOS2-regulated root hair development is critical for plant growth under salt stress. Our results reveal how a tissue-specific response to salt stress balances the relationship of salt resistance and basic growth.

Inflammation-related molecular signatures involved in the anticancer activities of brigatinib as well as the prognosis of EML4-ALK lung adenocarcinoma patient.

Although ALK tyrosine kinase inhibitors (ALK-TKIs) have shown remarkable benefits in EML4-ALK positive NSCLC patients compared to conventional chemotherapy, the optimal sequence of ALK-TKIs treatment remains unclear due to the emergence of primary and acquired resistance and the lack of potential prognostic biomarkers. In this study, we systematically explored the validity of sequential ALK inhibitors (alectinib, lorlatinib, crizotinib, ceritinib and brigatinib) for a heavy-treated patient with EML4-ALK fusion via developing an in vitro and in vivo drug testing system based on patient-derived models. Based on the patient-derived models and clinical responses of the patient, we found that crizotinib might inhibit proliferation of EML4-ALK positive tumors resistant to alectinib and lorlatinib. In addition, NSCLC patients harboring the G1269A mutation, which was identified in alectinib, lorlatinib and crizotinib-resistant NSCLC, showed responsiveness to brigatinib and ceritinib. Transcriptomic analysis revealed that brigatinib suppressed the activation of multiple inflammatory signaling pathways, potentially contributing to its anti-tumor activity. Moreover, we constructed a prognostic model based on the expression of IL6, CXCL1, and CXCL5, providing novel perspectives for predicting prognosis in EML4-ALK positive NSCLC patients. In summary, our results delineate clinical responses of sequential ALK-TKIs treatments and provide insights into the mechanisms underlying the superior effects of brigatinib in patients harboring ALKG1269A mutation and resistant towards alectinib, lorlatinib and crizotinib. The molecular signatures model based on the combination of IL6, CXCL1 and CXCL5 has the potential to predict prognosis of EML4-ALK positive NSCLC patients.

Risk factors associated with COVID-19 pneumonia in Chinese patients with pre-existing interstitial lung disease during the SARS-CoV-2 pandemic.

In China, the emergence of a nationally widespread epidemic infection of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) has appeared within a month since December 7, 2022. To evaluate the risk factors for suffering from coronavirus disease 2019 (COVID-19) pneumonia due to infection with SARS-CoV-2 in different kinds of interstitial lung disease (ILD) patients with diverse immunizations, we conducted this retrospective study on 525 patients with ILDs who underwent regular follow-up in our ILD clinic. Among them, 128 ILD patients (24.4%) suffered from COVID-19 pneumonia after SARS-CoV-2 infection. Patients were older with a male predominance in the pneumonia group than in the nonpneumonia group (65.0 ± 10.0 years vs. 56.4 ± 11.7 years, p < 0.001, 55.5% vs. 39.5%, p = 0.002, respectively). Connective tissue disease-associated ILD (CTD-ILD) (25%), idiopathic pulmonary fibrosis (23.4%), and interstitial pneumonia with autoimmune features (21.1%) were the main pre-existing ILDs in the pneumonia group. In Cox multivariable analysis, only male sex and corticosteroid use were risk factors for COVID-19 pneumonia after infection. Two or three doses of vaccination were a protective factor for pre-existing ILD patients suffering from COVID-19 pneumonia. More than two doses of vaccination were strongly recommended for pre-existing ILD patients, particularly for males who were administered corticosteroids.

Deubiquitinating enzyme JOSD2 affects susceptibility of non-small cell lung carcinoma cells to anti-cancer drugs through DNA damage repair. / åŽ»æ³›ç´ åŒ–é ¶JOSD2通过调控DNA损伤修复影响非小细胞肺癌细胞对抗肿瘤药物的敏感性.

OBJECTIVES: To investigate the effects and mechanisms of deubiquitinating enzyme Josephin domain containing 2 (JOSD2) on susceptibility of non-small cell lung carcinoma (NSCLC) cells to anti-cancer drugs. METHODS: The transcriptome expression and clinical data of NSCLC were downloaded from the Gene Expression Omnibus. Principal component analysis and limma analysis were used to investigate the deubiquitinating enzymes up-regulated in NSCLC tissues. Kaplan-Meier analysis was used to investigate the relationship between the expression of deubiquitinating enzymes and overall survival of NSCLC patients. Gene ontology enrichment and gene set enrichment analysis (GSEA) were used to analyze the activation of signaling pathways in NSCLC patients with high expression of JOSD2. Gene set variation analysis and Pearson correlation were used to investigate the correlation between JOSD2 expression levels and DNA damage response (DDR) pathway. Western blotting was performed to examine the expression levels of JOSD2 and proteins associated with the DDR pathway. Immunofluorescence was used to detect the localization of JOSD2. Sulforhodamine B staining was used to examine the sensitivity of JOSD2-knock-down NSCLC cells to DNA damaging drugs. RESULTS: Compared with adjacent tissues, the expression level of JOSD2 was significantly up-regulated in NSCLC tissues (P<0.05), and was significantly correlated with the prognosis in NSCLC patients (P<0.05). Compared with the tissues with low expression of JOSD2, the DDR-related pathways were significantly upregulated in NSCLC tissues with high expression of JOSD2 (all P<0.05). In addition, the expression of JOSD2 was positively correlated with the activation of DDR-related pathways (all P<0.01). Compared with the control group, overexpression of JOSD2 significantly promoted the DDR in NSCLC cells. In addition, DNA damaging agents significantly increase the nuclear localization of JOSD2, whereas depletion of JOSD2 significantly enhanced the sensitivity of NSCLC cells to DNA damaging agents (all P<0.05). CONCLUSIONS: Deubiquitinating enzyme JOSD2 may regulate the malignant progression of NSCLC by promoting DNA damage repair pathway, and depletion of JOSD2 significantly enhances the sensitivity of NSCLC cells to DNA damaging agents.

The effect of PLK1 inhibitor in osimertinib resistant non-small cell lung carcinoma cells. / Poloæ ·æ¿€é ¶1抑制剂在奥希替尼耐药的非小细胞肺癌细胞中的作用.

OBJECTIVES: To investigate the effects of PLK1 inhibitors on osimertinib-resistant non-small cell lung carcinoma (NSCLC) cells and the anti-tumor effect combined with osimertinib. METHODS: An osimertinib resistant NCI-H1975 cell line was induced by exposure to gradually increasing drug concentrations. Osimertinib-resistant cells were co-treated with compounds from classical tumor pathway inhibitor library and osimertinib to screen for compounds with synergistic effects with osimertinib. The Gene Set Enrichment Analysis (GSEA) was used to investigate the activated signaling pathways in osimertinib-resistant cells; sulforhodamine B (SRB) staining was used to investigate the effect of PLK1 inhibitors on osimertinib-resistant cells and the synergistic effect of PLK1 inhibitors combined with osimertinib. RESULTS: Osimertinib-resistance in NCI-H1975 cell (resistance index=43.45) was successfully established. The PLK1 inhibitors GSK 461364 and BI 2536 had synergistic effect with osimertinib. Compared with osimertinib-sensitive cells, PLK1 regulatory pathway and cell cycle pathway were significantly activated in osimertinib-resistant cells. In NSCLC patients with epidermal growth factor receptor mutations treated with osimertinib, PLK1 mRNA levels were negatively correlated with progression free survival of patients (R=－0.62, P<0.05), indicating that excessive activation of PLK1 in NSCLC cells may cause cell resistant to osimertinib. Further in vitro experiments showed that IC50 of PLK1 inhibitors BI 6727 and GSK 461364 in osimertinib-resistant cells were lower than those in sensitive ones. Compared with the mono treatment of osimertinib, PLK1 inhibitors combined with osimertinib behaved significantly stronger effect on the proliferation of osimertinib-resistant cells. CONCLUSIONS: PLK1 inhibitors have a synergistic effect with osimertinib on osimertinib-resistant NSCLC cells which indicates that they may have potential clinical value in the treatment of NSCLC patients with osimertinib resistance.

Sclerostin is a promising therapeutic target for oral inflammation and regenerative dentistry.

Sclerostin is the protein product of the SOST gene and is known for its inhibitory effects on bone formation. The monoclonal antibody against sclerostin has been approved as a novel treatment method for osteoporosis. Oral health is one of the essential aspects of general human health. Hereditary bone dysplasia syndrome caused by sclerostin deficiency is often accompanied by some dental malformations, inspiring the therapeutic exploration of sclerostin in the oral and dental fields. Recent studies have found that sclerostin is expressed in several functional cell types in oral tissues, and the expression level of sclerostin is altered in pathological conditions. Sclerostin not only exerts similar negative outcomes on the formation of alveolar bone and bone-like tissues, including dentin and cementum, but also participates in the development of oral inflammatory diseases such as periodontitis, pulpitis, and peri-implantitis. This review aims to highlight related research progress of sclerostin in oral cavity, propose necessary further research in this field, and discuss its potential as a therapeutic target for dental indications and regenerative dentistry.

The PYR-PP2C-CKL2 module regulates ABA-mediated actin reorganization during stomatal closure.

Limiting water loss by reducing transpiration helps plants survive when water is limited. Under drought stress, abscisic acid (ABA)-mediated gene expression and anion channel activation regulate stomatal closure and stress responses. ABA-induced actin reorganization also affects stomatal closure, but the underlying molecular mechanism remains unclear. In this study, we discovered that under nonstress conditions, the clade A PP2C phosphatases, such as ABI1 and ABI2, interact with CKL2 and inhibit its kinase activity in Arabidopsis. Under drought stress, CKL2 kinase activity was released through the formation of a complex containing ABA, PP2C and a PYR1/PYL/RCAR family (PYL) receptor. The activated CKL2 regulating actin reorganization is another important process to maintain stomatal closure besides ABA-activated SnRK2 signaling. Moreover, CKL2 phosphorylated PYR1-LIKE 1, ABI1 and ABI2 at amino acid residues conserved among PYLs and PP2Cs, and stabilized ABI1 protein. Our results reveal that ABA signaling regulates actin reorganization to maintain stomatal closure during drought stress, and the feedback regulation of PYL1, ABI1 and ABI2 by the CKL2 kinase might fine-tune ABA signaling and affect plant ABA responses.

Severe asthma as the initial clinical manifestation of IgG4-related disease: a retrospective clinical study.

BACKGROUND: Respiratory involvement is common in immunoglobulin G4-related disease (IgG4-RD). However, severe asthma as the initial clinical manifestation of IgG4-RD is rare and might be neglected by respiratory clinicians. We aimed to explore the clinical characteristics and prognoses of patients with immunoglobulin G4-related disease (IgG4-RD) manifesting as severe asthma. METHODS: A retrospective analysis of the clinical characteristics and prognoses of patients with severe asthma who were eventually diagnosed with IgG4-RD was performed in the Peking Union Medical College Hospital from 2013 to 2019. RESULTS: Twelve patients (5males, 7 females) were included. The mean age at enrollment and age of asthma onset were 59.4 ± 10.1 and 53.8 ± 10.4 years, respectively. The mean duration of asthma symptoms was 5.7 ± 2.0 years. In all patients, the proportion (25.1 ± 10.3%) and count (2.0 ± 1.1) × 109/L of eosinophils in peripheral blood increased. Additionally, all patients exhibited elevated total immunoglobulin E [IgE, (1279.3 ± 1257.9) KU/L] and IgG4 (9155.8 ± 9247.6) mg/dL. Bronchial wall thickening (n = 11) and mediastinal/hilar lymphadenopathy (n = 11) were major chest CT manifestations. All were pathologically diagnosed through surgical biopsy; submandibular gland (n = 8), supraclavicular lymph node (n = 2), stomach (n = 1), rashes (n = 1), lacrimal gland (n = 1) and thoracoscopic lung (n = 1) biopsies were performed. Asthma was well controlled by oral glucocorticoids (GCs), but some patients relapsed during tapering (n = 11). The refractory condition was controlled after increasing the dosage of GCs and add-on immunosuppressants. CONCLUSIONS: For patients with middle age-onset severe asthma with elevated eosinophils, total IgE and IgG4 levels and available salivary gland ultrasound imaging, ruling out IgG4-RD is recommended. GCs used in combination with immunosuppressants is recommended to prevent relapse.

Nanomaterials and hepatic disease: toxicokinetics, disease types, intrinsic mechanisms, liver susceptibility, and influencing factors.

The widespread use of nanomaterials (NMs) has raised concerns that exposure to them may introduce potential risks to the human body and environment. The liver is the main target organ for NMs. Hepatotoxic effects caused by NMs have been observed in recent studies but have not been linked to liver disease, and the intrinsic mechanisms are poorly elucidated. Additionally, NMs exhibit varied toxicokinetics and induce enhanced toxic effects in susceptible livers; however, thus far, this issue has not been thoroughly reviewed. This review provides an overview of the toxicokinetics of NMs. We highlight the possibility that NMs induce hepatic diseases, including nonalcoholic steatohepatitis (NASH), fibrosis, liver cancer, and metabolic disorders, and explore the underlying intrinsic mechanisms. Additionally, NM toxicokinetics and the potential induced risks in the livers of susceptible individuals, including subjects with liver disease, obese individuals, aging individuals and individuals of both sexes, are summarized. To understand how NM type affect their toxicity, the influences of the physicochemical and morphological (PCM) properties of NMs on their toxicokinetics and toxicity are also explored. This review provides guidance for further toxicological studies on NMs and will be important for the further development of NMs for applications in various fields.

Complete genome sequence of a Chinese isolate of pepper vein yellows virus and evolutionary analysis based on the CP, MP and RdRp coding regions.

The genome sequence of pepper vein yellows virus (PeVYV) (PeVYV-HN, accession number KP326573), isolated from pepper plants (Capsicum annuum L.) grown at the Hunan Vegetables Institute (Changsha, Hunan, China), was determined by deep sequencing of small RNAs. The PeVYV-HN genome consists of 6244 nucleotides, contains six open reading frames (ORFs), and is similar to that of an isolate (AB594828) from Japan. Its genomic organization is similar to that of members of the genus Polerovirus. Sequence analysis revealed that PeVYV-HN shared 92% sequence identity with the Japanese PeVYV genome at both the nucleotide and amino acid levels. Evolutionary analysis based on the coat protein (CP), movement protein (MP), and RNA-dependent RNA polymerase (RdRP) showed that PeVYV could be divided into two major lineages corresponding to their geographical origins. The Asian isolates have a higher population expansion frequency than the African isolates. Negative selection and genetic drift (founder effect) were found to be the potential drivers of the molecular evolution of PeVYV. Moreover, recombination was not the distinct cause of PeVYV evolution. This is the first report of a complete genomic sequence of PeVYV in China.

Biological Effect of Ultraviolet Photocatalysis on Nanoscale Titanium with a Focus on Physicochemical Mechanism.

Physicochemical properties, regulated by various surface modifications, influence the biological performance of materials. The interaction between surface charge and biomolecules is key to understanding the mechanism of surface-tissue integration. The objective of this study was to evaluate the biological response to a nanoscale titanium surface after ultraviolet (UVC, λ = 250 ± 20 nm) irradiation and to analyze the effects via a physicochemical mechanism. The surface characteristics were evaluated by field-emission scanning electron microscopy, X-ray photoelectron spectroscopy, surface profilometry, and contact angle assay. In addition, we applied the zeta-potential, a direct method to measure the electrostatic charge on UV-treated and UV-untreated titanium nanotube surfaces. The effect of the Ti surface after UV treatment on the biological process was determined by analyzing bovine serum albumin (BSA) adsorption and osteoblast-like MG-63 early adhesion, morphology, cytoskeletal arrangement, proliferation, and focal adhesion. Compared to an anodized titanium nanotube coating, UV irradiation altered the contact angles on the control surface from 51.5° to 6.2° without changing the surface topography or roughness. Furthermore, titanium nanotubes after UV treatment showed a significant reduction in the content of acidic hydroxyl groups and held less negative charge than the anodized coating. With regard to the biological response, along with an enhanced capability to adsorb BSA, osteoblasts exhibited higher colonization and viability on the UV-treated material. The results suggest that UV treatment enhances the biocompatibility by reducing the electrostatic repulsion between biomaterials and biomolecules.

Predicting High-risk Capsular Features in Pleomorphic Adenoma of the Parotid Gland Through a Nomogram Model Based on ADC Imaging.

RATIONALE AND OBJECTIVES: Based on Apparent Diffusion Coefficient (ADC) images, a nomogram model is established to accurately predict the high-risk capsular characteristics associated with pleomorphic adenoma of the parotid gland (PAP) recurrence. MATERIALS AND METHODS: This retrospective study analyzed 190 patients with PAPs. Significant clinical radiological factors were identified through univariate difference analysis and multivariate regression analysis. The optimal threshold was determined by analyzing the average ADC value of the entire tumor, using the best Youden index and sensitivity analysis, and tumor subregions were delineated accordingly. Three radiomic models were constructed for the whole tumor and for high/low ADC areas, with the best model determined through statistical analysis. Ultimately, a nomogram model was constructed by combining the independent predictive factor of high-risk capsular features with the optimal radiomic predictive score. Model performance was comprehensively assessed by the area under the receiver operating characteristic curve (ROC AUC), accuracy, sensitivity, and specificity. RESULTS: The best ADC division threshold as 1.25 × 10-3 mm2/s. Multivariate analysis identified High-ADC Zone Volume Percentage as an independent predictor for PAPs with high-risk capsular characteristics. The radiomic model based on the low ADC tumor subregion was optimal (AUC 0.899). The nomogram model, combining independent predictors and optimal imaging studies predictive score, demonstrated high performance (AUC 0.909). Decision curve analysis confirmed the nomogram's clinical applicability. CONCLUSION: The nomogram model constructed from ADC quantitative imaging can predict PAPs patients with high-risk capsular features. These patients require intraoperative preventive measures to avoid tumor spillage and residuals, as well as extended postoperative follow-up.

Development and validation of a nomogram to predict leptomeningeal metastases in lung adenocarcinoma: Cervical lymph node metastasis is an important association factor.

BACKGROUND: The goal of this study was to create a nomogram using routine parameters to predict leptomeningeal metastases (LMs) in advanced lung adenocarcinoma (LAC) patients to prevent needless exams or lumbar punctures and to assist in accurately diagnosing LMs. METHODS: Two hundred and seventy-three patients with LMs and brain metastases were retrospectively reviewed and divided into derivation (n = 191) and validation (n = 82) cohorts using a 3:7 random allocation. All LAC patients with LMs had positive cerebrospinal fluid cytology results and brain metastases confirmed by magnetic resonance imaging. Binary logistic regression with backward stepwise selection was used to identify significant characteristics. A predictive nomogram based on the logistic model was assessed through receiver operating characteristic curves. The validation cohort and Hosmer-Lemeshow test were used for internal validation of the nomogram. RESULTS: Five clinicopathological parameters, namely, gene mutations, surgery at the primary lung cancer site, clinical symptoms of the head, N stage, and therapeutic strategy, were used as predictors of LMs. The area under the curve was 0.946 (95% CI 0.912-0.979) for the training cohort and 0.861 (95% CI 0.761-0.961) for the internal validation cohort. There was no significant difference in performance between the two cohorts (p = 0.116). In the internal validation, calibration plots revealed that the nomogram predictions were well suited to the actual outcomes. CONCLUSIONS: We created a user-friendly nomogram to predict LMs in advanced lung cancer patients, which could help guide treatment decisions and reduce unnecessary lumbar punctures.

Cancer-associated fibroblasts drive early pancreatic cancer cell invasion via the SOX4/MMP11 signalling axis.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by abundant cancer-associated fibroblasts (CAFs), early perineural invasion (PNI) and microvascular invasion (MVI). However, the differentiation trajectories and underlying molecular mechanisms of CAFs in PDAC early invasion have not been fully elucidated. In this study, we integrated and reanalysed single-cell data from the National Geoscience Data Centre (NGDC) database and confirmed that myofibroblast-like CAFs (myCAFs) mediated epithelial-mesenchymal transformation (EMT) and enhanced the invasion abilities of PDAC cells by secreting regulators of angiogenesis and metastasis. Furthermore, we constructed a differentiation trajectory of CAFs and revealed that reprogramming from iCAFs to myCAFs was associated with poor prognosis. Mechanistically, SOX4 was aberrantly activated in myCAFs, which promoted the secretion of MMP11 and eventually induced early cancer cell invasion. Together, our results provide a comprehensive transcriptomic overview of PDAC patients with early invasion and reveal the intercellular crosstalk between myCAFs and cancer cells, which suggests potential targets for early invasion PDAC therapy.

Tacrolimus alleviates pulmonary fibrosis progression through inhibiting the activation and interaction of ILC2 and monocytes.

Idiopathic pulmonary fibrosis (IPF) is a heterogeneous group of lung diseases with different etiologies and characterized by progressive fibrosis. This disease usually causes pulmonary structural remodeling and decreased pulmonary function. The median survival of IPF patients is 2-5 years. Predominantly accumulation of type II innate immune cells accelerates fibrosis progression by secreting multiple pro-fibrotic cytokines. Group 2 innate lymphoid cells (ILC2) and monocytes/macrophages play key roles in innate immunity and aggravate the formation of pro-fibrotic environment. As a potent immunosuppressant, tacrolimus has shown efficacy in alleviating the progression of pulmonary fibrosis. In this study, we found that tacrolimus is capable of suppressing ILC2 activation, monocyte differentiation and the interaction of these two cells. This effect further reduced activation of monocyte-derived macrophages (Mo-M), thus resulting in a decline of myofibroblast activation and collagen deposition. The combination of tacrolimus and nintedanib was more effective than either drug alone. This study will reveal the specific process of tacrolimus alleviating pulmonary fibrosis by regulating type II immunity, and explore the potential feasibility of tacrolimus combined with nintedanib in the treatment of pulmonary fibrosis. This project will provide new ideas for clinical optimization of anti-pulmonary fibrosis drug strategies.

Construction of a PbII coordination polymer from a semi-rigid ditopic 2,2-biimidazole derivative: synthesis, crystal structure and characterization.

A new PbII coordination polymer, poly[0.75(aqua)[µ3-4,4'-(1H,1'H-[2,2'-biimidazole]-1,1'-diyl)dibenzoato-κ5O,O';N;O'',O''']]lead(II)] 1.25-hydrate], {[Pb(C20H12N4O4)(H2O)0.75]·1.25H2O}n or {[Pb(L)(H2O)0.75]·1.25H2O}n (1) [H2L = 4,4'-(1H,1'H-[2,2'-biimidazole]-1,1'-diyl)dibenzoic acid], was synthesized under solvothermal reaction conditions and characterized using microanalysis, IR spectroscopy and thermogravimetric analysis. Single-crystal structure analysis reveals that a two-dimensional corrugated layer structure is formed in 1 and that neighbouring layers are further extended into a three-dimensional structure by hydrogen-bonding interactions. In addition, a fluorescence sensing experiment towards Cu2+ based on the polymeric PbII complex was carried out.

Effect of glycosaminoglycans with different degrees of sulfation on chondrogenesis.

OBJECTIVES: This study aims to investigate the effects and mechanisms of chondroitin sulfate (CS), dermatan sulfate (DS), and heparin (HEP) on chondrogenesis of murine chondrogenic cell line (ATDC5) cells and the maintenance of murine articular cartilage in vitro. METHODS: ATDC5 and articular cartilage tissue explant were cultured in the medium containing different sulfated glycosaminoglycans. Cell proliferation, differentiation, cartilage formation, and mechanism were observed using cell proliferation assay, Alcian blue staining, real-time quantitative polymerase chain reaction (RT-qPCR), and Western blot, respectively. RESULTS: Results showed that HEP and DS primarily activated the bone morphogenetic protein (BMP) signal pathway, while CS primarily activated the protein kinase B (AKT) signal pathway, further promoted ATDC5 cell proliferation and matrix production, and increased Sox9, Col2a1, and Aggrecan expression. CONCLUSIONS: This study investigated the differences and mechanisms of different sulfated glycosaminoglycans in chondrogenesis and cartilage homeostasis maintenance. HEP promotes cartilage formation and maintains the normal state of cartilage tissue in vitro, while CS plays a more effective role in the regeneration of damaged cartilage tissue.

Peptide modified geniposidic acid targets bone and effectively promotes osteogenesis.

Background: Geniposidic acid (GPA), one of the active components of Eucommia ulmoides, promote bone formation and treat osteoporosis by activating farnesoid X receptor (FXR). However, GPA has low oral availability and lack of bone targeting in the treatment of bone related diseases. With the development of modern technology, small molecules, amino acids, or aptamers are used for biological modification of drugs and target cells in bone tissue, which has become the trend of bone targeted research. Methods: In this study, SDSSD (an osteoblast-targeting peptide) were modified in GPA using Fmoc solid-phase synthesis technique to form a new SDSSD-GPA conjugate (SGPA). The bone targeting of SGPA was evaluated using in vivo imaging and cell co-culture. In vitro, the effect of SGPA on cytotoxicity, osteoblastic activity, and mineralization ability were studied in mouse primary osteoblasts (OBs). In vivo, the therapeutic effect of SGPA on osteoporosis using an ovariectomized (OVX) mouse model. The bone mass, histomorphometry, serum biochemical parameters, and the molecular mechanism were evaluated. Results: SGPA was enriched in OBs and tends to accumulate in bone tissue. In vitro, SGPA significantly enhanced the osteogenic activity and mineralization of OBs compared with GPA. In vivo, SGPA enhanced serum BALP and P1NP levels, increased the trabecular bone mass of the mice, and SGPA administration have a higher bone mineralization deposition rate than the GPA-treated mice. Moreover, SGPA significantly activated FXR and Runt-related transcription factor 2 (RUNX2). Conclusions: Collectively, SGPA is enriched into OBs, and promotes bone formation by activating FXR-RUNX2 signalling, effectively treating osteoporosis at relatively low doses. The translational potential of this article: This study demonstrates a more efficient and safe application of GPA in treating osteoporosis, provide a new concept for the bone targeted application of natural compounds.

Prospective applications of extracellular vesicle-based therapies in regenerative medicine: implications for the use of dental stem cell-derived extracellular vesicles.

In the 21st century, research on extracellular vesicles (EVs) has made remarkable advancements. Recently, researchers have uncovered the exceptional biological features of EVs, highlighting their prospective use as therapeutic targets, biomarkers, innovative drug delivery systems, and standalone therapeutic agents. Currently, mesenchymal stem cells stand out as the most potent source of EVs for clinical applications in tissue engineering and regenerative medicine. Owing to their accessibility and capability of undergoing numerous differentiation inductions, dental stem cell-derived EVs (DSC-EVs) offer distinct advantages in the field of tissue regeneration. Nonetheless, it is essential to note that unmodified EVs are currently unsuitable for use in the majority of clinical therapeutic scenarios. Considering the high feasibility of engineering EVs, it is imperative to modify these EVs to facilitate the swift translation of theoretical knowledge into clinical practice. The review succinctly presents the known biotherapeutic effects of odontogenic EVs and the underlying mechanisms. Subsequently, the current state of functional cargo loading for engineered EVs is critically discussed. For enhancing EV targeting and in vivo circulation time, the review highlights cutting-edge engineering solutions that may help overcome key obstacles in the clinical application of EV therapeutics. By presenting innovative concepts and strategies, this review aims to pave the way for the adaptation of DSC-EVs in regenerative medicine within clinical settings.