Delivery of melarsoprol using folate-targeted PEGylated cyclodextrin-based nanoparticles for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer, and has become one of the most lethal malignancies in the world. Although chemotherapy remains a cornerstone of cancer therapy, the number of chemotherapeutic drugs approved for HCC is low, and emerging therapeutics are needed. Melarsoprol (MEL) is an arsenic-containing drug, and has been applied in the treatment of human African trypanosomiasis at the late stage. In this study, the potential of MEL for HCC therapy was investigated for the first time using in vitro and in vivo experimental approaches. A folate-targeted polyethylene glycol-modified amphiphilic cyclodextrin nanoparticle was developed for safe, efficient and specific delivery of MEL. Consequently, the targeted nanoformulation achieved cell-specific uptake, cytotoxicity, apoptosis and migration inhibition in HCC cells. Furthermore, the targeted nanoformulation significantly prolonged the survival of mice with orthotopic tumor, without causing toxic signs. This study indicates the potential of the targeted nanoformulation as an emerging chemotherapy option for treating HCC.

Elabela-apelin-12, 17, 36/APJ system promotes platelet aggregation and thrombosis via activating the PANX1-P2X7 signaling pathway.

The elabela-apelin/angiotensin domain type 1 receptor-associated protein (APJ) system is an important regulator in certain thrombosis-related diseases such as atherosclerosis, myocardial infarction, and cerebral infarction. Our previous reports have revealed that apelin exacerbates atherosclerotic lesions. However, the relationship between the elabela-apelin/APJ system and platelet aggregation and atherothrombosis is unclear. The results of the present study demonstrate that elabela and other endogenous ligands such as apelin-12, -17, and -36 induce platelet aggregation and thrombosis by activating the pannexin1(PANX1)-P2X7 signaling pathway. Interestingly, the diuretic, spironolactone, a novel PANX1 inhibitor, alleviated elabela- and apelin isoforms-induced platelet aggregation and thrombosis. Significantly, two potential antithrombotic drugs were screened out by targeting APJ receptors, including the anti-HIV ancillary drug cobicistat and the traditional Chinese medicine monomer Schisandrin A. Both cobicistat and Schisandrin A abolished the effects of elabela and apelin isoforms on platelet aggregation, thrombosis, and cerebral infarction. In addition, cobicistat significantly attenuated thrombosis in a ponatinib-induced zebrafish trunk model. Overall, the elabela-apelin/APJ axis mediated platelet aggregation and thrombosis via the PANX1-P2X7 signaling pathway in vitro and in vivo. Blocking the APJ receptor with cobicistat/Schisandrin A or inhibiting PANX1 with spironolactone may provide novel therapeutic strategies against thrombosis.

The Precision Defect Engineering with Nonmetallic Element Refilling Strategy in g-C3 N4 for Enhanced Photocatalytic Hydrogen Production.

Traditional defect engineering and doping strategies are considered effective means for improving H2 evolution, but the uncontrollability of the modification process does not always lead to efficient activity. A defect-induced heteroatom refilling strategy is used here to synthesize heteroatoms introduced carbon nitride by precisely controlling the "introduction" sites on efficient N1 sites. Density functional theory calculations show that the refilling of B, P, and S sites have stronger H2 O adsorption and dissociation capacity than traditional doping, which makes it an optimal H2 production path. The large internal electric field strength of heteroatom-refilled catalysts leads to fast electron transfer and the hydrogen production of the best sample is up to 20.9 mmol g-1  h-1 . This work provides a reliable and clear insight into controlled defect engineering of photocatalysts and a universal modification strategy for typical heteroatom and co-catalyst systems for H2 production.

Targeting RNA Exonuclease XRN1 Potentiates Efficacy of Cancer Immunotherapy.

Despite the remarkable clinical responses achieved with immune checkpoint blockade therapy, the response rate is relatively low and only a subset of patients can benefit from the treatment. Aberrant RNA accumulation can mediate IFN signaling and stimulate an immune response, suggesting that targeting RNA decay machinery might sensitize tumor cells to immunotherapy. With this in mind, we identified an RNA exoribonuclease, XRN1, as a potential therapeutic target to suppress RNA decay and stimulate antitumor immunity. Silencing of XRN1 suppressed tumor growth in syngeneic immunocompetent mice and potentiated immunotherapy efficacy, while silencing of XRN1 alone did not affect tumor growth in immunodeficient mice. Mechanistically, XRN1 depletion activated IFN signaling and the viral defense pathway; both pathways play determinant roles in regulating immune evasion. Aberrant RNA-sensing signaling proteins (RIG-I/MAVS) mediated the expression of IFN genes, as depletion of each of them blunted the elevation of antiviral/IFN signaling in XRN1-silenced cells. Analysis of pan-cancer CRISPR-screening data indicated that IFN signaling triggered by XRN1 silencing is a common phenomenon, suggesting that the effect of XRN1 silencing may be extended to multiple types of cancers. Overall, XRN1 depletion triggers aberrant RNA-mediated IFN signaling, highlighting the importance of the aberrant RNA-sensing pathway in regulating immune responses. These findings provide the molecular rationale for developing XRN1 inhibitors and exploring their potential clinical application in combination with cancer immunotherapy. SIGNIFICANCE: Targeting XRN1 activates an intracellular innate immune response mediated by RNA-sensing signaling and potentiates cancer immunotherapy efficacy, suggesting inhibition of RNA decay machinery as a novel strategy for cancer treatment.

Exploiting the LSPR effect for an enhanced photocatalytic hydrogen evolution reaction.

Incorporation of plasmonic metals is one of the most widely adopted strategies for improving the photocatalytic hydrogen evolution reaction (HER) activity of semiconductor photocatalysts. This article summarizes recent advances in the development of plasmonic metal-semiconductor photocatalysts and four localized surface plasmon resonance (LSPR) driven mechanisms by which plasmonic metal nanoparticles can contribute to enhancement of HER activity. In addition, principles for maximizing the contribution of these LSPR driven mechanisms are highlighted to provide insights for future design of plasmonic metal-semiconductor photocatalysts with enhanced HER activity.

(Nano)platforms in bladder cancer therapy: Challenges and opportunities.

Urological cancers are among the most common malignancies around the world. In particular, bladder cancer severely threatens human health due to its aggressive and heterogeneous nature. Various therapeutic modalities have been considered for the treatment of bladder cancer although its prognosis remains unfavorable. It is perceived that treatment of bladder cancer depends on an interdisciplinary approach combining biology and engineering. The nanotechnological approaches have been introduced in the treatment of various cancers, especially bladder cancer. The current review aims to emphasize and highlight possible applications of nanomedicine in eradication of bladder tumor. Nanoparticles can improve efficacy of drugs in bladder cancer therapy through elevating their bioavailability. The potential of genetic tools such as siRNA and miRNA in gene expression regulation can be boosted using nanostructures by facilitating their internalization and accumulation at tumor sites and cells. Nanoparticles can provide photodynamic and photothermal therapy for ROS overgeneration and hyperthermia, respectively, in the suppression of bladder cancer. Furthermore, remodeling of tumor microenvironment and infiltration of immune cells for the purpose of immunotherapy are achieved through cargo-loaded nanocarriers. Nanocarriers are mainly internalized in bladder tumor cells by endocytosis, and proper design of smart nanoparticles such as pH-, redox-, and light-responsive nanocarriers is of importance for targeted tumor therapy. Bladder cancer biomarkers can be detected using nanoparticles for timely diagnosis of patients. Based on their accumulation at the tumor site, they can be employed for tumor imaging. The clinical translation and challenges are also covered in current review.

Filling the Gap between Heteroatom Doping and Edge Enrichment of 2D Electrocatalysts for Enhanced Hydrogen Evolution.

Composition modulation and edge enrichment are established protocols to steer the electronic structures and catalytic activities of two-dimensional (2D) materials. It is believed that a heteroatom enhances the catalytic performance by activating the chemically inert basal plane of 2D crystals. However, the edge and basal plane have inherently different electronic states, and how the dopants affect the edge activity remains ambiguous. Here we provide mechanistic insights into this issue by monitoring the hydrogen evolution reaction (HER) performance of phosphorus-doped MoS2 (P-MoS2) nanosheets via on-chip electrocatalytic microdevices. Upon phosphorus doping, MoS2 nanosheet gets catalytically activated and, more importantly, shows higher HER activity in the edge than the basal plane. In situ transport measurement demonstrates that the improved HER performance of P-MoS2 is derived from intrinsic catalytic activity rather than charge transfer. Density functional theory calculations manifest that the edge sites of P-MoS2 are energetically more favorable for HER. The finding guides the rational design of edge-dominant P-MoS2, reaching a minuscule onset potential of ∼30 mV and Tafel slope of 48 mV/dec that are benchmarked against other activation methods. Our results disclose the hitherto overlooked edge activity of 2D materials induced by heteroatom doping that will provide perspectives for preparing next-generation 2D catalysts.

On-Tissue Chemical Oxidation Followed by Derivatization for Mass Spectrometry Imaging Enables Visualization of Primary and Secondary Hydroxyl-Containing Metabolites in Biological Tissues.

On-tissue chemical derivatization combined with mass spectrometry imaging (MSI) can effectively visualize low-abundance and poorly ionizable molecules in biological tissues. Owing to the lack of an effective chemical reaction environment on the tissue surface, the development of direct one-step derivatization reactions is challenging. Herein, we present a two-step reaction involving on-tissue chemical oxidation followed by derivatization combined with airflow-assisted desorption electrospray ionization-MSI, enabling the visualization of primary and secondary hydroxyl-containing metabolites (PSHMs) within the tissue sections. This method indirectly achieved on-tissue derivatization by combining two reactions. Hydroxyl was converted to carbonyl using chemical oxidants, and subsequently, carbonyl was derived using Girard's P reagent. Using this methodology, 169 PSHMs, including hydroxy fatty acids (OH-FAs), fatty alcohols (FOHs), and sterol lipids, were detected and imaged in the tissues of rat brain, kidney, and liver. Moreover, we found that the abundant PSHMs, fatty aldehydes, and oxo fatty acids were significantly dysregulated in the liver and kidney tissues of type 2 diabetic rats; in particular, OH-FAs and FOHs were remarkably up-regulated in the diabetic rat liver tissues. The aberrations of these oxidative metabolites provide insights into the understanding of the molecular pathological mechanism of diabetes. This study demonstrates a novel, two-step reaction strategy for on-tissue derivatization with the analysis of previously inaccessible molecules using MSI.

FAM3C in circulating tumor-derived extracellular vesicles promotes non-small cell lung cancer growth in secondary sites.

Rationale: Metastasis is a complex process with a molecular underpinning that remains unclear. We hypothesize that cargo proteins conducted by extracellular vesicles (EVs) released from tumors may confer growth and metastasis potential on recipient cells. Here, we report that a cytokine-like secreted protein, FAM3C, contributes to late-stage lung tumor progression. Methods: EV protein profiling was conducted with an unbiased proteomic mass spectrometry analysis on non-small cell lung cancer (NSCLC) and normal lung fibroblast cell lines. Expression of FAM3C was confirmed in a panel of NSCLC cell lines, and correlated to the invasive and metastatic potentials. Functional phenotype of endogenous FAM3C and tumor-derived EVs (TDEs) were further investigated using various biological approaches in RNA and protein levels. Metastasis potential of TDEs secreted by FAM3C-overexpressing carcinoma cells was validated in mouse models. Results: Transcriptomic meta-analysis of pan-cancer datasets confirmed the overexpression of FAM3C - a gene encoding for interleukin-like EMT inducer (ILEI) - in NSCLC tumors, with strong association with poor patient prognosis and cancer metastasis. Aberrant expression of FAM3C in lung carcinoma cells enhances cellular transformation and promotes distant lung tumor colonization. In addition, higher FAM3C concentrations were detected in EVs extracted from plasma samples of NSCLC patients compared to those of healthy subjects. More importantly, we defined a hitherto-unknown mode of microenvironmental crosstalk involving FAM3C in EVs, whereby the delivery and uptake of FAM3C via TDEs enhances oncogenic signaling - in recipient cells that phenocopies the cell-endogenous overexpression of FAM3C. The oncogenicity transduced by FAM3C is executed via a novel interaction with the Ras-related protein RalA, triggering the downstream activation of the Src/Stat3 signaling cascade. Conclusions: Our study describes a novel mechanism for FAM3C-driven carcinogenesis and shed light on EV FAM3C as a driver for metastatic lung tumors that could be exploited for cancer therapeutics.

Efficient degradation of levofloxacin using a g-C3N4@glucose-derived carbon catalyst with adjustable N content via peroxymonosulfate activation.

Metal-free carbon-based catalysts hold great promise for the degradation of organic pollutants by peroxymonosulfate (PMS) activation because they avoid the negative effects of metal catalysts such as harmful metal ions leaching. However, these carbon-based catalysts are limited by their high cost and complex synthesis, and the mechanisms for the activation of PMS are unclear. Herein, the N-rich carbon catalysts (GCN-x) derived from glucose and g-C3N4 were facilely synthesized by hydrothermal treatment and carbonization to explore the mechanism of PMS activation. The nitrogen content of catalysts could be adjusted by simply altering the ratio of glucose and g-C3N4. GCN-2.4 with a ratio of glucose and g-C3N4 of 2.4 displayed the highest efficiency for the degradation of pollutants represented by Levofloxacin. The electron paramagnetic resonance and quenching experiments demonstrated that the non-radical pathway was dominant in Levofloxacin degradation and singlet oxygen (1O2) was the main active specie. Further, we found 1O2 was generated from superoxide radical (• O2-) which has rarely been studied. Levofloxacin degradation rate was shown to be positively correlated with both the amount of graphitic N and pyridinic N. Graphitic N and pyridinic N were identified as the catalytic sites. The GCN-2.4/PMS system could also remove multifarious contaminants effectively. Overall, this research advances understanding of the role of N species in PMS activation and has potential practical application in wastewater treatment.

Adjusting intervention strategies for mental health of COVID-19 patients: A network analysis based on a survey in Omicron-infected patients.

Background: The COVID-19 pandemic had a major impact on people's mental health. As the SAS-Cov-2 evolves to become less virulent, the number of asymptomatic patients increases. It remains unclear if the mild symptoms are associated with mild perceived stress and mental illness, and the interventions to improve the mental health of the patients are rarely reported. Methods: This cross-sectional study investigated the level of depression, anxiety and perceived stress of 1,305 COVID-19 patients who received treatment in the Fangcang shelter hospitals in Shanghai, China. Network analysis was used to explore the relationship among depression, anxiety and perceived stress. Results: The prevalence of depression, anxiety and perceived stress in the patients with Omicron infection were 9.03, 4.60, and 17.03%, respectively, lower than the prevalence reported during the initial outbreak of COVID-19. "Restlessness (A5)," "Uncontrollable worry (A2)," "Trouble relaxing (A4)" and "Fatigue (D4)" had the highest expected influence values. "Irritability (A6)" and "Uncontrollable (S1)" were bridge symptoms in the network. Comparative analysis of the network identified differences in the network structures between symptomatic and asymptomatic patients. Conclusion: This study investigated the prevalence of depression, anxiety and perceived stress and the correlation among them in Omicron-infected patients in Fangcang shelter hospital, in Shanghai, China. The core symptoms identified in the study provide insight into targeted clinical prevention and intervention of mental health in non-severe Omicron-infected patients.

Hypoxia signaling in hepatocellular carcinoma: Challenges and therapeutic opportunities.

Hepatocellular carcinoma (HCC) is one of the most common cancers with a relatively high cancer-related mortality. The uncontrolled proliferation of HCC consumes a significant amount of oxygen, causing the development of a hypoxic tumor microenvironment (TME). Hypoxia-inducible factors (HIFs), crucial regulators in the TME, activate several cancer hallmarks leading to the hepatocarcinogenesis of HCC and resistance to current therapeutics. As such, HIFs and their signaling pathways have been explored as potential therapeutic targets for the future management of HCC. This review discusses the current understanding of the structure and function of HIFs and their complex relationship with the various cancer hallmarks. To address tumor hypoxia, this review provides an insight into the various potential novel therapeutic agents for managing HCC, such as hypoxia-activated prodrugs, HIF inhibitors, nanomaterials, antisense oligonucleotides, and natural compounds, that target HIFs/hypoxic signaling pathways in HCC. Because of HCC's relatively high incidence and mortality rates in the past decades, greater efforts should be put in place to explore novel therapeutic approaches to improve the outcome for HCC patients.

Safety and short-term outcomes of laparoscopic surgery for advanced gastric cancer after neoadjuvant immunotherapy: A retrospective cohort study.

Background: Immune checkpoint inhibitors (ICIs) have been increasingly used for the treatment of advanced gastric cancer (AGC). However, the safety and the short-term outcomes of laparoscopic gastrectomy for patients with AGC after neoadjuvant immunotherapy (NAI) remain unknown. Methods: We retrospectively analyzed the patients with AGC who underwent laparoscopic surgery after neoadjuvant therapy between 1 January 2019 and 31 October 2021. We further compared the differences in postoperative complications, overall response rate, adverse events, surgical parameters, and postoperative recovery between two cohorts: the NAI group (NAI plus chemotherapy) and the neoadjuvant chemotherapy (NAC) group. Multivariable regression analyses were used to determine the risk factors for the overall response rate. Results: Overall, 80 patients were enrolled, of whom 30 cases were included in the NAI cohort and 50 were included in the NAC cohort. The overall rate of postoperative complications was 30.0% in both groups (p = 1.000). The overall response rate was 70.0% in the NAI cohort and 40% in the NAC cohort (p = 0.012). The adverse effects were found in 16 cases (53.3%) of the NAI cohort and 23 cases (46.0%) of the NAC cohort (p = 0.645). There was no statistical difference in intraoperative bleeding (50 ml vs. 50 ml, p = 0.983), operation time (320.9 min vs. 303.5 min, p = 0.382), dissected lymph node count (43.5 vs. 40.0, p = 0.364), first postoperative anal aerofluxus (3 days vs. 3 days, p = 0.091), first liquid diet (4 days vs. 5 days, p = 0.213), and postoperative length of stay in the hospital (8 days vs. 7 days, p = 0.508) between the two groups. NAI was estimated to be the independent protective factor [odds ratio (OR) 4.931, 95% confidence interval (CI) (1.385-17.559), p = 0.014] for odds to overall response rate, whereas vessel invasion was found to be the significant risk factor [OR 0.113, 95% CI (0.027-0.475), p = 0.003]. Conclusions: Laparoscopic surgery after NAI combined with chemotherapy is a safe therapeutic choice for AGC and may bring better short-term outcomes due to a higher overall response rate.

High spin Fe3+-related bonding strength and electron transfer for sensitive and stable SERS detection.

The intrinsic electronic states of transition metal-containing SERS substrates, especially the effect of spin state on the detection sensitivity, still remain unknown. Herein, we propose a simple co-precipitation approach to form trimetallic MIL-101(FeNiTi) with high-spin (HS) Fe3+ as a result of geometric distortion of the octahedral symmetry. Using methylene blue as a demonstration, the trimetallic MIL-101(FeNiTi) shows a high enhancement factor (EF) of 6.1 × 106, a low detection limit of 10-9 M and excellent detection stability after long-term preservation. X-ray absorption fine structure and photoelectron spectra demonstrate that coupling between high-spin Fe3+ and aliovalent transition metals Ni2+ and Ti4+ with different filling degree of 3d eg-orbitals results in electron delocalization. The DFT calculation suggests that MIL-101(FeNiTi) with high-spin Fe3+ favors molecular adsorption and the charge transfer from the molecule to MIL-101(FeNiTi) is promoted, benefitting from the enhanced electron delocalization, which both contribute to the distinguished SERS performance of MIL-101(FeNiTi). This finding provides in-depth mechanistic understanding of the effect of the spin state of transition metals on mediating SERS activity, which is expected to efficiently promote the development of SERS platforms based on non-noble metals.

Non-Coding RNAs of Extracellular Vesicles: Key Players in Organ-Specific Metastasis and Clinical Implications.

Extracellular vesicles (EVs) are heterogeneous membrane-encapsulated vesicles released by most cells. They act as multifunctional regulators of intercellular communication by delivering bioactive molecules, including non-coding RNAs (ncRNAs). Metastasis is a major cause of cancer-related death. Most cancer cells disseminate and colonize a specific target organ via EVs, a process known as "organ-specific metastasis". Mounting evidence has shown that EVs are enriched with ncRNAs, and various EV-ncRNAs derived from tumor cells influence organ-specific metastasis via different mechanisms. Due to the tissue-specific expression of EV-ncRNAs, they could be used as potential biomarkers and therapeutic targets for the treatment of tumor metastasis in various types of cancer. In this review, we have discussed the underlying mechanisms of EV-delivered ncRNAs in the most common organ-specific metastases of liver, bone, lung, brain, and lymph nodes. Moreover, we summarize the potential clinical applications of EV-ncRNAs in organ-specific metastasis to fill the gap between benches and bedsides.

Postoperative anion gap associates with short- and long-term mortality after cardiac surgery: A large-scale cohort study.

Objective: To investigate whether postoperative anion gap (AG) is associated with short- and long-term mortality in patients following cardiac surgery. Materials and methods: We conducted a retrospective cohort study of adults who underwent cardiac surgery from the Medical Information Mart for Intensive Care - III database. The generalized additive model (GAM), logistic regression, and Cox regression were performed to assess the correlations between AG levels and in-hospital, 90-day, and 4-year mortality. Linear regression was used to evaluate the associations between AG and length of stay (LOS). Results: Totally, 6,410 subjects were enrolled in this study and classified into tertiles based on the initial AG levels. The GAM indicated a positive association between initial AG and in-hospital mortality after adjusting for potential confounders. Multivariate logistic analysis revealed that the risk of in-hospital mortality was higher among patients in tertile 2 (OR 2.05, 95% CI 1.11-3.76, P = 0.021) and tertile 3 (OR 4.51, 95% CI 2.57-7.91, P < 0.001) compared with those in tertile 1. For 90-day and 4-year mortality, multivariate Cox regression found similar associations between AG tertiles and mortality. The LOS in ICU and hospital also increased as AG tertiles increased. The E-value indicated robustness to unmeasured confounders. Conclusion: This study found a positive association between postoperative AG levels and short- and long-term mortality among patients after cardiac surgery. This relationship warrants further research.

The Relationship between Physical Exercise and Negative Emotions in College Students in the Post-Epidemic Era: The Mediating Role of Emotion Regulation Self-Efficacy.

OBJECTIVE: To investigate the relationship between physical activity and negative emotions among college students in the post-epidemic era and determine if emotional regulation plays a mediating role between physical activity and negative emotions. METHODS: 479 college students (293 males, 186 females, M = 19.94, SD = 1.25) who were under closed campus management during the epidemic period were surveyed using the physical activity rating scale (PARS-3), the self-assessment scale for anxiety (SAS), the self-esteem scale for depression (SDS), and the emotion regulation self-efficacy scale (RES). RESULTS: (1) Physical activity, negative emotions, and emotion regulation self-efficacy among college students were significantly different by gender (p < 0.01). (2) Physical exercise was negatively correlated with anxiety and depression (r = -0.236, p < 0.01; r = -0.198, p < 0.01) and positively correlated with emotion regulation self-efficacy (r = 0.256, p < 0.01) in college students. (3) Emotion regulation self-efficacy was negatively correlated with anxiety and depression (r = -0.440, p < 0.01; r = -0.163, p < 0.01). (4) Emotion regulation self-efficacy also partially mediated the relationship between physical activity and negative emotions. CONCLUSION: (1) Physical activity in the post-epidemic era negatively predicted anxiety and depression in school-isolated college students. (2) Emotion regulation self-efficacy in the post-epidemic era partially mediates the relationship between physical activity and anxiety and depression.

Wnt/ß-catenin signaling pathway is activated in the progress of mandibular condylar cartilage degeneration and subchondral bone loss induced by overloaded functional orthopedic force (OFOF).

Objective: To explore the role of Wnt/ß-catenin signaling pathway in the pathogenesis and progression of temporomandibular joint osteoarthritis (TMJ OA) caused by overloaded force. Materials and methods: We generated a rat model of forward mandibular extension device to induce TMJ OA by overloaded force. Condylar cartilage samples were collected at 2wk, 4wk, and 8wk after appliances were installed. Changes of the condylar cartilage and subchondral bone were evaluated by hematoxylin and eosin (HE), Safranin O and Fast Green staining (SO&FG), micro-CT, tartrate resistant acid phosphatase (TRAP) staining. The expression levels of ß-catenin, COL-2, MMP3 and sclerostin (SOST) were detected by immunohistochemistry (IHC) and PCR. Results: HE, SO&FG, micro-CT, OARSI and Mankin scores showed that the condyle cartilage layer was significantly thinner and proteoglycan loss in the overloded group. TRAP staining exhibited that the number of positive osteoclasts increased and OPG level decreased in the overload group. IHC, PCR showed that the expression of COL2 and SOST decreased, while MMP3 and ß-catenin increased in the overload group. Conclusion: Wnt/ß-catenin signaling pathway is activated in the progress of mandibular condylar cartilage degeneration and subchondral bone loss induced by overloaded functional orthopedic force (OFOF).

On-Chip Investigation of Electrocatalytic Oxygen Reduction Reaction of 2D Materials.

The on-chip electrocatalytic microdevice (OCEM) is an emerging platform specialized in the electrochemical investigation of single-entity nanomaterials, which is ideal for probing the intrinsic catalytic properties, optimizing performance, and exploring exotic mechanisms. However, the current catalytic applications of OCEMs are almost exclusively in electrocatalytic hydrogen/oxygen evolution reactions with minimized influence from the mass transfer. Here, an OCEM platform specially tailored to investigate the electrocatalytic oxygen reduction reaction (ORR) at a microscopic level by introducing electrolyte convection through a microfluidic flow cell is reported. The setup is established on gold microelectrodes and later successfully applied to investigate how Ar-plasma treatment affects the ORR activities of 2H MoS2 . This study finds that Ar-plasma treatment significantly enhances the ORR performance of MoS2 nanosheets owing to the introduction of surface defects. This study paves the way for highly efficient microscopic investigation of diffusion-controlled electrocatalytic reactions.

All-Optical Modulation of Single Defects in Nanodiamonds: Revealing Rotational and Translational Motions in Cell Traction Force Fields.

Measuring the mechanical interplay between cells and their surrounding microenvironment is vital in cell biology and disease diagnosis. Most current methods can only capture the translational motion of fiduciary markers in the deformed matrix, but their rotational motions are normally ignored. Here, by utilizing single nitrogen-vacancy (NV) centers in nanodiamonds (NDs) as fluorescent markers, we propose a linear polarization modulation (LPM) method to monitor in-plane rotational and translational motions of the substrate caused by cell traction forces. Specifically, precise orientation measurement and localization with background suppression were achieved via optical polarization selective excitation of single NV centers with precisions of ∼0.5°/7.5 s and 2 nm/min, respectively. Additionally, we successfully applied this method to monitor the multidimensional movements of NDs attached to the vicinity of cell focal adhesions. The experimental results agreed well with our theoretical calculations, demonstrating the practicability of the NV-based LPM method in studying mechanobiology and cell-material interactions.