Regulation of photosynthetic function and reactive oxygen species metabolism in sugar beet (Beta vulgaris L.) cultivars under waterlogging stress and associated tolerance mechanisms.

Sugar beet (Beta vulgaris L.) is an economically important sugar crop worldwide that is susceptible to sudden waterlogging stress during seedling cultivation, which poses a major threat to sugar beet development and production. Our understanding of the physiological basis of waterlogging tolerance in sugar beet is limited. To investigate the photosynthetic adaptation strategies of sugar beet to waterlogging stress conditions, the tolerant cultivar KUHN1260 (KU) and sensitive cultivar SV1433 (SV) were grown under waterlogging stress, and their photosynthetic function and reactive oxygen species (ROS) metabolism were assessed. Our results showed that waterlogging stress significantly reduced the photosynthetic pigment content, rubisco activity, and expression level of the photosynthetic enzyme genes SvRuBP, SvGAPDH, and SvPRK, gas exchange parameters, and chlorophyll fluorescence parameters, induced damage to the ultrastructure of the chloroplast of the two sugar beet cultivars, inhibited the photosynthetic carbon assimilation capacity of sugar beet leaves, damaged the structural stability of photosystem II (PSII), and disturbed the equilibrium between electrons at the acceptor and donor sides of PSII, which was the result of stomatal and non-stomatal limiting factors. Moreover, the level of ROS, H2O2, and O2▪-, antioxidant enzyme activity, and gene expression levels in the leaves of the two sugar beet cultivars increased over time under waterlogging stress; ROS accumulation was lower and antioxidant enzyme activities and gene expression levels were higher in the waterlogging-tolerant cultivar (KU) than the waterlogging-sensitive cultivar (SV). In sum, these responses in the more tolerant cultivars are associated with their resistance to waterlogging stress. Our findings will aid the breeding of waterlogging-tolerant sugar beet cultivars.

A novel endoscopic nasopharyngectomy by low-temperature plasma radiofrequency ablation in localized recurrent nasopharyngeal carcinoma.

OBJECTIVE: Endoscopic nasopharyngectomy (ENPG) with en bloc resection has been well accepted in resectable localized recurrent nasopharyngeal carcinoma (rNPC), but it is a difficult technique to master for most otorhinolaryngology head and neck surgeons. Ablation surgery is a new and simplified method to remove tumors. We designed a novel method using low-temperature plasma radiofrequency ablation (LPRA) and evaluated the survival benefit. METHODS: A total of 56 localized rNPC patients were explained in detail and retrospectively analyzed. The surgery method was ablated from the resection margin to the center of the tumor. The postmetastatic overall survival (OS), local relapse-free survival (LRFS) rate, progression-free survival (PFS) and distant metastasis-free survival (DMFS) were analyzed using the Kaplan-Meier method and compared by the log-rank test. RESULTS: All surgeries were successfully performed without any severe postoperative complications or deaths. The median operation time of ablation and harvested NSFF respectively were 29 min (range, 15-100 min) and 101 min (range, 30-180 min). The average number of hospital days postoperation was 3 days (range, 2-5 days). All cases (100.0%) had radical ablation with negative resection margins. The nasopharyngeal defects were completely re-epithelialized in 54 (96.4%) patients. As of the data cutoff (September 3, 2023), the median follow-up time was 44.3 months (range, 17.1-52.7 months, 95% CI: 40.4-48.2). The 3-year OS, LRFS, PFS and DMFS of the entire cohort were 92.9% (95% CI: 0.862-0.996), 89.3% (95% CI: 0.813-0.973), 87.5% (95% CI: 0.789-0.961), and 92.9% (95% CI: 0.862-0.996), respectively. Cycles of radiotherapy were independent risk factors for OS (p = 0.003; HR, 32.041; 95% CI: 3.365-305.064), LRFS (p = 0.002; HR, 10.762; 95% CI: 2.440-47.459), PFS (p = 0.004; HR, 7.457; 95% CI: 1.925-28.877), and DMFS (p = 0.002; HR, 34.776; 95% CI: 3.806-317.799). CONCLUSION: Radical endoscopic nasopharyngectomy by using low-temperature plasma radiofrequency ablation is a novel, safe and simplified method to master and disseminate for treating resectable rNPC. However, further data and longer follow-up time are needed to prove its efficacy.

Assessment of Prophylactic Internal Carotid Artery Management in Postradiation Nasopharyngeal Necrosis Patients.

OBJECTIVE: Postradiation nasopharyngeal necrosis (PRNN) frequently develops after second-course radiotherapy for nasopharyngeal carcinoma (NPC). PRNN can lead to internal carotid artery (ICA) massive hemorrhage due to ICA rupture, resulting in sudden death. This study aims to explore the pretreatment of the ICA to prevent fatal massive hemorrhage in PRNN patients. STUDY DESIGN: Retrospective cohort study. SETTING: Sun Yat-sen University Cancer Center. METHODS: Patients diagnosed with NPC and PRNN from January 2010 to September 2022 were included. The Cox proportional hazards regression analysis was performed to analyze risk factors for massive hemorrhage and survival. A nomogram was developed to integrate prognostic models and perform parameter calibration. RESULTS: Two hundred and fifty-four PRNN patients were included in this study. Prophylactic ICA occlusion significantly reduced the risk of ICA hemorrhage compared to no prophylactic ICA occlusion (3.6% vs 40.6%, P < .001). Surgical repair on necrosis significantly prevented hemorrhage and improved survival. The nomogram, incorporating the above 2 factors and the nearest distance from necrosis to ICA ≤ 3 mm, exhibited excellent discriminative ability for hemorrhage. We identified 3 high-risk factors that indicate the need for prophylactic ICA management in PRNN patients: (1) exposure of ICA by rhinoscopy; (2) signs of ICA erosion on MRA scanning; (3) the depth of soft tissue coverage surrounding the ICA wall within the necrotic cavity is less than 3 mm on magnetic resonance imaging. CONCLUSION: We have identified 3 high-risk factors for PRNN patients that necessitate prophylactic ICA management. These findings are expected to contribute to improving the quality of life and overall survival of PRNN patients.

Camrelizumab plus famitinib in patients with recurrent or metastatic nasopharyngeal carcinoma treated with PD-1 blockade: data from a multicohort phase 2 study.

Background: Treatment options for patients with recurrent/metastatic nasopharyngeal carcinoma (RM-NPC) are not clear after progression on previous treatment with PD-(L)1 inhibitor; critical gaps in evidence remain for such cases. Immunotherapy combined with antiangiogenic therapy has been reported to have synergistic antitumor activity. Therefore, we evaluated the efficacy and safety of camrelizumab plus famitinib in patients with RM-NPC who failed treatment with PD-1 inhibitor-containing regimens. Methods: This multicenter, adaptive Simon minimax two-stage, phase II study enrolled patients with RM-NPC refractory to at least one line of systemic platinum-containing chemotherapy and anti-PD-(L)1 immunotherapy. The patient received camrelizumab 200 mg every 3 weeks and famitinib 20 mg once per day. The primary endpoint was objective response rate (ORR), and the study could be stopped early as criterion for efficacy was met (>5 responses). Key secondary endpoints included time to response (TTR), disease control rate (DCR), progression-free survival (PFS), duration of response (DoR), overall survival (OS), and safety. This trial was registered with ClinicalTrials.gov, NCT04346381. Findings: Between October 12, 2020, and December 6, 2021, a total of 18 patients were enrolled since six responses were observed. The ORR was 33.3% (90% CI, 15.6-55.4) and the DCR was 77.8% (90% CI, 56.1-92.0). The median TTR was 2.1 months, the median DoR was 4.2 months (90% CI, 3.0-not reach), and the median PFS was 7.2 months (90% CI, 4.4-13.3), with a median follow-up duration of 16.7 months. Treatment-related adverse events (TRAEs) of grade ≥3 were reported in eight (44.4%) patients, with the most common being decreased platelet count and/or neutropenia (n = 4, 22.2%). Treatment-related serious AEs occurred in six (33.3%) patients, and no deaths occurred due to TRAEs. Four patients developed grade ≥3 nasopharyngeal necrosis; two of them developed grade 3-4 major epistaxis, and they were cured by nasal packing and vascular embolization. Interpretation: Camrelizumab plus famitinib exhibited encouraging efficacy and tolerable safety profiles in patients with RM-NPC who failed frontline immunotherapy. Further studies are needed to confirm and expand these findings. Funding: Jiangsu Hengrui Pharmaceutical Co., Ltd.

Fosaprepitant Weekly vs Every 3 Weeks for the Prevention of Concurrent Chemoradiotherapy-Induced Nausea and Vomiting: A Pilot Randomized Clinical Trial.

Importance: Unlike substantial evidence in the prevention of chemotherapy-induced nausea and vomiting (CINV), research in the prevention of nausea and vomiting caused by concurrent chemoradiotherapy (CCRT) is currently lacking. Objective: To compare the efficacy and safety of fosaprepitant weekly vs every 3 weeks for the prevention of nausea and emesis caused by CCRT among patients with nasopharyngeal carcinoma. Design, Setting, and Participants: This pilot randomized clinical trial was conducted at a single cancer center from November 24, 2020, to July 26, 2021, among patients with nasopharyngeal carcinoma who had achieved CINV control after 2 to 3 cycles of induction chemotherapy. Efficacy analyses were performed in the intention-to-treat population. Data were analyzed on November 4, 2022. Interventions: Eligible patients were randomly assigned (1:1) to receive fosaprepitant either weekly or every 3 weeks. Main Outcomes and Measures: The primary end point was the proportion of patients with sustained complete response (defined as no emesis and no rescue therapy) during CCRT. Secondary end points were sustained no emesis, no nausea, no significant nausea, mean time to first emetic episode, quality of life, and 1-year progression-free survival (PFS). Results: A total of 100 patients (mean [SD] age, 46.6 [10.9] years; 83 [83.0%] male) who had achieved CINV control after induction chemotherapy were randomly assigned to receive fosaprepitant weekly (50 patients) or every 3 weeks (50 patients). There was no significantly significant difference in cumulative risk of emesis or rescue therapy in the group that received weekly fosaprepitant compared with those who received fosaprepitant every 3 weeks (subhazard ratio, 0.66 [95% CI, 0.43-1.02]; P = .06). The proportion of patients with sustained no emesis (38% vs 14%; P = .003) or no significant nausea (92% vs 72%; P = .002) was significantly higher in the group that received fosaprepitant weekly vs those who received fosaprepitant every 3 weeks. Treatments were well tolerated. Patients in the weekly group had improved scores for multiple quality-of-life measures. There was no significant difference in survival outcomes between groups (91.8% vs 93.7%; P = .99). In the mean brainstem dose subgroups, a possible treatment interaction effect was observed in sustained complete response (mean brainstem dose ≥36 Gy: hazard ratio [HR], 0.32 [95% CI, 0.15-0.69]; mean brainstem dose <36 Gy: HR, 0.95 [95% CI, 0.55-1.63]) and sustained no emesis (mean brainstem dose ≥36 Gy: HR, 0.21 [95% CI, 0.08-0.53]; mean brainstem dose <36 Gy: HR, 0.73 [95% CI, 0.41-1.28]). Conclusions and Relevance: In this pilot randomized clinical trial, there was no statistically significant difference in the complete response primary end point, but patients receiving weekly fosaprepitant were less likely to experience emesis compared with those who received fosaprepitant every 3 weeks, especially in the subgroup with a mean brainstem dose of 36 Gy or more. Weekly fosaprepitant was well tolerated and improved quality of life of patients without compromising survival. Trial Registration: ClinicalTrials.gov Identifier: NCT04636632.

Waterlogging stress alters the structure of sugar beet rhizosphere microbial community structure and recruiting potentially beneficial bacterial.

Waterlogging has been shown to have a significant inhibitory effect on plant growth. However, the response mechanisms of the soil environment of sugar beet seedlings under waterlogging conditions still need to be fully understood. This study aimed to investigate the effects of waterlogging treatments on the content of effective nutrients and the microbial communities in the rhizosphere and non-rhizosphere using high-throughput sequencing. We set up waterlogging and non-waterlogging treatments, sampled sugar beet seedlings after 10 days of waterlogging, determined the effective soil nutrients in the rhizosphere and non-rhizosphere of the plants, and analyzed the differences in microbial diversity at ten days of waterlogging. The results showed that waterlogging significantly affected available potassium (AK) content. The Ak content of waterlogged soil was significantly higher than that of non-waterlogged soil. Waterlogging caused no significant difference in available nitrogen (AN) content and pH. Moreover, the plant growth-promoting bacteria Pseudomonas was significantly enriched in sugar beet waterlogged rhizospheres compared with the non-waterlogged ones. Similarly, the harmful fungi Gibellulopsis and Alternaria were enriched in sugar beet non-waterlogged rhizosphere. The network analysis revealed that waterlogging built a less complex root-microbial network than non-waterlogging. These findings implied that sugar beets subjected to waterlogging stress were enriched with beneficial microorganisms in the rhizosphere, potentially alleviating the stress.

Camrelizumab Plus Apatinib in Patients With Recurrent or Metastatic Nasopharyngeal Carcinoma: An Open-Label, Single-Arm, Phase II Study.

PURPOSE: Immune checkpoint inhibitors combined with antiangiogenic therapy reportedly have potential synergistic antitumor activity. We investigated the activity and safety of this regimen for recurrent/metastatic nasopharyngeal carcinoma (NPC). METHODS: This single-arm, Simon two-stage study enrolled patients with recurrent/metastatic NPC who were refractory to at least first-line systemic therapy and treatment-naive to immune checkpoint inhibitors. The patients received camrelizumab 200 mg once every 3 weeks and apatinib 250 mg once per day. The primary end point was the objective response rate. Key secondary end points included disease control rate, progression-free survival, duration of response, overall survival, and safety. RESULTS: Between October 14, 2020, and December 23, 2021, 58 patients were enrolled, and all were included in the efficacy and safety analysis set. The objective response rate was 65.5% (95% CI, 51.9 to 77.5), and the disease control rate was 86.2% (95% CI, 74.6 to 93.9). The median duration of response was not reached, and the median progression-free survival was 10.4 months (95% CI, 7.2 to 13.6), with a median follow-up duration of 12.4 months (range, 2.1-19.9 months). Treatment-related adverse events (TRAEs) of grade 3 or higher were reported in 34 (58.6%) patients, with the most common being hypertension (19.0%), nasopharyngeal necrosis (15.5%), headache (12.1%), AST elevation (10.3%), and creatine phosphokinase elevation (10.3%). Sixteen (27.6%) patients discontinued apatinib treatment before progression because of unbearable TRAEs, and the most common complication was nasopharyngeal necrosis (9/16; 56.3%). Recurrent nasopharyngeal lesions (odds ratio, 5.94 [95% CI, 1.45 to 24.24]) and reirradiation (odds ratio, 5.33 [95% CI, 1.15 to 24.79]) were significantly positively correlated with nasopharyngeal necrosis. CONCLUSION: Camrelizumab plus apatinib had promising antitumor activity in patients with refractory recurrent/metastatic NPC who failed first-line therapy. Moderate to severe TRAEs were experienced by 58.6%, including nasopharyngeal necrosis associated with local recurrence and a history of reirradiation.

Hyperfractionation compared with standard fractionation in intensity-modulated radiotherapy for patients with locally advanced recurrent nasopharyngeal carcinoma: a multicentre, randomised, open-label, phase 3 trial.

BACKGROUND: Reirradiation in standard fractionation for locally advanced recurrent nasopharyngeal carcinoma after a previous course of high-dose radiotherapy is often associated with substantial late toxicity, negating its overall benefit. We therefore aimed to investigate the efficacy and safety of hyperfractionation compared with standard fractionation in intensity-modulated radiotherapy. METHODS: This multicentre, randomised, open-label, phase 3 trial was done in three centres in Guangzhou, China. Eligible patients were aged 18-65 years with histopathologically confirmed undifferentiated or differentiated, non-keratinising, advanced locally recurrent nasopharyngeal carcinoma. Participants were randomly assigned (1:1) to either receive hyperfractionation (65 Gy in 54 fractions, given twice daily with an interfractional time interval of at least 6 h) or standard fractionation (60 Gy in 27 fractions, given once a day). Intensity-modulated radiotherapy was used in both groups. A computer program generated the assignment sequence and randomisation was stratified by treatment centre, recurrent tumour stage (T2-T3 vs T4), and recurrent nodal stage (N0 vs N1-N2), determined at the time of randomisation. The two primary endpoints were the incidence of severe late complications defined as the incidence of grade 3 or worse late radiation-induced complications occurring 3 months after the completion of radiotherapy until the latest follow-up in the safety population, and overall survival defined as the time interval from randomisation to death due to any cause in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02456506. FINDINGS: Between July 10, 2015, and Dec 23, 2019, 178 patients were screened for eligibility, 144 of whom were enrolled and randomly assigned to hyperfractionation or standard fractionation (n=72 in each group). 35 (24%) participants were women and 109 (76%) were men. After a median follow-up of 45·0 months (IQR 37·3-53·3), there was a significantly lower incidence of grade 3 or worse late radiation-induced toxicity in the hyperfractionation group (23 [34%] of 68 patients) versus the standard fractionation group (39 [57%] of 68 patients; between-group difference -23% [95% CI -39 to -7]; p=0·023). Patients in the hyperfractionation group had better 3-year overall survival than those in the standard fractionation group (74·6% [95% CI 64·4 to 84·8] vs 55·0% [43·4 to 66·6]; hazard ratio for death 0·54 [95% CI 0·33 to 0·88]; p=0·014). There were fewer grade 5 late complications in the hyperfractionation group (five [7%] nasal haemorrhage) than in the standard fractionation group (16 [24%], including two [3%] nasopharyngeal necrosis, 11 [16%] nasal haemorrhage, and three [4%] temporal lobe necrosis). INTERPRETATION: Hyperfractionated intensity-modulated radiotherapy could significantly decrease the rate of severe late complications and improve overall survival among patients with locally advanced recurrent nasopharyngeal carcinoma. Our findings suggest that hyperfractionated intensity-modulated radiotherapy could be used as the standard of care for these patients. FUNDING: Key-Area Research and Development of Guangdong Province, the National Natural Science Foundation of China, the Special Support Program for High-level Talents in Sun Yat-sen University Cancer Center, the Guangzhou Science and Technology Plan Project, and the National Ten Thousand Talents Program Science and Technology Innovation Leading Talents, Sun Yat-Sen University Clinical Research 5010 Program.

Gemcitabine combined with apatinib and toripalimab in recurrent or metastatic nasopharyngeal carcinoma.

BACKGROUND: The role of a triple combination of gemcitabine (chemotherapy) plus apatinib (anti-vascular endothelial growth factor [VEGFR]) and toripalimab (anti-PD-1) (GAT) in recurrent/metastatic nasopharyngeal carcinoma (RM-NPC) is unclear. METHODS: Between August 2019 and April 2020, 41 patients with RM-NPC were enrolled and received GAT for up to 6 cycles followed by apatinib and toripalimab. The primary endpoint was the safety. The secondary endpoints included the objective response rate (ORR) and progression-free survival (PFS). Integrated genomic and transcriptional analyses were conducted to identify the patients who benefited in response to this novel combination therapy. FINDINGS: As of April 1, 2022, treatment-related grade 3 or 4 adverse events (AEs) occurred in 23 of 41 patients (56.1%, 95% confidence interval [CI] 41%-70.1%). G3-4 nasopharyngeal necrosis was observed in 9 (9/41, 21.9%) patients. High-risk factors for necrosis included repeated radiotherapy and an interval of less than 12 months from the last radiotherapy. The ORR was 90.2% (95% CI: 76.9%-97.2%). The median PFS was 25.8 months (95% CI: not reached (NR)-NR), and the 24-month PFS rate was 50.7% (95% CI: 34.0%-67.4%). MAS-related GPR family member F (MRGPRF) high expression in tumors correlated with poor PFS from the GAT therapy, characterized by high epithelial mesenchymal transition signatures. Serial circulating tumor DNA (ctDNA) sequencing could predict PFS outcomes to combination therapy. CONCLUSIONS: GAT therapy exhibits a promising antitumor activity and manageable toxicities in patients with RM-NPC. Patients with repeated radiotherapy and an interval of less than 12 months from the last radiotherapy should be carefully selected for antiangiogenic therapies. MRGPRF expression and serial ctDNA monitoring could identify patients that derive benefits from the combination therapy. TRIAL REGISTRATION: ClinicalTrials.gov: NCT04073784. FUNDING: This research was funded by the National Natural Science Foundation of China (nos. 81772895 and 82002857), the Key-Area Research and Development of Guangdong Province (2020B1111190001), the Special Support Program for High-level Talents in Sun Yat-sen University Cancer Center, the Guangzhou Science and Technology Plan Project (202103010001), and the National "Ten Thousand Talents Program" Science and Technology Innovation Leading Talents (84000-41180005).

Efficacy of local therapy to metastatic foci in nasopharyngeal carcinoma: large-cohort strictly-matched retrospective study.

Background: Studies of local therapy (LT) to metastatic foci from nasopharyngeal carcinoma (NPC) are inconsistent and controversial. Here, we aimed to explore the survival benefit of LT directed at metastatic foci from NPC. Methods: A retrospective analysis was conducted in NPC patients with liver, lung, and/or bone metastases. The postmetastatic overall survival (OS) rate was analyzed using the Kaplan-Meier method and compared by the log-rank test. Multivariate analysis was performed using the Cox hazard model. Subgroup analyses evaluating the effect of LT were performed for prespecified covariates. Propensity score matching was applied to homogenize the compared arms. Results: Overall, 2041 of 2962 patients were eligible for analysis. At a median follow-up of 43.4 months, the 5-year OS improved by an absolute difference of 14.6%, from 46.2% in the LT group versus 31.6% in the non-LT group, which led to a hazard ratio of 0.634 for death (p < 0.001). Matched-pair analyses confirmed that LT was associated with improved OS (p = 0.003), and the survival benefits of LT remained consistent in the subcohorts of liver and lung metastasis (p = 0.009 and p = 0.007, respectively) but not of bone metastasis (BoM; p = 0.614). Radiotherapy was predominantly used for BoM and biological effective dose (BED) >60 Gy was found to yield more survival benefit than that of BED ⩽ 60 Gy. Conclusions: The addition of LT directed at metastasis has demonstrated an improvement to OS compared with non-LT group in the present matched-pair study, especially for patients with liver and/or lung metastases.

Toripalimab plus intensity-modulated radiotherapy for recurrent nasopharyngeal carcinoma: an open-label single-arm, phase II trial.

BACKGROUND: Toripalimab is a humanized immunoglobulin G4 monoclonal antibody against programmed death 1. We aimed to investigate the efficacy and safety of toripalimab in combination with intensity-modulated radiotherapy (IMRT) for recurrent nasopharyngeal carcinoma (rNPC). METHODS: We conducted a single-arm, phase II trial with patients with rNPC who had biopsy-proven disease and were unsuitable for local surgery. Eligible patients received IMRT in combination with toripalimab administered via intravenous infusion of 240 mg once every 3 weeks for a maximum of seven cycles. The primary endpoint was the objective response rate at 3 months post radiotherapy. The secondary endpoints included safety profiles, progression-free survival (PFS). RESULTS: Between May 2019 and January 2020, a total of 25 patients with rNPC were enrolled (18 men (72.0%) and 7 women (28.0%); median (IQR) age, 49.0 (43.5-52.5) years). With a median (IQR) follow-up duration of 14.6 months (13.1-16.2) months, 19 patients (79.2%) achieved an overall response, and disease control was achieved in 23 (95.8%) patients at 3 months post radiotherapy. The 12-month PFS was 91.8% (95% CI 91.7% to 91.9%). The incidences of acute (grade ≥3) blood triglyceride elevation, creatine kinase elevation, skin reaction, and mucositis were 1 (4.0%), 1 (4.0%), 2 (8.0%), and 1 (4.0%), respectively. The incidences of late severe (grade ≥3) nasopharyngeal wall necrosis, nasal bleeding, and trismus were 28.0%, 12.0%, and 4.0%, respectively. CONCLUSIONS: Toripalimab combined with IMRT was tolerable and showed promising antitumor activity in patients with rNPC. TRIAL REGISTRATION NUMBER: NCT03854838.

Microinjection of valproic acid into the ventrolateral orbital cortex exerts an antinociceptive effect in a rat of neuropathic pain.

RATIONALE: Ventrolateral orbital cortex (VLO) has been found to play an important role in the regulation of neuropathic pain (NPP). As a traditional mood stabilizer, valproic acid (VPA) is currently employed in the treatment of NPP. However, whether VPA plays an analgesic role in VLO is still unknown. OBJECTIVES: To elucidate the underlying analgesic mechanism of microinjection of VPA into the VLO on spared nerve injury (SNI), an animal model of NPP. METHODS: We firstly examined the role of VPA by intraperitoneal and intral-VLO injection. Then, we accessed its role as a histone deacetylase inhibitor by intral-VLO microinjection of sodium butyrate. Finally, the GABAergic mechanism was measured through the intra-VLO microinjection of several agonists and antagonists of various GABAergic receptor subtypes. RESULTS: Both intraperitoneal and intral-VLO injection of VPA attenuated SNI-induced mechanical allodynia. Microinjection of sodium butyrate, one of the histone deacetylase inhibitors, into the VLO attenuated the mechanical allodynia. Besides, microinjection of valpromide, a derivative of VPA which is a GABAergic agonist, into the VLO also attenuated allodynia. Furthermore, microinjection of picrotoxin, a GABAA receptor antagonist, into the VLO attenuated mechanical allodynia; microinjection of picrotoxin before VPA into the VLO increased VPA-induced anti-allodynia. Besides, microinjection of CGP 35348, a GABAB receptor antagonist, into the VLO attenuated allodynia; microinjection of CGP 35348 before VPA into the VLO also increased VPA-induced anti-allodynia. What is more, microinjection of imidazole-4-acetic acid (I4AA), a GABAC receptor antagonist, into the VLO enhanced allodynia; microinjection of I4AA before VPA into the VLO decreased VPA-induced anti-allodynia. CONCLUSIONS: These results suggest that both the histone acetylation mechanism and GABAergic system are involved in mediating VLO-induced anti-hypersensitivity.

Magnetic Enhancement of Chondrogenic Differentiation of Mesenchymal Stem Cells.

Pulsed electromagnetic field therapy, or pulsed signal therapy, has shown efficacy in treating many illnesses, including knee osteoarthritis. Although the mechanism is not fully understood, magnetic therapy is broadly welcomed because of its safe and noninvasive nature. At the cellular and molecular level, remote control of the cell fate by the magnetic field also has profound applications in both basic science and translational research. Here we demonstrate the use of pulsed electromagnetic field, one of the most benign and noninvasive extracellular cues, as a novel method to control specific chondrogenic differentiation of mesenchymal stem cells (MSCs). Chondrogenesis of transplanted MSCs inside the joint is considered one of the future therapies to rebuild the damaged cartilage. Here we show that pulsed electromagnetic field promotes chondrogenic differentiation of MSCs, and such a promoting effect can be drastically enhanced by the combined use of a magnetic hydrogel as the cell growth matrix. The magnetic hydrogel, synthesized by chemical cross-linking of gelatin and ß-cyclodextrin and by embedding Fe3O4 magnetic nanoparticles in the hydrogel network, supports adhesion, growth, and proliferation of MSCs. Pulsed electromagnetic field boosts chondrogenesis of MSCs grown on the magnetic hydrogel, manifested by enhanced toluidine blue staining; higher expression of collagen II protein; and upregulation of collagen II, aggrecan, and SOX9 genes. Therefore, our work presents a robust method for chondrogenesis of MSCs using magnetic field as the external cue.