PROTAC EZH2 degrader-1 overcomes the resistance of podophyllotoxin derivatives in refractory small cell lung cancer with leptomeningeal metastasis.

BACKGROUND: Leptomeningeal metastasis (LM) of small cell lung cancer (SCLC) is a highly detrimental occurrence associated with severe neurological disorders, lacking effective treatment currently. Proteolysis-targeting chimeric molecules (PROTACs) may provide new therapeutic avenues for treatment of podophyllotoxin derivatives-resistant SCLC with LM, warranting further exploration. METHODS: The SCLC cell line H128 expressing luciferase were mutated by MNNG to generate H128-Mut cell line. After subcutaneous inoculation of H128-Mut into nude mice, H128-LM and H128-BPM (brain parenchymal metastasis) cell lines were primarily cultured from LM and BPM tissues individually, and employed to in vitro drug testing. The SCLC-LM mouse model was established by inoculating H128-LM into nude mice via carotid artery and subjected to in vivo drug testing. RNA-seq and immunoblotting were conducted to uncover the molecular targets for LM. RESULTS: The SCLC-LM mouse model was successfully established, confirmed by in vivo live imaging and histological examination. The upregulated genes included EZH2, SLC44A4, VEGFA, etc. in both BPM and LM cells, while SLC44A4 was particularly upregulated in LM cells. When combined with PROTAC EZH2 degrader-1, the drug sensitivity of cisplatin, etoposide (VP16), and teniposide (VM26) for H128-LM was significantly increased in vitro. The in vivo drug trials with SCLC-LM mouse model demonstrated that PROTAC EZH2 degrader-1 plus VM26 or cisplatin/ VP16 inhibited H128-LM tumour significantly compared to VM26 or cisplatin/ VP16 alone (P < 0.01). CONCLUSION: The SCLC-LM model effectively simulates the pathophysiological process of SCLC metastasis to the leptomeninges. PROTAC EZH2 degrader-1 overcomes chemoresistance in SCLC, suggesting its potential therapeutic value for SCLC LM.

Systematic profiling of Taxol resistance and sensitivity to tubulin missence mutations at molecular and cellular levels.

Taxol (paclitaxel) is the first approved microtubule-stabilizing agent (MSA) by binding stoichiometrically to tubulin, which is considered to be one of the most significant advances in first-line chemotherapy against diverse tumors. However, a large number of residue missence mutations harboring in the tubulin have been observed to cause acquired drug resistance, largely limiting the clinical application of Taxol and its analogs in chemotherapy. A systematic investigation of the intermolecular interactions between the Taxol and various tubulin mutants would help to establish a comprehensive picture of drug response to tubulin mutations in clinical treatment of cancer, and to design new MSA agents with high potency and selectivity to overcome drug resistance. In this study, we described an integration of in silico analysis and in vitro assay (iSiV) to profile Taxol against a panel of 149 clinically observed, cancer-associated missence mutations in ß-tubulin at molecular and cellular levels, aiming to a systematic understanding of molecular mechanism and biological implication underlying drug resistance and sensitivity conferring from tubulin mutations. It is revealed that the Taxol-resistant mutations can be classified into three types: (I) nonbonded interaction broken due to mutation, (II) steric hindrance caused by mutation, and (III) conformational change upon mutation. In addition, we identified three new Taxol-resistant mutations (C239Y, T274I, and R320P) that can largely reduce the binding affinity of Taxol to tubulin at molecular level, in which the T274I and R320P were observed to considerably impair the antitumor activity of Taxol at cellular level. Moreover, a novel drug-susceptible mutation (M363T) was also identified, which improves Taxol affinity by 2.6-fold and decreases Taxol antitumor EC50 values from 29.4 to 18.7 µM.

Relationship Between Urinary Iodine Concentration and the Prevalence of Thyroid Nodules and Subclinical Hypothyroidism.

The aim of the study was to investigate the iodine intake in the resident population in Xi'an and analyze the relationship between iodine nutritional status and the prevalence of subclinical hypothyroidism and thyroid nodules (TNs). A total of 2507 people were enrolled in Xi'an. Venous serum thyroid stimulating hormone (TSH), thyroid peroxidase antibody (TPOAb) and thyroglobulin antibody (TgAb), urinary iodine concentration (UIC), and thyroid ultrasonography were collected. Patients with abnormal TSH were checked for free thyroxine (FT4) and triiodothyronine (FT3). Adults in Xi'an had median UICs of 220.80 µg/L and 178.56 µg/l, respectively. A sum of 16.78% of people had subclinical hypothyroidism. Both iodine excess and iodine deficit increased the frequency of subclinical hypothyroidism. The lowest was around 15.09% in females with urine iodine levels between 200 and 299 µg/l. With a rate of 10.69%, the lowest prevalence range for males was 100-199 µg/l. In Xi'an, 11.37% of people have TNs. In comparison to other UIC categories, TN occurrences were higher in females (18.5%) and males (12%) when UIC were below 100 µg/l. In conclusion, iodine intake was sufficient in the Xi'an area, while the adults' UIC remains slightly higher than the criteria. Iodine excess or deficiency can lead to an increase in the prevalence of subclinical hypothyroidism. Patients with iodine deficiency are more likely to develop TNs.

KIF2A Upregulates PI3K/AKT Signaling through Polo-like Kinase 1 (PLK1) to Affect the Proliferation and Apoptosis Levels of Eriocheir sinensis Spermatogenic Cells.

E. sinensis is an animal model for studying the reproduction and development of crustaceans. In this study, we knocked down the Es-Kif2a gene by injecting dsRNA into E. sinensis and inhibited Es-Plk1 gene expression by injecting PLK1 inhibitor BI6727 into E. sinensis. Then, the cell proliferation level, apoptosis level, and PI3K/AKT signaling expression level were detected. Our results showed that the proliferation level of spermatogenic cells decreased, while the apoptosis level increased after Es-Kif2a knockdown or Es-Plk1 inhibition. In order to verify whether these changes are caused by regulating the PI3K/AKT pathway, we detected the expression of PI3K and AKT proteins after Es-Kif2a knockdown or Es-Plk1 inhibition. Western Blot showed that in both the Es-Kif2a knockdown group and the Es-Plk1 inhibition group, the expression of PI3K and AKT proteins decreased. In addition, immunofluorescence showed that Es-KIF2A and Es-PLK1 proteins were co-localized during E. sinensis spermatogenesis. To further explore the upstream and downstream relationship between Es-KIF2A and Es-PLK1, we detected the expression level of Es-PLK1 after Es-Kif2a knockdown as well as the expression level of Es-KIF2A after Es-Plk1 inhibition. Western Blot showed that the expression of Es-PLK1 decreased after Es-Kif2a knockdown, while there was no significant change of Es-KIF2A after Es-Plk1 inhibition, indicating that Es-PLK1 may be a downstream factor of Es-KIF2A. Taken together, these results suggest that Es-KIF2A upregulates the PI3K/AKT signaling pathway through Es-PLK1 during the spermatogenesis of E. sinensis, thereby affecting the proliferation and apoptosis levels of spermatogenic cells.

Effect of bone mass density and alveolar bone resorption on stress in implant restoration of free-end edentulous posterior mandible: Finite element analysis of double-factor sensitivity.

BACKGROUND: Osseous condition of the mandible was regarded as a key factor influencing stability of implants in the early stage. Finite element analysis was used to assess the effect of bone mass density and alveolar bone resorption (double factors) on stress in a four-unit implant restoration of a free-end edentulous posterior mandible. METHODS: A 3D finite element model was constructed for a single-sided free-end edentulous mandible (from mandibular first premolar to mandibular second molar) containing threaded dental implants. Mandible sensitivity modes were constructed with different alveolar bone resorption levels for normal conditions as well as mild, moderate and severe periodontitis, respectively. Based on the mass density of cancellous bone for four types of bones as the sensitivity parameter, two implant design modes were constructed: Model A (four-unit fixed bridge supported by three implants, implant positions were 34, 36 and 37) and model B: 34 × 36, 37 (37: a single implant crown) (34 × 36: three-unit fixed bridge supported by two implants, implant positions were 34 and 36). A total of 32 sensitivity-based finite element models, grouped in two groups, were constructed. Stress distribution and maximum von Mises stress on cortical bone and cancellous bone around the implant, as well as the surface of implant were investigated by using ABAQUS when vertical loading and 45° oblique loading were applied, respectively. RESULTS: When vertical loading was applied on the implant, maximum von Mises stress on the cortical bone around the implant was assessed to be 4.726 MPa - 13.15 MPa and 6.254 MPa - 13.79 MPa for groups A and B, respectively; maximum stress on the cancellous bone around the implant was 2.641 MPa - 3.773 MPa and 2.864 MPa - 4.605 MPa, respectively; maximum stress on the surface of implant was 14.7 MPa - 21.17 MPa and 21.64 MPa - 30.70 MPa, respectively. When 45° oblique loading was applied on the implant restoration, maximum von Mises stress on the cortical bone around the implant was assessed to be 42.08 MPa - 92.71 MPa and 50.84 MPa - 102.5 MPa for groups A and B, respectively; maximum stress on the cancellous bone around the implant was 4.88 MPa - 25.95 MPa and 5.227 MPa - 28.43 MPa, respectively; maximum stress on the surface of implant was 77.91 MPa - 124.8 MPa and 109.2 MPa - 150.7 MPa, respectively. Stress peak on the cortical bone and that on cancellous bone around the implant increased and decreased with the decrease in bone mass density, respectively. Stress peak on alveolar bone increased with alveolar bone resorption when oblique loading was applied. CONCLUSION: 1. Both alveolar bone resorption and bone mass density (double factors) are critical to implant restoration. Bone mass density may exhibit a more pronounced impact than alveolar bone resorption. 2. From the biomechanical perspective, types I and II bones are preferred for implant restoration, while implantation should be considered carefully in the case of type III bones, or those with less bone mass density accompanied by moderate to severe alveolar bone loss. 3. Splinting crowns restoration is biomechanically superior to single crown restoration.

Transformation to small cell lung cancer is irrespective of EGFR and accelerated by SMAD4-mediated ASCL1 transcription independently of RB1 in non-small cell lung cancer.

OBJECTIVES: Histological transformation to small cell lung cancer (SCLC) has been identified as a mechanism of TKIs resistance in EGFR-mutant non-small cell lung cancer (NSCLC). We aim to explore the prevalence of transformation in EGFR-wildtype NSCLC and the mechanism of SCLC transformation, which are rarely understood. METHODS: We reviewed 1474 NSCLC patients to investigate the NSCLC-to-SCLC transformed cases and the basic clinical characteristics, driver gene status and disease course of them. To explore the potential functional genes in SCLC transformation, we obtained pre- and post-transformation specimens and subjected them to a multigene NGS panel involving 416 cancer-related genes. To validate the putative gene function, we established knocked-out models by CRISPR-Cas 9 in HCC827 and A549-TP53-/- cells and investigated the effects on tumor growth, drug sensitivity and neuroendocrine phenotype in vitro and in vivo. We also detected the expression level of protein and mRNA to explore the molecular mechanism involved. RESULTS: We firstly reported an incidence rate of 9.73% (11/113) of SCLC transformation in EGFR-wildtype NSCLC and demonstrated that SCLC transformation is irrespective of EGFR mutation status (P = 0.16). We sequenced 8 paired tumors and identified a series of mutant genes specially in transformed SCLC such as SMAD4, RICTOR and RET. We firstly demonstrated that SMAD4 deficiency can accelerate SCLC transition by inducing neuroendocrine phenotype regardless of RB1 status in TP53-deficient NSCLC cells. Further mechanical experiments identified the SMAD4 can regulate ASCL1 transcription competitively with Myc in NSCLC cells and Myc inhibitor acts as a potential subsequent treatment agent. CONCLUSIONS: Transformation to SCLC is irrespective of EFGR status and can be accelerated by SMAD4 in non-small cell lung cancer. Myc inhibitor acts as a potential therapeutic drug for SMAD4-mediated resistant lung cancer. Video Abstract.

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.

The effect of root canal treatment and post-crown restorations on stress distribution in teeth with periapical periodontitis: a finite element analysis.

AIM: To evaluate the effects of root canal treatment (RCT) and post-crown restoration on stress distribution in teeth with periapical bone defects using finite element analysis. METHODOLOGY: Finite element models of mandibular second premolars and those with periapical bone defects (spherical defects with diameters of 5, 10, 15, and 20 mm) were created using digital model design software. The corresponding RCT and post-crown restoration models were constructed based on the different sizes of periapical bone defect models. The von Mises stress and tooth displacement distributions were comprehensively analyzed in each model. RESULTS: Overall analysis of the models: RCT significantly increased the maximum von Mises stresses in teeth with periapical bone defects, while post-crown restoration greatly reduced the maximum von Mises stresses. RCT and post-crown restoration slightly reduced tooth displacement in the affected tooth. Internal analysis of tooth: RCT dramatically increased the maximum von Mises stress in all regions of the tooth, with the most pronounced increase in the coronal surface region. The post-crown restoration balances the internal stresses of the tooth and is most effective in periapical bone defect - 20-mm model. RCT and post-crown restoration slightly reduced the tooth displacement in all regions of the affected tooth. CONCLUSIONS: Root canal treatment seemed not to improve the biomechanical state of teeth with periapical bone defects. In contrast, post-crown restoration might effectively balance the stress concentrations caused by periapical bone defects, particularly extensive ones.

The effect of periapical bone defects on stress distribution in teeth with periapical periodontitis: a finite element analysis.

BACKGROUND: Apical periodontitis directly affects the stress state of the affected tooth owing to the destruction of the periapical bone. Understanding the mechanical of periapical bone defects/tooth is clinically meaningful. In this study, we evaluate the effect of periapical bone defects on the stress distribution in teeth with periapical periodontitis using finite element analysis. METHODS: Finite element models of normal mandibular second premolars and those with periapical bone defects (spherical defects with diameters of 5, 10, 15, and 20 mm) were created using a digital model design software. The edges of the mandible were fixed and the masticatory cycle was simplified as oblique loading (a 400 N force loaded obliquely at 45° to the long axis of the tooth body) to simulate the tooth stress state in occlusion and analyze the von Mises stress distribution and tooth displacement distribution in each model. RESULTS: Overall analysis of the models: Compared to that in the normal model, the maximum von Mises stresses in all the different periapical bone defect size models were slightly lower. In contrast, the maximum tooth displacement in the periapical bone defect model increased as the size of the periapical bone defect increased (2.11-120.1% of increase). Internal analysis of tooth: As the size of the periapical bone defect increased, the maximum von Mises stress in the coronal cervix of the tooth gradually increased (2.23-37.22% of increase). while the von Mises stress in the root apical region of the tooth showed a decreasing trend (41.48-99.70% of decrease). The maximum tooth displacement in all parts of the tooth showed an increasing trend as the size of the periapical bone defect increased. CONCLUSIONS: The presence of periapical bone defects was found to significantly affect the biomechanical response of the tooth, the effects of which became more pronounced as the size of the bone defect increased.

Combining the Tyrosine Kinase Inhibitor Cabozantinib and the mTORC1/2 Inhibitor Sapanisertib Blocks ERK Pathway Activity and Suppresses Tumor Growth in Renal Cell Carcinoma.

Current treatment approaches for renal cell carcinoma (RCC) face challenges in achieving durable tumor responses due to tumor heterogeneity and drug resistance. Combination therapies that leverage tumor molecular profiles could offer an avenue for enhancing treatment efficacy and addressing the limitations of current therapies. To identify effective strategies for treating RCC, we selected ten drugs guided by tumor biology to test in six RCC patient-derived xenograft (PDX) models. The multitargeted tyrosine kinase inhibitor (TKI) cabozantinib and mTORC1/2 inhibitor sapanisertib emerged as the most effective drugs, particularly when combined. The combination demonstrated favorable tolerability and inhibited tumor growth or induced tumor regression in all models, including two from patients who experienced treatment failure with FDA-approved TKI and immunotherapy combinations. In cabozantinib-treated samples, imaging analysis revealed a significant reduction in vascular density, and single-nucleus RNA sequencing (snRNA-seq) analysis indicated a decreased proportion of endothelial cells in the tumors. SnRNA-seq data further identified a tumor subpopulation enriched with cell-cycle activity that exhibited heightened sensitivity to the cabozantinib and sapanisertib combination. Conversely, activation of the epithelial-mesenchymal transition pathway, detected at the protein level, was associated with drug resistance in residual tumors following combination treatment. The combination effectively restrained ERK phosphorylation and reduced expression of ERK downstream transcription factors and their target genes implicated in cell-cycle control and apoptosis. This study highlights the potential of the cabozantinib plus sapanisertib combination as a promising treatment approach for patients with RCC, particularly those whose tumors progressed on immune checkpoint inhibitors and other TKIs. SIGNIFICANCE: The molecular-guided therapeutic strategy of combining cabozantinib and sapanisertib restrains ERK activity to effectively suppress growth of renal cell carcinomas, including those unresponsive to immune checkpoint inhibitors.

Assessment tools for stigma in breast cancer patients based on COSMIN guidelines: a systematic review.

OBJECTIVE: The objective of this study was to conduct a systematic review of the measurement properties and methodological quality of stigma assessment tools designed for breast cancer patients. The aim was to provide clinical medical staff with a foundation for selecting high-quality assessment tools. METHODS: A comprehensive computer search was carried out across various databases, including SinoMed, China National Knowledge Infrastructure (CNKI), Wanfang Database, China Science and Technology Journal Database(VIP), Embase, PubMed, Web of Science, The Cochrane Library, and Scopus, which were searched from the inception of the databases until March 20, 2023. Literature screening and data extraction were performed independently by two researchers, adhering to predefined inclusion and exclusion criteria. The assessment tools were evaluated using the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) systematic evaluation guidelines. RESULTS: In the final analysis, a total of 9 assessment tools were included. However, none of these tools addressed measurement error, cross-cultural validity, criterion validity, and responsiveness. Following the COSMIN guidelines, BCSS and CSPDS were assigned to Class A recommendations, while the remaining tools received Class B recommendations. CONCLUSION: The BCSS and CSPDS scales demonstrated comprehensive assessment in terms of their measurement characteristics, exhibiting good methodological quality, measurement attribute quality, and supporting evidence. Therefore, it is recommended to utilize these scales for evaluating breast cancer stigma. However, further validation is required for the remaining assessment tools.

Efficacy of sequential chemoradiotherapy combined with toripalimab in de novo metastatic nasopharyngeal carcinoma: A phase II trial.

Locoregional radiotherapy added to chemotherapy has significantly improved survival in de novo metastatic nasopharyngeal carcinoma (mNPC). However, only 54% of de novo mNPC patients who received sequential chemoradiotherapy have complete or partial response 3 months after radiotherapy. This Simon's optimal two-stage design phase II study (NCT04398056) investigates whether PD-1 inhibitor could improve tumor control in combination with chemoradiation. The primary endpoint is objective response rate (ORR) at 3 months after radiotherapy. Twenty-two patients with primary mNPC are enrolled. The ORR at 3 months after radiotherapy is 81.8% (22.7% complete response, n = 5; 59.1% partial response, n = 13), and the disease control rate is 81.8%. The 3-year progression-free survival (PFS) rate is 44.9% (95% confidence interval 26.4%-76.3%). Fifteen patients (68.2%) experienced grade 3-4 adverse events. Patients with high baseline plasma Epstein-Barr virus DNA copy number (>104 cps/mL) show worse PFS. Addition of toripalimab to sequential chemoradiotherapy suggests promising tumor response in patients with primary mNPC.

Reliability and validity of the Chinese version of the trauma-specific frailty index (TSFI) for geriatric trauma patients.

BACKGROUND: Pre-traumatic frailty in geriatric trauma patients has caught attention from emergency medical workers and the assessment of it thus become one of the important aspects of risk management. Several tools are available to identify frailty, but limited tools have been validated for geriatric trauma patients in China to assess pre-traumatic frailty.The aim of this study is to translate the Trauma-Specific Frailty Index(TSFI) into Chinese, and to evaluate the reliability and validity of the translated version in geriatric trauma patients. METHODS: A cross-sectional study was conducted. The TSFI was translated with using the Brislin model, that included forward and backward translation. A total of 184 geriatric trauma patients were recruited by a convenience sampling between October and December 2020 in Hospital of Chengdu University of Traditional Chinese Medicine, Sichuan. Using reliability or internal consistency tests assessed with Cronbach's alpha coefficient, split-half reliability and test-retest reliability. Content validity and construct validity analysis were both performed. Sensitivity, specificity and maximum Youden index(YI) were used to determine the optimal cut-off value. The screening performance was examined by Kappa value. RESULTS: The total study population included 184 subjects, of which 8 participants were excluded, resulting in a study sample size of 176 elderly trauma patients (the completion rate was 95.7%). The Chinese version of Trauma-Specific Frailty Index(C-TSFI) have 15 items with 5 dimensions. Cronbach's alpha coefficient of the C-TSFI was 0.861, Cronbach's alpha coefficient of dimensions ranged from 0.837 to 0.875, the split-half reliability of the C-TSFI were 0.894 and 0.880 respectively, test-retest reliability ranged from 0.692 to 0.862. The correlation coefficient between items and the C-TSFI ranged from 0.439 to 0.761. The content validity index for items (I-CVI) of the C-TSFI scale was 0.86~1.00, and the scale of content validity index (S-CVI) was 0.93. The area under curve (AUC) of the C-TSFI was 0.932 (95%CI 0.904-0.96, P < 0.05), the maximum YI was 0.725, the sensitivity was 80.2%, the specificity was 92.3%, and the critical value was 0.31. Kappa value was 0.682 (P < 0.05). CONCLUSIONS: The Chinese version of TSFI could be used as a general assessment tool in geriatric trauma patients, and both its reliability and validity have been demonstrated.

Responses of photosynthetic characteristics of Phragmites australis to simulated warming in salt marshes of the Yellow Sea and Bohai Sea, China.

Coastal wetlands are highly efficient in blue carbon sequestration. The impacts of climate warming on photosynthetic rates and light response characteristics of wetland plants would change the magnitude of carbon sequestration in coastal wetlands. We constructed warming observation stations in Phragmites australis (Phragmites) wetlands located in the Yellow River Delta in Dongying with dry climate, and in Yancheng by the Yellow Sea with wet climate. By using a Li-6800 photosynthesis system, we investigated the responses of simulated warming on photosynthetic characteristics of Phragmites in both wetlands, and compared the difference between months (June and August) in Dongying wetland. The results showed the photosynthetic rates of Phragmites were higher in June than in August. Warming increased net photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (gs) and intercellular carbon dioxide concentration (Ci) in the two months, but the variability of Pn to warming was lower in August. The Pn and water use efficiency (WUE) of Phragmites in the Yancheng wetland were higher than Dongying wetland, and the maximum net photosynthetic rate (Pn max), light saturation point (LSP), apparent quantum efficiency (AQY), and dark respiration rate (Rd) of the former responded more positively to warming. The values of AQY, LSP and Pn max of Phragmites in the Yancheng wetlands were increased by 16.7%, 53.6% and 30.3%, respectively, in the warming plots. Our results suggested that warming could improve the utilization efficiency of weak light, the adaptability to strong light and photosynthetic potential of Phragmites under rainy and humid conditions. This study is of importance for accurately quantifying carbon sequestration of coastal wetlands at the regional and seasonal scales in the context of climate warming.

Tidal effects on carbon dioxide emission dynamics in intertidal wetland sediments.

Understanding the control mechanisms of carbon dioxide (CO2) emissions in intertidal wetland sediments is beneficial for the concern of global carbon biogeochemistry and climate change. Nevertheless, multiple controls on CO2 emissions from intertidal wetland sediments to the atmosphere still need to be clarified. This study investigated the effect of tidal action on CO2 emissions from salt marsh sediments covered by Spartina alterniflora in the Jiaozhou Bay wetland using the static chamber method combined with an infrared CO2 detector. The results showed that the CO2 emission fluxes from the sediment during ebb tides were higher than those during flood tides. The whole wetland sediment acted as a weak source of atmospheric CO2 (average flux: 24.44 ± 16.80 mg C m-2 h-1) compared to terrestrial soils and was affected by the cycle of seawater inundation and exposure. The tidal influence on vertical dissolved inorganic carbon (DIC) transport in the sediment was also quantitated using a two-end member mixing model. The surface sediment layer (5-15 cm) with maximum DIC concentration during ebb tides became the one with minimum DIC concentration during flood tides, indicating the DIC transport from the surface sediment to seawater. Furthermore, aerobic respiration by microorganisms was the primary process of CO2 production in the sediment according to 16 S rDNA sequencing analysis. This study revealed the strong impact of tidal action on CO2 emissions from the wetland sediment and provided insights into the source-sink pattern of CO2 and DIC at the land-ocean interface.

Excessive Thyroid Hormone Signaling Induces Photoreceptor Degeneration in Mice.

Rod and cone photoreceptors degenerate in inherited and age-related retinal degenerative diseases, ultimately leading to loss of vision. Thyroid hormone (TH) signaling regulates cell proliferation, differentiation, and metabolism. Recent studies have shown a link between TH signaling and retinal degeneration. This work investigates the effects of excessive TH signaling on photoreceptor function and survival in mice. C57BL/6, Thra1 -/-, Thrb2 -/-, Thrb -/-, and the cone dominant Nrl -/- mice received triiodothyronine (T3) treatment (5-20 µg/ml in drinking water) for 30 d, followed by evaluations of retinal function, photoreceptor survival/death, and retinal stress/damage. Treatment with T3 reduced light responses of rods and cones by 50-60%, compared with untreated controls. Outer nuclear layer thickness and cone density were reduced by ∼18% and 75%, respectively, after T3 treatment. Retinal sections prepared from T3-treated mice showed significantly increased numbers of TUNEL-positive, p-γH2AX-positive, and 8-OHdG-positive cells, and activation of Müller glial cells. Gene expression analysis revealed upregulation of the genes involved in oxidative stress, necroptosis, and inflammation after T3 treatment. Deletion of Thra1 prevented T3-induced degeneration of rods but not cones, whereas deletion of Thrb2 preserved both rods and cones. Treatment with an antioxidant partially preserved photoreceptors and reduced retinal stress responses. This study demonstrates that excessive TH signaling induces oxidative stress/damage and necroptosis, induces photoreceptor degeneration, and impairs retinal function. The findings provide insights into the role of TH signaling in retinal degeneration and support the view of targeting TH signaling for photoreceptor protection.

Comparative mechanistic study of RPE cell death induced by different oxidative stresses.

Oxidative stress is hypothesized to drive the progression of age-related macular degeneration (AMD). Retinal pigment epithelial (RPE) cell layer is important for supporting the function of retina and is particularly susceptible to oxidative stress-induced cell death. How RPE cells die in AMD, especially in geographic atrophy (GA), a late stage of dry AMD, is still controversial. The goal of this study is to compare the features and mechanisms of RPE cell death induced by different oxidative stresses, to identify potential universal therapeutic targets for GA. RPE cell death was induced both in vitro and ex vivo by 4-Hydroxynonenal (4-HNE), a major product of lipid peroxidation, sodium iodate (NaIO3) that has been widely used to model RPE cell death in dry AMD, a ferroptosis inducer RAS-selective lethal 3 (RSL3) or a necroptosis inducer shikonin. We found that RPE necroptosis and ferroptosis show common and distinct features. Common features include receptor-interacting protein kinase (RIPK)1/RIPK3 activation and lipid reactive oxygen species (ROS) accumulation, although lipid ROS accumulation is much milder during necroptosis. This supports cross talk between RPE ferroptosis and necroptosis pathways and is consistent with the rescue of RPE necroptosis and ferroptosis by RIPK1 inhibitor Necrostatin-1 (Nec-1) or in Ripk3-/- RPE explants. Distinct feature includes activated mixed lineage kinase domain like pseudokinase (MLKL) that is translocated to the cell membrane during necroptosis, which is not happening in ferroptosis. This is consistent with the failure to rescue RPE ferroptosis by MLKL inhibitor necrosulfonamide (NSA) or in Mlkl-/- RPE explants. Using this framework, we found that 4-HNE and NaIO3 induced RPE cell death likely through necroptosis based on the molecular features and the rescuing effect by multiple inhibitors. Our studies suggest that multiple markers and inhibitors are required to distinguish RPE necroptosis and ferroptosis, and that necroptosis inhibitor Nec-1 could be a potential therapeutic compound for GA since it inhibits RIPK1/RIPK3 activation and lipid ROS accumulation occurred in both necroptosis and ferroptosis pathways.

Inhibition of Ryanodine Receptor 1 Reduces Endoplasmic Reticulum (ER) Stress and Promotes ER Protein Degradation in Cyclic Nucleotide-Gated Channel Deficiency.

The cone photoreceptor cyclic nucleotide-gated (CNG) channel plays a pivotal role in cone phototransduction. Mutations in genes encoding the channel subunits CNGA3 and CNGB3 account for about 80% of all cases of achromatopsia and are associated with progressive cone dystrophies. CNG channel deficiency leads to cellular/endoplasmic reticulum (ER) calcium dysregulation and ER stress-associated cone apoptosis. This work investigated the role of the ER calcium channel ryanodine receptor 1 (Ryr1) in ER stress and cone degeneration in CNG channel deficiency. The AAV-mediated CRISPR/SaCas9 genome editing was used to knock down Ryr1 specifically in cones. CNG channel-deficient mice displayed improved cone survival after subretinal injection of AAV2-SaCas9/gRNA-Ryr1, manifested as increased expression levels of cone proteins M-opsin, S-opsin, and cone arrestin. Knockdown of Ryr1 also led to reduced ER stress and increased expression levels of the ER-associated degradation proteins. This work demonstrates a role of Ryr1 in ER stress and cone degeneration in CNG channel deficiency, and supports strategies targeting ER calcium regulation for cone preservation.

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.

Subtractionless compressed-sensing-accelerated whole-body MR angiography using two-point Dixon fat suppression with single-pass half-reduced contrast dose: feasibility study and initial experience.

PURPOSE: To investigate the feasibility and clinical utility of a compressed-sensing-accelerated subtractionless whole-body MRA (CS-WBMRA) protocol with only contrast injection for suspected arterial diseases, by comparison to conventional dual-pass subtraction-based whole-body MRA (conventional-WBMRA) and available computed tomography angiography (CTA). MATERIALS AND METHODS: This prospective study assessed 86 patients (mean age, 56 years ± 16.4 [standard deviation]; 25 women) with suspected arterial diseases from May 2021 to December 2022, who underwent CS-WBMRA (n = 48, mean age, 55.9 years ± 16.4 [standard deviation]; 25 women) and conventional-WBMRA (n = 38, mean age, 48 years ± 17.4 [standard deviation]; 20 women) on a 3.0 T MRI after random group assignment based on the chronological order of enrolment. Of all enrolled patients administered the CS-WBMRA protocol, 35% (17/48) underwent CTA as required by clinical demands. Two experienced radiologists independently scored the qualitative image quality and venous enhancement contamination. Quantitative image assessment was carried out by determining and comparing the apparent signal-to-noise ratios (SNRs) and contrast-to-noise ratios (CNRs) of four representative arterial segments. The total examination time and contrast-dose were also recorded. The independent samples t-test or the Wilcoxon rank sum test was used for statistical analysis. RESULTS: The overall scores of CS-WBMRA outperformed those of conventional-WMBRA (3.40 ± 0.60 vs 3.22 ± 0.55, P < 0.001). In total, 1776 and 1406 arterial segments in the CS-WBMRA and conventional-WBMRA group were evaluated. Qualitative image scores for 7 (of 15) vessel segments in the CS-WMBRA group had statistically significantly increased values compared to those of the conventional-WBMRA groups (P < 0.05). Scores from the other 8 segments showed similar image quality (P > 0.05) between the two protocols. In the quantitative analysis, overall apparent SNRs were significantly higher in the conventional-WBMRA group than in the CS-WBMRA group (214.98 ± 136.05 vs 164.90 ± 118.05; P < 0.001), while overall apparent CNRs were not significantly different in these two groups (CS vs conventional: 107.13 ± 72.323 vs 161.24 ± 118.64; P > 0.05). In the CS-WBMRA group, 7 of 1776 (0.4%) vessel segments were contaminated severely by venous enhancement, while in the convention-WBMRA group, 317 of 1406 (23%) were rated as severe contamination. In the CS-WBMRA group, total examination and reconstruction times were only 7 min and 10 min, respectively, vs 20 min and < 30 s for the conventional WBMRA group, respectively. The contrast agent dose used in the CS-WBMRA protocol was reduced by half compared to conventional-WBMRA protocol (18.7 ± 3.5 ml vs 37.2 ± 5.4 ml, P = 0.008). CONCLUSION: The CS-WBMRA protocol provides excellent image quality and sufficient diagnostic accuracy for whole-body arterial disease, with relatively faster workflow and half-dose reduction of contrast agent, which has greater potential in clinical practice compared with conventional-WBMRA.