CircFLNA facilitates gastric cancer cell proliferation and glycolysis via regulating SOX5 by sponging miR-1200.

BACKGROUND AND STUDY AIMS: Circular RNAs (circRNAs) are important regulators for gastric cancer (GC) progression. Our study aims to investigate the role and mechanism of circFLNA in GC progression. PATIENTS AND METHODS: The levels of circFLNA, microRNA (miR)-1200 and SRY-box transcription factor 5 (SOX5) were examined using qRT-PCR. Flow cytometry, cell counting kit 8 assay and EdU assay were performed to measure cell proliferation and apoptosis. Cell glycolysis ability was assessed by examining glucose uptake and lactate produce. RNA interaction was determined using RNA pull-down assay and dual-luciferase reporter assay. Mice xenograft models were constructed to evaluate the regulation of circFLNA knockdown on GC tumor growth. RESULTS: CircFLNA was upregulated in GC tissues. Functional experiments showed that circFLNA knockdown suppressed GC cell proliferation, inhibited glycolysis, and promoted apoptosis in vitro, as well as reduced GC tumor growth in vivo. CircFLNA sponged miR-1200, and miR-1200 targeted SOX5. MiR-1200 mimic reversed the promotion effect of circFLNA overexpression on GC cell growth and glycolysis, and SOX5 upregulation also abolished the inhibiting effect of miR-1200 mimic on GC cell growth and glycolysis. CONCLUSION: Our data suggest that circFLNA might exert oncogenic role in GC development, which promoted GC proliferation and glycolysis through regulating miR-1200/SOX5 axis.

Efficacy of neoadjuvant chemotherapy combined with prophylactic intraperitoneal hyperthermic chemotherapy for patients diagnosed with clinical T4 gastric cancer who underwent laparoscopic radical gastrectomy: a retrospective cohort study based on propensity score matching.

BACKGROUND: Clinical T4 (cT4) stage gastric cancer presents with frequent postoperative recurrence and poor prognosis. This study is to evaluate the oncological efficacy of laparoscopic radical total gastrectomy combined with postoperative prophylactic hyperthermic intraperitoneal chemotherapy (HIPEC) in patients with cT4N + M0 gastric cancer who received neoadjuvant chemotherapy. METHODS: We reviewed the clinicopathological data of 174 patients with clinical T4 gastric cancer who underwent neoadjuvant chemotherapy followed by laparoscopic radical total gastrectomy between June 2017 and December 2021. Among them, 142 were included in the non-HIPEC group, and 32 in the HIPEC group. Patients in both groups were paired based on propensity score in a 2:1 ratio to assess disparities in tumor recurrence and long-term survival. RESULTS: After matching, there were no significant differences in the clinicopathological data between the two groups. The peritoneum (16.1%) and distant organs (10.9%) were the most frequent locations for recurrence. Prior to matching, the recurrence rates were similar at all sites for both groups. Compared with those in the non-HIPEC cohort, the recurrence rates at all sites, the lung, and the peritoneum were notably lower in the HIPEC cohort. Prior to matching, the 3-year overall survival and disease-free survival rates were similar between the two groups; following matching, the HIPEC group exhibited notably greater survival rates than did the non-HIPEC group. The disparities in survival rates between the groups became even more pronounced after conducting a stratified analysis among patients with stage III disease. CONCLUSIONS: Neoadjuvant chemotherapy combined with prophylactic HIPEC after laparoscopic radical gastrectomy can effectively reduce the rate of peritoneal metastasis in patients with cT4N + M0 advanced gastric cancer and significantly improve the prognosis of such patients, which is of great clinical value.

CCL17 and CCL19 are markers of disease progression in alveolar echinococcosis.

OBJECTIVES: Alveolar echinococcosis (AE) represents one of the deadliest helminthic infections, characterized by an insidious onset and high lethality. METHODS: This study utilized the Gene Expression Omnibus (GEO) database, applied Weighted Correlation Network Analysis (WGCNA) and Differential Expression Analysis (DEA), and employed the Matthews Correlation Coefficient (MCC) to identify CCL17 and CCL19 as key genes in AE. Immunohistochemistry and immunofluorescence co-localization techniques were used to examine the expression of CCL17 and CCL19 in liver tissue lesions of AE patients. Additionally, a mouse model of multilocular echinococcus larvae infection was developed to study the temporal expression patterns of these genes, along with liver fibrosis and inflammatory responses. RESULTS: The in vitro model simulating echinococcal larva infection mirrored the hepatic microenvironment post-infection with multilocular echinococcal tapeworms. Quantitative RT-PCR analysis showed that liver fibrosis occurred in AE patients, with proximal activation and increased expression of CCL17 and CCL19 over time post-infection. Notably, expression peaked during the late stages of infection. Similarly, F4/80, a macrophage marker, exhibited corresponding trends in expression. Upon stimulation of normal hepatocytes by vesicular larvae in cellular experiments, there was a significant increase in CCL17 and CCL19 expression at 12 h post-infection, mirroring the upregulation observed with F4/80. CONCLUSION: CCL17 and CCL19 facilitate macrophage aggregation via the chemokine pathway and their increased expression correlates with the progression of infection, suggesting their potential as biomarkers for AE progression.

The safety, feasibility, and oncological outcomes of laparoscopic completion total gastrectomy for remnant gastric cancer: a prospective study with 3-year follow-up (FUGES-004 study).

BACKGROUND: The efficacy of laparoscopic completion total gastrectomy (LCTG) for remnant gastric cancer (RGC) remains controversial. METHODS: The primary outcome was postoperative morbidity within 30 days after surgery. Secondary outcomes included 3-year disease-free survival (DFS), 3-year overall survival (OS), and recurrence. Inverse probability treatment weighted (IPTW) was used to balance the baseline between LCTG and OCTG. RESULTS: Final analysis included 46 patients with RGC who underwent LCTG at the FJMUUH between June 2016 and June 2020. The historical control group comprised of 160 patients who underwent open completion total gastrectomy (OCTG) in the six tertiary teaching hospitals from CRGC-01 study. After IPTW, no significant difference was observed between the LCTG and OCTG groups in terms of incidence (LCTG vs. OCTG: 28.0 vs. 35.0%, P =0.379) or severity of complications within 30 days after surgery. Compared with OCTG, LCTG resulted in better short-term outcomes and faster postoperative recovery. However, the textbook outcome rate was comparable between the two groups (45.9 vs. 32.8%, P =0.107). Additionally, the 3-year DFS and 3-year OS of LCTG were comparable to those of OCTG (DFS: log-rank P =0.173; OS: log-rank P =0.319). No significant differences in recurrence type, mean recurrence time, or 3-year cumulative hazard of recurrence were observed between the two groups (all P >0.05). Subgroup analyses and concurrent comparisons demonstrated similar trends. CONCLUSIONS: This prospective study suggested that LCTG was noninferior to OCTG in both short-term and long-term outcomes. In experienced centers, LCTG may be considered as a viable treatment option for RGC.

The safety and efficacy of neoadjuvant immunochemotherapy following laparoscopic gastrectomy for gastric cancer: a multicentre real-world clinical study.

BACKGROUND: The safety and efficacy of neoadjuvant immunochemotherapy (nICT) for locally advanced gastric cancer (LAGC) remain controversial. METHODS: Patients with LAGC who received either nICT or neoadjuvant chemotherapy (nCT) at 3 tertiary referral teaching hospitals in China between January 2016 and October 2022 were analyzed. After propensity-score matching (PSM), comparing the radiological response, pathological response rate, perioperative outcomes, and early recurrence between the two groups. RESULTS: After PSM, 585 patients were included, with 195 and 390 patients comprising the nICT and nCT groups, respectively. The nICT group exhibited a higher objective response rate (79.5% vs. 59.0%; P <0.001), pathological complete response rate (14.36% vs. 6.41%; P =0.002) and major pathological response rate (39.49% vs. 26.15%; P =0.001) compared with the nCT group. The incidence of surgical complications (17.44% vs. 16.15%, P =0.694) and the proportion of perioperative textbook outcomes (80.0% vs. 81.0%; P =0.767) were similar in both groups. The nICT group had a significantly lower proportion of early recurrence than the nCT group (29.7% vs. 40.8%; P =0.047). Furthermore, the multivariable logistic analysis revealed that immunotherapy was an independent protective factor against early recurrence [odds ratio 0.62 (95% CI 0.41-0.92); P =0.018]. No significant difference was found in neoadjuvant therapy drug toxicity between the two groups (51.79% vs. 45.38%; P =0.143). CONCLUSIONS: Compared with nCT, nICT is safe and effective, which significantly enhanced objective and pathological response rates and reduced the risk for early recurrence among patients with LAGC. TRIAL REGISTRATION: Clinical Trials.gov.

Identification and exploration of a new M2 macrophage marker MTLN in alveolar echinococcosis.

The pathogen of alveolar echinococcosis (AE) is Echinococcus multilocularis (E. multilocularis), which has the characteristics of diffuse infiltration and growth and has a high mortality rate. At present, the role of macrophages in AE infection has attracted more and more attention, but the new biomarkers and polarization mechanisms of macrophages are rarely studied. In this study, CIBERSORT and WGCNA algorithms were used to establish a weighted gene co-expression network, and MTLN was identified as a biological marker of M2-type macrophages, which participated in energy metabolism of macrophages and mediated inflammatory response, but the role of MTLN in AE was not studied. In this study, liver tissue samples from AE patients were collected and immunofluorescence co-localization showed the relationship between MTLN and macrophage distribution. E. multilocularis infected mouse model was established to analyze the expression of MTLN, liver fibrosis, and inflammatory reaction after E. multilocularis infection. The cell experiment simulated the liver microenvironment of E. multilocularis infected human body and analyzed the expression of MTLN by QRT-PCR and western blot in vitro. The data showed that liver fibrosis occurred in AE patients, and MTLN was activated near the focus. After E. multilocularis infected mice, the expression of MTLN increased with time. In the cell experiment, after the antigen of E. multilocularis protoscolex stimulated normal liver cells, the expression of MTLN increased 48 h, at this time, M2 was up-regulated and M1 was down-regulated. Therefore, MTLN may be the key gene to regulate the polarization of M2 macrophages and cause fibrosis.

Discovery of CDK signature and CDK5 as potential biomarkers for predicting prognosis and immunotherapeutic response in gastric cancer peritoneal metastases.

Gastric cancer peritoneal metastases (GCPM) are a leading cause of death in gastric cancer patients. In this study, we focused on the expression of cyclin-dependent protein kinases (CDK), essential regulators of transcription, metabolism, and cell differentiation, in GCPM. Utilizing the GSE62254 cohort, we established a CDK signature (CDKS) model comprising ten CDK gene family members. Analysis of both the GSE62254 and TCGA cohorts revealed that patients with low CDKS had a worse prognosis compared to those with high CDKS. Furthermore, patients with high CDKS demonstrated positive responses from immunotherapy, as observed in the KIM cohort. We investigated the association between CDKS and the tumor microenvironment, including immune escape mechanisms. Immunohistochemistry analysis revealed a positive correlation between CDK5 and PD-L1 expression in gastric cancer. Furthermore, we found that CDK5 knockdown led to the inhibition of PD-L1 expression in gastric cancer cells. Our findings highlight the potential of CDKS as a prognostic biomarker and an indicator of immunotherapy response in gastric cancer patients. Moreover, our study suggests that targeting CDK5 could provide a new pathway for exploring immunotherapeutic research.

Gastric cancer peritoneal metastasis related signature predicts prognosis and sensitivity to immunotherapy in gastric cancer.

Gastric cancer peritoneal metastases (GCPM) is a leading cause of GC-related death. Early detection of GCPM is critical for improving the prognosis of advanced GC. Differentially expressed genes (DEGs) were identified in the GSE62254 database to distinguish between GCPM and non-GCPM. The gastric cancer peritoneal metastases signature (GCPMs) was developed using DEGs. We analysed the effectiveness of GCPMs as indicators for prognosis, chemotherapy, and immune therapy response in GC patients. Subsequently, we analysed the correlation between GCPMs and immune microenvironment as well as immune escape in GC patients. Random forest model and immunohistochemistry was utilized to identify the crucial genes that can aid in the diagnosis of GCPM. We identified five DEGs and utilized their expression to construct GCPMs. Patients with high GCPMs had a higher likelihood of a poor prognosis, while those with low GCPMs appeared to potentially benefit more from chemotherapy. GCPMs were a dependable marker for predicting the response to immunotherapy. Additionally, GCPMs was found to be significantly linked to stromal score and cancer-associated fibroblasts. SYNPO2 has been identified as the gene with the highest significance in the diagnosis of GCPM. Immunohistochemistry suggests that SYNPO2-positive expression in tumour cells, fibroblasts, inflammatory cell may be associated with promoting peritoneal metastasis in GC. GCPMs have shown to be a promising biomarker for predicting the prognosis and response of GC patients to chemotherapy and immunotherapy. The use of GCPMs for individual tumour evaluation may pave the way for personalized treatment for GC patients in the future.

Resolvin D1 reprograms energy metabolism to promote microglia to phagocytize neutrophils after ischemic stroke.

Neutrophil aggregation and clearance are important factors affecting neuroinflammatory injury during acute ischemic stroke. Emerging evidence suggests that energy metabolism is essential for microglial functions, especially microglial phagocytosis, which determines the degree of brain injury. Here, we demonstrate that Resolvin D1 (RvD1), a lipid mediator derived from docosahexaenic acid (DHA), promotes the phagocytosis of neutrophils by microglia, thereby reducing neutrophil accumulation in the brain and alleviating neuroinflammation in the ischemic brain. Further studies reveal that RvD1 reprograms energy metabolism from glycolysis to oxidative phosphorylation (OXPHOS), providing sufficient energy for microglial phagocytosis. Moreover, RvD1 enhances microglial glutamine uptake and stimulates glutaminolysis to support OXPHOS to boost ATP production depending on adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) activation. Overall, our results reveal that RvD1 reprograms energy metabolism to promote the microglial phagocytosis of neutrophils after ischemic stroke. These findings may guide perspectives for stroke therapy from modulating microglial immunometabolism.

Biodegradation of trace sulfonamide antibiotics accelerated by substrates across oxic to anoxic conditions during column infiltration experiments.

Frequent occurrence of trace organic contaminants in aquatic environments, such as sulfonamide antibiotics in rivers receiving reclaimed water, is concerning. Natural attenuation by soil and sediment is increasingly relied upon. In the case of riverbank filtration for water purification, the reliability of antibiotic attenuation has been called into question due to incomplete understanding of their degradation processes. This study investigated influence of substrates and redox evolution along infiltration path on biotransformation of sulfonamides. Eight sand columns (length: 28 cm) with a riverbed sediment layer at 3-8 cm were fed by groundwater-sourced tap water spiked with 1 µg/L of sulfadiazine (SDZ), sulfamethazine (SMZ), and sulfamethoxazole (SMX) each, with or without amendments of dissolved organic carbon (5 mg-C/L of 1:1 yeast and humics) or ammonium (5 mg-N/L). Two flow rates were tested over 120 days (0.5 mL/min and 0.1 mL/min). Iron-reducing conditions persisted in all columns for 27 days during the initial high flow period due to respiration of sediment organics, evolving to less reducing conditions until the subsequent low flow period to resume more reducing conditions. With surplus substrates, the spatial and temporal patterns of redox conditions differentiated among columns. The removal of SDZ and SMZ in effluents was usually low (15 ± 11%) even with carbon addition (14 ± 9%), increasing to 33 ± 23% with ammonium addition. By contrast, SMX removal was higher and more consistent among columns (46 ± 21%), with the maximum of 64 ± 9% under iron-reducing conditions. When sulfonamide removal was compared between columns for the same redox zones during infiltration, their enhancements were always associated with the availability of dissolved or particulate substrates, suggesting co-metabolism. Manipulation of the exposure time to optimal redox conditions with substrate amendments, rather than to simply prolong the overall residence time, is recommended for nature-based solutions to tackle target antibiotics.

Investigating the Clinical Characteristics and PITX3Mutations of a Large Chinese Family with Anterior Segment Mesenchymal Dysgenesis and Congenital Posterior Polar Cataract.

Objective: To investigate the clinical characteristics and pathogenic genetic mutations of a Chinese family with anterior segment mesenchymal dysgenesis and congenital posterior polar cataract. Methods: Through family investigation, the family members were examined via slit lamp anterior segment imaging and screened for eye and other diseases by eye B-ultrasound. Genetic test was performed on the blood samples of the fourth family generation (23 people) via whole exome sequencing (trio-WES) and Sanger sequencing. Results: Among the 36 members in four family generations, there were 11 living cases with different degrees of ocular abnormalities, such as cataracts, leukoplakia, and small cornea. All patients who received the genetic test had the heterozygous frameshift mutation c.640_656dup (p.G220Pfs∗95) on exon 4 of the PITX3 gene. This mutation was cosegregated with the clinical phenotypes in the family and thus might be one of the genetic factors that cause the corresponding ocular abnormalities in this family. Conclusion: The congenital posterior polar cataract with or without anterior interstitial dysplasia (ASMD) of this family was inherited in an autosomal dominant manner, and the frameshift mutation (c.640_656dup) in the PITX3 gene was the cause of ocular abnormalities observed in this family. This study is of great significance for guiding prenatal diagnosis and disease treatment.

Gadolinium retention in the ischemic cerebrum: Implications for pain, neuron loss, and neurological deficits.

PURPOSE: To investigate the effects of gadolinium (Gd) retention of macrocyclic (gadobutrol) or linear (gadopentetate) Gd-based contrast agents (GBCAs) on neuron loss, neurological deficits, and sensory behavior in mice with or without stroke. METHODS: Ninety C57BL/6 mice underwent sham (n = 36) or transient middle cerebral artery occlusion (tMCAO) (n = 54) surgery and then received intraperitoneal injections of 5.0 mmol/kg gadobutrol, 5.0 mmol/kg gadopentetate or saline (10 ml/kg/administration) per day for 3 consecutive days. The Gd concentration in the ischemic cerebrum was quantified by inductively coupled plasma mass spectrometry on Day 1 and Day 28 after the last injection (post-injection, p. i.). Neuron loss, glia activation and neurological deficits were assessed on Day 1 and 28 p. i. Sensory behavior was also assessed on Day 28 p. i. RESULTS: Gd concentrations were higher in the brains of tMCAO mice than in those of sham mice on Days 1 p. i. of both GBCAs (gadobutrol, p &lt; 0.05; gadopentetate, p &lt; 0.001) and 28 p. i of gadopentetate. (p &lt; 0.001). Sham or tMCAO mice injected with GBCAs showed no significant difference in neuron loss, glia activation, neurological deficits, brain atrophy, or hippocampus-dependent memory (all p &gt; 0.05). Both gadobutrol and gadopentetate induced mechanical and heat hyperalgesia in sham mice (all p &lt; 0.05). However, mechanical hyperalgesia but rather heat hyperalgesia was found in tMCAO mice with the highest force tested (1.0 g) and statistically significant in both paws (right and left) with gadopentetate only (p &lt; 0.05). CONCLUSIONS: Neither gadobutrol nor gadopentetate worsened neuron loss, glia activation, brain atrophy, neurological deficits, or hippocampus-dependent memory after tMCAO. However, GBCA administration induced mechanical hyperalgesia in sham and tMCAO mice although in the same level, which may be an important consideration for patients with central post-stroke pain and those who are sensitive to pain and about to receive multiple GBCA administrations.

Low FNDC5/Irisin expression is associated with aggressive phenotypes in gastric cancer.

Background: FNDC5 belongs to the family of proteins called fibronectin type III domain-containing which carry out a variety of functions. The expression of FNDC5 is associated with the occurrence and development of tumors. However, the role of FNDC5 in gastric cancer remains relatively unknown. Methods: In the research, the expression of FNDC5 and its value for the prognosis of gastric cancer patients were observed with the TCGA database and GEO datasets of gastric cancer patients. The role of FNDC5 in the regulation of gastric cancer cells proliferation, invasion, and migration was determined. WGCNA and Enrichment analysis was performed on genes co-expressed with FNDC5 to identify potential FNDC5-related signaling pathways. Meanwhile, the LASSO Cox regression analysis based on FNDC5-related genes develops a risk score to predict the survival of gastric cancer patients. Results: The expression of FNDC5 was decreased in gastric cancer tissues compared to normal gastric tissues. However, survival analysis indicated that lower FNDC5 mRNA levels were associated with better overall survival and disease-free survival in gastric cancer patients. Meanwhile, a significant negative correlation was found between FNDC5 and the abundance of CD4+ memory T cells in gastric cancer. In vitro overexpression of FNDC5 inhibits the migration and invasion of gastric cancer cells, without affecting proliferation. Finally, A two-gene risk score module based on FNDC5 co-expressed gene was built to predict the overall clinical ending of patients. Conclusion: FNDC5 is low expressed in gastric cancer and low FNDC5 predicts a better prognosis. The better prognosis of low FNDC5 expression may be attributed to the increased number of CD4+ memory activated T-cell infiltration in tumors, but the exact mechanism of the effect needs to be further explored. Overexpressing FNDC5 inhibits the invasion and migration of gastric cancer but does not affect proliferation. At last, we constructed a clinical risk score model composed of two FNDC5-related genes, and this model may help lay the foundation for further in-depth research on the individualized treatment of gastric cancer patients.

High DAPK1 Expression Promotes Tumor Metastasis of Gastric Cancer.

Gastric cancer (GC) is a common upper gastrointestinal tumor. Death-associated protein kinase (DAPK1) was found to participate in the development of various malignant tumors. However, there are few reports on DAPK1 in gastric cancer. In this study, the TCGA and GEO datasets were used to explore the expression and role of DAPK1 in gastric cancer. The functions of DAPK1 in gastric cancer were determined by proliferation, migration and invasion assays. In addition, genes co-expressed with DAPK1 in gastric cancer were estimated through the WGCNA and correlation analysis. A DAPK1-related gene prognostic model was constructed using the Cox regression and lasso analyses. The expression of DAPK1 was significantly up-regulated in gastric cancer tissues. Kaplan-Meier analysis showed that low expression of DAPK1 was a favorable prognostic factor of overall survival and disease-free survival for gastric cancer patients. Functional experiments demonstrated that DAPK1 can promote the migration and invasion of gastric cancer cells. WGCNA, correlation analysis, Cox regression, and lasso analyses were applied to construct the DAPK1-related prognostic model. The prognostic value of this prognostic model of DAPK1-related genes was further successfully validated in an independent database. Our results indicated that DAPK1 can promote gastric cancer cell migration and invasion and established four DAPK1-related signature genes for gastric cancer that could independently predict the survival of GC patients.

Iptakalim improves cerebral microcirculation in mice after ischemic stroke by inhibiting pericyte contraction.

Pericytes are present tight around the intervals of capillaries, play an essential role in stabilizing the blood-brain barrier, regulating blood flow and immunomodulation, and persistent contraction of pericytes eventually leads to impaired blood flow and poor clinical outcomes in ischemic stroke. We previously show that iptakalim, an ATP-sensitive potassium (K-ATP) channel opener, exerts protective effects in neurons, and glia against ischemia-induced injury. In this study we investigated the impacts of iptakalim on pericytes contraction in stroke. Mice were subjected to cerebral artery occlusion (MCAO), then administered iptakalim (10 mg/kg, ip). We showed that iptakalim administration significantly promoted recovery of cerebral blood flow after cerebral ischemia and reperfusion. Furthermore, we found that iptakalim significantly inhibited pericytes contraction, decreased the number of obstructed capillaries, and improved cerebral microcirculation. Using a collagen gel contraction assay, we demonstrated that cultured pericytes subjected to oxygen-glucose deprivation (OGD) consistently contracted from 3 h till 24 h during reoxygenation, whereas iptakalim treatment (10 µM) notably restrained pericyte contraction from 6 h during reoxygenation. We further showed that iptakalim treatment promoted K-ATP channel opening via suppressing SUR2/EPAC1 complex formation. Consequently, it reduced calcium influx and ET-1 release. Taken together, our results demonstrate that iptakalim, targeted K-ATP channels, can improve microvascular disturbance by inhibiting pericyte contraction after ischemic stroke. Our work reveals that iptakalim might be developed as a promising pericyte regulator for treatment of stroke.

Microorganisms as bio-filters to mitigate greenhouse gas emissions from high-altitude permafrost revealed by nanopore-based metagenomics.

The distinct climatic and geographical conditions make high-altitude permafrost on the Tibetan Plateau suffer more severe degradation than polar permafrost. However, the microbial responses associated with greenhouse gas production in thawing permafrost remain obscured. Here we applied nanopore-based long-read metagenomics and high-throughput RNA-seq to explore microbial functional activities within the freeze-thaw cycle in the active layers of permafrost at the Qilian Mountain. A bioinformatic framework was established to facilitate phylogenetic and functional annotation of the unassembled nanopore metagenome. By deploying this strategy, 42% more genera could be detected and 58% more genes were annotated to nitrogen and methane cycle. With the aid of such enlarged resolution, we observed vigorous aerobic methane oxidation by Methylomonas, which could serve as a bio-filter to mitigate CH4 emissions from permafrost. Such filtering effect could be further consolidated by both on-site gas phase measurement and incubation experiment that CO2 was the major form of carbon released from permafrost. Despite the increased transcriptional activities of aceticlastic methanogenesis pathways in the thawed permafrost active layer, CH4 generated during the thawing process could be effectively consumed by the microbiome. Additionally, the nitrogen metabolism in permafrost tends to be a closed cycle and active N2O consumption by the topsoil community was detected in the near-surface gas phase. Our findings reveal that although the increased thawed state facilitated the heterotrophic nitrogen and methane metabolism, effective microbial methane oxidation in the active layer could serve as a bio-filter to relieve the overall warming potentials of greenhouse gas emitted from thawed permafrost.

Oridonin prevents oxidative stress-induced endothelial injury via promoting Nrf-2 pathway in ischaemic stroke.

Oridonin, a natural diterpenoid compound extracted from a Chinese herb, has been proved to exert anti-oxidative stress effects in various disease models. The aim of the present study was to investigate the protective effects of oridonin on oxidative stress-induced endothelial injury in ischaemic stroke. We found oridonin repaired blood-brain barrier (BBB) integrity presented with upregulation of tight junction proteins (TJ proteins) expression, inhibited the infiltration of periphery inflammatory cells and neuroinflammation and thereby reduced infarct volume in ischaemic stroke mice. Furthermore, our results showed that oridonin could protect against oxidative stress-induced endothelial injury via promoting nuclear translocation of nuclear factor-erythroid 2 related factor 2 (Nrf-2). The specific mechanism could be the activation of AKT(Ser473)/GSK3ß(Ser9)/Fyn signalling pathway. Our findings revealed the therapeutic effect and mechanism of oridonin in ischaemic stroke, which provided fundamental evidence for developing the extracted compound of Chinese herbal medicine into an innovative drug for ischaemic stroke treatment.

Extracellular vesicles derived from LPS-preconditioned human synovial mesenchymal stem cells inhibit extracellular matrix degradation and prevent osteoarthritis of the knee in a mouse model.

BACKGROUND: Previous studies report that lipopolysaccharide (LPS)-preconditioned mesenchymal stem cells have enhanced trophic support and improved regenerative and repair properties. Extracellular vesicles secreted by synovial mesenchymal stem cells (EVs) can reduce cartilage damage caused by osteoarthritis (OA). Previous studies show that extracellular vesicles secreted by LPS-preconditioned synovial mesenchymal stem cells (LPS-pre EVs) can improve the response to treatment of osteoarthritis (OA). This study sought to explore effects of LPS-pre EVs on chondrocyte proliferation, migration, and chondrocyte apoptosis, as well as the protective effect of LPS-pre EVs on mouse articular cartilage. METHODS: Chondrocytes were extracted to explore the effect of LPS-pre EVs on proliferation, migration, and apoptosis of chondrocytes. In addition, the effect of LPS-pre EVs on expression level of important proteins of chondrocytes was explored suing in vitro experiments. Further, intraarticular injection of LPS-pre EVs was performed on the destabilization of the medial meniscus (DMM)-induced mouse models of OA to explore the therapeutic effect of LPS-pre EVs on osteoarthritis in vivo. RESULTS: Analysis showed that LPS-pre EVs significantly promoted proliferation and migration of chondrocytes and inhibited the apoptosis of chondrocytes compared with PBS and EVs. Moreover, LPS-pre EVs inhibited decrease of aggrecan and COL2A1 and increase of ADAMTS5 caused by IL-1ß through let-7b. Furthermore, LPS-pre EVs significantly prevented development of OA in DMM-induced mouse models of OA. CONCLUSIONS: LPS pretreatment is an effective and promising method to improve therapeutic effect of extracellular vesicles secreted from SMSCs on OA.

Reduction of iron (hydr)oxide-bound arsenate: Evidence from high depth resolution sampling of a reducing aquifer in Yinchuan Plain, China.

Sediment in fluvial-deltaic plains with high-As groundwater is heterogenous but its characterization of As and Fe oxidation states lacks resolution, and is rarely attempted for aqueous and solid phases simultaneously. Here, we pair high-resolution (> 1 sample/meter) Fe extended fine-structure spectroscopy (EXAFS, n = 40) and As X-ray absorption near-edge spectroscopy (XANES, n = 49) with groundwater composition and metagenomics measurements for two sediment cores and their associated wells (n = 8) from the Yinchuan Plain in northwest China. At shallower depths, nitrate and Mn/Fe reducing sediment zones are fine textured, contain 9.6 ± 5.6 mg kg-1 of As(V) and 2.3 ± 2.7 mg kg-1 of As(III) with 9.1 ± 8.1 g kg-1 of Fe(III) (hydr)oxides, with bacterial genera capable of As and Fe reduction identified. In four deeper 10-m sections, sulfate-reducing sediments are coarser and contain 2.6 ± 1.3 mg kg-1 of As(V) and 1.1 ± 1.0 mg kg-1 of As(III) with 3.2 ± 2.6 g kg-1 of Fe(III) (hydr)oxides, even though groundwater As concentrations can exceed 200 µg/L, mostly as As(III). Super-enrichment of sediment As (42-133 mg kg-1, n = 7) at shallower depth is due to redox trapping during past groundwater discharge. Active As and Fe reduction is supported by the contrast between the As(III)-dominated groundwater and the As(V)-dominated sediment, and by the decreasing sediment As(V) and Fe(III) (hydr)oxides concentrations with depth.

Exploration of gastric neuroendocrine carcinoma (GNEC) specific signaling pathways involved in chemoresistance via transcriptome and in vitro analysis.

Gastric neuroendocrine carcinoma (GNEC) is rare cancer detected in the stomach. Previously, we demonstrated that the poorer prognosis of GNEC patients compared with gastric adenocarcinoma (GAC) patients was probably due to the lack of response to chemotherapy. Thus, it is crucial to study the specific GNEC gene expression pattern and investigate chemoresistance mechanism of GNEC. The transcriptome of GNEC patients was compared with that of GAC patients using RNA-seq. The KEGG analysis was employed to explore the specific differential expression gene function enrichment pattern. In addition, the transcriptomes of two GNEC cell lines, ECC10 and ECC12, were also compared with those of two GAC cell lines, MGC-803 and AGS, using RNA-seq. Comparing patient samples and cell lines transcriptome data, we try to uncover the potential targets and pathways which may affect the chemoresistance of GNEC. By combing all transcriptome data, we identified 22 key genes that were specifically up-regulated in GNEC. This panel of genes probably involves in the chemoresistance of GNEC. From our current experimental data, NeuroD1, one of the 22 genes, is associated with the prognosis of GNEC patients. Knockdown of NeuroD1 enhanced the sensitivity to irinotecan of GNEC cell lines. Our research sheds light in identifying a panel of novel therapeutic target specifically for GNEC clinical treatment which has not been reported before.