Exosomal miR-4745-5p/3911 from N2-polarized tumor-associated neutrophils promotes gastric cancer metastasis by regulating SLIT2.

Tumor cells remodel the phenotype and function of tumor microenvironment (TME) cells to favor tumor progression. Previous studies have shown that neutrophils in TME are polarized to N2 tumor-associated neutrophils (TANs) by tumor derived factors, thus promoting tumor growth and metastasis, angiogenesis, therapy resistance, and immunosuppression. Exosomes act as critical intercellular messengers in human health and diseases including cancer. So far, the biological roles of exosomes from N2 TANs in gastric cancer have not been well characterized. Herein, we represented the first report that exosomes from N2 TANs promoted gastric cancer metastasis in vitro and in vivo. We found that exosomes from N2 TANs transferred miR-4745-5p/3911 to gastric cancer cells to downregulate SLIT2 (slit guidance ligand 2) gene expression. Adenovirus-mediated overexpression of SLIT2 reversed the promotion of gastric cancer metastasis by N2 TANs derived exosomes. We further revealed that gastric cancer cells induced glucose metabolic reprogramming in neutrophils through exosomal HMGB1 (high mobility group protein B1)/NF-κB pathway, which mediated neutrophil N2 polarization and miR-4745-5p/3911 upregulation. We further employed ddPCR (droplet digital PCR) to detect the expression of miR-4745-5p/3911 in N2 TANs exosomes from human serum samples and found their increased levels in gastric cancer patients compared to healthy controls and benign gastric disease patients. Conclusively, our results indicate that N2 TANs facilitate cancer metastasis via regulation of SLIT2 in gastric cancer cells by exosomal miR-4745-5p/3911, which provides a new insight into the roles of TME cells derived exosomes in gastric cancer metastasis and offers a potential biomarker for gastric cancer diagnosis.

Circ6834 suppresses non-small cell lung cancer progression by destabilizing ANHAK and regulating miR-873-5p/TXNIP axis.

BACKGROUND: Circular RNAs (circRNAs) play important roles in cancer progression and metastasis. However, the expression profiles and biological roles of circRNAs in non-small cell lung cancer (NSCLC) remain unclear. METHODS: In this study, we identified a novel circRNA, hsa_circ_0006834 (termed circ6834), in NSCLC by RNA-seq and investigated the biological role of circ6834 in NSCLC progression in vitro and in vivo. Finally, the molecular mechanism of circ6834 was revealed by tagged RNA affinity purification (TRAP), western blot, RNA immunoprecipitation, dual luciferase reporter gene assays and rescue experiments. RESULTS: Our results showed that circ6834 was downregulated in NSCLC tumor tissues and cell lines. Circ6834 overexpression inhibited NSCLC cell growth and metastasis both in vitro and in vivo, while circ6834 knockdown had the opposite effect. We found that TGF-ß treatment decreased circ6834 expression, which was associated with the QKI reduction in NSCLC cells and circ6834 antagonized TGF-ß-induced EMT and metastasis in NSCLC cells. Mechanistically, circ6834 bound to AHNAK protein, a key regulator of TGF-ß/Smad signaling, and inhibited its stability by enhancing TRIM25-mediated ubiquitination and degradation. In addition, circ6834 acted as a miRNA sponge for miR-873-5p and upregulated TXNIP gene expression, which together inactivated the TGF-ß/Smad signaling pathway in NSCLC cells. CONCLUSION: In conclusion, circ6834 is a tumor-suppressive circRNA that inhibits NSCLC progression by forming a negative regulatory feedback loop with the TGF-ß/Smad signaling pathway and represents a novel therapeutic target for NSCLC.

Lipid droplets-related Perilipin-3: potential immune checkpoint and oncogene in oral squamous cell carcinoma.

BACKGROUND: Lipid droplets (LDs) as major lipid storage organelles are recently reported to be innate immune hubs. Perilipin-3 (PLIN3) is indispensable for the formation and accumulation of LDs. Since cancer patients show dysregulated lipid metabolism, we aimed to elaborate the role of LDs-related PLIN3 in oral squamous cell carcinoma (OSCC). METHODS: PLIN3 expression patterns (n = 87), its immune-related landscape (n = 74) and association with B7-H2 (n = 51) were assessed by immunohistochemistry and flow cytometry. Real-time PCR, Western blot, Oil Red O assay, immunofluorescence, migration assay, spheroid-forming assay and flow cytometry were performed for function analysis. RESULTS: Spotted LDs-like PLIN3 staining was dominantly enriched in tumor cells than other cell types. PLIN3high tumor showed high proliferation index with metastasis potential, accompanied with less CD3+CD8+ T cells in peripheral blood and in situ tissue, conferring immunosuppressive microenvironment and shorter postoperative survival. Consistently, PLIN3 knockdown in tumor cells not only reduced LD deposits and tumor migration, but benefited for CD8+ T cells activation in co-culture system with decreased B7-H2. An OSCC subpopulation harbored PLIN3highB7-H2high tumor showed more T cells exhaustion, rendering higher risk of cancer-related death (95% CI 1.285-6.851). CONCLUSIONS: LDs marker PLIN3 may be a novel immunotherapeutic target in OSCC.

Annexin A5 is a novel prognostic biomarker in oral squamous cell carcinoma.

BACKGROUND: ANXA5, a notable tumor marker, displays irregular expression in diverse solid cancers, and links to local recurrence and metastasis rates. We aimed study the expression of ANXA5 in oral squamous cell carcinoma (OSCC) and its diagnostic and prognostic values. METHODS: 520 head and neck squamous cell carcinoma (HNSCC) patients in TCGA database and 124 OSCC patients in Nanjing stomatology hospital were enrolled in our study. Immunohistochemical analyses were performed using ANXA5 antibodies. Chi-square test was used to analyze the clinicopathological features. Survival rates were determined using the Kaplan-Meier method and log-rank test. RESULTS: Our results showed significantly elevated ANXA5 at the gene and protein levels in HNSCC and OSCC compared to non-tumor tissues. Histopathologically, ANXA5 was broadly present in OSCC tumor cells and fibroblast-like cells but absent in tumor-infiltrating lymphocytes, particularly at the invasive tumor front. Patients exhibiting high ANXA5 expression in these cells demonstrated poor differentiation, aggressive invasion patterns, and heightened lymph node metastasis risk, contributing to poorer postoperative outcomes. Remarkably, ANXA5 in fibroblast-like cells emerged as an independent risk factor impacting survival in OSCC patients. Gene set enrichment analysis (GSEA) highlighted ANXA5's involvement in key pathways like epithelial-mesenchymal transformation (EMT), TGF-beta signaling, and hypoxia, which correlated with adverse clinical outcomes in OSCC. CONCLUSION: ANXA5 emerges as a significant prognostic biomarker for OSCC, potentially influencing its metastasis via the EMT pathway.

Neonicotinoid insecticides in waters of Hongze lake, the largest impounded lake on the South-to-North water diversion project, China: Implications for environmental and public health.

Contamination by neonicotinoid (NEO) insecticides in surface waters is a global problem. Nevertheless, the occurrence of NEOs in lakes is not well known. Hongze Lake, the largest impounded lake on the Eastern Route of the South-to-North Water Diversion Project, was selected to investigate the distribution, ecological risks, and health risks of NEOs. Water samples from the lake and nearby rivers were collected and analyzed for 8 widely used NEOs in three seasons. The results indicated the average total NEO concentration in summer, winter, and spring was 222, 211, and 244 ng L-1 for the river water, and 265, 213, and 181 ng L-1 for the lake water, respectively, with no statistical seasonal difference. For the river water, the highest total NEO concentration in the three seasons was observed in the Andong River. For the lake water, the total NEO concentrations in summer were relatively high in sites near the inflow river estuaries due to the high riverine inputs during the flood period. The spatial difference in NEO concentration was relatively low in winter, which may be related to the wind-driven lake current. The seasonal variation in NEO compositions in the lake was generally similar to that in the river, indicating riverine input was the important source for the lake. Huai River was the largest contributor to the NEO inputs to the lake, and Sanhe Gate was the major output pathway. Clothianidin and imidacloprid in the river and lake water would produce moderate acute ecological risks in summer. Thus, the usage of the above two NEOs should be decreased or restricted. For integral NEO risks, 53% and 58% of the river and lake water sites exceeded the acute ecological threshold, respectively. Health risk assessment suggested drinking the water obtained from the lake would not produce a negative impact on public health.

Development of a super-hydrophilic anaerobic tube for the optimization of platelet-rich fibrin.

Horizontal platelet-rich fibrin (H-PRF) contains a variety of bioactive growth factors and cytokines that play a key role in the process of tissue healing and regeneration. The blood collection tubes used to produce Solid-PRF (plasmatrix (PM) tubes) have previously been shown to have a great impact on the morphology, strength and composition of the final H-PRF clot. Therefore, modification to PM tubes is an important step toward the future optimization of PRF. To this end, we innovatively modified the inner wall surface of the PM tubes with plasma and adjusted the gas environment inside the PM tubes to prepare super-hydrophilic anaerobic plasmatrix tubes (SHAP tubes). It was made anaerobic for the preparation of H-PRF with the aim of improving mechanical strength and bioactivity. The findings demonstrated that an anaerobic environment stimulated platelet activation within the PRF tubes. After compression, the prepared H-PRF membrane formed a fibrous cross-linked network with high fracture strength, ideal degradation characteristics, in addition to a significant increase in size. Thereafter, the H-PRF membranes prepared by the SHAP tubes significantly promoted collagen synthesis of gingival fibroblast and the mineralization of osteoblasts while maintaining excellent biocompatibility, and advantageous antibacterial properties. In conclusion, the newly modified PRF tubes had better platelet activation properties leading to better mechanical strength, a longer degradation period, and better regenerative properties in oral cell types including gingival fibroblast and alveolar osteoblasts. It also improves the success rate of H-PRF preparation in patients with coagulation dysfunction and expands the clinical application scenario.

Why was the study done?   Direct anaerobic environment effects on fibrin formation have been insufficiently studied.The effect of hydrophilic change caused by nitrogen plasma treatment on H-PRF coagulation has not been fully studied.Optimal preparation of H-PRF in patients with poor coagulation function was needed in clinical application.What is new?  The coagulation of H-PRF correlated with the level of dissolved oxygen concentrations. Anaerobic environment significantly accelerates fibrin formation and platelet activation.Nitrogen plasma treatment can remarkably enhance the hydrophilicity of the inner surface of glass blood collecting tubes, thereby promoting the activation of platelets and the formation of fibrin network.The H-PRF prepared in the tubes with anaerobic environment and hydrophilic surface showed high fracture strength, promoted collagen synthesis of gingival fibroblast and the mineralization of osteoblasts.What is the impact?  The work is aimed at developing super-hydrophilic anaerobic plasmatrix tubes (SHAP tubes) for studying gas environment and hydrophilicity participation in fibrin formation in H-PRF preparation and investigating the influence of platelet activation in the anaerobic environment.This study provides a successful trial to convert the physiological process into biotechnological application. The SHAP tubes proposed within this article was an effective versatile H-PRF preparation device, which provided a promising alternative for tissue engineering.

Interaction between CAFs and apoptotic cancer cells promotes OSCC proliferation via STING signaling.

BACKGROUND: Apoptosis can fuel oncogenesis by the education of surrounding stromal cells. However, the function of cancer-associated fibroblasts (CAFs), which interacted with apoptotic cancer cells, in oral squamous cell carcinoma (OSCC) progression is still unknown. OBJECTIVES: This study aimed to explore the prognostic value of apoptosis and the biological effects of CAFs, interacted with apoptotic cancer cells, on OSCC. METHODS: A total of 166 samples from OSCC patients were stained via TUNEL reaction to evaluate the correlation between apoptosis and clinical characteristics. Cell viability and proliferation were assessed through flow cytometry and CCK-8 assays, respectively. Levels of mRNA and protein were examined through qRT-PCR, western blot and immunofluorescence. RESULTS: Higher percentage of apoptotic cancer cells in OSCC positively correlated with more Ki67+ cells and predicted poor clinical outcomes. Conditioned medium from CAFs exposed to apoptotic cancer cells significantly facilitated cell proliferation. Co-culture CAFs with apoptotic cancer cells dampened the phosphorylation of STING/IRF3 signaling, as well as the production of type I interferon, which was required for the inhibition of OSCC cell proliferation. CONCLUSION: These results demonstrate the interplay between apoptotic cancer cells and CAFs promotes OSCC proliferation via STING signaling, identifying a potential therapy targeted CAFs surrounded with apoptotic cancer cells for OSCC.

Tailored Exfoliation of Polymeric Carbon Nitride for Photocatalytic H2O2 Production and CH4 Valorization Mediated by O2 Activation.

The exfoliation of bulk C3N4 (BCN) into ultrathin layered structure is an effective strategy to boost photocatalytic efficiency by exposing interior active sites and accelerating charge separation and transportation. Herein, we report a novel nitrate anion intercalation-decomposition (NID) strategy that is effective in peeling off BCN into few-layer C3N4 (fl-CN) with tailored thickness down to bi-layer. This strategy only involves hydrothermal treatment of BCN in diluted HNO3 aqueous solution, followed by pyrolysis at various temperatures. The decomposition of the nitrate anions not only exfoliates BCN and changes the band structure, but also incorporates oxygen species onto fl-CN, which is conducive to O2 adsorption and hence relevant chemical processes. In photocatalytic O2 reduction under visible light irradiation, the H2O2 production rate over the optimal fl-CN-530 catalyst is 952 µmol g-1 h-1, which is 8.8 times that over BCN. More importantly, under full arc irradiation and in the absence of hole scavenger, CH4 can be photocatalytically oxidized by on-site formed H2O2 and active oxygen species to generate value-added C1 oxygenates with high selectivity of 99.2 % and record-high production rate of 1893 µmol g-1 h-1 among the metal-free C3N4-based photocatalysts.

LINC02159 promotes non-small cell lung cancer progression via ALYREF/YAP1 signaling.

Lung cancer is the leading cause of cancer-related deaths worldwide. Long non-coding RNAs (lncRNAs) have emerged as key regulators of cancer development and progression, and as promising biomarkers for the diagnosis and prognosis of cancer. In this study, we identified a new lncRNA (LINC02159) that was upregulated in the tumor tissues and serum of non-small cell lung cancer (NSCLC) patients. We demonstrated that knockdown of LINC02159 inhibited NSCLC cell proliferation, migration, and invasion, but induced cell apoptosis and cell cycle arrest in vitro and retarded tumor growth in vivo, while overexpression of LINC02159 led to the opposite effect. We discovered that LINC02159 was highly correlated with cancer growth and metastasis-related pathways by using transcriptomic analysis and that YAP1 was a potential target gene of LINC02159. Mechanistically, LINC02159 bound to the Aly/REF export factor (ALYREF) to enhance the stability of YAP1 messenger RNA (mRNA) via m5C modification, which led to the overexpression of YAP1 and the activation of the Hippo and ß-catenin signaling pathways in NSCLC cells. Rescue experiments showed that LINC01259 promoted NSCLC progression in a YAP1- and ALYREF-dependent manner. In conclusion, LINC02159 plays an oncogenic role in NSCLC progression by regulating ALYREF/YAP1 signaling, and it has the potential to be utilized as a diagnostic marker and therapeutic target for NSCLC.

SALL4 promotes angiogenesis in gastric cancer by regulating VEGF expression and targeting SALL4/VEGF pathway inhibits cancer progression.

BACKGROUND: Spalt-like protein 4 (SALL4) is a stemness-related transcription factor whose abnormal re-expression contributes to cancer initiation and progression. However, the role of SALL4 in cancer angiogenesis remains unknown. METHODS: Analyses of clinical specimens via TCGA datasets were performed to determine the expression level and clinical significance of SALL4 in STAD (Stomach Adenocarcinoma). SALL4 knockdown, knockout, and overexpression were achieved by siRNA, CRISPR/Cas9, and plasmid transfection. The effects of conditioned medium (CM) from SALL4 knockdown or overexpression of gastric cancer cells on endothelial cell proliferation, migration, and tube formation were investigated by CCK-8 assay, transwell migration assay, and tube formation assay. The regulation of VEGF gene expression by SALL4 was studied by qRT-PCR, western blot, chromatin immunoprecipitation (ChIP) assay, and electrophoretic mobility shift assay (EMSA). Engineered exosomes from 293T cells loaded with si-SALL4-B and thalidomide were produced to test their therapeutic effect on gastric cancer progression. RESULTS: SALL4 expression was increased in STAD and positively correlated with tumor progression and poor prognosis. SALL4-B knockdown or knockout decreased while over-expression increased the promotion of human umbilical vein endothelial cells (HUVEC) cell proliferation, migration, and tube formation by gastric cancer cell-derived CM. Further investigation revealed a widespread association of SALL4 with angiogenic gene transcription through the TCGA datasets. Additionally, SALL4-B knockdown reduced, while over-expression enhanced the expression levels of VEGF-A, B, and C genes. The results of ChIP and EMSA assays indicated that SALL4 could directly bind to the promoters of VEGF-A, B, and C genes and activate their transcription, which may be associated with increased histone H3-K79 and H3-K4 modifications in their promoter regions. Furthermore, si-SALL4-B and thalidomide-loaded exosomes could be efficiently uptaken by gastric cancer cells and significantly reduced SALL4-B and Vascular Endothelial Growth Factor (VEGF) expression levels in gastric cancer cells, thus inhibiting the pro-angiogenic role of their derived CM. CONCLUSION: These findings suggest that SALL4 plays an important role in angiogenesis by transcriptionally regulating VEGF expression. Co-delivery of the functional siRNA and anticancer drug via exosomes represents a useful approach to inhibiting cancer angiogenesis by targeting SALL4/VEGF pathway.

Nanocages and cell-membrane display technology as smart biomaterials.

Gold nanocages (AuNCs) have been invented and developed over two decades as biomaterial in clinical medicine with great application potential. AuNCs have a characteristic structure of porous walls with hollow interior and a compact size. This makes it possible for them to transport biomolecules or drugs with the advantages of their photothermal effects that could help further destroy germs or tumors while also regulating the release of drugs inside. Furthermore, their bioactivity and application can be broadened by using cell-membrane display technology. AuNCs have shown tremendous potential in antibacterial activity, inflammation modulation, and tissue regeneration, which is required in periodontitis and peri-implantitis treatment. Thus, this article provides an overview of AuNCs synthesis, characteristics, surface modifications, and clinical applications, aiming to serve as a reference for the design and fabrication of AuNCs-based smart materials for periodontal or peri-implant application.

Green synthesized hydroxyapatite for efficient immobilization of cadmium in weakly alkaline environment.

The development of cost-effective passivators for the remediation of heavy metal-contaminated soils has been a research hotspot and an unsolved challenge. Herein, a novel hydroxyapatite (GSCH) was synthesized by co-precipitating distiller effluent-derived Ca with (NH4)2HPO4 using straw-derived dissolved organic matter (S-DOM) as the dispersant. Batch adsorption experiments and soil incubation tests were performed to assess the immobilization efficiency of GSCH for Cd in weakly alkaline environments. As a result, GSCH showed an excellent adsorption efficiency to Cd with a maximum adsorption amount of ∼222 mg g-1, which was fairly competitive compared to other similar previously materials reported. The kinetic data indicated that the adsorption of Cd on GSCH was a chemical and irreversible process, while the thermodynamic data revealed a spontaneous (ΔG° < 0) and endothermic (ΔH° > 0) adsorption process. Based on mechanism analysis, both physisorption (e.g., electrostatic attraction and pore filling) and chemisorption (e.g., ion exchange and complexation) were responsible for Cd adsorption on GSCH. Particularly, the incorporated S-DOM and hydroxyapatite phase in GSCH acted synergistically in the adsorption process. The incubation results showed that GSCH application could significantly reduce the bioavailability, phytoavailability and bioaccessibility of Cd in soil by 48.4%-57.8%, 20.4%-28.6% and 12.6%-24.0%, respectively. Moreover, GSCH application also improved soil bacterial communities and enhanced soil nutrient availability. Overall, this is the first study to demonstrate the potential application value of GSCH in Cd immobilization, providing promising insights into the development of green and cost-effective hydroxyapatite-based passivators for the remediation of heavy metal-contaminated soils.

Effects of cancer-associated fibroblasts deletion using HSVtk suicide system in OSCC.

OBJECTIVE: To evaluate the biological characteristics of oral cancer cells co-cultured with cancer-associated fibroblasts (CAFs)-HSVtk and to assess the reliability of the CAFs-HSVtk suicide system in a co-culture model. METHODS: CAFs were lentivirus-transfected with PCDH-HSVtk. Ganciclovir (GCV) was added and the survival rates of the CAFs-HSVtk were measured. In parallel with the selective elimination of CAFs, comparison was made of the effects of CAF-HSVtk on tumor cell proliferation/migration in a CAFs-tumor co-cultural system. Cell death of co-cultured oral cancer cells was evaluated by flow cytometry. RESULTS: Q-PCR analysis showed that the expression of HSVtk in the CAFs-HSVtk group was significantly higher than in the control group (p < 0.01). The survival rates of CAFs-HSVtk with GCV were significantly reduced (p < 0.01). Following selective depletion of CAFs-HSVtk, the growth and migration rates of oral cancer cells co-cultured with CAFs-HSVtk were reduced in a mixture ratio of 1:2 (p < 0.01, p < 0.01). CONCLUSIONS: Enhanced proliferation and migration rates of oral cancer cells in co-culture were seriously impaired after deleting CAFs using the HSVtk suicide system, while oral tumor cell death was not affected. Therefore, CAFs-HSVtk can be utilized as a valid model for CAF signature identification.

The new advance of SALL4 in cancer: Function, regulation, and implication.

SALL4 (split-like protein 4) is a member of the mammalian homologs of the Drosophila homoeotic gene spalt (sal) and acts as a zinc finger transcription factor to govern the self-renewal and pluripotency of embryonic stem cells. SALL4 expression gradually decreases during development and is even absent in most adult tissues. However, increasing evidence suggests that SALL4 expression is restored in human cancers and its aberrant expression is associated with the progression of many hematopoietic malignancies and solid tumors. The potent roles of SALL4 in regulating cancer cell proliferation, apoptosis, metastasis, and drug resistance have been reported. SALL4 plays a dual role in epigenetic modulation by acting as either an activator or a repressor of its target genes. Furthermore, SALL4 interacts with other partners to control the expression of many downstream genes and the activation of various key signaling transduction pathways. SALL4 is considered as a promising diagnostic and prognostic biomarker and therapeutic target for cancer. In this review, we highlighted the major advances in the roles and mechanisms of SALL4 in cancer and the therapeutic strategies for targeting SALL4 to treat cancer.

An Illustration of FY-3E GNOS-R for Global Soil Moisture Monitoring.

An effective soil moisture retrieval method for FY-3E (Fengyun-3E) GNOS-R (GNSS occultation sounder II-reflectometry) is developed in this paper. Here, the LAGRS model, which is totally oriented for GNOS-R, is employed to estimate vegetation and surface roughness effects on surface reflectivity. Since the LAGRS (land surface GNSS reflection simulator) model is a space-borne GNSS-R (GNSS reflectometry) simulator based on the microwave radiative transfer equation model, the method presented in this paper takes more consideration on the physical scattering properties for retrieval. Ancillary information from SMAP (soil moisture active passive) such as the vegetation water content and the roughness coefficient are investigated for the final algorithm's development. At first, the SR (surface reflectivity) data calculated from GNOS-R is calculated and then calibrated, and then the vegetation roughness factor is achieved and used to eliminate the effects on both factors. After receiving the Fresnel reflectivity, the corresponding soil moisture estimated from this method is retrieved. The results demonstrate good consistency between soil moisture derived from GNOS-R data and SMAP soil moisture, with a correlation coefficient of 0.9599 and a root mean square error of 0.0483 cm3/cm3. This method succeeds in providing soil moisture on a global scale and is based on the previously developed physical LAGRS model. In this way, the great potential of GNOS-R for soil moisture estimation is presented.

Disentangling the effects of phosphorus loading on food web stability in a large shallow lake.

Excessive nutrient loads reduce ecosystem resilience, resulting in fundamental changes in ecosystem structure and function when exceeding a certain threshold. However, quantitative analysis of the processes by which nutrient loading affects ecosystem resilience requires further exploration. Food web stability is at the heart of ecosystem resilience. In this study, we simulated the dynamics of the food web under different phosphorus loads for Lake Baiyangdian using the PCLake model and calculated the food web stability. Our results showed that there was a good correspondence between the food web stability and ecosystem state response to phosphorus loads. This relationship confirmed that food web stability could be regarded as a signal for the state transition in a real lake ecosystem. Moreover, our estimates suggested that food web stability was influenced only by several functional groups and their interaction strength. Diatoms and zooplankton were the key functional groups that affected food web stability. Phosphorus loads alter the distribution of functional group biomass, which in turn affects energy delivery and, ultimately, the stability of the food web. Corresponding to functional groups, the interactions among zooplankton, diatoms and detritus had the greatest impact, and the interaction strength of the three was positively correlated with food web stability. Overall, our study explained that food-web stability was critical to characterize ecosystem resilience response to external disturbances and can be turned into a scientific tool for lake ecosystem management.

Effect of thermal manipulation on the biological and mechanical characteristics of horizontal platelet rich fibrin membranes.

BACKGROUD: Regardless of application scenarios, proper mechanical characteristics and degradation properties are prerequisites for horizontal platelet rich fibrin (H-PRF) to manifest its ability. Among the methods used to modify PRF, thermal manipulation is promising as it is easy to handle without adding extra additives. Yet there is no consensus on optimal temperature treatment. This study aimed to investigate the effects of heating on the biological and mechanical characteristics of H-PRF and explore the optimum heating temperature for H-PRF thermal treatment. METHODS: We employed a series of temperature gradients, room temperature, 50℃, 75℃, 90℃, 105℃. The microstructure and the mechanical properties were recorded by Scanning Electron Microscope (SEM) and tensile strength tests respectively. The degradation rate of H-PRF membranes was examined by digestion assay with plasmin and trypsin. The viability of cells within H-PRF membranes and the proliferation of osteoblasts cultured with extracts from different H-PRF groups was evaluated using CCK-8 assays. RESULTS: Compared with the nonheated group, overheated manipulation beyond 90℃ can significantly prolong the degradation properties for up to 3 to 4 weeks and enhance the mass stress of H-PRF membranes. A high-temperature treatment of 105℃ accompanied by the cell activity beneath H-PRF reduced more than half, and thus, the biological effect on human osteoblasts (hFOBs) also reduced dramatically. CONCLUSIONS: High thermal manipulation can prolong the degradation properties and enhance the mechanical properties of PRF membranes accompanied by the loss of biological effect.

The subcortical maternal complex protein Nlrp4f is involved in cytoplasmic lattice formation and organelle distribution.

In mammalian oocytes and embryos, the subcortical maternal complex (SCMC) and cytoplasmic lattices (CPLs) are two closely related structures. Their detailed compositions and functions remain largely unclear. Here, we characterize Nlrp4f as a novel component associated with the SCMC and CPLs. Disruption of maternal Nlrp4f leads to decreased fecundity and delayed preimplantation development in the mouse. Lack of Nlrp4f affects organelle distribution in mouse oocytes and early embryos. Depletion of Nlrp4f disrupts CPL formation but does not affect the interactions of other SCMC proteins. Interestingly, the loss of Khdc3 or Tle6, two other SCMC proteins, also disrupts CPL formation in mouse oocytes. Thus, the absence of CPLs and aberrant distribution of organelles in the oocytes caused by disruption of the examined SCMC genes, including previously reported Zbed3, Nlrp5, Ooep and Padi6, indicate that the SCMC is required for CPL formation and organelle distribution. Consistent with the role of the SCMC in CPL formation, the SCMC forms before CPLs during mouse oogenesis. Together, our results suggest that the SCMC protein Nlrp4f is involved in CPL formation and organelle distribution in mouse oocytes.

Impact of preanalytical freezing delay time on the stability of metabolites in oral squamous cell carcinoma tissue samples.

INTRODUCTION: Metabolite stability is critical for tissue metabolomics. However, changes in metabolites in tissues over time from the operating room to the laboratory remain underexplored. OBJECTIVES: In this study, we evaluated the effect of postoperative freezing delay time on the stability of metabolites in normal and oral squamous cell carcinoma (OSCC) tissues. METHODS: Tumor and paired normal tissues from five OSCC patients were collected after surgical resection, and samples was sequentially quenched in liquid nitrogen at 30, 40, 50, 60, 70, 80, 90 and 120 min (80 samples). Untargeted metabolic analysis by liquid chromatography-mass spectrometry/mass spectrometry in positive and negative ion modes was used to identify metabolic changes associated with delayed freezing time. The trends of metabolite changes at 30-120 and 30-60 min of delayed freezing were analyzed. RESULTS: 190 metabolites in 36 chemical classes were detected. After delayed freezing for 120 min, approximately 20% of the metabolites changed significantly in normal and tumor tissues, and differences in the metabolites were found in normal and tumor tissues. After a delay of 60 min, 29 metabolites had changed significantly in normal tissues, and 84 metabolites had changed significantly in tumor tissues. In addition, we constructed three tissue freezing schemes based on the observed variation trends in the metabolites. CONCLUSION: Delayed freezing of tissue samples has a certain impact on the stability of metabolites. For metabolites with significant changes, we suggest that the freezing time of tissues be reasonably selected according to the freezing schemes and the actual clinical situation.

Optimising fluid requirements after initial resuscitation: A pilot study evaluating mini-fluid challenge and passive leg raising test in patients with predicted severe acute pancreatitis.

BACKGROUND: The goals and approaches to fluid therapy vary through different stages of resuscitation. This pilot study was designed to test the safety and feasibility of a fluid therapy protocol for the second or optimisation stage of resuscitation in patients with predicted severe acute pancreatitis (SAP). METHODS: Spontaneously breathing patients with predicted SAP were admitted after initial resuscitation and studied over a 24-h period in a tertiary hospital ward. Objective clinical assessment (OCA; heart rate, mean arterial pressure, urine output, and haematocrit) was done at 0, 4, 8, 12, 18-20, and 24 h. All patients had mini-fluid challenge (MFC; 250 ml intravenous normal saline within 10 min) at 0 h and repeated at 4 and 8 h if OCA score ≥2. Patients who were fluid responsive (>10% change in stroke volume after MFC) received 5-10 ml/kg/h, otherwise 1-3 ml/kg/h until the next time point. Passive leg raising test (PLRT) was done at each time point and compared with OCA for assessing volume status and predicting fluid responsiveness. RESULTS: This fluid therapy protocol based on OCA, MFC, and PLRT and designed for the second stage of resuscitation was safe and feasible in spontaneously breathing predicted SAP patients. The PLRT was superior to OCA (at 0 and 8 h) for predicting fluid responsiveness and guiding fluid therapy. CONCLUSIONS: This pilot study found that a protocol for intravenous fluid therapy specifically for the second stage of resuscitation in patients with predicted SAP was safe, feasible, and warrants further investigation.