Multilevel transcrustal magmatic system beneath the Geysers-Clear Lake area.

Magmatism in the Quaternary Clear Lake volcanic field (CLVF), with its youngest eruption having only occurred c. 10 ka ago, is commonly invoked as the heat source for the world's largest commercial geothermal reservoir, The Geysers, in northern California. A shallow silicic magma reservoir in the upper-middle crust has been discovered for some time, but the location and mechanism of a potential deep mafic magma reservoir have remained elusive. Here, we present a seismic tomographic model that images the entire crustal column, clearly revealing a multilevel transcrustal magmatic system beneath the Geysers-Clear Lake area. Upwelling melts from the mantle traverse across the crust-mantle boundary and accumulate in the lower crust underneath the southeastern part of Clear Lake, resulting in a hot Moho in between. Mafic melts primarily ascend westward due to the extensional regime in the west and physical barrier effect from the overlying rigid ophiolite fragment, ultimately forming a shallow silicic magma reservoir underlying and heating The Geysers geothermal field. In addition, this study also links compositionally diverse volcanism in a continental setting to differentiation in a multilevel transcrustal magmatic system.

Staphylococcus aureus Enterotoxin B Is a Cofactor of Food Allergy beyond a Superantigen.

Staphylococcus aureus enterotoxin B (SEB), one of the most common bacterial toxins in food contamination, has been poorly understood in relationship to food allergy outcomes. To investigate whether the ingestion of enterotoxins in food allergens could affect the development of food allergy, OVA-sensitized female BALB/c mice were challenged with OVA added with different doses of SEB or LPS. Allergic symptoms, such as diarrhea rate and hypothermia, could be aggravated in mice challenged with OVA and a low dose of SEB. The increased differentiation of Th2 and reduced expression of CD103 in dendritic cells was found in mice coexposed to SEB and OVA. Additionally, there was an increasing differentiation of Th1 induced by a high dose of SEB. The expression of ST2+ in intestinal mast cells was also increased in mice sensitized with a low dose of SEB and OVA. Employing several in vitro cell culture models showed that the secretion of IL-33 from intestinal epithelial cells and IL-4 from group 2 innate lymphoid cells, activation of bone marrow-derived dendritic cells, and differentiation of naive T cells were induced by SEB and OVA. Our work proved that challenge with low-dose SEB and OVA partly aggravated the food allergy, suggesting a (to our knowledge) new finding of the potential cofactor of food allergy and that the contamination of SEB in food allergens deserves attention for allergic and normal individuals.

CCDC66 mutations are associated with high myopia through affected cell mitosis.

BACKGROUND: High myopia (HM) refers to an eye refractive error exceeding -5.00 D, significantly elevating blindness risk. The underlying mechanism of HM remains elusive. Given the extensive genetic heterogeneity and vast genetic base opacity, it is imperative to identify more causative genes and explore their pathogenic roles in HM. METHODS: We employed exome sequencing to pinpoint the causal gene in an HM family. Sanger sequencing was used to confirm and analyse the gene mutations in this family and 200 sporadic HM cases. Single-cell RNA sequencing was conducted to evaluate the gene's expression patterns in developing human and mouse retinas. The CRISPR/Cas9 system facilitated the gene knockout cells, aiding in the exploration of the gene's function and its mutations. Immunofluorescent staining and immunoblot techniques were applied to monitor the functional shifts of the gene mutations at the cellular level. RESULTS: A suspected nonsense mutation (c.C172T, p.Q58X) in CCDC66 was found to be co-segregated with the HM phenotype in the family. Additionally, six other rare variants were identified among the 200 sporadic patients. CCDC66 was consistently expressed in the embryonic retinas of both humans and mice. Notably, in CCDC66-deficient HEK293 cells, there was a decline in cell proliferation, microtube polymerisation rate and ace-tubulin level. Furthermore, the mutated CCDC66 failed to synchronise with the tubulin system during Hela cell mitosis, unlike its wild type counterpart. CONCLUSIONS: Our research indicates that the CCDC66 variant c.C172T is associated with HM. A deficiency in CCDC66 might disrupt cell proliferation by influencing the mitotic process during retinal growth, leading to HM.

GLRA2 gene mutations cause high myopia in humans and mice.

BACKGROUND: High myopia (HM) is a leading cause of blindness that has a strong genetic predisposition. However, its genetic and pathogenic mechanisms remain largely unknown. Thus, this study aims to determine the genetic profile of individuals from two large Chinese families with HM and 200 patients with familial/sporadic HM. We also explored the pathogenic mechanism of HM using HEK293 cells and a mouse model. METHODS: The participants underwent genome-wide linkage analysis and exome sequencing. Visual acuity, electroretinogram response, refractive error, optical parameters and retinal rod cell genesis were measured in knockout mice. Immunofluorescent staining, biotin-labelled membrane protein isolation and electrophysiological characterisation were conducted in cells transfected with overexpression plasmids. RESULTS: A novel HM locus on Xp22.2-p11.4 was identified. Variant c.539C>T (p.Pro180Leu) in GLRA2 gene was co-segregated with HM in the two families. Another variant, c.458G>A (p.Arg153Gln), was identified in a sporadic sample. The Glra2 knockout mice showed myopia-related phenotypes, decreased electroretinogram responses and impaired retinal rod cell genesis. Variants c.458G>A and c.539C>T altered the localisation of GlyRα2 on the cell membrane and decreased agonist sensitivity. CONCLUSION: GLRA2 was identified as a novel HM-causing gene. Its variants would cause HM through altered visual experience by impairing photoperception and visual transmission.

Effects of medicine food homologous materials on food allergy-associated factors: intestinal oxidative stress, intestinal inflammation and Th2 immune response.

BACKGROUND: Food allergies could be regulated via Th1/Th2 balance, intestinal oxidative stress and inflammation, which were considered as food allergy-associated factors. Medicine-food homologous materials (MFHM) were considered as a significant factor with respect to preventing human diseases. To evaluate the associations between MFHM and food allergy-associated factors, two types of MFHM with the remarkable function of anti-oxidation and anti-inflammation, Gardeniae fructus (Gar) and Sophorae glos (Sop), were chosen. RESULTS: By constructing an H2O2-induced oxidative stress model of Caco-2 cells and an intestinal inflammatory cell model of Caco-2 cells with tumor necrosis factor-α and interleukin (IL)-13, the contents of anti-oxidative enzymes (SOD and GSH), inflammatory factor (IL-8) and tight junction proteins (zonula occludens-1, occludin and claudin-1) in Caco-2 cells were determined. Moreover, the anti-allergic effects of digestive Sop and Gar were evaluated by measuring the levels of Th1/Th2/Treg cytokines in the spleen cells of sensitized mice. The results showed that the SOD and GSH were obviously increased and the gene and protein expression of IL-8 and claudin-1 were improved with the incubation of digested Sop. Th2 cytokine was reduced and Th1/Th2 balance was promoted on coincubation with ovalbumin (OVA) and digested Sop in the splenocytes. However, the digested Gar had no effect. CONCLUSION: The digested Sop not only had suppressive effects on intestinal oxidative stress and inflammation, but also had regulative effects on Th1/Th2 balance. This finding demonstrated that not all of the MFHM with anti-oxidant and anti-inflammatory effects have anti-allergic activities. The present study may be contributing toward establishing a screening model to identify the anti-allergic MFHM. © 2024 Society of Chemical Industry.

Shedding light on the interaction of ovalbumin and resveratrol: structure, digestibility, transport, and allergenicity assessment of OVA-RES complexes.

BACKGROUND: The interaction between food allergens and plant polyphenols has become a safe and effective management strategy to prevent food allergies. Ovalbumin (OVA) is the most abundant allergen in egg whites. Resveratrol (RES) is a plant polyphenol that is abundant in red grapes, berries, and peanuts, and has an anti-allergic effect on allergy-related immune cells. However, there is little information about the effect of RES on the allergenicity of OVA. In this study, the effect of RES on the allergenicity of OVA was investigated. RESULTS: Molecular docking and spectroscopic studies indicated that the addition of RES changed the structure of OVA. The digestion and transfer rate of OVA-RES were effectively improved with an in vitro gastrointestinal digestion model and Caco-2 cell model, especially when the molar ratio of OVA-RES was 1:20. Meanwhile, the KU812 cell degranulation assay proved that the potential allergenicity was remarkably decreased while the molar ratios of OVA-RES were increased to 1:20. Furthermore, hydrogen bonds and van der Waals forces were the dominating forces to stabilize the OVA-RES complexes. CONCLUSION: All the findings demonstrated that the potential allergenicity of OVA was reduced when interacting with RES, and RES can be a potential food material for preparing a hypoallergenic protein, especially for egg allergy. © 2023 Society of Chemical Industry.

The potential of orally exposed risk factors and constituents aggravating food allergy: Possible mechanism and target cells.

Food allergy is a significant concern for the health of humans worldwide. In addition to dietary exposure of food allergens, genetic and environmental factors also play an important role in the development of food allergy. However, only the tip of the iceberg of risk factors in food allergy has been identified. The importance of food allergy caused by orally exposed risk factors and constituents, including veterinary drugs, pesticides, processed foods/derivatives, nanoparticles, microplastics, pathogens, toxins, food additives, dietary intake of salt/sugar/total fat, vitamin D, and therapeutic drugs, are highlighted and discussed in this review. Moreover, the epithelial barrier hypothesis, which is closely associated with the occurrence of food allergy, is also introduced. Additionally, several orally exposed risk factors and constituents that have been reported to disrupt the epithelial barrier are elucidated. Finally, the possible mechanisms and key immune cells of orally exposed risk factors and constituents in aggravating food allergy are overviewed. Further work should be conducted to define the specific mechanism by which these risk factors and constituents are driving food allergy, which will be of central importance to the targeted therapy of food allergy.

Quantifying allergenic proteins using antibody-based methods or liquid chromatography-mass spectrometry/mass spectrometry: A review about the influence of food matrix, extraction, and sample preparation.

Accurate quantification of allergens in food is crucial for ensuring consumer safety. Pretreatment steps directly affect accuracy and efficiency of allergen quantification. We systematically reviewed the latest advances in pretreatment steps for antibody-based methods and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) protein quantification methods in food. For antibody-based methods, the effects induced by food matrix like decreased allergen solubility, epitope masking, and nonspecific binding are of the upmost importance. To mitigate interference from the matrix, effective and proper extraction can be used to obtain the target allergens with a high protein concentration and necessary epitope exposure. Removal of interfering substances, extraction systems (buffers and additives), assistive technologies, and commercial kits were discussed. About LC-MS/MS quantification, the preparation of the target peptides is the crucial step that significantly affects the efficiency and results obtained from the MS detector. The advantages and limitations of each method for pre-purification, enzymatic digestion, and peptide desalting were compared. Additionally, the application characteristics of microfluidic-based pretreatment devices were illustrated to improve the convenience and efficiency of quantification. A promising research direction is the targeted development of pretreatment methods for complex food matrices, such as lipid-based and carbohydrate-based matrices.

Active polysaccharides: a new roadmap for the prevention and treatment of food allergy.

Active polysaccharides are extensively utilized in the fields of food and medicine because of their rich functional properties and structural plasticity. However, there are still few systematic studies and reviews on active polysaccharides for allergy. Allergy, especially food allergy, occurs frequently around the world and is related to a variety of factors such as age, genetics and dietary habits. Currently in medicine, avoiding allergens and desensitizing can effectively relieve allergy symptoms, but these are difficult to maintain over the long term and come with risks. Based on the supplementation of dietary nutrition to these two treatments, it has been discovered in recent years that the use of active ingredients from natural substances can effectively intervene in allergies. Considering the potential of active polysaccharides in this regard, we systematically characterize the latent patterns of polysaccharides in allergic symptoms and pathogenesis, including the aspects of gut, immunomodulatory, oxidative stress and signaling pathways, as well as the application prospect of them in allergy. It can be found that active polysaccharides have excellent anti-allergic potential, especially from the ocean. We believe that the active polysaccharides are associated with the treatment of allergic diseases, which may provide the benefits to allergy sufferers in the future.

Facile synthesis of spherical covalent organic frameworks for enrichment and quantification of aryl organophosphate esters in mouse serum and tissues.

Here, an imine-linked-based spherical covalent organic framework (COF) was prepared at room temperature. The as-synthesized spherical COF served as an adsorbent in dispersive solid-phase extraction (dSPE), by its virtue of great surface area (1542.68 m2 /g), regular distribution of pore size (2.95 nm), and excellent stability. Therefore, a simple and high-efficiency dispersive solid phase extraction method based on a spherical COF coupled with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was established to determine aryl organophosphate esters in biological samples. This approach displayed favorable linearity in the range of 10.0-1000.0 ng/L (r > 0.9989), a high signal enhancement factor (58.8-181.8 folds) with low limits of detection (0.3-3.3 ng/L). Moreover, it could effectively eliminate complex matrix interference to accurately extract seven aryl organophosphate esters from mouse serum and tissue samples with spiked recoveries of 82.0%-117.4%. The as-synthesized spherical COF has been successfully applied in sample preparation. The dSPE-HPLC-MS/MS method based on a spherical COF has potential application to study the pollutants' metabolism in vivo.

Hybrid RCA-DLS assay combined with aPCR for sensitive Salmonella enteritidis detection.

Salmonella infection could come from eating contaminated meat or raw eggs, and drinking milk or water contaminated by Salmonella enteritidis. Therefore, it is necessary to explore a fast and easy method for the detection of S. enteritidis in these diverse samples. For this purpose, a novel particle size sensing tool was designed for ultrasensitive and accurate S. enteritidis detection. This assay consisted of rolling circle amplification (RCA) with dynamic light scattering (DLS) using gold nanoparticles (AuNPs) modified with DNA probe as DNA-AuNPs as the capture surface into a hybrid RCA-DLS assay combined with asymmetric polymerase chain reaction (aPCR) and subsequent detection. Under optimal experimental conditions, the novel hybrid RCA-DLS assay combined with aPCR for S. enteritidis reached a limit of detection (LOD) as low as 3 × 100 CFU/mL in pure culture. In spiked milk samples, the LOD was 2.0 × 100 CFU/mL without pre-enriched bacteria. The total time of RCA-DLS assay was about 6 h which including genomic DNA extraction, aPCR, RCA and DLS determination. The hybrid RCA-DLS assay combined with aPCR holds promise in the specific and sensitive S. enteritidis detection.

Regional cerebral blood flow in major depression treated with electroconvulsive therapy: an arterial spin labeling magnetic resonance study.

Until recently, regional cerebral blood flow (rCBF) in major depressive disorder (MDD) patients treated with electroconvulsive therapy (ECT) using arterial spin labeling (ASL) magnetic resonance imaging (MRI) have seldom been studied. We report here 10 patients with MDD treated by bilateral frontotemporal ECT. rCBF was assessed with ASL MRI pre- and post-ECT, and compared with patients treated by antidepressants. Compared to pre-ECT, rCBF significantly decreased in the bilateral frontal gyrus. Compared to medication, in patients treated with ECT, rCBF showed a significant decrease in the left amygdala, parahippocampal and olfactory gyrus, and right occipital, lingual, calcarine gyrus, and significantly increased in the bilateral frontal gyrus and right frontal gyrus. Compared with antidepressants, ECT altered rCBF, and showed potential to be a superior treatment for major depressive disorder.

Pasteurization induced protein interaction decreased the potential allergenicity of ovalbumin and ovomucoid in egg white.

BACKGROUND: Approximately 9.9% of young children in China suffer from egg allergies. Ovalbumin (OVA) and ovomucoid (OVM) are both the main allergens with higher allergenicity in egg white. The previous studies mainly focused on the effects of pasteurization on the structure and allergenicity of the isolated protein itself. The effects of the interaction between OVA and OVM on their spatial structure and allergenicity under pasteurization are still unclear. Therefore, in this study, the spectroscopic, immunological, and cytological methods were used to investigate the effects on OVA and OVM by their interactions which were induced by the following pasteurization, heating for 10 min at 60, 65, and 70 °C, respectively. RESULTS: Results indicated that OVA and OVM could form macromolecular aggregates by their interaction at 70 °C, and their solubility was decreased while turbidity was increased. The spatial structures of OVA and OVM were both changed by their interaction, when pasteurization temperature was at 70 °C the exposure of their hydrophobic groups and α-helix content were decreased while their ß-sheet was increased. The potential allergenicity of OVA and OVM was also changed, which showed that the immunoglobulin G (IgG)-binding ability of OVA and OVM could be increased, and their IgE-binding ability was decreased a bit. The releases of interleukin 4 (IL-4), IL-6, ß-HEX, histamine and tumor necrosis factor alpha (TNF-α) from OVA-OVM-induced KU812 cells were all decreased at 70 °C. CONCLUSION: Therefore, according to the results, if the liquid egg products were pasteurized for 10 min, the temperature of 70 °C should be carefully considered. © 2022 Society of Chemical Industry.

[Metabolomic changes of neonatal sepsis: an exploratory clinical study]. / æ–°ç”Ÿå„¿è´¥è¡€ç—‡çš„ä»£è°¢ç»„å­¦æ”¹å˜ï¼šä¸€é¡¹æŽ¢ç´¢æ€§ä¸´åºŠç ”ç©¶.

OBJECTIVES: To study the metabolic mechanism of neonatal sepsis at different stages by analyzing the metabolic pathways involving the serum metabolites with significant differences in neonates with sepsis at different time points after admission. METHODS: A total of 20 neonates with sepsis who were hospitalized in the Department of Neonatology, Hunan Provincial People's Hospital, from January 1, 2019 to January 1, 2020 were enrolled as the sepsis group. Venous blood samples were collected on days 1, 4, and 7 after admission. Ten healthy neonates who underwent physical examination during the same period were enrolled as the control group. Ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry was used for the metabonomic analysis of serum samples to investigate the change in metabolomics in neonates with sepsis at different time points. RESULTS: On day 1 after admission, the differentially expressed serum metabolites between the sepsis and control groups were mainly involved in the biosynthesis of terpenoid skeleton. For the sepsis group, the differentially expressed serum metabolites between days 1 and 4 after admission were mainly involved in pyruvate metabolism, and those between days 4 and 7 after admission were mainly involved in the metabolism of cysteine and methionine. The differentially expressed serum metabolites between days 1 and 7 after admission were mainly involved in ascorbic acid metabolism. CONCLUSIONS: The metabolic mechanism of serum metabolites varies at different stages in neonates with sepsis and is mainly associated with terpenoid skeleton biosynthesis, pyruvate metabolism, cysteine/methionine metabolism, and ascorbic acid metabolism.

Clinical traits of patients with major depressive disorder with comorbid borderline personality disorder based on propensity score matching.

BACKGROUND: Major depressive disorder (MDD) with comorbid borderline personality disorder (BPD) makes the clinical symptoms of patients more complex and more difficult to treat, so more attention should be paid to the recognition of their clinical features. This study investigated the differences between patients with MDD with and without BPD in clinical traits. METHODS: Propensity score matching was used to analyze the retrospective patients' data from August 2012 to September 2019. Altogether, 1381 patients with MDD were enrolled; 38 patients with MDD were matched to compare demographic data, and scores on the Hamilton Depression Scale, Hamilton Anxiety Scale (HAMA), Self-Rating Depression Scale (SDS), Modified Overt Aggression Scale (MOAS), and the frequency of nonsuicidal self-harm (NSSH). RESULTS: Compared to patients with MDD without BPD, the age of onset of patients with MDD with comorbid BPD was significantly earlier (t = 3.25, p = .00). The scores of HAMA (t = -2.28, p = .03), SDS (t = 9.31, p = .00), MOAS (t = -13.67, p = .00), verbal aggression (t = -3.79, p = .00), aggression against objects (t = -2.84, p = .00), aggression against others (t = -6.70, p = .00), and aggression against self (t = -9.22, p = .00) were significantly higher in patients with MDD with comorbid BPD. Moreover, the frequency of NHSS in these patients was significantly higher (χ2 = 20.13, p = .00). MOAS was an independent influencing factor in these (odds ratio = 7.38, p = .00). CONCLUSIONS: Patients with BPD showed early onset and increased complaints relative to symptoms, accompanied by obvious anxiety symptoms, impulsive behavior, and NSSH. Therefore, patients with MDD with impulsive behavior have comorbid BPD.

A fish scale-like magnetic nanomaterial as a highly efficient sorbent for monitoring the changes in auxin levels under cadmium stress.

Sorbents with high surface utilization and good dispersibility are of great importance for the extraction performance of magnetic solid-phase extraction (MSPE). In this study, a fish scale-like magnetic nanomaterial (Co@Co3O4/OCN) was synthesized, which can be used as a highly efficient MSPE sorbent due to its strong magnetism, special morphology, doping of N element, numerous micro-mesopore cavities and organic functional groups (hydroxyl and carboxyl). Furthermore, a Co@Co3O4/OCN-based MSPE method for monitoring the changes in the levels of three auxins (indole-3-acetic acid, indole-3-propionic acid and 3-indole butyric acid) was successfully established. Wide linear ranges (1.0-1000.0 pg mL-1) with good correlation coefficients (R > 0.9992), low limits of detection (LODs, 0.2-4.0 pg mL-1) and satisfactory repeatability (RSD ≤5.9%, n = 3) were obtained. Using the developed method, various growth parts and different growth periods of plants under Cd stress were monitored. The results showed that auxins in various parts of plants showed differential response under Cd stress, and there was a threshold for the changes in auxin levels against Cd stress. This indicates that the developed fish scale-like Co@Co3O4/OCN nanomaterial has a good application prospect for enriching small molecular targets containing hydroxyl and carboxyl groups.

Polyphenol-oxidase-catalyzed cross-linking of Ara h 2: reaction sites and effect on structure and allergenicity.

BACKGROUND: Peanut is among the most common of food allergies, and one of its allergens is Ara h 2. A previous study revealed that this allergen was recognized by serum immunoglobulin E (IgE) in over 90% of a peanut-allergic patient population. Enzymatic cross-linking is a popular processing method used to tailor food functionality, such as antigenicity. RESULT: The cross-linking reactions of Ara h 2 were catalyzed by polyphenol oxidase (PPO), and the relevant reaction sites were identified using mass spectrometry and StavroX software. Two pairs of intramolecular cross-linking peptides and two intermolecular cross-linking peptides were found. Intramolecular cross-linking was speculated to occur between ARG131 (amino acids 116-131) and TYR65 (amino acids 63-80) and between TYR60 (amino acids 56-62) and ARG92 (amino acids 92-102); the intermolecular cross-linking sites were ARG31 with TYR84 or TYR89 and TYR65 or TYR72 with ARG92 or ARG102 . Three out of four cross-linking peptides were found in α-helices, and destruction of this secondary structure resulted in a loose tertiary structure. Although seven linear allergen epitopes were involved in cross-linking, the IgE binding capacity of protein changed slightly, while its sensitization potential decreased in mouse model. CONCLUSION: Exploring the structural change of Ara h 2 after cross-linking is beneficial in further understanding the influence of structure on sensitization. This result indicated the future possibility of precision processing on structure of proteins to improve their properties. © 2019 Society of Chemical Industry.

Astragalus polysaccharides suppresses high glucose-induced metabolic memory in retinal pigment epithelial cells through inhibiting mitochondrial dysfunction-induced apoptosis by regulating miR-195.

BACKGROUND: Metabolic memory contributes to the development of diabetic retinopathy (DR), which is the complication of diabetes. But it's still unknown how to prevent the metabolic memory to treat the DR. In our study, we want to examine the function of Astragalus polysaccharides (APS) in the metabolic memory of retinal pigment epithelium (RPE) pretreated with high glucose (HG). METHODS: ARPE-19 and PRPE cells were exposed to HG followed by normal glucose (NG) treatment with or without APS. QPCR was used to examine the levels of miR-195 and Bcl-2. MDA and SOD detection assays were used to examine the oxidative stress level. Western blotting and immunostaining were applied to detect the protein level of mitochondrial damage and apoptotic signaling pathway. Flow cytometry and TUNEL staining were used to analyze cell apoptosis. Luciferase assay was used to examine the direct target of miR-195. RESULTS: APS treatment significantly decreased the expression of miR-195, while increased the expression of Bcl-2 with optimized dosages which were induced by HG treatment, even after replacing the HG with NG. And we found Bcl-2 was the direct target of miR-195. APS alleviated the oxidative stress, mitochondrial damage and cell apoptosis induced by HG and HG + NG treatments in RPE cells via regulating miR-195. Furthermore, we found overexpression of miR-195 abolished the alleviated effects of APS on the HG-treated RPE cells. CONCLUSIONS: APS suppressed high glucose-induced metabolic memory in retinal pigment epithelial cells through inhibiting mitochondrial dysfunction-induced apoptosis by regulating miR-195.

LncRNA-MEG3 alleviates high glucose induced inflammation and apoptosis of retina epithelial cells via regulating miR-34a/SIRT1 axis.

BACKGROUND: Diabetic retinopathy (DR) is the serious complication of diabetes, which could lead to blindness. Inflammation and apoptosis are hallmark of DR, but mechanism of their regulation is little known. LncRNA-MEG3 is associated with multiple biological processes including proliferation, apoptosis and inflammation response, and is dramatically decreased in DR. However, the role and underlying mechanism of MEG3 in DR is unclear. This study is aimed to reveal the signaling mechanisms of MEG3 in inflammation and apoptosis of DR. METHODS: ARPE-19 cells were applied for this research. MEG3 was cloned into pcDNA3.1. miR-34a was overexpressed and inhibited by transfecting with mimics and inhibitor, respectively. The expression level was detected by qRT-PCR and western blotting. The targeted regulatory relationship was analyzed by dual luciferase assay. Cytokine secretion, cell viability and apoptosis were detected by ELISA assay, MTT assay and flow cytometry analysis, respectively. RESULTS: High glucose (HG) inhibited MEG3 and SIRT1 expression and enhanced miR-34a expression. MEG3 could promote SIRT1 expression by targeting miR-34a. MEG3 overexpression and miR-34a knockdown could inhibit HG-induced apoptosis and secretion of inflammation cytokines including IL-1ß, IL-6 and TNF-α, but miR-34a overexpression alleviated such effects of MEG3. Furthermore, MEG3 overexpression also inhibited NF-κB signaling pathway and increased Bcl-2/Bax ratio via down-regulating miR-34a. CONCLUSION: MEG3 could alleviate HG-inducing apoptosis and inflammation via inhibiting NF-κB signaling pathway by targeting miR-34a/SIRT1 axis. This finding illustrated the function and mechanism of MEG3 in DR, and MEG3 might serve as potential therapeutic target for DR.

Photoelectrochemical immunoassay of aflatoxin B1 in foodstuff based on amorphous TiO2 and CsPbBr3 perovskite nanocrystals.

Aflatoxin B1 (AFB1) pollution is one of the most serious problems for food safety. In this paper, a split-type photoelectrochemical (PEC) immunoassay was designed for sensitive detection of AFB1 in foodstuffs by using amorphous TiO2 with all-inorganic perovskite CsPbBr3 nanocrystals (CsPbBr3/a-TiO2). The a-TiO2 layer not only improved the stability of CsPbBr3 nanocrystals, but also facilitated charge transfer, which resulted in the increasing photocurrent of the nanocomposites. Initially, a competitive-type enzyme immunoreaction was executed on a high-binding microplate between the analyte and alkaline phosphatase (ALP)-labeled AFB1-bovine serum albumin (AFB1-BSA) conjugate. Accompanied by the formation of the immunocomplex, the carried ALP triggered enzymatic hydrolysis to generate ascorbic acid (AA, as an electron donor) for increasing the photocurrent of the CsPbBr3/a-TiO2-modified electrode. Coupling with the competitive enzyme immunoassay, the photocurrent of the modified electrode decreased with the increase of target AFB1 concentration in a dynamic working range from 0.01 ng mL-1 to 15 ng mL-1 with a limit of detection (LOD) of 2.8 pg mL-1 under optimum conditions. Furthermore, the photoelectrochemical immunoassay was also utilized to detect AFB1 in peanut and corn samples, giving acceptable accuracy in comparison with the referenced AFB1 enzyme-linked immunosorbent assay (ELISA) method.