[Comparison of the effects of using iRoot BP plus and MTA apical barrier surgery in young permanent teeth with chronic apical periodontitis].

PURPOSE: To explore the effect of using iRoot BP plus and MTA apical barrier surgery in young permanent teeth with chronic apical periodontitis. METHODS: A total of 122 patients with chronic periapical periodontitis with open root tips of permanent teeth were randomly divided into experimental group (n=61, 61 teeth) and a control group (n=61, 61 teeth). Patients in the experimental group received iRoot BP plus plus apical barrier surgery, while those in the control group received MTA apical barrier surgery. The old periapical index (O-PAI), apical transmission area, efficacy, treatment times, and inflammatory factor levels of the two groups of patients were compared at 3, 6, 9, and 12 months after surgery. SPSS 19.0 software package was used for statistical analysis. RESULTS: At 12 months after surgery, the O-PAI ratings of the experimental group and the control group were (1.48±0.36) and (1.71±0.42), respectively, and the apical transmission area was (0.51±0.14) and (1.09±0.31). There was a significant difference in the O-PAI ratings and apical transmission area between the two groups(P＜0.05). At 3 months, 6 months, and 12 months after surgery, the O-PAI scores of patients in both groups gradually decreased (P＜0.05). After 12 months of treatment, the success rates of the experimental group and the control group were 98.36% and 88.52%, respectively, with significant difference between the two groups (P＜0.05). The treatment frequency of patients in the experimental group and the control group was (3.64±0.58) times and (4.72±0.61) times, respectively, with a significant difference between the two groups(P＜0.05). After 3 months of treatment, the serum hs-CRP levels in the experimental group and the control group were (6.89±1.13) mg/L and (7.25±1.40) mg/L, respectively, with a significant difference compared to pre-treatment(P＜0.05). After 3 months of treatment, the serum IL-6 levels in the experimental group and the control group were (82.04±19.62) mg/L and (87.52±20.85) mg/L, respectively, with significant differences compared to pre-treatment (P＜0.05). There was no significant difference in serum IL-6 and hs-CRP levels between the two groups before and after treatment(P＞0.05). CONCLUSIONS: iRoot BP plus apical barrier surgery for the treatment of chronic apical periodontitis with open permanent teeth can reduce the O-PAI index, decrease the number of postoperative visits, and have a higher postoperative success rate.

In vitro antibacterial activity of danofloxacin against Escherichia coli isolated from pigeons and its pharmacokinetic in pigeons.

This experiment aimed to investigate the in vitro antimicrobial activity of danofloxacin against Escherichia coli (E. coli) isolated from pigeons, as well as the pharmacokinetics of danofloxacin in pigeons following oral (PO), intramuscular (IM), and intravenous (IV) administration. The minimum inhibitory concentration (MIC) of danofloxacin was first determined for 38 clinical E. coli strains using the micro broth dilution method. Subsequently, 30 healthy pigeons were weighed and randomly divided into 3 groups: IM, IV, and PO, with 10 pigeons in each group. Danofloxacin was given at 5 mg/kg body weight (BW) through 3 different routes. Blood was collected, and plasma was separated at various time points from 0 to 48 h. Plasma samples were analyzed for danofloxacin concentrations using a validated HPLC method. Pharmacokinetic analysis was performed using Phoenix software and a noncompartmental analytical (NCA) method. The results indicated that danofloxacin had a strong antibacterial effect on E. coli, with a MIC50 of 0.5 µg/mL. The noncompartmental analysis showed that after PO and IM administration at 5 mg/kg in pigeons, peak plasma concentrations (Cmax) of 0.61 and 1.62 µg/mL were reached at 4.5 and 0.53 h, respectively. The oral and intramuscular bioavailability (F) were 68.08% ± 24.82% and 87.82% ± 25.36%, respectively. Following IV administration, danofloxacin was widely distributed in pigeons, with volume of distribution (VZ) and volume of distribution at steady state (VSS) values of 6.11 ± 2.01 and 4.65 ± 1.62 L/kg, respectively, and was eliminated slowly, with an elimination half-life (t1/2λz) of 6.41 ± 2.15 h. Based on the calculated ratio values of AUC/MIC, the current IV, IM, and PO doses of 5 mg/kg of danofloxacin would be expected to effectively treat pigeons infected with E. coli strains with MIC values equal to or less than 0.5 µg/mL.

Targeting Lactobacillus johnsonii to reverse chronic kidney disease.

Accumulated evidence suggested that gut microbial dysbiosis interplayed with progressive chronic kidney disease (CKD). However, no available therapy is effective in suppressing progressive CKD. Here, using microbiomics in 480 participants including healthy controls and patients with stage 1-5 CKD, we identified an elongation taxonomic chain Bacilli-Lactobacillales-Lactobacillaceae-Lactobacillus-Lactobacillus johnsonii correlated with patients with CKD progression, whose abundance strongly correlated with clinical kidney markers. L. johnsonii abundance reduced with progressive CKD in rats with adenine-induced CKD. L. johnsonii supplementation ameliorated kidney lesion. Serum indole-3-aldehyde (IAld), whose level strongly negatively correlated with creatinine level in CKD rats, decreased in serum of rats induced using unilateral ureteral obstruction (UUO) and 5/6 nephrectomy (NX) as well as late CKD patients. Treatment with IAld dampened kidney lesion through suppressing aryl hydrocarbon receptor (AHR) signal in rats with CKD or UUO, and in cultured 1-hydroxypyrene-induced HK-2 cells. Renoprotective effect of IAld was partially diminished in AHR deficiency mice and HK-2 cells. Our further data showed that treatment with L. johnsonii attenuated kidney lesion by suppressing AHR signal via increasing serum IAld level. Taken together, targeting L. johnsonii might reverse patients with CKD. This study provides a deeper understanding of how microbial-produced tryptophan metabolism affects host disease and discovers potential pathways for prophylactic and therapeutic treatments for CKD patients.

Causal association of juvenile idiopathic arthritis or JIA-associated uveitis and gut microbiota: a bidirectional two-sample Mendelian randomisation study.

Background: The gut microbiota significantly influences the onset and progression of juvenile idiopathic arthritis (JIA) and associated uveitis (JIAU); however, the causality remains unclear. This study aims to establish a causal link between gut microbiota and JIA or JIAU. Methods: Using publicly available genome-wide association studies (GAWS) summary data, we conducted a two-sample Mendelian randomisation (MR) analysis employing various methods, namely inverse variance weighted (IVW), simple mode, weighted mode, weighted median and MR-Egger regression methods, to assess the causal association between JIA or JIAU and gut microbiota. Sensitivity analyses, including Cochrane's Q test, MR-Egger intercept test, leave-one-out analysis and MR-PRESSO, were performed to evaluate the robustness of the MR results. Subsequently, reverse MR analysis was conducted to determine causality between gene-predicted gut microbiota abundance and JIA or JIAU. Results: The MR analysis revealed a causal association between gut microbiota abundance variations and JIA or JIAU risk. Specifically, the increased abundance of genus Ruminococcaceae UCG013 (OR: 0.055, 95%CI: 0.006-0.103, p = 0.026) and genus Ruminococcaceae UCG003 (ß: 0.06, 95%CI: 0.003-0.117, p = 0.041) correlated with an increased risk of JIA, while genus Lachnospiraceae UCG001 (OR: 0.833, 95%CI: 0.699~0.993, p = 0.042) was associated with a reduced risk of JIA, among others. Sensitivity analysis confirmed MR analysis robustness. Conclusions: This study provides substantial evidence supporting a causal association between genetically predicted gut microbiota and JIA or JIAU. It highlights the significant role of intestinal flora in JIA or JIAU development, suggesting their potential as novel biomarkers for diagnosis and prevention. These findings offer valuable insights to mitigate the impact of JIA or JIAU.

Regioselective Synthesis of α-Quaternary Amino Acid Derivatives Enabled by Photoinduced Energy Transfer.

α-Quaternary amino acids have found application in many biologically relevant compounds and pharmaceuticals. Although there are many methods for the synthesis of α-quaternary amino acids, most of them are mainly realized with the aid of transition metals and complex ligands. We present herein a 2,7-Br-4CzIPN catalyzed regioselective alkylation of azlactones with redox-active esters via radical-radical couplings. Strikingly, this approach is devoid of any metal or additive and shows broad scope and superior sensitive functional group compatibility.

Exploring the Anti-Inflammatory Effect of Tryptanthrin by Regulating TLR4/MyD88/ROS/NF-κB, JAK/STAT3, and Keap1/Nrf2 Signaling Pathways.

Tryptanthrin (TRYP) is the main active ingredient in Indigo Naturalis. Studies have shown that TRYP had excellent anti-inflammatory activity, but its specific mechanism has been unclear. In this work, the differentially expressed proteins resulting from TRYP intervention in LPS-stimulated RAW264.7 cells were obtained based on tandem mass tag proteomics technology. The anti-inflammatory mechanism of TRYP was further validated by a combination of experiments using the LPS-induced RAW264.7 cell model in vitro and the DSS-induced UC mouse model (free drinking 2.5% DSS) in vivo. The results demonstrated that TRYP could inhibit levels of NO, IL-6, and TNF-α in LPS-induced RAW264.7 cells. Twelve differential proteins were screened out. And the results indicated that TRYP could inhibit upregulated levels of gp91phox, p22phox, FcεRIγ, IKKα/ß, and p-IκBα and reduce ROS levels in vitro. Besides, after TRYP treatment, the health conditions of colitis mice were all improved. Furthermore, TRYP inhibited the activation of JAK/STAT3, nuclear translocation of NF-κB p65, and promoted the nuclear expression of Nrf2 in vitro and in vivo. This work preliminarily indicated that TRYP might suppress the TLR4/MyD88/ROS/NF-κB and JAK/STAT3 signaling pathways to exert anti-inflammatory effects. Additionally, TRYP could achieve antioxidant effects by regulating the Keap1/Nrf2 signaling pathway.

Exploring the Origins and Evolution of Oxygenic and Anoxygenic Photosynthesis in Deeply Branched Cyanobacteriota.

Cyanobacteriota, the sole prokaryotes capable of oxygenic photosynthesis (OxyP), occupy a unique and pivotal role in Earth's history. While the notion that OxyP may have originated from Cyanobacteriota is widely accepted, its early evolution remains elusive. Here, by using both metagenomics and metatranscriptomics, we explore 36 metagenome-assembled genomes from hot spring ecosystems, belonging to two deep-branching cyanobacterial orders: Thermostichales and Gloeomargaritales. Functional investigation reveals that Thermostichales encode the crucial thylakoid membrane biogenesis protein, vesicle-inducing protein in plastids 1 (Vipp1). Based on the phylogenetic results, we infer that the evolution of the thylakoid membrane predates the divergence of Thermostichales from other cyanobacterial groups and that Thermostichales may be the most ancient lineage known to date to have inherited this feature from their common ancestor. Apart from OxyP, both lineages are potentially capable of sulfide-driven AnoxyP by linking sulfide oxidation to the photosynthetic electron transport chain. Unexpectedly, this AnoxyP capacity appears to be an acquired feature, as the key gene sqr was horizontally transferred from later-evolved cyanobacterial lineages. The presence of two D1 protein variants in Thermostichales suggests the functional flexibility of photosystems, ensuring their survival in fluctuating redox environments. Furthermore, all MAGs feature streamlined phycobilisomes with a preference for capturing longer-wavelength light, implying a unique evolutionary trajectory. Collectively, these results reveal the photosynthetic flexibility in these early-diverging cyanobacterial lineages, shedding new light on the early evolution of Cyanobacteriota and their photosynthetic processes.

Thioproline-Based Oxidation Strategy for Direct Preparation of N-Terminal Thiazolidine-Containing Peptide Thioesters from Peptide Hydrazides.

We describe a simple and robust oxidation strategy for preparing N-terminal thiazolidine-containing peptide thioesters from peptide hydrazides. We find for the first time that l-thioproline can be used as a protective agent to prevent the nitrosation of N-terminal thiazolidine during peptide hydrazide oxidation. The thioproline-based oxidation strategy has been successfully applied to the chemical synthesis of CC chemokine ligand-2 (69aa) and omniligase-C (113aa), thereby demonstrating its utility in hydrazide-based native chemical ligation.

Association between serum vitamin D concentration and liver fibrosis in diabetes mellitus patients: a cross-sectional study from the NHANES database.

AIM: Liver fibrosis (LF) is a common complication of diabetes mellitus (DM). Studies have found that vitamin D (VD), as a modifiable factor has been reported to be associated with LF. The relationship between serum VD concentration and LF in DM patients has rarely been reported. The aim of this study was to assess the association between serum VD concentration and LF in DM patients. METHODS: In this cross-sectional study, data of DM patients aged ≥ 45 years were extracted from the National Health and Nutrition Examination Survey (NHANES 2017-2018). Serum VD concentration was measured by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Vibration controlled transient elastography (VCTE) was used to measure liver stiffness. Covariates included sociodemographic information, lifestyles, laboratory data, diseases history were extracted from the database. The weighted univariable and multivariable logistic regression models were utilized to explore the association between serum VD concentration and LF in DM patients, and were described as odds ratio (ORs) and 95% confidence intervals (CIs). Subgroup analyses based on BMI, liver steatosis, hypertension and dyslipidemia were further assessed the association. RESULTS: A total of 799 patients were included, of which 188 (23.53%) had LF. Higher serum VD concentration was associated with the lower odds of LF (OR = 0.33, 95% CI 0.19-0.59) and advanced LF (OR = 0.31, 95% CI 0.17-0.55) in DM patients after adjustment for race, liver steatosis, BMI, smoking, drinking, AST, ALT and physical activity, especially in patients with liver steatosis (OR = 0.28, 95% CI 0.13-0.59) and dyslipidemia (OR = 0.31, 95% CI 0.14-0.66), respectively. CONCLUSIONS: High serum VD concentration may have a potential benefit for maintain the liver health in DM patients.

Identification of Small Molecule Inhibitors of PPM1D Using a Novel Drug Discovery Platform.

Protein phosphatase, Mg2+/Mn2+ dependent 1D (PPM1D), is a serine/threonine phosphatase that is recurrently activated in cancer, regulates the DNA damage response (DDR), and suppresses the activation of p53. Consistent with its oncogenic properties, genetic loss or pharmacologic inhibition of PPM1D impairs tumor growth and sensitizes cancer cells to cytotoxic therapies in a wide range of preclinical models. Given the therapeutic potential of targeting PPM1D specifically and the DDR and p53 pathway more generally, we sought to deepen our biological understanding of PPM1D as a drug target and determine how PPM1D inhibition differs from other therapeutic approaches to activate the DDR. We performed a high throughput screen to identify new allosteric inhibitors of PPM1D, then generated and optimized a suite of enzymatic, cell-based, and in vivo pharmacokinetic and pharmacodynamic assays to drive medicinal chemistry efforts and to further interrogate the biology of PPM1D. Importantly, this drug discovery platform can be readily adapted to broadly study the DDR and p53. We identified compounds distinct from previously reported allosteric inhibitors and showed in vivo on-target activity. Our data suggest that the biological effects of inhibiting PPM1D are distinct from inhibitors of the MDM2-p53 interaction and standard cytotoxic chemotherapies. These differences also highlight the potential therapeutic contexts in which targeting PPM1D would be most valuable. Therefore, our studies have identified a series of new PPM1D inhibitors, generated a suite of in vitro and in vivo assays that can be broadly used to interrogate the DDR, and provided important new insights into PPM1D as a drug target.

[The Efficacy and Influencing Factors of Cyclosporine Alone in the Treatment of Children with Acquired Aplastic Anemia].

OBJECTIVE: To analyze the efficacy and influencing factors of cyclosporine (CsA) alone in the treatment of children with acquired aplastic anemia (AA). METHODS: The clinical data of children diagnosed with AA and treated with CsA alone from January 1, 2016 to December 31, 2020 in the Children's Hospital of Chongqing Medical University were collected, and the efficacy and influencing factors of CsA treatment were evaluated. RESULTS: Among the 119 patients, there were 62 male and 57 female, with a median age of 7 years and 1 month. There were 45 cases of very severe AA (VSAA), 47 cases of severe AA (SAA), and 27 cases of non-severe AA (NSAA). At 6 months after treatment, the efficacy of VSAA was lower than that of SAA and NSAA, and there was a statistical difference (P < 0.01). 6 cases died early, 16 cases relapsed, 2 cases progressed to AML and ALL. The results of univariate analysis showed that the high proportion of lymphocyte in the bone marrow at 6 months was an adverse factor for the efficacy of CsA, while high PLT count was a protective factor (P =0.008, P =0.002). The ROC curve showed that the cut-off values of PLT count and the proportion of bone marrow lymphocyte at 6 months were 16.5×109 /L, 68.5%, respectively. Multivariate analysis showed that the high proportion of lymphocyte in bone marrow at 6 months was an independent adverse factor for IST (P =0.020, OR =0.062), and high PLT count was a protective factor (P =0.044, OR =1.038). At 3 months of treatment, CsA response and NSAA were the risk factor for recurrence (P =0.001, 0.031). CONCLUSION: The efficacy of NSAA was higher than that of SAA and VSAA after 6 months of treatment with CsA alone. A high PLT count at the initial diagnosis was a good factor for the effectiveness of CsA, and a high proportion of bone marrow lymphocyte was an unfavorable factor. CsA response at 3 months and NSAA were risk factors for recurrence.

Employing unnatural promiscuity of sortase to construct peptide macrocycle libraries for ligand discovery.

With the increasing attention paid to macrocyclic scaffolds in peptide drug development, genetically encoded peptide macrocycle libraries have become invaluable sources for the discovery of high-affinity peptide ligands targeting disease-associated proteins. The traditional phage display technique of constructing disulfide-tethered macrocycles by cysteine oxidation has the inherent drawback of reduction instability of the disulfide bond. Chemical macrocyclization solves the problem of disulfide bond instability, but the involved highly electrophilic reagents are usually toxic to phages and may bring undesirable side reactions. Here, we report a unique Sortase-mediated Peptide Ligation and One-pot Cyclization strategy (SPLOC) to generate peptide macrocycle libraries, avoiding the undesired reactions of electrophiles with phages. The key to this platform is to mine the unnatural promiscuity of sortase on the X residue of the pentapeptide recognition sequence (LPXTG). Low reactive electrophiles are incorporated into the X-residue side chain, enabling intramolecular cyclization with the cysteine residue of the phage-displayed peptide library. Utilizing the genetically encoded peptide macrocycle library constructed by the SPLOC platform, we found a high-affinity bicyclic peptide binding TEAD4 with a nanomolar KD value (63.9 nM). Importantly, the binding affinity of the bicyclic peptide ligand is 102-fold lower than that of the acyclic analogue. To our knowledge, this is the first time to mine the unnatural promiscuity of ligases to generate peptide macrocycles, providing a new avenue for the construction of genetically encoded cyclic peptide libraries.

Research Note: Pharmacokinetics of bromhexine hydrochloride in broilers after single oral and intravenous administration.

The current study aimed to investigate the pharmacokinetics of bromhexine hydrochloride in broilers after single intravenous (IV) and oral (PO) administration at 2.5 mg/kg body weight (BW). The trial adopted a randomized, parallel-controlled design, where 20 twelve-wk-old broilers were randomly assigned to either the PO or IV group. Blood samples were collected at predetermined time points, and plasma was further separated for analysis. The bromhexine hydrochloride concentrations in plasma samples were determined using an ultra-performance liquid chromatography-tandem quadrupole mass spectrometry (UPLC-MS/MS) method. Noncompartmental analysis (NCA) using Phoenix software was conducted to analyze the concentration versus time data of bromhexine hydrochloride in every chicken. Subsequently, the main pharmacokinetic parameters between the 2 groups were statistically analyzed using SPSS software. Results from NCA revealed that after oral administration at 2.5 mg/kg BW, bromhexine hydrochloride exhibited slow absorption, reaching an average peak concentration of 32.72 ng/mL at 1.78 h. However, incomplete absorption was observed, with an absolute bioavailability of only 20.06% ± 10.84%. Additionally, bromhexine hydrochloride displayed wide distribution, with a steady-state distribution volume (VSS) of 22.55 ± 13.45 L/kg, and slow elimination, with a clearance (Cl) of 1.52 ± 0.38 L/h/kg. Furthermore, gender effects were assessed on the pharmacokinetics of bromhexine hydrochloride in broilers, revealing better absorption in male broilers compared to females. This disparity may be attributed to the faster blood flow and richer blood volume typically found in male broilers.

GATA binding protein 2 mediated ankyrin repeat domain containing 26 high expression in myeloid-derived cell lines.

BACKGROUND: Thrombocytopenia 2, an autosomal dominant inherited disease characterized by moderate thrombocytopenia, predisposition to myeloid malignancies and normal platelet size and function, can be caused by 5'-untranslated region (UTR) point mutations in ankyrin repeat domain containing 26 (ANKRD26). Runt related transcription factor 1 (RUNX1) and friend leukemia integration 1 (FLI1) have been identified as negative regulators of ANKRD26. However, the positive regulators of ANKRD26 are still unknown. AIM: To prove the positive regulatory effect of GATA binding protein 2 (GATA2) on ANKRD26 transcription. METHODS: Human induced pluripotent stem cells derived from bone marrow (hiPSC-BM) and urothelium (hiPSC-U) were used to examine the ANKRD26 expression pattern in the early stage of differentiation. Then, transcriptome sequencing of these iPSCs and three public transcription factor (TF) databases (Cistrome DB, animal TFDB and ENCODE) were used to identify potential TF candidates for ANKRD26. Furthermore, overexpression and dual-luciferase reporter experiments were used to verify the regulatory effect of the candidate TFs on ANKRD26. Moreover, using the GENT2 platform, we analyzed the relationship between ANKRD26 expression and overall survival in cancer patients. RESULTS: In hiPSC-BMs and hiPSC-Us, we found that the transcription levels of ANKRD26 varied in the absence of RUNX1 and FLI1. We sequenced hiPSC-BM and hiPSC-U and identified 68 candidate TFs for ANKRD26. Together with three public TF databases, we found that GATA2 was the only candidate gene that could positively regulate ANKRD26. Using dual-luciferase reporter experiments, we showed that GATA2 directly binds to the 5'-UTR of ANKRD26 and promotes its transcription. There are two identified binding sites of GATA2 that are located 2 kb upstream of the TSS of ANKRD26. In addition, we discovered that high ANKRD26 expression is always related to a more favorable prognosis in breast and lung cancer patients. CONCLUSION: We first discovered that the transcription factor GATA2 plays a positive role in ANKRD26 transcription and identified its precise binding sites at the promoter region, and we revealed the importance of ANKRD26 in many tissue-derived cancers.

Analysis of nearly 3000 archaeal genomes from terrestrial geothermal springs sheds light on interconnected biogeochemical processes.

Terrestrial geothermal springs are physicochemically diverse and host abundant populations of Archaea. However, the diversity, functionality, and geological influences of these Archaea are not well understood. Here we explore the genomic diversity of Archaea in 152 metagenomes from 48 geothermal springs in Tengchong, China, collected from 2016 to 2021. Our dataset is comprised of 2949 archaeal metagenome-assembled genomes spanning 12 phyla and 392 newly identified species, which increases the known species diversity of Archaea by ~48.6%. The structures and potential functions of the archaeal communities are strongly influenced by temperature and pH, with high-temperature acidic and alkaline springs favoring archaeal abundance over Bacteria. Genome-resolved metagenomics and metatranscriptomics provide insights into the potential ecological niches of these Archaea and their potential roles in carbon, sulfur, nitrogen, and hydrogen metabolism. Furthermore, our findings illustrate the interplay of competition and cooperation among Archaea in biogeochemical cycles, possibly arising from overlapping functional niches and metabolic handoffs. Taken together, our study expands the genomic diversity of Archaea inhabiting geothermal springs and provides a foundation for more incisive study of biogeochemical processes mediated by Archaea in geothermal ecosystems.

Groundwater denitrification enhanced by a hydrogel immobilized iron/solid carbon source: impact on denitrification and substrate release performance.

Encapsulating a solid carbon source and zero-valent iron (ZVI) within a hydrogel can prevent direct contact with groundwater, thereby extending the lifespan of their released active substrates. It is currently unclear whether the solid carbon source and ZVI will mutually influence each other's active substrate release process and the corresponding denitrification patterns, necessitating further investigation. In this study a hydrogel encapsulating different weight ratios of micron-sized zero-valent iron (mZVI, as ZVI) and polyhydroxybutyrate (PHB, as a solid carbon source) was synthesized. The aim was to investigate the influence of PHB on the release of dissolved iron from mZVI and denitrification mechanism. Results indicated that PHB was consumed at a higher rate than mZVI, and more mZVI active sites could be exposed after PHB consumption. Meanwhile, PHB increased the porosity of the hydrogel, allowing more active sites of mZVI to be exposed and thus releasing more dissolved iron. Furthermore, PHB enhanced the rate of microbial corrosion of mZVI, which further increased the release of dissolved iron. Higher PHB content in the hydrogel reduced the oxidation of the released dissolved iron, resulting in a microbial community dominated by heterotrophic microorganisms. Conversely, lower PHB content led to significant Fe(II) oxidation and a considerable relative abundance of mixotrophic microorganisms in the microbial community. Microorganisms with iron reduction potential were also detected. This study provides theoretical support for the precise control of mixed nutrient denitrification based on hydrogel immobilization and lays the foundation for its further practical application in groundwater.

A novel small-molecule PCSK9 inhibitor E28362 ameliorates hyperlipidemia and atherosclerosis.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) binds to the epidermal growth factor precursor homologous domain A (EGF-A) of low-density lipoprotein receptor (LDLR) in the liver and triggers the degradation of LDLR via the lysosomal pathway, consequently leading to an elevation in plasma LDL-C levels. Inhibiting PCSK9 prolongs the lifespan of LDLR and maintains cholesterol homeostasis in the body. Thus, PCSK9 is an innovative pharmacological target for treating hypercholesterolemia and atherosclerosis. In this study, we discovered that E28362 was a novel small-molecule PCSK9 inhibitor by conducting a virtual screening of a library containing 40,000 compounds. E28362 (5, 10, 20 µM) dose-dependently increased the protein levels of LDLR in both total protein and the membrane fraction in both HepG2 and AML12 cells, and enhanced the uptake of DiI-LDL in AML12 cells. MTT assay showed that E28362 up to 80 µM had no obvious toxicity in HepG2, AML12, and HEK293a cells. The effects of E28362 on hyperlipidemia and atherosclerosis were evaluated in three different animal models. In high-fat diet-fed golden hamsters, administration of E28362 (6.7, 20, 60 mg·kg-1·d-1, i.g.) for 4 weeks significantly reduced plasma total cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C) and PCSK9 levels, and reduced liver TC and TG contents. In Western diet-fed ApoE-/- mice (20, 60 mg·kg-1·d-1, i.g.) and human PCSK9 D374Y overexpression mice (60 mg·kg-1·d-1, i.g.), administration of E28362 for 12 weeks significantly decreased plasma LDL-C levels and the area of atherosclerotic lesions in en face aortas and aortic roots. Moreover, E28362 significantly increased the protein expression level of LDLR in the liver. We revealed that E28362 selectively bound to PCSK9 in HepG2 and AML12 cells, blocked the interaction between LDLR and PCSK9, and induced the degradation of PCSK9 through the ubiquitin-proteasome pathway, which finally resulted in increased LDLR protein levels. In conclusion, E28362 can block the interaction between PCSK9 and LDLR, induce the degradation of PCSK9, increase LDLR protein levels, and alleviate hyperlipidemia and atherosclerosis in three distinct animal models, suggesting that E28362 is a promising lead compound for the treatment of hyperlipidemia and atherosclerosis.

Nuclear-targeted chimeric peptide nanorods to amplify innate anti-tumor immunity through localized DNA damage and STING activation.

Stimulator of the interferon genes (STING) pathway is appealing but challenging to potentiate the innate anti-tumor immunity. In this work, nuclear-targeted chimeric peptide nanorods (designated as PFPD) are constructed to amplify innate immunity through localized DNA damage and STING activation. Among which, the chimeric peptide (PpIX-FFVLKPKKKRKV) is fabricated with photosensitizer and nucleus targeting peptide sequence, which can self-assemble into nanorods and load STING agonist of DMXAA. The uniform nanosize distribution and good stability of PFPD improve the sequential targeting delivery of drugs towards tumor cells and nuclei. Under light irradiation, PFPD produce a large amount of reactive oxygen species (ROS) to destroy nuclear DNA in situ, and the released cytosolic DNA fragment will efficiently activate innate anti-tumor immunity in combination with STING agonist. In vitro and in vivo results indicate the superior ability of PFPD to activate natural killer cells and T cells, thus efficiently eradicating lung metastatic tumor without inducing unwanted side effects. This work provides a sophisticated strategy for localized activation of innate immunity for systemic tumor treatment, which may inspire the rational design of nanomedicine for tumor precision therapy.

A high-throughput differential scanning fluorimetry method for rapid detection of thermal stability and iron saturation in lactoferrin.

Thermal stability and iron saturation of lactoferrin (LF) are of great significance not only for the evaluation of the biological activities of LF but also for the optimization of the isolation and drying process parameters. Differential scanning calorimetry (DSC) is a well-established and efficient method for thermal stability and iron saturation detection in LF. However, multiple DSC measurements are typically performed sequentially, thus time-consuming and low throughput. Herein, we introduced the differential scanning fluorimetry (DSF) approach to overcome such limitations. The DSF can monitor LF thermal unfolding with a commonly available real-time PCR instrument and a fluorescent dye (SYPRO orange or Glomelt), and the measured melting temperature of LF is consistent with that determined by DSC. On the basis of that, a new quantification method was established for determination of iron saturation levels using the linear correlation of the degree of ion saturation of LF with DSF measurements. Such DSF method is simple, inexpensive, rapid (<15 min), and high throughput (>96 samples per experiment), and provides a valuable alternative tool for thermal stability detection of LF and other whey proteins.