Generation of green fluorescent protein reporter knock-in iPSC line at the 3'UTR region of the KLOTHO locus.

We generated a human induced pluripotent stem cell (hiPSC) line (CMCi014-A-78) expressing a GFP reporter in the 3'-UTR region of the KLOTHO locus using CRISPR/Cas9-mediated homologous recombination to screen for candidates regulating KLOTHO. The established cell line exhibits a normal karyotype, typical stem cell morphology, expression of pluripotency markers, and the ability to differentiate into the three germ layers. Consequently, this hiPSC line could serve as a valuable resource for screening KLOTHO regulators in hiPSC-derived target cells or organoids.

CRISPR/Cas9-mediated suppression of A4GALT rescues endothelial cell dysfunction in a fabry disease vasculopathy model derived from human induced pluripotent stem cells.

BACKGROUND AND AIMS: The objective of this study was to investigate the efficacy of CRISPR/Cas9-mediated A4GALT suppression in rescuing endothelial dysfunction in Fabry disease (FD) endothelial cells (FD-ECs) derived from human induced pluripotent stem cells (hiPSCs). METHODS: We differentiated hiPSCs (WT (wild-type), WTC-11), GLA-mutant hiPSCs (GLA-KO, CMC-Fb-002), and CRISPR/Cas9-mediated A4GALT-KO hiPSCs (GLA/A4GALT-KO, Fb-002-A4GALT-KO) into ECs and compared FD phenotypes and endothelial dysfunction. We also analyzed the effect of A4GALT suppression on reactive oxygen species (ROS) formation and transcriptome profiles through RNA sequencing. RESULTS: GLA-mutant hiPSC-ECs (GLA-KO and CMC-Fb-002) showed downregulated expression of EC markers and significantly reduced α-GalA expression with increased Gb-3 deposition and intra-lysosomal inclusion bodies. However, CRISPR/Cas9-mediated A4GALT suppression in GLA/A4GALT-KO and Fb-002-A4GALT-KO hiPSC-ECs increased expression levels of EC markers and rescued these FD phenotypes. GLA-mutant hiPSC-ECs failed to form tube-like structure in tube formation assays, showing significantly decreased migration of cells into the scratched wound area. In contrast, A4GALT suppression improved tube formation and cell migration capacity. Western blot analysis revealed that MAPK and AKT phosphorylation levels were downregulated while SOD and catalase were upregulated in GLA-KO hiPSC-ECs. However, suppression of A4GALT restored these protein alterations. RNA sequencing analysis demonstrated significant transcriptome changes in GLA-mutant EC, especially in angiogenesis, cell death, and cellular response to oxidative stress. However, these were effectively restored in GLA/A4GALT-KO hiPSC-ECs. CONCLUSIONS: CRISPR/Cas9-mediated A4GALT suppression rescued FD phenotype and endothelial dysfunction in GLA-mutant hiPSC-ECs, presenting a potential therapeutic approach for FD-vasculopathy.

Enhanced photocatalytic performance of NiFe2O4/ZnIn2S4 p-n heterojunction for efficient degradation of tetracycline.

The persistent release of tetracycline into the environment significantly endangers both ecosystems and human health. Zinc indium sulfide (ZnIn2S4) capable to degrade tetracycline pollutants under visible light irradiation has attracted extensive attentions and great effort has been devoted to augment its catalytic efficacy. In this work, we synthesized a p-n heterojunction, NiFe2O4/ZnIn2S4, to enhance the carrier migration rate and explained the intrinsic mechanism by density functional theory. When the heterojunction was formed, carriers traversed from the n-type NiFe2O4 to the p-type ZnIn2S4, instigating the emergence of a built-in electric field to facilitate the separation of carriers. 2 %-NiFe2O4/ZnIn2S4 exhibited excellent photocatalytic efficiency in tetracycline (TC) degradation and total organic carbon (TOC) removal. Compared to pure ZnIn2S4 and NiFe2O4, the TC degradation rates of 2 %-NiFe2O4/ZnIn2S4 were 2.0 times and 16.9 times higher, respectively. Additionally, 2 %-NiFe2O4/ZnIn2S4 had a saturation magnetization intensity of 3.05 emu/g, allowing for rapid recovery of the catalyst under a magnetic field. Superoxide radicals (O2-) and holes (h+) were the primary active species driving the degradation process. Furthermore, potential reaction pathways of tetracycline in this photocatalytic process were determined and bioconcentration factor and developmental toxicity of the intermediate products were accessed. This work held great potentials for wastewater treatment and provided a pathway for the development of magnetic recyclable photocatalysts.

Advancements in Research on Genetic Kidney Diseases Using Human-Induced Pluripotent Stem Cell-Derived Kidney Organoids.

Genetic or hereditary kidney disease stands as a pivotal cause of chronic kidney disease (CKD). The proliferation and widespread utilization of DNA testing in clinical settings have notably eased the diagnosis of genetic kidney diseases, which were once elusive but are now increasingly identified in cases previously deemed CKD of unknown etiology. However, despite these diagnostic strides, research into disease pathogenesis and novel drug development faces significant hurdles, chiefly due to the dearth of appropriate animal models and the challenges posed by limited patient cohorts in clinical studies. Conversely, the advent and utilization of human-induced pluripotent stem cells (hiPSCs) offer a promising avenue for genetic kidney disease research. Particularly, the development of hiPSC-derived kidney organoid systems presents a novel platform for investigating various forms of genetic kidney diseases. Moreover, the integration of the CRISPR/Cas9 technique into this system holds immense potential for efficient research on genetic kidney diseases. This review aims to explore the applications of in vitro kidney organoids generated from hiPSCs in the study of diverse genetic kidney diseases. Additionally, it will delve into the limitations of this research platform and outline future perspectives for advancing research in this crucial area.

Nuclear Receptor Subfamily 4 Group A Member 1 (NR4A1) Promotes the Adipogenesis of Intramuscular Preadipocytes through PI3K/AKT Pathway in Goats.

As a transcription factor, Nuclear Receptor Subfamily 4 Group A Member 1 (NR4A1) binds to downstream target genes to participate in cell proliferation and cell differentiation. We found that the NR4A1 reached the highest expression at 60 h after the differentiation of goat intramuscular preadipocytes. Overexpression of goat NR4A1 increased the number of intracellular lipid droplets and up-regulated the expression of adipocyte-differentiation-related marker genes including AP2, SREBP1, ACC, GPAM, and DGAT2, while the relative expression levels of Pref-1 and HSL were significantly decreased. On the contrary, after NR4A1 was knocked down by siRNA, the number of intracellular lipid droplets and the relative expression levels of LPL, CEBPα, CEBPß, ACC, and DGAT2 were significantly decreased, and the relative expression levels of Pref-1 and HSL were significantly up-regulated. These results suggest that NR4A1 promotes the differentiation of goat intramuscular preadipocytes. Transcriptome sequencing was carried out after overexpression of goat NR4A1, and the KEGG enrichment analysis result showed that the most differentially expressed genes were related to adipocyte differentiation and were enriched in the PI3K-Akt signaling pathway. LY249002, an inhibitor of the PI3K-Akt signaling pathway, was introduced and decreased the number of intracellular lipid droplets, and the relative expression levels of C/EBPα, SREBP1, AP2, C/EBPß, GPAM, ACC, DGAT1, DGAT2, and ATGL were decreased accordingly. The above results indicate that overexpression of goat NR4A1 may promote the differentiation of intramuscular preadipocytes through the PI3K-Akt signaling pathway.

Nucleic acid-induced NADase activation of a short Sir2-associated prokaryotic Argonaute system.

Inhibition of nucleic acid targets is mediated by Argonaute (Ago) proteins guided by RNA or DNA. Although the mechanisms underpinning the functions of eukaryotic and "long" prokaryotic Ago proteins (pAgos) are well understood, those for short pAgos remain enigmatic. Here, we determine two cryoelectron microscopy structures of short pAgos in association with the NADase-domain-containing protein Sir2-APAZ from Geobacter sulfurreducens (GsSir2/Ago): the guide RNA-target DNA-loaded GsSir2/Ago quaternary complex (2.58 Å) and the dimer of the quaternary complex (2.93Å). These structures show that the nucleic acid binding causes profound conformational changes that result in disorder or partial dissociation of the Sir2 domain, suggesting that it adopts a NADase-active conformation. Subsequently, two RNA-/DNA-loaded GsSir2/Ago complexes form a dimer through their MID domains, further enhancing NADase activity through synergistic effects. The findings provide a structural basis for short-pAgo-mediated defense against invading nucleic acids.

Design, Synthesis, and Biological Evaluation of 1,2,4-Oxadiazole Derivatives Containing an Aryl Carboxylic Acid Moiety as Potent Sarbecovirus Papain-like Protease Inhibitors.

Papain-like protease (PLpro) is a promising therapeutic target for its pivotal role in the life cycle of SARS-CoV-2. A series of 1,2,4-oxadiazole derivatives was designed and synthesized via a ring formation strategy based on SARS-CoV-2 PLpro-GRL0617 complex structure. Systematic structure-activity relationship studies revealed that introducing oxadiazole and aryl carboxylic acid moieties to GRL0617 enhanced the enzymatic inhibition activity, affinity, and deubiquitination capacity toward PLpro. 1,2,4-Oxadiazole compounds 13f and 26r, which had PLpro inhibition activity (IC50 = 1.8 and 1.0 µM) and antiviral activity against SARS-CoV-2 (EC50 = 5.4 and 4.3 µM), exhibited good metabolic stability (t1/2 > 93.2 min) and higher plasma exposure (AUC0-t = 17,380.08 and 24,289.76 ng·h/mL) in mice. Especially, compound 26r with moderate oral bioavailability of 39.1% and potent antiviral activity is worthy of further studies in vivo. Our findings provide a new insight for the discovery of antiviral agents targeting PLpro.

Single-cell RNA sequencing revealed the role of the Th17 pathway in the development of anti- human leukocyte antigen antibodies in a highly sensitized mouse model.

Background: The aim of this study is to investigate the specific pathway involved in human leukocyte antigen (HLA) sensitization using single-cell RNA-sequencing analysis and an allo-sensitized mouse model developed with an HLA.A2 transgenic mouse. Methods: For sensitization, wild-type C57BL/6 mouse received two skin grafts from C57BL/6-Tg(HLA-A2.1)1Enge/J mouse (allogeneic mouse, ALLO). For syngeneic control (SYN), skin grafts were transferred from C57BL/6 to C57BL/6. We performed single-cell RNA-sequencing analysis on splenocytes isolated from ALLO and SYN and compared the gene expression between them. Results: We generated 9,190 and 8,890 single-cell transcriptomes from ALLO and SYN, respectively. Five major cell types (B cells, T cells, natural killer cells, macrophages, and neutrophils) and their transcriptome data were annotated according to the representative differentially expressed genes of each cell cluster. The percentage of B cells was higher in ALLO than it was in SYN. Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated that the highly expressed genes in the B cells from ALLO were mainly associated with antigen processing and presentation pathways, allograft rejection, and the Th17 cell differentiation pathway. Upregulated genes in the T cells of ALLO were involved in the interleukin (IL)-17 signaling pathway. The ratio of Th17 cluster and Treg cluster was increased in the ALLO. On flow cytometry, the percentage of Th17 (IL-17+/CD4+ T) cells was higher and regulatory T cells (FOXP3+/CD4+ T) was lower in the ALLO compared to those in the SYN. Conclusion: Our results indicate that not only the B cell lineage but also the Th17 cells and their cytokine (IL-17) are involved in the sensitization to HLA.

Ag Nanoparticles Deposited onto BaTiO3 Aerogel for Highly Efficient Photodegradation.

Given the increasingly severe environmental problems caused by water pollution, the degradation of organic dyes can be effectively achieved through the utilization of photocatalysis. In this work, metal alkoxides and a combination of alcohol/hydrophobic solvents are employed to prepare BaTiO3 aerogels via a liquid-phase and template-free synthetic route. The preparation process of the aerogels solely entails facile agitation and supercritical drying, eliminating the need for additional heat treatment. The binary solvent of ethanol and toluene is identified as the optimal choice, resulting in a significantly enhanced surface area (up to 223 m2/g) and an abundant pore structure of BaTiO3 aerogels compared to that of the BaTiO3 nanoparticles. Thus, the removal efficiency of the BaTiO3 aerogel sample for MO is nearly twice as high as that of the BaTiO3 nanoparticles sample. Noble metal Ag nanoparticles' deposition onto the BaTiO3 aerogel surface is further achieved via the photochemical deposition method, which enhances the capture of photogenerated electrons, thereby ensuring an elevated level of photocatalytic efficiency. As a result, Ag nanoparticles deposited on BaTiO3 aerogel can degrade MO completely after 40 min of illumination, while the corresponding aerogel before modification can only remove 80% of MO after 60 min. The present work not only complements the preparatory investigation of intricate aerogels but also offers a fresh perspective for the development of diverse perovskite aerogels with broad applications.

Electric Field Effect of the Plasma-Initiated Polymerization of Methyl Methacrylate: A Negatively Charged Long-Lived Radical.

Plasma-initiated polymerization (PIP) is generally attributed to a radical process due to its inhibiting property. However, its unique polymerization behaviors like long-lived radical and solvent effect do not comply well with the traditional radical mechanism. Herein, the PIP of methyl methacrylate (MMA) was conducted in a high-voltage DC electric field to investigate the charged nature of its radicals. Consequently, the polymerization presented a preferential distribution of polymers at the anode but not the cathode, revealing the negatively charged nature of the growing radicals. An acceleration phenomenon, accompanied by the growth in molecular weights and the reduction in molecular weight distributions (Ð), was observed at the voltages above 16 kV, suggesting the dissociation of ion pairs of growing radicals. The PIP yielded PMMA with analogous chemical and steric structures to those of PMMA from traditional radical initiation, whether in the presence or absence of the external electric field. This work offers new insights into the PIP of vinyl monomers, wherein a one-electron transfer reaction is inferred to be involved in the monomer activation.

The EV71 2A protease occupies the central cleft of SETD3 and disrupts SETD3-actin interaction.

SETD3 is an essential host factor for the replication of a variety of enteroviruses that specifically interacts with viral protease 2A. However, the interaction between SETD3 and the 2A protease has not been fully characterized. Here, we use X-ray crystallography and cryo-electron microscopy to determine the structures of SETD3 complexed with the 2A protease of EV71 to 3.5 Å and 3.1 Å resolution, respectively. We find that the 2A protease occupies the V-shaped central cleft of SETD3 through two discrete sites. The relative positions of the two proteins vary in the crystal and cryo-EM structures, showing dynamic binding. A biolayer interferometry assay shows that the EV71 2A protease outcompetes actin for SETD3 binding. We identify key 2A residues involved in SETD3 binding and demonstrate that 2A's ability to bind SETD3 correlates with EV71 production in cells. Coimmunoprecipitation experiments in EV71 infected and 2A expressing cells indicate that 2A interferes with the SETD3-actin complex, and the disruption of this complex reduces enterovirus replication. Together, these results reveal the molecular mechanism underlying the interplay between SETD3, actin, and viral 2A during virus replication.

Fabrication of the SiC/HfC Composite Aerogel with Ultra-Low Thermal Conductivity and Excellent Compressive Strength.

Aerogels, as a new type of high-temperature-resistant insulation material, find extensive application in aerospace, high-temperature industrial furnaces, new energy batteries, and various other domains, yet still face some limitations such as inadequate temperature resistance and pronounced brittleness. In this work, SiC/HfC composite aerogels were prepared through a combination of sol-gel method, atmospheric pressure drying technique, and carbothermal reduction reaction. The effects of different molar ratios, calcination time, and temperatures on the microstructural features and physicochemical properties of the resulting SiC/HfC composite aerogels were investigated. The aerogel exhibited an elevated BET-specific surface area of 279.75 m2/g, while the sample displayed an extraordinarily low thermal conductivity of 0.052 W/(m·K). Most notably, the compressive strength reached an outstanding 5.93 MPa after a carbonization temperature of 1500 °C, far exceeding the values reported in prior aerogel studies. This research provided an innovative approach for advancing the development of carbide aerogels in the realm of high-temperature applications.

Ag-Incorporated Cr-Doped BaTiO3 Aerogel toward Enhanced Photocatalytic Degradation of Methyl Orange.

A novel Cr-doped BaTiO3 aerogel was successfully synthesized using a co-gelation technique that involves two metallic alkoxides and a supercritical drying method. This freshly prepared aerogel has a high specific surface area of over 100 m2/g and exhibits improved responsiveness to the simulated sunlight spectrum. Methyl orange (MO) was chosen as the simulated pollutant, and the results reveal that the Cr-doped BaTiO3 aerogel, when modified with the noble metal silver (Ag), achieves a pollutant removal rate approximately 3.2 times higher than that of the commercially available P25, reaching up to 92% within 60 min. The excellent photocatalytic performance of the Ag-modified Cr-doped BaTiO3 aerogel can be primarily attributed to its extensive specific surface area and three-dimensional porous architecture. Furthermore, the incorporation of Ag nanoparticles effectively suppresses the recombination of photo-generated electrons and holes. Stability and reusability tests have confirmed the reliability of the Ag-modified Cr-doped BaTiO3 aerogel. Therefore, this material emerges as a highly promising candidate for the treatment of textile wastewater.

Quantitative evaluation of vertical control in orthodontic camouflage treatment for skeletal class II with hyperdivergent facial type.

BACKGROUND: In this study, we sought to quantify the influence of vertical control assisted by a temporary anchorage device (TAD) on orthodontic treatment efficacy for skeletal class II patients with a hyperdivergent facial type and probe into the critical factors of profile improvement. METHODS: A total of 36 adult patients with skeletal class II and a hyperdivergent facial type were included in this retrospective case-control study. To exclude the effect of sagittal anchorage reinforcement, the patients were divided into two groups: a maxillary maximum anchorage (MMA) group (N = 17), in which TADs were only used to help with anterior tooth retraction, and the MMA with vertical control (MMA + VC) group (N = 19), for which TADs were also used to intrude the maxillary molars and incisors. The treatment outcome was evaluated using dental, skeletal, and soft-tissue-related parameters via a cephalometric analysis and cast superimposition. RESULTS: A significant decrease in ANB (P < 0.05 for both groups), the retraction and uprighting of the maxillary and mandibular incisors, and the retraction of protruded upper and lower lips were observed in both groups. Moreover, a significant intrusion of the maxillary molars was observed via the cephalometric analysis (- 1.56 ± 1.52 mm, P < 0.05) and cast superimposition (- 2.25 ± 1.03 mm, P < 0.05) of the MMA + VC group but not the MMA group, which resulted in a remarkable decrease in the mandibular plane angle (- 1.82 ± 1.38°, P < 0.05). The Z angle (15.25 ± 5.30°, P < 0.05) and Chin thickness (- 0.97 ± 0.45°, P < 0.05) also improved dramatically in the MMA + VC group, indicating a better profile and a relaxed mentalis. Multivariate regression showed that the improvement in the soft tissue was closely related to the counterclockwise rotation of the mandible plane (P < 0.05). CONCLUSIONS: TAD-assisted vertical control can achieve intrusion of approximately 2 mm for the upper first molars and induce mandibular counterclockwise rotation of approximately 1.8°. Moreover, it is especially important for patients without sufficient retraction of the upper incisors or a satisfactory chin shape.

Correction: Enterovirus 71 Protease 2Apro Targets MAVS to Inhibit Anti-Viral Type I Interferon Responses.

[This corrects the article DOI: 10.1371/journal.ppat.1003231.].

Taurine Alleviates Experimental Colitis by Enhancing Intestinal Barrier Function and Inhibiting Inflammatory Response through TLR4/NF-κB Signaling.

Taurine (Tau) is a semiessential amino acid in mammals with preventive and therapeutic effects on several intestinal disorders. However, the exact function of taurine in ulcerative colitis (UC) is still largely unclear. In this study, we used two taurine-deficient mouse models (CSAD-/- and TauT-/- mice) to explore the influence of taurine on the progression of UC in both dextran sulfate sodium (DSS)-induced colitis and LPS-stimulated Caco-2 cells. We found that cysteine sulfinic acid decarboxylase (CSAD) and taurine transporter (TauT) expressions and taurine levels were markedly reduced in colonic tissues of mice treated with DSS. The CSAD and TauT knockouts exacerbated DSS-induced clinical symptoms and pathological damage and aggravated the intestinal barrier dysfunction and the colonic mucosal inflammatory response. Conversely, taurine pretreatment enhanced the intestinal barrier functions by increasing goblet cells and upregulating tight junction protein expression. Importantly, taurine bound with TLR4 and inhibited the TLR4/NF-κB pathway, ultimately reducing proinflammatory factors (TNF-α and IL-6) and oxidative stress. Our findings highlight the essential role of taurine in maintaining the intestinal barrier integrity and inhibiting intestinal inflammation, indicating that taurine is a promising supplement for colitis treatment.

Performance Enhancement of Silicone Rubber Using Superhydrophobic Silica Aerogel with Robust Nanonetwork Structure and Outstanding Interfacial Effect.

The application of high-performance rubber nanocomposites has attracted wide attention, but its development is limited by the imbalance of interface and network effects caused by fillers. Herein, an ultrastrong polymer nanocomposite is successfully designed by introducing a superhydrophobic and mesoporous silica aerogel (HSA) as the filler to poly(methyl vinyl phenyl) siloxane (PVMQ), which increased the PVMQ elongation at break (∼690.1%) by ∼9.3 times and the strength at break (∼6.6 MPa) by ∼24.3 times. Furthermore, HSA/PVMQ with a high dynamic storage modulus (G'0) of ∼12.2 MPa and high Payne effect (ΔG') of ∼9.4 MPa is simultaneously achieved, which is equivalent to 2-3 times that of commercial fumed silica reinforced PVMQ. The superior performance is attributed to the filler-rubber interfacial interaction and the robust filler-rubber entanglement network which is observed by scanning electron microscopy. When the HSA-PVMQ entanglement network is subjected to external stress, both the HSA and bound-PVMQ chains are synergistically involved in resisting structural evolution, resulting in the maximized energy dissipation and deformation resistance through the desorption of the polymer chain and the slip/interpenetrating of the exchange hydrogen bond pairs. Hence, highly aggregated nanoporous silica aerogels may soon be widely used in the application of reinforced silicone rubber or other polymers shortly.

Insomnia and anxiety among COVID-19 patients in China: the chain mediating effect of psychological capital and self-esteem.

BACKGROUND: The outbreak of Corona Virus Disease (COVID-19) in 2019 has continued until now, posing a huge threat to the public's physical and mental health, resulting in different degrees of mental health problems. As a vulnerable segment of the public, anxiety is one of the most common mental health problems among COVID-19 patients. Excessive anxiety aggravates the physical and psychological symptoms of COVID-19 patients, which is detrimental to their treatment and recovery, increases financial expenditure, affects family relations, and adds to the medical burden. OBJECTIVE: This study aimed to explore the role of psychological capital and self-esteem in the relationship between insomnia and anxiety, thereby shedding light on the mechanism of the effect of insomnia on anxiety in COVID-19 patients. METHODS: A cross-sectional study was conducted from April to May 2022 in Fangcang hospital in Shanghai, China. The self-administered questionnaires were distributed to 718 COVID-19 patients via cell phone using the Internet platform "Questionnaire Star", which included Athens Insomnia Scale, Psychological Capital Questionnaire, Self-esteem Scale, Self-Rating Anxiety Scale, gender, age, marital status, education. Data analysis was performed using descriptive analysis, independent-samples t-test, one-way analysis of variance, Pearson correlation analysis, ordinary least-squares regression, and bootstrap method. RESULTS: Education background had significant impact on anxiety in COVID-19 patients (F = 7.70, P < 0.001). Insomnia, psychological capital, self-esteem and anxiety were significantly correlated, respectively (P < 0.001). And Regression analysis showed that insomnia had a direct negative predictive effect on psychological capital (ß = -0.70, P < 0.001) and self-esteem (ß = -0.13, P < 0.001). Psychological capital had a direct positive predictive effect on self-esteem (ß = 0.12, P < 0.001). Insomnia had a direct positive predictive effect on anxiety (ß = 0.61, P < 0.001). Both psychological capital and self-esteem had significant negative predictive effects on anxiety (ß = -0.06, P < 0.05; ß = -0.72, P < 0.001). The results showed that the mediating effect of psychological capital and self-esteem was significant, and the mediating effect value was 0.21. First, the indirect effect consisting of insomnia - psychological capital - anxiety was 0.04, showing that psychological capital had a significant mediating effect. Second, the indirect effect consisting of insomnia-self-esteem-anxiety had a value of 0.10, indicating that self-esteem had a significant mediating effect. Third, the indirect effect consisting of insomnia-psychological capital-self-esteem-anxiety had a value of 0.06, suggesting that psychological capital and self-esteem had a significant chain mediating effect between insomnia and anxiety. CONCLUSIONS: Insomnia had a significant positive predictive effect on anxiety. Insomnia was first associated with a decrease in psychological capital, followed by a sequential decrease in self-esteem, which in turn was associated with increased anxiety symptoms in COVID-19 patients. Therefore, focusing on improving the psychological capital and self-esteem of patients can help alleviate the anxiety caused by insomnia in COVID-19 patients. It is recommended that patients and health care professionals increase the psychological capital and Self-esteem of COVID-19 patients through various methods to counter the effects of insomnia on anxiety.

Intestinal melatonin levels and gut microbiota homeostasis are independent of the pineal gland in pigs.

Introduction: Melatonin (MEL) is a crucial neuroendocrine hormone primarily produced by the pineal gland. Pinealectomy (PINX) has been performed on an endogenous MEL deficiency model to investigate the functions of pineal MEL and its relationship with various diseases. However, the effect of PINX on the gastrointestinal tract (GIT) MEL levels and gut microbiome in pigs has not been previously reported. Methods: By using a newly established pig PINX model, we detected the levels of MEL in the GIT by liquid chromatography-tandem mass spectrometry. In addition, we examined the effects of PINX on the expression of MEL synthesis enzymes, intestinal histomorphology, and the intestinal barrier. Furthermore, 16S rRNA sequencing was performed to analyze the colonic microbiome. Results: PINX reduced serum MEL levels but did not affect GIT MEL levels. Conversely, MEL supplementation increased MEL levels in the GIT and intestinal contents. Neither PINX nor MEL supplementation had any effect on weight gain, organ coefficient, serum biochemical indexes, or MEL synthetase arylalkylamine N-acetyltransferase (AANAT) expression in the duodenum, ileum, and colon. Furthermore, no significant differences were observed in the intestinal morphology or intestinal mucosal barrier function due to the treatments. Additionally, 16S rRNA sequencing revealed that PINX had no significant impact on the composition of the intestinal microbiota. Nevertheless, MEL supplementation decreased the abundance of Fibrobacterota and increased the abundance of Actinobacteriota, Desulfobacterota, and Chloroflexi. Conclusion: We demonstrated that synthesis of MEL in the GIT is independent of the pineal gland. PINX had no influence on intestinal MEL level and microbiota composition in pigs, while exogenous MEL alters the structure of the gut microbiota.