Dysregulation of the Gut Microbiota Contributes to Sevoflurane-Induced Cognitive Dysfunction in Aged Mice by Activating the NLRP3 Inflammasome.

Postoperative cognitive dysfunction (POCD), a common complication in elderly patients after surgery, seriously affects patients' quality of life. Long-term or repeated inhalation of sevoflurane can cause neuroinflammation, which is a risk factor for POCD. However, the underlying mechanism needs to be further explored. Recent research had revealed a correlation between neurological disorders and changes in the gut microbiota. Dysfunction of the gut microbiota is involved in the occurrence and development of central nervous system diseases. Here, we found that cognitive dysfunction in aged mice induced by sevoflurane exposure (3%, 2 hours daily, for 3 days) was related to gut microbiota dysbiosis, while probiotics improved cognitive function by alleviating dysbiosis. Sevoflurane caused a significant decrease in the abundance of Akkermansia (P<0.05), while probiotics restored the abundance of Akkermansia. Compared to those in the control group, sevoflurane significantly increased the expression of NLRP3 inflammasome-associated proteins in the gut and brain in the sevoflurane-exposed group, thus causing neuroinflammation and synaptic damage, which probiotics can mitigate (con vs. sev, P < 0.01; p+sev vs. sev, P < 0.05). In conclusion, for the first time, our study revealed that dysbiosis of the gut microbiota caused by sevoflurane anesthesia contributes to the NLRP3 inflammasome-mediated neuroinflammation and cognitive dysfunction from the perspective of the gut-brain axis. Perhaps postoperative cognitive impairment in elderly patients can be alleviated or even prevented by regulating the gut microbiota. This study provides new insights and methods for the prevention and treatment of cognitive impairment induced by sevoflurane.

Influence of moderate-to-high intensity physical activity on depression levels: a study based on a health survey of Chinese university students.

OBJECTIVE: The study aims to examine how moderate-to-vigorous physical activity (MVPA) affects the severity of depression symptoms among Chinese college students. Additionally, it seeks to analyze the mediating mechanisms involving self-rated health and general self-efficacy. METHODS: The study utilized data from the 2023 Chinese College Health Tracking Survey and employed multiple linear regression and structural equation modeling techniques to investigate the impacts of MVPA on depression levels and its underlying mediating mechanisms among college students. The primary cohort comprised 49,717 enrolled college students from 106 universities in China. RESULTS: A total of 41,620 valid questionnaires were collected (response rate: 83.7%), with females accounting for 58.6%. In the past month, approximately 30.2% of college students engaged in MVPA. Self-rated health (B = - 0.282, P < 0.001) and general self-efficacy (B = - 0.133, P < 0.001) significantly influenced college students' depression scores. Even after controlling for other variables, participating in MVPA remained significantly associated with reduced depression scores (B = - 0.062, P = 0.002). The results of the structural equation model showed that MVPA not only directly decreased college students' depression scores but also indirectly reduced the likelihood of depression occurrence by improving their physical health status and general self-efficacy. CONCLUSION: The lack of physical activity among Chinese college students is evident. Engaging in MVPA can reduce the likelihood of depression among college students. MVPA achieves this reduction by enhancing college students' general self-efficacy and improving their physical health. The factors influencing depression levels among college students are multifaceted. For future interventions targeting college students' mental health, comprehensive approaches that incorporate behavioral and psychological factors should be emphasized.

Infection may play an important role in the pathogenesis of alveolar osteonecrosis following facial herpes zoster: a case report and literature review.

BACKGROUND: Herpes zoster (HZ) is one of the most common skin diseases caused by viruses. Facial HZ develops when the varicella-zoster virus affects the trigeminal nerve, and alveolar osteonecrosis is a rare complication. However, the exact pathogenesis of postherpetic alveolar osteonecrosis remains unclear. CASE DESCRIPTION: We encountered a patient who presented to the dermatology clinic with facial HZ and tooth exfoliation in the upper right jaw, and panoramic radiography revealed decreased bone density and poor alveolar socket healing in his right maxilla. Biopsy of the alveolar process revealed fragments of nonvital lamellar bone, which were devoid of osteoblasts and osteocytes and were surrounded by numerous neutrophils and bacterial aggregates. Thus, the diagnosis of alveolar osteonecrosis following facial HZ was confirmed. He then underwent resection of the osteonecrotic tissue. The pathological findings of postoperative tissue were similar to those of previous biopsies. Varicella-zoster virus and multiple types of bacteria were detected through next-generation sequencing, and the species of bacteria were consistent with the results of bacterial culture. Antibiotics and valaciclovir were administered during the perioperative period. The patient showed good recovery at the 9-month follow-up. CONCLUSIONS: The coexistence of bacterial and viral infection may play an important role in the pathogenesis of alveolar osteonecrosis following HZ. To our knowledge, we are the first to directly explore microbial pathogens in a case of postherpetic alveolar osteonecrosis through next-generation sequencing and bacterial culture. We recommend that oral examinations be carefully conducted for patients who are diagnosed with facial HZ, even if their facial rashes have faded away. We suggest that a prolonged and full-dose antiviral therapy course may be beneficial for the treatment of facial HZ with intraoral lesions. The implementation of dental preventive measures should be considered for patients with facial HZ. The application of antibiotics and excision of necrotic bone may reduce the abundance of bacteria in lesions and improve wound healing.

Multi-omics analyses reveal interactions between the skin microbiota and skin metabolites in atopic dermatitis.

Introduction: Atopic dermatitis (AD) is one of the most common inflammatory skin diseases. Skin microecological imbalance is an important factor in the pathogenesis of AD, but the underlying mechanism of its interaction with humans remains unclear. Methods: 16S rRNA gene sequencing was conducted to reveal the skin microbiota dynamics. Changes in skin metabolites were tracked by LC-MS metabolomics. We then explored the potential mechanism of interaction by analyzing the correlation between skin bacterial communities and metabolites in corresponding skin-associated samples. Results: Samples from 18 AD patients and 18 healthy volunteers (HVs) were subjected to 16S rRNA gene sequencing and LC-MS metabolomics. AD patients had dysbiosis of the skin bacterial community with decreased species richness and evenness. The relative abundance of the genus Staphylococcus increased significantly in AD, while the abundances of the genera Propionibacterium and Brevundimonas decreased significantly. The relative abundance of the genera Staphylococcus in healthy females was significantly higher than those in healthy males, while it showed no difference in AD patients with or without lesions. The effects of AD status, sex and the presence or absence of rashes on the number of differentially abundant metabolites per capita were successively reduced. Multiple metabolites involved in purine metabolism and phenylalanine metabolism pathways (such as xanthosine/xanthine and L-phenylalanine/trans-cinnamate) were increased in AD patients. These trends were much more obvious between female AD patients and female HVs. Spearman correlation analysis revealed that the genus Staphylococcus was positively correlated with various compounds involved in phenylalanine metabolism and purine metabolic pathways. The genera Brevundimonas and Lactobacillus were negatively correlated with various compounds involved in purine metabolism, phenylalanine metabolism and sphingolipid signaling pathways. Discussion: We suggest that purine metabolism and phenylalanine metabolism pathway disorders may play a certain role in the pathogenic mechanism of Staphylococcus aureus in AD. We also found that females are more likely to be colonized by the genus Staphylococcus than males. Differentially abundant metabolites involved in purine metabolism and phenylalanine metabolism pathways were more obvious in female. However, we should notice that the metabolites we detected do not necessarily derived from microbes, they may also origin from the host.

Multi-stimuli-responsive luminescence enabled by crown ether anchored chiral antimony halide phosphors.

Stimuli-responsive optical materials have provided a powerful impetus for the development of intelligent optoelectronic devices. The family of organic-inorganic hybrid metal halides, distinguished by their structural diversity, presents a prospective platform for the advancement of stimuli-responsive optical materials. Here, we have employed a crown ether to anchor the A-site cation of a chiral antimony halide, enabling convenient control and modulation of its photophysical properties. The chirality-dependent asymmetric lattice distortion of inorganic skeletons assisted by a crown ether promotes the formation of self-trapped excitons (STEs), leading to a high photoluminescence quantum yield of over 85%, concomitant with the effective circularly polarized luminescence. The antimony halide enantiomers showcase highly sensitive stimuli-responsive luminescent behaviours towards excitation wavelength and temperature simultaneously, exhibiting a versatile reversible colour switching capability from blue to white and further to orange. In situ temperature-dependent luminescence spectra, time-resolved luminescence spectra and theoretical calculations reveal that the multi-stimuli-responsive luminescent behaviours stem from distinct STEs within zero-dimensional lattices. By virtue of the inherent flexibility and adaptability, these chiral antimony chlorides have promising prospects for future applications in cutting-edge fields such as multifunctional illumination technologies and intelligent sensing devices.

IFT27 regulates the long-term maintenance of photoreceptor outer segments in zebrafish.

Approximately a quarter of Retinitis Pigmentosa (RP) is caused by mutations in transport-related genes in cilia. IFT27 (Intraflagellar Transport 27), a core component of the ciliary intraflagellar transport (IFT) system, has been implicated as a significant pathogenic gene in RP. The pathogenic mechanisms and subsequent pathology related to IFT27 mutations in RP are largely obscure. Here, we utilized TALEN technology to create an ift27 knockout (ift27-/-) zebrafish model. Electroretinography (ERG) detection showed impaired vision in this model. Histopathological examinations disclosed that ift27 mutations cause progressive degeneration of photoreceptors in zebrafish, and this degeneration was late-onset. Immunofluorescence labeling of outer segments showed that rods degenerated before cones, aligning with the conventional characterization of RP. In cultured human retinal pigment epithelial cells, we found that IFT27 was involved in maintaining ciliary morphology. Furthermore, decreased IFT27 expression resulted in the inhibition of the Hedgehog (Hh) signaling pathway, including decreased expression of key factors in the Hh pathway and abnormal localization of the ciliary mediator Gli2. In summary, we generated an ift27-/- zebrafish line with retinal degeneration which mimicked the symptoms of RP patients, highlighting IFT27's integral role in the long-term maintenance of cilia via the Hh signaling pathway. This work may furnish new insights into the treatment or delay of RP caused by IFT27 mutations.

Pathogenic mycobacterium upregulates cholesterol 25-hydroxylase to promote granuloma development via foam cell formation.

Pathogenic mycobacteria orchestrate the complex cell populations known as granuloma that is the hallmark of tuberculosis. Foam cells, a lipid-rich cell-type, are considered critical for granuloma formation; however, the causative factor in foam cell formation remains unclear. Atherosclerosis is a chronic inflammatory disease characterized by the abundant accumulation of lipid-laden-macrophage-derived foam cells during which cholesterol 25-hydroxylase (CH25H) is crucial in foam cell formation. Here, we show that M. marinum (Mm), a relative of M. tuberculosis, induces foam cell formation, leading to granuloma development following CH25H upregulation. Moreover, the Mm-driven increase in CH25H expression is associated with the presence of phthiocerol dimycocerosate, a determinant for Mm virulence and integrity. CH25H-null mice showed decreased foam cell formation and attenuated pathology. Atorvastatin, a recommended first-line lipid-lowering drug, promoted the elimination of M. marinum and concomitantly reduced CH25H production. These results define a previously unknown role for CH25H in controlling macrophage-derived foam cell formation and Tuberculosis pathology.

Multi-Algorithm Analysis Reveals Pyroptosis-Linked Genes as Pancreatic Cancer Biomarkers.

Pancreatic ductal adenocarcinoma (PDAC) is often diagnosed at late stages, limiting treatment options and survival rates. Pyroptosis-related gene signatures hold promise as PDAC prognostic markers, but limited gene pools and small sample sizes hinder their utility. We aimed to enhance PDAC prognosis with a comprehensive multi-algorithm analysis. Using R, we employed natural language processing and latent Dirichlet allocation on PubMed publications to identify pyroptosis-related genes. We collected PDAC transcriptome data (n = 1273) from various databases, conducted a meta-analysis, and performed differential gene expression analysis on tumour and non-cancerous tissues. Cox and LASSO algorithms were used for survival modelling, resulting in a pyroptosis-related gene expression-based prognostic index. Laboratory and external validations were conducted. Bibliometric analysis revealed that pyroptosis publications focus on signalling pathways, disease correlation, and prognosis. We identified 357 pyroptosis-related genes, validating the significance of BHLHE40, IL18, BIRC3, and APOL1. Elevated expression of these genes strongly correlated with poor PDAC prognosis and guided treatment strategies. Our accessible nomogram model aids in PDAC prognosis and treatment decisions. We established an improved gene signature for pyroptosis-related genes, offering a novel model and nomogram for enhanced PDAC prognosis.

Antibody and transcription landscape in peripheral blood mononuclear cells of elderly adults over 70 years of age with third dose of COVID-19 BBIBP-CorV and ZF2001 booster vaccine.

BACKGROUND: In the context of the COVID-19 pandemic and extensive vaccination, it is important to explore the immune response of elderly adults to homologous and heterologous booster vaccines of COVID-19. At this point, we detected serum IgG antibodies and PBMC sample transcriptome profiles in 46 participants under 70 years old and 25 participants over 70 years old who received the third dose of the BBIBP-CorV and ZF2001 vaccines. RESULTS: On day 7, the antibody levels of people over 70 years old after the third dose of booster vaccine were lower than those of young people, and the transcriptional responses of innate and adaptive immunity were also weak. The age of the participants showed a significant negative correlation with functions related to T-cell differentiation and costimulation. Nevertheless, 28 days after the third dose, the IgG antibodies of elderly adults reached equivalence to those of younger adults, and immune-related transcriptional regulation was significantly improved. The age showed a significant positive correlation with functions related to "chemokine receptor binding", "chemokine activity", and "chemokine-mediated signaling pathway". CONCLUSIONS: Our results document that the response of elderly adults to the third dose of the vaccine was delayed, but still able to achieve comparable immune effects compared to younger adults, in regard to antibody responses as well as at the transcript level.

Ferroptosis: action and mechanism of chemical/drug-induced liver injury.

Drug-induced liver injury (DILI) is characterized by hepatocyte injury, cholestasis injury, and mixed injury. The liver transplantation is required for serious clinical outcomes such as acute liver failure. Current studies have found that many mechanisms were involved in DILI, such as mitochondrial oxidative stress, apoptosis, necroptosis, autophagy, ferroptosis, etc. Ferroptosis occurs when hepatocytes die from iron-dependent lipid peroxidation and plays a key role in DILI. After entry into the liver, where some drugs or chemicals are metabolized, they convert into hepatotoxic substances, consume reduced glutathione (GSH), and decrease the reductive capacity of GSH-dependent GPX4, leading to redox imbalance in hepatocytes and increase of reactive oxygen species (ROS) and lipid peroxidation level, leading to the undermining of hepatocytes; some drugs facilitated the autophagy of ferritin, orchestrating the increased ion level and ferroptosis. The purpose of this review is to summarize the role of ferroptosis in chemical- or drug-induced liver injury (chemical/DILI) and how natural products inhibit ferroptosis to prevent chemical/DILI.

A variant of the venom allergen-like protein, DdVAP2, is required for the migratory endoparasitic plant nematode Ditylenchus destructor parasitism of plants.

The potato rot nematode, Ditylenchus destructor, poses a serious threat to numerous root and tuber crops, yet the functional characterization of effectors from this migratory endoparasitic plant nematode remains limited. Despite inhabiting distinct habitats, sedentary and migratory plant parasitic nematodes share the structurally conserved effectors, such as venom allergen-like proteins (VAPs). In this study, a variant of DdVAP2 was cloned from D. destructor. The transcription profile analysis revealed that DdVAP2 was higher expressed in D. destructor feeding on either potato or sweet potato compared to on fungus via qRT-PCR. And DdVAP2 was highly expressed at all life stages feeding on sweet potato, except for eggs. DdVAP2 was confirmed to be specifically expressed in the subventral esophageal glands of D. destructor through in situ hybridization assays. Combined with functional validation of the signal peptide of DdVAP2, it suggested that DdVAP2 could be secreted from nematode into host. Heterologous expression of DdVAP2 in Nicotiana benthamiana revealed that the protein localized in both cytosol and nuclei of plant cells. Knocking down DdVAP2 by RNAi in D. destructor resulted in infection and reproduction defects on plants. All the results suggest that DdVAP2 plays a crucial role in the interaction between D. destructor and plants by facilitating the nematode infection.

Guiding the postoperative radioactive iodine-131 therapy for patients with papillary thyroid carcinoma according to the prognostic risk groups: a SEER-based study.

PURPOSE: The effectiveness of iodine-131(131I) therapy in patients with papillary thyroid cancer (PTC) of various stage is controversial. This study aimed to use prognostic risk groups to guide 131I therapy in patients with PTC after radical thyroidectomy. METHODS: Data of 53,484 patients with PTC after radical thyroidectomy were collected from the Epidemiology and End Results (SEER) database. Patients were divided into subgroups according to MACIS system and regional lymph node involvement. The prognostic role of 131I therapy was investigated by comparing Kaplan-Meier survival analysis and Cox proportional hazard models in different subgroups. RESULTS: Sex, age, tumor size, invasion, regional lymph node involvement, and distant metastasis was related to the survival of patients with PTC. If MACIS < 7, 131I treatment didn't affect the cancer-specific survival (CSS) rate. If MACIS ≥ 7, 131I therapy didn't work on CSS rate for patients with N0 or N1a < 5 status; 131I therapy had improved CSS rate for patients in the N1a ≥ 5 or N1b status. If patients with distant metastasis, invasion, or large tumor, 131I therapy didn't improve CSS rate for patients in N0 or N1a < 5 stage. CONCLUSION: After radical thyroidectomy, if MACIS < 7, patients with PTC could avoid 131I therapy. If MACIS ≥ 7, patients in the N0 or N1a < 5 could avoid 131I therapy; those in the N1a ≥ 5 or N1b stage should be given 131I therapy. Among them, all patients with distant metastasis should be given 131I therapy.

Single cell in vivo optogenetic stimulation by two-photon excitation fluorescence transfer.

Optogenetic manipulation with single-cell resolution can be achieved by two-photon excitation. However, this frequently requires relatively high laser powers. Here, we developed a novel strategy that can improve the efficiency of current two-photon stimulation technologies by positioning fluorescent proteins or small fluorescent molecules with high two-photon cross-sections in the vicinity of opsins. This generates a highly localized source of endogenous single-photon illumination that can be tailored to match the optimal opsin absorbance. Through neuronal and vascular stimulation in the live mouse brain, we demonstrate the utility of this technique to achieve efficient opsin stimulation, without loss of cellular resolution. We also provide a theoretical framework for understanding the potential advantages and constrains of this methodology, with directions for future improvements. Altogether, this fluorescence transfer illumination method opens new possibilities for experiments difficult to implement in the live brain such as all-optical neural interrogation and control of regional cerebral blood flow.

Dynamic Stiffening Hydrogel with Instructive Stiffening Timing Modulates Stem Cell Fate In Vitro and Enhances Bone Remodeling In Vivo.

Biomechanical stimuli derived from the extracellular matrix (ECM) extremely tune stem cell fate through 3D and spatiotemporal changes in vivo. The matrix stiffness is a crucial factor during bone tissue development. However, most in vitro models to study the osteogenesis of mesenchymal stem cells (MSCs) are static or stiffening in a 2D environment. Here, a dynamic and controllable stiffening 3D biomimetic model is created to regulate the osteogenic differentiation of MSCs with a dual-functional gelatin macromer that can generate a double-network hydrogel by sequential enzymatic and light-triggered crosslinking reactions. The findings show that these dynamic hydrogels allowed cells to spread and expand prior to the secondary crosslinking and to sense high stiffness after stiffening. The MSCs in the dynamic hydrogels, especially the hydrogel stiffened at the late period, present significantly elevated osteogenic ECM secretion, gene expression, and nuclear localization of Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ). In vivo evaluation of animal experiments further indicates that the enhancement of dynamic stiffening on osteogenesis of MSCs substantially promotes bone remodeling. Consequently, this work reveals that the 3D dynamic stiffening microenvironment as a critical biophysical cue not only mediates the stem cell fate in vitro, but also augments bone restoration in vivo.

Retinal degeneration in rpgra mutant zebrafish.

Introduction: Pathogenic mutations in RPGR ORF15, one of two major human RPGR isoforms, were responsible for most X-linked retinitis pigmentosa cases. Previous studies have shown that RPGR plays a critical role in ciliary protein transport. However, the precise mechanisms of disease triggered by RPGR ORF15 mutations have yet to be clearly defined. There are two homologous genes in zebrafish, rpgra and rpgrb. Zebrafish rpgra has a single transcript homologous to human RPGR ORF15; rpgrb has two major transcripts: rpgrb ex1-17 and rpgrb ORF15, similar to human RPGR ex1-19 and RPGR ORF15, respectively. rpgrb knockdown in zebrafish resulted in both abnormal development and increased cell death in the dysplastic retina. However, the impact of knocking down rpgra in zebrafish remains undetermined. Here, we constructed a rpgra mutant zebrafish model to investigate the retina defect and related molecular mechanism. Methods: we utilized transcription activator-like effector nuclease (TALEN) to generate a rpgra mutant zebrafish. Western blot was used to determine protein expression. RT-PCR was used to quantify gene transcription levels. The visual function of embryonic zebrafish was detected by electroretinography. Immunohistochemistry was used to observe the pathological changes in the retina of mutant zebrafish and transmission electron microscope was employed to view subcellular structure of photoreceptor cells. Results: A homozygous rpgra mutant zebrafish with c.1675_1678delins21 mutation was successfully constructed. Despite the normal morphological development of the retina at 5 days post-fertilization, visual dysfunction was observed in the mutant zebrafish. Further histological and immunofluorescence assays indicated that rpgra mutant zebrafish retina photoreceptors progressively began to degenerate at 3-6 months. Additionally, the mislocalization of cone outer segment proteins (Opn1lw and Gnb3) and the accumulation of vacuole-like structures around the connecting cilium below the OSs were observed in mutant zebrafish. Furthermore, Rab8a, a key regulator of opsin-carrier vesicle trafficking, exhibited decreased expression and evident mislocalization in mutant zebrafish. Discussion: This study generated a novel rpgra mutant zebrafish model, which showed retinal degeneration. our data suggested Rpgra is necessary for the ciliary transport of cone-associated proteins, and further investigation is required to determine its function in rods. The rpgra mutant zebrafish constructed in this study may help us gain a better understanding of the molecular mechanism of retinal degeneration caused by RPGR ORF15 mutation and find some useful treatment in the future.

Framing of female medical personnel during the COVID-19 pandemic: a case study of the Chinese official media.

This paper analyzes the media frames adopted by the official WeChat and Sina Weibo accounts of the People's Daily between January 1 and December 31, 2020, for reports about female medical personnel involved in pandemic prevention and control. Although the number of female medical personnel involved in pandemic prevention and control far exceeded that of their male counterparts, the extent of media reports on the former was far less than that of the latter. The human interest frame about female medical personnel was mainly applied, while the use of the action frame was less frequent, which highlighted the gender identity and family role of these women but weakened their professional identity. This was not conducive to praising the contributions of female medical personnel in fighting the pandemic. The media frames of reporting medical personnel in WeChat and Sina Weibo accounts of the People's Daily are not always the same. After Wuhan's lockdown ended on April 8, the proportion of the human interest frame of the report text of female medical personnel decreased, and the proportion of the action frame increased, while the proportion of the human interest frame of the report text of male medical personnel increased and the proportion of the action frame decreased. Previous studies mainly analyzed the use of the media frames of female news personalities, but few studies focused on whether women had the possibility of breaking away from the gender media frames. This study shows that some female medical personnel with exceptional professional competence are likely to transcend the gender media frames and receive similar coverage to that of male medical professionals, like Li Lanjuan and Chen Wei.

TRIM55 inhibits colorectal cancer development via enhancing protein degradation of c-Myc.

BACKGROUND: Colorectal cancer (CRC) is one of the most common and lethal malignancies which including colon and rectum cancer. Tripartite motif containing 55 (TRIM55) is an E3 ubiquitin ligase belonging to the TRIM family. Although the aberrant TRIM55 expression has been implicated in several tumors, its functional role, and molecular mechanisms in CRC remain unknown. METHODS: Immunohistochemical studies, qRT-PCR, and Western blot were performed to analyze the expression of TRIM55 in CRC patients and cell lines. TRIM55 expression and its relevance to clinical traits and prognosis were further explored in the TCGA database, and in our 87 clinical samples. Subsequently, we performed a series of functional assays to explore the effect of TRIM55 on CRC progression. Finally, the molecular mechanism of TRIM55 was investigated by immunoprecipitation and ubiquitination analyses. RESULTS: Here, we demonstrated that TRIM55 was markedly downregulated in CRC cell lines and tumors from CRC patients. Moreover, overexpression of TRIM55 could suppress CRC cell growth in vitro and inhibit CRC xenograft tumor development in vivo. Additionally, TRIM55 overexpression dampened CRC cell migration and invasion. Further bioinformatics analysis indicated that TRIM55 suppressed cyclin D1 and c-Myc expression. Mechanistically, co-immunoprecipitation assay revealed that TRIM55 directly interacted with c-Myc and down-regulated its protein expression level via protein ubiquitination. Intriguingly, c-Myc overexpression partially antagonized the function of TRIM55 overexpression. CONCLUSIONS: Taken together, our findings suggest that TRIM55 inhibits CRC tumor development via, at least in part, enhancing protein degradation of c-Myc. Targeting TRIM55 could provide a new therapeutic approach for CRC patients.

Epidemiological investigation and drug resistance characteristics of Riemerella anatipestifer strains from large-scale duck farms in Shandong Province, China from March 2020 to March 2022.

Infectious serositis is a common disease caused by Riemerella anatipestifer (R. anatipestifer) in ducks, characterized by respiratory distress, septicemia, and neurological symptoms. In this study, 1,020 samples (brain and liver) were collected from ducks with suspected R. anatipestifer infection from March 2020 to March 2022 in Shandong Province, of which 171 R. anatipestifer strains were identified by PCR and isolation culture. The serotype of all strains was analyzed, and 74 strains were subjected to drug sensitivity tests and drug resistance genes detection. The results showed that the overall prevalence rate of R. anatipestifer in Shandong Province was 16.7% (171/1,020), with most strains coming from brain samples of ducklings under 3-mo old collected from September to December each year. Histopathological examination showed that heart vessels of the diseased duck were highly dilated and filled with red blood cells, with obvious fibrin exudates outside the pericardium, and fatty degeneration of liver cells. There were 45 strains of serotype 1, 45 strains of serotype 2, 2 strains of serotype 4, 33 strains of serotype 6, 44 strains of serotype 7, and 2 strains of serotype 10. The minimum inhibitory concentration (MIC) of 10 common antibiotics against 74 representative strains was determined by the agar dilution method. It was found that 74 strains had the most severe resistance to gentamicin (77%) and fully susceptible to ceftriaxone, but the 81.1% isolated strains were multidrug resistant. Resistance genes testing of 74 R. anatipestifers showed that tetracycline resistance gene tet X had the highest detection rate of 95.9%, followed by macrolide resistance gene ermF with 77%, and the rate of ß-lactam resistance gene blaTEM is the lowest (10.8%). The animal experiment of 4 R. anatipestifer strains with different serotypes showed that they had strong pathogenicity to 7-day-old ducklings, which could cause nervous symptoms, and the mortality rate was 58% to 70%. The autopsy showed obvious pathological changes. These findings of this study on R. anatipestifer will help us to understand the latest prevalence, drug resistance characteristics, and pathogenicity of R. anatipestifer in Shandong, China, and provide a scientific guide for the treatment and control of the disease.

Controlled Synthesis, Chiral Assembly, and Circularly Polarized Luminescence of Poly(Phenyl Isocyanide)-Block-Polyfluorene Copolymers.

In this work, π-conjugated block copolymers consisting of poly(phenyl isocyanide) (PPI) and polyfluorene (PF) segments are facilely prepared by one-pot sequential polymerization of phenyl isocyanide (monomer 1) and 7-bromo-9,9-dioctylfluorene-2-boronic acid pinacol ester (monomer 2). The Pd(II)-terminated PPI is first prepared via polymerizing monomer 1 catalyzed with phenyl alkyne-Pd(II) complex and then utilized to initiate the controlled Suzuki cross-coupling polymerization of monomer 2, yielding various PPI-b-PF copolymers possessing controlled molar mass and narrow dispersity. Owing to the helical conformation of PPI segment and π-conjugated structure of PF segment, PPI-b-PF copolymers present distinctive optical property and fascinating chiral self-assembly behavior. During the self-assembly process, chirality transfer from helical PPI block to the supramolecular aggregates of helical nanofibers occurs to afford optically active helical nanofibers with high optical activity. Furthermore, the self-assembled helical nanofibers exhibit excellent circularly polarized luminescence performance.

Mixed Rare-Earth Chalcogenide Borate Eu9-xRExMgS2B20O41 (RE = Sm, Gd) Featuring a 3D {[B20O41]22-}∞ Framework Connected by [B6O9(O0.5)6]6- and [B7O13(O0.5)3]8- Clusters.

Rare-earth (RE) chalcogenide borates are very rarely discovered in view of the difficulties in synthesis though they have demonstrated attractive physical performances. Here, the first mixed RE chalcogenide borates Eu5.4Sm3.6MgS2B20O41 (1) and Eu3Gd6MgS2B20O41 (2) are synthesized by combining RE, sulfur, and borate ions into one structure. They crystallize in the centrosymmetric hexagonal space group P63/m, and their 3D honeycomb-like {[B20O41]22-}∞ open frameworks are built by [B6O9(O0.5)6]6- and [B7O13(O0.5)3]8- polyanionic clusters and consolidated by Mg2+ ions; both of which are formed by BO4 tetrahedra and BO3 planar triangles. The coordination modes of RE ions are rare REO6S2 bicapped trigonal prisms and REO8S irregular polyhedra, and their band gaps are determined to be 2.25 and 2.22 eV, respectively. They exhibit antiferromagnetic interactions and distinct photocurrent responses. The corresponding theoretical calculations are also performed. The study of 1 and 2 perhaps stimulates interest in exploring new functional RE chalcogenide borates.