Biofortifying multiple micronutrients and decreasing arsenic accumulation in rice grain simultaneously by expressing a mutant allele of OAS-TL gene.

Rice grains typically contain relatively high levels of toxic arsenic (As) but low levels of essential micronutrients. Biofortification of essential micronutrients while decreasing As accumulation in rice would benefit human nutrition and health. We generated transgenic rice expressing a gain-of-function mutant allele astol1 driven by the OsGPX1 promoter. astol1 encodes a plastid-localized O-acetylserine (thiol) lyase (OAS-TL) with Ser189Asn substitution (OsASTOL1S189N), which enhances cysteine biosynthesis by forming an indissociable cysteine synthase complex with its partner serine acetyltransferase (SAT). The effects on growth, As tolerance, and nutrient and As accumulation in rice grain were evaluated in hydroponic, pot and field experiments. The expression of OsASTOL1S189N in pOsGPX1::astol1 transgenic lines enhanced SAT activity, sulphate uptake, biosynthesis of cysteine, glutathione, phytochelatins and nicotianamine, and enhanced tolerance to As. The expression of OsASTOL1S189N decreased As accumulation while increased the accumulation of multiple macronutrients (especially sulphur, nitrogen and potassium) and micronutrients (especially zinc and selenium) in rice grain in a pot experiment and two field experiments, and had little effect on plant growth and grain yield. Our study provides a new strategy to genetically engineer rice to biofortify multiple essential nutrients, reducing As accumulation in rice grain and enhancing As tolerance simultaneously.

Genetic complexity of killer-cell immunoglobulin-like receptor genes in human pangenome assemblies.

The killer-cell immunoglobulin-like receptor (KIR) gene complex, a highly polymorphic region of the human genome that encodes proteins involved in immune responses, poses strong challenges in genotyping owing to its remarkable genetic diversity and structural intricacy. Accurate analysis of KIR alleles, including their structural variations, is crucial for understanding their roles in various immune responses. Leveraging the high-quality genome assemblies from the Human Pangenome Reference Consortium (HPRC), we present a novel bioinformatic tool, the structural KIR annoTator (SKIRT), to investigate gene diversity and facilitate precise KIR allele analysis. In 47 HPRC-phased assemblies, SKIRT identifies a recurrent novel KIR2DS4/3DL1 fusion gene in the paternal haplotype of HG02630 and maternal haplotype of NA19240. Additionally, SKIRT accurately identifies eight structural variants and 15 novel nonsynonymous alleles, all of which are independently validated using short-read data or quantitative polymerase chain reaction. Our study has discovered a total of 570 novel alleles, among which eight haplotypes harbor at least one KIR gene duplication, six haplotypes have lost at least one framework gene, and 75 out of 94 haplotypes (79.8%) carry at least five novel alleles, thus confirming KIR genetic diversity. These findings are pivotal in providing insights into KIR gene diversity and serve as a solid foundation for understanding the functional consequences of KIR structural variations. High-resolution genome assemblies offer unprecedented opportunities to explore polymorphic regions that are challenging to investigate using short-read sequencing methods. The SKIRT pipeline emerges as a highly efficient tool, enabling the comprehensive detection of the complete spectrum of KIR alleles within human genome assemblies.

A retrospective study on the outcome of pulpotomy with iRoot BP plus in primary molars and its relationship with hemostasis time.

BACKGROUND: Pulpotomy is a crucial method to preserve primary teeth until natural exfoliation. This study aimed to evaluate the clinical and radiographic outcomes of pulpotomy with iRoot BP Plus in primary molars and to explore the association between hemostasis time and these outcomes. METHODS: Primary molars that underwent iRoot BP Plus pulpotomy and were followed for at least 12 months were selected for this study. Clinical and radiographic data were collected, and the success rate was analyzed in relation to factors such as hemostasis time, tooth type, and arch type. The tests of significance used were the chi-square test, Fisher's exact test, or Kruskal-Wallis test. Statistical significance was set at P < 0.05. RESULTS: A total of 183 teeth in 106 patients were included in the analysis. The follow-up period fell into a range of 1-3 years, with a mean of 1.6 years. The clinical and radiographic success rates were 96.7% and 92.9%, respectively. The earliest time to observe the radiographic failures was half a year after the treatment, and the latest time was two years after the treatment. Among all the teeth, 130 were recorded with hemostasis time before the application of iRoot BP Plus. Compared to teeth with a hemostasis time of 5 min or less, teeth with a hemostasis time exceeding 5 min showed no significant differences in clinical and radiographic success (P = 1.000 and 0.879). Additionally, neither arch nor teeth type showed a relationship with the pulpotomy success rate (P > 0.05). CONCLUSIONS: Pulpotomy using iRoot BP Plus in primary molars achieved favorable results. The hemostasis time may not significantly impact the outcomes of pulpotomy using iRoot BP Plus in primary molars.

Single-cell analysis of peri-implant gingival tissue to assess implant biocompatibility and immune response.

PURPOSE: The innate immune response, particularly the reaction of polymorphonuclear neutrophils (PMNs), is crucial in shaping the outcomes of chronic inflammation, fibrosis, or osseointegration following biomaterial implantation. Peri-implantitis or peri-mucositis, inflammatory conditions linked to dental implants, pose a significant threat to implant success. We developed a single-cell analysis approach using a murine model to assess the immune response to implant materials, offering a practical screening tool for potential dental implants. METHODS: We performed bioinformatics analysis and established a peri-implant inflammation model by inserting two titanium implants into the maxillary region, to examine the immune response. RESULTS: Bioinformatics analysis revealed that titanium implants triggered a host immune response, primarily mediated by PMNs. In the in vivo experiments, we observed a rapid PMN-mediated response, with increased infiltration around the implants and on the implant surface by day 3. Remarkably, PMN attachment to the implants persisted for 7 days, resembling the immune profiles seen in human implant-mediated inflammation. CONCLUSIONS: Our findings indicate that persistent attachment of the short-living PMNs to titanium implants can serve as an indicator or traits of peri-implant inflammation. Therefore, analyzing gingival tissue at the single-cell level could be a useful tool for evaluating the biocompatibility of candidate dental implants.

Outcome of regenerative endodontic procedures in delayed replanted immature permanent teeth with apical periodontitis: A retrospective study.

BACKGROUND: Regenerative endodontic procedures (REPs) is effective for treating young permanent teeth with pulp necrosis. However, its efficacy on delayed replanted avulsed teeth is unclear. AIM: This retrospective study aimed to assess the efficacy of REPs in treating delayed replanted immature permanent teeth with apical periodontitis. DESIGN: Avulsed teeth receiving REPs were systematically screened based on predetermined criteria. This study assessed the REP outcomes, postoperative periodontal healing, and overall treatment efficacy. Samples were grouped by REP outcomes and root development stage, with Fisher's exact tests used to compare outcomes among different groups. RESULTS: Among the included 17 teeth, 47.1% exhibited successful REPs and periodontal healing. Another 47.1%, due to replacement resorption or REP failure, were categorized as tooth survival. Healing of periapical lesions was observed in 88.2% of the cases, but only 41.2% demonstrated continued root development. Although differences were not significant (p = 0.05), teeth with continued root development had a higher rate of functional healing (85.7%) compared to those without (30%). CONCLUSION: Within the limitations of this study, REPs presented reliable outcomes for treating delayed replanted immature permanent teeth with apical periodontitis mainly in periapical lesion healing. Teeth with continued root development after REPs exhibited a higher rate of functional healing. Further investigation is required to explore potential synergies between REP outcomes and periodontal healing.

Toll-Like Receptor 2 Deficiency Exacerbates Dextran Sodium Sulfate-Induced Intestinal Injury through Marinifilaceae-Dependent Attenuation of Cell Cycle Signaling.

BACKGROUND: Ulcerative colitis (UC) is an intestinal disorder marked by chronic, recurring inflammation, yet its underlying mechanisms have not been fully elucidated. METHODS: The current research dealt with examining the biological impacts of toll-like receptor 2 (TLR2) on dextran sulfate sodium (DSS)-triggered inflammation in the intestines of wild-type (WT) and TLR2-knockout (TLR2-KO) colitis mouse models. To elucidate the protective function of TLR2 in DSS-triggered colitis, RNA-sequencing (RNA-Seq) was carried out to compare the global gene expression data in the gut of WT and TLR2-KO mice. Further, 16S rRNA gene sequencing revealed notable variations in gut microbiota composition between WT and TLR2-KO colitis mice. RESULTS: It was revealed that TLR2-KO mice exhibited increased susceptibility to DSS-triggered colitis. RNA-Seq results demonstrated that cell cycle pathway-related genes were notably downregulated in TLR2-KO colitis mice (enrichment score = 30, p < 0.001). 16S rRNA gene sequencing revealed that in comparison to the WT colitis mice, the relative abundance of Marinifilacea (p = 0.006), Rikenellacea (p = 0.005), Desulfovibrionaceae (p = 0.045), Tannerellaceae (p = 0.038), Ruminococcaceae (p = 0.003), Clostridia (p = 0.027), and Mycoplasmataceae (p = 0.0009) was significantly increased at the family level in the gut of TLR2-KO colitis mice. In addition, microbiome diversity-transcriptome collaboration analysis highlighted that the relative abundance of Marinifilaceae was negatively linked to the expression of cell cycle signaling-related genes (p values were all less than 0.001). CONCLUSION: Based on these findings, we concluded that TLR2-KO exacerbates DSS-triggered intestinal injury by mitigating cell cycle signaling in a Marinifilaceae-dependent manner.

Corrigendum: Risk of primary Sjogren's Syndrome following human papillomavirus infections: a nationwide population-based cohort study.

[This corrects the article DOI: 10.3389/fimmu.2022.967040.].

Evaluation of dupilumab on the disease burden in children and adolescents with atopic dermatitis: A population-based cohort study.

BACKGROUND: Dupilumab is the first and only biologic agent approved for the treatment of atopic dermatitis (AD) in pediatric patients aged from 6 months to 17 years. The study aimed to evaluate the impact of dupilumab on the occurrence of comorbidities in pediatric patients with AD. METHODS: In this population-based cohort study, we utilized electronic health records from multiple healthcare organizations across the United States. Pediatric patients (<18 years of age) with a diagnosis of AD initiating dupilumab were propensity-score matched 1:1 to those initiating other systemic agents (azathioprine, cyclosporine, methotrexate, mycophenolate mofetil, or systemic corticosteroids). The primary outcomes were new-onset comorbidities emerging during the study period measured by the risk ratio (RR) and its confidence interval (CI). Subgroup analyses were stratified by age (0-5 years, 6-11 years, and 12-17 years), sex, and race. RESULTS: A total of 3575 pediatric patients with AD treated with dupilumab were matched to 3575 patients treated with other systemic agents. The dupilumab cohort was associated with a lowered risk of new-onset atopic comorbidities (including asthma [RR, 0.72; 95% CI, 0.59-0.89] and allergic rhinitis [RR, 0.62; 95% CI, 0.52-0.74]), infections (e.g., skin and soft tissue infection [RR, 0.70; 95% CI, 0.63-0.76] and respiratory tract infection [RR = 0.56; 95% CI, 0.51-0.61]), psychiatric disorders (e.g., mood disorder [RR, 0.52; 95% CI, 0.39-0.70] and anxiety [RR, 0.57; 95% CI, 0.46-0.70], sleep disturbance [RR, 0.60; 95% CI, 0.47-0.77]), neurologic and developmental disorders (e.g., attention deficit hyperactivity disorder [RR, 0.54; 95% CI, 0.38-0.75]). Furthermore, the positive effects are found to be more pronounced in younger children (aged 0-5 years) with AD. CONCLUSIONS: Treatment with dupilumab compared to systemic agents resulted in reductions in AD-related comorbidities in pediatric patients.

Radiomics of intrathrombus and perithrombus regions for Post-EVT intracranial hemorrhage risk Prediction: A multicenter CT study.

OBJECTIVES: This study aimed to assess the predictive performance of radiomics derived from computed tomography (CT) images of thrombus regions in predicting the risk of intracranial hemorrhage (ICH) following endovascular thrombectomy (EVT). MATERIALS AND METHODS: This retrospective multicenter study included 336 patients who underwent admission CT and EVT for acute anterior-circulation large vessel occlusion between December 2018 and December 2023. Follow-up imaging was performed 24 h post-procedure to evaluate the occurrence of ICH. 230 patients from centers A and B were randomly allocated into training and test groups in a 7:3 ratio, while the remaining 106 patients from center C comprised the validation cohort. Radiologists manually segmenting the thrombus on CT images, and the perithrombus region was defined by expanding the initial region of interest (ROI). A total of 428 radiomics features were extracted from both intrathrombus and perithrombus regions on CT images. The Mann-Whitney U test was used for feature selection, and least absolute shrinkage and selection operator (LASSO) regression was employed for model development, followed by validation using a 5-fold cross-validation approach. Model performance was assessed using the area under the curve (AUC) of the receiver operating characteristic (ROC). RESULTS: Among the eligible patients, 128 (38.1 %) experienced ICH after EVT. The combined model exhibited superior performance in the training cohort (AUC: 0.913, 95 % CI: 0.861-0.965), test cohort (AUC: 0.868, 95 % CI: 0.775-0.962), and validation cohort (AUC: 0.850, 95 % CI: 0.768-0.912). Notably, in the validation group, both the perithrombus and combined models demonstrated higher predictive accuracy compared to the intrathrombus model (0.837 vs. 0.684, p = 0.02; AUC: 0.850 vs. 0.684, p = 0.01). CONCLUSIONS: Radiomics features derived from the perithrombus region significantly enhance the prediction of ICH after EVT, providing valuable insights for optimizing post-procedural clinical decisions. CLINICAL RELEVANCE STATEMENT: This study highlights the importance of radiomics extracted from intrathrombus and perithrombus region in predicting intracranial hemorrhagefollowing endovascular thrombectomy, which can aid in improving patient outcomes.

Application of the second-generation sequencing technology of metagenomics in the detection of pathogens in respiratory patients.

OBJECTIVE: To explore the application value of the second-generation metagenomic next-generation sequencing (mNGS) in the detection of pathogens in patients with pulmonary infection. METHODS: We conducted a retrospective analysis of 65 pulmonary infection cases treated at our institution and the Fifth People's Hospital of Shanghai between January 2021 and May 2023. All subjects were subjected to mNGS, targeted next-generation sequencing (tNGS), and conventional microbiological culture. A comparative analysis was performed to evaluate the diversity and quantity of pathogens identified by these methodologies and to appraise their respective diagnostic capabilities in pulmonary infection diagnostics. RESULTS: The mNGS successfully identified etiological agents in 60 of the 65 cases, compared to tNGS, which yielded positive results in 42 cases, and conventional laboratory cultures, which detected pathogens in 24 cases. At the bacterial genus level, mNGS discerned 9 genera, 11 species, and 92 isolates of pathogenic bacteria, whereas tNGS identified 8 genera, 8 species, and 71 isolates. Conventional methods were less sensitive, detecting only 6 genera, 7 species, and 33 isolates. In terms of fungal detection, mNGS identified 4 fungal species, tNGS detected 4 isolates of the Candida genus, and conventional methods identified 2 isolates of the same genus. Viral detection at the species level revealed 10 species and 46 isolates by mNGS, whereas tNGS detected only 3 species and 7 isolates. The area under the receiver operating characteristic curve (AUC) with 95% confidence intervals for diagnosing pulmonary infections was 0.818 (0.671 to 0.966) for mNGS, 0.668 (0.475 to 0.860) for tNGS, and 0.721 (0.545 to 0.897) for conventional culture.The mNGS demonstrates superior diagnostic efficacy and pathogen detection breadth in critically ill patients with respiratory infections, offering a significant advantage by reducing the time to diagnosis. The enhanced sensitivity and comprehensive pathogen profiling of mNGS underscore its potential as a leading diagnostic tool in clinical microbiology.

Comparative safety of oral Janus kinase inhibitors versus dupilumab in patients with atopic dermatitis: A population-based cohort study.

BACKGROUND: Systemic Janus kinase inhibitors (JAKi) and dupilumab both have emerged as promising therapeutics for atopic dermatitis (AD). Dupilumab has a favorable safety profile, but oral JAKi therapy has been established in other diseases that carry potential comorbid susceptibilities that influence safety. OBJECTIVE: We sought to provide real-world evidence of the comparative safety of oral JAKi versus dupilumab in patients with AD. METHODS: The study used observational data from multiple healthcare organizations in the US. Patients with AD treated with either oral JAKi (upadacitinib, abrocitinib, and baricitinib) or dupilumab were enrolled. The 2 treatment groups were propensity score matched 1:1 on the basis of demographics, comorbidities, and prior medications. Safety outcomes within 2 years after the initiation of medications were measured by hazard ratios (HRs) with 95% confidence intervals (CIs). RESULTS: A total of 14,716 patients were included, with 942 patients treated with oral JAKi and 13,774 with dupilumab. The 2 treatment groups respectively included 938 patients after matching. Treatment with oral JAKi was not associated with increased risks of mortality, malignancies, major adverse cardiovascular events, venous thromboembolism, renal events, or serious gastrointestinal events. However, patients receiving oral JAKi showed significantly higher risks of skin and subcutaneous tissue infection (HR = 1.35, 95% CI = 1.07-1.69), herpes infection (herpes simplex, HR = 1.64, 95% CI = 1.03-2.61; herpes zoster, HR = 2.51, 95% CI = 1.14-5.52), acne (HR = 2.09, 95% CI = 1.54-2.84), cytopenia (anemia, HR = 1.83, 95% CI = 1.39-2.41; neutropenia, HR = 4.02, 95% CI = 1.91-8.47; thrombocytopenia, HR = 1.76, 95% CI = 1.08-2.89), and hyperlipidemia (HR = 1.45, 95% CI = 1.09-1.92); the risk of ophthalmic complications was higher in those receiving dupilumab (HR = 1.49, 95% CI = 1.03-2.17). CONCLUSION: Oral JAKi did not exhibit concerning safety issues in treating patients with AD but increased the risk of infections and abnormalities in laboratory findings. Long-term follow-up data are required to validate these results.

The causal relationship between gut microbiota and constipation: a two-sample Mendelian randomization study.

BACKGROUND: Constipation is one of the most common gastrointestinal disorders afflicting the population, with recent observational studies implicating dysfunction of the gut microbiota in constipation. Despite observational studies indicating a relationship, a clear causality remains unclear. This study aims to use two-sample Mendelian randomization (MR) to establish a clearer causal relationship between the two. METHODS: A two-sample Mendelian randomization (MR) study was performed using the gut microbiota summary Genome-Wide Association Studies (GWAS) statistics from MiBioGen consortium (n = 13,266) and constipation GWAS summary statistics from the IEU OpenGWAS database. The causality between gut microbiota and constipation is primarily analyzed using the inverse-variance weighted (IVW) method and reinforced by an additional four methods, including MR-Egger, Weighted Median, Simple Mode, and Weighted Mode. Finally, funnel plot, heterogeneity test, horizontal pleiotropy test, and leave-one-out test were used to evaluate the reliability of MR results. RESULTS: IVW estimates suggested that the bacterial species Anaerotruncus, Butyricimonas, and Hungatella were causally associated with constipation. The odds ratio (OR) values of Anaerotruncus, Butyricimonas, and Hungatella were 1.08 (95% CI = 1.02-1.13; P = 0.007), 1.07 (95% CI = 1.01-1.13; P = 0.015), 1.03 (95% CI = 1.00-1.06; P = 0.037) respectively. Meanwhile, Ruminiclostridium 9 and Intestinibacter have been shown to be associated with a reduced risk of constipation. The OR of Ruminiclostridium 9 = 0.75(95% CI = 0.73-0.78, P < 0.001 and Intestinibacter of OR = 0.89 (95% CI = 0.86-0.93, P < 0.001). Furthermore, validation by funnel plot, heterogeneity test, and horizontal pleiotropy test showed that MR results were reliable. CONCLUSION: This is the first Mendelian randomization study to explore the causalities between specific gut microbiota taxa and constipation, and as such may be useful in providing insights into the unclear pathology of constipation which can in turn aid in the search for prevention and treatment.

Endometriosis and Sjögren's syndrome: Bidirectional associations in population-based 15-year retrospective cohorts.

INTRODUCTION: Primary Sjögren's syndrome (pSS) is a chronic autoimmune disorder affecting salivary and lacrimal glands, while endometriosis involves uterine-like tissue growth outside the uterus, causing pelvic pain and infertility. Investigating their intricate relationship using real-world data is crucial due to limited research on their connection. MATERIAL AND METHODS: This population-based cohort study included patients with endometriosis and controls without endometriosis. Propensity score matching was used to balance baseline differences in demographic and clinic characteristics between the two groups. Cox proportional hazards model were used to estimate the effect of endometriosis on the risk of new-onset pSS over time. A symmetrical cohort study, including patients with pSS and propensity score-matched controls without pSS, was conducted to investigate the effect of pSS on the risk of endometriosis over time. To elaborate on the mechanisms linking endometriosis and pSS, Ingenuity Pathway Analysis was performed to identify activated pathways in eutopic endometrium from patients with endometriosis and parotid tissues from patients with pSS. RESULTS: A total of 15 947 patients with endometriosis and 15 947 propensity score-matched controls without endometriosis were included. Patients with endometriosis presented a significantly greater risk of pSS compared to non-endometriosis controls (adjusted hazard ratio, aHR = 1.57, 95% CI = 1.29-1.91, p < 0.001). In the symmetrical cohort study, which included 4906 pSS patients and 4,906 propensity score-matched controls without pSS, patients with pSS were found to be at a significantly higher risk of endometriosis compared to non-pSS controls (aHR = 1.51, 95% CI = 1.12-2.04, p = 0.012). Ingenuity Pathway Analysis showed that the underlying cellular mechanisms involved autoimmune-related pathways, including activation of dendritic cell maturation, and chronic inflammatory pathways, including the fibrosis signaling pathway. CONCLUSIONS: These findings support a bidirectional association between endometriosis and pSS, which may be driven by dendritic cell maturation and fibrosis signaling pathways.

Periodontitis is an immune-related adverse event associated with immune checkpoint inhibitors: A multi-center cohort study.

Immune checkpoint inhibitors (ICIs) cause immune-related adverse events (irAEs) across various organ systems including oral health complications such as dry mouth and stomatitis. In this study, we aimed to determine the risk of periodontitis among patients on immune checkpoint inhibitors (ICIs) and to test the associations between ICI-associated periodontitis and other immune-related adverse events (irAEs). We performed a retrospective cohort study involving adult cancer patients between January 2010 and November 2021. Patients on an ICI were propensity score-matched to patients not on an ICI. The primary outcome was the occurrence of periodontitis. ICIs included programmed cell death 1 (PD-1) inhibitors programmed cell death ligand 1 (PD-L1) inhibitors, and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibitors. The risk of periodontitis following ICI use was derived through a Cox proportional hazard model and Kaplan-Meier survival analysis. Overall, 868 patients on an ICI were matched to patients not on an ICI. Among the ICI cohort, 41 (4.7 %) patients developed periodontitis. The incidence rate of periodontitis was significantly higher in patients on an ICI than in patients not on an ICI (55.3 vs 25.8 per 100 patient-years, incidence rate ratio = 2.14, 95 % CI = 1.38-3.33). Both the use of PD-L1 inhibitors (multivariate HR = 2.5, 95%CI = 1.3-4.7) and PD-1 inhibitors (multivariate HR = 2.0, 95%CI = 1.2-3.2) were associated with the risk of periodontitis. The presence of immune-related periodontitis was associated with better overall survival (not reached vs 17 months, log-rank p-value<0.001), progression-free survival (14.9 vs 5.6 months, log-rank p-value = 0.01), and other concomitant immune-related cutaneous adverse events. In conclusion, ICI was associated with an increased risk of periodontitis. Immune-related periodontitis as an irAE was associated with better cancer survival and concomitant cutaneous irAEs.

Vanadium-Silsesquioxane Nanocages as Heterogeneous Catalysts for Synthesis of Quinazolinones.

The functionalization of polyoxovanadate clusters is promising but of great challenge due to the versatile coordination geometry and oxidation state of vanadium. Here, two unprecedented silsesquioxane ligand-protected "fully reduced" polyoxovanadate clusters were fabricated via a facial solvothermal methodology. The initial mixture of the two polyoxovanadate clusters with different colors and morphologies (green plate V14 and blue block V6) was successfully separated as pure phases by meticulously controlling the assembly conditions. Therein, the V14 cluster is the highest-nuclearity V-silsesquioxane cluster to date. Moreover, the transformation from a dimeric silsesquioxane ligand-protected V14 cluster to a cyclic hexameric silsesquioxane ligand-protected V6 cluster was also achieved, and the possible mechanism termed "ligand-condensation-involved dissociation reassembly" was proposed to explain this intricate conversion process. In addition, the robust V6 cluster was served as a heterogeneous catalyst for the synthesis of important heterocyclic compounds, quinazolinones, starting from 2-aminobenzamide and aldehydes. The V6 cluster exhibits high activity and selectivity to access pure quinazolinones under mild conditions, where the high selectivity was attributed to the confinement effect of the macrocyclic silsesquioxane ligand constraining the molecular freedom of the reaction species. The stability and recyclability as well as the tolerance of a wide scope of aldehyde substrates endow the V6 cluster with a superior performance and appreciable potential in catalytic applications.

Assembly of the bacterial ribosome with circularly permuted rRNA.

Co-transcriptional assembly is an integral feature of the formation of RNA-protein complexes that mediate translation. For ribosome synthesis, prior studies have indicated that the strict order of transcription of rRNA domains may not be obligatory during bacterial ribosome biogenesis, since a series of circularly permuted rRNAs are viable. In this work, we report the structural insights into assembly of the bacterial ribosome large subunit (LSU) based on cryo-EM density maps of intermediates that accumulate during in vitro ribosome synthesis using a set of circularly permuted (CiPer) rRNAs. The observed ensemble of 23 resolved ribosome large subunit intermediates reveals conserved assembly routes with an underlying hierarchy among cooperative assembly blocks. There are intricate interdependencies for the formation of key structural rRNA helices revealed from the circular permutation of rRNA. While the order of domain synthesis is not obligatory, the order of domain association does appear to proceed with a particular order, likely due to the strong evolutionary pressure on efficient ribosome synthesis. This work reinforces the robustness of the known assembly hierarchy of the bacterial large ribosomal subunit and offers a coherent view of how efficient assembly of CiPer rRNAs can be understood in that context.