The relationship between intraoperative hypothermia and postoperative delirium: The PNDRFAP study.

OBJECTIVE: Our study aimed to investigate the correlation between intraoperative hypothermia and postoperative delirium (POD) in patients undergoing general anesthesia for gastrointestinal surgery. METHODS: The study comprised 750 participants from the Perioperative Neurocognitive Disorder Risk Factor and Prognosis (PNDRFAP) study database, which ultimately screened 510 individuals in the final analysis. Preoperative cognitive function was evaluated using the Mini-Mental State Examination (MMSE). The occurrence of POD was determined using the Confusion Assessment Method, and the severity of POD was evaluated using the Memorial Delirium Assessment Scale. Logistic regression was employed to scrutinize the association between intraoperative hypothermia and the incidence of POD, and the sensitivity analysis was conducted by introducing adjusted confounding variables. Decision curves and a nomogram model were utilized to assess the predictive efficacy of intraoperative hypothermia for POD. Mediation analysis involving 10,000 bootstrapped iterations was employed to appraise the suggested mediating effect of numeric rating scale (NRS) scores at 24 and 48 h post-surgeries. The receiver-operating characteristic (ROC) was utilized to evaluate the effectiveness of intraoperative hypothermia in predicting POD. RESULTS: In the PNDRFAP study, the occurrence of POD was notably higher in the intraoperative hypothermia group (62.2%) compared to the intraoperative normal body temperature group (9.8%), with an overall POD incidence of 17.6%. Logistic regression analysis, adjusted for various confounding factors (age [40-90], gender, education, MMSE, smoking history, drinking history, hypertension, diabetes, and the presence of cardiovascular heart disease), demonstrated that intraoperative hypothermia significantly increased the risk of POD (OR = 4.879, 95% CI = 3.020-7.882, p < .001). Mediation analyses revealed that the relationship between intraoperative hypothermia and POD was partially mediated by NRS 24 h after surgery, accounting for 14.09% of the association (p = .002). The area under the curve of the ROC curve was 0.685, which confirmed that intraoperative hypothermia could predict POD occurrence to a certain extent. Decision curve and nomogram analyses, conducted using the R package, further substantiated the predictive efficacy of intraoperative hypothermia on POD. CONCLUSION: Intraoperative hypothermia may increase the risk of POD, and this association may be partially mediated by NRS scores 24 h after surgery.

Reshaping the Tumor Microenvironment of KRASG12D Pancreatic Ductal Adenocarcinoma with combined SOS1 and MEK Inhibition for Improved Immunotherapy Response.

KRAS inhibitors have demonstrated exciting pre-clinical and clinical responses, although resistance occurs rapidly. Here, we investigate the effects of KRAS-targeting therapies on the tumor microenvironment using a library of KRASG12D, p53 mutant, murine PDAC-derived cell lines (KPCY) to leverage immune-oncology combination strategies for long-term tumor efficacy. Our findings show that SOS1 and MEK inhibitors (SOS1i+MEKi) suppressed tumor growth in syngeneic models and increased intra-tumoral CD8+ T cells without durable responses. scRNA-sequencing revealed an increase in inflammatory cancer associated fibroblasts (iCAFs), M2 macrophages, and a decreased dendritic cell quality that ultimately resulted in a highly immunosuppressive microenvironment driven by IL6+ iCAFs. Agonist CD40 treatment was effective to revert macrophage polarization and overcome the lack of mature antigen presenting DCs after SOS1i+MEKi therapy. Treatment increased the overall survival of KPCY tumor-bearing mice. The addition of checkpoint blockade to SOS1i+MEKi combination resulted in tumor free mice with established immune memory. Our data suggests that KRAS inhibition affects myeloid cell maturation and highlights the need for combining KRAS cancer-targeted therapy with myeloid activation to enhance and prolong anti-tumor effects.

Origin of functional de novo genes in humans from "hopeful monsters".

For a long time, it was believed that new genes arise only from modifications of preexisting genes, but the discovery of de novo protein-coding genes that originated from noncoding DNA regions demonstrates the existence of a "motherless" origination process for new genes. However, the features, distributions, expression profiles, and origin modes of these genes in humans seem to support the notion that their origin is not a purely "motherless" process; rather, these genes arise preferentially from genomic regions encoding preexisting precursors with gene-like features. In such a case, the gene loci are typically not brand new. In this short review, we will summarize the definition and features of human de novo genes and clarify their process of origination from ancestral non-coding genomic regions. In addition, we define the favored precursors, or "hopeful monsters," for the origin of de novo genes and present a discussion of the functional significance of these young genes in brain development and tumorigenesis in humans. This article is categorized under: RNA Evolution and Genomics > RNA and Ribonucleoprotein Evolution.

Case report: detection of multiple sporadic gastrointestinal stromal tumors by dual-time 18 F-FDG PET/CT.

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors affecting the gastrointestinal tract. Typically, GISTs are solitary; however, in rare cases, they may be multiple and appear in one or more organs. Multiple GISTs can appear in familial GISTs, children, or certain tumor syndromes such as neurofibromatosis type 1, Carney syndrome, and Carney-Stratakis syndrome. However, the diagnosis of primary multiple sporadic GISTs is often more difficult than that of these diseases. Herein, we report a case of multiple primary sporadic GISTs in a 64-year-old man, affecting the abdominal cavity and retroperitoneum, as identified through dual-time point positron emission tomography (PET) with 18F-labeled fluoro-2-deoxyglucose (18F-FDG) and computed tomography (18F-FDG PET/CT). Notably, the dual-time-point PET/CT revealed the migration of masses near the lower abdomen into the abdominal cavity. Furthermore, a significant increase in radioactive uptake of the mass 3 h after 18F-FDG injection compared with that 1 h after injection may be an important cue for its diagnosis.

Multilocular thymic cysts can be easily misdiagnosed as malignant tumor on computer tomography: A case report.

BACKGROUND: Multilocular thymic cyst (MTC) is a rare mediastinal lesion which is considered to occur in the process of acquired inflammation. It is usually characterized by well-defined cystic density and is filled with transparent liquid. CASE SUMMARY: We report on a 39-year-old male with a cystic-solid mass in the anterior mediastinum. Computer tomography (CT) imaging showed that the mass was irregular with unclear boundaries. After injection of contrast agent, there was a slight enhancement of stripes and nodules. According to CT findings, it was diagnosed as thymic cancer. CONCLUSION: After surgery, MTC accompanied by bleeding and infection was confirmed by pathological examination. The main lesson of this case was that malignant thymic tumor and MTC of the anterior mediastinum sometimes exhibit similar CT findings. Caution is necessary in clinical work to avoid misdiagnosis.

Allogeneic haematopoietic stem cell transplantation for adult T-lymphoblastic lymphoma: A real-world multicentre analysis in China.

In this multicentre, real-world study, we aimed to identify the clinical outcomes and safety of allogeneic haematopoietic stem cell transplantation (allo-HSCT) in T-lymphoblastic lymphoma (T-LBL). A total of 130 Ann Arbor stage III or IV T-LBL patients (>16 years) treated with allo-HSCT across five transplant centres were enrolled. The 2-year cumulative incidence of disease progression, the probabilities of progression-free survival (PFS), overall survival (OS) and non-relapse mortality (NRM) after allo-HSCT were 21.0%, 69.8%, 79.5% and 9.2% respectively. Patients with central nervous system (CNS) involvement had a higher cumulative incidence of disease progression compared with those without CNS involvement (57.1% vs. 18.9%, HR 3.78, p = 0.014). Patients receiving allo-HSCT in non-remission (NR) had a poorer PFS compared with those receiving allo-HSCT in complete remission (CR) or partial remission (49.2% vs. 72.7%, HR 2.21, p = 0.041). Particularly for patients with bone marrow involvement and achieving CR before allo-HSCT, measurable residual disease (MRD) positivity before allo-HSCT was associated with a poorer PFS compared with MRD negativity (62.7% vs. 86.8%, HR 1.94, p = 0.036). On multivariate analysis, CNS involvement at diagnosis and receiving allo-HSCT in NR were associated with disease progression. Thus, our real-world data suggested that allo-HSCT appeared to be an effective therapy for adult T-LBL patients with Ann Arbor stage III or IV disease.

Relocation of polyotia tissue to reconstruct the tragus and fill the preauricular depression.

OBJECTIVES: The present article introduces a lingual composite tissue flap based on the tragus-like structure for correcting polyotia deformity, with the aim of providing a surgical technique that involves relocating polyotia tissue to reconstruct the tragus and fill the preauricular depression. METHODS: The study included a total of 21 patients with polyotia who underwent lingual composite tissue flap reconstruction between January 2020 to December 2022. Patients were retrospectively assessed through a comprehensive review of their medical records and photographic data. Tragus morphology was evaluated based on the measurements of tragus length and width. The Aesthetic Outcomes Scale (AOS), modified Vancouver Scar Scale (mVSS), and Visual Analogue Scale (VAS) were employed for the assessment of surgical outcomes. RESULTS: The follow-up period for all patients ranged from 6 to 15 months. The length and width of the normal tragus were not significantly different from those of the reconstructed tragus. The mean preoperative AOS score was 2.73 ± 0.51, while the mean postoperative AOS score increased to 7.61 ± 0.65. The mVSS yielded an average score of 1.80 ± 1.43, indicating inconspicuous scarring post polyotia surgery. The preoperative VAS satisfaction score was recorded as 1.57 ± 0.67, while the postoperative VAS score significantly increased to 8.33 ± 0.91. The flaps all successfully survived post-operation without any occurrences of flap hematoma, necrosis, infection, or wound dehiscence. CONCLUSION: The reconstruction of the tragus should be given careful consideration when addressing polyotia. The utilization of a lingual composite tissue flap for correction can achieve excellent aesthetic results for the tragus, with high patient satisfaction and minimal complications.

The Association of Intraindividual Difference Between Cystatin- and Creatinine-Based Estimated GFR and Contrast-Associated Acute Kidney Injury.

Purpose: The estimated glomerular filtration rate (eGFR) based on creatinine is crucial for the risk assessment of contrast-associated acute kidney injury (CA-AKI). In recent, the difference between cystatin C-based eGFR (eGFRcys) and creatinine-based eGFR (eGFRcr) has been widely documented. We aimed to explore whether intraindividual differences between eGFRcys and eGFRcr had potential value for CA-AKI risk assessment in patients undergoing elective percutaneous coronary intervention (PCI). Patients and Methods: From January 2012 to December 2018, we retrospectively observed 5049 patients receiving elective PCI. To determine eGFR, serum creatinine and cystatin C levels were measured. CA-AKI was defined as serum creatinine being increased ≥ 50% or 0.3 mg/dL within 48 h after contrast agents exposure. Chronic kidney disease (CKD) was defined as the eGFR < 60 mL/min/1.73 m2. Results: Approximately half of the participants (2479, 49.1%) had a baseline eGFRdiff (eGFRcys-eGFRcr) between -15 and 15 mL/min/1.73 m2. Restricted cubic splines analysis revealed a nonlinear relationship between eGFRdiff and CA-AKI. Multivariable logistic regression analysis indicated that compared with the reference group (-15 to 15 mL/min/1.73 m2), the negative-eGFRdiff group (less than -15 mL/min/1.73 m2) had a higher risk of CA-AKI (OR, 3.44; 95% CI, 2.57-4.64). Furthermore, patients were divided into four groups based on CKD identified by eGFRcys or eGFRcr. Multivariable logistic analysis revealed that patients with either CKDcys (OR, 2.94; 95% CI, 2.19-3.95, P < 0.001) or CKDcr (OR, 2.44; 95% CI, 1.19-4.63, P < 0.001) had an elevated risk of CA-AKI compared to those without CKDcys and CKDcr. Conclusion: There are frequent intraindividual differences between eGFRcys and eGFRcr, and these differences can be used to forecast the risk of CA-AKI.

Overexpression of Wnt5a promoted the protective effect of mesenchymal stem cells on Lipopolysaccharide-induced endothelial cell injury via activating PI3K/AKT signaling pathway.

BACKGROUND: Lung endothelial barrier injury plays an important role in the pathophysiology of acute lung injury/acute respiratory distress syndrome (ALI/ARDS). Mesenchymal stem cells (MSCs) therapy has shown promise in ARDS treatment and restoration of the impaired barrier function. It has been reported that Wnt5a shows protective effects on endothelial cells. Therefore, the study aimed to investigate whether overexpression of Wnt5a could promote the protective effects of MSCs on Lipopolysaccharide (LPS)-induced endothelial cell injury. METHODS: To evaluate the protective effects of MSCs overexpressing Wnt5a, we assessed the migration, proliferation, apoptosis, and angiogenic ability of endothelial cells. We assessed the transcription of protective cellular factors using qPCR and determined the molecular mechanism using Western blot analysis. RESULTS: Overexpression of Wnt5a upregulated the transcription of protective cellular factors in MSCs. Co-culture of MSCWnt5a promoted endothelial migration, proliferation and angiogenesis, and inhibited endothelial cell apoptosis through the PI3K/AKT pathway. CONCLUSIONS: Overexpression of Wnt5a promoted the therapeutic effect of MSCs on endothelial cell injury through the PI3K/AKT signaling. Our study provides a novel approach for utilizing genetically modified MSCs in the transplantation therapy for ARDS.

Comparison of different preoperative objective nutritional indices for evaluating 30-d mortality and complications after liver transplantation.

BACKGROUND: The nutritional status is closely related to the prognosis of liver transplant recipients, but few studies have reported the role of preoperative objective nutritional indices in predicting liver transplant outcomes. AIM: To compare the predictive value of various preoperative objective nutritional indicators for determining 30-d mortality and complications following liver transplantation (LT). METHODS: A retrospective analysis was conducted on 162 recipients who underwent LT at our institution from December 2019 to June 2022. RESULTS: This study identified several independent risk factors associated with 30-d mortality, including blood loss, the prognostic nutritional index (PNI), the nutritional risk index (NRI), and the control nutritional status. The 30-d mortality rate was 8.6%. Blood loss, the NRI, and the PNI were found to be independent risk factors for the occurrence of severe postoperative complications. The NRI achieved the highest prediction values for 30-d mortality [area under the curve (AUC) = 0.861, P < 0.001] and severe complications (AUC = 0.643, P = 0.011). Compared to those in the high NRI group, the low patients in the NRI group had lower preoperative body mass index and prealbumin and albumin levels, as well as higher alanine aminotransferase and total bilirubin levels, Model for End-stage Liver Disease scores and prothrombin time (P < 0.05). Furthermore, the group with a low NRI exhibited significantly greater incidences of intraabdominal bleeding, primary graft nonfunction, and mortality. CONCLUSION: The NRI has good predictive value for 30-d mortality and severe complications following LT. The NRI could be an effective tool for transplant surgeons to evaluate perioperative nutritional risk and develop relevant nutritional therapy.

Radiomics derived from T2-FLAIR: the value of 2- and 3-classification tasks for different lesions in multiple sclerosis.

Background: White matter (WM) lesions can be classified into contrast enhancement lesions (CELs), iron rim lesions (IRLs), and non-iron rim lesions (NIRLs) based on different pathological mechanism in relapsing-remitting multiple sclerosis (RRMS). The application of radiomics established by T2-FLAIR to classify WM lesions in RRMS is limited, especially for 3-class classification among CELs, IRLs, and NIRLs. Methods: A total of 875 WM lesions (92 CELs, 367 IRLs, 416 NIRLs) were included in this study. The 2-class classification was only performed between IRLs and NIRLs. For the 2- and 3-class classification tasks, all the lesions were randomly divided into training and testing sets with a ratio of 8:2. We used least absolute shrinkage and selection operator (LASSO), reliefF algorithm, and mutual information (MI) for feature selection, then eXtreme gradient boosting (XGBoost), random forest (RF), and support vector machine (SVM) were used to establish discrimination models. Finally, the area under the curve (AUC), accuracy, sensitivity, specificity, and precision were used to evaluate the performance of the models. Results: For the 2-class classification model, LASSO classifier with RF model showed the best discrimination performance with the AUC of 0.893 (95% CI: 0.838-0.942), accuracy of 0.813, sensitivity of 0.833, specificity of 0.781, and precision of 0.851. However, the 3-class classification model of LASSO with XGBoost displayed the highest performance with the AUC of 0.920 (95% CI: 0.887-0.950), accuracy of 0.796, sensitivity of 0.839, specificity of 0.881, and precision of 0.846. Conclusions: Radiomics models based on T2-FLAIR images have the potential for discriminating among CELs, IRLs, and NIRLs in RRMS.

Exploring the Therapeutic Potential of Royal Jelly in Metabolic Disorders and Gastrointestinal Diseases.

Metabolic disorders, encompassing diabetes mellitus, cardiovascular diseases, gastrointestinal disorders, etc., pose a substantial global health threat, with rising morbidity and mortality rates. Addressing these disorders is crucial, as conventional drugs often come with high costs and adverse effects. This review explores the potential of royal jelly (RJ), a natural bee product rich in bioactive components, as an alternative strategy for managing metabolic diseases. RJ exhibits diverse therapeutic properties, including antimicrobial, estrogen-like, anti-inflammatory, hypotensive, anticancer, and antioxidant effects. This review's focus is on investigating how RJ and its components impact conditions like diabetes mellitus, cardiovascular disease, and gastrointestinal illnesses. Evidence suggests that RJ serves as a complementary treatment for various health issues, notably demonstrating cholesterol- and glucose-lowering effects in diabetic rats. Specific RJ-derived metabolites, such as 10-hydroxy-2-decenoic acid (10-HDA), also known as the "Queen bee acid," show promise in reducing insulin resistance and hyperglycemia. Recent research highlights RJ's role in modulating immune responses, enhancing anti-inflammatory cytokines, and suppressing key inflammatory mediators. Despite these promising findings, further research is needed to comprehensively understand the mechanisms underlying RJ's therapeutic effects.

Laparoscopic repair of perineal hernia and unilateral inguinal hernia after rectal cancer surgery: A case report.

INTRODUCTION: Perineal hernia (PH) is a rare complication that can occur after abdominoperineal resection for rectal cancer. Laparoscopic repair of PHs has gained increasing popularity compared to open approaches due to advantages such as superior visualization, decreased invasiveness, and faster recovery. This case report highlights the successful use of laparoscopic tension-free mesh repair for concurrent perineal and inguinal hernias after rectal cancer surgery. CASE DESCRIPTION: A 51-year-old man underwent laparoscopic-assisted abdominoperineal resection for rectal cancer. About 2 months postoperatively, he developed reducible masses in the perineal and left groin regions, associated with urinary symptoms and sensation of prolapse. Physical exam revealed protruding masses that enlarged with Valsalva. Pelvic CT confirmed PH and left inguinal hernia. INTERVENTIONS: Laparoscopic tension-free repair of the PH and inguinal hernia was performed on this patient. The repair was completed by the steps of adhesion separation, mesh placement, and fixation. OUTCOMES: The 98-minute surgery was successful without complications. The patient recovered well, ambulating on postoperative day 2 and getting discharged on day 6. CONCLUSION: This case demonstrates that laparoscopic tension-free repair with mesh is an effective approach for treating PH and concurrent inguinal hernia following rectal cancer surgery, resulting in successful outcomes and low recurrence rates. The laparoscopic technique provides benefits of minimal invasiveness and rapid recovery.

Using Auricular Cartilage-fascia Composite Tissue Free Grafting Technique to Improve Cartilage Survival Outcomes.

OBJECTIVES: Auricular cartilage graft has a wide range of applications in plastic and reconstructive surgery. However, there is still a risk of absorption of the grafts over time. Intrinsic postauricular fascia (IPF) with a rich vascular network may play an important role in the nutrition and repair of auricular cartilage. This study aimed to investigate the effect of IPF on the survival viability of free auricular cartilage grafts. METHODS: 24 auricular cartilages were obtained from 6 New Zealand white rabbits which were divided into the cartilage-fascia composite graft group (FC group, n=12) and the cartilage without fascia group (C group, n=12). Two groups of cartilage were implanted into each side of the subcutaneous pocket of the rabbit's dorsum. The rabbits were sacrificed after 3 months and all cartilage grafts were obtained. Macroscopic observation, histopathological staining, and biomechanical testing were performed on all specimens. RESULTS: There were significant differences between the 2 groups regarding proliferating chondrocytes, apoptotic chondrocytes, vascularization, and matrix collagen. Compared to the auricular cartilage grafts without fascia, the auricular cartilage-fascia composite grafts had more neovascularization, proliferative chondrocytes, and type II collagen, with a homogeneous cartilage matrix and no obvious areas of heterogeneous staining. Young's modulus and ultimate tensile strength of cartilage were reduced in both groups compared to pretransplantation, but the composite graft group was superior to the fascia-free group. CONCLUSIONS: Auricular cartilage-fascial composite tissue free graft could improve cartilage survival outcomes with higher viability and mechanical properties.

Flavor formation of tilapia byproduct hydrolysates in Maillard reaction.

The Maillard reaction (MR) of tilapia byproduct protein hydrolysates was investigated for the use of byproduct protein as a food ingredient and to mask its fishy odor and bitter flavor. The flavor differences in tilapia byproduct hydrolysates before and after the MR were analyzed to explore the key flavor precursor peptides and amino acids involved in MR. The results suggested that eight key volatile substances, including 2,5-dimethylpyrazine, 2-pentylfuran, hexanal, octanal, nonanal, (E)-2-decenal, decanal, and 1-octen-3-ol contributed most to the MR products group (ROAV > 1). Ten volatile compounds, including 1-octen-3-ol, hexanal, 2-pentylfuran, 2,5-dimethylpyrazine, methyl decanoate, and 2-octylfuran, were the flavor markers that distinguished the different samples (VIP > 1). The four most consumed peptides were VAPEEHPTL, GPIGPRGPAG, KSADDIKKAF, and VWEGQNIVK. Umami peptides and bitter free amino acids (FAAs) were the key flavor precursor peptide and FAAs, respectively. Overall, the hydrolysates of tilapia byproducts with flavor improved by MR are a promising strategy for the production of flavorings.

Safety of nighttime elective hepatectomy for hepatocellular carcinoma patients: a retrospective study.

Purpose: This study aimed to investigate whether nighttime elective surgery influenced the short-term outcomes and prognosis of hepatocellular carcinoma (HCC) patients. Methods: The 1,339 HCC patients who underwent hepatectomy were divided into the daytime surgery group (8 a.m.-6 p.m., n = 1,105) and the nighttime surgery group (after 6 p.m., n = 234) based on the start time of surgery. The 1:2 propensity score matching (PSM) analysis was used to control confounding factors. The short-term outcomes of HCC patients in the 2 groups were compared before and after PSM. Factors associated with major complications (Clavien-Dindo grade, ≥III) and textbook oncologic outcomes (TOO) were separately identified by multivariable logistic regression based on variables screened via least absolute shrinkage and selection operator (LASSO). The Kaplan-Meier method was used to analyze overall survival (OS) and recurrence-free survival (RFS). Results: TOO was achieved after surgery in 897 HCC patients. HCC patients in the nighttime surgery group had a higher body mass index (P = 0.010). After 1:2 PSM, the baseline characteristics of patients between the 2 groups were similar. Short-term outcomes in HCC patients were comparable both before and after PSM (all Ps > 0.05), as were TOO in the 2 groups before (P = 0.673) and after PSM (P = 0.333). In our LASSO-logistic regression, nighttime surgery was not an independent factor associated with major complications or TOO. Both groups also had similar OS (P = 0.950) and RFS (P = 0.740) after PSM. Conclusion: Our study revealed the safety of nighttime elective hepatectomy for HCC patients.

Effect of a collagen peptide-fish oil high internal phase emulsion on the printability and gelation of 3D-printed surimi gel inks.

The effect of a high internal phase emulsion (HIPE) on three-dimensional-printed surimi gel inks was studied. Increasing the concentration of collagen peptide decreased the particle size of HIPE droplets and improved the viscoelasticity and stability. For example, when the collagen peptide concentration was 5 wt%, the viscoelasticity of the HIPE was high, as indicated by the presence of small and uniform particles, which formed a monolayer in the outer layer of the oil droplets to form stable a HIPE. A HIPE was used as the filling material to fill the surimi gel network, which reduced the porosity of the network. Surimi protein and peptides have dual emulsifying effects on the stabilization of oil. After adding the emulsion, the texture, gel properties and rheological properties of the surimi were reduced, and its printing adaptability was improved. This study provides new ideas for the production of surimi and its application in 3D printing.

Functional and Promiscuity Studies of Three-Residue Cyclophane Forming Enzymes Show Nonnative C-C Cross-Linked Products and Leader-Dependent Cyclization.

Enzymes catalyzing peptide macrocyclization are important biochemical tools in drug discovery. The three-residue cyclophane-forming enzymes (3-CyFEs) are an emerging family of post-translational modifying enzymes that catalyze the formation of three-residue peptide cyclophanes. In this report, we introduce three additional 3-CyFEs, including ChlB, WnsB, and FnnB, that catalyze cyclophane formation on Tyr, Trp, and Phe, respectively. To understand the promiscuity of these enzymes and those previously reported (MscB, HaaB, and YxdB), we tested single amino acid substitutions at the three-residue motif of modification (Ω1X2X3, Ω1 = aromatic). Collectively, we observe that substrate promiscuity is observed at the Ω1 and X2 positions, but a greater specificity is observed for the X3 residue. Two nonnative cyclophane products were characterized showing a Phe-C3 to Arg-Cß and His-C2 to Pro-Cß cross-links, respectively. We also tested the leader dependence of selected 3-CyFEs and show that a predicted helix region is important for cyclophane formation. These results demonstrate the biocatalytic potential of these maturases and allow rational design of substrates to obtain a diverse array of genetically encoded 3-residue cyclophanes.

Apical papilla stem cell-derived exosomes regulate lipid metabolism and alleviate inflammation in the MCD-induced mouse NASH model.

Stem cells from the apical papilla(SCAPs) exhibit remarkable tissue repair capabilities, demonstrate anti-inflammatory and pro-angiogenic effects, positioning them as promising assets in the realm of regenerative medicine. Recently, the focus has shifted towards exosomes derived from stem cells, perceived as safer alternatives while retaining comparable physiological functions. This study delves into the therapeutic implications of exosomes derived from SCAPs in the methionine-choline-deficient (MCD) diet-induced mice non-alcoholic steatohepatitis (NASH) model. We extracted exosomes from SCAPs. During the last two weeks of the MCD diet, mice were intravenously administered SCAPs-derived exosomes at two distinct concentrations (50 µg/mouse and 100 µg/mouse) biweekly. Thorough examinations of physiological and biochemical indicators were performed to meticulously evaluate the impact of exosomes derived from SCAPs on the advancement of NASH in mice induced by MCD diet. This findings revealed significant reductions in body weight loss and liver damage induced by the MCD diet following exosomes treatment. Moreover, hepatic fat accumulation was notably alleviated. Mechanistically, the treatment with exosomes led to an upregulation of phosphorylated adenosine monophosphate-activated protein kinase (p-AMPK) levels in the liver, enhancing hepatic fatty acid oxidation and transporter gene expression while inhibiting genes associated with fatty acid synthesis. Additionally, exosomes treatment increased the transcription levels of key liver mitochondrial marker proteins and the essential mitochondrial biogenesis factor. Furthermore, the levels of serum inflammatory factors and hepatic tissue inflammatory factor mRNA expression were significantly reduced, likely due to the anti-inflammatory phenotype induced by exosomes in macrophages. The above conclusion suggests that SCAPs-exosomes can improve NASH.