Ferrostatin-1 Reversed Chronic Intermittent Hypoxia-Induced Ferroptosis in Aortic Endothelial Cells via Reprogramming Mitochondrial Function.

Purpose: Chronic intermittent hypoxia (CIH) related arterial endothelium injury is a common cause of cardiovascular system injury. However, the mechanism still needs to be clarified. In this study, we aimed to clarify the role and mechanism of ferrostatin-1 (Fer-1) in CIH-related rat arterial endothelial cells (ROAEC) ferroptosis. Methods: ROAEC was divided into control group, CIH group, and CIH+ Fer-1 group. Cell viability was detected by cell counting kit 8 kits (CCK8). The apoptotic rate, reactive oxygen species (ROS) levels, Fe2+ levels, and lipid ROS levels were detected by flow cytometry. Malondialdehyde (MDA) levels and nicotinamide adenine dinucleotide (NAD+)/NADH ratio were detected via Elisa kits. The mRNA and protein levels of cystine/glutamate antiporter solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) were detected by qRT-PCR and Western blot. Mitochondrial structure and function were observed by transmission electron microscope (TEM) and mitochondrial membrane potential (MMP). Central carbon metabolism was measured to compare metabolites among each group. Results: After the CIH exposure, ROAEC cell viability decreased; The levels of cell apoptosis, ROS, Fe2+, MDA, and lip ROS increased; The levels of NAD+/NADP ratio decreased; The mRNA and protein levels of GPX4 and SLC7A11 decreased (all p<0.05). Co-cultured with Fer-1 reversed the levels of apoptosis rate, cell viability, ROS, Fe2+, MAD, lipid ROS, NAD+/NADH ratio and the mRNA and protein expression of GPX4 and SLC7A11 (all p<0.05). The TEM results showed that damaged mitochondrial membrane and the matrix spillover in the CIH group. The results of the JC-1 assay showed decreased MMP in the CIH group. Fer-1 treatment ameliorated the mitochondrial injury. The results of central carbon metabolism found that CIH altered the metabolites in the TCA cycle, which were reversed by Fer-1 treatment. Conclusion: CIH-induced ferroptosis in ROAEC, which were reversed by Fer-1 via reprogramming mitochondrial function.

Circular RNA_0025843 Alleviated Cigarette Smoke Extract Induced Bronchoalveolar Epithelial Cells Ferroptosis.

Purpose: Circular RNA (circRNA) plays an important role in various biological processes. However, their functions in cigarette smoke extract (CSE) induced human normal lung epithelial cells (BEAS-2B) injury remain vague. The study aimed to explore circRNA expression profiles and reveal their potential roles in CSE-treated BEAS-2B cells. Methods: 5% CSE exposure for 24 hours were used to build the BEAS-2B cells ferroptosis model. Differentially expressed circRNAs (DECs) were identified by next-generation RNA sequencing. Six randomly selected DECs were validated via quantitative reverse transcription polymerase chain reaction (qRT-PCR). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and Gene Ontology (GO) analysis were conducted to clarify the potential functions of the DECs. Furthermore, the role of hsa_circ_0025843 in CSE-related BEAS-2B cells ferroptosis was confirmed. Results: 5% CSE exposure induced BEAS-2B cells ferroptosis. Fifty-one up-regulated cirRNAs and 80 down-regulated circRNAs were revealed in CSE-treated BEAS-2B cells. Hsa_circ_0003461, hsa_circ_0007548, hsa_circ_0025843, hsa_circ_0068896, hsa_circ_0005832, and hsa_circ_0053378 were selected randomly to validate the reliability of next-generation RNA sequencing by qRT-PCR. After KEGG pathway analysis, DECs were found to participate in the process of EGFR tyrosine kinase inhibitor resistance and glycerophospholipid metabolism. The knockdown of hsa_circ_0025843 significantly alleviated CSE-induced BEAS-2B cells ferroptosis. Conclusion: The study indicated the circRNA expression profiles in CSE-treated BEAS-2B cells. Hsa_circ_0025843 alleviated CSE induced BEAS-2B cells ferroptosis, which might be a potential therapeutic target of CSE related lung injury.

A method for screening CDV microneutralization activity in microvolume samples.

OBJECTIVE: This study aims to establish a screening method for canine distemper virus (CDV) microneutralizing activity suitable for microvolume samples. METHODS: This method is based on the Indirect immunofluorescence assay (IFA) established on Vero-slam cells. First, by comparing the sensitivities of CDV neutralizing monoclonal antibody (1C42H11) and NP protein monoclonal antibody (CDV-NP) in IFA experiments, CDV-NP was selected as the primary antibody. Then, by detecting the infection rates of multi-concentrations of CDV neutralized with water, the minimum CDV concentration with an infection rate greater than 90% was defined as the minimum stable infection concentration, which was used as the neutralizing solution for this method. Finally, the CDV-positive neutralizing serum (neutralizing titer 1:708) was diluted into multiple dilution groups as test samples, and then neutralized in equal volumes with the neutralizing solution to detect the neutralizing activity detection rates of each dilution group and the lowest detection limit of this method. RESULTS: The results showed that the neutralizing activity of serum with a CDV neutralizing titer of 1:708 diluted 212 times was the lowest limit of detection, and the detection rate of microneutralizing activity was 63.54 ± 4.774%. CONCLUSION: This study established an economical, stable, and easy-to-operate CDV microneutralizing activity high-throughput screening method, laying a methodological foundation for the development of native CDV neutralizing antibodies based on single B cells.

A portable intelligent hydrogel platform for multicolor visual detection of HAase.

Hyaluronidase (HAase) is an important endoglycosidase involved in numerous physiological and pathological processes, such as apoptosis, senescence, and cancer progression. Simple, convenient, and sensitive detection of HAase is important for clinical diagnosis. Herein, an easy-to-operate multicolor visual sensing strategy was developed for HAase determination. The proposed sensor was composed of an enzyme-responsive hydrogel and a nanochromogenic system (gold nanobipyramids (AuNBPs)). The enzyme-responsive hydrogel, formed by polyethyleneimine-hyaluronic acid (PEI-HA), was specifically hydrolyzed with HAase, leading to the release of platinum nanoparticles (PtNPs). Subsequently, PtNPs catalyzed the mixed system of 3,3',5,5'-tetramethylbenzidine (TMB) and H2O2 to produce TMB2+ under acidic conditions. Then, TMB2+ effectively etched the AuNBPs and resulted in morphological changes in the AuNBPs, accompanied by a blueshift in the localized surface plasmon resonance peak and vibrant colors. Therefore, HAase can be semiquantitatively determined by directly observing the color change of AuNBPs with the naked eye. On the basis of this, the method has a linear detection range of HAase concentrations between 0.6 and 40 U/mL, with a detection limit of 0.3 U/mL. In addition, our designed multicolor biosensor successfully detected the concentration of HAase in human serum samples. The results showed no obvious difference between this method and enzyme-linked immunosorbent assay, indicating the good accuracy and usability of the suggested method.

Clinical value of soluble urokinase-type plasminogen activator receptor in predicting sepsis-associated acute kidney injury.

BACKGROUND: Sepsis-associated acute kidney injury (S-AKI) is a critical illness and is often associated with high morbidity and mortality rates. The soluble urokinase-type plasminogen activator receptor (suPAR) is an important immune mediator and is involved in kidney injury. However, its diagnostic value in S-AKI patients remains unclear. Therefore, we assessed the early predictive value of suPAR for S-AKI patients. METHODS: We prospectively enrolled adult patients, immediately after fulfilling the sepsis-3 criteria. Plasma suPAR levels at 0-, 12-, 24-, and 48-h post-sepsis diagnosis were measured. S-AKI development was the primary outcome. S-AKI risk factors were analyzed using logistic regression, and the value of plasma suPAR for early S-AKI diagnosis was assessed using receiver operating characteristic (ROC) curves. RESULTS: Of 179 sepsis patients, 63 (35.2%) developed AKI during hospitalization. At 12-, 24-, and 48-h post-sepsis diagnosis, plasma suPAR levels were significantly higher in patients with S-AKI than in patients without S-AKI (p < 0.05). The plasma suPAR had the highest area under the ROC curve of 0.700 (95% confidence interval (CI), 0.621-0.779) at 24-h post-sepsis diagnosis, at which the best discrimination ability for S-AKI was achieved with suPAR of ≥6.31 ng/mL (sensitivity 61.9% and specificity 71.6%). Logistic regression analysis showed that suPAR at 24-h post-sepsis diagnosis remained an independent S-AKI risk factor after adjusting for mechanical ventilation, blood urea nitrogen, and pH. CONCLUSIONS: The findings suggest that plasma suPAR may be a potential biomarker for early S-AKI diagnosis.

Dynamic response of axle box bearing for high-speed train considering wheelset flexibility and polygonal wear.

In this study, a flexible wheelset was added to a rigid-flexible coupled vehicle dynamics model, in which the axle box bearings are accurately modeled. The measured wheel's polygon wear profile and Wuhan-Guangzhou track spectrum are used in the model to define the wheel tread and track irregularity, respectively. We conducted a field test on the Wuhan-Guangzhou railway line to validate the model. Then, we investigate how the dynamic properties of the axle box bearing are impacted by the wheelset flexibility and polygonal wear of wheel. We found that the polygonal wheel with a rigid wheelset causes high-frequency vibration in wheelset and axle box, and increases the axle box bearing's internal contact force. Additionally, the flexible wheelset with a normal wheel tread can alleviate the wheel/rail impact and reduce the axle box's vertical vibration as well as the axle box bearing's internal contact force. When the vehicle is running at v = 300 km/h, the excitation frequency caused by the wheel's 20th-order polygon is 576.5 Hz, and the flexible wheelset's 20th-order modal frequency is 577 Hz. The two frequencies are similar, when considering the polygonal wheel and flexible wheelset simultaneously, the wheelset will resonate. And the resonate of wheelset will increase the local deformation of the axle end and deteriorate the bearing operating environment, causing a significant increase in the bearing contact force. Finally, the axle box bearing's dynamic characteristics are summarized when vehicle velocity varies from 50 to 350 km/h and wheel polygon wear amplitude ranges from 0.01 to 0.05 mm.

Correction: Nitric oxide/paclitaxel micelles enhance anti-liver cancer effects and paclitaxel sensitivity by inducing ferroptosis, endoplasmic reticulum stress and pyroptosis.

[This corrects the article DOI: 10.1039/D3RA04861F.].

Nitric oxide/paclitaxel micelles enhance anti-liver cancer effects and paclitaxel sensitivity by inducing ferroptosis, endoplasmic reticulum stress and pyroptosis.

The objective of this study was to investigate the anticancer activities of biodegradable polymeric micelles composed of monomethoxy poly(ethylene glycol), polylactic acid, and nitric oxide (mPEG-PLA-NO) loaded with paclitaxel (PTX) as a nanomedicine delivery system. We aimed to compare the anticancer effects of these NO/PTX micelles with PTX alone and elucidate their mechanism of action. We evaluated the impact of NO/PTX and PTX on cell viability using Cell Counting Kit-8 (CCK8) assays conducted on the Bel-7402 liver cancer cell line. Additionally, we employed H22 xenografted mice to assess the in vivo tumor growth inhibitory activity of NO/PTX. To examine the cytotoxicity of NO/PTX, the intracellular levels of reactive oxygen species (ROS), and the expression of ferroptosis-related proteins, we conducted experiments in the presence of the ferroptosis inhibitor ferrostatin-1 (Fer-1) or the ROS inhibitor N-acetyl cysteine (NAC). Furthermore, we investigated the expression of endoplasmic reticulum stress (ERS) and apoptosis-associated proteins. Our results demonstrated that NO/PTX exhibited enhanced anticancer effects compared to PTX alone in both Bel-7402 cells and H22 xenografted mice. The addition of Fer-1 or NAC reduced the anticancer activity of NO/PTX, indicating the involvement of ferroptosis and ROS in its mechanism of action. Furthermore, NO/PTX modulated the expression of proteins related to ERS and apoptosis, indicating the activation of these cellular pathways. The anticancer effects of NO/PTX in liver cancer cells were mediated through the induction of ferroptosis, pyroptosis, ERS, and apoptosis-associated networks. Ferroptosis and pyroptosis were activated by treatment of NO/PTX at low concentration, whereas ERS was induced to trigger apoptosis at high concentration. The superior anti-tumor effect of NO/PTX may be attributed to the downregulation of a multidrug resistance transporter and the sensitization of cells to PTX chemotherapy. In summary, our study highlights the potential of mPEG-PLA-NO micelles loaded with PTX as a nanomedicine delivery system for liver cancer treatment. The observed enhancement in anticancer activity, combined with the modulation of key cellular pathways, provides valuable insights into the therapeutic potential of NO/PTX in overcoming resistance and improving treatment outcomes in liver cancer patients.

Genome-wide association study on coordination and agility in 461 Chinese Han males.

There is growing evidence that genetic factors can influence human athletic performance. In many sports performances, excellent coordination and agility are the keys to mastery. However, few studies have been devoted to identifying genetic influences on athletic performance. Methods: We generated a derived measure of coordination and agility from the data of hexagonal jumps and T-runs and conducted genome-wide association and meta-analysis studies focused on coordination and agility. Results: The phenotypic correlation and genetic covariance analysis indicated that hexagonal jumps and T-runs were possibly influenced by the same set of genetic factors (R = 0.27, genetic covariance = 0.59). Meta-analysis identified rs117047321 genome-wide significant association (N = 143, P < 10E-5) with coordination and agility, and this association was replicated in the replication group (N = 318, P < 0.05). The CG genotype samples of this single nucleotide polymorphism (SNP) required a longer average movement time than the CC genotype samples, and the CG genotype only exists in Asia, which may belong to the East Asia-specific variation. This SNP is located on MYO5B, which is highly expressed in tissues such as the brain, heart, and muscle, suggesting that this locus might be a genetic factor related to human energy metabolism. Conclusion: Our study indicated that genetic factors can affect the athletic performance of coordination and agility. These findings may provide valuable insights for using genetic factors to evaluate sports characteristics.

Exploring Restrictions to use of community greenways for physical activity through structural equation modeling.

Public health problems caused by rapid urbanization have attracted increasing amounts of attention. Existing studies show that improving the frequency and duration of physical activity among urban residents can effectively reduce their disease risk. A community greenway, as a green space for public activity directly serving community residents, is one of the best spatial place for bringing health benefits to people. Although the scale and scope of greenway construction have been increasing in recent years, the utilization rate of some greenways is not high for various reasons, restricting the extent to which people engage in healthy physical activities in greenway spaces. In this study, the greenway of Nancheng Community in Wenjiang District, Chengdu city, China was selected as the object of study, and structural equation modeling was conducted to explore the objective environmental factors and individual characteristics acting as barriers to use of the community greenway by the population for physical activity. The results show that user experience, the greenway landscape, and safety and accessibility are important factors that restrict people's willingness engage in physical activity in the community greenway environment. The results of this study provide a direction for further consideration of ways to enhance people's willingness to make use of greenways for physical activity, and further provide a theoretical basis for the healthy design and transformation of community greenway spaces.

Scanning iron response regulator binding sites using Dap-seq in the Brucella genome.

Iron is an essential element required for all organisms. Iron response regulator (Irr) is a crucial transcriptional regulator and can affect the growth and iron uptake of Brucella. The growth rate of Brucella melitensis M5-90 irr mutant was significantly lower than that of B. melitensis M5-90 under normal or iron-sufficient conditions, however, the growth rate of the B. melitensis M5-90 irr mutant was significantly higher than that of B. melitensis M5-90 under iron-limited conditions. In addition, irr mutation significantly reduced iron uptake under iron-limited conditions. Previous studies suggested that the Irr protein has multiple target genes in the Brucella genome that are involved in iron metabolism. Therefore, in the present study, a Dap-seq approach was used to investigate the other iron metabolism genes that are also regulated by the Irr protein in Brucella. A total of seven genes were identified as target genes for Irr in this study and the expression levels of these seven genes was identified using qRT-PCR. The electrophoretic mobility shift assay confirmed that six out of the seven genes, namely rirA (BME_RS13665), membrane protein (BME_RS01725), hypothetical protein (BME_RS09560), ftrA (BME_RS14525), cation-transporting P-type ATPase (zntA) (BME_RS10660), and 2Fe-2S binding protein (BME_RS13655), interact with the Irr protein. Furthermore, the iron utilization and growth assay experiments confirmed that rirA was involve in iron metabolism and growth of Brucella. In summary, our results identified six genes regulated by the Irr protein that may participate in iron metabolism, and the rirA was identified as a regulon of Irr and it also plays a role in iron metabolism of Brucella. Collectively, these results provide valuable insights for the exploration of Brucella iron metabolism.

Serum protein coating enhances the antisepsis efficacy of silver nanoparticles against multidrug-resistant Escherichia coli infections in mice.

Antimicrobial resistance poses a significant threat to public health and social development worldwide. This study aimed to investigate the effectiveness of silver nanoparticles (AgNPs) in treating multidrug-resistant bacterial infections. Eco-friendly spherical AgNPs were synthesized using rutin at room temperature. The biocompatibility of both polyvinyl pyrrolidone (PVP) and mouse serum (MS)-stabilized AgNPs was evaluated at 20 µg/mL and showed a similar distribution in mice. However, only MS-AgNPs significantly protected mice from sepsis caused by the multidrug-resistant Escherichia coli (E. coli) CQ10 strain (p = 0.039). The data revealed that MS-AgNPs facilitated the elimination of Escherichia coli (E. coli) in the blood and the spleen, and the mice experienced only a mild inflammatory response, as interleukin-6, tumor necrosis factor-α, chemokine KC, and C-reactive protein levels were significantly lower than those in the control group. The results suggest that the plasma protein corona strengthens the antibacterial effect of AgNPs in vivo and may be a potential strategy for combating antimicrobial resistance.

Single-Incision Laparoscopic Cholecystectomy Versus Standard Multiport Approach for Gallbladder Disease in Children: A Systematic Review and Meta-Analysis.

Aim: To evaluate comparative outcomes of single-incision laparoscopic cholecystectomy (SILC) and standard multiport laparoscopic cholecystectomy (SLC) in the management of children with various hematological or biliary disorders. Methods: A comprehensive systematic review of literature studies with subsequent meta-analysis of outcomes was conducted in line with preferred reporting items for systematic reviews and meta-analyses statement standards. Operative time, length of hospital stay, and postoperation complications were extracted. Results: Seven researches reporting a total number of 479 patients who underwent SILC (n = 235) or SLC (n = 244) were included. There was no difference between SILC and SLC groups in operative time (mean difference (MD) 15.14, 95% confidence interval [CI] [10.50-19.79], P = .07) and length of hospital stay (MD 0.83, 95% CI [-2.41 to 4.06], P = .62). Postoperation complications and the cost also seemed similar. Conclusions: SILC and SLC seem to have comparable effect and safety in children. Future high-quality randomized controlled trials with adequate sample sizes and long-term follow-up are required to provide stronger evidence in favor of the intervention.

[Influence of Pre-treatment Lymphocyte/Monocyte Ratio and Neutrophil/Lymphocyte Ratio on the Prognosis of Patients with Extranodal NK/T-Cell Lymphoma].

OBJECTIVE: To explore the influence of lymphocyte-to-monocyte ratio (LMR) and neutrophil-to-lymphocyte ratio (NLR) on the prognosis of patients with extranodal NK/T cell lymphoma (ENKTL). METHODS: The clinical data of 203 patients with ENKTL admitted to the First Affiliated Hospital of Zhengzhou University from January 2011 to January 2020 were retrospectively analyzed. The ROC curve determined the limit values of LMR and NLR; Categorical variables were compared using a chi-square test, expressed as frequency and percentage (n,%). Continuous variables were expressed as medians and extremes and compared with the Mann-Whitney U test; Progression-free survival (PFS) and overall survival (OS) of different grouped LMR and NLR patients were analyzed using Kaplan-Meier curves and compared with log-rank tests. The COX proportional risk regression model was used to perform one-factor and multi-factor analysis of PFS and OS. RESULTS: The optimal critical values of LMR and NLR were determined by the ROC curve, which were 2.60 and 3.40, respectively. LMR≤2.60 was more likely to occur in patients with bone marrow invasion (P=0.029) and higher LDH (P=0.036), while NLR≥3.40 was more likely to occur in patients with higher ECOG scores (P=0.002), higher LDH (P=0.008), higher blood glucose (P=0.024), and lower PLT (P=0.010). Kaplan-Meier survival analysis showed that PFS and OS of patients in the high LMR group were significantly better than the low LMR group, while PFS and OS in the low NLR group were significantly better than the high NLR group. The results of multivariate COX analysis showed that EBV-DNA positive (P=0.047), LMR≤2.60 (P=0.014), NLR≥3.40 (P=0.023) were independent risk factors affecting PFS in patients with ENKTL. LMR≤2.60 (P<0.001), NLR≥3.40 (P=0.048), and high ß2-MG (P=0.013) were independent risk factors affecting OS in patients with ENKTL. CONCLUSION: Low LMR and high NLR before treatment are associated with poor prognosis in patients with ENKTL, which also can be used as an easily testable, inexpensive, and practical prognostic indicator in the clinic.

Exosomes released by Brucella-infected macrophages inhibit the intracellular survival of Brucella by promoting the polarization of M1 macrophages.

Exosomes, membrane vesicles released extracellularly from cells, contain nucleic acids, proteins, lipids and other components, allowing the transfer of material information between cells. Recent studies reported the role of exosomes in pathogenic microbial infection and host immune mechanisms. Brucella-invasive bodies can survive in host cells for a long time and cause chronic infection, which causes tissue damage. Whether exosomes are involved in host anti-Brucella congenital immune responses has not been reported. Here, we extracted and identified exosomes secreted by Brucella melitensis M5 (Exo-M5)-infected macrophages, and performed in vivo and in vitro studies to examine the effects of exosomes carrying antigen on the polarization of macrophages and immune activation. Exo-M5 promoted the polarization of M1 macrophages, which induced the significant secretion of M1 cytokines (tumour necrosis factor-α and interferon-γ) through NF-κB signalling pathways and inhibited the secretion of M2 cytokines (IL-10), thereby inhibiting the intracellular survival of Brucella. Exo-M5 activated innate immunity and promoted the release of IgG2a antibodies that protected mice from Brucella infection and reduced the parasitaemia of Brucella in the spleen. Furthermore, Exo-M5 contained Brucella antigen components, including Omp31 and OmpA. These results demonstrated that exosomes have an important role in immune responses against Brucella, which might help elucidate the mechanisms of host immunity against Brucella infection and aid the search for Brucella biomarkers and the development of new vaccine candidates.

LDH as an adjuvant makes Brucella outer-membrane vesicles and outer-membrane vesicle-associated proteins highly protective in mice.

Objectives: Existing Brucella vaccines are attenuated and can cause vaccine-associated brucellosis; and these safety concerns have affected their application. Although subunit vaccines have the advantages of safety, efficacy, low cost, and rapid production, they are usually poorly immunogenic and insufficient to trigger persistent immunity. Therefore, we added layered double hydroxide (LDH) as an adjuvant to Brucella subunit vaccine formulations to enhance the immune response to the antigen. Materials and Methods: LDH and Freund's adjuvant were combined with Brucella outer-membrane vesicles (OMVs) and OMV-associated proteins to form a subunit vaccine, respectively. The immunogenicity of LDH as an adjuvant was assessed in BALB/c mice. We examined levels of immunoglobulin G, G1, and G2a (IgG, IgG1, and IgG2a) antibodies (aBs); percentages of Cluster of Differentiation 4-positive (CD4+) and CD8+ T cells in peripheral-blood lymphocytes; and secretion of cytokines in mouse spleen lymphocytes. Finally, splenic index and splenic bacterial load were assessed via Brucella challenge experiments on mice. Results: The LDH subunit vaccine also produced high levels of specific aBs in mice compared with Freund's adjuvant subunit vaccine and induced mainly T-helper 1 cell (Th1)-type immune responses. In addition, mice in the LDH subunit vaccine group had significantly lower bacterial loads in their spleens than those in the Freund's adjuvant subunit vaccine group, and the LDH-OMV vaccine offered a higher level of protection against Brucella attack. Conclusion: LDH as an adjuvant-paired vaccine provided a high level of protection against Brucella infection.

Corrigendum: The impact of employees' pro-environmental behaviors on corporate green innovation performance: The mediating effect of green organizational identity.

[This corrects the article DOI: 10.3389/fpsyg.2022.984856.].

Reduced macula microvascular densities may be an early indicator for diabetic peripheral neuropathy.

Purpose: To assess the alteration in the macular microvascular in type 2 diabetic patients with peripheral neuropathy (DPN) and without peripheral neuropathy (NDPN) by optical coherence tomography angiography (OCTA) and explore the correlation between retinal microvascular abnormalities and DPN disease. Methods: Twenty-seven healthy controls (42 eyes), 36 NDPN patients (62 eyes), and 27 DPN patients (40 eyes) were included. OCTA was used to image the macula in the superficial vascular complex (SVC) and deep vascular complex (DVC). In addition, a state-of-the-art deep learning method was employed to quantify the microvasculature of the two capillary plexuses in all participants using vascular length density (VLD). Results: Compared with the healthy control group, the average VLD values of patients with DPN in SVC (p = 0.010) and DVC (p = 0.011) were significantly lower. Compared with NDPN, DPN patients showed significantly reduced VLD values in the SVC (p = 0.006) and DVC (p = 0.001). Also, DPN patients showed lower VLD values (p < 0.05) in the nasal, superior, temporal and inferior sectors of the inner ring of the SVC when compared with controls; VLD values in NDPN patients were lower in the nasal section of the inner ring of SVC (p < 0.05) compared with healthy controls. VLD values in the DVC (AUC = 0.736, p < 0.001) of the DPN group showed a higher ability to discriminate microvascular damage when compared with NDPN. Conclusion: OCTA based on deep learning could be potentially used in clinical practice as a new indicator in the early diagnosis of DM with and without DPN.

Customized Reversible Stapling for Selective Delivery of Bioactive Peptides.

We have developed a new concept for reversible peptide stapling that involves macrocyclization between two amino groups and decyclization promoted via dual 1,4-elimination. Depending on the trigger moiety, this strategy could be employed to selectively deliver peptides to either intracellular or extracellular targets. As a proof of concept, a peptide inhibitor targeting a lysine-specific demethylase 1 (LSD1) was temporarily cyclized to enhance its stability and ability to cross the cell membrane. Once inside the cells, the biologically active linear peptide was released under reducing environment. Moreover, we have developed reversibly stapled peptides using antimicrobial peptides (RStAMPs) whose bioactive helical conformation can be temporarily destabilized by stapling the peptide backbone. The resulting helix-distorted RStAMPs are nontoxic and highly resistant to protease hydrolysis, while at the infection site, RStAMPs can be rapidly activated by the overproduced H2O2 through the dual 1,4-elimination. The latter restored the helical structure of the native peptide and its antimicrobial activity. This work illustrates a highly valuable macrocyclization strategy for the peptide community and should greatly benefit the field of peptide delivery.