Investigating the mechanism of rough phenotype in a naturally attenuated Brucella strain: insights from whole genome sequencing.

Objective: Brucellosis, a significant zoonotic disease, not only impacts animal health but also profoundly influences the host immune responses through gut microbiome. Our research focuses on whole genome sequencing and comparative genomic analysis of these Brucella strains to understand the mechanisms of their virulence changes that may deepen our comprehension of the host immune dysregulation. Methods: The Brucella melitensis strain CMCC55210 and its naturally attenuated variant CMCC55210a were used as models. Biochemical identification tests and in vivo experiments in mice verified the characteristics of the strain. To understand the mechanism of attenuation, we then performed de novo sequencing of these two strains. Results: We discovered notable genomic differences between the two strains, with a key single nucleotide polymorphism (SNP) mutation in the manB gene potentially altering lipopolysaccharide (LPS) structure and influencing host immunity to the pathogen. This mutation might contribute to the attenuated strain's altered impact on the host's macrophage immune response, overing insights into the mechanisms of immune dysregulation linked to intracellular survival. Furthermore, we explore that manipulating the Type I restriction-modification system in Brucella can significantly impact its genome stability with the DNA damage response, consequently affecting the host's immune system. Conclusion: This study not only contributes to understanding the complex relationship between pathogens, and the immune system but also opens avenues for innovative therapeutic interventions in inflammatory diseases driven by microbial and immune dysregulation.

Modified double-pulley fixation provides better reduction of bone fragments and union compared to single-point fixation in bony Bankart lesions.

PURPOSE: The purpose of this study was to compare clinical scores and imaging outcomes of bony Bankart lesions that underwent single-point and modified double-pulley fixation after at least 2 years of follow-up. METHODS: Patients who underwent surgery to treat bony Bankart injuries were included and divided into groups A and B. A total of 69 patients were included (32 in group A and 37 in group B). Patients in group A underwent arthroscopic modified double-pulley fixation and patients in group B underwent arthroscopic single-point fixation. Three-dimensional computed tomography (3D-CT) was used to assess glenoid reduction one day after surgery. Postoperative bony union was assessed using 3D-CT and multiplanar reconstruction images 6 months after surgery. Constant-Murley, Rowe rating system, visual analogue scale and University of California at Los Angeles and American Shoulder and Elbow Surgeons scores were recorded before and after surgery. RESULTS: In terms of imaging measurements, there was no significant group difference in the preoperative size of the glenoid defect, the size of the bony fragment or the expected postoperative size of the glenoid defect. The sizes of the actual postoperative glenoid defects differed significantly between the groups (p = 0.027), as did the absolute difference between the expected and actual glenoid defect sizes (p < 0.001). At 6 months postoperatively, 50.0% of group A patients and 24.3% of group B patients exhibited complete bony union (p = 0.027); the rates of partial union were 37.5% and 56.8%, respectively. At the final follow-up, all clinical scores were significantly better than the preoperative scores (all p < 0.05), with no significant group differences (not significant). CONCLUSIONS: The use of the modified double-pulley technique with two anchors to treat bony Bankart injuries provides a better reduction of bone fragments than single-point fixation with two anchors and was associated with a higher rate of early bone union. LEVEL OF EVIDENCE: Level III.

Mycobacterium tuberculosis produces D-serine under hypoxia to limit CD8+ T cell-dependent immunity in mice.

Adaptation to hypoxia is a major challenge for the survival of Mycobacterium tuberculosis (Mtb) in vivo. Interferon (IFN)-γ-producing CD8+ T cells contribute to control of Mtb infection, in part by promoting antimicrobial activities of macrophages. Whether Mtb counters these responses, particularly during hypoxic conditions, remains unknown. Using metabolomic, proteomic and genetic approaches, here we show that Mtb induced Rv0884c (SerC), an Mtb phosphoserine aminotransferase, to produce D-serine. This activity increased Mtb pathogenesis in mice but did not directly affect intramacrophage Mtb survival. Instead, D-serine inhibited IFN-γ production by CD8+ T cells, which indirectly reduced the ability of macrophages to restrict Mtb upon co-culture. Mechanistically, D-serine interacted with WDR24 and inhibited mTORC1 activation in CD8+ T cells. This decreased T-bet expression and reduced IFN-γ production by CD8+ T cells. Our findings suggest an Mtb evasion mechanism where pathogen metabolic adaptation to hypoxia leads to amino acid-dependent suppression of adaptive anti-TB immunity.

Mycobacterial biotin synthases require an auxiliary protein to convert dethiobiotin into biotin.

Lipid biosynthesis in the pathogen Mycobacterium tuberculosis depends on biotin for posttranslational modification of key enzymes. However, the mycobacterial biotin synthetic pathway is not fully understood. Here, we show that rv1590, a gene of previously unknown function, is required by M. tuberculosis to synthesize biotin. Chemical-generic interaction experiments mapped the function of rv1590 to the conversion of dethiobiotin to biotin, which is catalyzed by biotin synthases (BioB). Biochemical studies confirmed that in contrast to BioB of Escherichia coli, BioB of M. tuberculosis requires Rv1590 (which we named "biotin synthase auxiliary protein" or BsaP), for activity. We found homologs of bsaP associated with bioB in many actinobacterial genomes, and confirmed that BioB of Mycobacterium smegmatis also requires BsaP. Structural comparisons of BsaP-associated biotin synthases with BsaP-independent biotin synthases suggest that the need for BsaP is determined by the [2Fe-2S] cluster that inserts sulfur into dethiobiotin. Our findings open new opportunities to seek BioB inhibitors to treat infections with M. tuberculosis and other pathogens.

Ginseng-DF ameliorates intestinal mucosal barrier injury and enhances immunity in immunosuppressed mice by regulating MAPK/NF-κB signaling pathways.

PURPOSE: Dietary fiber (DF) has a good application prospect in effectively restoring the integrity of the intestinal mucosal barrier. Ginseng-DF has good physicochemical properties and physiological activity and shows positive effects in enhancing immunity. The aim of this study was to investigate the protective effect of Ginseng-DF on intestinal mucosal barrier injury induced by cyclophosphamide (CTX) in immunosuppressed mice and its possible mechanism. METHODS: The effects of Gginseng-DF on immune function in mice were studied by delayed-type hypersensitivy, lymphocyte proliferation assay and NK cytotoxicity assay, the T lymphocyte differentiation and intestinal barrier integrity were analyzed by flow cytometry and western blot. RESULTS: Ginseng-DF (2.5% and 5%) could attenuate the inhibition of DTH response by CTX, promote the transformation and proliferation of lymphocytes, and stimulate NK effector cell activity. At the same time, Ginseng-DF could restore the proportion of CD4+/CD8+ T lymphocytes induced by CTX to different extents, improved spleen tissue damage, promoted the secretion of immunoglobulin IgG, and enhanced body immunity. More importantly, Ginseng-DF could up-regulate the contents of TNF-α, IFN-γ, IL-6 and IL-1ß in serum and intestine of immunosuppressed mice to maintain the balance between Th1/Th2 cytokines, and improve the permeability of intestinal mucosal barrier. Meanwhile, Ginseng-DF could reduce intestinal epithelial cell apoptosis and improve intestinal adaptive immunity in CTX-induced immunosuppressed mice by regulating MAPK/NF-κB signaling pathway. CONCLUSION: Ginseng-DF can be used as a safe dietary supplement to enhance body immunity and reduce intestinal mucosal injury caused by CTX.

Effects of whole nutritional formula foods on nutritional improvement and intestinal flora in malnourished rats.

Food for special medical purposes (FSMP) has received increasing attention as an enteral nutritional supplement. To investigate the effects of whole nutritional formula (WNF) containing dietary fiber and regular formula on nutritional supplementation and improvement of intestinal microecology, a rat malnutrition model was established with the formulations of WNF, FOS, and SDF (10, 20 g/kg bw) administered by gavage for 30 days. The results showed that the three formulations effectively improved the nutritional status of the malnourished rats, significantly increasing the level of IgG, increasing the abundance of Bacteroidetes, and affecting the content of propionic acid (PRO). The nutritional status of rats is closely related to growth performance, nutritional indexes, and immunoglobulin index, which cause changes in the composition of the intestinal flora. The above results showed that WNF positively affected the nutritional improvement, immune level, and intestinal health of rats. The comprehensive evaluation also suggested that the formulation containing ginseng water-soluble dietary fiber (ginseng-SDF) had the most significant effect.

Ginsenoside Rg5 Activates the LKB1/AMPK/mTOR Signaling Pathway and Modifies the Gut Microbiota to Alleviate Nonalcoholic Fatty Liver Disease Induced by a High-Fat Diet.

The primary objective of this investigation was to elucidate the manner in which ginsenoside Rg5 (Rg5) ameliorates nonalcoholic fatty liver disease (NAFLD) via the modulation of the gut microbiota milieu. We administered either a standard diet (ND) or a high-fat diet (HFD), coupled with 12-week treatment employing two distinct doses of Rg5 (50 and 100 mg/kg/d), to male C57BL/6J mice. In comparison to the HFD cohort, the Rg5-treated group demonstrated significant enhancements in biochemical parameters, exemplified by a substantial decrease in lipid concentrations, as well as the reduced expression of markers indicative of oxidative stress and liver injury. This signifies a mitigation of hepatic dysfunction induced by an HFD. Simultaneously, Rg5 demonstrates the capacity to activate the LKB1/AMPK/mTOR signaling pathway, instigating energy metabolism and consequently hindering the progression of NAFLD. Furthermore, we underscored the role of Rg5 in the treatment of NAFLD within the gut-microbiota-liver axis. Analysis via 16S rRNA sequencing unveiled that Rg5 intervention induced alterations in gut microbiota composition, fostering an increase in beneficial bacteria, such as Bacteroides and Akkermansia, while concurrently reducing the relative abundance of detrimental bacteria, exemplified by Olsenella. Furthermore, employing fecal microbiota transplantation (FMT) experiments, we observed analogous outcomes in mice subjected to fecal bacterial transplants, providing additional verification of the capacity of Rg5 to mitigate NAFLD in mice by actively participating in the restoration of gut microbiota via FMT. Drawing from these data, the regulation of the gut microbiota is recognized as an innovative strategy for treating or preventing NAFLD and metabolic syndrome. Consequently, these research findings suggest that Rg5 holds promise as a potential therapeutic agent for NAFLD management.

The Staphylococcus aureus ArlS Kinase Inhibitor Tilmicosin Has Potent Anti-Biofilm Activity in Both Static and Flow Conditions.

Staphylococcus aureus can form biofilms on biotic surfaces or implanted materials, leading to biofilm-associated diseases in humans and animals that are refractory to conventional antibiotic treatment. Recent studies indicate that the unique ArlRS regulatory system in S. aureus is a promising target for screening inhibitors that may eradicate formed biofilms, retard virulence and break antimicrobial resistance. In this study, by screening in the library of FDA-approved drugs, tilmicosin was found to inhibit ArlS histidine kinase activity (IC50 = 1.09 µM). By constructing a promoter-fluorescence reporter system, we found that tilmicosin at a concentration of 0.75 µM or 1.5 µM displayed strong inhibition on the expression of the ArlRS regulon genes spx and mgrA in the S. aureus USA300 strain. Microplate assay and confocal laser scanning microscopy showed that tilmicosin at a sub-minimal inhibitory concentration (MIC) had a potent inhibitory effect on biofilms formed by multiple S. aureus strains and a strong biofilm-forming strain of S. epidermidis. In addition, tilmicosin at three-fold of MIC disrupted USA300 mature biofilms and had a strong bactericidal effect on embedded bacteria. Furthermore, in a BioFlux flow biofilm assay, tilmicosin showed potent anti-biofilm activity and synergized with oxacillin against USA300.

[Comparison of intraoperative effects of computer navigation-assisted and simple arthroscopic reconstruction of posterior cruciate ligament tibial tunnel].

Objective: To compare the intraoperative effects of computer navigation-assisted versus simple arthroscopic reconstruction of posterior cruciate ligament (PCL) tibial tunnel. Methods: The clinical data of 73 patients with PCL tears who were admitted between June 2021 and June 2022 and met the selection criteria were retrospectively analysed, of whom 34 cases underwent PCL tibial tunnel reconstruction with navigation-assisted arthroscopy (navigation group) and 39 cases underwent PCL tibial tunnel reconstruction with arthroscopy alone (control group). There was no significant difference in baseline data between the two groups, including gender, age, body mass index, side of injury, time from injury to surgery, preoperative posterior drawer test, knee range of motion (ROM), Tegner score, Lysholm score, and International Knee Documentation Committee (IKDC) score between the two groups ( P>0.05). The perioperative indicators (operation time and number of guide wire drillings) were recorded and compared between the two groups. The angle between the graft and the tibial tunnel and the exit positions of the tibial tunnel in the coronal, sagittal, and transverse planes respectively were measured on MRI at 1 day after operation. The knee ROM, Tegner score, Lysholm score, and IKDC score were evaluated before operation and at last follow-up. Results: The operation time in the navigation group was shorter than that in the control group, and the number of intraoperative guide wire drillings was less than that in the control group, the differences were significant ( P<0.05). Patients in both groups were followed up 12-17 months, with an average of 12.8 months. There was no perioperative complications such as vascular and nerve damage, deep venous thrombosis and infection of lower extremity. During the follow-up, there was no re-injuries in either group and no revision was required. The results showed that there was no significant difference in the exit positions of the tibial tunnel in the coronal, sagittal, and transverse planes between the two groups ( P>0.05), but the angle between the graft and the tibial tunnel was significantly greater in the navigation group than in the control group ( P<0.05). At last follow-up, 30, 3, 1 and 0 cases were rated as negative, 1+, 2+, and 3+ of posterior drawer test in the navigation group and 33, 5, 1, and 0 cases in the control group, respectively, which significantly improved when compared with the preoperative values ( P<0.05), but there was no significant difference between the two groups ( P>0.05). At last follow-up, ROM, Tegner score, Lysholm score, and IKDC score of the knee joint significantly improved in both groups when compared with preoperative values ( P<0.05), but there was no significant difference in the difference in preoperative and postoperative indicators between the two groups ( P>0.05). Conclusion: Computer-navigated arthroscopic PCL tibial tunnel reconstruction can quickly and accurately prepare tunnels with good location and orientation, with postoperative functional scores comparable to arthroscopic PCL tibial tunnel reconstruction alone.

[Experimental study of M2 microglia transplantation promoting spinal cord injury repair in mice].

Objective: To investigate the effect of M2 microglia (M2-MG) transplantation on spinal cord injury (SCI) repair in mice. Methods: Primary MG were obtained from the cerebral cortex of 15 C57BL/6 mice born 2-3 days old by pancreatic enzyme digestion and identified by immunofluorescence staining of Iba1. Then the primary MG were co-cultured with interleukin 4 for 48 hours (experimental group) to induce into M2 phenotype and identified by immunofluorescence staining of Arginase 1 (Arg-1) and Iba1. The normal MG were harvested as control (control group). The dorsal root ganglion (DRG) of 5 C57BL/6 mice born 1 week old were co-cultured with M2-MG for 5 days to observe the axon length, the DRG alone was used as control. Forty-two 6-week-old female C57BL/6 mice were randomly divided into sham group ( n=6), SCI group ( n=18), and SCI+M2-MG group ( n=18). In sham group, only the laminae of T 10 level were removed; SCI group and SCI+M2-MG group underwent SCI modeling, and SCI+M2-MG group was simultaneously injected with M2-MG. The survival of mice in each group was observed after operation. At immediate (0), 3, 7, 14, 21, and 28 days after operation, the motor function of mice was evaluated by Basso Mouse Scale (BMS) score, and the gait was evaluated by footprint experiment at 28 days. The spinal cord tissue was taken after operation for immunofluorescence staining, in which glial fibrillary acidic protein (GFAP) staining at 7, 14, and 28 days was used to observe the injured area of the spinal cord, neuronal nuclei antigen staining at 28 days was used to observe the survival of neurons, and GFAP/C3 double staining at 7 and 14 days was used to observe the changes in the number of A1 astrocytes. Results: The purity of MG in vitro reached 90%, and the most of the cells were polarized into M2 phenotype identified by Arg-1 immunofluorescence staining. M2-MG promoted the axon growth when co-cultured with DRGs in vitro ( P<0.05). All groups of mice survived until the experiment was completed. The hind limb motor function of SCI group and SCI+M2-MG group gradually recovered over time. Among them, the SCI+M2-MG group had significantly higher BMS scores than the SCI group at 21 and 28 days ( P<0.05), and the dragging gait significantly improved at 28 days, but it did not reach the level of the sham group. Immunofluorescence staining showed that compared with the SCI group, the SCI+M2-MG group had a smaller injury area at 7, 14, and 28 days, an increase in neuronal survival at 28 days, and a decrease in the number of A1 astrocytes at 7 and 14 days, with significant differences ( P<0.05). Conclusion: M2-MG transplantation improves the motor function of the hind limbs of SCI mice by promoting neuron survival and axon regeneration. This neuroprotective effect is related to the inhibition of A1 astrocytes polarization.

M2 Microglia-derived Exosomes Promote Spinal Cord Injury Recovery in Mice by Alleviating A1 Astrocyte Activation.

M2 microglia transplantation has previously demonstrated beneficial effects on spinal cord injury (SCI) by regulating neuroinflammation and enhancing neuronal survival. Exosomes (EXOs), secreted by almost all cell types, embody partial functions and properties of their parent cells. However, the effect of M2 microglia-derived EXOs (M2-EXOs) on SCI recovery and the underlying molecular mechanisms remain unclear. In this study, we isolated M2-EXOs and intravenously introduced them into mice with SCI. Considering the reciprocal communication between microglia and astroglia in both healthy and injured central nervous systems (CNSs), we subsequently focused on the influence of M2-EXOs on astrocyte phenotype regulation. Our findings indicated that M2-EXOs promoted neuron survival and axon preservation, reduced the lesion area, inhibited A1 astrocyte activation, and improved motor function recovery in SCI mice. Moreover, they inhibited the nuclear translocation of p65 and the activation of the NF-κB signalling pathway in A1 astrocytes. Therefore, our research suggests that M2-EXOs mitigate the activation of neurotoxic A1 astrocytes by inhibiting the NF-κB signalling pathway, thereby improving spinal tissue preservation and motor function recovery following SCI. This positions M2-EXOs as a promising therapeutic strategy for SCI.

Antimicrobial and anti-biofilm activity of a thiazolidinone derivative against Staphylococcus aureus in vitro and in vivo.

Staphylococcus aureus (S. aureus) causes many infections with significant morbidity and mortality. S. aureus can form biofilms, which can cause biofilm-associated diseases and increase resistance to many conventional antibiotics, resulting in chronic infection. It is critical to develop novel antibiotics against staphylococcal infections, particularly those that can kill cells embedded in biofilms. This study aimed to investigate the bacteriocidal and anti-biofilm activities of thiazolidinone derivative (TD-H2-A) against S. aureus. A total of 40 non-duplicate strains were collected, and the minimum inhibitory concentrations (MICs) of TD-H2-A were determined. The effect of TD-H2-A on established S. aureus mature biofilms was examined using a confocal laser scanning microscope (CLSM). The antibacterial effects of the compound on planktonic bacteria and bacteria in mature biofilms were investigated. Other characteristics, such as cytotoxicity and hemolytic activity, were researched. A mouse skin infection model was used, and a routine hematoxylin and eosin (H&E) staining was used for histological examination. The MIC values of TD-H2-A against the different S. aureus strains were 6.3-25.0 µg/mL. The 5 × MIC TD-H2-A killed almost all planktonic S. aureus USA300. The derivative was found to have strong bacteriocidal activity against cells in mature biofilms meanwhile having low cytotoxicity and hemolytic activity against Vero cells and human erythrocytes. TD-H2-A had a good bacteriocidal effect on S. aureus SA113-infected mice. In conclusion, TD-H2-A demonstrated good bacteriocidal and anti-biofilm activities against S. aureus, paving the way for the development of novel agents to combat biofilm infections and multidrug-resistant staphylococcal infections.IMPORTANCEStaphylococcus aureus, a notorious pathogen, can form a stubborn biofilm and develop drug resistance. It is crucial to develop new anti-infective therapies against biofilm-associated infections. The manuscript describes the new antibiotic to effectively combat multidrug-resistant and biofilm-associated diseases.

Uptake and accumulation of di(2-ethylhexyl) phthalate (DEHP) in a soil-ginseng system and toxicological mechanisms on ginseng (Panax ginseng C.A. Meyer).

Di(2-ethylhexyl) phthalate (DEHP) is regarded as a priority environmental pollutant. This study explored the adsorption and accumulation of DEHP within the ginseng-soil system and the mechanism of DEHP toxicity to ginseng (Panax ginseng C.A. Meyer). Under exposure to 22.10 mg/kg DEHP in soil, DEHP mainly accumulated in ginseng leaves (20.28 mg/kg), stems (4.84 mg/kg) and roots (2.00 mg/kg) after 42 days. The oxidative damage, metabolism, protein express of ginseng were comprehensively measured and analyzed. The results revealed that MDA presented an activation trend in ginseng stems and leaves after 42 days of DEHP exposure, while the opposite trend was observed for POD. Levels of ginsenoside metabolites Rg2, Rg3, Rg5, Rd, Rf and CK decreased in the ginseng rhizosphere exudates under DEHP stress. Further investigations revealed that DEHP disrupts ginsenoside synthesis by inducing glycosyltransferase (GS) and squalene synthase (SS) protein interactions. Molecular docking indicated that DEHP could stably bind to GS and SS by intermolecular forces. These findings provide new information on the ecotoxicological effect of DEHP on ginseng root.

Profibrogenic macrophage-targeted delivery of mitochondrial protector via exosome formula for alleviating pulmonary fibrosis.

Pulmonary fibrosis (PF) is a devastating lung disease with limited treatment options. During this pathological process, the profibrogenic macrophage subpopulation plays a crucial role, making the characterization of this subpopulation fundamentally important. The present study revealed a positive correlation between pulmonary macrophages with higher mitochondrial mass (Mømitohigh) and fibrosis. Among the Mømitohigh subpopulation of CD206+ M2, characterized by higher expression of dynamin 1-like (Drp1), as determined by flow cytometry and RNA-seq analysis, a therapeutic intervention was developed using an exosome-based formula composed of pathfinder and therapeutics. A pathfinder exosome called "exosomeMMP19 (ExoMMP19)", was constructed to display matrix metalloproteinase-19 (MMP19) on the surface to locally break down the excessive extracellular matrix (ECM) in the fibrotic lung. A therapeutic exosome called "exosome therapeutics (ExoTx)", was engineered to display D-mannose on the surface while encapsulating siDrp1 inside. Prior delivery of ExoMMP19 degraded excessive ECM and thus paved the way for ExoTx to be delivered into Mømitohigh, where ExoTx inhibited mitochondrial fission and alleviated PF. This study has not only identified Mømitohigh as profibrotic macrophages but it has also provided a potent strategy to reverse PF via a combination of formulated exosomes.

Mycobacterium tuberculosis suppresses host DNA repair to boost its intracellular survival.

Mycobacterium tuberculosis (Mtb) triggers distinct changes in macrophages, resulting in the formation of lipid droplets that serve as a nutrient source. We discover that Mtb promotes lipid droplets by inhibiting DNA repair responses, resulting in the activation of the type-I IFN pathway and scavenger receptor-A1 (SR-A1)-mediated lipid droplet formation. Bacterial urease C (UreC, Rv1850) inhibits host DNA repair by interacting with RuvB-like protein 2 (RUVBL2) and impeding the formation of the RUVBL1-RUVBL2-RAD51 DNA repair complex. The suppression of this repair pathway increases the abundance of micronuclei that trigger the cyclic GMP-AMP synthase (cGAS)/stimulator of interferon genes (STING) pathway and subsequent interferon-ß (IFN-ß) production. UreC-mediated activation of the IFN-ß pathway upregulates the expression of SR-A1 to form lipid droplets that facilitate Mtb replication. UreC inhibition via a urease inhibitor impaired Mtb growth within macrophages and in vivo. Thus, our findings identify mechanisms by which Mtb triggers a cascade of cellular events that establish a nutrient-rich replicative niche.

The dose response of erythemal area and intensity on the unprotected skin fits well to a logistic 3P model in SPF tests of a Chinese population, which has the potential to improve the precision and consistency of minimal erythema dose determination.

BACKGROUND: The current ISO guidelines for minimal erythema dose (MED) determination require assessment of erythema area of UV-irradiated skin sites. However, this parameter has not been adequately quantified in daily practice. The aims of this study were to investigate the dose response on the unprotected skin sites by quantifying the erythema area and intensity and to show the potential for improving the precision and consistency of MEDu determination by developing predictive models. METHODS: Standard radiation tests were conducted on the back of 31 healthy Chinese volunteers and the MEDu site of each subject was clinically determined by dermatologists. Images of test sites were captured 24 h after radiation, and the erythema area (%EA) and intensity (∆a*) were measured by image analysis. The data were fitted to a logistic 3P function to obtain dose-response curves, and a set of logit (inverse-logistic) models were then derived. An erythema area threshold of %EA = 52% was established to predict MEDu based on the clinical endpoints defined by ISO 24444:2019. RESULTS: Analysis of the clinically determined MEDu sites revealed wide ranges of %EA (62.3 ± 15% SD) and ∆a* (2.96 ± 0.92 SD). The dose response fitted well to a logistic 3P model (mean R2 = 0.965 and 0.975 for %EA and ∆a*, respectively). Applying the area threshold, values of MEDu were determined by the logit model for the test population, which significantly improved the consistency of MEDu determination (52 ± 0% SD and 2.73 ± 0.61 SD for %EA and ∆a*, respectively). CONCLUSION: This study demonstrated that the dose response of UV-induced erythema can be quantified and modeled once the erythema area and intensity are measured. The results of this study show the potential to improve the precision and consistency of MEDu determination in an SPF test. The similar potential in photodermatological, therapeutic, and diagnostic applications was also implied.

Postoperative pathological complete response in a patient with PD­L1­negative stage IIIB lung squamous cell carcinoma following neoadjuvant tislelizumab treatment combined with chemotherapy: A case report and literature review.

The utilization of immune checkpoint inhibitors in oncological treatment has increased in recent years. The therapeutic strategy of targeting the programmed death-1 (PD-1)/programmed death-ligand 1 (PD-L1) pathway has altered the management of advanced non-small cell lung carcinoma (NSCLC). Tislelizumab, a novel anti-PD-1 monoclonal antibody developed in China, has demonstrated efficacy in treating advanced NSCLC. However, its potential role as a neoadjuvant therapy for locally advanced NSCLC has not been definitively established. Current guidelines do not specify which patient populations may gain the most benefit from neoadjuvant immunotherapy coupled with chemotherapy, nor do they indicate the optimal timing, dose or duration of adjuvant maintenance therapy post-NSCLC surgery. Similarly, data concerning the safety and practicability of surgical resection following neoadjuvant tislelizumab treatment for NSCLC remain limited. The present study describes the case of a patient diagnosed with stage IIIB NSCLC, which was initially deemed unresectable. A preoperative biopsy of the tumor mass revealed squamous cell carcinoma and a negative PD-L1 gene test. Notably, after two cycles of neoadjuvant tislelizumab treatment coupled with chemotherapy, the tumor exhibited marked shrinkage. This permitted the patient to undergo thoracoscopic radical lung cancer resection, which resulted in a pathological complete response. Postoperative pathology identified a large infiltration of lymphoplasmacytic cells and foamy histiocytes. The patient experienced grade 2 myelosuppression, a condition that was successfully addressed with the administration of recombinant human granulocyte colony-stimulating factor. The present case indicates the safety and feasibility of neoadjuvant immunotherapy integrated with chemotherapy for patients with locally advanced, PD-L1-negative NSCLC prior to surgical intervention. Moreover, the case suggests the potential of this therapeutic combination to alter the tumor microenvironment. However, the generalization of these findings necessitates further validation through randomized multicenter trials.

Identification and Validation of Ferroptosis-Related Genes in Patients with Acute Spinal Cord Injury.

Ferroptosis plays crucial roles in the pathology of spinal cord injury (SCI). The purpose of this study was to identify differentially expressed ferroptosis-related genes (DE-FRGs) in human acute SCI by bioinformatics analysis and validate the hub DE-FRGs in non-SCI and SCI patients. The GSE151371 dataset was downloaded from the Gene Expression Omnibus and difference analysis was performed. The differentially expressed genes (DEGs) in GSE151371 overlapped with the ferroptosis-related genes (FRGs) obtained from the Ferroptosis Database. A total of 41 DE-FRGs were detected in 38 SCI samples and 10 healthy samples in GSE151371. Then, enrichment analyses of these DE-FRGs were performed for functional annotation. The GO enrichment results showed that upregulated DE-FRGs were mainly associated with reactive oxygen species and redox reactions, and the KEGG enrichment analysis indicated involvement in some diseases and ferroptosis pathways. Protein-protein interaction (PPI) analysis and lncRNA-miRNA-mRNA regulatory network were performed to explore the correlations between genes and regulatory mechanisms. The relationship between DE-FRGs and differentially expressed mitochondria-related genes (DE-MRGs) was also analyzed. Finally, quantitative real-time polymerase chain reaction (qRT-PCR) was used to verify the hub DE-FRGs in clinical blood samples from acute SCI patients and healthy controls. Consistent with the bioinformatics results, qRT-PCR of the clinical samples indicated similar expression levels of TLR4, STAT3, and HMOX1. This study identified DE-FRGs in blood samples from SCI patients, and the results could improve our understanding of the molecular mechanisms of ferroptosis in SCI. These candidate genes and pathways could be therapeutic targets for SCI.

A Novel Process for One-Step Separation and Cyclodextrin Inclusion of Ginsenoside Rg5 from Ginseng Stem-Leaf Saponins (GSLS): Preparation, Characterization, and Evaluation of Storage Stability and Bioactivity.

BACKGROUND: Ginsenoside Rg5 has been proven to possess numerous health benefits. However, Rg5 is difficult to prepare using the current methods, and the poor stability and solubility of Rg5 are intractable properties that limit its application. We try to establish and optimize a new method for preparing Rg5. METHODS: Different amino acids acted as catalysts, and reaction conditions were investigated to transform Rg5 in GSLS. Different CDs and reaction conditions were investigated for the preparation of CD-Rg5 based on yield and purity; ESI-MS, FT-IR, XRD and SEM analyses were used to prove the formation of the CD-Rg5 inclusion complex. Both the stability and bioactivity of ß-CD-Rg5 were investigated. RESULTS: The content of Rg5 reached 140.8 mg/g after transformation of GSLS using Asp as a catalyst. The yield of ß-CD-Rg5 reached a maximum of 12% and a purity of 92.5%. The results showed that the ß-CD-Rg5 inclusion complex can improve its stability of Rg5 against light and temperature. Antioxidant activity analyses against DPPH, ABTS+, and Fe2+ chelation showed enhanced antioxidant activity of the ß-CD-Rg5 inclusion complex. CONCLUSIONS: A novel and effective strategy for the separation of Rg5 from ginseng stem-leaf saponins (GSLS) was developed to improve the stability, solubility, and bioactivity of Rg5.

Mutation of gdpS gene induces a viable but non-culturable state in Staphylococcus epidermidis and changes in the global transcriptional profile.

BACKGROUND: In the genome of staphylococci, only the gdpS gene encodes the conserved GGDEF domain, which is the characteristic of diguanylate cyclases. In our previous study, we have demonstrated that the gdpS gene can modulate biofilm formation by positively regulating the expression of ica operon in Staphylococcus epidermidis. Moreover, this regulation seems to be independent of the c-di-GMP signaling pathway and the protein-coding function of this gene. Therefore, the biological function of the gdpS gene remains to be further investigated. RESULTS: In the present study, it was observed that mutation of the gdpS gene induced S. epidermidis to enter into a presumed viable but nonculturable state (VBNC) after cryopreservation with glycerol. Similarly, when moved from liquid to solid culture medium, the gdpS mutant strain also exhibited a VBNC state. Compared with the wild-type strain, the gdpS mutant strain autolyzed more quickly during storage at 4℃, indicating its increased susceptibility to low temperature. Transcriptional profiling analysis showed that the gdpS mutation affected the transcription of 188 genes (92 genes were upregulated and 96 genes were downregulated). Specifically, genes responsible for glycerol metabolism were most markedly upregulated and most of the altered genes in the mutant strain are those involved in nitrogen metabolism. In addition, the most significantly downregulated genes included the betB gene, whose product catalyzes the synthesis of glycine betaine and confers tolerance to cold. CONCLUSION: The preliminary results suggest that the gdpS gene may participate in VBNC formation of S. epidermidis in face of adverse environmental factors, which is probably achieved by regulating expression of energy metabolism genes. Besides, the gdpS gene is critical for S. epidermidis to survive low temperature, and the underlying mechanism may be partly explained by its influence on expression of betB gene.