ObjectiveThis study aimed to elucidate the mechanistic role of Staphylococcus aureus in the pathogenesis of atopic dermatitis (AD), a chronic inflammatory skin disorder characterized by pruritus and barrier dysfunction. A key focus was screening traditional Chinese medicine (TCM) active components with dual antibacterial and antipruritic efficacy, followed by systematic evaluation of their in vitro antibacterial activity. Additionally, a novel drug delivery system was constructed to enable localized efficient drug delivery, inhibiting S. aureus proliferation and alleviating its induced pruritus, thereby providing new strategies for targeted AD therapy. MethodsMale C57BL/6J mice aged 6-8 weeks (body weight 18-22 g) were used to establish an AD model via repeated oxazolone sensitization. On day 14, microbial samples were collected from the lesional area (1 cm²) using sterile cotton swabs, followed by vortex mixing, serial dilution, and plating on 5% sheep blood agar plates (incubated at 37°C for 24 h). Single colonies with complete transparent β-hemolytic zones were isolated and identified as vancomycin-intermediate S. aureus (VISA) via 16S rRNA sequencing. An S. aureus mono-infection animal model was then established by applying gauze saturated with bacterial suspension (McFarland turbidity 0.1) to the nape and back skin of mice. The pruritic phenotype and inflammatory cell infiltration induced by S. aureus were evaluated using comprehensive approaches including behavioral assays (e.g., scratching frequency recording), hematoxylin-eosin (HE) staining, and toluidine blue staining. The in vitro antibacterial efficacy of the TCM monomer pseudolaric acid B (PAB) and double network hydrogel (DN) was separately assessed by disk diffusion assay, while the minimum inhibitory concentration (MIC) of PAB was determined via broth dilution method. Further validation of the pharmacodynamic characteristics of the composite system (PAB@DN, composed of PAB and DN) was conducted through behavioral assays, HE staining, and dermatitis scoring, with its drug release profile evaluated by mass spectrometry analysis. Based on scratching behavioral analysis and dermatitis scoring, the optimal ratio and concentration of PAB@DN were optimized. ResultsThe S. aureus load in AD lesional tissues was significantly higher than in normal skin ((5.3±0.33)×10⁶ CFU vs. (3.6±0.26)×10⁷ CFU, P<0.001). In the S. aureus mono-infection group, mice exhibited a 6.7-fold increase in scratching frequency compared to the control group. HE staining revealed marked epidermal thickening ((10.4±2.39) μm vs. (85.6±1.95) μm, P<0.000 1), and toluidine blue staining showed a 23-fold increase in mast cell degranulation. Pseudolaric acid B exhibited a significant concentration-dependent inhibitory effect onS. aureus growth, with its in vitro antibacterial effect being 57% that of the antibiotic cefepime (inhibition zone diameter: PAB (1.885±0.036) cm vs. cefepime (3.636±0.005) cm, P<0.000 1) and a minimum inhibitory concentration (MIC) of 1 g/L. The carrier double network hydrogel (DN) itself lacked direct antibacterial activity (no significant difference in inhibition zone diameter compared to the control) but effectively ameliorated the dry symptoms of AD-like lesions. The PAB@DN composite system demonstrated a synergistic effect compared to individual components, resulting in a 50% reduction in scratching behavior, an 86% decrease in dermatitis score, and a 60% reduction in epidermal thickening. It also reduced the S. aureus load in mouse skin by approximately 34%, with the optimal effective formulation being PAB at 1 g/L loaded onto DN. ConclusionS. aureus colonization plays a critical driving role in the onset and progression of AD. Using an S. aureus infection model, this study confirmed that the pseudolaric acidB-hydrogel composite delivery system (PAB@DN) can effectively alleviate S. aureus-induced pruritus and skin damage, providing experimental evidence for microbiota-targeted therapy of AD.

The concept of "qi deficiency with stagnation" refers to a pathological state characterized by the depletion of primordial qi， impaired qi transformation， and the development of internal stagnation. Under the cyclic chemotherapy regimen in oncology， chemotherapy-induced myelosuppression follows a progressive pathological course from qi deficiency to increasing stagnation. This sequential evolution from mild to severe myelosuppression closely aligns with the dynamic syndrome differentiation and treatment framework of "qi deficiency with stagnation". "Qi deficiency" reflects the gradual depletion of qi， blood， and essence， while "stagnation" refers to the accumulation of phlegm， turbid dampness， and blood stasis. These two components interact reciprocally， forming a vicious cycle where deficiency leads to stagnation， and stagnation further damages the healthy qi. In the early stage of mild myelosuppression， chemotoxicity begins to accumulate in the bone marrow， leading to qi consumption， blood deficiency， yin injury， and the gradual formation of turbid phlegm and damp stagnation. In the advanced stage of severe myelosuppression， the accumulation of toxicity causes qi sinking， exhaustion of essence， and marrow depletion， along with blood stasis obstructing the collaterals. Treatment strategies should be based on syndrome differentiation， with an emphasis on assessing the severity of the condition， balancing deficiency and excess， and achieving both symptomatic relief and root cause resolution.

Objective To elucidate the correlation between specific nucleocapsid(N)protein mutant of the SARS-CoV-2 B.1.1.7 variant and clinical stratification in COVID-19 patients,revealing their impact on N protein liquid-liquid phase separation(LLPS)and host innate immune response.Methods Based on whole-genome sequencing data of the SARS-CoV-2 B.1.1.7 lineage from the GISAID database,non-synonymous mutation sites significantly associated with mild/severe clinical phenotypes were screened.For high-frequency N protein mutant,IFN-β promoter transcriptional activity was quantitatively measured using a dual-luciferase reporter system.qPCR was used to detect the mRNA expression levels of interferon(IFN)-β,interleukin(IL)-6 and tumor necrosis factor(TNF)-α.LLPS characteristics were observed by confocal microscopy.The ubiquitination status of host MAVS was detected by Western blot assay.Results A total of 17 640 non-synonymous mutation sites were identified,among which 65 were associated with mild cases and 20 were related to severe cases,with a mutation frequency>1%.The N protein mutation sites associated with severe cases were D3L,M234I and R203K-G204R-T205I.N protein and the mutants NM234I,NR203K-G204R-T205I inhibited the promoter activity of IFN-β(P＜0.05).Compared to the wild type N protein,NR203K-G204R-T205I mutation significantly reduced the mRNA levels of IFN-β,IL-6 and TNF-α(P＜0.05),and altered the phase separation state by dispersing the formation of LLPS condensates.However,N mutant did not affect the ubiquitination modification of host MAVS.Conclusion N protein mutants of the SARS-CoV-2 B.1.1.7 variant can influence the clinical prognosis of COVID-19 patients by altering LLPS status and suppressing the innate immune responses.These finding provides a theoretical basis for the design of antiviral drugs targeting the N protein.

AIM To study the chemical constituents from Tylophora ovata(Lindl.)Hook.ex Steud.and their antibacterial activities.METHODS Ethanol extract was isolated and purified by MCI,silica gel,Sephadex LH-20 and semi-preparative HPLC,then the structures of obtained compounds were identified by spectral data.The inhibitory activities of each compound against Phomopsis sp.were determined by mycelial growth rate method.RESULTS Twenty-six compounds were identified as paeonol(1),stigmast-4-en-3-one(2),ergosta-4,6,8(14),22-tetraen-3-one(3),2,4-methoxyphenol(4),1,2,4-trimethoxybenzene(5),3-methoxyphenol(6),3,4-dimethoxyacetophenone(7),5α,8α-epidioxy-ergosta-6,22(E)-diene-3β-ol(8),kaempferol 3-O-β-D-galactopyranoside(9),glaucogenind C(10),glaucoge-nin A 3-O-β-D-cymaropyranoside(11),dibutyl phthalate(12),cynatratoside A(13),hirundigoside C(14),sublanceoside B2(15),cynanoside A(16),dipentyl phthalate(17),5-hydroxymethyl-2-furancarboxaldehyde(18),bis-(2-ethyl)hexylphthalate(19),p-hydroxybenzoic acid(20),syringic acid(21),β-hydroxypropiovanillone(22),3-hydroxy-l-(4-hydroxy-3,5-dimethoxyphenyl)-1-propanone(23),(+)-syringare sinol(24),(-)-syringare sinol(25),(+)-medioresinol(26).IC50 value of compound 12 was 37.27 μg/mL.CONCLUSION Compounds 1-26 are isolated from this plant for the first time.Compound 12 has inhibitory activity against Phomopsis sp.

Objective:To explore the value of contrast-enhaoced echocardiography for measuring pulmonary transit time（PTT）in assessing heart failure after percutaneous coronary intervention（PCI）in acute ST-segment elevation myocardial infarction（STEMI）patients.Methods:From September 2023 to September 2024，120 patients with STEMI undergoing PCI at Hunan Provincial People's Hospital were prospectively selected and divided into a heart failure group（ n=42）and a non-heart failure group（ n=78）according to the guidelines. The differences in general clinical data，laboratory parameters，and echocardiographic parameters between the two groups were compared. The diagnostic efficacies of PTT，normalized PTT（nPTT），and N-terminal pro-B-type natriuretic peptide（NT-proBNP）were analyzed. Consistency between them and New York Heart Association（NYHA）heart function classification was tested. Results:Compared to the non-heart failure group，the NT-proBNP，PTT，and nPTT values in the heart failure group were significantly increased（all P<0.05）. The area under the curve（AUC）of nPTT was 0.944，better than that of PTT and NT-proBNP（AUC=0.871，0.887）. After K-means clustering reclassified patients into four levels based on nPTT values，nPTT classification showed moderate consistency with NYHA classification（Kappa=0.580， P<0.001），and nPTT differed significantly across NYHA classifications（ P<0.05）. Conclusions:PTT，as an echocardiographic index for assessing cardiac function，has similar diagnostic efficacy to NT-proBNP，the nPTT is even better. It shows moderate consistency with the NYHA classification and holds potential for differentiating overlapping NYHA grades. Importantly，it offers a fresh objective way to evaluate cardiac dysfunction after PCI in STEMI patients.

Glycoengineering was carried out in the mammalian cell line CHO for the production of pro-tein-based drugs.Firstly,the genome sequence of the Rosa26 locus of CHO cells was determined,the gRNA sequences were designed,and the landing pad was integrated into the Rosa26 locus of CHO cells by CRISPR/Cas9 technology.Three targeting vectors co-expressed by glycosyltransferases,which are β-1,4 galactosyltransferase(B4GALT1),α-2,6-sialyltransferase 1(ST6GAL1)and N-acetaminoglycosyl-transferase Ⅲ(GnT Ⅲ),were constructed by overlapping PCR and seamless ligation technology,and the three glycosyltransferase genes were integrated into the CHO Rosa26 locus by Cre enzyme-mediated cassette exchange technology.PCR confirmed that three glycosyltransferases had been successfully site-directed integrated into the Rosa26 site.The mRNA expression levels of the three glycosyltransferases were more than 50 000-fold by qRT-PCR,and the protein expression levels of the three glycosyltrans-ferases were more than 4-fold via western blotting(P＜0.001).A CHO-engineered cell line with three glycosyltransferases integrated into Rosa26 site was successfully constructed.

Objective To observe the value of spectral CT material separation technology for diagnosing traumatic bone marrow edema in limbs.Methods Totally 51 patients with limb traumatic bone marrow edema were retrospectively enrolled and divided into young group(n=26,18-43 years)and middle-aged group(n=25,46-74 years).Taken MRI as reference standard,the efficacy of spectral CT Water-hydroxyapatite(HAP)image for diagnosing bone marrow edema in trauma area was analyzed,and the Water-HAP density values were compared between groups.Results No significant difference of diagnosing bone marrow edema was found between spectral CT and MRI(x2=0.201,P=0.654),and the consistency was high(Kappa=0.774).Water-HAP density value in bone marrow edema area was higher than that in non bone marrow edema area(t=24.634,P＜0.05),and no significant difference of Water-HAP density values in bone marrow edema area nor non bone marrow edema area was found between young group and middle-aged group(both P＞0.05).Conclusion Spectral CT material separation technology was helpful for diagnosing traumatic bone marrow edema in limbs.

T7 RNA polymerase (T7 RNAP) is one of the simplest known RNA polymerases. Its unique structural features make it a critical model for studying the mechanisms of RNA synthesis. This review systematically examines the static crystal structure of T7 RNAP, beginning with an in-depth examination of its characteristic “thumb”, “palm”, and “finger” domains, which form the classic “right-hand-like” architecture. By detailing these structural elements, this review establishes a foundation for understanding the overall organization of T7 RNAP. This review systematically maps the functional roles of secondary structural elements and their subdomains in transcriptional catalysis, progressively elucidating the fundamental relationships between structure and function. Further, the intrinsic flexibility of T7 RNAP and its applications in research are also discussed. Additionally, the review presents the structural diagrams of the enzyme at different stages of the transcription process, and through these diagrams, it provides a detailed description of the complete transcription process of T7 RNAP. By integrating structural dynamics and kinetics analyses, the review constructs a comprehensive framework that bridges static structure to dynamic processes. Despite its advantages, T7 RNAP has a notable limitation: it generates double-stranded RNA (dsRNA) as a byproduct. The presence of dsRNA not only compromises the purity of mRNA products but also elicits nonspecific immune responses, which pose significant challenges for biotechnological and therapeutic applications. The review provides a detailed exploration of the mechanisms underlying dsRNA formation during T7 RNAP catalysis, reviews current strategies to mitigate this issue, and highlights recent progress in the field. A key focus is the semi-rational design of T7 RNAP mutants engineered to minimize dsRNA generation and enhance catalytic performance. Beyond its role in transcription, T7 RNAP exhibits rapid development and extensive application in fields, including gene editing, biosensing, and mRNA vaccines. This review systematically examines the structure-function relationships of T7 RNAP, elucidates the mechanisms of dsRNA formation, and discusses engineering strategies to optimize its performance. It further explores the engineering optimization and functional expansion of T7 RNAP. Furthermore, this review also addresses the pressing issues that currently need resolution, discusses the major challenges in the practical application of T7 RNAP, and provides an outlook on potential future research directions. In summary, this review provides a comprehensive analysis of T7 RNAP, ranging from its structural architecture to cutting-edge applications. We systematically examine: (1) the characteristic right-hand domains (thumb, palm, fingers) that define its minimalistic structure; (2) the structure-function relationships underlying transcriptional catalysis; and (3) the dynamic transitions during the complete transcription cycle. While highlighting T7 RNAP’s versatility in gene editing, biosensing, and mRNA vaccine production, we critically address its major limitation—dsRNA byproduct formation—and evaluate engineering solutions including semi-rationally designed mutants. By synthesizing current knowledge and identifying key challenges, this work aims to provide novel insights for the development and application of T7 RNAP and to foster further thought and progress in related fields.

Background: Oxidative stress causes fatal damage to follicular keratinocytes (FKCs) and is a common pathophysiology of many hair disorders. Objective: This study investigated the protective effects of Red ginseng extract (RGE) and its main ginsenosides against oxidative hair damage using an in vitro organ model of human hair follicles. Methods: We examined whether RGE and its constituent ginsenosides could prevent oxidative damage induced by H 2 O 2 in FKCs by suppressing apoptosis and promoting hair growth. Results: RGE and its main ginsenoside, G-Rb1, significantly inhibited reactive oxygen species production and apoptosis in FKCs. Furthermore, they effectively alleviated the inhibition of hair growth induced by oxidative damage and inhibited the transition of hair from the anagen to the telogen stage. The hair cycle and apoptosis were associated with the modulation of p53 and Bax/Bcl2 signaling. Conclusion RGE and G-Rb1 can effectively mitigate the oxidative damage caused by FKCs, thereby affecting hair growth and hair cycles.

This study explores the effect and mechanism of Banxia Xiexin Decoction(BXD) in inhibiting colon cancer progression by reshaping tryptophan metabolism. Balb/c mice were assigned into control, model, low-dose BXD(BXD-L), and high-dose BXD(BXD-H) groups. Except the control group, the other groups were subcutaneously injected with CT26-Luc cells for the modeling of colon cancer, which was followed by the intervention with BXD. Small animal live imaging was employed to monitor tumor growth, and the tumor volume and weight were measured. Hematoxylin-eosin(HE) staining was used to observe the pathological changes in mouse tumors. Immunohistochemistry was used to detect Ki67 expression in tumors. Immunofluorescence and flow cytometry were used to detect the infiltration and number changes of CD3~+/CD8~+ T cells in the tumor tissue. Enzyme-linked immunosorbent assay(ELISA) was employed to measure the levels of interferon-gamma(IFN-γ) and interleukin-2(IL-2) in tumors. Targeted metabolomics was employed to measure the level of tryptophan(Trp) in the serum, and the Trp content in the tumor tissue was measured. Western blot and RT-qPCR were employed to determine the protein and mRNA levels, respectively, of indoleamine 2,3-dioxygenase 1(IDO1), MYC proto-oncogene, and solute carrier family 7 member 5(SLC7A5) in the tumor tissue. Additionally, a co-culture model with CT26 cells and CD8~+ T cells was established in vitro and treated with the BXD-containing serum. The cell counting kit-8(CCK-8) assay was used to examine the viability of CT26 cells. The content of Trp in CT26 cells and CD8~+ T cells, as well as the secretion of IFN-γ and IL-2 by CD8~+ T cells, was measured. RT-qPCR was used to determine the mRNA levels of MYC and SLC7A5 in CT26 cells. The results showed that BXD significantly inhibited the tumor growth, reduced the tumor weight, and decreased the tumor volume in the model mice. In addition, the model mice showed sparse arrangement of tumor cells, varying degrees of patchy necrosis, and downregulated expression of Ki67 in the tumor tissue. BXD elevated the levels of IFN-γ and IL-2 in the tumor tissue, while upregulating the ratio of CD3~+/CD8~+ T cells and lowering the levels of Trp, IDO1, MYC, and SLC7A5. The co-culture experiment showed that BXD-containing serum reduced Trp uptake by CT26 cells, increased Trp content in CD8~+T cells, enhanced IL-2 and IFN-γ secretion of CD8~+T cells, and down-regulated the mRNA levels of MYC and SLC7A5 in CT26 cells. In summary, BXD can inhibit the MYC/SLC7A5 pathway to reshape Trp metabolism and adjust Trp uptake by CD8~+ T cells to enhance the cytotoxicity, thereby inhibiting the development of colon cancer.
Animals ; Tryptophan/metabolism* ; Colonic Neoplasms/pathology* ; Mice ; Drugs, Chinese Herbal/administration & dosage* ; Mice, Inbred BALB C ; Humans ; Cell Line, Tumor ; Indoleamine-Pyrrole 2,3,-Dioxygenase/metabolism* ; Female ; Disease Progression ; Cell Proliferation/drug effects* ; Proto-Oncogene Mas ; Male