BACKGROUND: Increasing evidence indicates that oxidative stress and interferon γ (IFNγ)-driven cellular immune responses are responsible for the pathogenesis of vitiligo. However, the connection between oxidative stress and the local production of IFNγ in early vitiligo remains unexplored. The aim of this study was to identify the mechanism underlying the production of IFNγ by mast cells and its impact on vitiligo pathogenesis. METHODS: Skin specimens from the central, marginal, and perilesional skin areas of active vitiligo lesions were collected to characterize changes of mast cells, CD8 + T cells, and IFNγ-producing cells. Cell supernatants from hydrogen peroxide (H 2 O 2 )-treated keratinocytes (KCs) were harvested to measure levels of soluble stem cell factor (sSCF) and matrix metalloproteinase (MMP)-9. A murine vitiligo model was established using Mas-related G protein-coupled receptor-B2 (MrgB2, mouse ortholog of human MrgX2) conditional knockout (MrgB2 -/- ) mice to investigate IFNγ production and inflammatory cell infiltrations in tail skin following the challenge with tyrosinase-related protein (Tyrp)-2 180 peptide. Potential interactions between the Tyrp-2 180 peptide and MrgX2 were predicted using molecular docking. The siRNAs targeting MrgX2 and the calcineurin inhibitor FK506 were also used to examine the signaling pathways involved in mast cell activation. RESULTS: IFNγ-producing mast cells were closely aligned with the recruitment of CD8 + T cells in the early phase of vitiligo skin. sSCF released by KCs through stress-enhanced MMP9-dependent proteolytic cleavage recruited mast cells into sites of inflamed skin (Perilesion vs . lesion, 13.00 ± 4.00/high-power fields [HPF] vs . 26.60 ± 5.72/HPF, P <0.05). Moreover, IFNγ-producing mast cells were also observed in mouse tail skin following challenge with Tyrp-2 180 (0 h vs . 48 h post-recall, 0/HPF vs . 3.80 ± 1.92/HPF, P <0.05). The IFNγ + mast cell and CD8 + T cell counts were lower in the skin of MrgB2 -/- mice than in those of wild-type mice (WT vs . KO 48 h post-recall, 4.20 ± 0.84/HPF vs . 0.80 ± 0.84/HPF, P <0.05). CONCLUSION Mast cells activated by MrgX2 serve as a local IFNγ producer that bridges between innate and adaptive immune responses against MCs in early vitiligo. Targeting MrgX2-mediated mast cell activation may represent a new strategy for treating vitiligo.
Vitiligo/metabolism* ; Mast Cells/immunology* ; Animals ; Interferon-gamma/metabolism* ; Mice ; Humans ; Melanocytes/metabolism* ; Receptors, G-Protein-Coupled/genetics* ; Mice, Knockout ; Mice, Inbred C57BL ; Male ; Female ; Matrix Metalloproteinase 9/metabolism* ; Stem Cell Factor/metabolism*

OBJECTIVE: To investigate the impact of bone mass and volume of low-density zones beneath the tibial plateau on the maximum von Mises stresses experienced by the cartilage and meniscus in the knee joint. METHODS: The study included one healthy adult volunteer, from whom CT scans were obtained, and one patient diagnosed with knee osteoarthrisis (KOA), for whom X-ray films were acquired. A static model of the knee joint featuring a low-density zone was established based on a normal knee model. In the finite element analysis, axial loads of 1 000 N and 1 800 N were applied to the weight-bearing region of the upper surface of the femoral head for model validation and subsequent finite element studies, respectively. The maximum von Mises stresses in the femoral cartilage, as well as the medial and lateral tibial cartilage and menisci, were observed, and the stress percentage of the medial and lateral components were concurrently analyzed. Additionally, HE staining, as well as alkaline magenta staining, were performed on the pathological specimens of patients with KOA in various low-density regions. RESULTS: The results of model validation indicated that the model was consistent with normal anatomical structures and correlated with previous calculations documented in the literature. Static analysis revealed that the maximum von Mises stress in the medial component of the normal knee was the lowest and increased with the advancement of the hypointensity zone. In contrast, the lateral component exhibited an opposing trend, with the maximum von Mises stress in the lateral component being the highest and decreasing as the hypointensity zone progressed. Additionally, the medial component experienced an increasing proportion of stress within the overall knee joint. HE staining demonstrated that the chondrocyte layer progressively deteriorated and may even disappear as the hypointensity zone expanded. Furthermore, alkaline magenta staining indicated that the severity of microfractures in the trabecular bone increased concurrently with the expansion of the hypointensity zone. CONCLUSION The presence of subtalar plateau low-density zone may aggravate joint degeneration. In clinical practice, it is necessary to pay attention to the changes in the subtalar plateau low-density zone and actively take effective measures to strengthen the bone status of the subtalar plateau low-density zone and restore the complete biomechanical function of the knee joint, in order to slow down or reverse the progression of osteoarthritis.
Humans ; Finite Element Analysis ; Knee Joint/physiology* ; Tibia/anatomy & histology* ; Cartilage, Articular/physiology* ; Menisci, Tibial/physiopathology* ; Tomography, X-Ray Computed ; Osteoarthritis, Knee/diagnostic imaging* ; Weight-Bearing ; Bone Density ; Adult ; Stress, Mechanical ; Male ; Middle Aged ; Biomechanical Phenomena ; Female

Objective:To investigate effects of rutin on ultraviolet irradiation (UVR) -induced human dermal fibroblast (FB) senescence and melanogenesis in mouse ear skin.Methods:The third- to fifth-passage FBs were divided into 4 groups: a blank control group, a UVR group, a rutin group, and a combined treatment group. In the UVR group, FBs were irradiated using an ultraviolet irradiator at a single dose of 0.6 J/cm 2 UVA combined with 0.03 J/cm 2 UVB once daily for 5 consecutive days; FBs in the rutin group were cultured in Dulbecco's modified Eagle medium containing 50 μmol/L rutin for 5 days; the combined treatment group received both UVR and the treatment with 50 μmol/L rutin for 5 days; the blank control group underwent no treatment. β-Galactosidase staining was performed to assess the senescence of FBs, real-time quantitative PCR (qPCR) to measure the telomere length in FBs, and Western blot analysis to detect the expression levels of stem cell factor (SCF) in FB cell lysates and culture supernatants. FB culture supernatants were collected from each group, and mixed with M254 medium at a ratio of 3∶1 to prepare conditioned medium, which was then used to treat PIG1 melanocytes for 24 hours. Western blot analysis was conducted to determine the tyrosinase (TYR) expression in PIG1 melanocytes in each group, while the 5-ethynyl-2′-deoxyuridine (EdU) incorporation assay was applied to assess the proliferative activity of PIG1 cells in each group. Ten Dct-LacZ transgenic mice were divided into a control group and a UVR group. For each mouse, 5% rutin-containing cream was topically applied to the right ear after UVR, while the left ear treated with the cream base alone served as a control. Skin biopsies were performed after 4 weeks, followed by X-gal staining and Avidin/fluorescein isothiocyanate (FITC) staining to count the numbers of melanocytes and mast cells in mouse ear skin. Results:In the UVR group, the number of senescent FBs (25.67 ± 2.89), relative protein expression levels of SCF (1.95 ± 0.22), and relative levels of SCF in the cell culture supernatant (1.52 ± 0.34) were all significantly higher than those in the blank control group (5.67 ± 1.56, 0.95 ± 0.11, 1.01 ± 0.31, respectively), while these indicators were significantly lower in the combined treatment group (12.00 ± 1.63, 1.32 ± 0.19, 1.15 ± 0.32, respectively) than in the UVR group (all P < 0.05). The relative telomere length in FBs was significantly shorter in the UVR group (0.49 ± 0.12) than in the blank control group (0.94 ± 0.11; LSD- t = 3.15, P = 0.021), but significantly longer in the combined treatment group (0.81 ± 0.13) than in the UVR group (LSD- t = 4.30, P = 0.034). After the treatment with FB conditioned medium, the relative expression level of TYR in PIG1 melanocytes and the number of EdU-positive cells were significantly higher in the UVR group (2.54 ± 0.21, 33.54 ± 3.21, respectively) than in the blank control group (0.97 ± 0.19, 21.45 ± 2.51, respectively; both P < 0.001), but significantly lower in the combined treatment group (1.63 ± 0.12, 18.54 ± 3.87, respectively) than in the UVR group (both P < 0.001). X-gal staining and Avidin/FITC staining showed that the numbers of melanocytes and mast cells in the mouse left ear skin in the UVR group (5.00 ± 1.22, 98.60 ± 8.47, respectively) were significantly higher than those in the mouse left ear skin in the control group (1.80 ± 0.45, 53.80 ± 5.76, respectively) and those in the mouse right ear skin treated with the rutin-containing cream in the UVR group (2.80 ± 0.45, 69.60 ± 8.89, respectively) (all P < 0.05) . Conclusion:Rutin may inhibit UVR-induced skin melanogenesis by suppressing the senescence of dermal FBs and paracrine secretion of SCF.

Objective:To investigate effects of rutin on ultraviolet irradiation (UVR) -induced human dermal fibroblast (FB) senescence and melanogenesis in mouse ear skin.Methods:The third- to fifth-passage FBs were divided into 4 groups: a blank control group, a UVR group, a rutin group, and a combined treatment group. In the UVR group, FBs were irradiated using an ultraviolet irradiator at a single dose of 0.6 J/cm 2 UVA combined with 0.03 J/cm 2 UVB once daily for 5 consecutive days; FBs in the rutin group were cultured in Dulbecco's modified Eagle medium containing 50 μmol/L rutin for 5 days; the combined treatment group received both UVR and the treatment with 50 μmol/L rutin for 5 days; the blank control group underwent no treatment. β-Galactosidase staining was performed to assess the senescence of FBs, real-time quantitative PCR (qPCR) to measure the telomere length in FBs, and Western blot analysis to detect the expression levels of stem cell factor (SCF) in FB cell lysates and culture supernatants. FB culture supernatants were collected from each group, and mixed with M254 medium at a ratio of 3∶1 to prepare conditioned medium, which was then used to treat PIG1 melanocytes for 24 hours. Western blot analysis was conducted to determine the tyrosinase (TYR) expression in PIG1 melanocytes in each group, while the 5-ethynyl-2′-deoxyuridine (EdU) incorporation assay was applied to assess the proliferative activity of PIG1 cells in each group. Ten Dct-LacZ transgenic mice were divided into a control group and a UVR group. For each mouse, 5% rutin-containing cream was topically applied to the right ear after UVR, while the left ear treated with the cream base alone served as a control. Skin biopsies were performed after 4 weeks, followed by X-gal staining and Avidin/fluorescein isothiocyanate (FITC) staining to count the numbers of melanocytes and mast cells in mouse ear skin. Results:In the UVR group, the number of senescent FBs (25.67 ± 2.89), relative protein expression levels of SCF (1.95 ± 0.22), and relative levels of SCF in the cell culture supernatant (1.52 ± 0.34) were all significantly higher than those in the blank control group (5.67 ± 1.56, 0.95 ± 0.11, 1.01 ± 0.31, respectively), while these indicators were significantly lower in the combined treatment group (12.00 ± 1.63, 1.32 ± 0.19, 1.15 ± 0.32, respectively) than in the UVR group (all P < 0.05). The relative telomere length in FBs was significantly shorter in the UVR group (0.49 ± 0.12) than in the blank control group (0.94 ± 0.11; LSD- t = 3.15, P = 0.021), but significantly longer in the combined treatment group (0.81 ± 0.13) than in the UVR group (LSD- t = 4.30, P = 0.034). After the treatment with FB conditioned medium, the relative expression level of TYR in PIG1 melanocytes and the number of EdU-positive cells were significantly higher in the UVR group (2.54 ± 0.21, 33.54 ± 3.21, respectively) than in the blank control group (0.97 ± 0.19, 21.45 ± 2.51, respectively; both P < 0.001), but significantly lower in the combined treatment group (1.63 ± 0.12, 18.54 ± 3.87, respectively) than in the UVR group (both P < 0.001). X-gal staining and Avidin/FITC staining showed that the numbers of melanocytes and mast cells in the mouse left ear skin in the UVR group (5.00 ± 1.22, 98.60 ± 8.47, respectively) were significantly higher than those in the mouse left ear skin in the control group (1.80 ± 0.45, 53.80 ± 5.76, respectively) and those in the mouse right ear skin treated with the rutin-containing cream in the UVR group (2.80 ± 0.45, 69.60 ± 8.89, respectively) (all P < 0.05) . Conclusion:Rutin may inhibit UVR-induced skin melanogenesis by suppressing the senescence of dermal FBs and paracrine secretion of SCF.

As an emerging drug delivery technology,microneedles can puncture the skin's stratum corneum to create micron-sized conduits,painlessly,minimally invasive,and efficiently deliver drugs into viable epidermis or dermis for local or systemic therapeutic effects.This paper reviews the current clinical trials of microneedles used in the treatment of various diseases,elaborates on the characteristics of various types of microneedles,and summarizes the latest research progress of microneedles used to treat skin tumors,including chemotherapy,photothermal and photodynamic therapy,immunotherapy,gene therapy,and combination therapy.This review provides ideas and directions for further research on microneedles in treating skin tumors.

Objective:The present study was designed to strengthen the education of research integrity, and to improve the awareness of academic misconduct and academic literacy of medical post-graduate students.Methods:A questionnaire survey was conducted with master post-graduate students of a university affiliated hospital, and statistical analysis on the education of research integrity and the perception of academic misconduct among the survey respondents was performed.Results:Academic master post-graduate students′ cognitions of the misconduct in scientific research process and overall academic misconduct were better than that of professional master post-graduate students, and there were significant differences ( P<0.05). The more times of participation in research integrity training, the better cognition of misconduct of scientific research process, research results publication process, and overall academic misconduct, with significant differences ( P<0.05). Conclusions:The education on scientific research integrity of medical post-graduates should be carried out systematically, while the content should be improved and the form should be enriched for scientific research integrity education, so that the medical post-graduates can have a deeper understanding of the code of academic practices, and an education model of scientific research integrity for medical post-graduate which is suitable for China′s national conditions can be gradually developed.

Despite being a common therapy for hepatocellular carcinoma (HCC), insufficient thermal ablation can leave behind tumor residues that can cause recurrence. This is believed to augment M2 inflammatory macrophages that usually play a pro-tumorigenic role. To address this problem, we designed d-mannose-chelated iron oxide nanoparticles (man-IONPs) to polarize M2-like macrophages into the antitumor M1 phenotype. In vitro and in vivo experiments demonstrated that man-IONPs specifically targeted M2-like macrophages and accumulated in peri-ablation zones after macrophage infiltration was augmented under insufficient microwave ablation (MWA). The nanoparticles simultaneously induced polarization of pro-tumorigenic M2 macrophages into antitumor M1 phenotypes, enabling the transformation of the immunosuppressive microenvironment into an immunoactivating one. Post-MWA macrophage polarization exerted robust inhibitory effects on HCC progression in a well-established orthotopic liver cancer mouse model. Thus, combining thermal ablation with man-IONPs can salvage residual tumors after insufficient MWA. These results have strong potential for clinical translation.

Objective:To explore the value of multi-parametric MRI for thyroid gland in differentiating benign and malignant thyroid nodules.Methods:From December 2018 to May 2020, 78 patients with 91 post-surgically pathologically confirmed thyroid nodules were enrolled in Cancer Hospital & Shenzhen Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. For each patient, the following MRI findings were obtained including the nodules′ location, size, shape, margin, signal intensity, cystic change, degree and pattern of contrast enhancement, involvement of surrounding structure, and ADC values. The time-intensity curve (TIC) were plotted and subtyped based on dynamic contrast enhancement MRI. The MRI findings between the benign and malignant thyroid nodules were compared using Mann-Whitney U test, χ 2 test or Fisher exact test. Multiple logistic regression analysis was used to select independent predictive variables and build a combined model, and the ROC curve was used to evaluate the diagnostic performance of each MRI finding and the combined model. Results:Between the benign and malignant thyroid nodules, the significant differences were found in size, shape, margin, presence of cystic changes, T 1WI signal intensity, ADC value, enhancement homogeneity, TIC subtypes and presence of thyroid capsule involvement ( P<0.05). Multivariate logistic analysis showed that ill-defined margin (OR=77.61), no presence of cystic changes (OR=36.11) and difference between TIC subtypes (OR=83.41) were independent predictive variables, and the area under the ROC curve (AUC) was 0.879, 0.788, and 0.751, respectively. The AUC, sensitivity and specificity of the combined model were 0.977, 0.986, and 0.904, respectively. Conclusions:Thyroid multi-parametric MRI derived findings can be used for the differential diagnosis of benign and malignant nodules. Combined with the independent risk factors with ill-defined margin, no presence of cystic changes, TIC of type plateau or washout, the diagnostic model has a higher diagnostic efficiency.

Objective:To investigate the expression and distribution of human dermal papillary fibroblasts (Fp) , reticular fibroblasts (Fr) , and myofibroblasts (MFB) in keloid tissues.Methods:Keloid tissues were collected from 15 outpatients (including 8 males and 7 females) aged 20-50 years, who were diagnosed in the Department of Dermatology, Renmin Hospital of Wuhan University from May to December 2019. Normal skin tissues were taken from 15 age-matched women who underwent mammoplasty, and served as controls. The distribution of fibroblast activation protein (FAP) , CD90 and alpha-smooth muscle actin (α-SMA) was observed in the keloid tissues and normal skin tissues by dual immunofluorescence staining. Furthermore, fibroblasts were isolated from 3 normal skin and 3 keloid tissue samples, and subjected to primary culture. Subsequently, the fibroblasts were treated with 10 ng/ml transforming growth factor-β1 (TGF-β1) for 48 hours in vitro, during which, changes in fibroblast phenotypes were observed in the 2 groups. Fluorescence-based quantitative RT-PCR and Western blot analysis were performed to determine the mRNA and protein expression of FAP, CD90 and α-SMA. Measurement data were compared between 2 groups by using t test. Results:Immunofluorescence staining of the normal skin tissues revealed that FAP +/CD90 - fibroblasts were predominantly distributed in the superficial dermis, FAP -/CD90 + fibroblasts in the deep dermis, and CD90 + cells hardly expressed α-SMA; however, a large number of FAP + fibroblasts and CD90 + fibroblasts were observed in the deep keloid tissues, and many CD90 + fibroblasts also expressed α-SMA. Dual immunofluorescence staining showed that normal tissue-derived fibroblasts hardly expressed α-SMA, and keloid-derived fibroblasts expressed α-SMA. The fluorescence intensity of α-SMA + cells significantly increased in the normal tissue-and keloid-derived fibroblasts after 24-hour treatment with TGF-β1 (21.058 ± 0.709, 27.112 ± 0.097, respectively) compared with that in the corresponding untreated fibroblasts (11.312 ± 0.636, 21.306 ± 0.464, t=22.430, 13.370, respectively, both P < 0.05) . RT-PCR and Western blot analysis showed that the mRNA and protein expression of FAP, CD90 and α-SMA significantly increased in the keloid-derived fibroblasts after 48-hour treatment with TGF-β1 (mRNA: 92.610 ± 3.667, 1.366 ± 0.105, 3.240 ± 0.141; protein: 0.652 ± 0.073, 1.046 ± 0.119, 0.946 ± 0.117, respectively) compared with the untreated keloid-derived fibroblasts (all P < 0.05) . Conclusion:CD90 + Fr aberrantly proliferated in the deep dermis of keloid tissues, suggesting that directional intervention in aberrantly proliferating FAP -/CD90 + Fr in the deep dermis may promote the efficacy for keloids.

Objective: To evaluate the pathogenicity of Acinetobacter venetum（Av），which is expected to be used as an environmental remediation agent，using Caenorhabditis elegans（C.elegans）. Methods: The C.elegans were cultured on the media loaded with E.coli OP50 and Av，respectively. The pathogenicity of Av was evaluated by observing the effects of Av on the growth，movement，digestive function，lifespan and reproduction of C.elegans，compared with that of another evaluation system according to NY 1109-2017 General Biosafety Standard for Microbial Fertilizers. Results: By C. elegans system，it was found that the body length，width，head thrash frequency，body bending frequency and average lifespan [（13.5±0.4）d vs.（13.7±0.4）d] of adult nematodes in the Av group were not significantly different from those in the OP50 group（all P>0.05）；while the average time of defecation cycle in the Av group shortened，the total number of progenies in the Av group increased by 18.7%（all P<0.05）. According to NY1109-2017 General Biosafety Standard for Microbial Fertilizers，it was found that the oral LD50 values for both male and female mice were more than 10 g/kgbw，which was practically non-toxic；the pathogenicity test of acute intraperitoneal injection showed that the animals did not have signs of poisoning，deaths or any abnormalities in gross anatomy；Av had no irritation to damaged skin and eyes of rabbits；the hemolysis test was negative；Av was sensitive to seven antibiotics and was medium to one antibiotic. Conclusion Av is not pathogenic. C. elegans can be used in early screening for the pathogenicity of environmental remediation agents.