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*

Integrated medical courses are one of the key models for the development and transformation of modern medical education. Modular-based integrated courses set higher standards for knowledge, skills and quality objectives. This article primarily discusses the specific practices of teaching reform in the integrated medical course of Frontiers of Infection and Immunity for eight-year program at Air Force Medical University. It covers the selection and integration of teaching content, innovative application of various teaching methods, diversified teaching evaluation and feedback, and the teaching team building. The course not only deepens students' knowledge and promotes their creative abilities but also enhances their comprehensive literacy and international perspective, thus effectively preparing high-quality medical talents for future challenges in the medical field.
Humans ; Education, Medical/methods* ; Teaching ; Curriculum ; Immunity ; Infections/immunology*

Humans ; Melanocytes ; Melanosis ; Fibroblasts ; Skin

In mammals, the piezoelectric protein, Prestin, endows the outer hair cells (OHCs) with electromotility (eM), which confers the capacity to change cellular length in response to alterations in membrane potential. Together with basilar membrane resonance and possible stereociliary motility, Prestin-based OHC eM lays the foundation for enhancing cochlear sensitivity and frequency selectivity. However, it remains debatable whether Prestin contributes to ultrahigh-frequency hearing due to the intrinsic nature of the cell's low-pass features. The low-pass property of mouse OHC eM is based on the finding that eM magnitude dissipates within the frequency bandwidth of human speech. In this study, we examined the role of Prestin in sensing broad-range frequencies (4-80 kHz) in mice that use ultrasonic hearing and vocalization (to >100 kHz) for social communication. The audiometric measurements in mice showed that ablation of Prestin did not abolish hearing at frequencies >40 kHz. Acoustic associative behavior tests confirmed that Prestin-knockout mice can learn ultrahigh-frequency sound-coupled tasks, similar to control mice. Ex vivo cochlear Ca²⁺ imaging experiments demonstrated that without Prestin, the OHCs still exhibit ultrahigh-frequency transduction, which in contrast, can be abolished by a universal cation channel blocker, Gadolinium. In vivo salicylate treatment disrupts hearing at frequencies <40 kHz but not ultrahigh-frequency hearing. By pharmacogenetic manipulation, we showed that specific ablation of the OHCs largely abolished hearing at frequencies >40 kHz. These findings demonstrate that cochlear OHCs are the target cells that support ultrahigh-frequency transduction, which does not require Prestin.
Animals ; Cochlea/metabolism* ; Hair Cells, Auditory, Outer/metabolism* ; Hearing ; Humans ; Mammals/metabolism* ; Mice ; Mice, Knockout ; Molecular Motor Proteins/metabolism*

It has long been noted that dermabrasion, plum-blossom needling or micro-needling, and even ablative fractional CO 2 laser can effectively induce repigmentation of vitiligo lesions resistant to conventional ultraviolet B phototherapy. In addition to trauma-induced increase in the transdermal absorption of drugs, these treatments also initiate wound repair and activate melanocytes in hair follicles or epidermis. Basal layer keratinocytes, vascular endothelial cells and fibroblasts in the wound margins can secrete chemokine CXCL12 to recruit melanocytes or melanocyte stem cells expressing chemokine receptors CXCR4/CXCR7 in the hair follicle bulge or around the skin lesions to move towards the vitiliginous area. This review summarizes progress in repigmentation of vitiligo lesions induced by therapeutic skin trauma.

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 explore the predictive value of various ultrasonic signs for papillary thyroid microcarcinoma (PTMC) .Methods:The ultrasonic data of of 603 micronodular goiter (MNG) in 396 cases and 640 PTMC in 539 cases, which were confirmed by pathology from Jan. 2013 to Dec. 2016, were retrospectively analyzed. According to the different inspection time, all nodules were divided into model group (2013-2014 years) and test group (2015-2016 years) . The tumor morphology, internal echo, microcalcification, and aspect ratio (A/T) were observed. Chi-square test and multivariate Logistic regression analysis were used to analyze the distribution differences of the four ultrasound features in PTMC and MNG, and their diagnostic value was evaluated.Results:There were statistical difference between model group and test group in ultrasonic signs including tumors shape, internal echo, microcalcification and aspect ratio according single factor analysis (chi square value was 283.540 and 298.119, 63.130 and 87.400, 26.342 and 50.152, 169.918 and 181.405; P<0.05) ;Multivariable Logistic regression analysis showed that irregular shape, hypoecho, A/T>1 and microcalcification were more common in PTMC ( P< 0.05) . OR values were 18.410 and 19.231, 2.560 and 6.380, 9.379 and 6.724, 3.102 and 8.830, and AUC prediction probability values were 0.916 and 0.911 respectively. Conclusions:Irregular shape, internal hypoechoic, microcalcification and A/T>1 are stable important ultrasonographic signs in predicting PTMC. Comprehensive analysis of various ultrasonic signs can improve the diagnostic efficiency.

Objective To explore the value of ultrasound gray scale ratio (UGSR) in the diagnosis and differential diagnosis of papillary thyroid carcinoma(PTC) with different sizes.Methods A retrospective study was made in 702 patients with 1107 nodules which were confirmed by surgery in the Department of Oncology or fineneedle aspiration of HangZhou First people's Hospital,Zhejiang University of medical school from Jan.2016 to Oct.2017.All the thyroid nodules were divided into three groups:D≤ 1 cm group,1＜D≤2 cm group and ＞2 cm group according to their sizes.The UGSR of the PTC and NG were obtained through the RAD info system.Their differences were analyzed and ROC was established to confirm the optimal threshold in the differential diagnosis between PTC and NG among the groups.Results There were 483 PTC and 624 NG in this study.The UGSR of D≤ 1 cm group,1＜D≤2 cm group and ＞2 cm group of PTC and NG were (0.48±0.12) vs (0.76±0.22)(t=33.21,P=0.00);(0.52±0.17) vs(0.80±0.21)(t=1.30,P=0.00) and (0.63±0.20) vs(0.89±0.24)(t=3.58,P=0.00) respectively.The area under the ROC of UGSR in the differentiation of PTC and NG in the three groups were 0.873,0.840 and 0.811 respectively.The Youden indexes were greatest (0.631,0.536 and 0.535 respectively),when the cut-offs of the UGSR were 0.682,0.652 and 0.831 respectively.The sensitivity and specificity to diagnose PTC were 94.8％ and 68.0％,75.0％ and 78.6％,80.3％ and 73.2％ respectively in the three groups.Conclusions The best UGSR value of PTC was variant in thyroid nodule with different size.Recognition of these differences accurately could improve the pre-operative diagnostic accuracy of PTC.Also the method is simple to operate and easy to apply.

To construct a eukaryotic expression plasmid containing the luciferase reporter gene (Fluc) to quickly detect apoptosis. Four amino acids, Asp-Glu-Val-Asp (DEVD), the recognize motif of Caspase-3, were introduced into the middle of the Fluc-C and N fragment. Meanwhile, four amino acids, Asp-Glu-Val-Gly (DEVG), were selected as a negative control. Subsequently, the recombinant gene was cloned into the N and C terminal end of the split intein, and named as pFluc-DEVD and pFluc-DEVG. Then the plasmids were transfected into cells and renilla luciferase was co-transfected in each sample as an internal control for transfection efficiency. Then the apoptosis level was detected by the double luciferase reporter gene and the Western blotting analysis. The results showed that when apoptosis occurred, the content of firefly luciferase expressed in the pFluc-DEVD plasmid transfected group was about 3 times higher than pFluc-DEVG plasmid transfected group. Furthermore, Western blotting detection indicated that the Fluc level was significantly increased in pFluc-DEVD transfected group when pre-treated by apoptosis stimulants. The activation degree of Caspase-3 was closely related to the expression of Fluc, and had a significant statistical difference. These results confirmed that firefly luciferase protein expressed by pFluc-DEVD plasmid can be cleaved by the intracellular Caspase-3 enzyme, and this plasmid can accurately reflect the cell apoptosis level, which provides a useful method for quantitative detection of apoptosis.
Apoptosis ; Genes, Reporter ; Luciferases, Firefly ; Transfection

Objective To evaluate the clinical value of contrast-enhanced ultrasonography (CEUS) in the diagnosis of central lung cancer with obstructive atelectasis. Methods During the period from July 2015 to October 2017, 36 central lung cancer patients with atelectasis were admitted to the First People's Hospital of Hangzhou. All the patients were diagnosed by clinical pathology, and the lesions can be demonstrated by ultrasound. CEUS was performed on all the patients. After the examination, the time from which central lung cancer began to increase, the time at which the lungs began to inflate, and the peak and disappearance time of both were analyzed, and the enhancement pattern of the lesions were observed. Results CEUS clearly distinguished central lung cancer and atelectasis in all the 36 (100%) patients. CEUS showed central lung cancer as ″slow-in and fast-out″ mode in 32 of 36 patients, and as ″fast-out and fast-in″mode in the remaining four cases. Among all patients, 18 had uniform low enhancement, 12 had non-uniform low enhancement, 4 had uniform high enhancement, and 2 had non-uniform high enhancement. The onset enhancement time was 4-10 seconds in 32 patients, and 10-18 seconds in 4 cases. The onset enhancement time of the tumor tissue was 10-15 seconds. Conclusion CEUS can distinguish tumor tissue from atelectasis and is helpful in discovering tumor tissue hidden in atelectasis.