The construction of a training system for visiting physicians in the department of rare diseases in China is an important measure to improve the overall diagnosis and treatment capacity for rare diseases and address the critical challenge of insufficient knowledge and skills among clinicians in practice. This article systematically describes the visiting physician training system established by the Department of Rare Diseases at Peking Union Medical College Hospital. It summarizes the training objectives and positioning, design logic, and learning modules of the system, aiming to provide a reference for the construction of the specialized talent team for rare diseases in China.

To investigate the clinical efficacy of neoadjuvant imatinib in the treatment of rectal gastrointestinal stromal tumor (GIST).

A 51-year-old male presented with nasal obstruction, followed by progressive hearing loss and blurred vision. Imaging identified space-occupying lesions in the paranasal sinuses, orbits, and paraspinal regions, while laboratory tests confirmed positive anti-proteinase 3 anti-neutrophil cytoplasmic antibody(PR3- ANCA) immunoglobulin G (IgG)and markedly elevated serum IgG4. Despite treatment with corticosteroids, immunosuppressants, and radiotherapy, the patient exhibited steroid dependency with relentless disease progression. Following multidisciplinary consultation, a diagnosis of inflammatory myofibroblastic tumor (IMT) coexisting with ANCA- associated vasculitis (AAV) was favored, though IgG4-related disease remained a critical differential. Ultimately, profound immunosuppression precipitated a severe herpesvirus infection, leading to disseminated intravascular coagulation and multiple organ dysfunction syndrome. This case underscores the rarity and diagnostic complexity of concurrent IMT and AAV, highlights the therapeutic dilemma of balancing primary disease control against fatal opportunistic infections, and emphasizes the critical role of multidisciplinary collaboration in the diagnosis and treatment of complex diseases.

Gorham-Stout disease(GSD) is a rare osteolytic disorder characterized by spontaneous and progressive osteolysis, along with abnormal angiogenesis and lymphangiogenesis, with no new bone formation. We present a case of a 15-year-old female admitted due to " recurrent right leg pain for 5 years, 11 months after undergoing right femoral fracture surgery". Through comprehensive integration of the patient's clinical phenotype, laboratory tests, imaging findings, pathological examinations, and molecular biological test results, GSD was considered highly likely. A multidisciplinary treatment approach was conducted, including a combination of zoledronic acid and sirolimus to inhibit osteolysis, along with rehabilitation training and orthopedic intervention, providing a personalized and comprehensive treatment strategy.

VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome is an adult-onset, X-linked clonal autoinflammatory disease caused by somatic mutations in the UBA1 gene, characterized by systemic inflammation accompanied by hematologic clonal abnormalities. Somatic UBA1 mutations result in impaired ubiquitination, disruption of protein homeostasis, and sustained activation of inflammatory signaling pathways, including nuclear factor-κB and Janus kinase-signal transducer and activator of transcription (JAK-STAT), which together constitute the core pathogenic mechanism. The disease involves multiple systems and tissues including the hematologic system, skin, cartilage and respiratory system, showing remarkable clinical heterogeneity. Diagnosis depends primarily on the combination of characteristic clinical manifestations and molecular confirmation of UBA1 mutations. Current therapeutic strategies lack a unified standard: glucocorticoids can rapidly control inflammation but are associated with high relapse rates, whereas targeted therapies such as JAK inhibitors, interleukin inhibitors, and hypomethylating agents show variable efficacy, and allogeneic hematopoietic stem cell transplantation offers curative potential in patients with concomitant myelodysplastic syndrome. This review systematically summarizes the genetic background, molecular mechanisms, clinical spectrum, diagnostic criteria, and therapeutic advances of VEXAS syndrome.

The therapeutic effect of human umbilical cord mesenchymal stem cells (hUCMSCs) combined with intestinal probiotics on the wound healing of diabetic mice and its potential mechanism were explored. A diabetic wound mouse model was established, and 25 male C57BL/6J mice were randomly divided into five groups: blank control group, model group, hUCMSCs treatment group, probiotics treatment group, and hUCMSCs combined with probiotics treatment group. The wound healing conditions were photographed and recorded on days 0, 3, 6, 9, and 12 after modeling, and the differences in wound healing rates among the groups were analyzed. HE and Masson staining were used to observe the histopathological changes and collagen deposition. CD31 immunofluorescence was used to detect angiogenesis. Collagen I immunohistochemistry was used to evaluate the formation of type I collagen. ELISA was used to detect the expression levels of anti-inflammatory factors (Arg1) and pro-inflammatory factors (IL-6, IL-1β, TNF-α) in wounded skin tissue and serum. The results showed that on day 12 after modeling, compared with the other groups, the combined treatment group had the most significant wound contraction and the fastest healing rate. HE and Masson staining showed that the combined treatment group had the fastest epithelialization and the most collagen deposition. Immunofluorescence and immunohistochemistry showed that the combined treatment group had the highest expression levels of CD31 and Collagen I. ELISA results indicated that the combined treatment group had higher expression levels of Arg1 in wound skin tissue and serum than the other groups, while the expression levels of IL-6, IL-1β, and TNF-α were significantly lower. These results suggest that the combined treatment of hUCMSCs and intestinal probiotics can accelerate wound healing in diabetic mice through mechanisms such as promoting angiogenesis, enhancing collagen deposition, and regulating the inflammatory microenvironment. The therapeutic effect was significantly better than that of single treatment, providing a new potential strategy for the clinical treatment of diabetic foot.

ObjectiveTo investigate the effects of metformin on the immune functions of immature dendritic cells （imDCs） and the underlying mechanisms. MethodsMouse bone marrow-derived imDCs were treated with different concentrations of metformin. The working concentration and treatment time of metformin in this study were determined based on the results of cell apoptosis and cell viability assays. The effects of metformin on the phagocytic capacity of imDCs was evaluated using an antigen endocytosis assay. The expression of cluster of differentiation 205 （CD205）， the polymerization of filamentous actin （F-actin）， and the underlying regulatory mechanisms were investigated through flow cytometry， laser confocal fluorescence microscopy， and Western blot. ResultsThe working concentrations of metformin were 1， 2， 4 mmol/L for 24 h determined by the apoptosis and cell viability assays.Metformin significantly suppressed the phagocytic capacity of imDCs， down-regulated the expression of the mannose receptor CD205 on the cell surface， which was closely associated with phagocytic function； metformin inhibited the RhoA-ROCK1-LIMK1-Cofilin signaling pathway， which inhibited the polymerization of F-actin and disturbed its dynamic remodeling of imDCs. ConclusionMetformin can inhibit the expression of CD205 and disrupt the remodeling of F-actin， thereby suppressing the antigen-capturing capacity of imDCs.

Purpose: Children with tic disorders/Tourette syndrome (TD/TS) frequently present with co-occurring neuropsychiatric conditions, such as obsessive-compulsive disorder and a range of behavioral issues. However, these accompanying problems may be overlooked during diagnosis. This study aimed to investigate the neurocognitive and behavioral characteristics of children with TD/TS who visited a pediatric clinic. Methods: We retrospectively reviewed medical records of children diagnosed with TD/TS at a secondary referral center in Korea. A subset of these data was statistically compared with those from healthy controls. To minimize confounding factors, only children with cognitive development within the normal range were included. Results: Data from 36 children with TD/TS (27 males, nine females; ages 6 to 14 years, mean 9.5±2.1) were analyzed. The mean Full Scale Intelligence Quotient (FSIQ) on the Korean–Wechsler Intelligence Scales for Children (K-WISC) was 98.8±11.7 (n=24). Compared with healthy controls (n=38), the TD/TS group (n=13) scored significantly lower on the Perceptual Reasoning Index, despite no group difference in overall FSIQ (K-WISC-IV). On the Korean Child Behavior Checklist, the TD/TS group showed significantly higher rates of clinical-range scores in multiple domains, including anxiety, somatic complaints, attention problems, and obsessive-compulsive behaviors (P<0.05). The mean Korean-attention-deficit/hyperactivity disorder Rating Scale-IV (K-ARS-IV) score was 11.3±7.7, with 17.1% of participants exceeding the clinical threshold. Conclusion Children with TD/TS and normal cognitive development demonstrate specific neurocognitive weaknesses and elevated behavioral/emotional problems. Early behavioral and cognitive assessments should be incorporated into the initial evaluation.

Rectal cancer, which accounts for approximately 40% of colorectal cancers, remains a major clinical concern. Recent advances in diagnostic imaging, surgical techniques, radiotherapy, and systemic treatment have steadily improved rectal cancer outcomes. Considering this, the Korean Rectal Cancer Multidisciplinary (KRCM) Committee has aimed to provide clinicians and policymakers with up-to-date, evidence-based clinical practice guidelines to support optimal decision-making, reflecting current evidence, the Korean healthcare context, and patient values and preferences. The Clinical Practice Guidelines for Rectal Cancer version 2.0 were developed through multidisciplinary collaboration with related academic societies, building upon and updating the KRCM Clinical Practice Guidelines version 1.0 (titled “Multidisciplinary guidelines for the management of rectal cancer”). These consensus guidelines of the KRCM were established based on a comprehensive literature review, evidence synthesis, with recommendation development guided by the GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology, and consideration of applicability in real-world clinical practice under the national health insurance system. Each recommendation has been presented with its strength and level of evidence.

Background: Non-thermal atmospheric pressure plasma (NTAP) generates reactive oxygen species, reactive nitrogen species, and ultraviolet radiation, which can inactivate microorganisms.Onychomycosis treatment is challenging, and its prognosis is poor owing to mixed infections and dermatophytosis. Although NTAP has shown in vitro antifungal effects against dermatophytes and yeast, its efficacy against non-dermatophyte molds (NDMs) and in clinical or nail model studies remains poorly understood. Objective: We evaluated the effects of NTAP on fungi, including NDMs, and infected nail plates. Methods: For the in vitro experiments, Trichophyton rubrum, Candida albicans, Aspergillus fumigatus, and Fusarium oxysporum strains were exposed to NTAP. After NTAP exposure (2,4 and 6 minutes), growth curve, cell viability, and biofilm biomass were assessed by absorbance wavelength of 600 nm, XTT assay, and crystal violet staining, respectively. For the ex vivo experiments, infected nail plates were analyzed using a scanning electron microscope. Results: T. rubrum and C. albicans showed greater growth inhibition with increasing NTAP exposure time, whereas A. fumigatus showed enhanced growth after 6 minutes exposure. Many fungal elements within the subungual hyperkeratosis of the ex vivo specimen were all damaged following NTAP exposure. Conclusion NTAP has antifungal effects on dermatophytes, yeast, and NDMs. We suggest that the intensity and time of NTAP application should be adjusted according to each strain and can be more effective when NTAP directly reaches the hyphae on the nail bed or subungual hyperkeratosis.