Objective:To explore the characteristics of bone marrow morphology and the phenotypic features involved in the flow cytometry (FCM)-based erythroid scoring system in low-risk myelodysplastic syndromes (MDS).Methods:A retrospective case series study was conducted. The clinical data of 13 low-risk MDS patients and 20 non-MDS patients (including 8 cases of iron deficiency anemia, 5 cases of thrombocytopenia, 3 cases of infectious diseases, and 4 cases of leukopenia) collected from outpatient or inpatient samples of multiple hospitals from March 2019 to December 2023 were retrospectively analyzed. The bone marrow morphology examination was performed using Wright-Giemsa staining; the immunophenotypic profiles of erythroblasts were evaluated by FCM; G-banding technique was used to analyze the chromosome karyotypes; next-generation sequencing technology was used for molecular biology detection.Results:Among the 13 low-risk MDS patients, there were 6 males and 7 females, with a median age of 61 years (IQR 15 years). Bone marrow morphological examination showed that the dysplastic hematopoietic morphology of erythroblasts was observed in the bone marrow of 13 low-risk MDS patients, with abnormal nuclear morphology such as odd nuclei, mother-daughter nuclei, petal nuclei, inter-nuclear bridges, multinucleated giants (including abnormal pentanucleated forms), and small megakaryocytes; pathological hematopoiesis in bone marrow accounted for 10%-15% of the erythroblasts system; FCM detection showed that the myeloid primitive cells occupied 0-1.2% of nuclear cells in the bone marrow of low-risk MDS group, expressing CD117, HLA-DR and CD33, partially expressing CD34 and CD38, and not expressing CD19, CD56 and CD7; the developmental pattern of granulocyte CD13/CD16/CD11b was basically normal; partial expression of CD36 and CD71 in erythroblasts was missing. The expression of CD36 and CD71 in erythroblasts of non-MDS group was normal. The expression rates of CD36 in low-risk MDS group and non-MDS group were (51.57±0.13)% and (93.50±0.03)%, respectively ( t = -6.32, P < 0.001), while the expression rates of CD71 were (22.24±0.05)% and (87.94±0.04)%, respectively ( t = -9.47, P < 0.001), with statistically significant differences. The coefficient of variation (CV) of mean fluorescence intensity of CD36 in low-risk MDS group and non-MDS group were 155±8 and 57±10, respectively ( t = 29.18, P < 0.001), and the CV of mean fluorescence intensity of CD71 was 204±33 and 56±6, respectively ( t = 19.43, P <0.001), with statistically significant differences. Among 13 low-risk MDS patients, 4 had abnormal bone marrow chromosome karyotypes, including -7, 8, del(20q), -Y, +15, etc; 5 cases had clonal gene mutations detected by next-generation sequencing, such as ASXL1, SRSF2, TET2, DNMT3A, etc; no 5q-, SF3B1 or TP53 gene mutation was detected. Patients were followed up until December 2023, among the 13 low-risk MDS patients, 7 cases achieved good clinical efficacy, 2 cases transformed into high-risk MDS with excess blasts after 1 year, 3 cases transformed into acute myeloid leukemia M 2 2 years later, and the treatment efficacy of 1 case was unknown. Conclusions:Low-risk MDS patients have pathological hematopoiesis of erythroblasts morphologically. FCM detection shows abnormal developmental patterns of erythroblasts combined with elevated CV of average fluorescence intensity, and often accompanied by genetic abnormalities.

Objective:To retrospectively construct competency-based portfolios for medical students to analyze the factors influencing competency self-assessment, and to explore an approach to efficient portfolio construction.Methods:The participants were randomly selected among medical graduates of 2015 in Shantou University Medical College. Through records collection and an online questionnaire survey, portfolios were built for the participants based on their development data during eight years from college entrance, college education, to post-graduation medical education. The correlation between variables was determined using Kendall's tau-b correlation coefficients. The inter-group differences were analyzed using the Mann-Whitney U test. Results:A total of 126 usable questionnaires for effective developmental portfolios were collected. There were a total of 208 indicators collected, including 79 questionnaire indicators (including 36 for competency self-assessment). The reliability coefficient (Cronbach's α) of the questionnaire was 0.984. The factors related to competency self-assessment were identified. Conclusion:This study provides a basis for the implementation of portfolio assessment, which can promote students' self-assessment and competency development. Optimizing the indicator system, building an online platform, increasing participants' participation motivation, and emphasizing self-reflection and feedback will help improve the efficiency of developmental portfolio construction and its performance.