Coronavirus disease 2019 (COVID-19) is a multi-system disease that can lead to various severe complications. Acute limb ischemia (ALI) has been increasingly recognized as a COVID-19-associated complication that often predicts a poor prognosis. However, the pathophysiology and molecular mechanisms underlying COVID-19-associated ALI remain poorly understood. Hypercoagulability and thrombosis are considered important mechanisms, but we also emphasize the roles of vasospasm, hypoxia, and acidosis in the pathogenesis of the disease. The angiotensin-converting enzyme 2 (ACE2) pathway, inflammation, and platelet activation may be important molecular mechanisms underlying these pathological changes induced by COVID-19. Furthermore, we discuss the hypotheses of risk factors for COVID-19-associated ALI from genetic, age, and gender perspectives based on our analysis of molecular mechanisms. Additionally, we summarize therapeutic approaches such as use of the interleukin-6 (IL-6) blocker tocilizumab, calcium channel blockers, and angiotensin-converting enzyme inhibitors, providing insights for the future treatment of coronavirus-associated limb ischemic diseases.
Humans ; COVID-19/physiopathology* ; Ischemia/etiology* ; SARS-CoV-2 ; Extremities/blood supply* ; Risk Factors ; Interleukin-6/antagonists & inhibitors* ; Acute Disease ; Angiotensin-Converting Enzyme 2

Objective:To investigate the changes and clinical significance of vascular endothelial growth factor (VEGF) and vascular cell adhesion molecule-1 (VCAM-1) levels in patients undergoing breast cancer resection before and after radiotherapy.Methods:A total of 110 patients who were treated in our hospital from Jun. 2022 to Jun. 2023 for breast cancer and were to receive radiotherapy after surgery were prospectively selected as the observation group. Another 110 healthy volunteers were selected as the control group. The levels of VEGF and VCAM-1 in peripheral blood were compared, and the relationship among general data, tumor pathology and peripheral blood VEGF and VCAM-1 in the observation group was analyzed, and their relationship with disease and prognosis was analyzed.Results:VEGF and VCAM-1 levels in peripheral blood in the observation group were significantly higher ( F=1288.37, 309.32, P<0.05). The levels of VEGF and VCAM-1 in peripheral blood in the observation group were significantly lower than before radiotherapy ( t=23.45, 11.88, P<0.05). Before and after radiotherapy, VEGF and VCAM-1 levels in peripheral blood in the observation group were correlated with tumor stage, tumor differentiation degree and Ki-67 proliferation index ( ttumor stage=7.05, 2.14, 4.52, 4.76, ttumor differentiation degree=7.12, 6.62, 2.81, 3.15, tKi67 proliferation index=7.25, 4.60, 4.24, 2.48, P<0.05) ; Of 110 patients in the observation group, 73 were effective and 34 were ineffective. VEGF and VCAM-1 in effective group were significantly lower ( t=7.27, 9.08, P<0.05). Spearman correlation coefficient analysis showed that VEGF and VCAM-1 levels were significantly positively correlated with tumor stage and Ki67 proliferation index before and after radiotherapy ( rbefore radiotherapy=0.64, 0.54, 0.52, 0.52, rafter radiotherapy=0.32, 0.39, 0.37, 0.24, P<0.05), and negatively correlated with tumor differentiation degree ( rbefore radiotherapy=-0.41, -0.31, rafter radiotherapy=-0.68, -0.41, P<0.05). The prognostic value of combined radiotherapy was 0.801 [95% CI (0.714-0.871) ], which was higher than that of VEGF and VCAM-1 alone 0.690 [95% CI (0.5955-0.775) ] and 0.734 [95% CI (0.641-0.814) ]. Conclusion:The changes of VEGF and VCAM-1 levels in peripheral blood have a certain value in evaluating the short-term prognosis of patients undergoing breast cancer resection by radiotherapy.

Objective:To investigate the effects of the "TECK" (theoretical class, experimental course, case discussion, and knowledge reinforcement) teaching model oriented by post competency in clinical pathology internship teaching.Methods:The intern students from 2015 to 2019 in the pathology direction of clinical medicine in the School of Pathology, Qiqihar Medical College, who were enrolled in the internship from 2019 to 2023, were selected as the research objects.We enrolled 32 medical students from grades 2017, 2018, and 2019 (research group) and 24 medical students from grades 2015 and 2016 (control group) who would participate in pathology internships. The control group adopted the traditional internship mode, while the research group adopted the competency-oriented "TECK" teaching mode. After the internship, the two groups were compared for internship assessment score and surveyed for post competency. With the use of SPSS 18.0 statistical software. Continuous data were presented as (mean±standard deviation) and t-test was used for comparison between groups. Count data were expressed in the number of cases, and chi-square test was used for comparison between groups.The significance level α was 0.05. Results:The research group showed significantly higher scores of skill assessment (82.81±4.20 vs. 79.58±5.09) and pathological diagnosis assessment (80.28±4.23 vs. 76.21±4.58) than the control group (both P<0.05), with no significant difference in the score of theoretical knowledge ( P>0.05). In terms of post competency, the research group was superior to the control group in clinical skills and medical care ability (12.38±0.94 vs. 11.35±0.76), disease prevention and health promotion ability (6.28±0.92 vs. 4.48±0.93), interpersonal communication and information management ability (19.81±1.09 vs. 17.00±1.28), and teamwork and scientific research ability (11.44±1.27 vs. 9.25±0.87; all P<0.05). There were no significant differences between the two groups in core values and professional literacy and medical knowledge and lifelong learning (both P>0.05). Conclusions:In undergraduate internships, the competency-oriented "TECK"teaching mode can significantly improve students' clinical operation and pathological diagnosis ability, and effectively cultivate their abilities of clinical skills and medical care, disease prevention and health promotion, interpersonal communication and information management, teamwork and scientific research.

Objective To explore the age-related biological properties of bone-derived mesenchymal stem cells(BMSCs)from mice of different age groups and their osteogenic differentiation induced by bone morphogenetic protein 2(BMP2).Methods Eight C57BL/6J mice were divided into a young group(4 weeks old,weighing 10～15 g,n=4)and an old group(12 months old,weighing 20～25 g,n=4),with half male and half female.MSCs were extracted from the whole bones of the 2 groups of mice.After the obtained cells were identified with flow cytometry for the surface markers,β-galactosidase staining was employed to compare the senescence level of BMSCs,MTT and EdU incorporation assays were conducted to compare the proliferation and self-renewal abilities of between the 2 groups.Western blotting was employed to analyze the expression of CyclinD1 and P21 in BMSCs.Then ALP staining,Alizarin Red staining and RT-qPCR were used to evaluate the osteogenic differentiation ability of the cells.RNA sequencing was performed to compare the differential gene expression in BMP2-induced BMSCs.Lastly,the sequencing results were re-confirmed by using flow cytometry.Results Flow cytometry showed that the sorted and cultured mouse BMSCs met the criteria for MSCs.The results of β-galactosidase staining indicated that the senescence level of BMSCs in the old group was significantly higher than that in the young group(P＜0.05).MTT and EdU doping experiments revealed that the cell viability and proliferation ability of BMSCs were significantly lower in the old group than the young group(P＜0.05).Western blotting displayed that the expression level of cell cycle protein CyclinD1 was lower,whereas that of cell cycle inhibitory factor P21 was significantly higher in the BMSCs from the old group than the cells from the young group(P＜0.05).ALP/Alizarin Red staining and RT-qPCR demonstrated that the BMSCs from the young group had stronger osteogenic differentiation capacity after BMP2 treatment when compared the cells of the old group(P＜0.05).RNA sequencing results displayed that the changing profile of CD51 expression was in opposite trends in the young and old BMSCs after BMP2 treatment.Finally,flow cytometry revealed that the percentage of CD51+cells within the CD45-cells was significantly higher in the young group than the old group.Conclusion The decrease in the percentage of CD51+cells among CD45-cells in aged BMSCs is closely associated with their decreased responsiveness to BMP2-induced osteogenic differentiation.

Objective:To investigate the mechanism of miR-218-5p regulating the glycolytic process in human non-small cell lung cancer A549 cells by targeting phosphodiesterase 7A(PDE7A).Methods:A549 cells were routinely cultured,and miR-218-5p mimic,mimic-NC,PDE7A overexpression plasmid(PDE7A-oe)and PDE7A control plasmid(PDE7A-NC)were transfected into A549 cells using Lipo3000,and recorded as the miR-218-5p mimic group,the mimic-NC group,the PDE7A-oe group and the PDE7A-NC group.The transfection efficiency was verified by qPCR assay;the expressions of glycolysis key enzyme proteins were detected by WB assay;the 2-deoxyglucose and lactate contents in A549 cells of each transfection group were detected by glucose assay and lactate production assay;the target binding relationship between miR-218-5p and PDE7A was verified by dual-luciferase reporter gene assay,and the data from the TCGA database were used to analyze the expression level of PDE7A mRNA in lung cancer tissues.Results:miR-218-5p was successfully overexpressed in A549 cells(P<0.01).Overexpression of miR-218-5p significantly inhibited the expressions of PDE7A,HK2,PKM2 proteins(all P<0.01),glucose uptake and lactate production(both P<0.01)in A549 cells.Overexpression of PDE7A significantly promoted the expressions of PDE7A,HK2,and PKM2 proteins(all P<0.01),as well as glucose uptake and lactate production(both P<0.01)in A549 cells.miR-218-5p in A549 cells could directly bind to the 3′-UTR of PDE7A mRNA.Database data analysis showed that PDE7A mRNA was highly expressed in lung squamous cell carcinoma tissues(P<0.01).Conclusion:miR-218-5p targets PDE7A to regulate the expression levels of HK2 and PKM2 in A549 cells,which in turn inhibits the glycolytic process.miR-218-5p/PDE7A may be a potential target for clinical diagnosis and treatment of NSCLC.

Acral melanoma(AM)is the most common histologic subtype of melanoma in dark-skinned patients and is associated with a worse prognosis and a high mortality rate,largely due to the inconspicuous nature of early-stage lesions,which can lead to late diagnosis.Because of the overlapping clinical and histopathological features of AM with other forms of cutaneous melanomas,early detection of AM requires a multidisciplinary approach that integrates various diagnostic modalities,including clinical examination,dermoscopy,histopathology,molecular testing,radiological imaging,and blood tests.While surgery is the preferred method of treatment for AM,other therapeutic options may be employed based on the stage and underlying etiology of the disease.Immune checkpoint inhibitors,molecular targeted therapy,radiotherapy,chemotherapy,and oncolytic virotherapy represent promising advanced treatment options for AM.In this review,we provide an overview of the latest advancements in diagnostic and therapeutic methods for AM,highlighting the importance of early detection and the prompt,individualized management of this challenging disease.

Objective:To explore the psychological experience and demand of parents of children with delayed recovery after congenital heart disease surgery.Methods:This study adopted phenomenological research methods from qualitative research. Using the purposive sampling method, parents of postoperative delayed recovery children with congenital heart disease who met the inclusion criteria were selected as the research objects from October to November 2019 at Fuwai Hospital, Chinese Academy of Medical Sciences. Semi-structured interviews were conducted with the parents of the children, and the data were analyzed by Colaizzi 7-step analysis method.Results:Finally, 13 parents of children with delayed recovery after congenital heart disease surgery were included. According to the interview results, four themes were extracted, which were negative psychological experience of parents of children with delayed recovery, positive psychological experience and expectation change of parents, heavy economic burden of parents and diversified needs of parents.Conclusions:During the delayed recovery period, psychological experience of parents is complex and their needs are diverse. The nursing staff should identify and pay attention to the causes of the negative psychological experience of the parents of the children, timely channel their negative emotions and strengthen the positive psychological experience in many aspects. They can assist parents to seek social help to reduce physical and mental pressure and meet the diverse needs of parents by providing high-quality nursing services and multi-channel information support.

The goal of Medical Immunology is to enable students to pay attention to integration of immunology theory with clini-cal practice,be familiar with professional English,consciously pay attention to cutting-edge knowledge,and can learn independently and lifelong.However,existing teaching models lack explanation of clinical disease related events,and arrangement of experimental content and projects is seriously disconnected from clinical practice,scientific research on solving clinical problems is clearly insuffi-cient.We established a"B to B"cycle model for immunology teaching by starting from clinical practical problems(Bedside),return to basic research(Bench),and then solve clinical problem(Bedside),which will comprehensively cultivate senior medical profession-als with clinical competence,scientific research thinking ability,innovative spirit,and international perspective.

Scientific journals are an important platform for academic exchange and dissemination, as well as for promoting technological innovation. This article is based on the publishing practice of the Chinese Journal of Radiological Medicine and Protection in recent years, especially after being successfully selected in the Excellent Action Plan of Chinese Science and Technology Journals. It aims to gather high-quality manuscript sources and strictly control academic quality; Pay attention to academic hotspots and strengthen content construction; Based on the characteristics of publishing, create high-quality works; To fulfill our original mission, shoulder social responsibility, strengthen academic leadership, enhance brand value, and explore how to improve the quality and dissemination of academic journal content and influence, in order to better showcase and promote China's achievements in radiation medicine and protection.

Under background of new medical science,how to train high-quality medical talents with post competence is one of important contents of medical higher education.In order to train professional medical talents in different fields,make them more suitable for characteristics of their majors,and adapt to needs of future career development,"precision teaching"should be carried out in teaching,including precision of course content design,teaching mode and assessment method,so as to achieve goal of cultivating professional medical talents with precision.Therefore,guided by competency of new medical posts,our teaching team try to explore precision teaching in course construction of Medical Immunology.Here we introduce specific method by taking chapter of Antibody as an example.