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

With the rapid development of artificial intelligence(AI),how to digitize the teaching of Medical Immunology is a new challenge posed by the times and education.This study is based on the advanced teaching model of Medical Immunology,which includes lectures-PAD class-flipped classrooms-expert lecture.By introducing knowledge mapping and AI teaching assistant into the entire learning process,the students not only deepen their understanding of the knowledge system of Medical Immunology,but also ex-ercise their ability to apply immunological knowledge to solve practical clinical problems,enhance their self-learning ability,expres-sion ability,communication ability,on-site performance ability,and cultivate a spirit of unity,cooperation,and exploration.The practice of empowering Medical Immunology teaching with digital intelligence achieves the integration of theory and application,the linkage between in class and out of class teaching,the connection between commonalities and individualities,and the union of abili-ties and qualities in Medical Immunology teaching.It also provides practical basis for exploring the implementation path of digital intel-ligence empowerment in Medical Immunology teaching.

Objective To investigate the expression level of centromere protein(CENP)Ⅰin lung adenocarcinoma cells,to study the effects of CENPⅠon the proliferation,invasion,migration,apoptosis,and epithelial-mesenchymal transition(EMT)of lung adenocarci-noma cells,and to explore the possible mechanisms related to its occurrence.Methods The expression of CENPⅠmRNA and protein in four types of lung adenocarcinoma cells and normal alveolar epithelial cells were detected by quantitative real-time polymerase chain reaction(RT-qPCR)and Western blotting.The expression of CENPⅠin H1650 cells was knocked down by the siRNA technique,The transfection efficiency was detected by RT-qPCR and Western blotting.The effects of knock-down CENPⅠon proliferation,cell cycle,apoptosis,invasion and migration of H1650 cells were detected by the cell counting kit-8 assay,the transwell assay,and flow cytometry.Western blotting was used to detect the expression of E-cadherin,N-cadherin,vimentin,Ki-67,cyclin D1,Bcl-2,PI3K,AKT,mTOR,p-PI3K,p-AKT,and p-mTOR.Results After the knock-down of CENPⅠ,the proliferative ability of the H1650 cells significantly decreased,the number of apoptotic cells significantly decreased,and the cell invasion and migration abilities significantly decreased(P<0.01).E-cadherin expression was upregulated and N-cadherin,vimentin,Ki-67,cyclin D1,Bcl-2,p-PI3K,p-AKT,and p-mTOR expres-sion were down-regulated in the CENTI group compared with the control group(P<0.05).The expression of p-PI3K,p-AKT,and p-mTOR in the si-CENPⅠ+IGF-1 group was upregulated compared to that in the si-CENPⅠgroup(P<0.05).Conclusion High expression of CENPⅠin lung adenocarcinoma cells promotes the proliferation,invasion,and migration of lung adenocarcinoma H1650 cells and EMT inhibits apoptosis,which may be related to the activation of the PI3K/AKT/mTOR signaling pathway.

Theory and technology of Medical Immunology are widely used in scientific research.Our teaching and research group uses experimental teaching of Medical Immunology as a platform to carry out practice of scientific research project-based experi-mental system among"5+3"integration students.By completing a mini-project research including experimental design-experimental operation-research article writing,students cultivated scientific research thinking and exercised scientific research practice ability,and generally reported that the course is very difficult,but after completing it,it is very rewarding.

Objective To investigate the expression level of centromere protein(CENP)Ⅰin lung adenocarcinoma cells,to study the effects of CENPⅠon the proliferation,invasion,migration,apoptosis,and epithelial-mesenchymal transition(EMT)of lung adenocarci-noma cells,and to explore the possible mechanisms related to its occurrence.Methods The expression of CENPⅠmRNA and protein in four types of lung adenocarcinoma cells and normal alveolar epithelial cells were detected by quantitative real-time polymerase chain reaction(RT-qPCR)and Western blotting.The expression of CENPⅠin H1650 cells was knocked down by the siRNA technique,The transfection efficiency was detected by RT-qPCR and Western blotting.The effects of knock-down CENPⅠon proliferation,cell cycle,apoptosis,invasion and migration of H1650 cells were detected by the cell counting kit-8 assay,the transwell assay,and flow cytometry.Western blotting was used to detect the expression of E-cadherin,N-cadherin,vimentin,Ki-67,cyclin D1,Bcl-2,PI3K,AKT,mTOR,p-PI3K,p-AKT,and p-mTOR.Results After the knock-down of CENPⅠ,the proliferative ability of the H1650 cells significantly decreased,the number of apoptotic cells significantly decreased,and the cell invasion and migration abilities significantly decreased(P<0.01).E-cadherin expression was upregulated and N-cadherin,vimentin,Ki-67,cyclin D1,Bcl-2,p-PI3K,p-AKT,and p-mTOR expres-sion were down-regulated in the CENTI group compared with the control group(P<0.05).The expression of p-PI3K,p-AKT,and p-mTOR in the si-CENPⅠ+IGF-1 group was upregulated compared to that in the si-CENPⅠgroup(P<0.05).Conclusion High expression of CENPⅠin lung adenocarcinoma cells promotes the proliferation,invasion,and migration of lung adenocarcinoma H1650 cells and EMT inhibits apoptosis,which may be related to the activation of the PI3K/AKT/mTOR signaling pathway.

With the rapid development of artificial intelligence(AI),how to digitize the teaching of Medical Immunology is a new challenge posed by the times and education.This study is based on the advanced teaching model of Medical Immunology,which includes lectures-PAD class-flipped classrooms-expert lecture.By introducing knowledge mapping and AI teaching assistant into the entire learning process,the students not only deepen their understanding of the knowledge system of Medical Immunology,but also ex-ercise their ability to apply immunological knowledge to solve practical clinical problems,enhance their self-learning ability,expres-sion ability,communication ability,on-site performance ability,and cultivate a spirit of unity,cooperation,and exploration.The practice of empowering Medical Immunology teaching with digital intelligence achieves the integration of theory and application,the linkage between in class and out of class teaching,the connection between commonalities and individualities,and the union of abili-ties and qualities in Medical Immunology teaching.It also provides practical basis for exploring the implementation path of digital intel-ligence empowerment in Medical Immunology teaching.

Theory and technology of Medical Immunology are widely used in scientific research.Our teaching and research group uses experimental teaching of Medical Immunology as a platform to carry out practice of scientific research project-based experi-mental system among"5+3"integration students.By completing a mini-project research including experimental design-experimental operation-research article writing,students cultivated scientific research thinking and exercised scientific research practice ability,and generally reported that the course is very difficult,but after completing it,it is very rewarding.

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 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.

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.