Objective To investigate the effects of syncytial formation induced by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)spike protein(SARS-2-S)on the proliferation and migration of human lung adenocarcinoma A549 cells and mouse melanoma B16 cells in vitro.Methods Plasmids expressing human angiotensin-converting enzyme 2(hACE2)and SARS-2-S were constructed and respectively co-transfected with lentiviral packaging plasmids into HEK-293FT cells before the lentiviral supernatant was collected and infected with A549 cells which were screened by puromycin to obtain the A549 cells respectively that were stably transfected with hACE2(A549-A)and SARS-2-S(A549-S).The protein expression of A549-A and A549-S cells was verified by Western blotting.A549-A and A549-S cells were co-cultured before their syncytia were observed by fluorescence microscopy.Conditioned media(syncytial supernatant and non-syncytial supernatant)was collected to culture A549 cells,ovalbumin(OVA)-gene-modified B16 cells(B16-OVA),and B16-F10 cells in vitro.The CCK-8 assay and colony formation assay were used to assess the proliferation capacity of tumor cells,while the wound healing assay was employed to evaluate the migration capacity of tumor cells.Results Stable A549 cell lines expressing hACE2 and SARS-2-S were constructed.The SARS-2-S-induced syncytial formation system was established after co-culture of A549-A and A549-S cells.Both syncytial and non-syncytial supernatants significantly promoted the proliferation and migration of A549,B16-OVA,and B16-F10 cells in vitro,especially the syncytial supernatant.Conclusion SARS-2-S-induced syncytial formation promotes the proliferation and migration properties of A549 and B16 cells in vitro.

Objective:To investigate effects of implantation of pectoralis major fascia combined with serratus anterior fatty fascia flap prosthesis on breast reconstruction after early breast cancer surgery.Methods:A total of 62 patients with early breast cancer undergoing breast reconstruction in Dongguan People's Hospital of Guangdong Province from July 2017 to December 2019 were selected and randomly divided into two groups, 31 cases in each group. The control group was treated with pectoralis major fascia covering prosthesis for breast reconstruction, and the observation group was treated with pectoralis major fascia combined with serratus anterior fatty fascia flap covering prosthesis for breast reconstruction. The clinical data of the two groups were recorded, the postoperative aesthetic appearance of breast was evaluated. According to the function assessment of cancer therapy-breast cancer (FACT-B) was used to evaluate the score of quality of life before and after operation, and postoperative complications were also observed.Results:In the control group and the observation group, the intraoperative blood loss was (82.61±12.38) ml, (88.76±13.57) ml, respectively; and drainage tube extubation time was (3.51±0.62) d and (3.64±0.58) d, respectively; there was no statistically significant difference between the two groups ( t value was 1.864, 0.853, respectively, all P > 0.05). The operation time of the observation group was longer than that of the control group [(2.59±0.29) h vs. (1.72±0.32) h, t = 11.217, P < 0.001]. The amount of drainage of the control group was higher than that of the observation group [(215.45±47.69) ml vs. (151.36±31.67) ml, t = 6.233, P < 0.001]; the length of hospital stay of the control group was longer than that of the observation group [(14.51±2.32) d vs. (10.79±1.86) d, t = 6.965, P < 0.001]. The excellent and good rate of postoperative breast appearance of the observation group was higher than that of the control group [96.77% (30/31) vs. 74.19% (23/31), χ 2adjusted=4.679, P = 0.031]. There were no statistical differences in all items including health, emotion, function, society/family and other conditions scores of FACT-B and total scores in both groups before the operation (all P > 0.05); all items scores and total scores of both groups after the operation were higher than those before the operation (all P < 0.001), and the sores after the operation of the observation group were higher than those of the control group (all P < 0.001). The total incidence of postoperative complications was 6.45% (2/31) of the observation group, 22.58% (7/31) of the control group, and the difference was not statistically significant (χ 2adjusted=2.080, P = 0.149). Conclusion:Breast reconstruction with implantation of pectoralis major fascia combined with serratus anterior fatty fascia flap prosthesis after early breast cancer surgery can shorten the postoperative hospital stay, improve the aesthetic appearance of breast, improve the long-term quality of life, and has a high safety.

Objective:To analyze the risk factors for lymph node metastasis in breast cancer patients with axillary lymph node metastasis after neoadjuvant chemotherapy.Methods:The data of 94 female patients with invasive breast cancer in Dongguan People′s Hospital of Guangdong Province from January 2017 to December 2019 were retrospectively analyzed.All patients planned to receive 4-8 cycles of neoadjuvant chemotherapy.After chemotherapy, modified radical mastectomy was performed.Estrogen receptor(ER), progesterone receptor(PR) and human epidermal growth factor receptor 2(HER-2) appeared for the first time in Chinese and English abstracts and texts positive patients received endocrine or targeted therapy.The rest patients received 2-4 cycles of adjuvant chemotherapy or radiotherapy according to the situation.Lymph node metastasis after neoadjuvant chemotherapy was analyzed.The relationship between lymph node metastasis after neoadjuvant chemotherapy and clinicopathological features was analyzed.Risk factors for lymph node metastasis after neoadjuvant chemotherapy were analyzed by Logistic regression.Results:After neoadjuvant chemotherapy, the positive rate of axillary lymph node was 74.47%(70/94). The number of positive axillary lymph nodes, ER status, HER-2 status and cell proliferation-associated human nuclear antigen(Ki67), the completion of chemotherapy cycle, the pathological remission of axillary lymph nodes after chemotherapy and the T stage of tumor after neoadjuvant chemotherapy were associated with lymph node metastasis in patients with positive axillary lymph nodes after neoadjuvant chemotherapy(χ 2=30.053, 10.233, 6.303, 7.666, 18.162, 10.148, 12.418; all P<0.05). More than 3 positive axillary lymph nodes( OR=2.788, 95% CI 1.253-5.318), ER positive( OR=3.298, 95% CI 1.744-7.837), Ki67 positive( OR=2.469, 95% CI 1.184-4.301)and pathological pPR( OR=4.197, 95% CI 2.168-13.788) were independent risk factors for lymph node metastasis after neoadjuvant chemotherapy(all P<0.05). Conclusion:Axillary lymph node-positive breast cancer patients have a high positive rate of axillary lymph nodes after neoadjuvant chemotherapy.More than 3 positive axillary lymph nodes before operation, ER positive, Ki67 positive, and axillary lymph node pPR after neoadjuvant chemotherapy are independent risk factors for lymph node metastasis after neoadjuvant chemotherapy.

Objective To observe the effect of local injections of Pseudomonas Aeruginosa Preparation joint compres-sion bandage in lymph leakage after breast carcinoma operation. Methods A total of 60 patients of lymph leakage after breast carcinoma operation were randomly divided into the observation group and the control group , the pations of ob-servation group was treated with pseudomonas aeruginosa preparation joint compression bandage treatment ,while the pations of control group was treated with the puncture pumping local joint compression bandage treatment , the clinical efficacy of two groups were compared. Results The treatment group cure rate was 76.7%, effective rate was 96.7%, control group 20.0%, 66.7% respectively. The difference was statistically significant (P<0.05).After treatment, KPS score of the observation group was significantly better than the control group, drainage time, hospitalization time was shortened (P<0.05), the expected survival was not significantly different (P>0.05).There were no serious adverse reac-tionsin two groups. Conclusion Pseudomonas Aeruginosa Preparation joint compression bandage has definite clinical effect in lymph leakage after breast carcinoma operation,less adverse reaction.